TE X AS I NS TRUM E NTS - P RO DUCTION D ATA ® Stellaris LM3S9U90 Microcontroller D ATA SHE E T D S -LM3S 9U 90 - 1 5 8 5 2 . 2 7 4 3 S P M S 252C C o p yri g h t © 2 0 07-2014 Te xa s In stru me n ts In co rporated Copyright Copyright © 2007-2014 Texas Instruments Incorporated All rights reserved. Stellaris and StellarisWare® are registered trademarks of Texas Instruments Incorporated. ARM and Thumb are registered trademarks and Cortex is a trademark of ARM Limited. Other names and brands may be claimed as the property of others. PRODUCTION DATA information is current as of publication date. Products conform to specifications per the terms of Texas Instruments standard warranty. Production processing does not necessarily include testing of all parameters. Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet. Texas Instruments Incorporated 108 Wild Basin, Suite 350 Austin, TX 78746 http://www.ti.com/stellaris http://www-k.ext.ti.com/sc/technical-support/product-information-centers.htm 2 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Table of Contents Revision History ............................................................................................................................. 40 About This Document .................................................................................................................... 43 Audience .............................................................................................................................................. About This Manual ................................................................................................................................ Related Documents ............................................................................................................................... Documentation Conventions .................................................................................................................. 43 43 43 44 1 Architectural Overview .......................................................................................... 46 1.1 1.2 1.3 1.3.1 1.3.2 1.3.3 1.3.4 1.3.5 1.3.6 1.3.7 1.3.8 1.4 Overview ...................................................................................................................... Target Applications ........................................................................................................ Features ....................................................................................................................... ARM Cortex-M3 Processor Core .................................................................................... On-Chip Memory ........................................................................................................... External Peripheral Interface ......................................................................................... Serial Communications Peripherals ................................................................................ System Integration ........................................................................................................ Analog .......................................................................................................................... JTAG and ARM Serial Wire Debug ................................................................................ Packaging and Temperature .......................................................................................... Hardware Details .......................................................................................................... 46 48 48 48 50 51 53 59 64 66 67 67 2 The Cortex-M3 Processor ...................................................................................... 68 2.1 2.2 2.2.1 2.2.2 2.2.3 2.2.4 2.3 2.3.1 2.3.2 2.3.3 2.3.4 2.3.5 2.3.6 2.4 2.4.1 2.4.2 2.4.3 2.4.4 2.4.5 2.4.6 2.4.7 2.5 2.5.1 2.5.2 2.5.3 Block Diagram .............................................................................................................. 69 Overview ...................................................................................................................... 70 System-Level Interface .................................................................................................. 70 Integrated Configurable Debug ...................................................................................... 70 Trace Port Interface Unit (TPIU) ..................................................................................... 71 Cortex-M3 System Component Details ........................................................................... 71 Programming Model ...................................................................................................... 72 Processor Mode and Privilege Levels for Software Execution ........................................... 72 Stacks .......................................................................................................................... 72 Register Map ................................................................................................................ 73 Register Descriptions .................................................................................................... 74 Exceptions and Interrupts .............................................................................................. 87 Data Types ................................................................................................................... 87 Memory Model .............................................................................................................. 87 Memory Regions, Types and Attributes ........................................................................... 89 Memory System Ordering of Memory Accesses .............................................................. 90 Behavior of Memory Accesses ....................................................................................... 90 Software Ordering of Memory Accesses ......................................................................... 91 Bit-Banding ................................................................................................................... 92 Data Storage ................................................................................................................ 94 Synchronization Primitives ............................................................................................. 95 Exception Model ........................................................................................................... 96 Exception States ........................................................................................................... 97 Exception Types ............................................................................................................ 97 Exception Handlers ..................................................................................................... 100 July 03, 2014 3 Texas Instruments-Production Data Table of Contents 2.5.4 2.5.5 2.5.6 2.5.7 2.6 2.6.1 2.6.2 2.6.3 2.6.4 2.7 2.7.1 2.7.2 2.8 Vector Table ................................................................................................................ Exception Priorities ...................................................................................................... Interrupt Priority Grouping ............................................................................................ Exception Entry and Return ......................................................................................... Fault Handling ............................................................................................................. Fault Types ................................................................................................................. Fault Escalation and Hard Faults .................................................................................. Fault Status Registers and Fault Address Registers ...................................................... Lockup ....................................................................................................................... Power Management .................................................................................................... Entering Sleep Modes ................................................................................................. Wake Up from Sleep Mode .......................................................................................... Instruction Set Summary .............................................................................................. 100 101 102 102 104 104 105 106 106 106 106 107 108 3 Cortex-M3 Peripherals ......................................................................................... 111 3.1 3.1.1 3.1.2 3.1.3 3.1.4 3.2 3.3 3.4 3.5 3.6 Functional Description ................................................................................................. 111 System Timer (SysTick) ............................................................................................... 111 Nested Vectored Interrupt Controller (NVIC) .................................................................. 112 System Control Block (SCB) ........................................................................................ 114 Memory Protection Unit (MPU) ..................................................................................... 114 Register Map .............................................................................................................. 119 System Timer (SysTick) Register Descriptions .............................................................. 121 NVIC Register Descriptions .......................................................................................... 125 System Control Block (SCB) Register Descriptions ........................................................ 138 Memory Protection Unit (MPU) Register Descriptions .................................................... 167 4 JTAG Interface ...................................................................................................... 177 4.1 4.2 4.3 4.3.1 4.3.2 4.3.3 4.3.4 4.4 4.5 4.5.1 4.5.2 Block Diagram ............................................................................................................ Signal Description ....................................................................................................... Functional Description ................................................................................................. JTAG Interface Pins ..................................................................................................... JTAG TAP Controller ................................................................................................... Shift Registers ............................................................................................................ Operational Considerations .......................................................................................... Initialization and Configuration ..................................................................................... Register Descriptions .................................................................................................. Instruction Register (IR) ............................................................................................... Data Registers ............................................................................................................ 178 178 179 179 181 181 182 184 185 185 187 5 System Control ..................................................................................................... 189 5.1 5.2 5.2.1 5.2.2 5.2.3 5.2.4 5.2.5 5.2.6 5.3 5.4 5.5 Signal Description ....................................................................................................... Functional Description ................................................................................................. Device Identification .................................................................................................... Reset Control .............................................................................................................. Non-Maskable Interrupt ............................................................................................... Power Control ............................................................................................................. Clock Control .............................................................................................................. System Control ........................................................................................................... Initialization and Configuration ..................................................................................... Register Map .............................................................................................................. Register Descriptions .................................................................................................. 4 189 189 190 190 195 195 196 203 205 205 207 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller 6 Hibernation Module .............................................................................................. 293 6.1 6.2 6.3 6.3.1 6.3.2 6.3.3 6.3.4 6.3.5 6.3.6 6.3.7 6.3.8 6.3.9 6.3.10 6.3.11 6.4 6.4.1 6.4.2 6.4.3 6.4.4 6.4.5 6.5 6.6 Block Diagram ............................................................................................................ Signal Description ....................................................................................................... Functional Description ................................................................................................. Register Access Timing ............................................................................................... Hibernation Clock Source ............................................................................................ System Implementation ............................................................................................... Battery Management ................................................................................................... Real-Time Clock .......................................................................................................... Battery-Backed Memory .............................................................................................. Power Control Using HIB ............................................................................................. Power Control Using VDD3ON Mode ........................................................................... Initiating Hibernate ...................................................................................................... Waking from Hibernate ................................................................................................ Interrupts and Status ................................................................................................... Initialization and Configuration ..................................................................................... Initialization ................................................................................................................. RTC Match Functionality (No Hibernation) .................................................................... RTC Match/Wake-Up from Hibernation ......................................................................... External Wake-Up from Hibernation .............................................................................. RTC or External Wake-Up from Hibernation .................................................................. Register Map .............................................................................................................. Register Descriptions .................................................................................................. 294 294 295 295 296 297 298 298 299 299 299 299 299 300 300 300 301 301 302 302 302 303 7 Internal Memory ................................................................................................... 320 7.1 7.2 7.2.1 7.2.2 7.2.3 7.3 7.4 7.5 Block Diagram ............................................................................................................ 320 Functional Description ................................................................................................. 320 SRAM ........................................................................................................................ 321 ROM .......................................................................................................................... 321 Flash Memory ............................................................................................................. 323 Register Map .............................................................................................................. 328 Flash Memory Register Descriptions (Flash Control Offset) ............................................ 330 Memory Register Descriptions (System Control Offset) .................................................. 342 8 Micro Direct Memory Access (μDMA) ................................................................ 366 8.1 8.2 8.2.1 8.2.2 8.2.3 8.2.4 8.2.5 8.2.6 8.2.7 8.2.8 8.2.9 8.2.10 8.3 8.3.1 8.3.2 Block Diagram ............................................................................................................ 367 Functional Description ................................................................................................. 367 Channel Assignments .................................................................................................. 368 Priority ........................................................................................................................ 369 Arbitration Size ............................................................................................................ 369 Request Types ............................................................................................................ 370 Channel Configuration ................................................................................................. 371 Transfer Modes ........................................................................................................... 372 Transfer Size and Increment ........................................................................................ 381 Peripheral Interface ..................................................................................................... 381 Software Request ........................................................................................................ 381 Interrupts and Errors .................................................................................................... 382 Initialization and Configuration ..................................................................................... 382 Module Initialization ..................................................................................................... 382 Configuring a Memory-to-Memory Transfer ................................................................... 383 July 03, 2014 5 Texas Instruments-Production Data Table of Contents 8.3.3 8.3.4 8.3.5 8.4 8.5 8.6 Configuring a Peripheral for Simple Transmit ................................................................ Configuring a Peripheral for Ping-Pong Receive ............................................................ Configuring Channel Assignments ................................................................................ Register Map .............................................................................................................. μDMA Channel Control Structure ................................................................................. μDMA Register Descriptions ........................................................................................ 384 386 388 388 390 397 9 General-Purpose Input/Outputs (GPIOs) ........................................................... 427 9.1 9.2 9.2.1 9.2.2 9.2.3 9.2.4 9.2.5 9.2.6 9.3 9.4 9.5 Signal Description ....................................................................................................... 427 Functional Description ................................................................................................. 431 Data Control ............................................................................................................... 433 Interrupt Control .......................................................................................................... 434 Mode Control .............................................................................................................. 435 Commit Control ........................................................................................................... 435 Pad Control ................................................................................................................. 436 Identification ............................................................................................................... 436 Initialization and Configuration ..................................................................................... 436 Register Map .............................................................................................................. 437 Register Descriptions .................................................................................................. 439 10 External Peripheral Interface (EPI) ..................................................................... 482 10.1 10.2 10.3 10.3.1 10.3.2 10.4 10.4.1 10.4.2 10.4.3 10.5 10.6 EPI Block Diagram ...................................................................................................... Signal Description ....................................................................................................... Functional Description ................................................................................................. Non-Blocking Reads .................................................................................................... DMA Operation ........................................................................................................... Initialization and Configuration ..................................................................................... SDRAM Mode ............................................................................................................. Host Bus Mode ........................................................................................................... General-Purpose Mode ............................................................................................... Register Map .............................................................................................................. Register Descriptions .................................................................................................. 483 484 486 487 488 488 489 493 504 512 513 11 General-Purpose Timers ...................................................................................... 557 11.1 11.2 11.3 11.3.1 11.3.2 11.3.3 11.3.4 11.4 11.4.1 11.4.2 11.4.3 11.4.4 11.4.5 11.5 11.6 Block Diagram ............................................................................................................ Signal Description ....................................................................................................... Functional Description ................................................................................................. GPTM Reset Conditions .............................................................................................. Timer Modes ............................................................................................................... DMA Operation ........................................................................................................... Accessing Concatenated Register Values ..................................................................... Initialization and Configuration ..................................................................................... One-Shot/Periodic Timer Mode .................................................................................... Real-Time Clock (RTC) Mode ...................................................................................... Input Edge-Count Mode ............................................................................................... Input Edge Timing Mode .............................................................................................. PWM Mode ................................................................................................................. Register Map .............................................................................................................. Register Descriptions .................................................................................................. 6 557 558 561 561 561 568 568 569 569 570 570 571 571 572 573 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller 12 Watchdog Timers ................................................................................................. 604 12.1 12.2 12.2.1 12.3 12.4 12.5 Block Diagram ............................................................................................................ Functional Description ................................................................................................. Register Access Timing ............................................................................................... Initialization and Configuration ..................................................................................... Register Map .............................................................................................................. Register Descriptions .................................................................................................. 605 605 606 606 606 607 13 Analog-to-Digital Converter (ADC) ..................................................................... 629 13.1 13.2 13.3 13.3.1 13.3.2 13.3.3 13.3.4 13.3.5 13.3.6 13.3.7 13.4 13.4.1 13.4.2 13.5 13.6 Block Diagram ............................................................................................................ 630 Signal Description ....................................................................................................... 631 Functional Description ................................................................................................. 633 Sample Sequencers .................................................................................................... 633 Module Control ............................................................................................................ 634 Hardware Sample Averaging Circuit ............................................................................. 636 Analog-to-Digital Converter .......................................................................................... 637 Differential Sampling ................................................................................................... 641 Internal Temperature Sensor ........................................................................................ 643 Digital Comparator Unit ............................................................................................... 644 Initialization and Configuration ..................................................................................... 648 Module Initialization ..................................................................................................... 648 Sample Sequencer Configuration ................................................................................. 649 Register Map .............................................................................................................. 649 Register Descriptions .................................................................................................. 651 14 Universal Asynchronous Receivers/Transmitters (UARTs) ............................. 709 14.1 Block Diagram ............................................................................................................ 14.2 Signal Description ....................................................................................................... 14.3 Functional Description ................................................................................................. 14.3.1 Transmit/Receive Logic ............................................................................................... 14.3.2 Baud-Rate Generation ................................................................................................. 14.3.3 Data Transmission ...................................................................................................... 14.3.4 Serial IR (SIR) ............................................................................................................. 14.3.5 ISO 7816 Support ....................................................................................................... 14.3.6 Modem Handshake Support ......................................................................................... 14.3.7 LIN Support ................................................................................................................ 14.3.8 FIFO Operation ........................................................................................................... 14.3.9 Interrupts .................................................................................................................... 14.3.10 Loopback Operation .................................................................................................... 14.3.11 DMA Operation ........................................................................................................... 14.4 Initialization and Configuration ..................................................................................... 14.5 Register Map .............................................................................................................. 14.6 Register Descriptions .................................................................................................. 710 710 712 712 713 714 714 715 715 717 718 719 720 720 720 721 723 15 Synchronous Serial Interface (SSI) .................................................................... 773 15.1 15.2 15.3 15.3.1 15.3.2 15.3.3 Block Diagram ............................................................................................................ Signal Description ....................................................................................................... Functional Description ................................................................................................. Bit Rate Generation ..................................................................................................... FIFO Operation ........................................................................................................... Interrupts .................................................................................................................... July 03, 2014 774 774 775 776 776 776 7 Texas Instruments-Production Data Table of Contents 15.3.4 15.3.5 15.4 15.5 15.6 Frame Formats ........................................................................................................... DMA Operation ........................................................................................................... Initialization and Configuration ..................................................................................... Register Map .............................................................................................................. Register Descriptions .................................................................................................. 777 784 785 786 787 16 Inter-Integrated Circuit (I2C) Interface ................................................................ 815 16.1 16.2 16.3 16.3.1 16.3.2 16.3.3 16.3.4 16.3.5 16.4 16.5 16.6 16.7 Block Diagram ............................................................................................................ Signal Description ....................................................................................................... Functional Description ................................................................................................. I2C Bus Functional Overview ........................................................................................ Available Speed Modes ............................................................................................... Interrupts .................................................................................................................... Loopback Operation .................................................................................................... Command Sequence Flow Charts ................................................................................ Initialization and Configuration ..................................................................................... Register Map .............................................................................................................. Register Descriptions (I2C Master) ............................................................................... Register Descriptions (I2C Slave) ................................................................................. 17 Inter-Integrated Circuit Sound (I2S) Interface .................................................... 853 17.1 17.2 17.3 17.3.1 17.3.2 17.4 17.5 17.6 Block Diagram ............................................................................................................ Signal Description ....................................................................................................... Functional Description ................................................................................................. Transmit ..................................................................................................................... Receive ...................................................................................................................... Initialization and Configuration ..................................................................................... Register Map .............................................................................................................. Register Descriptions .................................................................................................. 18 Controller Area Network (CAN) Module ............................................................. 890 816 816 817 817 819 820 821 822 829 830 831 844 854 854 855 857 861 863 864 865 18.1 Block Diagram ............................................................................................................ 891 18.2 Signal Description ....................................................................................................... 891 18.3 Functional Description ................................................................................................. 892 18.3.1 Initialization ................................................................................................................. 893 18.3.2 Operation ................................................................................................................... 894 18.3.3 Transmitting Message Objects ..................................................................................... 895 18.3.4 Configuring a Transmit Message Object ........................................................................ 895 18.3.5 Updating a Transmit Message Object ........................................................................... 896 18.3.6 Accepting Received Message Objects .......................................................................... 897 18.3.7 Receiving a Data Frame .............................................................................................. 897 18.3.8 Receiving a Remote Frame .......................................................................................... 897 18.3.9 Receive/Transmit Priority ............................................................................................. 898 18.3.10 Configuring a Receive Message Object ........................................................................ 898 18.3.11 Handling of Received Message Objects ........................................................................ 899 18.3.12 Handling of Interrupts .................................................................................................. 901 18.3.13 Test Mode ................................................................................................................... 902 18.3.14 Bit Timing Configuration Error Considerations ............................................................... 904 18.3.15 Bit Time and Bit Rate ................................................................................................... 904 18.3.16 Calculating the Bit Timing Parameters .......................................................................... 906 8 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller 18.4 18.5 Register Map .............................................................................................................. 909 CAN Register Descriptions .......................................................................................... 910 19 Ethernet Controller .............................................................................................. 941 19.1 19.2 19.3 19.3.1 19.3.2 19.3.3 19.3.4 19.3.5 19.4 19.4.1 19.4.2 19.5 19.6 19.7 Block Diagram ............................................................................................................ 942 Signal Description ....................................................................................................... 943 Functional Description ................................................................................................. 944 MAC Operation ........................................................................................................... 944 Internal MII Operation .................................................................................................. 947 PHY Operation ............................................................................................................ 947 Interrupts .................................................................................................................... 950 DMA Operation ........................................................................................................... 950 Initialization and Configuration ..................................................................................... 951 Hardware Configuration ............................................................................................... 951 Software Configuration ................................................................................................ 952 Register Map .............................................................................................................. 952 Ethernet MAC Register Descriptions ............................................................................. 954 MII Management Register Descriptions ......................................................................... 979 20 Universal Serial Bus (USB) Controller ............................................................. 1000 20.1 20.2 20.3 20.3.1 20.3.2 20.3.3 20.3.4 20.4 20.4.1 20.4.2 20.5 20.6 Block Diagram ........................................................................................................... 1001 Signal Description ..................................................................................................... 1001 Functional Description ............................................................................................... 1003 Operation as a Device ............................................................................................... 1003 Operation as a Host ................................................................................................... 1008 OTG Mode ................................................................................................................ 1012 DMA Operation ......................................................................................................... 1014 Initialization and Configuration .................................................................................... 1015 Pin Configuration ....................................................................................................... 1015 Endpoint Configuration .............................................................................................. 1016 Register Map ............................................................................................................ 1016 Register Descriptions ................................................................................................. 1027 21 Analog Comparators .......................................................................................... 1139 21.1 21.2 21.3 21.3.1 21.4 21.5 21.6 Block Diagram ........................................................................................................... Signal Description ..................................................................................................... Functional Description ............................................................................................... Internal Reference Programming ................................................................................ Initialization and Configuration .................................................................................... Register Map ............................................................................................................ Register Descriptions ................................................................................................. 22 Pin Diagram ........................................................................................................ 1153 1140 1140 1141 1142 1143 1144 1145 23 Signal Tables ...................................................................................................... 1155 23.1 23.1.1 23.1.2 23.1.3 23.1.4 23.1.5 23.2 100-Pin LQFP Package Pin Tables ............................................................................. Signals by Pin Number .............................................................................................. Signals by Signal Name ............................................................................................. Signals by Function, Except for GPIO ......................................................................... GPIO Pins and Alternate Functions ............................................................................ Possible Pin Assignments for Alternate Functions ....................................................... 108-Ball BGA Package Pin Tables .............................................................................. July 03, 2014 1156 1156 1165 1174 1181 1184 1187 9 Texas Instruments-Production Data Table of Contents 23.2.1 23.2.2 23.2.3 23.2.4 23.2.5 23.3 Signals by Pin Number .............................................................................................. Signals by Signal Name ............................................................................................. Signals by Function, Except for GPIO ......................................................................... GPIO Pins and Alternate Functions ............................................................................ Possible Pin Assignments for Alternate Functions ....................................................... Connections for Unused Signals ................................................................................. 1187 1197 1206 1213 1216 1218 24 Operating Characteristics ................................................................................. 1221 25 Electrical Characteristics .................................................................................. 1222 25.1 Maximum Ratings ...................................................................................................... 1222 25.2 Recommended Operating Conditions ......................................................................... 1222 25.3 Load Conditions ........................................................................................................ 1223 25.4 JTAG and Boundary Scan .......................................................................................... 1223 25.5 Power and Brown-Out ............................................................................................... 1225 25.6 Reset ........................................................................................................................ 1226 25.7 On-Chip Low Drop-Out (LDO) Regulator ..................................................................... 1227 25.8 Clocks ...................................................................................................................... 1227 25.8.1 PLL Specifications ..................................................................................................... 1227 25.8.2 PIOSC Specifications ................................................................................................ 1228 25.8.3 Internal 30-kHz Oscillator Specifications ..................................................................... 1228 25.8.4 Hibernation Clock Source Specifications ..................................................................... 1229 25.8.5 Main Oscillator Specifications ..................................................................................... 1229 25.8.6 System Clock Specification with ADC Operation .......................................................... 1230 25.8.7 System Clock Specification with USB Operation .......................................................... 1230 25.9 Sleep Modes ............................................................................................................. 1230 25.10 Hibernation Module ................................................................................................... 1231 25.11 Flash Memory ........................................................................................................... 1232 25.12 Input/Output Characteristics ....................................................................................... 1232 25.13 External Peripheral Interface (EPI) .............................................................................. 1233 25.14 Analog-to-Digital Converter (ADC) .............................................................................. 1239 25.15 Synchronous Serial Interface (SSI) ............................................................................. 1240 25.16 Inter-Integrated Circuit (I2C) Interface ......................................................................... 1242 25.17 Inter-Integrated Circuit Sound (I2S) Interface ............................................................... 1243 25.18 Ethernet Controller .................................................................................................... 1244 25.19 Universal Serial Bus (USB) Controller ......................................................................... 1247 25.20 Analog Comparator ................................................................................................... 1247 25.21 Current Consumption ................................................................................................. 1248 25.21.1 Nominal Power Consumption ..................................................................................... 1248 25.21.2 Maximum Current Consumption ................................................................................. 1249 A Register Quick Reference ................................................................................. 1251 B Ordering and Contact Information ................................................................... 1302 B.1 B.2 B.3 B.4 Ordering Information .................................................................................................. Part Markings ............................................................................................................ Kits ........................................................................................................................... Support Information ................................................................................................... 1302 1302 1302 1303 C Package Information .......................................................................................... 1304 C.1 C.1.1 100-Pin LQFP Package ............................................................................................. 1304 Package Dimensions ................................................................................................. 1304 10 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller C.1.2 C.1.3 C.2 C.2.1 C.2.2 C.2.3 Tray Dimensions ....................................................................................................... Tape and Reel Dimensions ........................................................................................ 108-Ball BGA Package .............................................................................................. Package Dimensions ................................................................................................. Tray Dimensions ....................................................................................................... Tape and Reel Dimensions ........................................................................................ July 03, 2014 1306 1306 1308 1308 1310 1311 11 Texas Instruments-Production Data Table of Contents List of Figures Figure 1-1. Figure 2-1. Figure 2-2. Figure 2-3. Figure 2-4. Figure 2-5. Figure 2-6. Figure 2-7. Figure 3-1. Figure 4-1. Figure 4-2. Figure 4-3. Figure 4-4. Figure 4-5. Figure 5-1. Figure 5-2. Figure 5-3. Figure 5-4. Figure 5-5. Figure 6-1. Figure 6-2. Figure 6-3. Stellaris LM3S9U90 Microcontroller High-Level Block Diagram ............................... 47 CPU Block Diagram ............................................................................................. 70 TPIU Block Diagram ............................................................................................ 71 Cortex-M3 Register Set ........................................................................................ 73 Bit-Band Mapping ................................................................................................ 94 Data Storage ....................................................................................................... 95 Vector Table ...................................................................................................... 101 Exception Stack Frame ...................................................................................... 103 SRD Use Example ............................................................................................. 117 JTAG Module Block Diagram .............................................................................. 178 Test Access Port State Machine ......................................................................... 181 IDCODE Register Format ................................................................................... 187 BYPASS Register Format ................................................................................... 188 Boundary Scan Register Format ......................................................................... 188 Basic RST Configuration .................................................................................... 192 External Circuitry to Extend Power-On Reset ....................................................... 192 Reset Circuit Controlled by Switch ...................................................................... 193 Power Architecture ............................................................................................ 196 Main Clock Tree ................................................................................................ 199 Hibernation Module Block Diagram ..................................................................... 294 Using a Crystal as the Hibernation Clock Source ................................................. 297 Using a Dedicated Oscillator as the Hibernation Clock Source with VDD3ON Mode ................................................................................................................ 297 Figure 7-1. Internal Memory Block Diagram .......................................................................... 320 Figure 8-1. μDMA Block Diagram ......................................................................................... 367 Figure 8-2. Example of Ping-Pong μDMA Transaction ........................................................... 374 Figure 8-3. Memory Scatter-Gather, Setup and Configuration ................................................ 376 Figure 8-4. Memory Scatter-Gather, μDMA Copy Sequence .................................................. 377 Figure 8-5. Peripheral Scatter-Gather, Setup and Configuration ............................................. 379 Figure 8-6. Peripheral Scatter-Gather, μDMA Copy Sequence ............................................... 380 Figure 9-1. Digital I/O Pads ................................................................................................. 432 Figure 9-2. Analog/Digital I/O Pads ...................................................................................... 433 Figure 9-3. GPIODATA Write Example ................................................................................. 434 Figure 9-4. GPIODATA Read Example ................................................................................. 434 Figure 10-1. EPI Block Diagram ............................................................................................. 484 Figure 10-2. SDRAM Non-Blocking Read Cycle ...................................................................... 492 Figure 10-3. SDRAM Normal Read Cycle ............................................................................... 492 Figure 10-4. SDRAM Write Cycle ........................................................................................... 493 Figure 10-5. Example Schematic for Muxed Host-Bus 16 Mode ............................................... 499 Figure 10-6. Host-Bus Read Cycle, MODE = 0x1, WRHIGH = 0, RDHIGH = 0 .......................... 501 Figure 10-7. Host-Bus Write Cycle, MODE = 0x1, WRHIGH = 0, RDHIGH = 0 .......................... 502 Figure 10-8. Host-Bus Write Cycle with Multiplexed Address and Data, MODE = 0x0, WRHIGH = 0, RDHIGH = 0 ............................................................................................... 502 Figure 10-9. Host-Bus Write Cycle with Multiplexed Address and Data and ALE with Dual CSn .................................................................................................................. 503 Figure 10-10. Continuous Read Mode Accesses ...................................................................... 503 12 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Figure 10-11. Figure 10-12. Figure 10-13. Figure 10-14. Figure 10-15. Figure 10-16. Figure 10-17. Figure 10-18. Figure 10-19. Figure 10-20. Figure 10-21. Figure 10-22. Figure 10-23. Figure 10-24. Figure 11-1. Figure 11-2. Figure 11-3. Figure 11-4. Figure 11-5. Figure 12-1. Figure 13-1. Figure 13-2. Figure 13-3. Figure 13-4. Figure 13-5. Figure 13-6. Figure 13-7. Figure 13-8. Figure 13-9. Figure 13-10. Figure 13-11. Figure 13-12. Figure 13-13. Figure 13-14. Figure 13-15. Figure 13-16. Figure 13-17. Figure 14-1. Figure 14-2. Figure 14-3. Figure 14-4. Figure 14-5. Figure 15-1. Figure 15-2. Figure 15-3. Figure 15-4. Figure 15-5. Write Followed by Read to External FIFO ............................................................ 504 Two-Entry FIFO ................................................................................................. 504 Single-Cycle Write Access, FRM50=0, FRMCNT=0, WRCYC=0 ........................... 508 Two-Cycle Read, Write Accesses, FRM50=0, FRMCNT=0, RDCYC=1, WRCYC=1 ........................................................................................................ 508 Read Accesses, FRM50=0, FRMCNT=0, RDCYC=1 ............................................ 509 FRAME Signal Operation, FRM50=0 and FRMCNT=0 ......................................... 509 FRAME Signal Operation, FRM50=0 and FRMCNT=1 ......................................... 509 FRAME Signal Operation, FRM50=0 and FRMCNT=2 ......................................... 510 FRAME Signal Operation, FRM50=1 and FRMCNT=0 ......................................... 510 FRAME Signal Operation, FRM50=1 and FRMCNT=1 ......................................... 510 FRAME Signal Operation, FRM50=1 and FRMCNT=2 ......................................... 510 iRDY Signal Operation, FRM50=0, FRMCNT=0, and RD2CYC=1 ......................... 511 EPI Clock Operation, CLKGATE=1, WR2CYC=0 ................................................. 512 EPI Clock Operation, CLKGATE=1, WR2CYC=1 ................................................. 512 GPTM Module Block Diagram ............................................................................ 558 Timer Daisy Chain ............................................................................................. 563 Input Edge-Count Mode Example ....................................................................... 565 16-Bit Input Edge-Time Mode Example ............................................................... 567 16-Bit PWM Mode Example ................................................................................ 568 WDT Module Block Diagram .............................................................................. 605 Implementation of Two ADC Blocks .................................................................... 630 ADC Module Block Diagram ............................................................................... 631 ADC Sample Phases ......................................................................................... 635 Doubling the ADC Sample Rate .......................................................................... 635 Skewed Sampling .............................................................................................. 636 Sample Averaging Example ............................................................................... 637 ADC Input Equivalency Diagram ......................................................................... 638 Internal Voltage Conversion Result ..................................................................... 639 External Voltage Conversion Result with 3.0-V Setting ......................................... 640 External Voltage Conversion Result with 1.0-V Setting ......................................... 640 Differential Sampling Range, VIN_ODD = 1.5 V ...................................................... 642 Differential Sampling Range, VIN_ODD = 0.75 V .................................................... 642 Differential Sampling Range, VIN_ODD = 2.25 V .................................................... 643 Internal Temperature Sensor Characteristic ......................................................... 644 Low-Band Operation (CIC=0x0) .......................................................................... 646 Mid-Band Operation (CIC=0x1) .......................................................................... 647 High-Band Operation (CIC=0x3) ......................................................................... 648 UART Module Block Diagram ............................................................................. 710 UART Character Frame ..................................................................................... 713 IrDA Data Modulation ......................................................................................... 715 LIN Message ..................................................................................................... 717 LIN Synchronization Field ................................................................................... 718 SSI Module Block Diagram ................................................................................. 774 TI Synchronous Serial Frame Format (Single Transfer) ........................................ 778 TI Synchronous Serial Frame Format (Continuous Transfer) ................................ 778 Freescale SPI Format (Single Transfer) with SPO=0 and SPH=0 .......................... 779 Freescale SPI Format (Continuous Transfer) with SPO=0 and SPH=0 .................. 779 July 03, 2014 13 Texas Instruments-Production Data Table of Contents Figure 15-6. Figure 15-7. Figure 15-8. Figure 15-9. Figure 15-10. Figure 15-11. Figure 15-12. Figure 16-1. Figure 16-2. Figure 16-3. Figure 16-4. Figure 16-5. Figure 16-6. Figure 16-7. Figure 16-8. Figure 16-9. Figure 16-10. Figure 16-11. Freescale SPI Frame Format with SPO=0 and SPH=1 ......................................... 780 Freescale SPI Frame Format (Single Transfer) with SPO=1 and SPH=0 ............... 781 Freescale SPI Frame Format (Continuous Transfer) with SPO=1 and SPH=0 ........ 781 Freescale SPI Frame Format with SPO=1 and SPH=1 ......................................... 782 MICROWIRE Frame Format (Single Frame) ........................................................ 783 MICROWIRE Frame Format (Continuous Transfer) ............................................. 784 MICROWIRE Frame Format, SSIFss Input Setup and Hold Requirements ............ 784 I2C Block Diagram ............................................................................................. 816 I2C Bus Configuration ........................................................................................ 817 START and STOP Conditions ............................................................................. 818 Complete Data Transfer with a 7-Bit Address ....................................................... 818 R/S Bit in First Byte ............................................................................................ 819 Data Validity During Bit Transfer on the I2C Bus ................................................... 819 Master Single TRANSMIT .................................................................................. 823 Master Single RECEIVE ..................................................................................... 824 Master TRANSMIT with Repeated START ........................................................... 825 Master RECEIVE with Repeated START ............................................................. 826 Master RECEIVE with Repeated START after TRANSMIT with Repeated START .............................................................................................................. 827 Figure 16-12. Master TRANSMIT with Repeated START after RECEIVE with Repeated START .............................................................................................................. 828 Figure 16-13. Slave Command Sequence ................................................................................ 829 Figure 17-1. I2S Block Diagram ............................................................................................. 854 Figure 17-2. I2S Data Transfer ............................................................................................... 857 Figure 17-3. Left-Justified Data Transfer ................................................................................ 857 Figure 17-4. Right-Justified Data Transfer .............................................................................. 857 Figure 18-1. CAN Controller Block Diagram ............................................................................ 891 Figure 18-2. CAN Data/Remote Frame .................................................................................. 893 Figure 18-3. Message Objects in a FIFO Buffer ...................................................................... 901 Figure 18-4. CAN Bit Time .................................................................................................... 905 Figure 19-1. Ethernet Controller ............................................................................................. 942 Figure 19-2. Ethernet Controller Block Diagram ...................................................................... 942 Figure 19-3. Ethernet Frame ................................................................................................. 944 Figure 19-4. Interface to an Ethernet Jack .............................................................................. 951 Figure 20-1. USB Module Block Diagram ............................................................................. 1001 Figure 21-1. Analog Comparator Module Block Diagram ....................................................... 1140 Figure 21-2. Structure of Comparator Unit ............................................................................ 1142 Figure 21-3. Comparator Internal Reference Structure .......................................................... 1142 Figure 22-1. 100-Pin LQFP Package Pin Diagram ................................................................ 1153 Figure 22-2. 108-Ball BGA Package Pin Diagram (Top View) ................................................. 1154 Figure 25-1. Load Conditions ............................................................................................... 1223 Figure 25-2. JTAG Test Clock Input Timing ........................................................................... 1224 Figure 25-3. JTAG Test Access Port (TAP) Timing ................................................................ 1224 Figure 25-4. Power-On Reset Timing ................................................................................... 1225 Figure 25-5. Brown-Out Reset Timing .................................................................................. 1225 Figure 25-6. Power-On Reset and Voltage Parameters ......................................................... 1226 Figure 25-7. External Reset Timing (RST) ............................................................................ 1226 Figure 25-8. Software Reset Timing ..................................................................................... 1226 14 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Figure 25-9. Figure 25-10. Figure 25-11. Figure 25-12. Figure 25-13. Figure 25-14. Figure 25-15. Figure 25-16. Figure 25-17. Figure 25-18. Figure 25-19. Figure 25-20. Figure 25-21. Figure 25-22. Figure 25-23. Figure 25-24. Figure 25-25. Figure 25-26. Figure 25-27. Figure 25-28. Figure 25-29. Figure 25-30. Figure 25-31. Figure C-1. Figure C-2. Figure C-3. Figure C-4. Figure C-5. Figure C-6. Watchdog Reset Timing ................................................................................... 1227 MOSC Failure Reset Timing ............................................................................. 1227 Hibernation Module Timing with Internal Oscillator Running in Hibernation .......... 1232 Hibernation Module Timing with Internal Oscillator Stopped in Hibernation .......... 1232 SDRAM Initialization and Load Mode Register Timing ........................................ 1234 SDRAM Read Timing ....................................................................................... 1234 SDRAM Write Timing ....................................................................................... 1235 Host-Bus 8/16 Mode Read Timing ..................................................................... 1236 Host-Bus 8/16 Mode Write Timing ..................................................................... 1236 Host-Bus 8/16 Mode Muxed Read Timing .......................................................... 1237 Host-Bus 8/16 Mode Muxed Write Timing .......................................................... 1237 General-Purpose Mode Read and Write Timing ................................................. 1238 General-Purpose Mode iRDY Timing ................................................................. 1238 ADC Input Equivalency Diagram ....................................................................... 1240 SSI Timing for TI Frame Format (FRF=01), Single Transfer Timing Measurement .................................................................................................. 1241 SSI Timing for MICROWIRE Frame Format (FRF=10), Single Transfer ............... 1241 SSI Timing for SPI Frame Format (FRF=00), with SPH=1 ................................... 1242 I2C Timing ....................................................................................................... 1243 I2S Master Mode Transmit Timing ..................................................................... 1243 I2S Master Mode Receive Timing ...................................................................... 1244 I2S Slave Mode Transmit Timing ....................................................................... 1244 I2S Slave Mode Receive Timing ........................................................................ 1244 External XTLP Oscillator Characteristics ........................................................... 1247 Stellaris LM3S9U90 100-Pin LQFP Package Dimensions ................................... 1304 100-Pin LQFP Tray Dimensions ........................................................................ 1306 100-Pin LQFP Tape and Reel Dimensions ......................................................... 1307 Stellaris LM3S9U90 108-Ball BGA Package Dimensions .................................... 1308 108-Ball BGA Tray Dimensions ......................................................................... 1310 108-Ball BGA Tape and Reel Dimensions .......................................................... 1311 July 03, 2014 15 Texas Instruments-Production Data Table of Contents List of Tables Table 1. Table 2. Table 2-1. Table 2-2. Table 2-3. Table 2-4. Table 2-5. Table 2-6. Table 2-7. Table 2-8. Table 2-9. Table 2-10. Table 2-11. Table 2-12. Table 2-13. Table 3-1. Table 3-2. Table 3-3. Table 3-4. Table 3-5. Table 3-6. Table 3-7. Table 3-8. Table 3-9. Table 4-1. Table 4-2. Table 4-3. Table 4-4. Table 5-1. Table 5-2. Table 5-3. Table 5-4. Table 5-5. Table 5-6. Table 5-7. Table 5-8. Table 5-9. Table 6-1. Table 6-2. Table 6-3. Table 6-4. Table 7-1. Table 7-2. Table 7-3. Table 8-1. Table 8-2. Revision History .................................................................................................. 40 Documentation Conventions ................................................................................ 44 Summary of Processor Mode, Privilege Level, and Stack Use ................................ 73 Processor Register Map ....................................................................................... 74 PSR Register Combinations ................................................................................. 79 Memory Map ....................................................................................................... 87 Memory Access Behavior ..................................................................................... 90 SRAM Memory Bit-Banding Regions .................................................................... 92 Peripheral Memory Bit-Banding Regions ............................................................... 92 Exception Types .................................................................................................. 98 Interrupts ............................................................................................................ 99 Exception Return Behavior ................................................................................. 104 Faults ............................................................................................................... 104 Fault Status and Fault Address Registers ............................................................ 106 Cortex-M3 Instruction Summary ......................................................................... 108 Core Peripheral Register Regions ....................................................................... 111 Memory Attributes Summary .............................................................................. 114 TEX, S, C, and B Bit Field Encoding ................................................................... 117 Cache Policy for Memory Attribute Encoding ....................................................... 118 AP Bit Field Encoding ........................................................................................ 118 Memory Region Attributes for Stellaris Microcontrollers ........................................ 118 Peripherals Register Map ................................................................................... 119 Interrupt Priority Levels ...................................................................................... 146 Example SIZE Field Values ................................................................................ 174 JTAG_SWD_SWO Signals (100LQFP) ................................................................ 178 JTAG_SWD_SWO Signals (108BGA) ................................................................. 179 JTAG Port Pins State after Power-On Reset or RST assertion .............................. 180 JTAG Instruction Register Commands ................................................................. 185 System Control & Clocks Signals (100LQFP) ...................................................... 189 System Control & Clocks Signals (108BGA) ........................................................ 189 Reset Sources ................................................................................................... 190 Clock Source Options ........................................................................................ 197 Possible System Clock Frequencies Using the SYSDIV Field ............................... 200 Examples of Possible System Clock Frequencies Using the SYSDIV2 Field .......... 200 Examples of Possible System Clock Frequencies with DIV400=1 ......................... 201 System Control Register Map ............................................................................. 206 RCC2 Fields that Override RCC Fields ............................................................... 226 Hibernate Signals (100LQFP) ............................................................................. 294 Hibernate Signals (108BGA) .............................................................................. 295 Hibernation Module Clock Operation ................................................................... 301 Hibernation Module Register Map ....................................................................... 303 Flash Memory Protection Policy Combinations .................................................... 324 User-Programmable Flash Memory Resident Registers ....................................... 328 Flash Register Map ............................................................................................ 328 μDMA Channel Assignments .............................................................................. 368 Request Type Support ....................................................................................... 370 16 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Table 8-3. Table 8-4. Table 8-5. Table 8-6. Table 8-7. Table 8-8. Table 8-9. Table 8-10. Table 8-11. Table 8-12. Table 8-13. Table 9-1. Table 9-2. Table 9-3. Table 9-4. Table 9-5. Table 9-6. Table 9-7. Table 9-8. Table 9-9. Table 9-10. Table 9-11. Table 9-12. Table 10-1. Table 10-2. Table 10-3. Table 10-4. Table 10-5. Table 10-6. Table 10-7. Table 10-8. Table 11-1. Table 11-2. Table 11-3. Table 11-4. Table 11-5. Table 11-6. Table 11-7. Table 11-8. Table 11-9. Table 11-10. Table 11-11. Table 12-1. Table 13-1. Table 13-2. Table 13-3. Table 13-4. Control Structure Memory Map ........................................................................... 371 Channel Control Structure .................................................................................. 371 μDMA Read Example: 8-Bit Peripheral ................................................................ 381 μDMA Interrupt Assignments .............................................................................. 382 Channel Control Structure Offsets for Channel 30 ................................................ 383 Channel Control Word Configuration for Memory Transfer Example ...................... 383 Channel Control Structure Offsets for Channel 7 .................................................. 384 Channel Control Word Configuration for Peripheral Transmit Example .................. 385 Primary and Alternate Channel Control Structure Offsets for Channel 8 ................. 386 Channel Control Word Configuration for Peripheral Ping-Pong Receive Example ............................................................................................................ 387 μDMA Register Map .......................................................................................... 389 GPIO Pins With Non-Zero Reset Values .............................................................. 428 GPIO Pins and Alternate Functions (100LQFP) ................................................... 428 GPIO Pins and Alternate Functions (108BGA) ..................................................... 430 GPIO Pad Configuration Examples ..................................................................... 436 GPIO Interrupt Configuration Example ................................................................ 437 GPIO Pins With Non-Zero Reset Values .............................................................. 438 GPIO Register Map ........................................................................................... 438 GPIO Pins With Non-Zero Reset Values .............................................................. 450 GPIO Pins With Non-Zero Reset Values .............................................................. 456 GPIO Pins With Non-Zero Reset Values .............................................................. 458 GPIO Pins With Non-Zero Reset Values .............................................................. 461 GPIO Pins With Non-Zero Reset Values .............................................................. 468 External Peripheral Interface Signals (100LQFP) ................................................. 484 External Peripheral Interface Signals (108BGA) ................................................... 485 EPI SDRAM Signal Connections ......................................................................... 490 Capabilities of Host Bus 8 and Host Bus 16 Modes .............................................. 494 EPI Host-Bus 8 Signal Connections .................................................................... 495 EPI Host-Bus 16 Signal Connections .................................................................. 497 EPI General Purpose Signal Connections ........................................................... 506 External Peripheral Interface (EPI) Register Map ................................................. 512 Available CCP Pins ............................................................................................ 558 General-Purpose Timers Signals (100LQFP) ....................................................... 559 General-Purpose Timers Signals (108BGA) ......................................................... 560 General-Purpose Timer Capabilities .................................................................... 561 Counter Values When the Timer is Enabled in Periodic or One-Shot Modes .......... 562 16-Bit Timer With Prescaler Configurations ......................................................... 563 Counter Values When the Timer is Enabled in RTC Mode .................................... 564 Counter Values When the Timer is Enabled in Input Edge-Count Mode ................. 564 Counter Values When the Timer is Enabled in Input Event-Count Mode ................ 566 Counter Values When the Timer is Enabled in PWM Mode ................................... 567 Timers Register Map .......................................................................................... 572 Watchdog Timers Register Map .......................................................................... 607 ADC Signals (100LQFP) .................................................................................... 631 ADC Signals (108BGA) ...................................................................................... 632 Samples and FIFO Depth of Sequencers ............................................................ 633 Differential Sampling Pairs ................................................................................. 641 July 03, 2014 17 Texas Instruments-Production Data Table of Contents Table 13-5. Table 14-1. Table 14-2. Table 14-3. Table 14-4. Table 15-1. Table 15-2. Table 15-3. Table 16-1. Table 16-2. Table 16-3. Table 16-4. Table 16-5. Table 17-1. Table 17-2. Table 17-3. Table 17-4. Table 17-5. Table 17-6. Table 17-7. Table 17-8. Table 17-9. Table 17-10. Table 18-1. Table 18-2. Table 18-3. Table 18-4. Table 18-5. Table 18-6. Table 19-1. Table 19-2. Table 19-3. Table 19-4. Table 20-1. Table 20-2. Table 20-3. Table 20-4. Table 20-5. Table 20-6. Table 21-1. Table 21-2. Table 21-3. Table 21-4. Table 23-1. Table 23-2. Table 23-3. Table 23-4. Table 23-5. ADC Register Map ............................................................................................. 649 UART Signals (100LQFP) .................................................................................. 711 UART Signals (108BGA) .................................................................................... 711 Flow Control Mode ............................................................................................. 716 UART Register Map ........................................................................................... 722 SSI Signals (100LQFP) ...................................................................................... 775 SSI Signals (108BGA) ........................................................................................ 775 SSI Register Map .............................................................................................. 786 I2C Signals (100LQFP) ...................................................................................... 816 I2C Signals (108BGA) ........................................................................................ 816 Examples of I2C Master Timer Period versus Speed Mode ................................... 820 Inter-Integrated Circuit (I2C) Interface Register Map ............................................. 830 Write Field Decoding for I2CMCS[3:0] Field ......................................................... 836 I2S Signals (100LQFP) ...................................................................................... 855 I2S Signals (108BGA) ........................................................................................ 855 I2S Transmit FIFO Interface ................................................................................ 858 Crystal Frequency (Values from 3.5795 MHz to 5 MHz) ........................................ 859 Crystal Frequency (Values from 5.12 MHz to 8.192 MHz) ..................................... 859 Crystal Frequency (Values from 10 MHz to 14.3181 MHz) .................................... 860 Crystal Frequency (Values from 16 MHz to 16.384 MHz) ...................................... 860 I2S Receive FIFO Interface ................................................................................. 862 Audio Formats Configuration .............................................................................. 864 Inter-Integrated Circuit Sound (I2S) Interface Register Map ................................... 865 Controller Area Network Signals (100LQFP) ........................................................ 892 Controller Area Network Signals (108BGA) ......................................................... 892 Message Object Configurations .......................................................................... 898 CAN Protocol Ranges ........................................................................................ 905 CANBIT Register Values .................................................................................... 905 CAN Register Map ............................................................................................. 909 Ethernet Signals (100LQFP) ............................................................................... 943 Ethernet Signals (108BGA) ................................................................................ 943 TX & RX FIFO Organization ............................................................................... 946 Ethernet Register Map ....................................................................................... 953 USB Signals (100LQFP) ................................................................................... 1002 USB Signals (108BGA) .................................................................................... 1002 Remainder (MAXLOAD/4) ................................................................................ 1014 Actual Bytes Read ........................................................................................... 1014 Packet Sizes That Clear RXRDY ...................................................................... 1015 Universal Serial Bus (USB) Controller Register Map ........................................... 1016 Analog Comparators Signals (100LQFP) ........................................................... 1140 Analog Comparators Signals (108BGA) ............................................................. 1141 Internal Reference Voltage and ACREFCTL Field Values ................................... 1143 Analog Comparators Register Map ................................................................... 1144 GPIO Pins With Default Alternate Functions ...................................................... 1155 Signals by Pin Number ..................................................................................... 1156 Signals by Signal Name ................................................................................... 1165 Signals by Function, Except for GPIO ............................................................... 1174 GPIO Pins and Alternate Functions ................................................................... 1181 18 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Table 23-6. Table 23-7. Table 23-8. Table 23-9. Table 23-10. Table 23-11. Table 23-12. Table 23-13. Table 24-1. Table 24-2. Table 24-3. Table 25-1. Table 25-2. Table 25-3. Table 25-4. Table 25-5. Table 25-6. Table 25-7. Table 25-8. Table 25-9. Table 25-10. Table 25-11. Table 25-12. Table 25-13. Table 25-14. Table 25-15. Table 25-16. Table 25-17. Table 25-18. Table 25-19. Table 25-20. Table 25-21. Table 25-22. Table 25-23. Table 25-24. Table 25-25. Table 25-26. Table 25-27. Table 25-28. Table 25-29. Table 25-30. Table 25-31. Table 25-32. Table 25-33. Table 25-34. Table 25-35. Table 25-36. Table 25-37. Possible Pin Assignments for Alternate Functions .............................................. 1184 Signals by Pin Number ..................................................................................... 1187 Signals by Signal Name ................................................................................... 1197 Signals by Function, Except for GPIO ............................................................... 1206 GPIO Pins and Alternate Functions ................................................................... 1213 Possible Pin Assignments for Alternate Functions .............................................. 1216 Connections for Unused Signals (100-Pin LQFP) ............................................... 1219 Connections for Unused Signals (108-Ball BGA) ................................................ 1220 Temperature Characteristics ............................................................................. 1221 Thermal Characteristics ................................................................................... 1221 ESD Absolute Maximum Ratings ...................................................................... 1221 Maximum Ratings ............................................................................................ 1222 Recommended DC Operating Conditions .......................................................... 1222 JTAG Characteristics ....................................................................................... 1223 Power Characteristics ...................................................................................... 1225 Reset Characteristics ....................................................................................... 1226 LDO Regulator Characteristics ......................................................................... 1227 Phase Locked Loop (PLL) Characteristics ......................................................... 1227 Actual PLL Frequency ...................................................................................... 1228 PIOSC Clock Characteristics ............................................................................ 1228 30-kHz Clock Characteristics ............................................................................ 1228 Hibernation Clock Characteristics ..................................................................... 1229 HIB Oscillator Input Characteristics ................................................................... 1229 Main Oscillator Clock Characteristics ................................................................ 1229 Supported MOSC Crystal Frequencies .............................................................. 1229 System Clock Characteristics with ADC Operation ............................................. 1230 System Clock Characteristics with USB Operation ............................................. 1230 Sleep Modes AC Characteristics ....................................................................... 1230 Hibernation Module Battery Characteristics ....................................................... 1231 Hibernation Module AC Characteristics ............................................................. 1231 Flash Memory Characteristics ........................................................................... 1232 GPIO Module Characteristics ............................................................................ 1232 EPI SDRAM Characteristics ............................................................................. 1233 EPI SDRAM Interface Characteristics ............................................................... 1233 EPI Host-Bus 8 and Host-Bus 16 Interface Characteristics ................................. 1235 EPI General-Purpose Interface Characteristics .................................................. 1237 ADC Characteristics ......................................................................................... 1239 ADC Module External Reference Characteristics ............................................... 1240 ADC Module Internal Reference Characteristics ................................................ 1240 SSI Characteristics .......................................................................................... 1240 I2C Characteristics ........................................................................................... 1242 I2S Master Clock (Receive and Transmit) .......................................................... 1243 I2S Slave Clock (Receive and Transmit) ............................................................ 1243 I2S Master Mode .............................................................................................. 1243 I2S Slave Mode ................................................................................................ 1244 Ethernet Controller DC Characteristics .............................................................. 1244 100BASE-TX Transmitter Characteristics .......................................................... 1245 100BASE-TX Transmitter Characteristics (informative) ....................................... 1245 July 03, 2014 19 Texas Instruments-Production Data Table of Contents Table 25-38. Table 25-39. Table 25-40. Table 25-41. Table 25-42. Table 25-43. Table 25-44. Table 25-45. Table 25-46. Table 25-47. Table 25-48. Table 25-49. Table 25-50. 100BASE-TX Receiver Characteristics .............................................................. 10BASE-T Transmitter Characteristics .............................................................. 10BASE-T Transmitter Characteristics (informative) ........................................... 10BASE-T Receiver Characteristics .................................................................. Isolation Transformers ...................................................................................... Ethernet Reference Crystal .............................................................................. External XTLP Oscillator Characteristics ........................................................... USB Controller Characteristics ......................................................................... Analog Comparator Characteristics ................................................................... Analog Comparator Voltage Reference Characteristics ...................................... Nominal Power Consumption ........................................................................... Detailed Current Specifications ......................................................................... Hibernation Detailed Current Specifications ....................................................... 20 1245 1245 1245 1246 1246 1246 1247 1247 1247 1248 1248 1249 1250 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller List of Registers The Cortex-M3 Processor ............................................................................................................. 68 Register 1: Register 2: Register 3: Register 4: Register 5: Register 6: Register 7: Register 8: Register 9: Register 10: Register 11: Register 12: Register 13: Register 14: Register 15: Register 16: Register 17: Register 18: Register 19: Register 20: Register 21: Cortex General-Purpose Register 0 (R0) ........................................................................... 75 Cortex General-Purpose Register 1 (R1) ........................................................................... 75 Cortex General-Purpose Register 2 (R2) ........................................................................... 75 Cortex General-Purpose Register 3 (R3) ........................................................................... 75 Cortex General-Purpose Register 4 (R4) ........................................................................... 75 Cortex General-Purpose Register 5 (R5) ........................................................................... 75 Cortex General-Purpose Register 6 (R6) ........................................................................... 75 Cortex General-Purpose Register 7 (R7) ........................................................................... 75 Cortex General-Purpose Register 8 (R8) ........................................................................... 75 Cortex General-Purpose Register 9 (R9) ........................................................................... 75 Cortex General-Purpose Register 10 (R10) ....................................................................... 75 Cortex General-Purpose Register 11 (R11) ........................................................................ 75 Cortex General-Purpose Register 12 (R12) ....................................................................... 75 Stack Pointer (SP) ........................................................................................................... 76 Link Register (LR) ............................................................................................................ 77 Program Counter (PC) ..................................................................................................... 78 Program Status Register (PSR) ........................................................................................ 79 Priority Mask Register (PRIMASK) .................................................................................... 83 Fault Mask Register (FAULTMASK) .................................................................................. 84 Base Priority Mask Register (BASEPRI) ............................................................................ 85 Control Register (CONTROL) ........................................................................................... 86 Cortex-M3 Peripherals ................................................................................................................. 111 Register 1: Register 2: Register 3: Register 4: Register 5: Register 6: Register 7: Register 8: Register 9: Register 10: Register 11: Register 12: Register 13: Register 14: Register 15: Register 16: Register 17: Register 18: Register 19: Register 20: Register 21: Register 22: SysTick Control and Status Register (STCTRL), offset 0x010 ........................................... 122 SysTick Reload Value Register (STRELOAD), offset 0x014 .............................................. 124 SysTick Current Value Register (STCURRENT), offset 0x018 ........................................... 125 Interrupt 0-31 Set Enable (EN0), offset 0x100 .................................................................. 126 Interrupt 32-54 Set Enable (EN1), offset 0x104 ................................................................ 127 Interrupt 0-31 Clear Enable (DIS0), offset 0x180 .............................................................. 128 Interrupt 32-54 Clear Enable (DIS1), offset 0x184 ............................................................ 129 Interrupt 0-31 Set Pending (PEND0), offset 0x200 ........................................................... 130 Interrupt 32-54 Set Pending (PEND1), offset 0x204 ......................................................... 131 Interrupt 0-31 Clear Pending (UNPEND0), offset 0x280 ................................................... 132 Interrupt 32-54 Clear Pending (UNPEND1), offset 0x284 .................................................. 133 Interrupt 0-31 Active Bit (ACTIVE0), offset 0x300 ............................................................. 134 Interrupt 32-54 Active Bit (ACTIVE1), offset 0x304 ........................................................... 135 Interrupt 0-3 Priority (PRI0), offset 0x400 ......................................................................... 136 Interrupt 4-7 Priority (PRI1), offset 0x404 ......................................................................... 136 Interrupt 8-11 Priority (PRI2), offset 0x408 ....................................................................... 136 Interrupt 12-15 Priority (PRI3), offset 0x40C .................................................................... 136 Interrupt 16-19 Priority (PRI4), offset 0x410 ..................................................................... 136 Interrupt 20-23 Priority (PRI5), offset 0x414 ..................................................................... 136 Interrupt 24-27 Priority (PRI6), offset 0x418 ..................................................................... 136 Interrupt 28-31 Priority (PRI7), offset 0x41C .................................................................... 136 Interrupt 32-35 Priority (PRI8), offset 0x420 ..................................................................... 136 July 03, 2014 21 Texas Instruments-Production Data Table of Contents Register 23: Register 24: Register 25: Register 26: Register 27: Register 28: Register 29: Register 30: Register 31: Register 32: Register 33: Register 34: Register 35: Register 36: Register 37: Register 38: Register 39: Register 40: Register 41: Register 42: Register 43: Register 44: Register 45: Register 46: Register 47: Register 48: Register 49: Register 50: Register 51: Register 52: Register 53: Register 54: Interrupt 36-39 Priority (PRI9), offset 0x424 ..................................................................... 136 Interrupt 40-43 Priority (PRI10), offset 0x428 ................................................................... 136 Interrupt 44-47 Priority (PRI11), offset 0x42C ................................................................... 136 Interrupt 48-51 Priority (PRI12), offset 0x430 ................................................................... 136 Interrupt 52-54 Priority (PRI13), offset 0x434 ................................................................... 136 Software Trigger Interrupt (SWTRIG), offset 0xF00 .......................................................... 138 Auxiliary Control (ACTLR), offset 0x008 .......................................................................... 139 CPU ID Base (CPUID), offset 0xD00 ............................................................................... 141 Interrupt Control and State (INTCTRL), offset 0xD04 ........................................................ 142 Vector Table Offset (VTABLE), offset 0xD08 .................................................................... 145 Application Interrupt and Reset Control (APINT), offset 0xD0C ......................................... 146 System Control (SYSCTRL), offset 0xD10 ....................................................................... 148 Configuration and Control (CFGCTRL), offset 0xD14 ....................................................... 150 System Handler Priority 1 (SYSPRI1), offset 0xD18 ......................................................... 152 System Handler Priority 2 (SYSPRI2), offset 0xD1C ........................................................ 153 System Handler Priority 3 (SYSPRI3), offset 0xD20 ......................................................... 154 System Handler Control and State (SYSHNDCTRL), offset 0xD24 .................................... 155 Configurable Fault Status (FAULTSTAT), offset 0xD28 ..................................................... 159 Hard Fault Status (HFAULTSTAT), offset 0xD2C .............................................................. 165 Memory Management Fault Address (MMADDR), offset 0xD34 ........................................ 166 Bus Fault Address (FAULTADDR), offset 0xD38 .............................................................. 167 MPU Type (MPUTYPE), offset 0xD90 ............................................................................. 168 MPU Control (MPUCTRL), offset 0xD94 .......................................................................... 169 MPU Region Number (MPUNUMBER), offset 0xD98 ....................................................... 171 MPU Region Base Address (MPUBASE), offset 0xD9C ................................................... 172 MPU Region Base Address Alias 1 (MPUBASE1), offset 0xDA4 ....................................... 172 MPU Region Base Address Alias 2 (MPUBASE2), offset 0xDAC ...................................... 172 MPU Region Base Address Alias 3 (MPUBASE3), offset 0xDB4 ....................................... 172 MPU Region Attribute and Size (MPUATTR), offset 0xDA0 ............................................... 174 MPU Region Attribute and Size Alias 1 (MPUATTR1), offset 0xDA8 .................................. 174 MPU Region Attribute and Size Alias 2 (MPUATTR2), offset 0xDB0 .................................. 174 MPU Region Attribute and Size Alias 3 (MPUATTR3), offset 0xDB8 .................................. 174 System Control ............................................................................................................................ 189 Register 1: Register 2: Register 3: Register 4: Register 5: Register 6: Register 7: Register 8: Register 9: Register 10: Register 11: Register 12: Register 13: Register 14: Register 15: Device Identification 0 (DID0), offset 0x000 ..................................................................... 208 Brown-Out Reset Control (PBORCTL), offset 0x030 ........................................................ 210 Raw Interrupt Status (RIS), offset 0x050 .......................................................................... 211 Interrupt Mask Control (IMC), offset 0x054 ...................................................................... 213 Masked Interrupt Status and Clear (MISC), offset 0x058 .................................................. 215 Reset Cause (RESC), offset 0x05C ................................................................................ 217 Run-Mode Clock Configuration (RCC), offset 0x060 ......................................................... 219 XTAL to PLL Translation (PLLCFG), offset 0x064 ............................................................. 223 GPIO High-Performance Bus Control (GPIOHBCTL), offset 0x06C ................................... 224 Run-Mode Clock Configuration 2 (RCC2), offset 0x070 .................................................... 226 Main Oscillator Control (MOSCCTL), offset 0x07C ........................................................... 229 Deep Sleep Clock Configuration (DSLPCLKCFG), offset 0x144 ........................................ 230 Precision Internal Oscillator Calibration (PIOSCCAL), offset 0x150 ................................... 232 Precision Internal Oscillator Statistics (PIOSCSTAT), offset 0x154 .................................... 234 I2S MCLK Configuration (I2SMCLKCFG), offset 0x170 ..................................................... 235 22 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 16: Register 17: Register 18: Register 19: Register 20: Register 21: Register 22: Register 23: Register 24: Register 25: Register 26: Register 27: Register 28: Register 29: Register 30: Register 31: Register 32: Register 33: Register 34: Register 35: Register 36: Register 37: Register 38: Register 39: Device Identification 1 (DID1), offset 0x004 ..................................................................... 237 Device Capabilities 0 (DC0), offset 0x008 ........................................................................ 239 Device Capabilities 1 (DC1), offset 0x010 ........................................................................ 240 Device Capabilities 2 (DC2), offset 0x014 ........................................................................ 242 Device Capabilities 3 (DC3), offset 0x018 ........................................................................ 244 Device Capabilities 4 (DC4), offset 0x01C ....................................................................... 246 Device Capabilities 5 (DC5), offset 0x020 ........................................................................ 248 Device Capabilities 6 (DC6), offset 0x024 ........................................................................ 249 Device Capabilities 7 (DC7), offset 0x028 ........................................................................ 250 Device Capabilities 8 ADC Channels (DC8), offset 0x02C ................................................ 254 Device Capabilities 9 ADC Digital Comparators (DC9), offset 0x190 ................................. 257 Non-Volatile Memory Information (NVMSTAT), offset 0x1A0 ............................................. 259 Run Mode Clock Gating Control Register 0 (RCGC0), offset 0x100 ................................... 260 Sleep Mode Clock Gating Control Register 0 (SCGC0), offset 0x110 ................................. 263 Deep Sleep Mode Clock Gating Control Register 0 (DCGC0), offset 0x120 ....................... 266 Run Mode Clock Gating Control Register 1 (RCGC1), offset 0x104 ................................... 268 Sleep Mode Clock Gating Control Register 1 (SCGC1), offset 0x114 ................................. 271 Deep-Sleep Mode Clock Gating Control Register 1 (DCGC1), offset 0x124 ....................... 274 Run Mode Clock Gating Control Register 2 (RCGC2), offset 0x108 ................................... 277 Sleep Mode Clock Gating Control Register 2 (SCGC2), offset 0x118 ................................. 280 Deep Sleep Mode Clock Gating Control Register 2 (DCGC2), offset 0x128 ....................... 283 Software Reset Control 0 (SRCR0), offset 0x040 ............................................................. 286 Software Reset Control 1 (SRCR1), offset 0x044 ............................................................. 288 Software Reset Control 2 (SRCR2), offset 0x048 ............................................................. 291 Hibernation Module ..................................................................................................................... 293 Register 1: Register 2: Register 3: Register 4: Register 5: Register 6: Register 7: Register 8: Register 9: Register 10: Register 11: Hibernation RTC Counter (HIBRTCC), offset 0x000 ......................................................... Hibernation RTC Match 0 (HIBRTCM0), offset 0x004 ....................................................... Hibernation RTC Match 1 (HIBRTCM1), offset 0x008 ....................................................... Hibernation RTC Load (HIBRTCLD), offset 0x00C ........................................................... Hibernation Control (HIBCTL), offset 0x010 ..................................................................... Hibernation Interrupt Mask (HIBIM), offset 0x014 ............................................................. Hibernation Raw Interrupt Status (HIBRIS), offset 0x018 .................................................. Hibernation Masked Interrupt Status (HIBMIS), offset 0x01C ............................................ Hibernation Interrupt Clear (HIBIC), offset 0x020 ............................................................. Hibernation RTC Trim (HIBRTCT), offset 0x024 ............................................................... Hibernation Data (HIBDATA), offset 0x030-0x12C ............................................................ 304 305 306 307 308 311 313 315 317 318 319 Internal Memory ........................................................................................................................... 320 Register 1: Register 2: Register 3: Register 4: Register 5: Register 6: Register 7: Register 8: Register 9: Register 10: Register 11: Flash Memory Address (FMA), offset 0x000 .................................................................... 331 Flash Memory Data (FMD), offset 0x004 ......................................................................... 332 Flash Memory Control (FMC), offset 0x008 ..................................................................... 333 Flash Controller Raw Interrupt Status (FCRIS), offset 0x00C ............................................ 336 Flash Controller Interrupt Mask (FCIM), offset 0x010 ........................................................ 337 Flash Controller Masked Interrupt Status and Clear (FCMISC), offset 0x014 ..................... 338 Flash Memory Control 2 (FMC2), offset 0x020 ................................................................. 339 Flash Write Buffer Valid (FWBVAL), offset 0x030 ............................................................. 340 Flash Control (FCTL), offset 0x0F8 ................................................................................. 341 Flash Write Buffer n (FWBn), offset 0x100 - 0x17C .......................................................... 342 ROM Control (RMCTL), offset 0x0F0 .............................................................................. 343 July 03, 2014 23 Texas Instruments-Production Data Table of Contents Register 12: Register 13: Register 14: Register 15: Register 16: Register 17: Register 18: Register 19: Register 20: Register 21: Register 22: Register 23: Register 24: Register 25: Register 26: Register 27: Register 28: Register 29: Register 30: Register 31: Register 32: Flash Memory Protection Read Enable 0 (FMPRE0), offset 0x130 and 0x200 ................... 344 Flash Memory Protection Program Enable 0 (FMPPE0), offset 0x134 and 0x400 ............... 345 Boot Configuration (BOOTCFG), offset 0x1D0 ................................................................. 346 User Register 0 (USER_REG0), offset 0x1E0 .................................................................. 348 User Register 1 (USER_REG1), offset 0x1E4 .................................................................. 349 User Register 2 (USER_REG2), offset 0x1E8 .................................................................. 350 User Register 3 (USER_REG3), offset 0x1EC ................................................................. 351 Flash Memory Protection Read Enable 1 (FMPRE1), offset 0x204 .................................... 352 Flash Memory Protection Read Enable 2 (FMPRE2), offset 0x208 .................................... 353 Flash Memory Protection Read Enable 3 (FMPRE3), offset 0x20C ................................... 354 Flash Memory Protection Read Enable 4 (FMPRE4), offset 0x210 .................................... 355 Flash Memory Protection Read Enable 5 (FMPRE5), offset 0x214 .................................... 356 Flash Memory Protection Read Enable 6 (FMPRE6), offset 0x218 .................................... 357 Flash Memory Protection Read Enable 7 (FMPRE7), offset 0x21C ................................... 358 Flash Memory Protection Program Enable 1 (FMPPE1), offset 0x404 ............................... 359 Flash Memory Protection Program Enable 2 (FMPPE2), offset 0x408 ............................... 360 Flash Memory Protection Program Enable 3 (FMPPE3), offset 0x40C ............................... 361 Flash Memory Protection Program Enable 4 (FMPPE4), offset 0x410 ............................... 362 Flash Memory Protection Program Enable 5 (FMPPE5), offset 0x414 ............................... 363 Flash Memory Protection Program Enable 6 (FMPPE6), offset 0x418 ............................... 364 Flash Memory Protection Program Enable 7 (FMPPE7), offset 0x41C ............................... 365 Micro Direct Memory Access (μDMA) ........................................................................................ 366 Register 1: Register 2: Register 3: Register 4: Register 5: Register 6: Register 7: Register 8: Register 9: Register 10: Register 11: Register 12: Register 13: Register 14: Register 15: Register 16: Register 17: Register 18: Register 19: Register 20: Register 21: Register 22: Register 23: Register 24: Register 25: Register 26: DMA Channel Source Address End Pointer (DMASRCENDP), offset 0x000 ...................... 391 DMA Channel Destination Address End Pointer (DMADSTENDP), offset 0x004 ................ 392 DMA Channel Control Word (DMACHCTL), offset 0x008 .................................................. 393 DMA Status (DMASTAT), offset 0x000 ............................................................................ 398 DMA Configuration (DMACFG), offset 0x004 ................................................................... 400 DMA Channel Control Base Pointer (DMACTLBASE), offset 0x008 .................................. 401 DMA Alternate Channel Control Base Pointer (DMAALTBASE), offset 0x00C .................... 402 DMA Channel Wait-on-Request Status (DMAWAITSTAT), offset 0x010 ............................. 403 DMA Channel Software Request (DMASWREQ), offset 0x014 ......................................... 404 DMA Channel Useburst Set (DMAUSEBURSTSET), offset 0x018 .................................... 405 DMA Channel Useburst Clear (DMAUSEBURSTCLR), offset 0x01C ................................. 406 DMA Channel Request Mask Set (DMAREQMASKSET), offset 0x020 .............................. 407 DMA Channel Request Mask Clear (DMAREQMASKCLR), offset 0x024 ........................... 408 DMA Channel Enable Set (DMAENASET), offset 0x028 ................................................... 409 DMA Channel Enable Clear (DMAENACLR), offset 0x02C ............................................... 410 DMA Channel Primary Alternate Set (DMAALTSET), offset 0x030 .................................... 411 DMA Channel Primary Alternate Clear (DMAALTCLR), offset 0x034 ................................. 412 DMA Channel Priority Set (DMAPRIOSET), offset 0x038 ................................................. 413 DMA Channel Priority Clear (DMAPRIOCLR), offset 0x03C .............................................. 414 DMA Bus Error Clear (DMAERRCLR), offset 0x04C ........................................................ 415 DMA Channel Assignment (DMACHASGN), offset 0x500 ................................................. 416 DMA Channel Interrupt Status (DMACHIS), offset 0x504 .................................................. 417 DMA Peripheral Identification 0 (DMAPeriphID0), offset 0xFE0 ......................................... 418 DMA Peripheral Identification 1 (DMAPeriphID1), offset 0xFE4 ......................................... 419 DMA Peripheral Identification 2 (DMAPeriphID2), offset 0xFE8 ......................................... 420 DMA Peripheral Identification 3 (DMAPeriphID3), offset 0xFEC ........................................ 421 24 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 27: Register 28: Register 29: Register 30: Register 31: DMA Peripheral Identification 4 (DMAPeriphID4), offset 0xFD0 ......................................... DMA PrimeCell Identification 0 (DMAPCellID0), offset 0xFF0 ........................................... DMA PrimeCell Identification 1 (DMAPCellID1), offset 0xFF4 ........................................... DMA PrimeCell Identification 2 (DMAPCellID2), offset 0xFF8 ........................................... DMA PrimeCell Identification 3 (DMAPCellID3), offset 0xFFC ........................................... 422 423 424 425 426 General-Purpose Input/Outputs (GPIOs) ................................................................................... 427 Register 1: Register 2: Register 3: Register 4: Register 5: Register 6: Register 7: Register 8: Register 9: Register 10: Register 11: Register 12: Register 13: Register 14: Register 15: Register 16: Register 17: Register 18: Register 19: Register 20: Register 21: Register 22: Register 23: Register 24: Register 25: Register 26: Register 27: Register 28: Register 29: Register 30: Register 31: Register 32: Register 33: Register 34: GPIO Data (GPIODATA), offset 0x000 ............................................................................ 440 GPIO Direction (GPIODIR), offset 0x400 ......................................................................... 441 GPIO Interrupt Sense (GPIOIS), offset 0x404 .................................................................. 442 GPIO Interrupt Both Edges (GPIOIBE), offset 0x408 ........................................................ 443 GPIO Interrupt Event (GPIOIEV), offset 0x40C ................................................................ 444 GPIO Interrupt Mask (GPIOIM), offset 0x410 ................................................................... 445 GPIO Raw Interrupt Status (GPIORIS), offset 0x414 ........................................................ 446 GPIO Masked Interrupt Status (GPIOMIS), offset 0x418 ................................................... 447 GPIO Interrupt Clear (GPIOICR), offset 0x41C ................................................................ 449 GPIO Alternate Function Select (GPIOAFSEL), offset 0x420 ............................................ 450 GPIO 2-mA Drive Select (GPIODR2R), offset 0x500 ........................................................ 452 GPIO 4-mA Drive Select (GPIODR4R), offset 0x504 ........................................................ 453 GPIO 8-mA Drive Select (GPIODR8R), offset 0x508 ........................................................ 454 GPIO Open Drain Select (GPIOODR), offset 0x50C ......................................................... 455 GPIO Pull-Up Select (GPIOPUR), offset 0x510 ................................................................ 456 GPIO Pull-Down Select (GPIOPDR), offset 0x514 ........................................................... 458 GPIO Slew Rate Control Select (GPIOSLR), offset 0x518 ................................................ 460 GPIO Digital Enable (GPIODEN), offset 0x51C ................................................................ 461 GPIO Lock (GPIOLOCK), offset 0x520 ............................................................................ 463 GPIO Commit (GPIOCR), offset 0x524 ............................................................................ 464 GPIO Analog Mode Select (GPIOAMSEL), offset 0x528 ................................................... 466 GPIO Port Control (GPIOPCTL), offset 0x52C ................................................................. 468 GPIO Peripheral Identification 4 (GPIOPeriphID4), offset 0xFD0 ....................................... 470 GPIO Peripheral Identification 5 (GPIOPeriphID5), offset 0xFD4 ....................................... 471 GPIO Peripheral Identification 6 (GPIOPeriphID6), offset 0xFD8 ....................................... 472 GPIO Peripheral Identification 7 (GPIOPeriphID7), offset 0xFDC ...................................... 473 GPIO Peripheral Identification 0 (GPIOPeriphID0), offset 0xFE0 ....................................... 474 GPIO Peripheral Identification 1 (GPIOPeriphID1), offset 0xFE4 ....................................... 475 GPIO Peripheral Identification 2 (GPIOPeriphID2), offset 0xFE8 ....................................... 476 GPIO Peripheral Identification 3 (GPIOPeriphID3), offset 0xFEC ...................................... 477 GPIO PrimeCell Identification 0 (GPIOPCellID0), offset 0xFF0 .......................................... 478 GPIO PrimeCell Identification 1 (GPIOPCellID1), offset 0xFF4 .......................................... 479 GPIO PrimeCell Identification 2 (GPIOPCellID2), offset 0xFF8 .......................................... 480 GPIO PrimeCell Identification 3 (GPIOPCellID3), offset 0xFFC ......................................... 481 External Peripheral Interface (EPI) ............................................................................................. 482 Register 1: Register 2: Register 3: Register 4: Register 5: Register 6: Register 7: EPI Configuration (EPICFG), offset 0x000 ....................................................................... EPI Main Baud Rate (EPIBAUD), offset 0x004 ................................................................. EPI SDRAM Configuration (EPISDRAMCFG), offset 0x010 .............................................. EPI Host-Bus 8 Configuration (EPIHB8CFG), offset 0x010 ............................................... EPI Host-Bus 16 Configuration (EPIHB16CFG), offset 0x010 ........................................... EPI General-Purpose Configuration (EPIGPCFG), offset 0x010 ........................................ EPI Host-Bus 8 Configuration 2 (EPIHB8CFG2), offset 0x014 .......................................... July 03, 2014 514 515 517 519 522 526 531 25 Texas Instruments-Production Data Table of Contents Register 8: Register 9: Register 10: Register 11: Register 12: Register 13: Register 14: Register 15: Register 16: Register 17: Register 18: Register 19: Register 20: Register 21: Register 22: Register 23: Register 24: Register 25: Register 26: Register 27: Register 28: Register 29: Register 30: Register 31: Register 32: EPI Host-Bus 16 Configuration 2 (EPIHB16CFG2), offset 0x014 ....................................... 534 EPI General-Purpose Configuration 2 (EPIGPCFG2), offset 0x014 ................................... 537 EPI Address Map (EPIADDRMAP), offset 0x01C ............................................................. 538 EPI Read Size 0 (EPIRSIZE0), offset 0x020 .................................................................... 540 EPI Read Size 1 (EPIRSIZE1), offset 0x030 .................................................................... 540 EPI Read Address 0 (EPIRADDR0), offset 0x024 ............................................................ 541 EPI Read Address 1 (EPIRADDR1), offset 0x034 ............................................................ 541 EPI Non-Blocking Read Data 0 (EPIRPSTD0), offset 0x028 ............................................. 542 EPI Non-Blocking Read Data 1 (EPIRPSTD1), offset 0x038 ............................................. 542 EPI Status (EPISTAT), offset 0x060 ................................................................................ 544 EPI Read FIFO Count (EPIRFIFOCNT), offset 0x06C ...................................................... 546 EPI Read FIFO (EPIREADFIFO), offset 0x070 ................................................................ 547 EPI Read FIFO Alias 1 (EPIREADFIFO1), offset 0x074 .................................................... 547 EPI Read FIFO Alias 2 (EPIREADFIFO2), offset 0x078 .................................................... 547 EPI Read FIFO Alias 3 (EPIREADFIFO3), offset 0x07C ................................................... 547 EPI Read FIFO Alias 4 (EPIREADFIFO4), offset 0x080 .................................................... 547 EPI Read FIFO Alias 5 (EPIREADFIFO5), offset 0x084 .................................................... 547 EPI Read FIFO Alias 6 (EPIREADFIFO6), offset 0x088 .................................................... 547 EPI Read FIFO Alias 7 (EPIREADFIFO7), offset 0x08C ................................................... 547 EPI FIFO Level Selects (EPIFIFOLVL), offset 0x200 ........................................................ 548 EPI Write FIFO Count (EPIWFIFOCNT), offset 0x204 ...................................................... 550 EPI Interrupt Mask (EPIIM), offset 0x210 ......................................................................... 551 EPI Raw Interrupt Status (EPIRIS), offset 0x214 .............................................................. 552 EPI Masked Interrupt Status (EPIMIS), offset 0x218 ........................................................ 554 EPI Error and Interrupt Status and Clear (EPIEISC), offset 0x21C .................................... 555 General-Purpose Timers ............................................................................................................. 557 Register 1: Register 2: Register 3: Register 4: Register 5: Register 6: Register 7: Register 8: Register 9: Register 10: Register 11: Register 12: Register 13: Register 14: Register 15: Register 16: Register 17: Register 18: Register 19: Register 20: GPTM Configuration (GPTMCFG), offset 0x000 .............................................................. 574 GPTM Timer A Mode (GPTMTAMR), offset 0x004 ........................................................... 575 GPTM Timer B Mode (GPTMTBMR), offset 0x008 ........................................................... 577 GPTM Control (GPTMCTL), offset 0x00C ........................................................................ 579 GPTM Interrupt Mask (GPTMIMR), offset 0x018 .............................................................. 582 GPTM Raw Interrupt Status (GPTMRIS), offset 0x01C ..................................................... 584 GPTM Masked Interrupt Status (GPTMMIS), offset 0x020 ................................................ 587 GPTM Interrupt Clear (GPTMICR), offset 0x024 .............................................................. 590 GPTM Timer A Interval Load (GPTMTAILR), offset 0x028 ................................................ 592 GPTM Timer B Interval Load (GPTMTBILR), offset 0x02C ................................................ 593 GPTM Timer A Match (GPTMTAMATCHR), offset 0x030 .................................................. 594 GPTM Timer B Match (GPTMTBMATCHR), offset 0x034 ................................................. 595 GPTM Timer A Prescale (GPTMTAPR), offset 0x038 ....................................................... 596 GPTM Timer B Prescale (GPTMTBPR), offset 0x03C ...................................................... 597 GPTM TimerA Prescale Match (GPTMTAPMR), offset 0x040 ........................................... 598 GPTM TimerB Prescale Match (GPTMTBPMR), offset 0x044 ........................................... 599 GPTM Timer A (GPTMTAR), offset 0x048 ....................................................................... 600 GPTM Timer B (GPTMTBR), offset 0x04C ....................................................................... 601 GPTM Timer A Value (GPTMTAV), offset 0x050 ............................................................... 602 GPTM Timer B Value (GPTMTBV), offset 0x054 .............................................................. 603 Watchdog Timers ......................................................................................................................... 604 Register 1: Watchdog Load (WDTLOAD), offset 0x000 ...................................................................... 608 26 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 2: Register 3: Register 4: Register 5: Register 6: Register 7: Register 8: Register 9: Register 10: Register 11: Register 12: Register 13: Register 14: Register 15: Register 16: Register 17: Register 18: Register 19: Register 20: Watchdog Value (WDTVALUE), offset 0x004 ................................................................... 609 Watchdog Control (WDTCTL), offset 0x008 ..................................................................... 610 Watchdog Interrupt Clear (WDTICR), offset 0x00C .......................................................... 612 Watchdog Raw Interrupt Status (WDTRIS), offset 0x010 .................................................. 613 Watchdog Masked Interrupt Status (WDTMIS), offset 0x014 ............................................. 614 Watchdog Test (WDTTEST), offset 0x418 ....................................................................... 615 Watchdog Lock (WDTLOCK), offset 0xC00 ..................................................................... 616 Watchdog Peripheral Identification 4 (WDTPeriphID4), offset 0xFD0 ................................. 617 Watchdog Peripheral Identification 5 (WDTPeriphID5), offset 0xFD4 ................................. 618 Watchdog Peripheral Identification 6 (WDTPeriphID6), offset 0xFD8 ................................. 619 Watchdog Peripheral Identification 7 (WDTPeriphID7), offset 0xFDC ................................ 620 Watchdog Peripheral Identification 0 (WDTPeriphID0), offset 0xFE0 ................................. 621 Watchdog Peripheral Identification 1 (WDTPeriphID1), offset 0xFE4 ................................. 622 Watchdog Peripheral Identification 2 (WDTPeriphID2), offset 0xFE8 ................................. 623 Watchdog Peripheral Identification 3 (WDTPeriphID3), offset 0xFEC ................................. 624 Watchdog PrimeCell Identification 0 (WDTPCellID0), offset 0xFF0 .................................... 625 Watchdog PrimeCell Identification 1 (WDTPCellID1), offset 0xFF4 .................................... 626 Watchdog PrimeCell Identification 2 (WDTPCellID2), offset 0xFF8 .................................... 627 Watchdog PrimeCell Identification 3 (WDTPCellID3 ), offset 0xFFC .................................. 628 Analog-to-Digital Converter (ADC) ............................................................................................. 629 Register 1: Register 2: Register 3: Register 4: Register 5: Register 6: Register 7: Register 8: Register 9: Register 10: Register 11: Register 12: Register 13: Register 14: Register 15: Register 16: Register 17: Register 18: Register 19: Register 20: Register 21: Register 22: Register 23: Register 24: Register 25: Register 26: Register 27: Register 28: ADC Active Sample Sequencer (ADCACTSS), offset 0x000 ............................................. 652 ADC Raw Interrupt Status (ADCRIS), offset 0x004 ........................................................... 653 ADC Interrupt Mask (ADCIM), offset 0x008 ..................................................................... 655 ADC Interrupt Status and Clear (ADCISC), offset 0x00C .................................................. 657 ADC Overflow Status (ADCOSTAT), offset 0x010 ............................................................ 660 ADC Event Multiplexer Select (ADCEMUX), offset 0x014 ................................................. 662 ADC Underflow Status (ADCUSTAT), offset 0x018 ........................................................... 667 ADC Sample Sequencer Priority (ADCSSPRI), offset 0x020 ............................................. 668 ADC Sample Phase Control (ADCSPC), offset 0x024 ...................................................... 670 ADC Processor Sample Sequence Initiate (ADCPSSI), offset 0x028 ................................. 672 ADC Sample Averaging Control (ADCSAC), offset 0x030 ................................................. 674 ADC Digital Comparator Interrupt Status and Clear (ADCDCISC), offset 0x034 ................. 675 ADC Control (ADCCTL), offset 0x038 ............................................................................. 677 ADC Sample Sequence Input Multiplexer Select 0 (ADCSSMUX0), offset 0x040 ............... 678 ADC Sample Sequence Control 0 (ADCSSCTL0), offset 0x044 ........................................ 680 ADC Sample Sequence Result FIFO 0 (ADCSSFIFO0), offset 0x048 ................................ 683 ADC Sample Sequence Result FIFO 1 (ADCSSFIFO1), offset 0x068 ................................ 683 ADC Sample Sequence Result FIFO 2 (ADCSSFIFO2), offset 0x088 ................................ 683 ADC Sample Sequence Result FIFO 3 (ADCSSFIFO3), offset 0x0A8 ............................... 683 ADC Sample Sequence FIFO 0 Status (ADCSSFSTAT0), offset 0x04C ............................. 684 ADC Sample Sequence FIFO 1 Status (ADCSSFSTAT1), offset 0x06C ............................. 684 ADC Sample Sequence FIFO 2 Status (ADCSSFSTAT2), offset 0x08C ............................ 684 ADC Sample Sequence FIFO 3 Status (ADCSSFSTAT3), offset 0x0AC ............................ 684 ADC Sample Sequence 0 Operation (ADCSSOP0), offset 0x050 ...................................... 686 ADC Sample Sequence 0 Digital Comparator Select (ADCSSDC0), offset 0x054 .............. 688 ADC Sample Sequence Input Multiplexer Select 1 (ADCSSMUX1), offset 0x060 ............... 690 ADC Sample Sequence Input Multiplexer Select 2 (ADCSSMUX2), offset 0x080 ............... 690 ADC Sample Sequence Control 1 (ADCSSCTL1), offset 0x064 ........................................ 691 July 03, 2014 27 Texas Instruments-Production Data Table of Contents Register 29: Register 30: Register 31: Register 32: Register 33: Register 34: Register 35: Register 36: Register 37: Register 38: Register 39: Register 40: Register 41: Register 42: Register 43: Register 44: Register 45: Register 46: Register 47: Register 48: Register 49: Register 50: Register 51: Register 52: Register 53: Register 54: ADC Sample Sequence Control 2 (ADCSSCTL2), offset 0x084 ........................................ 691 ADC Sample Sequence 1 Operation (ADCSSOP1), offset 0x070 ...................................... 693 ADC Sample Sequence 2 Operation (ADCSSOP2), offset 0x090 ..................................... 693 ADC Sample Sequence 1 Digital Comparator Select (ADCSSDC1), offset 0x074 .............. 694 ADC Sample Sequence 2 Digital Comparator Select (ADCSSDC2), offset 0x094 .............. 694 ADC Sample Sequence Input Multiplexer Select 3 (ADCSSMUX3), offset 0x0A0 ............... 696 ADC Sample Sequence Control 3 (ADCSSCTL3), offset 0x0A4 ........................................ 697 ADC Sample Sequence 3 Operation (ADCSSOP3), offset 0x0B0 ..................................... 698 ADC Sample Sequence 3 Digital Comparator Select (ADCSSDC3), offset 0x0B4 .............. 699 ADC Digital Comparator Reset Initial Conditions (ADCDCRIC), offset 0xD00 ..................... 700 ADC Digital Comparator Control 0 (ADCDCCTL0), offset 0xE00 ....................................... 705 ADC Digital Comparator Control 1 (ADCDCCTL1), offset 0xE04 ....................................... 705 ADC Digital Comparator Control 2 (ADCDCCTL2), offset 0xE08 ....................................... 705 ADC Digital Comparator Control 3 (ADCDCCTL3), offset 0xE0C ...................................... 705 ADC Digital Comparator Control 4 (ADCDCCTL4), offset 0xE10 ....................................... 705 ADC Digital Comparator Control 5 (ADCDCCTL5), offset 0xE14 ....................................... 705 ADC Digital Comparator Control 6 (ADCDCCTL6), offset 0xE18 ....................................... 705 ADC Digital Comparator Control 7 (ADCDCCTL7), offset 0xE1C ...................................... 705 ADC Digital Comparator Range 0 (ADCDCCMP0), offset 0xE40 ....................................... 707 ADC Digital Comparator Range 1 (ADCDCCMP1), offset 0xE44 ....................................... 707 ADC Digital Comparator Range 2 (ADCDCCMP2), offset 0xE48 ....................................... 707 ADC Digital Comparator Range 3 (ADCDCCMP3), offset 0xE4C ...................................... 707 ADC Digital Comparator Range 4 (ADCDCCMP4), offset 0xE50 ....................................... 707 ADC Digital Comparator Range 5 (ADCDCCMP5), offset 0xE54 ....................................... 707 ADC Digital Comparator Range 6 (ADCDCCMP6), offset 0xE58 ....................................... 707 ADC Digital Comparator Range 7 (ADCDCCMP7), offset 0xE5C ...................................... 707 Universal Asynchronous Receivers/Transmitters (UARTs) ..................................................... 709 Register 1: Register 2: Register 3: Register 4: Register 5: Register 6: Register 7: Register 8: Register 9: Register 10: Register 11: Register 12: Register 13: Register 14: Register 15: Register 16: Register 17: Register 18: Register 19: Register 20: Register 21: UART Data (UARTDR), offset 0x000 ............................................................................... 724 UART Receive Status/Error Clear (UARTRSR/UARTECR), offset 0x004 ........................... 726 UART Flag (UARTFR), offset 0x018 ................................................................................ 729 UART IrDA Low-Power Register (UARTILPR), offset 0x020 ............................................. 732 UART Integer Baud-Rate Divisor (UARTIBRD), offset 0x024 ............................................ 733 UART Fractional Baud-Rate Divisor (UARTFBRD), offset 0x028 ....................................... 734 UART Line Control (UARTLCRH), offset 0x02C ............................................................... 735 UART Control (UARTCTL), offset 0x030 ......................................................................... 737 UART Interrupt FIFO Level Select (UARTIFLS), offset 0x034 ........................................... 741 UART Interrupt Mask (UARTIM), offset 0x038 ................................................................. 743 UART Raw Interrupt Status (UARTRIS), offset 0x03C ...................................................... 747 UART Masked Interrupt Status (UARTMIS), offset 0x040 ................................................. 751 UART Interrupt Clear (UARTICR), offset 0x044 ............................................................... 755 UART DMA Control (UARTDMACTL), offset 0x048 .......................................................... 757 UART LIN Control (UARTLCTL), offset 0x090 ................................................................. 758 UART LIN Snap Shot (UARTLSS), offset 0x094 ............................................................... 759 UART LIN Timer (UARTLTIM), offset 0x098 ..................................................................... 760 UART Peripheral Identification 4 (UARTPeriphID4), offset 0xFD0 ..................................... 761 UART Peripheral Identification 5 (UARTPeriphID5), offset 0xFD4 ..................................... 762 UART Peripheral Identification 6 (UARTPeriphID6), offset 0xFD8 ..................................... 763 UART Peripheral Identification 7 (UARTPeriphID7), offset 0xFDC ..................................... 764 28 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 22: Register 23: Register 24: Register 25: Register 26: Register 27: Register 28: Register 29: UART Peripheral Identification 0 (UARTPeriphID0), offset 0xFE0 ...................................... UART Peripheral Identification 1 (UARTPeriphID1), offset 0xFE4 ...................................... UART Peripheral Identification 2 (UARTPeriphID2), offset 0xFE8 ...................................... UART Peripheral Identification 3 (UARTPeriphID3), offset 0xFEC ..................................... UART PrimeCell Identification 0 (UARTPCellID0), offset 0xFF0 ........................................ UART PrimeCell Identification 1 (UARTPCellID1), offset 0xFF4 ........................................ UART PrimeCell Identification 2 (UARTPCellID2), offset 0xFF8 ........................................ UART PrimeCell Identification 3 (UARTPCellID3), offset 0xFFC ........................................ 765 766 767 768 769 770 771 772 Synchronous Serial Interface (SSI) ............................................................................................ 773 Register 1: Register 2: Register 3: Register 4: Register 5: Register 6: Register 7: Register 8: Register 9: Register 10: Register 11: Register 12: Register 13: Register 14: Register 15: Register 16: Register 17: Register 18: Register 19: Register 20: Register 21: Register 22: SSI Control 0 (SSICR0), offset 0x000 .............................................................................. 788 SSI Control 1 (SSICR1), offset 0x004 .............................................................................. 790 SSI Data (SSIDR), offset 0x008 ...................................................................................... 792 SSI Status (SSISR), offset 0x00C ................................................................................... 793 SSI Clock Prescale (SSICPSR), offset 0x010 .................................................................. 795 SSI Interrupt Mask (SSIIM), offset 0x014 ......................................................................... 796 SSI Raw Interrupt Status (SSIRIS), offset 0x018 .............................................................. 797 SSI Masked Interrupt Status (SSIMIS), offset 0x01C ........................................................ 799 SSI Interrupt Clear (SSIICR), offset 0x020 ....................................................................... 801 SSI DMA Control (SSIDMACTL), offset 0x024 ................................................................. 802 SSI Peripheral Identification 4 (SSIPeriphID4), offset 0xFD0 ............................................. 803 SSI Peripheral Identification 5 (SSIPeriphID5), offset 0xFD4 ............................................. 804 SSI Peripheral Identification 6 (SSIPeriphID6), offset 0xFD8 ............................................. 805 SSI Peripheral Identification 7 (SSIPeriphID7), offset 0xFDC ............................................ 806 SSI Peripheral Identification 0 (SSIPeriphID0), offset 0xFE0 ............................................. 807 SSI Peripheral Identification 1 (SSIPeriphID1), offset 0xFE4 ............................................. 808 SSI Peripheral Identification 2 (SSIPeriphID2), offset 0xFE8 ............................................. 809 SSI Peripheral Identification 3 (SSIPeriphID3), offset 0xFEC ............................................ 810 SSI PrimeCell Identification 0 (SSIPCellID0), offset 0xFF0 ............................................... 811 SSI PrimeCell Identification 1 (SSIPCellID1), offset 0xFF4 ............................................... 812 SSI PrimeCell Identification 2 (SSIPCellID2), offset 0xFF8 ............................................... 813 SSI PrimeCell Identification 3 (SSIPCellID3), offset 0xFFC ............................................... 814 Inter-Integrated Circuit (I2C) Interface ........................................................................................ 815 Register 1: Register 2: Register 3: Register 4: Register 5: Register 6: Register 7: Register 8: Register 9: Register 10: Register 11: Register 12: Register 13: Register 14: Register 15: I2C Master Slave Address (I2CMSA), offset 0x000 ........................................................... 832 I2C Master Control/Status (I2CMCS), offset 0x004 ........................................................... 833 I2C Master Data (I2CMDR), offset 0x008 ......................................................................... 838 I2C Master Timer Period (I2CMTPR), offset 0x00C ........................................................... 839 I2C Master Interrupt Mask (I2CMIMR), offset 0x010 ......................................................... 840 I2C Master Raw Interrupt Status (I2CMRIS), offset 0x014 ................................................. 841 I2C Master Masked Interrupt Status (I2CMMIS), offset 0x018 ........................................... 842 I2C Master Interrupt Clear (I2CMICR), offset 0x01C ......................................................... 843 I2C Master Configuration (I2CMCR), offset 0x020 ............................................................ 844 I2C Slave Own Address (I2CSOAR), offset 0x800 ............................................................ 845 I2C Slave Control/Status (I2CSCSR), offset 0x804 ........................................................... 846 I2C Slave Data (I2CSDR), offset 0x808 ........................................................................... 848 I2C Slave Interrupt Mask (I2CSIMR), offset 0x80C ........................................................... 849 I2C Slave Raw Interrupt Status (I2CSRIS), offset 0x810 ................................................... 850 I2C Slave Masked Interrupt Status (I2CSMIS), offset 0x814 .............................................. 851 July 03, 2014 29 Texas Instruments-Production Data Table of Contents Register 16: I2C Slave Interrupt Clear (I2CSICR), offset 0x818 ............................................................ 852 Inter-Integrated Circuit Sound (I2S) Interface ............................................................................ 853 Register 1: Register 2: Register 3: Register 4: Register 5: Register 6: Register 7: Register 8: Register 9: Register 10: Register 11: Register 12: Register 13: Register 14: Register 15: Register 16: Register 17: I2S Transmit FIFO Data (I2STXFIFO), offset 0x000 .......................................................... 866 I2S Transmit FIFO Configuration (I2STXFIFOCFG), offset 0x004 ...................................... 867 I2S Transmit Module Configuration (I2STXCFG), offset 0x008 .......................................... 868 I2S Transmit FIFO Limit (I2STXLIMIT), offset 0x00C ........................................................ 870 I2S Transmit Interrupt Status and Mask (I2STXISM), offset 0x010 ..................................... 871 I2S Transmit FIFO Level (I2STXLEV), offset 0x018 .......................................................... 872 I2S Receive FIFO Data (I2SRXFIFO), offset 0x800 .......................................................... 873 I2S Receive FIFO Configuration (I2SRXFIFOCFG), offset 0x804 ...................................... 874 I2S Receive Module Configuration (I2SRXCFG), offset 0x808 ........................................... 875 I2S Receive FIFO Limit (I2SRXLIMIT), offset 0x80C ......................................................... 878 I2S Receive Interrupt Status and Mask (I2SRXISM), offset 0x810 ..................................... 879 I2S Receive FIFO Level (I2SRXLEV), offset 0x818 ........................................................... 880 I2S Module Configuration (I2SCFG), offset 0xC00 ............................................................ 881 I2S Interrupt Mask (I2SIM), offset 0xC10 ......................................................................... 883 I2S Raw Interrupt Status (I2SRIS), offset 0xC14 ............................................................... 885 I2S Masked Interrupt Status (I2SMIS), offset 0xC18 ......................................................... 887 I2S Interrupt Clear (I2SIC), offset 0xC1C ......................................................................... 889 Controller Area Network (CAN) Module ..................................................................................... 890 Register 1: Register 2: Register 3: Register 4: Register 5: Register 6: Register 7: Register 8: Register 9: Register 10: Register 11: Register 12: Register 13: Register 14: Register 15: Register 16: Register 17: Register 18: Register 19: Register 20: Register 21: Register 22: Register 23: Register 24: Register 25: Register 26: Register 27: CAN Control (CANCTL), offset 0x000 ............................................................................. 912 CAN Status (CANSTS), offset 0x004 ............................................................................... 914 CAN Error Counter (CANERR), offset 0x008 ................................................................... 917 CAN Bit Timing (CANBIT), offset 0x00C .......................................................................... 918 CAN Interrupt (CANINT), offset 0x010 ............................................................................. 919 CAN Test (CANTST), offset 0x014 .................................................................................. 920 CAN Baud Rate Prescaler Extension (CANBRPE), offset 0x018 ....................................... 922 CAN IF1 Command Request (CANIF1CRQ), offset 0x020 ................................................ 923 CAN IF2 Command Request (CANIF2CRQ), offset 0x080 ................................................ 923 CAN IF1 Command Mask (CANIF1CMSK), offset 0x024 .................................................. 924 CAN IF2 Command Mask (CANIF2CMSK), offset 0x084 .................................................. 924 CAN IF1 Mask 1 (CANIF1MSK1), offset 0x028 ................................................................ 927 CAN IF2 Mask 1 (CANIF2MSK1), offset 0x088 ................................................................ 927 CAN IF1 Mask 2 (CANIF1MSK2), offset 0x02C ................................................................ 928 CAN IF2 Mask 2 (CANIF2MSK2), offset 0x08C ................................................................ 928 CAN IF1 Arbitration 1 (CANIF1ARB1), offset 0x030 ......................................................... 930 CAN IF2 Arbitration 1 (CANIF2ARB1), offset 0x090 ......................................................... 930 CAN IF1 Arbitration 2 (CANIF1ARB2), offset 0x034 ......................................................... 931 CAN IF2 Arbitration 2 (CANIF2ARB2), offset 0x094 ......................................................... 931 CAN IF1 Message Control (CANIF1MCTL), offset 0x038 .................................................. 933 CAN IF2 Message Control (CANIF2MCTL), offset 0x098 .................................................. 933 CAN IF1 Data A1 (CANIF1DA1), offset 0x03C ................................................................. 936 CAN IF1 Data A2 (CANIF1DA2), offset 0x040 ................................................................. 936 CAN IF1 Data B1 (CANIF1DB1), offset 0x044 ................................................................. 936 CAN IF1 Data B2 (CANIF1DB2), offset 0x048 ................................................................. 936 CAN IF2 Data A1 (CANIF2DA1), offset 0x09C ................................................................. 936 CAN IF2 Data A2 (CANIF2DA2), offset 0x0A0 ................................................................. 936 30 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 28: Register 29: Register 30: Register 31: Register 32: Register 33: Register 34: Register 35: Register 36: Register 37: CAN IF2 Data B1 (CANIF2DB1), offset 0x0A4 ................................................................. 936 CAN IF2 Data B2 (CANIF2DB2), offset 0x0A8 ................................................................. 936 CAN Transmission Request 1 (CANTXRQ1), offset 0x100 ................................................ 937 CAN Transmission Request 2 (CANTXRQ2), offset 0x104 ................................................ 937 CAN New Data 1 (CANNWDA1), offset 0x120 ................................................................. 938 CAN New Data 2 (CANNWDA2), offset 0x124 ................................................................. 938 CAN Message 1 Interrupt Pending (CANMSG1INT), offset 0x140 ..................................... 939 CAN Message 2 Interrupt Pending (CANMSG2INT), offset 0x144 ..................................... 939 CAN Message 1 Valid (CANMSG1VAL), offset 0x160 ....................................................... 940 CAN Message 2 Valid (CANMSG2VAL), offset 0x164 ....................................................... 940 Ethernet Controller ...................................................................................................................... 941 Register 1: Register 2: Register 3: Register 4: Register 5: Register 6: Register 7: Register 8: Register 9: Register 10: Register 11: Register 12: Register 13: Register 14: Register 15: Register 16: Register 17: Register 18: Register 19: Register 20: Register 21: Register 22: Register 23: Register 24: Register 25: Register 26: Register 27: Register 28: Register 29: Ethernet MAC Raw Interrupt Status/Acknowledge (MACRIS/MACIACK), offset 0x000 ....... 955 Ethernet MAC Interrupt Mask (MACIM), offset 0x004 ....................................................... 958 Ethernet MAC Receive Control (MACRCTL), offset 0x008 ................................................ 960 Ethernet MAC Transmit Control (MACTCTL), offset 0x00C ............................................... 962 Ethernet MAC Data (MACDATA), offset 0x010 ................................................................. 964 Ethernet MAC Individual Address 0 (MACIA0), offset 0x014 ............................................. 966 Ethernet MAC Individual Address 1 (MACIA1), offset 0x018 ............................................. 967 Ethernet MAC Threshold (MACTHR), offset 0x01C .......................................................... 968 Ethernet MAC Management Control (MACMCTL), offset 0x020 ........................................ 970 Ethernet MAC Management Divider (MACMDV), offset 0x024 .......................................... 972 Ethernet MAC Management Transmit Data (MACMTXD), offset 0x02C ............................. 973 Ethernet MAC Management Receive Data (MACMRXD), offset 0x030 .............................. 974 Ethernet MAC Number of Packets (MACNP), offset 0x034 ............................................... 975 Ethernet MAC Transmission Request (MACTR), offset 0x038 ........................................... 976 Ethernet MAC LED Encoding (MACLED), offset 0x040 .................................................... 977 Ethernet PHY MDIX (MDIX), offset 0x044 ....................................................................... 979 Ethernet PHY Management Register 0 – Control (MR0), address 0x00 ............................. 980 Ethernet PHY Management Register 1 – Status (MR1), address 0x01 .............................. 982 Ethernet PHY Management Register 2 – PHY Identifier 1 (MR2), address 0x02 ................. 984 Ethernet PHY Management Register 3 – PHY Identifier 2 (MR3), address 0x03 ................. 985 Ethernet PHY Management Register 4 – Auto-Negotiation Advertisement (MR4), address 0x04 ............................................................................................................................. 986 Ethernet PHY Management Register 5 – Auto-Negotiation Link Partner Base Page Ability (MR5), address 0x05 ..................................................................................................... 988 Ethernet PHY Management Register 6 – Auto-Negotiation Expansion (MR6), address 0x06 ............................................................................................................................. 990 Ethernet PHY Management Register 16 – Vendor-Specific (MR16), address 0x10 ............. 991 Ethernet PHY Management Register 17 – Mode Control/Status (MR17), address 0x11 ...... 992 Ethernet PHY Management Register 27 – Special Control/Status (MR27), address 0x1B ............................................................................................................................. 994 Ethernet PHY Management Register 29 – Interrupt Status (MR29), address 0x1D ............. 995 Ethernet PHY Management Register 30 – Interrupt Mask (MR30), address 0x1E ............... 997 Ethernet PHY Management Register 31 – PHY Special Control/Status (MR31), address 0x1F ............................................................................................................................. 999 Universal Serial Bus (USB) Controller ..................................................................................... 1000 Register 1: Register 2: USB Device Functional Address (USBFADDR), offset 0x000 .......................................... 1028 USB Power (USBPOWER), offset 0x001 ....................................................................... 1029 July 03, 2014 31 Texas Instruments-Production Data Table of Contents Register 3: Register 4: Register 5: Register 6: Register 7: Register 8: Register 9: Register 10: Register 11: Register 12: Register 13: Register 14: Register 15: Register 16: Register 17: Register 18: Register 19: Register 20: Register 21: Register 22: Register 23: Register 24: Register 25: Register 26: Register 27: Register 28: Register 29: Register 30: Register 31: Register 32: Register 33: Register 34: Register 35: Register 36: Register 37: Register 38: Register 39: Register 40: Register 41: Register 42: Register 43: Register 44: Register 45: Register 46: Register 47: Register 48: Register 49: Register 50: USB Transmit Interrupt Status (USBTXIS), offset 0x002 ................................................. 1032 USB Receive Interrupt Status (USBRXIS), offset 0x004 ................................................. 1034 USB Transmit Interrupt Enable (USBTXIE), offset 0x006 ................................................ 1036 USB Receive Interrupt Enable (USBRXIE), offset 0x008 ................................................. 1038 USB General Interrupt Status (USBIS), offset 0x00A ...................................................... 1040 USB Interrupt Enable (USBIE), offset 0x00B .................................................................. 1043 USB Frame Value (USBFRAME), offset 0x00C .............................................................. 1046 USB Endpoint Index (USBEPIDX), offset 0x00E ............................................................ 1047 USB Test Mode (USBTEST), offset 0x00F ..................................................................... 1048 USB FIFO Endpoint 0 (USBFIFO0), offset 0x020 ........................................................... 1050 USB FIFO Endpoint 1 (USBFIFO1), offset 0x024 ........................................................... 1050 USB FIFO Endpoint 2 (USBFIFO2), offset 0x028 ........................................................... 1050 USB FIFO Endpoint 3 (USBFIFO3), offset 0x02C ........................................................... 1050 USB FIFO Endpoint 4 (USBFIFO4), offset 0x030 ........................................................... 1050 USB FIFO Endpoint 5 (USBFIFO5), offset 0x034 ........................................................... 1050 USB FIFO Endpoint 6 (USBFIFO6), offset 0x038 ........................................................... 1050 USB FIFO Endpoint 7 (USBFIFO7), offset 0x03C ........................................................... 1050 USB FIFO Endpoint 8 (USBFIFO8), offset 0x040 ........................................................... 1050 USB FIFO Endpoint 9 (USBFIFO9), offset 0x044 ........................................................... 1050 USB FIFO Endpoint 10 (USBFIFO10), offset 0x048 ....................................................... 1050 USB FIFO Endpoint 11 (USBFIFO11), offset 0x04C ....................................................... 1050 USB FIFO Endpoint 12 (USBFIFO12), offset 0x050 ....................................................... 1050 USB FIFO Endpoint 13 (USBFIFO13), offset 0x054 ....................................................... 1050 USB FIFO Endpoint 14 (USBFIFO14), offset 0x058 ....................................................... 1050 USB FIFO Endpoint 15 (USBFIFO15), offset 0x05C ....................................................... 1050 USB Device Control (USBDEVCTL), offset 0x060 .......................................................... 1052 USB Transmit Dynamic FIFO Sizing (USBTXFIFOSZ), offset 0x062 ................................ 1054 USB Receive Dynamic FIFO Sizing (USBRXFIFOSZ), offset 0x063 ................................ 1054 USB Transmit FIFO Start Address (USBTXFIFOADD), offset 0x064 ................................ 1055 USB Receive FIFO Start Address (USBRXFIFOADD), offset 0x066 ................................ 1055 USB Connect Timing (USBCONTIM), offset 0x07A ........................................................ 1056 USB OTG VBUS Pulse Timing (USBVPLEN), offset 0x07B ............................................ 1057 USB Full-Speed Last Transaction to End of Frame Timing (USBFSEOF), offset 0x07D .... 1058 USB Low-Speed Last Transaction to End of Frame Timing (USBLSEOF), offset 0x07E .... 1059 USB Transmit Functional Address Endpoint 0 (USBTXFUNCADDR0), offset 0x080 ......... 1060 USB Transmit Functional Address Endpoint 1 (USBTXFUNCADDR1), offset 0x088 ......... 1060 USB Transmit Functional Address Endpoint 2 (USBTXFUNCADDR2), offset 0x090 ......... 1060 USB Transmit Functional Address Endpoint 3 (USBTXFUNCADDR3), offset 0x098 ......... 1060 USB Transmit Functional Address Endpoint 4 (USBTXFUNCADDR4), offset 0x0A0 ......... 1060 USB Transmit Functional Address Endpoint 5 (USBTXFUNCADDR5), offset 0x0A8 ......... 1060 USB Transmit Functional Address Endpoint 6 (USBTXFUNCADDR6), offset 0x0B0 ......... 1060 USB Transmit Functional Address Endpoint 7 (USBTXFUNCADDR7), offset 0x0B8 ......... 1060 USB Transmit Functional Address Endpoint 8 (USBTXFUNCADDR8), offset 0x0C0 ........ 1060 USB Transmit Functional Address Endpoint 9 (USBTXFUNCADDR9), offset 0x0C8 ........ 1060 USB Transmit Functional Address Endpoint 10 (USBTXFUNCADDR10), offset 0x0D0 ..... 1060 USB Transmit Functional Address Endpoint 11 (USBTXFUNCADDR11), offset 0x0D8 ..... 1060 USB Transmit Functional Address Endpoint 12 (USBTXFUNCADDR12), offset 0x0E0 ..... 1060 USB Transmit Functional Address Endpoint 13 (USBTXFUNCADDR13), offset 0x0E8 ..... 1060 32 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 51: Register 52: Register 53: Register 54: Register 55: Register 56: Register 57: Register 58: Register 59: Register 60: Register 61: Register 62: Register 63: Register 64: Register 65: Register 66: Register 67: Register 68: Register 69: Register 70: Register 71: Register 72: Register 73: Register 74: Register 75: Register 76: Register 77: Register 78: Register 79: Register 80: Register 81: Register 82: Register 83: Register 84: Register 85: Register 86: Register 87: Register 88: Register 89: Register 90: Register 91: Register 92: Register 93: Register 94: Register 95: Register 96: Register 97: Register 98: USB Transmit Functional Address Endpoint 14 (USBTXFUNCADDR14), offset 0x0F0 ..... 1060 USB Transmit Functional Address Endpoint 15 (USBTXFUNCADDR15), offset 0x0F8 ..... 1060 USB Transmit Hub Address Endpoint 0 (USBTXHUBADDR0), offset 0x082 ..................... 1062 USB Transmit Hub Address Endpoint 1 (USBTXHUBADDR1), offset 0x08A .................... 1062 USB Transmit Hub Address Endpoint 2 (USBTXHUBADDR2), offset 0x092 ..................... 1062 USB Transmit Hub Address Endpoint 3 (USBTXHUBADDR3), offset 0x09A .................... 1062 USB Transmit Hub Address Endpoint 4 (USBTXHUBADDR4), offset 0x0A2 .................... 1062 USB Transmit Hub Address Endpoint 5 (USBTXHUBADDR5), offset 0x0AA .................... 1062 USB Transmit Hub Address Endpoint 6 (USBTXHUBADDR6), offset 0x0B2 .................... 1062 USB Transmit Hub Address Endpoint 7 (USBTXHUBADDR7), offset 0x0BA .................... 1062 USB Transmit Hub Address Endpoint 8 (USBTXHUBADDR8), offset 0x0C2 .................... 1062 USB Transmit Hub Address Endpoint 9 (USBTXHUBADDR9), offset 0x0CA .................... 1062 USB Transmit Hub Address Endpoint 10 (USBTXHUBADDR10), offset 0x0D2 ................ 1062 USB Transmit Hub Address Endpoint 11 (USBTXHUBADDR11), offset 0x0DA ................ 1062 USB Transmit Hub Address Endpoint 12 (USBTXHUBADDR12), offset 0x0E2 ................ 1062 USB Transmit Hub Address Endpoint 13 (USBTXHUBADDR13), offset 0x0EA ................ 1062 USB Transmit Hub Address Endpoint 14 (USBTXHUBADDR14), offset 0x0F2 ................. 1062 USB Transmit Hub Address Endpoint 15 (USBTXHUBADDR15), offset 0x0FA ................ 1062 USB Transmit Hub Port Endpoint 0 (USBTXHUBPORT0), offset 0x083 ........................... 1064 USB Transmit Hub Port Endpoint 1 (USBTXHUBPORT1), offset 0x08B ........................... 1064 USB Transmit Hub Port Endpoint 2 (USBTXHUBPORT2), offset 0x093 ........................... 1064 USB Transmit Hub Port Endpoint 3 (USBTXHUBPORT3), offset 0x09B ........................... 1064 USB Transmit Hub Port Endpoint 4 (USBTXHUBPORT4), offset 0x0A3 ........................... 1064 USB Transmit Hub Port Endpoint 5 (USBTXHUBPORT5), offset 0x0AB .......................... 1064 USB Transmit Hub Port Endpoint 6 (USBTXHUBPORT6), offset 0x0B3 ........................... 1064 USB Transmit Hub Port Endpoint 7 (USBTXHUBPORT7), offset 0x0BB .......................... 1064 USB Transmit Hub Port Endpoint 8 (USBTXHUBPORT8), offset 0x0C3 .......................... 1064 USB Transmit Hub Port Endpoint 9 (USBTXHUBPORT9), offset 0x0CB .......................... 1064 USB Transmit Hub Port Endpoint 10 (USBTXHUBPORT10), offset 0x0D3 ....................... 1064 USB Transmit Hub Port Endpoint 11 (USBTXHUBPORT11), offset 0x0DB ....................... 1064 USB Transmit Hub Port Endpoint 12 (USBTXHUBPORT12), offset 0x0E3 ....................... 1064 USB Transmit Hub Port Endpoint 13 (USBTXHUBPORT13), offset 0x0EB ...................... 1064 USB Transmit Hub Port Endpoint 14 (USBTXHUBPORT14), offset 0x0F3 ....................... 1064 USB Transmit Hub Port Endpoint 15 (USBTXHUBPORT15), offset 0x0FB ....................... 1064 USB Receive Functional Address Endpoint 1 (USBRXFUNCADDR1), offset 0x08C ......... 1066 USB Receive Functional Address Endpoint 2 (USBRXFUNCADDR2), offset 0x094 ......... 1066 USB Receive Functional Address Endpoint 3 (USBRXFUNCADDR3), offset 0x09C ......... 1066 USB Receive Functional Address Endpoint 4 (USBRXFUNCADDR4), offset 0x0A4 ......... 1066 USB Receive Functional Address Endpoint 5 (USBRXFUNCADDR5), offset 0x0AC ......... 1066 USB Receive Functional Address Endpoint 6 (USBRXFUNCADDR6), offset 0x0B4 ......... 1066 USB Receive Functional Address Endpoint 7 (USBRXFUNCADDR7), offset 0x0BC ......... 1066 USB Receive Functional Address Endpoint 8 (USBRXFUNCADDR8), offset 0x0C4 ......... 1066 USB Receive Functional Address Endpoint 9 (USBRXFUNCADDR9), offset 0x0CC ........ 1066 USB Receive Functional Address Endpoint 10 (USBRXFUNCADDR10), offset 0x0D4 ..... 1066 USB Receive Functional Address Endpoint 11 (USBRXFUNCADDR11), offset 0x0DC ..... 1066 USB Receive Functional Address Endpoint 12 (USBRXFUNCADDR12), offset 0x0E4 ..... 1066 USB Receive Functional Address Endpoint 13 (USBRXFUNCADDR13), offset 0x0EC ..... 1066 USB Receive Functional Address Endpoint 14 (USBRXFUNCADDR14), offset 0x0F4 ...... 1066 July 03, 2014 33 Texas Instruments-Production Data Table of Contents Register 99: Register 100: Register 101: Register 102: Register 103: Register 104: Register 105: Register 106: Register 107: Register 108: Register 109: Register 110: Register 111: Register 112: Register 113: Register 114: Register 115: Register 116: Register 117: Register 118: Register 119: Register 120: Register 121: Register 122: Register 123: Register 124: Register 125: Register 126: Register 127: Register 128: Register 129: Register 130: Register 131: Register 132: Register 133: Register 134: Register 135: Register 136: Register 137: Register 138: Register 139: Register 140: Register 141: Register 142: Register 143: Register 144: Register 145: Register 146: USB Receive Functional Address Endpoint 15 (USBRXFUNCADDR15), offset 0x0FC ..... 1066 USB Receive Hub Address Endpoint 1 (USBRXHUBADDR1), offset 0x08E ..................... 1068 USB Receive Hub Address Endpoint 2 (USBRXHUBADDR2), offset 0x096 ..................... 1068 USB Receive Hub Address Endpoint 3 (USBRXHUBADDR3), offset 0x09E ..................... 1068 USB Receive Hub Address Endpoint 4 (USBRXHUBADDR4), offset 0x0A6 ..................... 1068 USB Receive Hub Address Endpoint 5 (USBRXHUBADDR5), offset 0x0AE .................... 1068 USB Receive Hub Address Endpoint 6 (USBRXHUBADDR6), offset 0x0B6 ..................... 1068 USB Receive Hub Address Endpoint 7 (USBRXHUBADDR7), offset 0x0BE .................... 1068 USB Receive Hub Address Endpoint 8 (USBRXHUBADDR8), offset 0x0C6 .................... 1068 USB Receive Hub Address Endpoint 9 (USBRXHUBADDR9), offset 0x0CE .................... 1068 USB Receive Hub Address Endpoint 10 (USBRXHUBADDR10), offset 0x0D6 ................. 1068 USB Receive Hub Address Endpoint 11 (USBRXHUBADDR11), offset 0x0DE ................. 1068 USB Receive Hub Address Endpoint 12 (USBRXHUBADDR12), offset 0x0E6 ................. 1068 USB Receive Hub Address Endpoint 13 (USBRXHUBADDR13), offset 0x0EE ................ 1068 USB Receive Hub Address Endpoint 14 (USBRXHUBADDR14), offset 0x0F6 ................. 1068 USB Receive Hub Address Endpoint 15 (USBRXHUBADDR15), offset 0x0FE ................. 1068 USB Receive Hub Port Endpoint 1 (USBRXHUBPORT1), offset 0x08F ........................... 1070 USB Receive Hub Port Endpoint 2 (USBRXHUBPORT2), offset 0x097 ........................... 1070 USB Receive Hub Port Endpoint 3 (USBRXHUBPORT3), offset 0x09F ........................... 1070 USB Receive Hub Port Endpoint 4 (USBRXHUBPORT4), offset 0x0A7 ........................... 1070 USB Receive Hub Port Endpoint 5 (USBRXHUBPORT5), offset 0x0AF ........................... 1070 USB Receive Hub Port Endpoint 6 (USBRXHUBPORT6), offset 0x0B7 ........................... 1070 USB Receive Hub Port Endpoint 7 (USBRXHUBPORT7), offset 0x0BF ........................... 1070 USB Receive Hub Port Endpoint 8 (USBRXHUBPORT8), offset 0x0C7 ........................... 1070 USB Receive Hub Port Endpoint 9 (USBRXHUBPORT9), offset 0x0CF ........................... 1070 USB Receive Hub Port Endpoint 10 (USBRXHUBPORT10), offset 0x0D7 ....................... 1070 USB Receive Hub Port Endpoint 11 (USBRXHUBPORT11), offset 0x0DF ....................... 1070 USB Receive Hub Port Endpoint 12 (USBRXHUBPORT12), offset 0x0E7 ....................... 1070 USB Receive Hub Port Endpoint 13 (USBRXHUBPORT13), offset 0x0EF ....................... 1070 USB Receive Hub Port Endpoint 14 (USBRXHUBPORT14), offset 0x0F7 ....................... 1070 USB Receive Hub Port Endpoint 15 (USBRXHUBPORT15), offset 0x0FF ....................... 1070 USB Maximum Transmit Data Endpoint 1 (USBTXMAXP1), offset 0x110 ......................... 1072 USB Maximum Transmit Data Endpoint 2 (USBTXMAXP2), offset 0x120 ........................ 1072 USB Maximum Transmit Data Endpoint 3 (USBTXMAXP3), offset 0x130 ........................ 1072 USB Maximum Transmit Data Endpoint 4 (USBTXMAXP4), offset 0x140 ........................ 1072 USB Maximum Transmit Data Endpoint 5 (USBTXMAXP5), offset 0x150 ........................ 1072 USB Maximum Transmit Data Endpoint 6 (USBTXMAXP6), offset 0x160 ........................ 1072 USB Maximum Transmit Data Endpoint 7 (USBTXMAXP7), offset 0x170 ........................ 1072 USB Maximum Transmit Data Endpoint 8 (USBTXMAXP8), offset 0x180 ........................ 1072 USB Maximum Transmit Data Endpoint 9 (USBTXMAXP9), offset 0x190 ........................ 1072 USB Maximum Transmit Data Endpoint 10 (USBTXMAXP10), offset 0x1A0 .................... 1072 USB Maximum Transmit Data Endpoint 11 (USBTXMAXP11), offset 0x1B0 ..................... 1072 USB Maximum Transmit Data Endpoint 12 (USBTXMAXP12), offset 0x1C0 .................... 1072 USB Maximum Transmit Data Endpoint 13 (USBTXMAXP13), offset 0x1D0 .................... 1072 USB Maximum Transmit Data Endpoint 14 (USBTXMAXP14), offset 0x1E0 .................... 1072 USB Maximum Transmit Data Endpoint 15 (USBTXMAXP15), offset 0x1F0 ..................... 1072 USB Control and Status Endpoint 0 Low (USBCSRL0), offset 0x102 ............................... 1074 USB Control and Status Endpoint 0 High (USBCSRH0), offset 0x103 ............................. 1078 34 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 147: Register 148: Register 149: Register 150: Register 151: Register 152: Register 153: Register 154: Register 155: Register 156: Register 157: Register 158: Register 159: Register 160: Register 161: Register 162: Register 163: Register 164: Register 165: Register 166: Register 167: Register 168: Register 169: Register 170: Register 171: Register 172: Register 173: Register 174: Register 175: Register 176: Register 177: Register 178: Register 179: Register 180: Register 181: Register 182: Register 183: Register 184: Register 185: Register 186: Register 187: Register 188: Register 189: Register 190: Register 191: Register 192: Register 193: Register 194: USB Receive Byte Count Endpoint 0 (USBCOUNT0), offset 0x108 ................................. 1080 USB Type Endpoint 0 (USBTYPE0), offset 0x10A .......................................................... 1081 USB NAK Limit (USBNAKLMT), offset 0x10B ................................................................ 1082 USB Transmit Control and Status Endpoint 1 Low (USBTXCSRL1), offset 0x112 ............. 1083 USB Transmit Control and Status Endpoint 2 Low (USBTXCSRL2), offset 0x122 ............. 1083 USB Transmit Control and Status Endpoint 3 Low (USBTXCSRL3), offset 0x132 ............. 1083 USB Transmit Control and Status Endpoint 4 Low (USBTXCSRL4), offset 0x142 ............. 1083 USB Transmit Control and Status Endpoint 5 Low (USBTXCSRL5), offset 0x152 ............. 1083 USB Transmit Control and Status Endpoint 6 Low (USBTXCSRL6), offset 0x162 ............. 1083 USB Transmit Control and Status Endpoint 7 Low (USBTXCSRL7), offset 0x172 ............. 1083 USB Transmit Control and Status Endpoint 8 Low (USBTXCSRL8), offset 0x182 ............. 1083 USB Transmit Control and Status Endpoint 9 Low (USBTXCSRL9), offset 0x192 ............. 1083 USB Transmit Control and Status Endpoint 10 Low (USBTXCSRL10), offset 0x1A2 ......... 1083 USB Transmit Control and Status Endpoint 11 Low (USBTXCSRL11), offset 0x1B2 ......... 1083 USB Transmit Control and Status Endpoint 12 Low (USBTXCSRL12), offset 0x1C2 ........ 1083 USB Transmit Control and Status Endpoint 13 Low (USBTXCSRL13), offset 0x1D2 ........ 1083 USB Transmit Control and Status Endpoint 14 Low (USBTXCSRL14), offset 0x1E2 ......... 1083 USB Transmit Control and Status Endpoint 15 Low (USBTXCSRL15), offset 0x1F2 ......... 1083 USB Transmit Control and Status Endpoint 1 High (USBTXCSRH1), offset 0x113 ............ 1088 USB Transmit Control and Status Endpoint 2 High (USBTXCSRH2), offset 0x123 ........... 1088 USB Transmit Control and Status Endpoint 3 High (USBTXCSRH3), offset 0x133 ........... 1088 USB Transmit Control and Status Endpoint 4 High (USBTXCSRH4), offset 0x143 ........... 1088 USB Transmit Control and Status Endpoint 5 High (USBTXCSRH5), offset 0x153 ........... 1088 USB Transmit Control and Status Endpoint 6 High (USBTXCSRH6), offset 0x163 ........... 1088 USB Transmit Control and Status Endpoint 7 High (USBTXCSRH7), offset 0x173 ........... 1088 USB Transmit Control and Status Endpoint 8 High (USBTXCSRH8), offset 0x183 ........... 1088 USB Transmit Control and Status Endpoint 9 High (USBTXCSRH9), offset 0x193 ........... 1088 USB Transmit Control and Status Endpoint 10 High (USBTXCSRH10), offset 0x1A3 ....... 1088 USB Transmit Control and Status Endpoint 11 High (USBTXCSRH11), offset 0x1B3 ........ 1088 USB Transmit Control and Status Endpoint 12 High (USBTXCSRH12), offset 0x1C3 ....... 1088 USB Transmit Control and Status Endpoint 13 High (USBTXCSRH13), offset 0x1D3 ....... 1088 USB Transmit Control and Status Endpoint 14 High (USBTXCSRH14), offset 0x1E3 ....... 1088 USB Transmit Control and Status Endpoint 15 High (USBTXCSRH15), offset 0x1F3 ........ 1088 USB Maximum Receive Data Endpoint 1 (USBRXMAXP1), offset 0x114 ......................... 1092 USB Maximum Receive Data Endpoint 2 (USBRXMAXP2), offset 0x124 ......................... 1092 USB Maximum Receive Data Endpoint 3 (USBRXMAXP3), offset 0x134 ......................... 1092 USB Maximum Receive Data Endpoint 4 (USBRXMAXP4), offset 0x144 ......................... 1092 USB Maximum Receive Data Endpoint 5 (USBRXMAXP5), offset 0x154 ......................... 1092 USB Maximum Receive Data Endpoint 6 (USBRXMAXP6), offset 0x164 ......................... 1092 USB Maximum Receive Data Endpoint 7 (USBRXMAXP7), offset 0x174 ......................... 1092 USB Maximum Receive Data Endpoint 8 (USBRXMAXP8), offset 0x184 ......................... 1092 USB Maximum Receive Data Endpoint 9 (USBRXMAXP9), offset 0x194 ......................... 1092 USB Maximum Receive Data Endpoint 10 (USBRXMAXP10), offset 0x1A4 ..................... 1092 USB Maximum Receive Data Endpoint 11 (USBRXMAXP11), offset 0x1B4 ..................... 1092 USB Maximum Receive Data Endpoint 12 (USBRXMAXP12), offset 0x1C4 ..................... 1092 USB Maximum Receive Data Endpoint 13 (USBRXMAXP13), offset 0x1D4 ..................... 1092 USB Maximum Receive Data Endpoint 14 (USBRXMAXP14), offset 0x1E4 ..................... 1092 USB Maximum Receive Data Endpoint 15 (USBRXMAXP15), offset 0x1F4 ..................... 1092 July 03, 2014 35 Texas Instruments-Production Data Table of Contents Register 195: Register 196: Register 197: Register 198: Register 199: Register 200: Register 201: Register 202: Register 203: Register 204: Register 205: Register 206: Register 207: Register 208: Register 209: Register 210: Register 211: Register 212: Register 213: Register 214: Register 215: Register 216: Register 217: Register 218: Register 219: Register 220: Register 221: Register 222: Register 223: Register 224: Register 225: Register 226: Register 227: Register 228: Register 229: Register 230: Register 231: Register 232: Register 233: Register 234: Register 235: Register 236: Register 237: Register 238: Register 239: Register 240: Register 241: Register 242: USB Receive Control and Status Endpoint 1 Low (USBRXCSRL1), offset 0x116 ............. 1094 USB Receive Control and Status Endpoint 2 Low (USBRXCSRL2), offset 0x126 ............. 1094 USB Receive Control and Status Endpoint 3 Low (USBRXCSRL3), offset 0x136 ............. 1094 USB Receive Control and Status Endpoint 4 Low (USBRXCSRL4), offset 0x146 ............. 1094 USB Receive Control and Status Endpoint 5 Low (USBRXCSRL5), offset 0x156 ............. 1094 USB Receive Control and Status Endpoint 6 Low (USBRXCSRL6), offset 0x166 ............. 1094 USB Receive Control and Status Endpoint 7 Low (USBRXCSRL7), offset 0x176 ............. 1094 USB Receive Control and Status Endpoint 8 Low (USBRXCSRL8), offset 0x186 ............. 1094 USB Receive Control and Status Endpoint 9 Low (USBRXCSRL9), offset 0x196 ............. 1094 USB Receive Control and Status Endpoint 10 Low (USBRXCSRL10), offset 0x1A6 ......... 1094 USB Receive Control and Status Endpoint 11 Low (USBRXCSRL11), offset 0x1B6 .......... 1094 USB Receive Control and Status Endpoint 12 Low (USBRXCSRL12), offset 0x1C6 ......... 1094 USB Receive Control and Status Endpoint 13 Low (USBRXCSRL13), offset 0x1D6 ......... 1094 USB Receive Control and Status Endpoint 14 Low (USBRXCSRL14), offset 0x1E6 ......... 1094 USB Receive Control and Status Endpoint 15 Low (USBRXCSRL15), offset 0x1F6 ......... 1094 USB Receive Control and Status Endpoint 1 High (USBRXCSRH1), offset 0x117 ............ 1099 USB Receive Control and Status Endpoint 2 High (USBRXCSRH2), offset 0x127 ............ 1099 USB Receive Control and Status Endpoint 3 High (USBRXCSRH3), offset 0x137 ............ 1099 USB Receive Control and Status Endpoint 4 High (USBRXCSRH4), offset 0x147 ............ 1099 USB Receive Control and Status Endpoint 5 High (USBRXCSRH5), offset 0x157 ............ 1099 USB Receive Control and Status Endpoint 6 High (USBRXCSRH6), offset 0x167 ............ 1099 USB Receive Control and Status Endpoint 7 High (USBRXCSRH7), offset 0x177 ............ 1099 USB Receive Control and Status Endpoint 8 High (USBRXCSRH8), offset 0x187 ............ 1099 USB Receive Control and Status Endpoint 9 High (USBRXCSRH9), offset 0x197 ............ 1099 USB Receive Control and Status Endpoint 10 High (USBRXCSRH10), offset 0x1A7 ........ 1099 USB Receive Control and Status Endpoint 11 High (USBRXCSRH11), offset 0x1B7 ........ 1099 USB Receive Control and Status Endpoint 12 High (USBRXCSRH12), offset 0x1C7 ........ 1099 USB Receive Control and Status Endpoint 13 High (USBRXCSRH13), offset 0x1D7 ........ 1099 USB Receive Control and Status Endpoint 14 High (USBRXCSRH14), offset 0x1E7 ........ 1099 USB Receive Control and Status Endpoint 15 High (USBRXCSRH15), offset 0x1F7 ........ 1099 USB Receive Byte Count Endpoint 1 (USBRXCOUNT1), offset 0x118 ............................. 1104 USB Receive Byte Count Endpoint 2 (USBRXCOUNT2), offset 0x128 ............................ 1104 USB Receive Byte Count Endpoint 3 (USBRXCOUNT3), offset 0x138 ............................ 1104 USB Receive Byte Count Endpoint 4 (USBRXCOUNT4), offset 0x148 ............................ 1104 USB Receive Byte Count Endpoint 5 (USBRXCOUNT5), offset 0x158 ............................ 1104 USB Receive Byte Count Endpoint 6 (USBRXCOUNT6), offset 0x168 ............................ 1104 USB Receive Byte Count Endpoint 7 (USBRXCOUNT7), offset 0x178 ............................ 1104 USB Receive Byte Count Endpoint 8 (USBRXCOUNT8), offset 0x188 ............................ 1104 USB Receive Byte Count Endpoint 9 (USBRXCOUNT9), offset 0x198 ............................ 1104 USB Receive Byte Count Endpoint 10 (USBRXCOUNT10), offset 0x1A8 ........................ 1104 USB Receive Byte Count Endpoint 11 (USBRXCOUNT11), offset 0x1B8 ......................... 1104 USB Receive Byte Count Endpoint 12 (USBRXCOUNT12), offset 0x1C8 ........................ 1104 USB Receive Byte Count Endpoint 13 (USBRXCOUNT13), offset 0x1D8 ........................ 1104 USB Receive Byte Count Endpoint 14 (USBRXCOUNT14), offset 0x1E8 ........................ 1104 USB Receive Byte Count Endpoint 15 (USBRXCOUNT15), offset 0x1F8 ........................ 1104 USB Host Transmit Configure Type Endpoint 1 (USBTXTYPE1), offset 0x11A ................. 1106 USB Host Transmit Configure Type Endpoint 2 (USBTXTYPE2), offset 0x12A ................. 1106 USB Host Transmit Configure Type Endpoint 3 (USBTXTYPE3), offset 0x13A ................. 1106 36 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 243: Register 244: Register 245: Register 246: Register 247: Register 248: Register 249: Register 250: Register 251: Register 252: Register 253: Register 254: Register 255: Register 256: Register 257: Register 258: Register 259: Register 260: Register 261: Register 262: Register 263: Register 264: Register 265: Register 266: Register 267: Register 268: Register 269: Register 270: Register 271: Register 272: Register 273: Register 274: Register 275: Register 276: Register 277: Register 278: Register 279: Register 280: Register 281: Register 282: Register 283: Register 284: Register 285: Register 286: Register 287: Register 288: Register 289: Register 290: USB Host Transmit Configure Type Endpoint 4 (USBTXTYPE4), offset 0x14A ................. 1106 USB Host Transmit Configure Type Endpoint 5 (USBTXTYPE5), offset 0x15A ................. 1106 USB Host Transmit Configure Type Endpoint 6 (USBTXTYPE6), offset 0x16A ................. 1106 USB Host Transmit Configure Type Endpoint 7 (USBTXTYPE7), offset 0x17A ................. 1106 USB Host Transmit Configure Type Endpoint 8 (USBTXTYPE8), offset 0x18A ................. 1106 USB Host Transmit Configure Type Endpoint 9 (USBTXTYPE9), offset 0x19A ................. 1106 USB Host Transmit Configure Type Endpoint 10 (USBTXTYPE10), offset 0x1AA ............. 1106 USB Host Transmit Configure Type Endpoint 11 (USBTXTYPE11), offset 0x1BA ............. 1106 USB Host Transmit Configure Type Endpoint 12 (USBTXTYPE12), offset 0x1CA ............. 1106 USB Host Transmit Configure Type Endpoint 13 (USBTXTYPE13), offset 0x1DA ............. 1106 USB Host Transmit Configure Type Endpoint 14 (USBTXTYPE14), offset 0x1EA ............. 1106 USB Host Transmit Configure Type Endpoint 15 (USBTXTYPE15), offset 0x1FA ............. 1106 USB Host Transmit Interval Endpoint 1 (USBTXINTERVAL1), offset 0x11B ..................... 1108 USB Host Transmit Interval Endpoint 2 (USBTXINTERVAL2), offset 0x12B ..................... 1108 USB Host Transmit Interval Endpoint 3 (USBTXINTERVAL3), offset 0x13B ..................... 1108 USB Host Transmit Interval Endpoint 4 (USBTXINTERVAL4), offset 0x14B ..................... 1108 USB Host Transmit Interval Endpoint 5 (USBTXINTERVAL5), offset 0x15B ..................... 1108 USB Host Transmit Interval Endpoint 6 (USBTXINTERVAL6), offset 0x16B ..................... 1108 USB Host Transmit Interval Endpoint 7 (USBTXINTERVAL7), offset 0x17B ..................... 1108 USB Host Transmit Interval Endpoint 8 (USBTXINTERVAL8), offset 0x18B ..................... 1108 USB Host Transmit Interval Endpoint 9 (USBTXINTERVAL9), offset 0x19B ..................... 1108 USB Host Transmit Interval Endpoint 10 (USBTXINTERVAL10), offset 0x1AB ................. 1108 USB Host Transmit Interval Endpoint 11 (USBTXINTERVAL11), offset 0x1BB .................. 1108 USB Host Transmit Interval Endpoint 12 (USBTXINTERVAL12), offset 0x1CB ................. 1108 USB Host Transmit Interval Endpoint 13 (USBTXINTERVAL13), offset 0x1DB ................. 1108 USB Host Transmit Interval Endpoint 14 (USBTXINTERVAL14), offset 0x1EB ................. 1108 USB Host Transmit Interval Endpoint 15 (USBTXINTERVAL15), offset 0x1FB ................. 1108 USB Host Configure Receive Type Endpoint 1 (USBRXTYPE1), offset 0x11C ................. 1110 USB Host Configure Receive Type Endpoint 2 (USBRXTYPE2), offset 0x12C ................. 1110 USB Host Configure Receive Type Endpoint 3 (USBRXTYPE3), offset 0x13C ................. 1110 USB Host Configure Receive Type Endpoint 4 (USBRXTYPE4), offset 0x14C ................. 1110 USB Host Configure Receive Type Endpoint 5 (USBRXTYPE5), offset 0x15C ................. 1110 USB Host Configure Receive Type Endpoint 6 (USBRXTYPE6), offset 0x16C ................. 1110 USB Host Configure Receive Type Endpoint 7 (USBRXTYPE7), offset 0x17C ................. 1110 USB Host Configure Receive Type Endpoint 8 (USBRXTYPE8), offset 0x18C ................. 1110 USB Host Configure Receive Type Endpoint 9 (USBRXTYPE9), offset 0x19C ................. 1110 USB Host Configure Receive Type Endpoint 10 (USBRXTYPE10), offset 0x1AC ............. 1110 USB Host Configure Receive Type Endpoint 11 (USBRXTYPE11), offset 0x1BC ............. 1110 USB Host Configure Receive Type Endpoint 12 (USBRXTYPE12), offset 0x1CC ............. 1110 USB Host Configure Receive Type Endpoint 13 (USBRXTYPE13), offset 0x1DC ............. 1110 USB Host Configure Receive Type Endpoint 14 (USBRXTYPE14), offset 0x1EC ............. 1110 USB Host Configure Receive Type Endpoint 15 (USBRXTYPE15), offset 0x1FC ............. 1110 USB Host Receive Polling Interval Endpoint 1 (USBRXINTERVAL1), offset 0x11D ........... 1112 USB Host Receive Polling Interval Endpoint 2 (USBRXINTERVAL2), offset 0x12D ........... 1112 USB Host Receive Polling Interval Endpoint 3 (USBRXINTERVAL3), offset 0x13D ........... 1112 USB Host Receive Polling Interval Endpoint 4 (USBRXINTERVAL4), offset 0x14D ........... 1112 USB Host Receive Polling Interval Endpoint 5 (USBRXINTERVAL5), offset 0x15D ........... 1112 USB Host Receive Polling Interval Endpoint 6 (USBRXINTERVAL6), offset 0x16D ........... 1112 July 03, 2014 37 Texas Instruments-Production Data Table of Contents Register 291: Register 292: Register 293: Register 294: Register 295: Register 296: Register 297: Register 298: Register 299: Register 300: Register 301: Register 302: Register 303: Register 304: Register 305: Register 306: Register 307: Register 308: Register 309: Register 310: Register 311: Register 312: Register 313: Register 314: Register 315: Register 316: Register 317: Register 318: Register 319: Register 320: Register 321: Register 322: Register 323: Register 324: USB Host Receive Polling Interval Endpoint 7 (USBRXINTERVAL7), offset 0x17D ........... 1112 USB Host Receive Polling Interval Endpoint 8 (USBRXINTERVAL8), offset 0x18D ........... 1112 USB Host Receive Polling Interval Endpoint 9 (USBRXINTERVAL9), offset 0x19D ........... 1112 USB Host Receive Polling Interval Endpoint 10 (USBRXINTERVAL10), offset 0x1AD ...... 1112 USB Host Receive Polling Interval Endpoint 11 (USBRXINTERVAL11), offset 0x1BD ....... 1112 USB Host Receive Polling Interval Endpoint 12 (USBRXINTERVAL12), offset 0x1CD ...... 1112 USB Host Receive Polling Interval Endpoint 13 (USBRXINTERVAL13), offset 0x1DD ...... 1112 USB Host Receive Polling Interval Endpoint 14 (USBRXINTERVAL14), offset 0x1ED ...... 1112 USB Host Receive Polling Interval Endpoint 15 (USBRXINTERVAL15), offset 0x1FD ....... 1112 USB Request Packet Count in Block Transfer Endpoint 1 (USBRQPKTCOUNT1), offset 0x304 .......................................................................................................................... 1114 USB Request Packet Count in Block Transfer Endpoint 2 (USBRQPKTCOUNT2), offset 0x308 .......................................................................................................................... 1114 USB Request Packet Count in Block Transfer Endpoint 3 (USBRQPKTCOUNT3), offset 0x30C ......................................................................................................................... 1114 USB Request Packet Count in Block Transfer Endpoint 4 (USBRQPKTCOUNT4), offset 0x310 .......................................................................................................................... 1114 USB Request Packet Count in Block Transfer Endpoint 5 (USBRQPKTCOUNT5), offset 0x314 .......................................................................................................................... 1114 USB Request Packet Count in Block Transfer Endpoint 6 (USBRQPKTCOUNT6), offset 0x318 .......................................................................................................................... 1114 USB Request Packet Count in Block Transfer Endpoint 7 (USBRQPKTCOUNT7), offset 0x31C ......................................................................................................................... 1114 USB Request Packet Count in Block Transfer Endpoint 8 (USBRQPKTCOUNT8), offset 0x320 .......................................................................................................................... 1114 USB Request Packet Count in Block Transfer Endpoint 9 (USBRQPKTCOUNT9), offset 0x324 .......................................................................................................................... 1114 USB Request Packet Count in Block Transfer Endpoint 10 (USBRQPKTCOUNT10), offset 0x328 .......................................................................................................................... 1114 USB Request Packet Count in Block Transfer Endpoint 11 (USBRQPKTCOUNT11), offset 0x32C ......................................................................................................................... 1114 USB Request Packet Count in Block Transfer Endpoint 12 (USBRQPKTCOUNT12), offset 0x330 .......................................................................................................................... 1114 USB Request Packet Count in Block Transfer Endpoint 13 (USBRQPKTCOUNT13), offset 0x334 .......................................................................................................................... 1114 USB Request Packet Count in Block Transfer Endpoint 14 (USBRQPKTCOUNT14), offset 0x338 .......................................................................................................................... 1114 USB Request Packet Count in Block Transfer Endpoint 15 (USBRQPKTCOUNT15), offset 0x33C ......................................................................................................................... 1114 USB Receive Double Packet Buffer Disable (USBRXDPKTBUFDIS), offset 0x340 ........... 1116 USB Transmit Double Packet Buffer Disable (USBTXDPKTBUFDIS), offset 0x342 .......... 1118 USB External Power Control (USBEPC), offset 0x400 .................................................... 1120 USB External Power Control Raw Interrupt Status (USBEPCRIS), offset 0x404 ............... 1123 USB External Power Control Interrupt Mask (USBEPCIM), offset 0x408 .......................... 1124 USB External Power Control Interrupt Status and Clear (USBEPCISC), offset 0x40C ....... 1125 USB Device RESUME Raw Interrupt Status (USBDRRIS), offset 0x410 .......................... 1126 USB Device RESUME Interrupt Mask (USBDRIM), offset 0x414 ..................................... 1127 USB Device RESUME Interrupt Status and Clear (USBDRISC), offset 0x418 .................. 1128 USB General-Purpose Control and Status (USBGPCS), offset 0x41C ............................. 1129 38 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 325: Register 326: Register 327: Register 328: Register 329: Register 330: Register 331: Register 332: USB VBUS Droop Control (USBVDC), offset 0x430 ....................................................... 1130 USB VBUS Droop Control Raw Interrupt Status (USBVDCRIS), offset 0x434 .................. 1131 USB VBUS Droop Control Interrupt Mask (USBVDCIM), offset 0x438 ............................. 1132 USB VBUS Droop Control Interrupt Status and Clear (USBVDCISC), offset 0x43C .......... 1133 USB ID Valid Detect Raw Interrupt Status (USBIDVRIS), offset 0x444 ............................. 1134 USB ID Valid Detect Interrupt Mask (USBIDVIM), offset 0x448 ........................................ 1135 USB ID Valid Detect Interrupt Status and Clear (USBIDVISC), offset 0x44C .................... 1136 USB DMA Select (USBDMASEL), offset 0x450 .............................................................. 1137 Analog Comparators ................................................................................................................. 1139 Register 1: Register 2: Register 3: Register 4: Register 5: Register 6: Register 7: Register 8: Register 9: Register 10: Analog Comparator Masked Interrupt Status (ACMIS), offset 0x000 ................................ 1146 Analog Comparator Raw Interrupt Status (ACRIS), offset 0x004 ..................................... 1147 Analog Comparator Interrupt Enable (ACINTEN), offset 0x008 ....................................... 1148 Analog Comparator Reference Voltage Control (ACREFCTL), offset 0x010 ..................... 1149 Analog Comparator Status 0 (ACSTAT0), offset 0x020 ................................................... 1150 Analog Comparator Status 1 (ACSTAT1), offset 0x040 ................................................... 1150 Analog Comparator Status 2 (ACSTAT2), offset 0x060 ................................................... 1150 Analog Comparator Control 0 (ACCTL0), offset 0x024 ................................................... 1151 Analog Comparator Control 1 (ACCTL1), offset 0x044 ................................................... 1151 Analog Comparator Control 2 (ACCTL2), offset 0x064 ................................................... 1151 July 03, 2014 39 Texas Instruments-Production Data Revision History Revision History The revision history table notes changes made between the indicated revisions of the LM3S9U90 data sheet. Table 1. Revision History Date July 2014 October 2012 January 2012 Revision Description 15852.2743 ■ ■ In System Control chapter, clarified behavior of Reset Cause (RESC) register external reset bit. ■ In Internal memory chapter, noted that the Boot Configuration (BOOTCFG) register requires a POR before committed changes to the Flash-resident registers take effect. ■ In GPIO chapter, corrected values for GPIOPCTL in the table GPIO Pins With Non-Zero Reset Values. ■ In UART chapter, clarified that the transmit interrupt is based on a transition through level. ■ In Ethernet chapter, corrected register type of Ethernet PHY Management Register 29 – Interrupt Status (MR29) to RC. ■ In Ordering and Contact Information appendix, moved orderable part numbers table to addendum. ■ Additional minor data sheet clarifications and corrections. 13440.2549 ■ 11425 In JTAG chapter, clarified JTAG-to-SWD Switching and SWD-to-JTAG Switching. Marked LM3S9U90 device as not recommended for new designs (NRND). Device is in production to support existing customers, but TI does not recommend using this part in a new design. ■ In the uDMA chapter, in the "μDMA Channel Assignments" and "Request Type Support" tables, corrected to show uDMA support for burst requests from the general-purpose timer, not single requests. ■ In the Watchdog Timers chapter, added information on servicing the watchdog timer to the Initialization and Configuration section. ■ In the General-Purpose Timers chapter, added note to the GPTMTnV registers that in 16-bit mode, only the lower 16-bits of the register can be written with a new value. Writes to the prescaler bits have no effect. ■ Corrected reset for the UART Raw Interrupt Status (UARTRIS) register. ■ In the USB chapter, clarified that the USB PHY has internal termination resistors, and thus there is no need for external resistors. ■ In the Electrical Characteristics chapter, added clarifying footnote to the GPIO Module Characteristics table. ■ Additional minor data sheet clarifications and corrections. ■ In System Control chapter: ■ – Clarified that an external LDO cannot be used. – Clarified system clock requirements when the ADC module is in operation. – Added important note to write the RCC register before the RCC2 register. In Hibernation chapter: – Changed terminology from non-volatile memory to battery-backed memory. – Numerous clarifications, including adding a section "System Implementation". 40 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Table 1. Revision History (continued) Date Revision Description – Clarified Hibernation module register reset conditions. ■ In Internal Memory chapter, clarified programming and use of the non-volatile registers. ■ In GPIO chapter, corrected "GPIO Pins With Non-Zero Reset Values" table and added note that if the same signal is assigned to two different GPIO port pins, the signal is assigned to the port with the lowest letter. ■ In EPI chapter: – Clarified table "Capabilities of Host Bus 8 and Host Bus 16 Modes". – Corrected bit and register resets for FREQ (Frequency Range) in EPI SDRAM Configuration (EPISDRAMCFG) register. – Corrected bit and register resets for MAXWAIT (Maximum Wait) in EPI Host-Bus 8 Configuration (EPIHB8CFG) and EPI Host-Bus 16 Configuration (EPIHB16CFG) registers. Also clarified bit descriptions in these registers. – Corrected bit definitions for the EPSZ and ERSZ bits in the EPI Address Map (EPIADDRMAP) register. – Corrected size of COUNT bit field in EPI Read FIFO Count (EPIRFIFOCNT) register. ■ In Timer chapter, clarified timer modes and interrupts. ■ In ADC chapter, added "ADC Input Equivalency Diagram". ■ In UART chapter, clarified interrupt behavior. ■ In SSI chapter, corrected SSIClk in the figure "Synchronous Serial Frame Format (Single Transfer)" and clarified behavior of transmit bits in interrupt registers. ■ In I2C chapter, corrected bit and register reset values for IDLE bit in I2C Master Control/Status (I2CMCS) register. ■ In USB chapter: – Clarified that when the USB module is in operation, MOSC must be provided with a clock source, and the system clock must be at least 30 MHz. – Removed MULTTRAN bit from USB Transmit Hub Address Endpoint n (USBTXHUBADDRn) and USB Receive Hub Address Endpoint n (USBRXHUBADDRn) registers. – Corrected description for the USB Device RESUME Interrupt Mask (USBDRIM) register. ■ In Analog Comparators chapter, clarified internal reference programming. ■ In Signal Tables chapter, clarified VDDC and LDO pin descriptions. ■ In Electrical Characteristics chapter: – In Maximum Ratings table, deleted parameter "Input voltage for a GPIO configured as an analog input". – In Recommended DC Operating Conditions table, corrected values for IOH parameter. – In JTAG Characteristics, table, corrected values for parameters "TCK clock Low time" and "TCK clock High time". – In LDO Regulator Characteristics table, added clarifying footnote to CLDO parameter. – In System Clock Characteristics with ADC Operation table, added clarifying footnote to Fsysadc parameter. July 03, 2014 41 Texas Instruments-Production Data Revision History Table 1. Revision History (continued) Date July 2011 March 2011 Revision 9970 9538 Description – Added "System Clock Characteristics with USB Operation" table. – In Sleep Modes AC Characteristics table, split parameter "Time to wake from interrupt" into sleep mode and deep-sleep mode parameters. – In SSI Characteristics table, corrected value for parameter "SSIClk cycle time". – In Analog Comparator Characteristics table, added parameter "Input voltage range" and corrected values for parameter "Input common mode voltage range". – In Analog Comparator Voltage Reference Characteristics table, corrected values for absolute accuracy parameters. – Deleted table "USB Controller DC Characteristics". – In Nominal Power Consumption table, added parameter for sleep mode. – In Maximum Current Consumption section, changed reference value for MOSC and temperature in tables that follow. – Deleted table "External VDDC Source Current Specifications". ■ Additional minor data sheet clarifications and corrections. ■ Corrected "Reset Sources" table. ■ Added Important Note that RCC register must be written before RCC2 register. ■ Added missing Start Calibration (CAL) bit to the Precision Internal Oscillator Calibration (PIOSCCAL) register. ■ Added missing Precision Internal Oscillator Statistics (PIOSCSTAT) register. ■ In Hibernation Module chapter, deleted section "Special Considerations When Using a 4.194304-MHz Crystal" as this content was added to the errata document. ■ Added a note that all GPIO signals are 5-V tolerant when configured as inputs except for PB0 and PB1, which are limited to 3.6 V. ■ Corrected LIN Mode bit names in UART Interrupt Clear (UARTICR) register. ■ Corrected pin number for RST and added missing pin number for ERBIAS in table "Connections for Unused Signals" (other pin tables were correct). ■ In the "Operating Characteristics" chapter: – In the "Thermal Characteristics" table, the Thermal resistance value was changed. – In the "ESD Absolute Maximum Ratings" table, the VESDCDM parameter was changed and the VESDMM parameter was deleted. ■ The "Electrical Characteristics" chapter was reorganized by module. In addition, some of the Recommended DC Operating Conditions, LDO Regulator, Clock, GPIO, EPI, Hibernation Module, ADC, and SSI characteristics were finalized. ■ Additional minor data sheet clarifications and corrections. Started tracking revision history. 42 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller About This Document This data sheet provides reference information for the LM3S9U90 microcontroller, describing the functional blocks of the system-on-chip (SoC) device designed around the ARM® Cortex™-M3 core. Audience This manual is intended for system software developers, hardware designers, and application developers. About This Manual This document is organized into sections that correspond to each major feature. Related Documents ® The following related documents are available on the Stellaris web site at www.ti.com/stellaris: ■ Stellaris® Errata ■ ARM® Cortex™-M3 Errata ■ Cortex™-M3/M4 Instruction Set Technical User's Manual ■ Stellaris® Boot Loader User's Guide ■ Stellaris® Graphics Library User's Guide ■ Stellaris® Peripheral Driver Library User's Guide ■ Stellaris® ROM User’s Guide ■ Stellaris® USB Library User's Guide The following related documents are also referenced: ■ ARM® Debug Interface V5 Architecture Specification ■ ARM® Embedded Trace Macrocell Architecture Specification ■ IEEE Standard 1149.1-Test Access Port and Boundary-Scan Architecture This documentation list was current as of publication date. Please check the web site for additional documentation, including application notes and white papers. July 03, 2014 43 Texas Instruments-Production Data About This Document Documentation Conventions This document uses the conventions shown in Table 2 on page 44. Table 2. Documentation Conventions Notation Meaning General Register Notation REGISTER APB registers are indicated in uppercase bold. For example, PBORCTL is the Power-On and Brown-Out Reset Control register. If a register name contains a lowercase n, it represents more than one register. For example, SRCRn represents any (or all) of the three Software Reset Control registers: SRCR0, SRCR1 , and SRCR2. bit A single bit in a register. bit field Two or more consecutive and related bits. offset 0xnnn A hexadecimal increment to a register's address, relative to that module's base address as specified in Table 2-4 on page 87. Register N Registers are numbered consecutively throughout the document to aid in referencing them. The register number has no meaning to software. reserved Register bits marked reserved are reserved for future use. In most cases, reserved bits are set to 0; however, user software should not rely on the value of a reserved bit. To provide software compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. yy:xx The range of register bits inclusive from xx to yy. For example, 31:15 means bits 15 through 31 in that register. Register Bit/Field Types This value in the register bit diagram indicates whether software running on the controller can change the value of the bit field. RC Software can read this field. The bit or field is cleared by hardware after reading the bit/field. RO Software can read this field. Always write the chip reset value. R/W Software can read or write this field. R/WC Software can read or write this field. Writing to it with any value clears the register. R/W1C Software can read or write this field. A write of a 0 to a W1C bit does not affect the bit value in the register. A write of a 1 clears the value of the bit in the register; the remaining bits remain unchanged. This register type is primarily used for clearing interrupt status bits where the read operation provides the interrupt status and the write of the read value clears only the interrupts being reported at the time the register was read. R/W1S Software can read or write a 1 to this field. A write of a 0 to a R/W1S bit does not affect the bit value in the register. W1C Software can write this field. A write of a 0 to a W1C bit does not affect the bit value in the register. A write of a 1 clears the value of the bit in the register; the remaining bits remain unchanged. A read of the register returns no meaningful data. This register is typically used to clear the corresponding bit in an interrupt register. WO Only a write by software is valid; a read of the register returns no meaningful data. Register Bit/Field Reset Value This value in the register bit diagram shows the bit/field value after any reset, unless noted. 0 Bit cleared to 0 on chip reset. 1 Bit set to 1 on chip reset. - Nondeterministic. Pin/Signal Notation [] Pin alternate function; a pin defaults to the signal without the brackets. pin Refers to the physical connection on the package. signal Refers to the electrical signal encoding of a pin. 44 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Table 2. Documentation Conventions (continued) Notation Meaning assert a signal Change the value of the signal from the logically False state to the logically True state. For active High signals, the asserted signal value is 1 (High); for active Low signals, the asserted signal value is 0 (Low). The active polarity (High or Low) is defined by the signal name (see SIGNAL and SIGNAL below). deassert a signal Change the value of the signal from the logically True state to the logically False state. SIGNAL Signal names are in uppercase and in the Courier font. An overbar on a signal name indicates that it is active Low. To assert SIGNAL is to drive it Low; to deassert SIGNAL is to drive it High. SIGNAL Signal names are in uppercase and in the Courier font. An active High signal has no overbar. To assert SIGNAL is to drive it High; to deassert SIGNAL is to drive it Low. Numbers X An uppercase X indicates any of several values is allowed, where X can be any legal pattern. For example, a binary value of 0X00 can be either 0100 or 0000, a hex value of 0xX is 0x0 or 0x1, and so on. 0x Hexadecimal numbers have a prefix of 0x. For example, 0x00FF is the hexadecimal number FF. All other numbers within register tables are assumed to be binary. Within conceptual information, binary numbers are indicated with a b suffix, for example, 1011b, and decimal numbers are written without a prefix or suffix. July 03, 2014 45 Texas Instruments-Production Data Architectural Overview 1 Architectural Overview ® Texas Instruments is the industry leader in bringing 32-bit capabilities and the full benefits of ARM Cortex™-M-based microcontrollers to the broadest reach of the microcontroller market. For current ® users of 8- and 16-bit MCUs, Stellaris with Cortex-M offers a direct path to the strongest ecosystem of development tools, software and knowledge in the industry. Designers who migrate to Stellaris benefit from great tools, small code footprint and outstanding performance. Even more important, designers can enter the ARM ecosystem with full confidence in a compatible roadmap from $1 to 1 GHz. For users of current 32-bit MCUs, the Stellaris family offers the industry’s first implementation of Cortex-M3 and the Thumb-2 instruction set. With blazingly-fast responsiveness, Thumb-2 technology combines both 16-bit and 32-bit instructions to deliver the best balance of code density and performance. Thumb-2 uses 26 percent less memory than pure 32-bit code to reduce system cost while delivering 25 percent better performance. The Texas Instruments Stellaris family of microcontrollers—the first ARM Cortex-M3 based controllers— brings high-performance 32-bit computing to cost-sensitive embedded microcontroller applications. 1.1 Overview The Stellaris LM3S9U90 microcontroller combines complex integration and high performance with the following feature highlights: ■ ARM Cortex-M3 Processor Core ■ High Performance: 80-MHz operation; 100 DMIPS performance ■ 384 KB single-cycle Flash memory ■ 96 KB single-cycle SRAM ® ■ Internal ROM loaded with StellarisWare software ■ External Peripheral Interface (EPI) ■ Advanced Communication Interfaces: UART, SSI, I2C, I2S, CAN, Ethernet MAC and PHY, USB ■ System Integration: general-purpose timers, watchdog timers, DMA, general-purpose I/Os ■ Analog support: analog and digital comparators, Analog-to-Digital Converters (ADC), on-chip voltage regulator ■ JTAG and ARM Serial Wire Debug (SWD) ■ 100-pin LQFP package ■ 108-ball BGA package ■ Industrial (-40°C to 85°C) temperature range Figure 1-1 on page 47 depicts the features on the Stellaris LM3S9U90 microcontroller. Note that there are two on-chip buses that connect the core to the peripherals. The Advanced Peripheral Bus (APB) bus is the legacy bus. The Advanced High-Performance Bus (AHB) bus provides better back-to-back access performance than the APB bus. 46 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Figure 1-1. Stellaris LM3S9U90 Microcontroller High-Level Block Diagram JTAG/SWD ARM® Cortex™-M3 ROM (80MHz) System Control and Clocks (w/ Precis. Osc.) DCode bus NVIC Boot Loader DriverLib AES & CRC Ethernet Boot Loader Flash (384KB) MPU ICode bus System Bus LM3S9U90 Bus Matrix SRAM (96KB) SYSTEM PERIPHERALS GeneralPurpose Timer (4) Hibernation Module External Peripheral Interface GPIOs (60) USB OTG (FS PHY) SSI (2) CAN Controller (2) Advanced Peripheral Bus (APB) Watchdog Timer (2) Advanced High-Performance Bus (AHB) DMA SERIAL PERIPHERALS UART (3) I2C (2) Ethernet MAC/PHY I2S ANALOG PERIPHERALS Analog Comparator (3) 12- Bit ADC Channels (16) July 03, 2014 47 Texas Instruments-Production Data Architectural Overview For applications requiring extreme conservation of power, the LM3S9U90 microcontroller features a battery-backed Hibernation module to efficiently power down the LM3S9U90 to a low-power state during extended periods of inactivity. With a power-up/power-down sequencer, a continuous time counter (RTC), a pair of match registers, an APB interface to the system bus, and dedicated battery-backed memory, the Hibernation module positions the LM3S9U90 microcontroller perfectly for battery applications. In addition, the LM3S9U90 microcontroller offers the advantages of ARM's widely available development tools, System-on-Chip (SoC) infrastructure IP applications, and a large user community. Additionally, the microcontroller uses ARM's Thumb®-compatible Thumb-2 instruction set to reduce memory requirements and, thereby, cost. Finally, the LM3S9U90 microcontroller is code-compatible to all members of the extensive Stellaris family; providing flexibility to fit precise needs. Texas Instruments offers a complete solution to get to market quickly, with evaluation and development boards, white papers and application notes, an easy-to-use peripheral driver library, and a strong support, sales, and distributor network. 1.2 Target Applications The Stellaris family is positioned for cost-conscious applications requiring significant control processing and connectivity capabilities such as: ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ 1.3 Gaming equipment Network appliances and switches Home and commercial site monitoring and control Electronic point-of-sale (POS) machines Motion control Medical instrumentation Remote connectivity and monitoring Test and measurement equipment Factory automation Fire and security Lighting control Transportation Features The LM3S9U90 microcontroller component features and general function are discussed in more detail in the following section. 1.3.1 ARM Cortex-M3 Processor Core All members of the Stellaris product family, including the LM3S9U90 microcontroller, are designed around an ARM Cortex-M3 processor core. The ARM Cortex-M3 processor provides the core for a high-performance, low-cost platform that meets the needs of minimal memory implementation, reduced pin count, and low power consumption, while delivering outstanding computational performance and exceptional system response to interrupts. 1.3.1.1 Processor Core (see page 68) ■ 32-bit ARM Cortex-M3 architecture optimized for small-footprint embedded applications ■ 80-MHz operation; 100 DMIPS performance ■ Outstanding processing performance combined with fast interrupt handling 48 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller ■ Thumb-2 mixed 16-/32-bit instruction set delivers the high performance expected of a 32-bit ARM core in a compact memory size usually associated with 8- and 16-bit devices, typically in the range of a few kilobytes of memory for microcontroller-class applications – Single-cycle multiply instruction and hardware divide – Atomic bit manipulation (bit-banding), delivering maximum memory utilization and streamlined peripheral control – Unaligned data access, enabling data to be efficiently packed into memory ■ Fast code execution permits slower processor clock or increases sleep mode time ■ Harvard architecture characterized by separate buses for instruction and data ■ Efficient processor core, system and memories ■ Hardware division and fast digital-signal-processing orientated multiply accumulate ■ Saturating arithmetic for signal processing ■ Deterministic, high-performance interrupt handling for time-critical applications ■ Memory protection unit (MPU) to provide a privileged mode for protected operating system functionality ■ Enhanced system debug with extensive breakpoint and trace capabilities ■ Serial Wire Debug and Serial Wire Trace reduce the number of pins required for debugging and tracing ■ Migration from the ARM7 processor family for better performance and power efficiency ■ Optimized for single-cycle Flash memory usage ■ Ultra-low power consumption with integrated sleep modes 1.3.1.2 System Timer (SysTick) (see page 111) ARM Cortex-M3 includes an integrated system timer, SysTick. SysTick provides a simple, 24-bit, clear-on-write, decrementing, wrap-on-zero counter with a flexible control mechanism. The counter can be used in several different ways, for example: ■ An RTOS tick timer that fires at a programmable rate (for example, 100 Hz) and invokes a SysTick routine ■ A high-speed alarm timer using the system clock ■ A variable rate alarm or signal timer—the duration is range-dependent on the reference clock used and the dynamic range of the counter ■ A simple counter used to measure time to completion and time used ■ An internal clock-source control based on missing/meeting durations. July 03, 2014 49 Texas Instruments-Production Data Architectural Overview 1.3.1.3 Nested Vectored Interrupt Controller (NVIC) (see page 112) The LM3S9U90 controller includes the ARM Nested Vectored Interrupt Controller (NVIC). The NVIC and Cortex-M3 prioritize and handle all exceptions in Handler Mode. The processor state is automatically stored to the stack on an exception and automatically restored from the stack at the end of the Interrupt Service Routine (ISR). The interrupt vector is fetched in parallel to the state saving, enabling efficient interrupt entry. The processor supports tail-chaining, meaning that back-to-back interrupts can be performed without the overhead of state saving and restoration. Software can set eight priority levels on 7 exceptions (system handlers) and 47 interrupts. ■ Deterministic, fast interrupt processing: always 12 cycles, or just 6 cycles with tail-chaining ■ External non-maskable interrupt signal (NMI) available for immediate execution of NMI handler for safety critical applications ■ Dynamically reprioritizable interrupts ■ Exceptional interrupt handling via hardware implementation of required register manipulations 1.3.1.4 System Control Block (SCB) (see page 114) The SCB provides system implementation information and system control, including configuration, control, and reporting of system exceptions. 1.3.1.5 Memory Protection Unit (MPU) (see page 114) The MPU supports the standard ARM7 Protected Memory System Architecture (PMSA) model. The MPU provides full support for protection regions, overlapping protection regions, access permissions, and exporting memory attributes to the system. 1.3.2 On-Chip Memory The LM3S9U90 microcontroller is integrated with the following set of on-chip memory and features: ■ 96 KB single-cycle SRAM ■ 384 KB single-cycle Flash memory up to 50 MHz; a prefetch buffer improves performance above 50 MHz ■ Internal ROM loaded with StellarisWare software: – Stellaris Peripheral Driver Library – Stellaris Boot Loader – Advanced Encryption Standard (AES) cryptography tables – Cyclic Redundancy Check (CRC) error detection functionality 1.3.2.1 SRAM (see page 321) The LM3S9U90 microcontroller provides 96 KB of single-cycle on-chip SRAM. The internal SRAM of the Stellaris devices is located at offset 0x2000.0000 of the device memory map. Because read-modify-write (RMW) operations are very time consuming, ARM has introduced bit-banding technology in the Cortex-M3 processor. With a bit-band-enabled processor, certain regions in the memory map (SRAM and peripheral space) can use address aliases to access individual bits in a single, atomic operation. Data can be transferred to and from the SRAM using the Micro Direct Memory Access Controller (µDMA). 50 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller 1.3.2.2 Flash Memory (see page 323) The LM3S9U90 microcontroller provides 384 KB of single-cycle on-chip Flash memory (above 50 MHz, the Flash memory can be accessed in a single cycle as long as the code is linear; branches incur a one-cycle stall). The Flash memory is organized as a set of 1-KB blocks that can be individually erased. Erasing a block causes the entire contents of the block to be reset to all 1s. These blocks are paired into a set of 2-KB blocks that can be individually protected. The blocks can be marked as read-only or execute-only, providing different levels of code protection. Read-only blocks cannot be erased or programmed, protecting the contents of those blocks from being modified. Execute-only blocks cannot be erased or programmed, and can only be read by the controller instruction fetch mechanism, protecting the contents of those blocks from being read by either the controller or by a debugger. 1.3.2.3 ROM (see page 321) The LM3S9U90 ROM is preprogrammed with the following software and programs: ■ Stellaris Peripheral Driver Library ■ Stellaris Boot Loader ■ Advanced Encryption Standard (AES) cryptography tables ■ Cyclic Redundancy Check (CRC) error-detection functionality The Stellaris Peripheral Driver Library is a royalty-free software library for controlling on-chip peripherals with a boot-loader capability. The library performs both peripheral initialization and control functions, with a choice of polled or interrupt-driven peripheral support. In addition, the library is designed to take full advantage of the stellar interrupt performance of the ARM Cortex-M3 core. No special pragmas or custom assembly code prologue/epilogue functions are required. For applications that require in-field programmability, the royalty-free Stellaris Boot Loader can act as an application loader and support in-field firmware updates. The Advanced Encryption Standard (AES) is a publicly defined encryption standard used by the U.S. Government. AES is a strong encryption method with reasonable performance and size. In addition, it is fast in both hardware and software, is fairly easy to implement, and requires little memory. The Texas Instruments encryption package is available with full source code, and is based on lesser general public license (LGPL) source. An LGPL means that the code can be used within an application without any copyleft implications for the application (the code does not automatically become open source). Modifications to the package source, however, must be open source. CRC (Cyclic Redundancy Check) is a technique to validate a span of data has the same contents as when previously checked. This technique can be used to validate correct receipt of messages (nothing lost or modified in transit), to validate data after decompression, to validate that Flash memory contents have not been changed, and for other cases where the data needs to be validated. A CRC is preferred over a simple checksum (e.g. XOR all bits) because it catches changes more readily. 1.3.3 External Peripheral Interface (see page 482) The External Peripheral Interface (EPI) provides access to external devices using a parallel path. Unlike communications peripherals such as SSI, UART, and I2C, the EPI is designed to act like a bus to external peripherals and memory. The EPI has the following features: July 03, 2014 51 Texas Instruments-Production Data Architectural Overview ■ 8/16/32-bit dedicated parallel bus for external peripherals and memory ■ Memory interface supports contiguous memory access independent of data bus width, thus enabling code execution directly from SDRAM, SRAM and Flash memory ■ Blocking and non-blocking reads ■ Separates processor from timing details through use of an internal write FIFO ■ Efficient transfers using Micro Direct Memory Access Controller (µDMA) – Separate channels for read and write – Read channel request asserted by programmable levels on the internal non-blocking read FIFO (NBRFIFO) – Write channel request asserted by empty on the internal write FIFO (WFIFO) The EPI supports three primary functional modes: Synchronous Dynamic Random Access Memory (SDRAM) mode, Traditional Host-Bus mode, and General-Purpose mode. The EPI module also provides custom GPIOs; however, unlike regular GPIOs, the EPI module uses a FIFO in the same way as a communication mechanism and is speed-controlled using clocking. ■ Synchronous Dynamic Random Access Memory (SDRAM) mode – Supports x16 (single data rate) SDRAM at up to 50 MHz – Supports low-cost SDRAMs up to 64 MB (512 megabits) – Includes automatic refresh and access to all banks/rows – Includes a Sleep/Standby mode to keep contents active with minimal power draw – Multiplexed address/data interface for reduced pin count ■ Host-Bus mode – Traditional x8 and x16 MCU bus interface capabilities – Similar device compatibility options as PIC, ATmega, 8051, and others – Access to SRAM, NOR Flash memory, and other devices, with up to 1 MB of addressing in unmultiplexed mode and 256 MB in multiplexed mode (512 MB in Host-Bus 16 mode with no byte selects) – Support of both muxed and de-muxed address and data – Access to a range of devices supporting the non-address FIFO x8 and x16 interface variant, with support for external FIFO (XFIFO) EMPTY and FULL signals – Speed controlled, with read and write data wait-state counters – Chip select modes include ALE, CSn, Dual CSn and ALE with dual CSn – Manual chip-enable (or use extra address pins) 52 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller ■ General-Purpose mode – Wide parallel interfaces for fast communications with CPLDs and FPGAs – Data widths up to 32 bits – Data rates up to 150 MB/second – Optional "address" sizes from 4 bits to 20 bits – Optional clock output, read/write strobes, framing (with counter-based size), and clock-enable input ■ General parallel GPIO – 1 to 32 bits, FIFOed with speed control – Useful for custom peripherals or for digital data acquisition and actuator controls 1.3.4 Serial Communications Peripherals The LM3S9U90 controller supports both asynchronous and synchronous serial communications with: ■ 10/100 Ethernet MAC and PHY ■ Two CAN 2.0 A/B controllers ■ USB 2.0 OTG/Host/Device ■ Three UARTs with IrDA and ISO 7816 support (one UART with modem flow control and status) ■ Two I2C modules ■ Two Synchronous Serial Interface modules (SSI) ■ Integrated Interchip Sound (I2S) module The following sections provide more detail on each of these communications functions. 1.3.4.1 Ethernet Controller (see page 941) Ethernet is a frame-based computer networking technology for local area networks (LANs). Ethernet has been standardized as IEEE 802.3. This specification defines a number of wiring and signaling standards for the physical layer, two means of network access at the Media Access Control (MAC)/Data Link Layer, and a common addressing format. The Stellaris Ethernet Controller consists of a fully integrated media access controller (MAC) and network physical (PHY) interface and has the following features: ■ Conforms to the IEEE 802.3-2002 specification – 10BASE-T/100BASE-TX IEEE-802.3 compliant. Requires only a dual 1:1 isolation transformer interface to the line – 10BASE-T/100BASE-TX ENDEC, 100BASE-TX scrambler/descrambler July 03, 2014 53 Texas Instruments-Production Data Architectural Overview – Full-featured auto-negotiation ■ Multiple operational modes – Full- and half-duplex 100 Mbps – Full- and half-duplex 10 Mbps – Power-saving and power-down modes ■ Highly configurable – Programmable MAC address – LED activity selection – Promiscuous mode support – CRC error-rejection control – User-configurable interrupts ■ Physical media manipulation – MDI/MDI-X cross-over support through software assist – Register-programmable transmit amplitude – Automatic polarity correction and 10BASE-T signal reception ■ Efficient transfers using Micro Direct Memory Access Controller (µDMA) – Separate channels for transmit and receive – Receive channel request asserted on packet receipt – Transmit channel request asserted on empty transmit FIFO 1.3.4.2 Controller Area Network (see page 890) Controller Area Network (CAN) is a multicast shared serial-bus standard for connecting electronic control units (ECUs). CAN was specifically designed to be robust in electromagnetically noisy environments and can utilize a differential balanced line like RS-485 or twisted-pair wire. Originally created for automotive purposes, it is now used in many embedded control applications (for example, industrial or medical). Bit rates up to 1 Mbps are possible at network lengths below 40 meters. Decreased bit rates allow longer network distances (for example, 125 Kbps at 500m). A transmitter sends a message to all CAN nodes (broadcasting). Each node decides on the basis of the identifier received whether it should process the message. The identifier also determines the priority that the message enjoys in competition for bus access. Each CAN message can transmit from 0 to 8 bytes of user information. The LM3S9U90 microcontroller includes two CAN units with the following features: ■ CAN protocol version 2.0 part A/B ■ Bit rates up to 1 Mbps 54 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller ■ 32 message objects with individual identifier masks ■ Maskable interrupt ■ Disable Automatic Retransmission mode for Time-Triggered CAN (TTCAN) applications ■ Programmable Loopback mode for self-test operation ■ Programmable FIFO mode enables storage of multiple message objects ■ Gluelessly attaches to an external CAN transceiver through the CANnTX and CANnRX signals 1.3.4.3 USB (see page 1000) Universal Serial Bus (USB) is a serial bus standard designed to allow peripherals to be connected and disconnected using a standardized interface without rebooting the system. The LM3S9U90 microcontroller supports three configurations in USB 2.0 full and low speed: USB Device, USB Host, and USB On-The-Go (negotiated on-the-go as host or device when connected to other USB-enabled systems). The USB module has the following features: ■ Complies with USB-IF certification standards ■ USB 2.0 full-speed (12 Mbps) and low-speed (1.5 Mbps) operation with integrated PHY ■ 4 transfer types: Control, Interrupt, Bulk, and Isochronous ■ 32 endpoints – 1 dedicated control IN endpoint and 1 dedicated control OUT endpoint – 15 configurable IN endpoints and 15 configurable OUT endpoints ■ 4 KB dedicated endpoint memory: one endpoint may be defined for double-buffered 1023-byte isochronous packet size ■ VBUS droop and valid ID detection and interrupt ■ Efficient transfers using Micro Direct Memory Access Controller (µDMA) – Separate channels for transmit and receive for up to three IN endpoints and three OUT endpoints – Channel requests asserted when FIFO contains required amount of data 1.3.4.4 UART (see page 709) A Universal Asynchronous Receiver/Transmitter (UART) is an integrated circuit used for RS-232C serial communications, containing a transmitter (parallel-to-serial converter) and a receiver (serial-to-parallel converter), each clocked separately. The LM3S9U90 microcontroller includes three fully programmable 16C550-type UARTs. Although the functionality is similar to a 16C550 UART, this UART design is not register compatible. The UART can generate individually masked interrupts from the Rx, Tx, modem flow control, modem status, and error conditions. The module generates a single combined interrupt when any of the interrupts are asserted and are unmasked. July 03, 2014 55 Texas Instruments-Production Data Architectural Overview The three UARTs have the following features: ■ Programmable baud-rate generator allowing speeds up to 5 Mbps for regular speed (divide by 16) and 10 Mbps for high speed (divide by 8) ■ Separate 16x8 transmit (TX) and receive (RX) FIFOs to reduce CPU interrupt service loading ■ Programmable FIFO length, including 1-byte deep operation providing conventional double-buffered interface ■ FIFO trigger levels of 1/8, 1/4, 1/2, 3/4, and 7/8 ■ Standard asynchronous communication bits for start, stop, and parity ■ Line-break generation and detection ■ Fully programmable serial interface characteristics – 5, 6, 7, or 8 data bits – Even, odd, stick, or no-parity bit generation/detection – 1 or 2 stop bit generation ■ IrDA serial-IR (SIR) encoder/decoder providing – Programmable use of IrDA Serial Infrared (SIR) or UART input/output – Support of IrDA SIR encoder/decoder functions for data rates up to 115.2 Kbps half-duplex – Support of normal 3/16 and low-power (1.41-2.23 μs) bit durations – Programmable internal clock generator enabling division of reference clock by 1 to 256 for low-power mode bit duration ■ Support for communication with ISO 7816 smart cards ■ Full modem handshake support (on UART1) ■ LIN protocol support ■ Standard FIFO-level and End-of-Transmission interrupts ■ Efficient transfers using Micro Direct Memory Access Controller (µDMA) – Separate channels for transmit and receive – Receive single request asserted when data is in the FIFO; burst request asserted at programmed FIFO level – Transmit single request asserted when there is space in the FIFO; burst request asserted at programmed FIFO level 1.3.4.5 I2C (see page 815) The Inter-Integrated Circuit (I2C) bus provides bi-directional data transfer through a two-wire design (a serial data line SDA and a serial clock line SCL). The I2C bus interfaces to external I2C devices 56 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller such as serial memory (RAMs and ROMs), networking devices, LCDs, tone generators, and so on. The I2C bus may also be used for system testing and diagnostic purposes in product development and manufacture. Each device on the I2C bus can be designated as either a master or a slave. Each I2C module supports both sending and receiving data as either a master or a slave and can operate simultaneously as both a master and a slave. Both the I2C master and slave can generate interrupts. The LM3S9U90 microcontroller includes two I2C modules with the following features: ■ Devices on the I2C bus can be designated as either a master or a slave – Supports both transmitting and receiving data as either a master or a slave – Supports simultaneous master and slave operation ■ Four I2C modes – Master transmit – Master receive – Slave transmit – Slave receive ■ Two transmission speeds: Standard (100 Kbps) and Fast (400 Kbps) ■ Master and slave interrupt generation – Master generates interrupts when a transmit or receive operation completes (or aborts due to an error) – Slave generates interrupts when data has been transferred or requested by a master or when a START or STOP condition is detected ■ Master with arbitration and clock synchronization, multimaster support, and 7-bit addressing mode 1.3.4.6 SSI (see page 773) Synchronous Serial Interface (SSI) is a four-wire bi-directional communications interface that converts data between parallel and serial. The SSI module performs serial-to-parallel conversion on data received from a peripheral device, and parallel-to-serial conversion on data transmitted to a peripheral device. The SSI module can be configured as either a master or slave device. As a slave device, the SSI module can also be configured to disable its output, which allows a master device to be coupled with multiple slave devices. The TX and RX paths are buffered with separate internal FIFOs. The SSI module also includes a programmable bit rate clock divider and prescaler to generate the output serial clock derived from the SSI module's input clock. Bit rates are generated based on the input clock and the maximum bit rate is determined by the connected peripheral. The LM3S9U90 microcontroller includes two SSI modules with the following features: ■ Programmable interface operation for Freescale SPI, MICROWIRE, or Texas Instruments synchronous serial interfaces July 03, 2014 57 Texas Instruments-Production Data Architectural Overview ■ Master or slave operation ■ Programmable clock bit rate and prescaler ■ Separate transmit and receive FIFOs, each 16 bits wide and 8 locations deep ■ Programmable data frame size from 4 to 16 bits ■ Internal loopback test mode for diagnostic/debug testing ■ Standard FIFO-based interrupts and End-of-Transmission interrupt ■ Efficient transfers using Micro Direct Memory Access Controller (µDMA) – Separate channels for transmit and receive – Receive single request asserted when data is in the FIFO; burst request asserted when FIFO contains 4 entries – Transmit single request asserted when there is space in the FIFO; burst request asserted when FIFO contains 4 entries 1.3.4.7 Inter-Integrated Circuit Sound (I2S) Interface (see page 853) The I2S interface is a configurable serial audio core that contains a transmit module and a receive module. The module is configurable for the I2S as well as Left-Justified and Right-Justified serial audio formats. Data can be in one of four modes: Stereo, Mono, Compact 16-bit Stereo and Compact 8-Bit Stereo. The transmit and receive modules each have an 8-entry audio-sample FIFO. An audio sample can consist of a Left and Right Stereo sample, a Mono sample, or a Left and Right Compact Stereo sample. In Compact 16-Bit Stereo, each FIFO entry contains both the 16-bit left and 16-bit right samples, allowing efficient data transfers and requiring less memory space. In Compact 8-bit Stereo, each FIFO entry contains an 8-bit left and an 8-bit right sample, reducing memory requirements further. Both the transmitter and receiver are capable of being a master or a slave. The Stellaris I2S interface has the following features: ■ Configurable audio format supporting I2S, Left-justification, and Right-justification ■ Configurable sample size from 8 to 32 bits ■ Mono and Stereo support ■ 8-, 16-, and 32-bit FIFO interface for packing memory ■ Independent transmit and receive 8-entry FIFOs ■ Configurable FIFO-level interrupt and µDMA requests ■ Independent transmit and receive MCLK direction control ■ Transmit and receive internal MCLK sources ■ Independent transmit and receive control for serial clock and word select 58 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller ■ MCLK and SCLK can be independently set to master or slave ■ Configurable transmit zero or last sample when FIFO empty ■ Efficient transfers using Micro Direct Memory Access Controller (µDMA) – Separate channels for transmit and receive – Burst requests – Channel requests asserted when FIFO contains required amount of data 1.3.5 System Integration The LM3S9U90 microcontroller provides a variety of standard system functions integrated into the device, including: ■ Direct Memory Access Controller (DMA) ■ System control and clocks including on-chip precision 16-MHz oscillator ■ Four 32-bit timers (up to eight 16-bit) ■ Eight Capture Compare PWM (CCP) pins ■ Lower-power battery-backed Hibernation module ■ Real-Time Clock in Hibernation module ■ Two Watchdog Timers – One timer runs off the main oscillator – One timer runs off the precision internal oscillator ■ Up to 60 GPIOs, depending on configuration – Highly flexible pin muxing allows use as GPIO or one of several peripheral functions – Independently configurable to 2, 4 or 8 mA drive capability – Up to 4 GPIOs can have 18 mA drive capability The following sections provide more detail on each of these functions. 1.3.5.1 Direct Memory Access (see page 366) The LM3S9U90 microcontroller includes a Direct Memory Access (DMA) controller, known as micro-DMA (μDMA). The μDMA controller provides a way to offload data transfer tasks from the Cortex-M3 processor, allowing for more efficient use of the processor and the available bus bandwidth. The μDMA controller can perform transfers between memory and peripherals. It has dedicated channels for each supported on-chip module and can be programmed to automatically perform transfers between peripherals and memory as the peripheral is ready to transfer more data. The μDMA controller provides the following features: ® ■ ARM PrimeCell 32-channel configurable µDMA controller ■ Support for memory-to-memory, memory-to-peripheral, and peripheral-to-memory in multiple transfer modes – Basic for simple transfer scenarios July 03, 2014 59 Texas Instruments-Production Data Architectural Overview – Ping-pong for continuous data flow – Scatter-gather for a programmable list of up to 256 arbitrary transfers initiated from a single request ■ Highly flexible and configurable channel operation – Independently configured and operated channels – Dedicated channels for supported on-chip modules – Primary and secondary channel assignments – One channel each for receive and transmit path for bidirectional modules – Dedicated channel for software-initiated transfers – Per-channel configurable priority scheme – Optional software-initiated requests for any channel ■ Two levels of priority ■ Design optimizations for improved bus access performance between µDMA controller and the processor core – µDMA controller access is subordinate to core access – RAM striping – Peripheral bus segmentation ■ Data sizes of 8, 16, and 32 bits ■ Transfer size is programmable in binary steps from 1 to 1024 ■ Source and destination address increment size of byte, half-word, word, or no increment ■ Maskable peripheral requests ■ Interrupt on transfer completion, with a separate interrupt per channel 1.3.5.2 System Control and Clocks (see page 189) System control determines the overall operation of the device. It provides information about the device, controls power-saving features, controls the clocking of the device and individual peripherals, and handles reset detection and reporting. ■ Device identification information: version, part number, SRAM size, Flash memory size, and so on ■ Power control – On-chip fixed Low Drop-Out (LDO) voltage regulator – Hibernation module handles the power-up/down 3.3 V sequencing and control for the core digital logic and analog circuits 60 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller – Low-power options for microcontroller: Sleep and Deep-sleep modes with clock gating – Low-power options for on-chip modules: software controls shutdown of individual peripherals and memory – 3.3-V supply brown-out detection and reporting via interrupt or reset ■ Multiple clock sources for microcontroller system clock – Precision Oscillator (PIOSC): On-chip resource providing a 16 MHz ±1% frequency at room temperature • 16 MHz ±3% across temperature • Can be recalibrated with 7-bit trim resolution • Software power down control for low power modes – Main Oscillator (MOSC): A frequency-accurate clock source by one of two means: an external single-ended clock source is connected to the OSC0 input pin, or an external crystal is connected across the OSC0 input and OSC1 output pins. • External crystal used with or without on-chip PLL: select supported frequencies from 1 MHz to 16.384 MHz. • External oscillator: from DC to maximum device speed – Internal 30-kHz Oscillator: on chip resource providing a 30 kHz ± 50% frequency, used during power-saving modes – 32.768-kHz external oscillator for the Hibernation Module: eliminates need for additional crystal for main clock source ■ Flexible reset sources – Power-on reset (POR) – Reset pin assertion – Brown-out reset (BOR) detector alerts to system power drops – Software reset – Watchdog timer reset – MOSC failure 1.3.5.3 Programmable Timers (see page 557) Programmable timers can be used to count or time external events that drive the Timer input pins. Each GPTM block provides two 16-bit timers/counters that can be configured to operate independently as timers or event counters, or configured to operate as one 32-bit timer or one 32-bit Real-Time Clock (RTC). Timers can also be used to trigger analog-to-digital (ADC) conversions. The General-Purpose Timer Module (GPTM) contains four GPTM blocks with the following functional options: ■ Operating modes: – 16- or 32-bit programmable one-shot timer July 03, 2014 61 Texas Instruments-Production Data Architectural Overview – 16- or 32-bit programmable periodic timer – 16-bit general-purpose timer with an 8-bit prescaler – 32-bit Real-Time Clock (RTC) when using an external 32.768-KHz clock as the input – 16-bit input-edge count- or time-capture modes – 16-bit PWM mode with software-programmable output inversion of the PWM signal ■ Count up or down ■ Eight Capture Compare PWM pins (CCP) ■ Daisy chaining of timer modules to allow a single timer to initiate multiple timing events ■ ADC event trigger ■ User-enabled stalling when the microcontroller asserts CPU Halt flag during debug (excluding RTC mode) ■ Ability to determine the elapsed time between the assertion of the timer interrupt and entry into the interrupt service routine. ■ Efficient transfers using Micro Direct Memory Access Controller (µDMA) – Dedicated channel for each timer – Burst request generated on timer interrupt 1.3.5.4 CCP Pins (see page 564) Capture Compare PWM pins (CCP) can be used by the General-Purpose Timer Module to time/count external events using the CCP pin as an input. Alternatively, the GPTM can generate a simple PWM output on the CCP pin. The LM3S9U90 microcontroller includes eight Capture Compare PWM pins (CCP) that can be programmed to operate in the following modes: ■ Capture: The GP Timer is incremented/decremented by programmed events on the CCP input. The GP Timer captures and stores the current timer value when a programmed event occurs. ■ Compare: The GP Timer is incremented/decremented by programmed events on the CCP input. The GP Timer compares the current value with a stored value and generates an interrupt when a match occurs. ■ PWM: The GP Timer is incremented/decremented by the system clock. A PWM signal is generated based on a match between the counter value and a value stored in a match register and is output on the CCP pin. 1.3.5.5 Hibernation Module (see page 293) The Hibernation module provides logic to switch power off to the main processor and peripherals and to wake on external or time-based events. The Hibernation module includes power-sequencing logic and has the following features: ■ 32-bit real-time counter (RTC) 62 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller – Two 32-bit RTC match registers for timed wake-up and interrupt generation – RTC predivider trim for making fine adjustments to the clock rate ■ Two mechanisms for power control – System power control using discrete external regulator – On-chip power control using internal switches under register control ■ Dedicated pin for waking using an external signal ■ RTC operational and hibernation memory valid as long as VBAT is valid ■ Low-battery detection, signaling, and interrupt generation ■ Clock source from a 32.768-kHz external oscillator or a 4.194304-MHz crystal; 32.768-kHz external oscillator can be used for main controller clock ■ 64 32-bit words of battery-backed memory to save state during hibernation ■ Programmable interrupts for RTC match, external wake, and low battery events 1.3.5.6 Watchdog Timers (see page 604) A watchdog timer is used to regain control when a system has failed due to a software error or to the failure of an external device to respond in the expected way. The Stellaris Watchdog Timer can generate an interrupt or a reset when a time-out value is reached. In addition, the Watchdog Timer is ARM FiRM-compliant and can be configured to generate an interrupt to the microcontroller on its first time-out, and to generate a reset signal on its second time-out. Once the Watchdog Timer has been configured, the lock register can be written to prevent the timer configuration from being inadvertently altered. The LM3S9U90 microcontroller has two Watchdog Timer modules: Watchdog Timer 0 uses the system clock for its timer clock; Watchdog Timer 1 uses the PIOSC as its timer clock. The Stellaris Watchdog Timer module has the following features: ■ 32-bit down counter with a programmable load register ■ Separate watchdog clock with an enable ■ Programmable interrupt generation logic with interrupt masking ■ Lock register protection from runaway software ■ Reset generation logic with an enable/disable ■ User-enabled stalling when the microcontroller asserts the CPU Halt flag during debug 1.3.5.7 Programmable GPIOs (see page 427) General-purpose input/output (GPIO) pins offer flexibility for a variety of connections. The Stellaris GPIO module is comprised of nine physical GPIO blocks, each corresponding to an individual GPIO port. The GPIO module is FiRM-compliant (compliant to the ARM Foundation IP for Real-Time Microcontrollers specification) and supports 0-60 programmable input/output pins. The number of GPIOs available depends on the peripherals being used (see “Signal Tables” on page 1155 for the signals available to each GPIO pin). July 03, 2014 63 Texas Instruments-Production Data Architectural Overview ■ Up to 60 GPIOs, depending on configuration ■ Highly flexible pin muxing allows use as GPIO or one of several peripheral functions ■ 5-V-tolerant in input configuration ■ Two means of port access: either Advanced High-Performance Bus (AHB) with better back-to-back access performance, or the legacy Advanced Peripheral Bus (APB) for backwards-compatibility with existing code ■ Fast toggle capable of a change every clock cycle for ports on AHB, every two clock cycles for ports on APB ■ Programmable control for GPIO interrupts – Interrupt generation masking – Edge-triggered on rising, falling, or both – Level-sensitive on High or Low values ■ Bit masking in both read and write operations through address lines ■ Can be used to initiate an ADC sample sequence ■ Pins configured as digital inputs are Schmitt-triggered ■ Programmable control for GPIO pad configuration – Weak pull-up or pull-down resistors – 2-mA, 4-mA, and 8-mA pad drive for digital communication; up to four pads can sink 18-mA for high-current applications – Slew rate control for the 8-mA drive – Open drain enables – Digital input enables 1.3.6 Analog The LM3S9U90 microcontroller provides analog functions integrated into the device, including: ■ Two 12-bit Analog-to-Digital Converters (ADC) with 16 analog input channels and a sample rate of one million samples/second ■ Three analog comparators ■ 16 digital comparators ■ On-chip voltage regulator The following provides more detail on these analog functions. 64 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller 1.3.6.1 ADC (see page 629) An analog-to-digital converter (ADC) is a peripheral that converts a continuous analog voltage to a discrete digital number. The Stellaris ADC module features 12-bit conversion resolution and supports 16 input channels plus an internal temperature sensor. Four buffered sample sequencers allow rapid sampling of up to 16 analog input sources without controller intervention. Each sample sequencer provides flexible programming with fully configurable input source, trigger events, interrupt generation, and sequencer priority. Each ADC module has a digital comparator function that allows the conversion value to be diverted to a comparison unit that provides eight digital comparators. The LM3S9U90 microcontroller provides two ADC modules with the following features: ■ 16 shared analog input channels ■ 12-bit precision ADC with an accurate 10-bit data compatibility mode ■ Single-ended and differential-input configurations ■ On-chip internal temperature sensor ■ Maximum sample rate of one million samples/second ■ Optional phase shift in sample time programmable from 22.5º to 337.5º ■ Four programmable sample conversion sequencers from one to eight entries long, with corresponding conversion result FIFOs ■ Flexible trigger control – Controller (software) – Timers – Analog Comparators – GPIO ■ Hardware averaging of up to 64 samples ■ Digital comparison unit providing eight digital comparators ■ Converter uses an internal 3-V reference or an external reference ■ Power and ground for the analog circuitry is separate from the digital power and ground ■ Efficient transfers using Micro Direct Memory Access Controller (µDMA) – Dedicated channel for each sample sequencer – ADC module uses burst requests for DMA 1.3.6.2 Analog Comparators (see page 1139) An analog comparator is a peripheral that compares two analog voltages and provides a logical output that signals the comparison result. The LM3S9U90 microcontroller provides three independent integrated analog comparators that can be configured to drive an output or generate an interrupt or ADC event. July 03, 2014 65 Texas Instruments-Production Data Architectural Overview The comparator can provide its output to a device pin, acting as a replacement for an analog comparator on the board, or it can be used to signal the application via interrupts or triggers to the ADC to cause it to start capturing a sample sequence. The interrupt generation and ADC triggering logic is separate. This means, for example, that an interrupt can be generated on a rising edge and the ADC triggered on a falling edge. The LM3S9U90 microcontroller provides three independent integrated analog comparators with the following functions: ■ Compare external pin input to external pin input or to internal programmable voltage reference ■ Compare a test voltage against any one of the following voltages: – An individual external reference voltage – A shared single external reference voltage – A shared internal reference voltage 1.3.7 JTAG and ARM Serial Wire Debug (see page 177) The Joint Test Action Group (JTAG) port is an IEEE standard that defines a Test Access Port and Boundary Scan Architecture for digital integrated circuits and provides a standardized serial interface for controlling the associated test logic. The TAP, Instruction Register (IR), and Data Registers (DR) can be used to test the interconnections of assembled printed circuit boards and obtain manufacturing information on the components. The JTAG Port also provides a means of accessing and controlling design-for-test features such as I/O pin observation and control, scan testing, and debugging. Texas Instruments replaces the ARM SW-DP and JTAG-DP with the ARM Serial Wire JTAG Debug Port (SWJ-DP) interface. The SWJ-DP interface combines the SWD and JTAG debug ports into one module providing all the normal JTAG debug and test functionality plus real-time access to system memory without halting the core or requiring any target resident code. The SWJ-DP interface has the following features: ■ IEEE 1149.1-1990 compatible Test Access Port (TAP) controller ■ Four-bit Instruction Register (IR) chain for storing JTAG instructions ■ IEEE standard instructions: BYPASS, IDCODE, SAMPLE/PRELOAD, EXTEST and INTEST ■ ARM additional instructions: APACC, DPACC and ABORT ■ Integrated ARM Serial Wire Debug (SWD) – Serial Wire JTAG Debug Port (SWJ-DP) – Flash Patch and Breakpoint (FPB) unit for implementing breakpoints – Data Watchpoint and Trace (DWT) unit for implementing watchpoints, trigger resources, and system profiling – Instrumentation Trace Macrocell (ITM) for support of printf style debugging – Trace Port Interface Unit (TPIU) for bridging to a Trace Port Analyzer 66 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller 1.3.8 Packaging and Temperature ■ Industrial-range (-40°C to 85°C) 100-pin RoHS-compliant LQFP package ■ Industrial-range (-40°C to 85°C) 108-ball RoHS-compliant BGA package 1.4 Hardware Details Details on the pins and package can be found in the following sections: ■ “Pin Diagram” on page 1153 ■ “Signal Tables” on page 1155 ■ “Operating Characteristics” on page 1221 ■ “Electrical Characteristics” on page 1222 ■ “Package Information” on page 1304 July 03, 2014 67 Texas Instruments-Production Data The Cortex-M3 Processor 2 The Cortex-M3 Processor The ARM® Cortex™-M3 processor provides a high-performance, low-cost platform that meets the system requirements of minimal memory implementation, reduced pin count, and low power consumption, while delivering outstanding computational performance and exceptional system response to interrupts. Features include: ® ■ 32-bit ARM Cortex™-M3 architecture optimized for small-footprint embedded applications ■ 80-MHz operation; 100 DMIPS performance ■ Outstanding processing performance combined with fast interrupt handling ■ Thumb-2 mixed 16-/32-bit instruction set delivers the high performance expected of a 32-bit ARM core in a compact memory size usually associated with 8- and 16-bit devices, typically in the range of a few kilobytes of memory for microcontroller-class applications – Single-cycle multiply instruction and hardware divide – Atomic bit manipulation (bit-banding), delivering maximum memory utilization and streamlined peripheral control – Unaligned data access, enabling data to be efficiently packed into memory ■ Fast code execution permits slower processor clock or increases sleep mode time ■ Harvard architecture characterized by separate buses for instruction and data ■ Efficient processor core, system and memories ■ Hardware division and fast digital-signal-processing orientated multiply accumulate ■ Saturating arithmetic for signal processing ■ Deterministic, high-performance interrupt handling for time-critical applications ■ Memory protection unit (MPU) to provide a privileged mode for protected operating system functionality ■ Enhanced system debug with extensive breakpoint and trace capabilities ■ Serial Wire Debug and Serial Wire Trace reduce the number of pins required for debugging and tracing ■ Migration from the ARM7 processor family for better performance and power efficiency ■ Optimized for single-cycle Flash memory usage ■ Ultra-low power consumption with integrated sleep modes ® The Stellaris family of microcontrollers builds on this core to bring high-performance 32-bit computing to cost-sensitive embedded microcontroller applications, such as factory automation and control, industrial control power devices, building and home automation, and stepper motor control. 68 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller This chapter provides information on the Stellaris implementation of the Cortex-M3 processor, including the programming model, the memory model, the exception model, fault handling, and power management. For technical details on the instruction set, see the Cortex™-M3/M4 Instruction Set Technical User's Manual. 2.1 Block Diagram The Cortex-M3 processor is built on a high-performance processor core, with a 3-stage pipeline Harvard architecture, making it ideal for demanding embedded applications. The processor delivers exceptional power efficiency through an efficient instruction set and extensively optimized design, providing high-end processing hardware including a range of single-cycle and SIMD multiplication and multiply-with-accumulate capabilities, saturating arithmetic and dedicated hardware division. To facilitate the design of cost-sensitive devices, the Cortex-M3 processor implements tightly coupled system components that reduce processor area while significantly improving interrupt handling and system debug capabilities. The Cortex-M3 processor implements a version of the Thumb® instruction set based on Thumb-2 technology, ensuring high code density and reduced program memory requirements. The Cortex-M3 instruction set provides the exceptional performance expected of a modern 32-bit architecture, with the high code density of 8-bit and 16-bit microcontrollers. The Cortex-M3 processor closely integrates a nested interrupt controller (NVIC), to deliver industry-leading interrupt performance. The Stellaris NVIC includes a non-maskable interrupt (NMI) and provides eight interrupt priority levels. The tight integration of the processor core and NVIC provides fast execution of interrupt service routines (ISRs), dramatically reducing interrupt latency. The hardware stacking of registers and the ability to suspend load-multiple and store-multiple operations further reduce interrupt latency. Interrupt handlers do not require any assembler stubs which removes code overhead from the ISRs. Tail-chaining optimization also significantly reduces the overhead when switching from one ISR to another. To optimize low-power designs, the NVIC integrates with the sleep modes, including Deep-sleep mode, which enables the entire device to be rapidly powered down. July 03, 2014 69 Texas Instruments-Production Data The Cortex-M3 Processor Figure 2-1. CPU Block Diagram Nested Vectored Interrupt Controller Interrupts Sleep ARM Cortex-M3 CM3 Core Debug Instructions Data Trace Port Interface Unit Memory Protection Unit Flash Patch and Breakpoint Instrumentation Data Watchpoint Trace Macrocell and Trace ROM Table Private Peripheral Bus (internal) Adv. Peripheral Bus Bus Matrix Serial Wire JTAG Debug Port Debug Access Port 2.2 Overview 2.2.1 System-Level Interface Serial Wire Output Trace Port (SWO) I-code bus D-code bus System bus The Cortex-M3 processor provides multiple interfaces using AMBA® technology to provide high-speed, low-latency memory accesses. The core supports unaligned data accesses and implements atomic bit manipulation that enables faster peripheral controls, system spinlocks, and thread-safe Boolean data handling. The Cortex-M3 processor has a memory protection unit (MPU) that provides fine-grain memory control, enabling applications to implement security privilege levels and separate code, data and stack on a task-by-task basis. 2.2.2 Integrated Configurable Debug The Cortex-M3 processor implements a complete hardware debug solution, providing high system visibility of the processor and memory through either a traditional JTAG port or a 2-pin Serial Wire Debug (SWD) port that is ideal for microcontrollers and other small package devices. The Stellaris implementation replaces the ARM SW-DP and JTAG-DP with the ARM CoreSight™-compliant Serial Wire JTAG Debug Port (SWJ-DP) interface. The SWJ-DP interface combines the SWD and JTAG debug ports into one module. See the ARM® Debug Interface V5 Architecture Specification for details on SWJ-DP. For system trace, the processor integrates an Instrumentation Trace Macrocell (ITM) alongside data watchpoints and a profiling unit. To enable simple and cost-effective profiling of the system trace events, a Serial Wire Viewer (SWV) can export a stream of software-generated messages, data trace, and profiling information through a single pin. 70 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller The Flash Patch and Breakpoint Unit (FPB) provides up to eight hardware breakpoint comparators that debuggers can use. The comparators in the FPB also provide remap functions of up to eight words in the program code in the CODE memory region. This enables applications stored in a read-only area of Flash memory to be patched in another area of on-chip SRAM or Flash memory. If a patch is required, the application programs the FPB to remap a number of addresses. When those addresses are accessed, the accesses are redirected to a remap table specified in the FPB configuration. For more information on the Cortex-M3 debug capabilities, see theARM® Debug Interface V5 Architecture Specification. 2.2.3 Trace Port Interface Unit (TPIU) The TPIU acts as a bridge between the Cortex-M3 trace data from the ITM, and an off-chip Trace Port Analyzer, as shown in Figure 2-2 on page 71. Figure 2-2. TPIU Block Diagram 2.2.4 Debug ATB Slave Port ATB Interface APB Slave Port APB Interface Asynchronous FIFO Trace Out (serializer) Serial Wire Trace Port (SWO) Cortex-M3 System Component Details The Cortex-M3 includes the following system components: ■ SysTick A 24-bit count-down timer that can be used as a Real-Time Operating System (RTOS) tick timer or as a simple counter (see “System Timer (SysTick)” on page 111). ■ Nested Vectored Interrupt Controller (NVIC) An embedded interrupt controller that supports low latency interrupt processing (see “Nested Vectored Interrupt Controller (NVIC)” on page 112). ■ System Control Block (SCB) July 03, 2014 71 Texas Instruments-Production Data The Cortex-M3 Processor The programming model interface to the processor. The SCB provides system implementation information and system control, including configuration, control, and reporting of system exceptions (see “System Control Block (SCB)” on page 114). ■ Memory Protection Unit (MPU) Improves system reliability by defining the memory attributes for different memory regions. The MPU provides up to eight different regions and an optional predefined background region (see “Memory Protection Unit (MPU)” on page 114). 2.3 Programming Model This section describes the Cortex-M3 programming model. In addition to the individual core register descriptions, information about the processor modes and privilege levels for software execution and stacks is included. 2.3.1 Processor Mode and Privilege Levels for Software Execution The Cortex-M3 has two modes of operation: ■ Thread mode Used to execute application software. The processor enters Thread mode when it comes out of reset. ■ Handler mode Used to handle exceptions. When the processor has finished exception processing, it returns to Thread mode. In addition, the Cortex-M3 has two privilege levels: ■ Unprivileged In this mode, software has the following restrictions: – Limited access to the MSR and MRS instructions and no use of the CPS instruction – No access to the system timer, NVIC, or system control block – Possibly restricted access to memory or peripherals ■ Privileged In this mode, software can use all the instructions and has access to all resources. In Thread mode, the CONTROL register (see page 86) controls whether software execution is privileged or unprivileged. In Handler mode, software execution is always privileged. Only privileged software can write to the CONTROL register to change the privilege level for software execution in Thread mode. Unprivileged software can use the SVC instruction to make a supervisor call to transfer control to privileged software. 2.3.2 Stacks The processor uses a full descending stack, meaning that the stack pointer indicates the last stacked item on the memory. When the processor pushes a new item onto the stack, it decrements the stack pointer and then writes the item to the new memory location. The processor implements two stacks: 72 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller the main stack and the process stack, with a pointer for each held in independent registers (see the SP register on page 76). In Thread mode, the CONTROL register (see page 86) controls whether the processor uses the main stack or the process stack. In Handler mode, the processor always uses the main stack. The options for processor operations are shown in Table 2-1 on page 73. Table 2-1. Summary of Processor Mode, Privilege Level, and Stack Use Processor Mode Use Privilege Level Thread Applications Privileged or unprivileged Stack Used Handler Exception handlers Always privileged a Main stack or process stack a Main stack a. See CONTROL (page 86). 2.3.3 Register Map Figure 2-3 on page 73 shows the Cortex-M3 register set. Table 2-2 on page 74 lists the Core registers. The core registers are not memory mapped and are accessed by register name, so the base address is n/a (not applicable) and there is no offset. Figure 2-3. Cortex-M3 Register Set R0 R1 R2 Low registers R3 R4 R5 R6 General-purpose registers R7 R8 R9 High registers R10 R11 R12 Stack Pointer SP (R13) Link Register LR (R14) Program Counter PC (R15) PSR PSP‡ MSP‡ ‡ Banked version of SP Program status register PRIMASK FAULTMASK Exception mask registers Special registers BASEPRI CONTROL CONTROL register July 03, 2014 73 Texas Instruments-Production Data The Cortex-M3 Processor Table 2-2. Processor Register Map Offset Type Reset - R0 R/W - Cortex General-Purpose Register 0 75 - R1 R/W - Cortex General-Purpose Register 1 75 - R2 R/W - Cortex General-Purpose Register 2 75 - R3 R/W - Cortex General-Purpose Register 3 75 - R4 R/W - Cortex General-Purpose Register 4 75 - R5 R/W - Cortex General-Purpose Register 5 75 - R6 R/W - Cortex General-Purpose Register 6 75 - R7 R/W - Cortex General-Purpose Register 7 75 - R8 R/W - Cortex General-Purpose Register 8 75 - R9 R/W - Cortex General-Purpose Register 9 75 - R10 R/W - Cortex General-Purpose Register 10 75 - R11 R/W - Cortex General-Purpose Register 11 75 - R12 R/W - Cortex General-Purpose Register 12 75 - SP R/W - Stack Pointer 76 - LR R/W 0xFFFF.FFFF Link Register 77 - PC R/W - Program Counter 78 - PSR R/W 0x0100.0000 Program Status Register 79 - PRIMASK R/W 0x0000.0000 Priority Mask Register 83 - FAULTMASK R/W 0x0000.0000 Fault Mask Register 84 - BASEPRI R/W 0x0000.0000 Base Priority Mask Register 85 - CONTROL R/W 0x0000.0000 Control Register 86 2.3.4 Description See page Name Register Descriptions This section lists and describes the Cortex-M3 registers, in the order shown in Figure 2-3 on page 73. The core registers are not memory mapped and are accessed by register name rather than offset. Note: The register type shown in the register descriptions refers to type during program execution in Thread mode and Handler mode. Debug access can differ. 74 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 1: Cortex General-Purpose Register 0 (R0) Register 2: Cortex General-Purpose Register 1 (R1) Register 3: Cortex General-Purpose Register 2 (R2) Register 4: Cortex General-Purpose Register 3 (R3) Register 5: Cortex General-Purpose Register 4 (R4) Register 6: Cortex General-Purpose Register 5 (R5) Register 7: Cortex General-Purpose Register 6 (R6) Register 8: Cortex General-Purpose Register 7 (R7) Register 9: Cortex General-Purpose Register 8 (R8) Register 10: Cortex General-Purpose Register 9 (R9) Register 11: Cortex General-Purpose Register 10 (R10) Register 12: Cortex General-Purpose Register 11 (R11) Register 13: Cortex General-Purpose Register 12 (R12) The Rn registers are 32-bit general-purpose registers for data operations and can be accessed from either privileged or unprivileged mode. Cortex General-Purpose Register 0 (R0) Type R/W, reset 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - DATA Type Reset DATA Type Reset Bit/Field Name Type Reset 31:0 DATA R/W - Description Register data. July 03, 2014 75 Texas Instruments-Production Data The Cortex-M3 Processor Register 14: Stack Pointer (SP) The Stack Pointer (SP) is register R13. In Thread mode, the function of this register changes depending on the ASP bit in the Control Register (CONTROL) register. When the ASP bit is clear, this register is the Main Stack Pointer (MSP). When the ASP bit is set, this register is the Process Stack Pointer (PSP). On reset, the ASP bit is clear, and the processor loads the MSP with the value from address 0x0000.0000. The MSP can only be accessed in privileged mode; the PSP can be accessed in either privileged or unprivileged mode. Stack Pointer (SP) Type R/W, reset 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - SP Type Reset SP Type Reset Bit/Field Name Type Reset 31:0 SP R/W - Description This field is the address of the stack pointer. 76 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 15: Link Register (LR) The Link Register (LR) is register R14, and it stores the return information for subroutines, function calls, and exceptions. LR can be accessed from either privileged or unprivileged mode. EXC_RETURN is loaded into LR on exception entry. See Table 2-10 on page 104 for the values and description. Link Register (LR) Type R/W, reset 0xFFFF.FFFF 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 7 6 5 4 3 2 1 0 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 LINK Type Reset R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 15 14 13 12 11 10 9 8 LINK Type Reset R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 Bit/Field Name Type 31:0 LINK R/W R/W 1 Reset R/W 1 Description 0xFFFF.FFFF This field is the return address. July 03, 2014 77 Texas Instruments-Production Data The Cortex-M3 Processor Register 16: Program Counter (PC) The Program Counter (PC) is register R15, and it contains the current program address. On reset, the processor loads the PC with the value of the reset vector, which is at address 0x0000.0004. Bit 0 of the reset vector is loaded into the THUMB bit of the EPSR at reset and must be 1. The PC register can be accessed in either privileged or unprivileged mode. Program Counter (PC) Type R/W, reset 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - PC Type Reset PC Type Reset Bit/Field Name Type Reset 31:0 PC R/W - Description This field is the current program address. 78 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 17: Program Status Register (PSR) Note: This register is also referred to as xPSR. The Program Status Register (PSR) has three functions, and the register bits are assigned to the different functions: ■ Application Program Status Register (APSR), bits 31:27, ■ Execution Program Status Register (EPSR), bits 26:24, 15:10 ■ Interrupt Program Status Register (IPSR), bits 6:0 The PSR, IPSR, and EPSR registers can only be accessed in privileged mode; the APSR register can be accessed in either privileged or unprivileged mode. APSR contains the current state of the condition flags from previous instruction executions. EPSR contains the Thumb state bit and the execution state bits for the If-Then (IT) instruction or the Interruptible-Continuable Instruction (ICI) field for an interrupted load multiple or store multiple instruction. Attempts to read the EPSR directly through application software using the MSR instruction always return zero. Attempts to write the EPSR using the MSR instruction in application software are always ignored. Fault handlers can examine the EPSR value in the stacked PSR to determine the operation that faulted (see “Exception Entry and Return” on page 102). IPSR contains the exception type number of the current Interrupt Service Routine (ISR). These registers can be accessed individually or as a combination of any two or all three registers, using the register name as an argument to the MSR or MRS instructions. For example, all of the registers can be read using PSR with the MRS instruction, or APSR only can be written to using APSR with the MSR instruction. page 79 shows the possible register combinations for the PSR. See the MRS and MSR instruction descriptions in the Cortex™-M3/M4 Instruction Set Technical User's Manual for more information about how to access the program status registers. Table 2-3. PSR Register Combinations Register Type PSR R/W Combination APSR, EPSR, and IPSR IEPSR RO EPSR and IPSR a, b a APSR and IPSR b APSR and EPSR IAPSR R/W EAPSR R/W a. The processor ignores writes to the IPSR bits. b. Reads of the EPSR bits return zero, and the processor ignores writes to these bits. Program Status Register (PSR) Type R/W, reset 0x0100.0000 Type Reset 31 30 29 28 27 N Z C V Q 26 25 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 RO 0 RO 0 15 14 13 12 11 10 9 ICI / IT ICI / IT Type Reset RO 0 RO 0 RO 0 24 23 22 21 20 THUMB RO 1 RO 0 RO 0 RO 0 RO 0 8 7 6 5 4 reserved RO 0 RO 0 RO 0 RO 0 RO 0 19 18 17 16 RO 0 RO 0 RO 0 RO 0 3 2 1 0 RO 0 RO 0 RO 0 reserved ISRNUM RO 0 RO 0 July 03, 2014 RO 0 RO 0 RO 0 79 Texas Instruments-Production Data The Cortex-M3 Processor Bit/Field Name Type Reset 31 N R/W 0 Description APSR Negative or Less Flag Value Description 1 The previous operation result was negative or less than. 0 The previous operation result was positive, zero, greater than, or equal. The value of this bit is only meaningful when accessing PSR or APSR. 30 Z R/W 0 APSR Zero Flag Value Description 1 The previous operation result was zero. 0 The previous operation result was non-zero. The value of this bit is only meaningful when accessing PSR or APSR. 29 C R/W 0 APSR Carry or Borrow Flag Value Description 1 The previous add operation resulted in a carry bit or the previous subtract operation did not result in a borrow bit. 0 The previous add operation did not result in a carry bit or the previous subtract operation resulted in a borrow bit. The value of this bit is only meaningful when accessing PSR or APSR. 28 V R/W 0 APSR Overflow Flag Value Description 1 The previous operation resulted in an overflow. 0 The previous operation did not result in an overflow. The value of this bit is only meaningful when accessing PSR or APSR. 27 Q R/W 0 APSR DSP Overflow and Saturation Flag Value Description 1 DSP Overflow or saturation has occurred. 0 DSP overflow or saturation has not occurred since reset or since the bit was last cleared. The value of this bit is only meaningful when accessing PSR or APSR. This bit is cleared by software using an MRS instruction. 80 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Bit/Field Name Type Reset 26:25 ICI / IT RO 0x0 Description EPSR ICI / IT status These bits, along with bits 15:10, contain the Interruptible-Continuable Instruction (ICI) field for an interrupted load multiple or store multiple instruction or the execution state bits of the IT instruction. When EPSR holds the ICI execution state, bits 26:25 are zero. The If-Then block contains up to four instructions following an IT instruction. Each instruction in the block is conditional. The conditions for the instructions are either all the same, or some can be the inverse of others. See the Cortex™-M3/M4 Instruction Set Technical User's Manual for more information. The value of this field is only meaningful when accessing PSR or EPSR. 24 THUMB RO 1 EPSR Thumb State This bit indicates the Thumb state and should always be set. The following can clear the THUMB bit: ■ The BLX, BX and POP{PC} instructions ■ Restoration from the stacked xPSR value on an exception return ■ Bit 0 of the vector value on an exception entry or reset Attempting to execute instructions when this bit is clear results in a fault or lockup. See “Lockup” on page 106 for more information. The value of this bit is only meaningful when accessing PSR or EPSR. 23:16 reserved RO 0x00 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 15:10 ICI / IT RO 0x0 EPSR ICI / IT status These bits, along with bits 26:25, contain the Interruptible-Continuable Instruction (ICI) field for an interrupted load multiple or store multiple instruction or the execution state bits of the IT instruction. When an interrupt occurs during the execution of an LDM, STM, PUSH or POP instruction, the processor stops the load multiple or store multiple instruction operation temporarily and stores the next register operand in the multiple operation to bits 15:12. After servicing the interrupt, the processor returns to the register pointed to by bits 15:12 and resumes execution of the multiple load or store instruction. When EPSR holds the ICI execution state, bits 11:10 are zero. The If-Then block contains up to four instructions following a 16-bit IT instruction. Each instruction in the block is conditional. The conditions for the instructions are either all the same, or some can be the inverse of others. See the Cortex™-M3/M4 Instruction Set Technical User's Manual for more information. The value of this field is only meaningful when accessing PSR or EPSR. 9:7 reserved RO 0x0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. July 03, 2014 81 Texas Instruments-Production Data The Cortex-M3 Processor Bit/Field Name Type Reset Description 6:0 ISRNUM RO 0x00 IPSR ISR Number This field contains the exception type number of the current Interrupt Service Routine (ISR). Value Description 0x00 Thread mode 0x01 Reserved 0x02 NMI 0x03 Hard fault 0x04 Memory management fault 0x05 Bus fault 0x06 Usage fault 0x07-0x0A Reserved 0x0B SVCall 0x0C Reserved for Debug 0x0D Reserved 0x0E PendSV 0x0F SysTick 0x10 Interrupt Vector 0 0x11 Interrupt Vector 1 ... ... 0x46 Interrupt Vector 54 0x47-0x7F Reserved See “Exception Types” on page 97 for more information. The value of this field is only meaningful when accessing PSR or IPSR. 82 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 18: Priority Mask Register (PRIMASK) The PRIMASK register prevents activation of all exceptions with programmable priority. Reset, non-maskable interrupt (NMI), and hard fault are the only exceptions with fixed priority. Exceptions should be disabled when they might impact the timing of critical tasks. This register is only accessible in privileged mode. The MSR and MRS instructions are used to access the PRIMASK register, and the CPS instruction may be used to change the value of the PRIMASK register. See the Cortex™-M3/M4 Instruction Set Technical User's Manual for more information on these instructions. For more information on exception priority levels, see “Exception Types” on page 97. Priority Mask Register (PRIMASK) Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 8 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 7 6 5 4 3 2 1 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 reserved Type Reset reserved Type Reset Bit/Field Name Type Reset 31:1 reserved RO 0x0000.000 0 PRIMASK R/W 0 RO 0 PRIMASK R/W 0 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. Priority Mask Value Description 1 Prevents the activation of all exceptions with configurable priority. 0 No effect. July 03, 2014 83 Texas Instruments-Production Data The Cortex-M3 Processor Register 19: Fault Mask Register (FAULTMASK) The FAULTMASK register prevents activation of all exceptions except for the Non-Maskable Interrupt (NMI). Exceptions should be disabled when they might impact the timing of critical tasks. This register is only accessible in privileged mode. The MSR and MRS instructions are used to access the FAULTMASK register, and the CPS instruction may be used to change the value of the FAULTMASK register. See the Cortex™-M3/M4 Instruction Set Technical User's Manual for more information on these instructions. For more information on exception priority levels, see “Exception Types” on page 97. Fault Mask Register (FAULTMASK) Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 8 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 7 6 5 4 3 2 1 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 reserved Type Reset reserved Type Reset Bit/Field Name Type Reset 31:1 reserved RO 0x0000.000 0 FAULTMASK R/W 0 RO 0 FAULTMASK R/W 0 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. Fault Mask Value Description 1 Prevents the activation of all exceptions except for NMI. 0 No effect. The processor clears the FAULTMASK bit on exit from any exception handler except the NMI handler. 84 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 20: Base Priority Mask Register (BASEPRI) The BASEPRI register defines the minimum priority for exception processing. When BASEPRI is set to a nonzero value, it prevents the activation of all exceptions with the same or lower priority level as the BASEPRI value. Exceptions should be disabled when they might impact the timing of critical tasks. This register is only accessible in privileged mode. For more information on exception priority levels, see “Exception Types” on page 97. Base Priority Mask Register (BASEPRI) Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 8 7 6 5 4 3 2 1 0 RO 0 R/W 0 R/W 0 RO 0 RO 0 RO 0 RO 0 reserved Type Reset reserved Type Reset BASEPRI RO 0 Bit/Field Name Type Reset 31:8 reserved RO 0x0000.00 7:5 BASEPRI R/W 0x0 R/W 0 reserved RO 0 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. Base Priority Any exception that has a programmable priority level with the same or lower priority as the value of this field is masked. The PRIMASK register can be used to mask all exceptions with programmable priority levels. Higher priority exceptions have lower priority levels. Value Description 4:0 reserved RO 0x0 0x0 All exceptions are unmasked. 0x1 All exceptions with priority level 1-7 are masked. 0x2 All exceptions with priority level 2-7 are masked. 0x3 All exceptions with priority level 3-7 are masked. 0x4 All exceptions with priority level 4-7 are masked. 0x5 All exceptions with priority level 5-7 are masked. 0x6 All exceptions with priority level 6-7 are masked. 0x7 All exceptions with priority level 7 are masked. Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. July 03, 2014 85 Texas Instruments-Production Data The Cortex-M3 Processor Register 21: Control Register (CONTROL) The CONTROL register controls the stack used and the privilege level for software execution when the processor is in Thread mode. This register is only accessible in privileged mode. Handler mode always uses MSP, so the processor ignores explicit writes to the ASP bit of the CONTROL register when in Handler mode. The exception entry and return mechanisms automatically update the CONTROL register based on the EXC_RETURN value (see Table 2-10 on page 104). In an OS environment, threads running in Thread mode should use the process stack and the kernel and exception handlers should use the main stack. By default, Thread mode uses MSP. To switch the stack pointer used in Thread mode to PSP, either use the MSR instruction to set the ASP bit, as detailed in the Cortex™-M3/M4 Instruction Set Technical User's Manual, or perform an exception return to Thread mode with the appropriate EXC_RETURN value, as shown in Table 2-10 on page 104. Note: When changing the stack pointer, software must use an ISB instruction immediately after the MSR instruction, ensuring that instructions after the ISB execute use the new stack pointer. See the Cortex™-M3/M4 Instruction Set Technical User's Manual. Control Register (CONTROL) Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 8 7 6 5 4 3 2 1 0 ASP TMPL RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 R/W 0 R/W 0 reserved Type Reset reserved Type Reset Bit/Field Name Type Reset 31:2 reserved RO 0x0000.000 1 ASP R/W 0 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. Active Stack Pointer Value Description 1 PSP is the current stack pointer. 0 MSP is the current stack pointer In Handler mode, this bit reads as zero and ignores writes. The Cortex-M3 updates this bit automatically on exception return. 0 TMPL R/W 0 Thread Mode Privilege Level Value Description 1 Unprivileged software can be executed in Thread mode. 0 Only privileged software can be executed in Thread mode. 86 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller 2.3.5 Exceptions and Interrupts The Cortex-M3 processor supports interrupts and system exceptions. The processor and the Nested Vectored Interrupt Controller (NVIC) prioritize and handle all exceptions. An exception changes the normal flow of software control. The processor uses Handler mode to handle all exceptions except for reset. See “Exception Entry and Return” on page 102 for more information. The NVIC registers control interrupt handling. See “Nested Vectored Interrupt Controller (NVIC)” on page 112 for more information. 2.3.6 Data Types The Cortex-M3 supports 32-bit words, 16-bit halfwords, and 8-bit bytes. The processor also supports 64-bit data transfer instructions. All instruction and data memory accesses are little endian. See “Memory Regions, Types and Attributes” on page 89 for more information. 2.4 Memory Model This section describes the processor memory map, the behavior of memory accesses, and the bit-banding features. The processor has a fixed memory map that provides up to 4 GB of addressable memory. The memory map for the LM3S9U90 controller is provided in Table 2-4 on page 87. In this manual, register addresses are given as a hexadecimal increment, relative to the module’s base address as shown in the memory map. The regions for SRAM and peripherals include bit-band regions. Bit-banding provides atomic operations to bit data (see “Bit-Banding” on page 92). The processor reserves regions of the Private peripheral bus (PPB) address range for core peripheral registers (see “Cortex-M3 Peripherals” on page 111). Note: Within the memory map, all reserved space returns a bus fault when read or written. Table 2-4. Memory Map Start End Description For details, see page ... 0x0000.0000 0x0005.FFFF On-chip Flash 330 0x0006.0000 0x00FF.FFFF Reserved - 0x0100.0000 0x1FFF.FFFF Reserved for ROM 321 0x2000.0000 0x2001.FFFF Bit-banded on-chip SRAM 321 0x2002.0000 0x21FF.FFFF Reserved - 0x2200.0000 0x222F.FFFF Bit-band alias of bit-banded on-chip SRAM starting at 0x2000.0000 321 0x2230.0000 0x3FFF.FFFF Reserved - 0x4000.0000 0x4000.0FFF Watchdog timer 0 607 0x4000.1000 0x4000.1FFF Watchdog timer 1 607 0x4000.2000 0x4000.3FFF Reserved - 0x4000.4000 0x4000.4FFF GPIO Port A 439 0x4000.5000 0x4000.5FFF GPIO Port B 439 0x4000.6000 0x4000.6FFF GPIO Port C 439 Memory FiRM Peripherals July 03, 2014 87 Texas Instruments-Production Data The Cortex-M3 Processor Table 2-4. Memory Map (continued) Start End Description For details, see page ... 0x4000.7000 0x4000.7FFF GPIO Port D 439 0x4000.8000 0x4000.8FFF SSI0 787 0x4000.9000 0x4000.9FFF SSI1 787 0x4000.A000 0x4000.BFFF Reserved - 0x4000.C000 0x4000.CFFF UART0 723 0x4000.D000 0x4000.DFFF UART1 723 0x4000.E000 0x4000.EFFF UART2 723 0x4000.F000 0x4001.FFFF Reserved - 0x4002.0FFF I2C 0 831 0x4002.1000 0x4002.1FFF I2C 831 0x4002.2000 0x4002.3FFF Reserved - 0x4002.4000 0x4002.4FFF GPIO Port E 439 0x4002.5000 0x4002.5FFF GPIO Port F 439 0x4002.6000 0x4002.6FFF GPIO Port G 439 0x4002.7000 0x4002.7FFF GPIO Port H 439 0x4002.8000 0x4002.FFFF Reserved - 0x4003.0000 0x4003.0FFF Timer 0 573 0x4003.1000 0x4003.1FFF Timer 1 573 0x4003.2000 0x4003.2FFF Timer 2 573 0x4003.3000 0x4003.3FFF Timer 3 573 0x4003.4000 0x4003.7FFF Reserved - 0x4003.8000 0x4003.8FFF ADC0 651 0x4003.9000 0x4003.9FFF ADC1 651 0x4003.A000 0x4003.BFFF Reserved - 0x4003.C000 0x4003.CFFF Analog Comparators 1139 0x4003.D000 0x4003.DFFF GPIO Port J 439 0x4003.E000 0x4003.FFFF Reserved - 0x4004.0000 0x4004.0FFF CAN0 Controller 910 0x4004.1000 0x4004.1FFF CAN1 Controller 910 0x4004.2000 0x4004.7FFF Reserved - 0x4004.8000 0x4004.8FFF Ethernet Controller 954 0x4004.9000 0x4004.FFFF Reserved - 0x4005.0000 0x4005.0FFF USB 1027 0x4005.1000 0x4005.3FFF Reserved - 0x4005.4000 0x4005.4FFF I2S0 865 0x4005.5000 0x4005.7FFF Reserved - 0x4005.8000 0x4005.8FFF GPIO Port A (AHB aperture) 439 0x4005.9000 0x4005.9FFF GPIO Port B (AHB aperture) 439 0x4005.A000 0x4005.AFFF GPIO Port C (AHB aperture) 439 0x4005.B000 0x4005.BFFF GPIO Port D (AHB aperture) 439 Peripherals 0x4002.0000 1 88 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Table 2-4. Memory Map (continued) Start End Description For details, see page ... 0x4005.C000 0x4005.CFFF GPIO Port E (AHB aperture) 439 0x4005.D000 0x4005.DFFF GPIO Port F (AHB aperture) 439 0x4005.E000 0x4005.EFFF GPIO Port G (AHB aperture) 439 0x4005.F000 0x4005.FFFF GPIO Port H (AHB aperture) 439 0x4006.0000 0x4006.0FFF GPIO Port J (AHB aperture) 439 0x4006.1000 0x400C.FFFF Reserved - 0x400D.0000 0x400D.0FFF EPI 0 513 0x400D.1000 0x400F.BFFF Reserved - 0x400F.C000 0x400F.CFFF Hibernation Module 303 0x400F.D000 0x400F.DFFF Flash memory control 330 0x400F.E000 0x400F.EFFF System control 207 0x400F.F000 0x400F.FFFF µDMA 388 0x4010.0000 0x41FF.FFFF Reserved - 0x4200.0000 0x43FF.FFFF Bit-banded alias of 0x4000.0000 through 0x400F.FFFF - 0x4400.0000 0x5FFF.FFFF Reserved - 0x6000.0000 0xDFFF.FFFF EPI0 mapped peripheral and RAM - 0xE000.0000 0xE000.0FFF Instrumentation Trace Macrocell (ITM) 70 0xE000.1000 0xE000.1FFF Data Watchpoint and Trace (DWT) 70 0xE000.2000 0xE000.2FFF Flash Patch and Breakpoint (FPB) 70 0xE000.3000 0xE000.DFFF Reserved - 0xE000.E000 0xE000.EFFF Cortex-M3 Peripherals (SysTick, NVIC, MPU and SCB) 119 0xE000.F000 0xE003.FFFF Reserved - 0xE004.0000 0xE004.0FFF Trace Port Interface Unit (TPIU) 71 0xE004.1000 0xFFFF.FFFF Reserved - Private Peripheral Bus 2.4.1 Memory Regions, Types and Attributes The memory map and the programming of the MPU split the memory map into regions. Each region has a defined memory type, and some regions have additional memory attributes. The memory type and attributes determine the behavior of accesses to the region. The memory types are: ■ Normal: The processor can re-order transactions for efficiency and perform speculative reads. ■ Device: The processor preserves transaction order relative to other transactions to Device or Strongly Ordered memory. ■ Strongly Ordered: The processor preserves transaction order relative to all other transactions. The different ordering requirements for Device and Strongly Ordered memory mean that the memory system can buffer a write to Device memory but must not buffer a write to Strongly Ordered memory. July 03, 2014 89 Texas Instruments-Production Data The Cortex-M3 Processor An additional memory attribute is Execute Never (XN), which means the processor prevents instruction accesses. A fault exception is generated only on execution of an instruction executed from an XN region. 2.4.2 Memory System Ordering of Memory Accesses For most memory accesses caused by explicit memory access instructions, the memory system does not guarantee that the order in which the accesses complete matches the program order of the instructions, providing the order does not affect the behavior of the instruction sequence. Normally, if correct program execution depends on two memory accesses completing in program order, software must insert a memory barrier instruction between the memory access instructions (see “Software Ordering of Memory Accesses” on page 91). However, the memory system does guarantee ordering of accesses to Device and Strongly Ordered memory. For two memory access instructions A1 and A2, if both A1 and A2 are accesses to either Device or Strongly Ordered memory, and if A1 occurs before A2 in program order, A1 is always observed before A2. 2.4.3 Behavior of Memory Accesses Table 2-5 on page 90 shows the behavior of accesses to each region in the memory map. See “Memory Regions, Types and Attributes” on page 89 for more information on memory types and the XN attribute. Stellaris devices may have reserved memory areas within the address ranges shown below (refer to Table 2-4 on page 87 for more information). Table 2-5. Memory Access Behavior Address Range Memory Region Memory Type Execute Never (XN) Description 0x0000.0000 - 0x1FFF.FFFF Code Normal - This executable region is for program code. Data can also be stored here. 0x2000.0000 - 0x3FFF.FFFF SRAM Normal - This executable region is for data. Code can also be stored here. This region includes bit band and bit band alias areas (see Table 2-6 on page 92). 0x4000.0000 - 0x5FFF.FFFF Peripheral Device XN This region includes bit band and bit band alias areas (see Table 2-7 on page 92). 0x6000.0000 - 0x9FFF.FFFF External RAM Normal - This executable region is for data. 0xA000.0000 - 0xDFFF.FFFF External device Device XN This region is for external device memory. 0xE000.0000- 0xE00F.FFFF Private peripheral bus Strongly Ordered XN This region includes the NVIC, system timer, and system control block. 0xE010.0000- 0xFFFF.FFFF Reserved - - - The Code, SRAM, and external RAM regions can hold programs. However, it is recommended that programs always use the Code region because the Cortex-M3 has separate buses that can perform instruction fetches and data accesses simultaneously. The MPU can override the default memory access behavior described in this section. For more information, see “Memory Protection Unit (MPU)” on page 114. The Cortex-M3 prefetches instructions ahead of execution and speculatively prefetches from branch target addresses. 90 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller 2.4.4 Software Ordering of Memory Accesses The order of instructions in the program flow does not always guarantee the order of the corresponding memory transactions for the following reasons: ■ The processor can reorder some memory accesses to improve efficiency, providing this does not affect the behavior of the instruction sequence. ■ The processor has multiple bus interfaces. ■ Memory or devices in the memory map have different wait states. ■ Some memory accesses are buffered or speculative. “Memory System Ordering of Memory Accesses” on page 90 describes the cases where the memory system guarantees the order of memory accesses. Otherwise, if the order of memory accesses is critical, software must include memory barrier instructions to force that ordering. The Cortex-M3 has the following memory barrier instructions: ■ The Data Memory Barrier (DMB) instruction ensures that outstanding memory transactions complete before subsequent memory transactions. ■ The Data Synchronization Barrier (DSB) instruction ensures that outstanding memory transactions complete before subsequent instructions execute. ■ The Instruction Synchronization Barrier (ISB) instruction ensures that the effect of all completed memory transactions is recognizable by subsequent instructions. Memory barrier instructions can be used in the following situations: ■ MPU programming – If the MPU settings are changed and the change must be effective on the very next instruction, use a DSB instruction to ensure the effect of the MPU takes place immediately at the end of context switching. – Use an ISB instruction to ensure the new MPU setting takes effect immediately after programming the MPU region or regions, if the MPU configuration code was accessed using a branch or call. If the MPU configuration code is entered using exception mechanisms, then an ISB instruction is not required. ■ Vector table If the program changes an entry in the vector table and then enables the corresponding exception, use a DMB instruction between the operations. The DMB instruction ensures that if the exception is taken immediately after being enabled, the processor uses the new exception vector. ■ Self-modifying code If a program contains self-modifying code, use an ISB instruction immediately after the code modification in the program. The ISB instruction ensures subsequent instruction execution uses the updated program. ■ Memory map switching July 03, 2014 91 Texas Instruments-Production Data The Cortex-M3 Processor If the system contains a memory map switching mechanism, use a DSB instruction after switching the memory map in the program. The DSB instruction ensures subsequent instruction execution uses the updated memory map. ■ Dynamic exception priority change When an exception priority has to change when the exception is pending or active, use DSB instructions after the change. The change then takes effect on completion of the DSB instruction. Memory accesses to Strongly Ordered memory, such as the System Control Block, do not require the use of DMB instructions. For more information on the memory barrier instructions, see the Cortex™-M3/M4 Instruction Set Technical User's Manual. 2.4.5 Bit-Banding A bit-band region maps each word in a bit-band alias region to a single bit in the bit-band region. The bit-band regions occupy the lowest 1 MB of the SRAM and peripheral memory regions. Accesses to the 32-MB SRAM alias region map to the 1-MB SRAM bit-band region, as shown in Table 2-6 on page 92. Accesses to the 32-MB peripheral alias region map to the 1-MB peripheral bit-band region, as shown in Table 2-7 on page 92. For the specific address range of the bit-band regions, see Table 2-4 on page 87. Note: A word access to the SRAM or the peripheral bit-band alias region maps to a single bit in the SRAM or peripheral bit-band region. A word access to a bit band address results in a word access to the underlying memory, and similarly for halfword and byte accesses. This allows bit band accesses to match the access requirements of the underlying peripheral. Table 2-6. SRAM Memory Bit-Banding Regions Address Range Memory Region Instruction and Data Accesses Start End 0x2000.0000 0x2001.FFFF SRAM bit-band region Direct accesses to this memory range behave as SRAM memory accesses, but this region is also bit addressable through bit-band alias. 0x2200.0000 0x222F.FFFF SRAM bit-band alias Data accesses to this region are remapped to bit band region. A write operation is performed as read-modify-write. Instruction accesses are not remapped. Table 2-7. Peripheral Memory Bit-Banding Regions Address Range Memory Region Instruction and Data Accesses 0x400F.FFFF Peripheral bit-band region Direct accesses to this memory range behave as peripheral memory accesses, but this region is also bit addressable through bit-band alias. 0x43FF.FFFF Peripheral bit-band alias Data accesses to this region are remapped to bit band region. A write operation is performed as read-modify-write. Instruction accesses are not permitted. Start End 0x4000.0000 0x4200.0000 The following formula shows how the alias region maps onto the bit-band region: bit_word_offset = (byte_offset x 32) + (bit_number x 4) 92 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller bit_word_addr = bit_band_base + bit_word_offset where: bit_word_offset The position of the target bit in the bit-band memory region. bit_word_addr The address of the word in the alias memory region that maps to the targeted bit. bit_band_base The starting address of the alias region. byte_offset The number of the byte in the bit-band region that contains the targeted bit. bit_number The bit position, 0-7, of the targeted bit. Figure 2-4 on page 94 shows examples of bit-band mapping between the SRAM bit-band alias region and the SRAM bit-band region: ■ The alias word at 0x23FF.FFE0 maps to bit 0 of the bit-band byte at 0x200F.FFFF: 0x23FF.FFE0 = 0x2200.0000 + (0x000F.FFFF*32) + (0*4) ■ The alias word at 0x23FF.FFFC maps to bit 7 of the bit-band byte at 0x200F.FFFF: 0x23FF.FFFC = 0x2200.0000 + (0x000F.FFFF*32) + (7*4) ■ The alias word at 0x2200.0000 maps to bit 0 of the bit-band byte at 0x2000.0000: 0x2200.0000 = 0x2200.0000 + (0*32) + (0*4) ■ The alias word at 0x2200.001C maps to bit 7 of the bit-band byte at 0x2000.0000: 0x2200.001C = 0x2200.0000+ (0*32) + (7*4) July 03, 2014 93 Texas Instruments-Production Data The Cortex-M3 Processor Figure 2-4. Bit-Band Mapping 32-MB Alias Region 0x23FF.FFFC 0x23FF.FFF8 0x23FF.FFF4 0x23FF.FFF0 0x23FF.FFEC 0x23FF.FFE8 0x23FF.FFE4 0x23FF.FFE0 0x2200.001C 0x2200.0018 0x2200.0014 0x2200.0010 0x2200.000C 0x2200.0008 0x2200.0004 0x2200.0000 7 3 1-MB SRAM Bit-Band Region 7 6 5 4 3 2 1 0 7 6 0x200F.FFFF 7 6 5 4 3 2 0x2000.0003 2.4.5.1 5 4 3 2 1 0 7 6 0x200F.FFFE 1 0 7 6 5 4 3 2 5 4 3 2 1 0 6 0x200F.FFFD 1 0 0x2000.0002 7 6 5 4 3 2 0x2000.0001 5 4 2 1 0 1 0 0x200F.FFFC 1 0 7 6 5 4 3 2 0x2000.0000 Directly Accessing an Alias Region Writing to a word in the alias region updates a single bit in the bit-band region. Bit 0 of the value written to a word in the alias region determines the value written to the targeted bit in the bit-band region. Writing a value with bit 0 set writes a 1 to the bit-band bit, and writing a value with bit 0 clear writes a 0 to the bit-band bit. Bits 31:1 of the alias word have no effect on the bit-band bit. Writing 0x01 has the same effect as writing 0xFF. Writing 0x00 has the same effect as writing 0x0E. When reading a word in the alias region, 0x0000.0000 indicates that the targeted bit in the bit-band region is clear and 0x0000.0001 indicates that the targeted bit in the bit-band region is set. 2.4.5.2 Directly Accessing a Bit-Band Region “Behavior of Memory Accesses” on page 90 describes the behavior of direct byte, halfword, or word accesses to the bit-band regions. 2.4.6 Data Storage The processor views memory as a linear collection of bytes numbered in ascending order from zero. For example, bytes 0-3 hold the first stored word, and bytes 4-7 hold the second stored word. Data is stored in little-endian format, with the least-significant byte (lsbyte) of a word stored at the lowest-numbered byte, and the most-significant byte (msbyte) stored at the highest-numbered byte. Figure 2-5 on page 95 illustrates how data is stored. 94 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Figure 2-5. Data Storage Memory 7 Register 0 31 2.4.7 Address A B0 A+1 B1 A+2 B2 A+3 B3 lsbyte 24 23 B3 16 15 B2 8 7 B1 0 B0 msbyte Synchronization Primitives The Cortex-M3 instruction set includes pairs of synchronization primitives which provide a non-blocking mechanism that a thread or process can use to obtain exclusive access to a memory location. Software can use these primitives to perform a guaranteed read-modify-write memory update sequence or for a semaphore mechanism. A pair of synchronization primitives consists of: ■ A Load-Exclusive instruction, which is used to read the value of a memory location and requests exclusive access to that location. ■ A Store-Exclusive instruction, which is used to attempt to write to the same memory location and returns a status bit to a register. If this status bit is clear, it indicates that the thread or process gained exclusive access to the memory and the write succeeds; if this status bit is set, it indicates that the thread or process did not gain exclusive access to the memory and no write was performed. The pairs of Load-Exclusive and Store-Exclusive instructions are: ■ The word instructions LDREX and STREX ■ The halfword instructions LDREXH and STREXH ■ The byte instructions LDREXB and STREXB Software must use a Load-Exclusive instruction with the corresponding Store-Exclusive instruction. To perform an exclusive read-modify-write of a memory location, software must: 1. Use a Load-Exclusive instruction to read the value of the location. 2. Modify the value, as required. 3. Use a Store-Exclusive instruction to attempt to write the new value back to the memory location. 4. Test the returned status bit. If the status bit is clear, the read-modify-write completed successfully. If the status bit is set, no write was performed, which indicates that the value returned at step 1 might be out of date. The software must retry the entire read-modify-write sequence. Software can use the synchronization primitives to implement a semaphore as follows: July 03, 2014 95 Texas Instruments-Production Data The Cortex-M3 Processor 1. Use a Load-Exclusive instruction to read from the semaphore address to check whether the semaphore is free. 2. If the semaphore is free, use a Store-Exclusive to write the claim value to the semaphore address. 3. If the returned status bit from step 2 indicates that the Store-Exclusive succeeded, then the software has claimed the semaphore. However, if the Store-Exclusive failed, another process might have claimed the semaphore after the software performed step 1. The Cortex-M3 includes an exclusive access monitor that tags the fact that the processor has executed a Load-Exclusive instruction. The processor removes its exclusive access tag if: ■ It executes a CLREX instruction. ■ It executes a Store-Exclusive instruction, regardless of whether the write succeeds. ■ An exception occurs, which means the processor can resolve semaphore conflicts between different threads. For more information about the synchronization primitive instructions, see the Cortex™-M3/M4 Instruction Set Technical User's Manual. 2.5 Exception Model The ARM Cortex-M3 processor and the Nested Vectored Interrupt Controller (NVIC) prioritize and handle all exceptions in Handler Mode. The processor state is automatically stored to the stack on an exception and automatically restored from the stack at the end of the Interrupt Service Routine (ISR). The vector is fetched in parallel to the state saving, enabling efficient interrupt entry. The processor supports tail-chaining, which enables back-to-back interrupts to be performed without the overhead of state saving and restoration. Table 2-8 on page 98 lists all exception types. Software can set eight priority levels on seven of these exceptions (system handlers) as well as on 47 interrupts (listed in Table 2-9 on page 99). Priorities on the system handlers are set with the NVIC System Handler Priority n (SYSPRIn) registers. Interrupts are enabled through the NVIC Interrupt Set Enable n (ENn) register and prioritized with the NVIC Interrupt Priority n (PRIn) registers. Priorities can be grouped by splitting priority levels into preemption priorities and subpriorities. All the interrupt registers are described in “Nested Vectored Interrupt Controller (NVIC)” on page 112. Internally, the highest user-programmable priority (0) is treated as fourth priority, after a Reset, Non-Maskable Interrupt (NMI), and a Hard Fault, in that order. Note that 0 is the default priority for all the programmable priorities. Important: After a write to clear an interrupt source, it may take several processor cycles for the NVIC to see the interrupt source de-assert. Thus if the interrupt clear is done as the last action in an interrupt handler, it is possible for the interrupt handler to complete while the NVIC sees the interrupt as still asserted, causing the interrupt handler to be re-entered errantly. This situation can be avoided by either clearing the interrupt source at the beginning of the interrupt handler or by performing a read or write after the write to clear the interrupt source (and flush the write buffer). See “Nested Vectored Interrupt Controller (NVIC)” on page 112 for more information on exceptions and interrupts. 96 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller 2.5.1 Exception States Each exception is in one of the following states: ■ Inactive. The exception is not active and not pending. ■ Pending. The exception is waiting to be serviced by the processor. An interrupt request from a peripheral or from software can change the state of the corresponding interrupt to pending. ■ Active. An exception that is being serviced by the processor but has not completed. Note: An exception handler can interrupt the execution of another exception handler. In this case, both exceptions are in the active state. ■ Active and Pending. The exception is being serviced by the processor, and there is a pending exception from the same source. 2.5.2 Exception Types The exception types are: ■ Reset. Reset is invoked on power up or a warm reset. The exception model treats reset as a special form of exception. When reset is asserted, the operation of the processor stops, potentially at any point in an instruction. When reset is deasserted, execution restarts from the address provided by the reset entry in the vector table. Execution restarts as privileged execution in Thread mode. ■ NMI. A non-maskable Interrupt (NMI) can be signaled using the NMI signal or triggered by software using the Interrupt Control and State (INTCTRL) register. This exception has the highest priority other than reset. NMI is permanently enabled and has a fixed priority of -2. NMIs cannot be masked or prevented from activation by any other exception or preempted by any exception other than reset. ■ Hard Fault. A hard fault is an exception that occurs because of an error during exception processing, or because an exception cannot be managed by any other exception mechanism. Hard faults have a fixed priority of -1, meaning they have higher priority than any exception with configurable priority. ■ Memory Management Fault. A memory management fault is an exception that occurs because of a memory protection related fault, including access violation and no match. The MPU or the fixed memory protection constraints determine this fault, for both instruction and data memory transactions. This fault is used to abort instruction accesses to Execute Never (XN) memory regions, even if the MPU is disabled. ■ Bus Fault. A bus fault is an exception that occurs because of a memory-related fault for an instruction or data memory transaction such as a prefetch fault or a memory access fault. This fault can be enabled or disabled. ■ Usage Fault. A usage fault is an exception that occurs because of a fault related to instruction execution, such as: – An undefined instruction – An illegal unaligned access – Invalid state on instruction execution July 03, 2014 97 Texas Instruments-Production Data The Cortex-M3 Processor – An error on exception return An unaligned address on a word or halfword memory access or division by zero can cause a usage fault when the core is properly configured. ■ SVCall. A supervisor call (SVC) is an exception that is triggered by the SVC instruction. In an OS environment, applications can use SVC instructions to access OS kernel functions and device drivers. ■ Debug Monitor. This exception is caused by the debug monitor (when not halting). This exception is only active when enabled. This exception does not activate if it is a lower priority than the current activation. ■ PendSV. PendSV is a pendable, interrupt-driven request for system-level service. In an OS environment, use PendSV for context switching when no other exception is active. PendSV is triggered using the Interrupt Control and State (INTCTRL) register. ■ SysTick. A SysTick exception is an exception that the system timer generates when it reaches zero when it is enabled to generate an interrupt. Software can also generate a SysTick exception using the Interrupt Control and State (INTCTRL) register. In an OS environment, the processor can use this exception as system tick. ■ Interrupt (IRQ). An interrupt, or IRQ, is an exception signaled by a peripheral or generated by a software request and fed through the NVIC (prioritized). All interrupts are asynchronous to instruction execution. In the system, peripherals use interrupts to communicate with the processor. Table 2-9 on page 99 lists the interrupts on the LM3S9U90 controller. For an asynchronous exception, other than reset, the processor can execute another instruction between when the exception is triggered and when the processor enters the exception handler. Privileged software can disable the exceptions that Table 2-8 on page 98 shows as having configurable priority (see the SYSHNDCTRL register on page 155 and the DIS0 register on page 128). For more information about hard faults, memory management faults, bus faults, and usage faults, see “Fault Handling” on page 104. Table 2-8. Exception Types Exception Type a Vector Number Priority Vector Address or b Offset - 0 - 0x0000.0000 Stack top is loaded from the first entry of the vector table on reset. Reset 1 -3 (highest) 0x0000.0004 Asynchronous Non-Maskable Interrupt (NMI) 2 -2 0x0000.0008 Asynchronous Hard Fault 3 -1 0x0000.000C - c 0x0000.0010 Synchronous c 0x0000.0014 Synchronous when precise and asynchronous when imprecise c Synchronous Memory Management 4 programmable Bus Fault 5 programmable Usage Fault 6 programmable 0x0000.0018 7-10 - - - Activation c c Reserved SVCall 11 programmable 0x0000.002C Synchronous Debug Monitor 12 programmable 0x0000.0030 Synchronous - 13 - - 98 Reserved July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Table 2-8. Exception Types (continued) Exception Type PendSV SysTick a Vector Number Priority 14 programmable 15 Interrupts Vector Address or b Offset c 0x0000.0038 Asynchronous c 0x0000.003C Asynchronous programmable 16 and above Activation d programmable 0x0000.0040 and above Asynchronous a. 0 is the default priority for all the programmable priorities. b. See “Vector Table” on page 100. c. See SYSPRI1 on page 152. d. See PRIn registers on page 136. Table 2-9. Interrupts Vector Number Interrupt Number (Bit in Interrupt Registers) Vector Address or Offset Description 0-15 - 0x0000.0000 0x0000.003C 16 0 0x0000.0040 GPIO Port A 17 1 0x0000.0044 GPIO Port B 18 2 0x0000.0048 GPIO Port C 19 3 0x0000.004C GPIO Port D 20 4 0x0000.0050 GPIO Port E 21 5 0x0000.0054 UART0 22 6 0x0000.0058 UART1 23 7 0x0000.005C SSI0 24 8 0x0000.0060 I2C0 25-29 9-13 - 30 14 0x0000.0078 ADC0 Sequence 0 31 15 0x0000.007C ADC0 Sequence 1 32 16 0x0000.0080 ADC0 Sequence 2 33 17 0x0000.0084 ADC0 Sequence 3 34 18 0x0000.0088 Watchdog Timers 0 and 1 35 19 0x0000.008C Timer 0A 36 20 0x0000.0090 Timer 0B 37 21 0x0000.0094 Timer 1A 38 22 0x0000.0098 Timer 1B 39 23 0x0000.009C Timer 2A 40 24 0x0000.00A0 Timer 2B 41 25 0x0000.00A4 Analog Comparator 0 42 26 0x0000.00A8 Analog Comparator 1 43 27 0x0000.00AC Analog Comparator 2 44 28 0x0000.00B0 System Control 45 29 0x0000.00B4 Flash Memory Control 46 30 0x0000.00B8 GPIO Port F 47 31 0x0000.00BC GPIO Port G 48 32 0x0000.00C0 GPIO Port H Processor exceptions Reserved July 03, 2014 99 Texas Instruments-Production Data The Cortex-M3 Processor Table 2-9. Interrupts (continued) 2.5.3 Vector Number Interrupt Number (Bit in Interrupt Registers) Vector Address or Offset Description 49 33 0x0000.00C4 UART2 50 34 0x0000.00C8 SSI1 51 35 0x0000.00CC Timer 3A 52 36 0x0000.00D0 Timer 3B 53 37 0x0000.00D4 I2C1 54 38 - 55 39 0x0000.00DC CAN0 56 40 0x0000.00E0 CAN1 57 41 - 58 42 0x0000.00E8 Ethernet Controller 59 43 0x0000.00EC Hibernation Module 60 44 0x0000.00F0 USB 61 45 - Reserved Reserved Reserved 62 46 0x0000.00F8 µDMA Software 63 47 0x0000.00FC µDMA Error 64 48 0x0000.0100 ADC1 Sequence 0 65 49 0x0000.0104 ADC1 Sequence 1 66 50 0x0000.0108 ADC1 Sequence 2 67 51 0x0000.010C ADC1 Sequence 3 68 52 0x0000.0110 I2S0 69 53 0x0000.0114 EPI 70 54 0x0000.0118 GPIO Port J Exception Handlers The processor handles exceptions using: ■ Interrupt Service Routines (ISRs). Interrupts (IRQx) are the exceptions handled by ISRs. ■ Fault Handlers. Hard fault, memory management fault, usage fault, and bus fault are fault exceptions handled by the fault handlers. ■ System Handlers. NMI, PendSV, SVCall, SysTick, and the fault exceptions are all system exceptions that are handled by system handlers. 2.5.4 Vector Table The vector table contains the reset value of the stack pointer and the start addresses, also called exception vectors, for all exception handlers. The vector table is constructed using the vector address or offset shown in Table 2-8 on page 98. Figure 2-6 on page 101 shows the order of the exception vectors in the vector table. The least-significant bit of each vector must be 1, indicating that the exception handler is Thumb code 100 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Figure 2-6. Vector Table Exception number IRQ number 70 54 . . . 18 2 17 1 16 0 15 -1 14 -2 13 Offset 0x0118 . . . 0x004C 0x0048 0x0044 0x0040 0x003C 0x0038 12 11 Vector IRQ54 . . . IRQ2 IRQ1 IRQ0 Systick PendSV Reserved Reserved for Debug -5 10 0x002C 9 SVCall Reserved 8 7 6 -10 5 -11 4 -12 3 -13 2 -14 1 0x0018 0x0014 0x0010 0x000C 0x0008 0x0004 0x0000 Usage fault Bus fault Memory management fault Hard fault NMI Reset Initial SP value On system reset, the vector table is fixed at address 0x0000.0000. Privileged software can write to the Vector Table Offset (VTABLE) register to relocate the vector table start address to a different memory location, in the range 0x0000.0200 to 0x3FFF.FE00 (see “Vector Table” on page 100). Note that when configuring the VTABLE register, the offset must be aligned on a 512-byte boundary. 2.5.5 Exception Priorities As Table 2-8 on page 98 shows, all exceptions have an associated priority, with a lower priority value indicating a higher priority and configurable priorities for all exceptions except Reset, Hard fault, and NMI. If software does not configure any priorities, then all exceptions with a configurable priority have a priority of 0. For information about configuring exception priorities, see page 152 and page 136. Note: Configurable priority values for the Stellaris implementation are in the range 0-7. This means that the Reset, Hard fault, and NMI exceptions, with fixed negative priority values, always have higher priority than any other exception. For example, assigning a higher priority value to IRQ[0] and a lower priority value to IRQ[1] means that IRQ[1] has higher priority than IRQ[0]. If both IRQ[1] and IRQ[0] are asserted, IRQ[1] is processed before IRQ[0]. July 03, 2014 101 Texas Instruments-Production Data The Cortex-M3 Processor If multiple pending exceptions have the same priority, the pending exception with the lowest exception number takes precedence. For example, if both IRQ[0] and IRQ[1] are pending and have the same priority, then IRQ[0] is processed before IRQ[1]. When the processor is executing an exception handler, the exception handler is preempted if a higher priority exception occurs. If an exception occurs with the same priority as the exception being handled, the handler is not preempted, irrespective of the exception number. However, the status of the new interrupt changes to pending. 2.5.6 Interrupt Priority Grouping To increase priority control in systems with interrupts, the NVIC supports priority grouping. This grouping divides each interrupt priority register entry into two fields: ■ An upper field that defines the group priority ■ A lower field that defines a subpriority within the group Only the group priority determines preemption of interrupt exceptions. When the processor is executing an interrupt exception handler, another interrupt with the same group priority as the interrupt being handled does not preempt the handler. If multiple pending interrupts have the same group priority, the subpriority field determines the order in which they are processed. If multiple pending interrupts have the same group priority and subpriority, the interrupt with the lowest IRQ number is processed first. For information about splitting the interrupt priority fields into group priority and subpriority, see page 146. 2.5.7 Exception Entry and Return Descriptions of exception handling use the following terms: ■ Preemption. When the processor is executing an exception handler, an exception can preempt the exception handler if its priority is higher than the priority of the exception being handled. See “Interrupt Priority Grouping” on page 102 for more information about preemption by an interrupt. When one exception preempts another, the exceptions are called nested exceptions. See “Exception Entry” on page 103 more information. ■ Return. Return occurs when the exception handler is completed, and there is no pending exception with sufficient priority to be serviced and the completed exception handler was not handling a late-arriving exception. The processor pops the stack and restores the processor state to the state it had before the interrupt occurred. See “Exception Return” on page 103 for more information. ■ Tail-Chaining. This mechanism speeds up exception servicing. On completion of an exception handler, if there is a pending exception that meets the requirements for exception entry, the stack pop is skipped and control transfers to the new exception handler. ■ Late-Arriving. This mechanism speeds up preemption. If a higher priority exception occurs during state saving for a previous exception, the processor switches to handle the higher priority exception and initiates the vector fetch for that exception. State saving is not affected by late arrival because the state saved is the same for both exceptions. Therefore, the state saving continues uninterrupted. The processor can accept a late arriving exception until the first instruction of the exception handler of the original exception enters the execute stage of the processor. On 102 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller return from the exception handler of the late-arriving exception, the normal tail-chaining rules apply. 2.5.7.1 Exception Entry Exception entry occurs when there is a pending exception with sufficient priority and either the processor is in Thread mode or the new exception is of higher priority than the exception being handled, in which case the new exception preempts the original exception. When one exception preempts another, the exceptions are nested. Sufficient priority means the exception has more priority than any limits set by the mask registers (see PRIMASK on page 83, FAULTMASK on page 84, and BASEPRI on page 85). An exception with less priority than this is pending but is not handled by the processor. When the processor takes an exception, unless the exception is a tail-chained or a late-arriving exception, the processor pushes information onto the current stack. This operation is referred to as stacking and the structure of eight data words is referred to as stack frame. Figure 2-7. Exception Stack Frame ... {aligner} xPSR PC LR R12 R3 R2 R1 R0 Pre-IRQ top of stack IRQ top of stack Immediately after stacking, the stack pointer indicates the lowest address in the stack frame. The stack frame includes the return address, which is the address of the next instruction in the interrupted program. This value is restored to the PC at exception return so that the interrupted program resumes. In parallel to the stacking operation, the processor performs a vector fetch that reads the exception handler start address from the vector table. When stacking is complete, the processor starts executing the exception handler. At the same time, the processor writes an EXC_RETURN value to the LR, indicating which stack pointer corresponds to the stack frame and what operation mode the processor was in before the entry occurred. If no higher-priority exception occurs during exception entry, the processor starts executing the exception handler and automatically changes the status of the corresponding pending interrupt to active. If another higher-priority exception occurs during exception entry, known as late arrival, the processor starts executing the exception handler for this exception and does not change the pending status of the earlier exception. 2.5.7.2 Exception Return Exception return occurs when the processor is in Handler mode and executes one of the following instructions to load the EXC_RETURN value into the PC: ■ An LDM or POP instruction that loads the PC July 03, 2014 103 Texas Instruments-Production Data The Cortex-M3 Processor ■ A BX instruction using any register ■ An LDR instruction with the PC as the destination EXC_RETURN is the value loaded into the LR on exception entry. The exception mechanism relies on this value to detect when the processor has completed an exception handler. The lowest four bits of this value provide information on the return stack and processor mode. Table 2-10 on page 104 shows the EXC_RETURN values with a description of the exception return behavior. EXC_RETURN bits 31:4 are all set. When this value is loaded into the PC, it indicates to the processor that the exception is complete, and the processor initiates the appropriate exception return sequence. Table 2-10. Exception Return Behavior EXC_RETURN[31:0] Description 0xFFFF.FFF0 Reserved 0xFFFF.FFF1 Return to Handler mode. Exception return uses state from MSP. Execution uses MSP after return. 0xFFFF.FFF2 - 0xFFFF.FFF8 Reserved 0xFFFF.FFF9 Return to Thread mode. Exception return uses state from MSP. Execution uses MSP after return. 0xFFFF.FFFA - 0xFFFF.FFFC Reserved 0xFFFF.FFFD Return to Thread mode. Exception return uses state from PSP. Execution uses PSP after return. 0xFFFF.FFFE - 0xFFFF.FFFF 2.6 Reserved Fault Handling Faults are a subset of the exceptions (see “Exception Model” on page 96). The following conditions generate a fault: ■ A bus error on an instruction fetch or vector table load or a data access. ■ An internally detected error such as an undefined instruction or an attempt to change state with a BX instruction. ■ Attempting to execute an instruction from a memory region marked as Non-Executable (XN). ■ An MPU fault because of a privilege violation or an attempt to access an unmanaged region. 2.6.1 Fault Types Table 2-11 on page 104 shows the types of fault, the handler used for the fault, the corresponding fault status register, and the register bit that indicates the fault has occurred. See page 159 for more information about the fault status registers. Table 2-11. Faults Fault Handler Fault Status Register Bit Name Bus error on a vector read Hard fault Hard Fault Status (HFAULTSTAT) VECT 104 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Table 2-11. Faults (continued) Fault Handler Fault Status Register Bit Name Fault escalated to a hard fault Hard fault Hard Fault Status (HFAULTSTAT) FORCED MPU or default memory mismatch on Memory management instruction access fault Memory Management Fault Status (MFAULTSTAT) IERR MPU or default memory mismatch on Memory management data access fault Memory Management Fault Status (MFAULTSTAT) DERR MPU or default memory mismatch on Memory management exception stacking fault Memory Management Fault Status (MFAULTSTAT) MSTKE MPU or default memory mismatch on Memory management exception unstacking fault Memory Management Fault Status (MFAULTSTAT) MUSTKE Bus error during exception stacking a Bus fault Bus Fault Status (BFAULTSTAT) BSTKE Bus error during exception unstacking Bus fault Bus Fault Status (BFAULTSTAT) BUSTKE Bus error during instruction prefetch Bus fault Bus Fault Status (BFAULTSTAT) IBUS Precise data bus error Bus fault Bus Fault Status (BFAULTSTAT) PRECISE Imprecise data bus error Bus fault Bus Fault Status (BFAULTSTAT) IMPRE Attempt to access a coprocessor Usage fault Usage Fault Status (UFAULTSTAT) NOCP Undefined instruction Usage fault Usage Fault Status (UFAULTSTAT) UNDEF Attempt to enter an invalid instruction Usage fault b set state Usage Fault Status (UFAULTSTAT) INVSTAT Invalid EXC_RETURN value Usage fault Usage Fault Status (UFAULTSTAT) INVPC Illegal unaligned load or store Usage fault Usage Fault Status (UFAULTSTAT) UNALIGN Divide by 0 Usage fault Usage Fault Status (UFAULTSTAT) DIV0 a. Occurs on an access to an XN region even if the MPU is disabled. b. Attempting to use an instruction set other than the Thumb instruction set, or returning to a non load-store-multiple instruction with ICI continuation. 2.6.2 Fault Escalation and Hard Faults All fault exceptions except for hard fault have configurable exception priority (see SYSPRI1 on page 152). Software can disable execution of the handlers for these faults (see SYSHNDCTRL on page 155). Usually, the exception priority, together with the values of the exception mask registers, determines whether the processor enters the fault handler, and whether a fault handler can preempt another fault handler as described in “Exception Model” on page 96. In some situations, a fault with configurable priority is treated as a hard fault. This process is called priority escalation, and the fault is described as escalated to hard fault. Escalation to hard fault occurs when: ■ A fault handler causes the same kind of fault as the one it is servicing. This escalation to hard fault occurs because a fault handler cannot preempt itself because it must have the same priority as the current priority level. ■ A fault handler causes a fault with the same or lower priority as the fault it is servicing. This situation happens because the handler for the new fault cannot preempt the currently executing fault handler. ■ An exception handler causes a fault for which the priority is the same as or lower than the currently executing exception. July 03, 2014 105 Texas Instruments-Production Data The Cortex-M3 Processor ■ A fault occurs and the handler for that fault is not enabled. If a bus fault occurs during a stack push when entering a bus fault handler, the bus fault does not escalate to a hard fault. Thus if a corrupted stack causes a fault, the fault handler executes even though the stack push for the handler failed. The fault handler operates but the stack contents are corrupted. Note: 2.6.3 Only Reset and NMI can preempt the fixed priority hard fault. A hard fault can preempt any exception other than Reset, NMI, or another hard fault. Fault Status Registers and Fault Address Registers The fault status registers indicate the cause of a fault. For bus faults and memory management faults, the fault address register indicates the address accessed by the operation that caused the fault, as shown in Table 2-12 on page 106. Table 2-12. Fault Status and Fault Address Registers 2.6.4 Handler Status Register Name Address Register Name Register Description Hard fault Hard Fault Status (HFAULTSTAT) - page 165 Memory management Memory Management Fault Status fault (MFAULTSTAT) Memory Management Fault Address (MMADDR) page 159 Bus fault Bus Fault Status (BFAULTSTAT) Bus Fault Address (FAULTADDR) page 159 Usage fault Usage Fault Status (UFAULTSTAT) - page 159 page 166 page 167 Lockup The processor enters a lockup state if a hard fault occurs when executing the NMI or hard fault handlers. When the processor is in the lockup state, it does not execute any instructions. The processor remains in lockup state until it is reset, an NMI occurs, or it is halted by a debugger. Note: 2.7 If the lockup state occurs from the NMI handler, a subsequent NMI does not cause the processor to leave the lockup state. Power Management The Cortex-M3 processor sleep modes reduce power consumption: ■ Sleep mode stops the processor clock. ■ Deep-sleep mode stops the system clock and switches off the PLL and Flash memory. The SLEEPDEEP bit of the System Control (SYSCTRL) register selects which sleep mode is used (see page 148). For more information about the behavior of the sleep modes, see “System Control” on page 203. This section describes the mechanisms for entering sleep mode and the conditions for waking up from sleep mode, both of which apply to Sleep mode and Deep-sleep mode. 2.7.1 Entering Sleep Modes This section describes the mechanisms software can use to put the processor into one of the sleep modes. 106 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller The system can generate spurious wake-up events, for example a debug operation wakes up the processor. Therefore, software must be able to put the processor back into sleep mode after such an event. A program might have an idle loop to put the processor back to sleep mode. 2.7.1.1 Wait for Interrupt The wait for interrupt instruction, WFI, causes immediate entry to sleep mode unless the wake-up condition is true (see “Wake Up from WFI or Sleep-on-Exit” on page 107). When the processor executes a WFI instruction, it stops executing instructions and enters sleep mode. See the Cortex™-M3/M4 Instruction Set Technical User's Manual for more information. 2.7.1.2 Wait for Event The wait for event instruction, WFE, causes entry to sleep mode conditional on the value of a one-bit event register. When the processor executes a WFE instruction, it checks the event register. If the register is 0, the processor stops executing instructions and enters sleep mode. If the register is 1, the processor clears the register and continues executing instructions without entering sleep mode. If the event register is 1, the processor must not enter sleep mode on execution of a WFE instruction. Typically, this situation occurs if an SEV instruction has been executed. Software cannot access this register directly. See the Cortex™-M3/M4 Instruction Set Technical User's Manual for more information. 2.7.1.3 Sleep-on-Exit If the SLEEPEXIT bit of the SYSCTRL register is set, when the processor completes the execution of all exception handlers, it returns to Thread mode and immediately enters sleep mode. This mechanism can be used in applications that only require the processor to run when an exception occurs. 2.7.2 Wake Up from Sleep Mode The conditions for the processor to wake up depend on the mechanism that cause it to enter sleep mode. 2.7.2.1 Wake Up from WFI or Sleep-on-Exit Normally, the processor wakes up only when the NVIC detects an exception with sufficient priority to cause exception entry. Some embedded systems might have to execute system restore tasks after the processor wakes up and before executing an interrupt handler. Entry to the interrupt handler can be delayed by setting the PRIMASK bit and clearing the FAULTMASK bit. If an interrupt arrives that is enabled and has a higher priority than current exception priority, the processor wakes up but does not execute the interrupt handler until the processor clears PRIMASK. For more information about PRIMASK and FAULTMASK, see page 83 and page 84. 2.7.2.2 Wake Up from WFE The processor wakes up if it detects an exception with sufficient priority to cause exception entry. In addition, if the SEVONPEND bit in the SYSCTRL register is set, any new pending interrupt triggers an event and wakes up the processor, even if the interrupt is disabled or has insufficient priority to cause exception entry. For more information about SYSCTRL, see page 148. July 03, 2014 107 Texas Instruments-Production Data The Cortex-M3 Processor 2.8 Instruction Set Summary The processor implements a version of the Thumb instruction set. Table 2-13 on page 108 lists the supported instructions. Note: In Table 2-13 on page 108: ■ ■ ■ ■ ■ Angle brackets, <>, enclose alternative forms of the operand Braces, {}, enclose optional operands The Operands column is not exhaustive Op2 is a flexible second operand that can be either a register or a constant Most instructions can use an optional condition code suffix For more information on the instructions and operands, see the instruction descriptions in the Cortex™-M3/M4 Instruction Set Technical User's Manual. Table 2-13. Cortex-M3 Instruction Summary Mnemonic Operands Brief Description Flags ADC, ADCS {Rd,} Rn, Op2 Add with carry N,Z,C,V ADD, ADDS {Rd,} Rn, Op2 Add N,Z,C,V ADD, ADDW {Rd,} Rn , #imm12 Add N,Z,C,V ADR Rd, label Load PC-relative address - AND, ANDS {Rd,} Rn, Op2 Logical AND N,Z,C ASR, ASRS Rd, Rm, <Rs|#n> Arithmetic shift right N,Z,C B label Branch - BFC Rd, #lsb, #width Bit field clear - BFI Rd, Rn, #lsb, #width Bit field insert - BIC, BICS {Rd,} Rn, Op2 Bit clear N,Z,C BKPT #imm Breakpoint - BL label Branch with link - BLX Rm Branch indirect with link - BX Rm Branch indirect - CBNZ Rn, label Compare and branch if non-zero - CBZ Rn, label Compare and branch if zero - CLREX - Clear exclusive - CLZ Rd, Rm Count leading zeros - CMN Rn, Op2 Compare negative N,Z,C,V CMP Rn, Op2 Compare N,Z,C,V CPSID i Change processor state, disable interrupts - CPSIE i Change processor state, enable interrupts - DMB - Data memory barrier - DSB - Data synchronization barrier - EOR, EORS {Rd,} Rn, Op2 Exclusive OR N,Z,C ISB - Instruction synchronization barrier - IT - If-Then condition block - 108 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Table 2-13. Cortex-M3 Instruction Summary (continued) Mnemonic Operands Brief Description LDM Rn{!}, reglist Load multiple registers, increment after - LDMDB, LDMEA Rn{!}, reglist Load multiple registers, decrement before LDMFD, LDMIA Rn{!}, reglist Load multiple registers, increment after - LDR Rt, [Rn, #offset] Load register with word - LDRB, LDRBT Rt, [Rn, #offset] Load register with byte - LDRD Rt, Rt2, [Rn, #offset] Load register with two bytes - LDREX Rt, [Rn, #offset] Load register exclusive - LDREXB Rt, [Rn] Load register exclusive with byte - LDREXH Rt, [Rn] Load register exclusive with halfword - LDRH, LDRHT Rt, [Rn, #offset] Load register with halfword - LDRSB, LDRSBT Rt, [Rn, #offset] Load register with signed byte - LDRSH, LDRSHT Rt, [Rn, #offset] Load register with signed halfword - LDRT Rt, [Rn, #offset] Load register with word - LSL, LSLS Rd, Rm, <Rs|#n> Logical shift left N,Z,C LSR, LSRS Rd, Rm, <Rs|#n> Logical shift right N,Z,C MLA Rd, Rn, Rm, Ra Multiply with accumulate, 32-bit result - MLS Rd, Rn, Rm, Ra Multiply and subtract, 32-bit result - MOV, MOVS Rd, Op2 Move N,Z,C MOV, MOVW Rd, #imm16 Move 16-bit constant N,Z,C MOVT Rd, #imm16 Move top - MRS Rd, spec_reg Move from special register to general register - MSR spec_reg, Rm Move from general register to special register N,Z,C,V MUL, MULS {Rd,} Rn, Rm Multiply, 32-bit result N,Z MVN, MVNS Rd, Op2 Move NOT N,Z,C NOP - No operation - ORN, ORNS {Rd,} Rn, Op2 Logical OR NOT N,Z,C ORR, ORRS {Rd,} Rn, Op2 Logical OR N,Z,C POP reglist Pop registers from stack - PUSH reglist Push registers onto stack - RBIT Rd, Rn Reverse bits - REV Rd, Rn Reverse byte order in a word - REV16 Rd, Rn Reverse byte order in each halfword - REVSH Rd, Rn Reverse byte order in bottom halfword and sign extend - ROR, RORS Rd, Rm, <Rs|#n> Rotate right N,Z,C RRX, RRXS Rd, Rm Rotate right with extend N,Z,C RSB, RSBS {Rd,} Rn, Op2 Reverse subtract N,Z,C,V SBC, SBCS {Rd,} Rn, Op2 Subtract with carry N,Z,C,V SBFX Rd, Rn, #lsb, #width Signed bit field extract - July 03, 2014 Flags - 109 Texas Instruments-Production Data The Cortex-M3 Processor Table 2-13. Cortex-M3 Instruction Summary (continued) Mnemonic Operands Brief Description Flags SDIV {Rd,} Rn, Rm Signed divide - SEV - Send event - SMLAL RdLo, RdHi, Rn, Rm Signed multiply with accumulate (32x32+64), 64-bit result - SMULL RdLo, RdHi, Rn, Rm Signed multiply (32x32), 64-bit result - SSAT Rd, #n, Rm {,shift #s} Signed saturate Q STM Rn{!}, reglist Store multiple registers, increment after - STMDB, STMEA Rn{!}, reglist Store multiple registers, decrement before STMFD, STMIA Rn{!}, reglist Store multiple registers, increment after - STR Rt, [Rn {, #offset}] Store register word - STRB, STRBT Rt, [Rn {, #offset}] Store register byte - STRD Rt, Rt2, [Rn {, #offset}] Store register two words - STREX Rt, Rt, [Rn {, #offset}] Store register exclusive - STREXB Rd, Rt, [Rn] Store register exclusive byte - STREXH Rd, Rt, [Rn] Store register exclusive halfword - STRH, STRHT Rt, [Rn {, #offset}] Store register halfword - STRSB, STRSBT Rt, [Rn {, #offset}] Store register signed byte - STRSH, STRSHT Rt, [Rn {, #offset}] Store register signed halfword - STRT Rt, [Rn {, #offset}] Store register word - SUB, SUBS {Rd,} Rn, Op2 Subtract N,Z,C,V SUB, SUBW {Rd,} Rn, #imm12 Subtract 12-bit constant N,Z,C,V SVC #imm Supervisor call - SXTB {Rd,} Rm {,ROR #n} Sign extend a byte - SXTH {Rd,} Rm {,ROR #n} Sign extend a halfword - TBB [Rn, Rm] Table branch byte - TBH [Rn, Rm, LSL #1] Table branch halfword - TEQ Rn, Op2 Test equivalence N,Z,C TST Rn, Op2 Test N,Z,C UBFX Rd, Rn, #lsb, #width Unsigned bit field extract - UDIV {Rd,} Rn, Rm Unsigned divide - UMLAL RdLo, RdHi, Rn, Rm Unsigned multiply with accumulate (32x32+32+32), 64-bit result - UMULL RdLo, RdHi, Rn, Rm Unsigned multiply (32x 2), 64-bit result - USAT Rd, #n, Rm {,shift #s} Unsigned Saturate Q UXTB {Rd,} Rm, {,ROR #n} Zero extend a Byte - UXTH {Rd,} Rm, {,ROR #n} Zero extend a Halfword - WFE - Wait for event - WFI - Wait for interrupt - 110 - July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller 3 Cortex-M3 Peripherals ® This chapter provides information on the Stellaris implementation of the Cortex-M3 processor peripherals, including: ■ SysTick (see page 111) Provides a simple, 24-bit clear-on-write, decrementing, wrap-on-zero counter with a flexible control mechanism. ■ Nested Vectored Interrupt Controller (NVIC) (see page 112) – Facilitates low-latency exception and interrupt handling – Controls power management – Implements system control registers ■ System Control Block (SCB) (see page 114) Provides system implementation information and system control, including configuration, control, and reporting of system exceptions. ■ Memory Protection Unit (MPU) (see page 114) Supports the standard ARMv7 Protected Memory System Architecture (PMSA) model. The MPU provides full support for protection regions, overlapping protection regions, access permissions, and exporting memory attributes to the system. Table 3-1 on page 111 shows the address map of the Private Peripheral Bus (PPB). Some peripheral register regions are split into two address regions, as indicated by two addresses listed. Table 3-1. Core Peripheral Register Regions Address Core Peripheral Description (see page ...) 0xE000.E010-0xE000.E01F System Timer 111 0xE000.E100-0xE000.E4EF Nested Vectored Interrupt Controller 112 System Control Block 114 Memory Protection Unit 114 0xE000.EF00-0xE000.EF03 0xE000.E008-0xE000.E00F 0xE000.ED00-0xE000.ED3F 0xE000.ED90-0xE000.EDB8 3.1 Functional Description This chapter provides information on the Stellaris implementation of the Cortex-M3 processor peripherals: SysTick, NVIC, SCB and MPU. 3.1.1 System Timer (SysTick) Cortex-M3 includes an integrated system timer, SysTick, which provides a simple, 24-bit clear-on-write, decrementing, wrap-on-zero counter with a flexible control mechanism. The counter can be used in several different ways, for example as: ■ An RTOS tick timer that fires at a programmable rate (for example, 100 Hz) and invokes a SysTick routine. ■ A high-speed alarm timer using the system clock. July 03, 2014 111 Texas Instruments-Production Data Cortex-M3 Peripherals ■ A variable rate alarm or signal timer—the duration is range-dependent on the reference clock used and the dynamic range of the counter. ■ A simple counter used to measure time to completion and time used. ■ An internal clock source control based on missing/meeting durations. The COUNT bit in the STCTRL control and status register can be used to determine if an action completed within a set duration, as part of a dynamic clock management control loop. The timer consists of three registers: ■ SysTick Control and Status (STCTRL): A control and status counter to configure its clock, enable the counter, enable the SysTick interrupt, and determine counter status. ■ SysTick Reload Value (STRELOAD): The reload value for the counter, used to provide the counter's wrap value. ■ SysTick Current Value (STCURRENT): The current value of the counter. When enabled, the timer counts down on each clock from the reload value to zero, reloads (wraps) to the value in the STRELOAD register on the next clock edge, then decrements on subsequent clocks. Clearing the STRELOAD register disables the counter on the next wrap. When the counter reaches zero, the COUNT status bit is set. The COUNT bit clears on reads. Writing to the STCURRENT register clears the register and the COUNT status bit. The write does not trigger the SysTick exception logic. On a read, the current value is the value of the register at the time the register is accessed. The SysTick counter runs on the system clock. If this clock signal is stopped for low power mode, the SysTick counter stops. Ensure software uses aligned word accesses to access the SysTick registers. Note: 3.1.2 When the processor is halted for debugging, the counter does not decrement. Nested Vectored Interrupt Controller (NVIC) This section describes the Nested Vectored Interrupt Controller (NVIC) and the registers it uses. The NVIC supports: ■ 47 interrupts. ■ A programmable priority level of 0-7 for each interrupt. A higher level corresponds to a lower priority, so level 0 is the highest interrupt priority. ■ Low-latency exception and interrupt handling. ■ Level and pulse detection of interrupt signals. ■ Dynamic reprioritization of interrupts. ■ Grouping of priority values into group priority and subpriority fields. ■ Interrupt tail-chaining. ■ An external Non-maskable interrupt (NMI). 112 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller The processor automatically stacks its state on exception entry and unstacks this state on exception exit, with no instruction overhead, providing low latency exception handling. 3.1.2.1 Level-Sensitive and Pulse Interrupts The processor supports both level-sensitive and pulse interrupts. Pulse interrupts are also described as edge-triggered interrupts. A level-sensitive interrupt is held asserted until the peripheral deasserts the interrupt signal. Typically this happens because the ISR accesses the peripheral, causing it to clear the interrupt request. A pulse interrupt is an interrupt signal sampled synchronously on the rising edge of the processor clock. To ensure the NVIC detects the interrupt, the peripheral must assert the interrupt signal for at least one clock cycle, during which the NVIC detects the pulse and latches the interrupt. When the processor enters the ISR, it automatically removes the pending state from the interrupt (see “Hardware and Software Control of Interrupts” on page 113 for more information). For a level-sensitive interrupt, if the signal is not deasserted before the processor returns from the ISR, the interrupt becomes pending again, and the processor must execute its ISR again. As a result, the peripheral can hold the interrupt signal asserted until it no longer needs servicing. 3.1.2.2 Hardware and Software Control of Interrupts The Cortex-M3 latches all interrupts. A peripheral interrupt becomes pending for one of the following reasons: ■ The NVIC detects that the interrupt signal is High and the interrupt is not active. ■ The NVIC detects a rising edge on the interrupt signal. ■ Software writes to the corresponding interrupt set-pending register bit, or to the Software Trigger Interrupt (SWTRIG) register to make a Software-Generated Interrupt pending. See the INT bit in the PEND0 register on page 130 or SWTRIG on page 138. A pending interrupt remains pending until one of the following: ■ The processor enters the ISR for the interrupt, changing the state of the interrupt from pending to active. Then: – For a level-sensitive interrupt, when the processor returns from the ISR, the NVIC samples the interrupt signal. If the signal is asserted, the state of the interrupt changes to pending, which might cause the processor to immediately re-enter the ISR. Otherwise, the state of the interrupt changes to inactive. – For a pulse interrupt, the NVIC continues to monitor the interrupt signal, and if this is pulsed the state of the interrupt changes to pending and active. In this case, when the processor returns from the ISR the state of the interrupt changes to pending, which might cause the processor to immediately re-enter the ISR. If the interrupt signal is not pulsed while the processor is in the ISR, when the processor returns from the ISR the state of the interrupt changes to inactive. ■ Software writes to the corresponding interrupt clear-pending register bit – For a level-sensitive interrupt, if the interrupt signal is still asserted, the state of the interrupt does not change. Otherwise, the state of the interrupt changes to inactive. July 03, 2014 113 Texas Instruments-Production Data Cortex-M3 Peripherals – For a pulse interrupt, the state of the interrupt changes to inactive, if the state was pending or to active, if the state was active and pending. 3.1.3 System Control Block (SCB) The System Control Block (SCB) provides system implementation information and system control, including configuration, control, and reporting of the system exceptions. 3.1.4 Memory Protection Unit (MPU) This section describes the Memory protection unit (MPU). The MPU divides the memory map into a number of regions and defines the location, size, access permissions, and memory attributes of each region. The MPU supports independent attribute settings for each region, overlapping regions, and export of memory attributes to the system. The memory attributes affect the behavior of memory accesses to the region. The Cortex-M3 MPU defines eight separate memory regions, 0-7, and a background region. When memory regions overlap, a memory access is affected by the attributes of the region with the highest number. For example, the attributes for region 7 take precedence over the attributes of any region that overlaps region 7. The background region has the same memory access attributes as the default memory map, but is accessible from privileged software only. The Cortex-M3 MPU memory map is unified, meaning that instruction accesses and data accesses have the same region settings. If a program accesses a memory location that is prohibited by the MPU, the processor generates a memory management fault, causing a fault exception and possibly causing termination of the process in an OS environment. In an OS environment, the kernel can update the MPU region setting dynamically based on the process to be executed. Typically, an embedded OS uses the MPU for memory protection. Configuration of MPU regions is based on memory types (see “Memory Regions, Types and Attributes” on page 89 for more information). Table 3-2 on page 114 shows the possible MPU region attributes. See the section called “MPU Configuration for a Stellaris Microcontroller” on page 118 for guidelines for programming a microcontroller implementation. Table 3-2. Memory Attributes Summary Memory Type Description Strongly Ordered All accesses to Strongly Ordered memory occur in program order. Device Memory-mapped peripherals Normal Normal memory To avoid unexpected behavior, disable the interrupts before updating the attributes of a region that the interrupt handlers might access. Ensure software uses aligned accesses of the correct size to access MPU registers: ■ Except for the MPU Region Attribute and Size (MPUATTR) register, all MPU registers must be accessed with aligned word accesses. ■ The MPUATTR register can be accessed with byte or aligned halfword or word accesses. 114 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller The processor does not support unaligned accesses to MPU registers. When setting up the MPU, and if the MPU has previously been programmed, disable unused regions to prevent any previous region settings from affecting the new MPU setup. 3.1.4.1 Updating an MPU Region To update the attributes for an MPU region, the MPU Region Number (MPUNUMBER), MPU Region Base Address (MPUBASE) and MPUATTR registers must be updated. Each register can be programmed separately or with a multiple-word write to program all of these registers. You can use the MPUBASEx and MPUATTRx aliases to program up to four regions simultaneously using an STM instruction. Updating an MPU Region Using Separate Words This example simple code configures one region: ; R1 = region number ; R2 = size/enable ; R3 = attributes ; R4 = address LDR R0,=MPUNUMBER STR R1, [R0, #0x0] STR R4, [R0, #0x4] STRH R2, [R0, #0x8] STRH R3, [R0, #0xA] ; ; ; ; ; 0xE000ED98, MPU region number register Region Number Region Base Address Region Size and Enable Region Attribute Disable a region before writing new region settings to the MPU if you have previously enabled the region being changed. For example: ; R1 = region number ; R2 = size/enable ; R3 = attributes ; R4 = address LDR R0,=MPUNUMBER STR R1, [R0, #0x0] BIC R2, R2, #1 STRH R2, [R0, #0x8] STR R4, [R0, #0x4] STRH R3, [R0, #0xA] ORR R2, #1 STRH R2, [R0, #0x8] ; ; ; ; ; ; ; ; 0xE000ED98, MPU region number register Region Number Disable Region Size and Enable Region Base Address Region Attribute Enable Region Size and Enable Software must use memory barrier instructions: ■ Before MPU setup, if there might be outstanding memory transfers, such as buffered writes, that might be affected by the change in MPU settings. ■ After MPU setup, if it includes memory transfers that must use the new MPU settings. However, memory barrier instructions are not required if the MPU setup process starts by entering an exception handler, or is followed by an exception return, because the exception entry and exception return mechanism cause memory barrier behavior. Software does not need any memory barrier instructions during MPU setup, because it accesses the MPU through the Private Peripheral Bus (PPB), which is a Strongly Ordered memory region. July 03, 2014 115 Texas Instruments-Production Data Cortex-M3 Peripherals For example, if all of the memory access behavior is intended to take effect immediately after the programming sequence, then a DSB instruction and an ISB instruction should be used. A DSB is required after changing MPU settings, such as at the end of context switch. An ISB is required if the code that programs the MPU region or regions is entered using a branch or call. If the programming sequence is entered using a return from exception, or by taking an exception, then an ISB is not required. Updating an MPU Region Using Multi-Word Writes The MPU can be programmed directly using multi-word writes, depending how the information is divided. Consider the following reprogramming: ; R1 = region number ; R2 = address ; R3 = size, attributes in one LDR R0, =MPUNUMBER ; 0xE000ED98, MPU region number register STR R1, [R0, #0x0] ; Region Number STR R2, [R0, #0x4] ; Region Base Address STR R3, [R0, #0x8] ; Region Attribute, Size and Enable An STM instruction can be used to optimize this: ; R1 = region number ; R2 = address ; R3 = size, attributes in one LDR R0, =MPUNUMBER ; 0xE000ED98, MPU region number register STM R0, {R1-R3} ; Region number, address, attribute, size and enable This operation can be done in two words for pre-packed information, meaning that the MPU Region Base Address (MPUBASE) register (see page 172) contains the required region number and has the VALID bit set. This method can be used when the data is statically packed, for example in a boot loader: ; R1 = address and region number in one ; R2 = size and attributes in one LDR R0, =MPUBASE ; 0xE000ED9C, MPU Region Base register STR R1, [R0, #0x0] ; Region base address and region number combined ; with VALID (bit 4) set STR R2, [R0, #0x4] ; Region Attribute, Size and Enable Subregions Regions of 256 bytes or more are divided into eight equal-sized subregions. Set the corresponding bit in the SRD field of the MPU Region Attribute and Size (MPUATTR) register (see page 174) to disable a subregion. The least-significant bit of the SRD field controls the first subregion, and the most-significant bit controls the last subregion. Disabling a subregion means another region overlapping the disabled range matches instead. If no other enabled region overlaps the disabled subregion, the MPU issues a fault. Regions of 32, 64, and 128 bytes do not support subregions. With regions of these sizes, the SRD field must be configured to 0x00, otherwise the MPU behavior is unpredictable. 116 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Example of SRD Use Two regions with the same base address overlap. Region one is 128 KB, and region two is 512 KB. To ensure the attributes from region one apply to the first 128 KB region, configure the SRD field for region two to 0x03 to disable the first two subregions, as Figure 3-1 on page 117 shows. Figure 3-1. SRD Use Example Region 2, with subregions Region 1 Base address of both regions 3.1.4.2 Offset from base address 512KB 448KB 384KB 320KB 256KB 192KB 128KB Disabled subregion 64KB Disabled subregion 0 MPU Access Permission Attributes The access permission bits, TEX, S, C, B, AP, and XN of the MPUATTR register, control access to the corresponding memory region. If an access is made to an area of memory without the required permissions, then the MPU generates a permission fault. Table 3-3 on page 117 shows the encodings for the TEX, C, B, and S access permission bits. All encodings are shown for completeness, however the current implementation of the Cortex-M3 does not support the concept of cacheability or shareability. Refer to the section called “MPU Configuration for a Stellaris Microcontroller” on page 118 for information on programming the MPU for Stellaris implementations. Table 3-3. TEX, S, C, and B Bit Field Encoding TEX S 000b x C B Memory Type Shareability Other Attributes a 0 0 Strongly Ordered Shareable - a - 000 x 0 1 Device Shareable 000 0 1 0 Normal Not shareable 000 1 1 0 Normal Shareable 000 0 1 1 Normal Not shareable 000 1 1 1 Normal Shareable 001 0 0 0 Normal Not shareable 001 1 0 0 Normal Shareable Outer and inner noncacheable. 001 x a 0 1 Reserved encoding - - a Outer and inner write-through. No write allocate. 001 x 1 0 Reserved encoding - - 001 0 1 1 Normal Not shareable 001 1 1 1 Normal Shareable Outer and inner write-back. Write and read allocate. 010 x a 0 0 Device Not shareable Nonshared Device. a 0 1 Reserved encoding - - a 1 x Reserved encoding - - 010 x 010 x a July 03, 2014 117 Texas Instruments-Production Data Cortex-M3 Peripherals Table 3-3. TEX, S, C, and B Bit Field Encoding (continued) TEX S C B Memory Type Shareability Other Attributes 1BB 0 A A Normal Not shareable 1BB 1 A A Normal Shareable Cached memory (BB = outer policy, AA = inner policy). See Table 3-4 for the encoding of the AA and BB bits. a. The MPU ignores the value of this bit. Table 3-4 on page 118 shows the cache policy for memory attribute encodings with a TEX value in the range of 0x4-0x7. Table 3-4. Cache Policy for Memory Attribute Encoding Encoding, AA or BB Corresponding Cache Policy 00 Non-cacheable 01 Write back, write and read allocate 10 Write through, no write allocate 11 Write back, no write allocate Table 3-5 on page 118 shows the AP encodings in the MPUATTR register that define the access permissions for privileged and unprivileged software. Table 3-5. AP Bit Field Encoding AP Bit Field Privileged Permissions Unprivileged Permissions Description 000 No access No access All accesses generate a permission fault. 001 R/W No access Access from privileged software only. 010 R/W RO Writes by unprivileged software generate a permission fault. 011 R/W R/W Full access. 100 Unpredictable Unpredictable Reserved. 101 RO No access Reads by privileged software only. 110 RO RO Read-only, by privileged or unprivileged software. 111 RO RO Read-only, by privileged or unprivileged software. MPU Configuration for a Stellaris Microcontroller Stellaris microcontrollers have only a single processor and no caches. As a result, the MPU should be programmed as shown in Table 3-6 on page 118. Table 3-6. Memory Region Attributes for Stellaris Microcontrollers Memory Region TEX S C B Memory Type and Attributes Flash memory 000b 0 1 0 Normal memory, non-shareable, write-through Internal SRAM 000b 1 1 0 Normal memory, shareable, write-through External SRAM 000b 1 1 1 Normal memory, shareable, write-back, write-allocate Peripherals 000b 1 0 1 Device memory, shareable 118 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller In current Stellaris microcontroller implementations, the shareability and cache policy attributes do not affect the system behavior. However, using these settings for the MPU regions can make the application code more portable. The values given are for typical situations. 3.1.4.3 MPU Mismatch When an access violates the MPU permissions, the processor generates a memory management fault (see “Exceptions and Interrupts” on page 87 for more information). The MFAULTSTAT register indicates the cause of the fault. See page 159 for more information. 3.2 Register Map Table 3-7 on page 119 lists the Cortex-M3 Peripheral SysTick, NVIC, MPU and SCB registers. The offset listed is a hexadecimal increment to the register's address, relative to the Core Peripherals base address of 0xE000.E000. Note: Register spaces that are not used are reserved for future or internal use. Software should not modify any reserved memory address. Table 3-7. Peripherals Register Map Offset Name Type Reset Description See page System Timer (SysTick) Registers 0x010 STCTRL R/W 0x0000.0004 SysTick Control and Status Register 122 0x014 STRELOAD R/W 0x0000.0000 SysTick Reload Value Register 124 0x018 STCURRENT R/WC 0x0000.0000 SysTick Current Value Register 125 Nested Vectored Interrupt Controller (NVIC) Registers 0x100 EN0 R/W 0x0000.0000 Interrupt 0-31 Set Enable 126 0x104 EN1 R/W 0x0000.0000 Interrupt 32-54 Set Enable 127 0x180 DIS0 R/W 0x0000.0000 Interrupt 0-31 Clear Enable 128 0x184 DIS1 R/W 0x0000.0000 Interrupt 32-54 Clear Enable 129 0x200 PEND0 R/W 0x0000.0000 Interrupt 0-31 Set Pending 130 0x204 PEND1 R/W 0x0000.0000 Interrupt 32-54 Set Pending 131 0x280 UNPEND0 R/W 0x0000.0000 Interrupt 0-31 Clear Pending 132 0x284 UNPEND1 R/W 0x0000.0000 Interrupt 32-54 Clear Pending 133 0x300 ACTIVE0 RO 0x0000.0000 Interrupt 0-31 Active Bit 134 0x304 ACTIVE1 RO 0x0000.0000 Interrupt 32-54 Active Bit 135 0x400 PRI0 R/W 0x0000.0000 Interrupt 0-3 Priority 136 0x404 PRI1 R/W 0x0000.0000 Interrupt 4-7 Priority 136 0x408 PRI2 R/W 0x0000.0000 Interrupt 8-11 Priority 136 0x40C PRI3 R/W 0x0000.0000 Interrupt 12-15 Priority 136 0x410 PRI4 R/W 0x0000.0000 Interrupt 16-19 Priority 136 July 03, 2014 119 Texas Instruments-Production Data Cortex-M3 Peripherals Table 3-7. Peripherals Register Map (continued) Description See page Offset Name Type Reset 0x414 PRI5 R/W 0x0000.0000 Interrupt 20-23 Priority 136 0x418 PRI6 R/W 0x0000.0000 Interrupt 24-27 Priority 136 0x41C PRI7 R/W 0x0000.0000 Interrupt 28-31 Priority 136 0x420 PRI8 R/W 0x0000.0000 Interrupt 32-35 Priority 136 0x424 PRI9 R/W 0x0000.0000 Interrupt 36-39 Priority 136 0x428 PRI10 R/W 0x0000.0000 Interrupt 40-43 Priority 136 0x42C PRI11 R/W 0x0000.0000 Interrupt 44-47 Priority 136 0x430 PRI12 R/W 0x0000.0000 Interrupt 48-51 Priority 136 0x434 PRI13 R/W 0x0000.0000 Interrupt 52-54 Priority 136 0xF00 SWTRIG WO 0x0000.0000 Software Trigger Interrupt 138 System Control Block (SCB) Registers 0x008 ACTLR R/W 0x0000.0000 Auxiliary Control 139 0xD00 CPUID RO 0x412F.C230 CPU ID Base 141 0xD04 INTCTRL R/W 0x0000.0000 Interrupt Control and State 142 0xD08 VTABLE R/W 0x0000.0000 Vector Table Offset 145 0xD0C APINT R/W 0xFA05.0000 Application Interrupt and Reset Control 146 0xD10 SYSCTRL R/W 0x0000.0000 System Control 148 0xD14 CFGCTRL R/W 0x0000.0200 Configuration and Control 150 0xD18 SYSPRI1 R/W 0x0000.0000 System Handler Priority 1 152 0xD1C SYSPRI2 R/W 0x0000.0000 System Handler Priority 2 153 0xD20 SYSPRI3 R/W 0x0000.0000 System Handler Priority 3 154 0xD24 SYSHNDCTRL R/W 0x0000.0000 System Handler Control and State 155 0xD28 FAULTSTAT R/W1C 0x0000.0000 Configurable Fault Status 159 0xD2C HFAULTSTAT R/W1C 0x0000.0000 Hard Fault Status 165 0xD34 MMADDR R/W - Memory Management Fault Address 166 0xD38 FAULTADDR R/W - Bus Fault Address 167 Memory Protection Unit (MPU) Registers 0xD90 MPUTYPE RO 0x0000.0800 MPU Type 168 0xD94 MPUCTRL R/W 0x0000.0000 MPU Control 169 0xD98 MPUNUMBER R/W 0x0000.0000 MPU Region Number 171 0xD9C MPUBASE R/W 0x0000.0000 MPU Region Base Address 172 0xDA0 MPUATTR R/W 0x0000.0000 MPU Region Attribute and Size 174 120 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Table 3-7. Peripherals Register Map (continued) Name Type Reset 0xDA4 MPUBASE1 R/W 0x0000.0000 MPU Region Base Address Alias 1 172 0xDA8 MPUATTR1 R/W 0x0000.0000 MPU Region Attribute and Size Alias 1 174 0xDAC MPUBASE2 R/W 0x0000.0000 MPU Region Base Address Alias 2 172 0xDB0 MPUATTR2 R/W 0x0000.0000 MPU Region Attribute and Size Alias 2 174 0xDB4 MPUBASE3 R/W 0x0000.0000 MPU Region Base Address Alias 3 172 0xDB8 MPUATTR3 R/W 0x0000.0000 MPU Region Attribute and Size Alias 3 174 3.3 Description See page Offset System Timer (SysTick) Register Descriptions This section lists and describes the System Timer registers, in numerical order by address offset. July 03, 2014 121 Texas Instruments-Production Data Cortex-M3 Peripherals Register 1: SysTick Control and Status Register (STCTRL), offset 0x010 Note: This register can only be accessed from privileged mode. The SysTick STCTRL register enables the SysTick features. SysTick Control and Status Register (STCTRL) Base 0xE000.E000 Offset 0x010 Type R/W, reset 0x0000.0004 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 reserved Type Reset RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 9 8 7 6 5 4 3 reserved Type Reset RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 16 COUNT RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 2 1 0 CLK_SRC INTEN ENABLE R/W 1 R/W 0 R/W 0 Bit/Field Name Type Reset Description 31:17 reserved RO 0x000 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 16 COUNT RO 0 Count Flag Value Description 0 The SysTick timer has not counted to 0 since the last time this bit was read. 1 The SysTick timer has counted to 0 since the last time this bit was read. This bit is cleared by a read of the register or if the STCURRENT register is written with any value. If read by the debugger using the DAP, this bit is cleared only if the MasterType bit in the AHB-AP Control Register is clear. Otherwise, the COUNT bit is not changed by the debugger read. See the ARM® Debug Interface V5 Architecture Specification for more information on MasterType. 15:3 reserved RO 0x000 2 CLK_SRC R/W 1 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. Clock Source Value Description 0 External reference clock. (Not implemented for most Stellaris microcontrollers.) 1 System clock Because an external reference clock is not implemented, this bit must be set in order for SysTick to operate. 122 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Bit/Field Name Type Reset 1 INTEN R/W 0 0 ENABLE R/W 0 Description Interrupt Enable Value Description 0 Interrupt generation is disabled. Software can use the COUNT bit to determine if the counter has ever reached 0. 1 An interrupt is generated to the NVIC when SysTick counts to 0. Enable Value Description 0 The counter is disabled. 1 Enables SysTick to operate in a multi-shot way. That is, the counter loads the RELOAD value and begins counting down. On reaching 0, the COUNT bit is set and an interrupt is generated if enabled by INTEN. The counter then loads the RELOAD value again and begins counting. July 03, 2014 123 Texas Instruments-Production Data Cortex-M3 Peripherals Register 2: SysTick Reload Value Register (STRELOAD), offset 0x014 Note: This register can only be accessed from privileged mode. The STRELOAD register specifies the start value to load into the SysTick Current Value (STCURRENT) register when the counter reaches 0. The start value can be between 0x1 and 0x00FF.FFFF. A start value of 0 is possible but has no effect because the SysTick interrupt and the COUNT bit are activated when counting from 1 to 0. SysTick can be configured as a multi-shot timer, repeated over and over, firing every N+1 clock pulses, where N is any value from 1 to 0x00FF.FFFF. For example, if a tick interrupt is required every 100 clock pulses, 99 must be written into the RELOAD field. SysTick Reload Value Register (STRELOAD) Base 0xE000.E000 Offset 0x014 Type R/W, reset 0x0000.0000 31 30 29 28 RO 0 RO 0 RO 0 RO 0 15 14 13 R/W 0 R/W 0 R/W 0 27 26 25 24 23 22 21 20 18 17 16 RO 0 RO 0 RO 0 RO 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 12 11 10 9 8 7 6 5 4 3 2 1 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 reserved Type Reset 19 RELOAD RELOAD Type Reset Bit/Field Name Type Reset Description 31:24 reserved RO 0x00 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 23:0 RELOAD R/W 0x00.0000 Reload Value Value to load into the SysTick Current Value (STCURRENT) register when the counter reaches 0. 124 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 3: SysTick Current Value Register (STCURRENT), offset 0x018 Note: This register can only be accessed from privileged mode. The STCURRENT register contains the current value of the SysTick counter. SysTick Current Value Register (STCURRENT) Base 0xE000.E000 Offset 0x018 Type R/WC, reset 0x0000.0000 31 30 29 28 27 26 25 24 23 22 21 reserved Type Reset 20 19 18 17 16 CURRENT RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 R/WC 0 R/WC 0 R/WC 0 R/WC 0 R/WC 0 R/WC 0 R/WC 0 R/WC 0 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 R/WC 0 R/WC 0 R/WC 0 R/WC 0 R/WC 0 R/WC 0 R/WC 0 CURRENT Type Reset R/WC 0 R/WC 0 R/WC 0 R/WC 0 R/WC 0 R/WC 0 R/WC 0 R/WC 0 R/WC 0 Bit/Field Name Type Reset Description 31:24 reserved RO 0x00 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 23:0 CURRENT R/WC 0x00.0000 Current Value This field contains the current value at the time the register is accessed. No read-modify-write protection is provided, so change with care. This register is write-clear. Writing to it with any value clears the register. Clearing this register also clears the COUNT bit of the STCTRL register. 3.4 NVIC Register Descriptions This section lists and describes the NVIC registers, in numerical order by address offset. The NVIC registers can only be fully accessed from privileged mode, but interrupts can be pended while in unprivileged mode by enabling the Configuration and Control (CFGCTRL) register. Any other unprivileged mode access causes a bus fault. Ensure software uses correctly aligned register accesses. The processor does not support unaligned accesses to NVIC registers. An interrupt can enter the pending state even if it is disabled. Before programming the VTABLE register to relocate the vector table, ensure the vector table entries of the new vector table are set up for fault handlers, NMI, and all enabled exceptions such as interrupts. For more information, see page 145. July 03, 2014 125 Texas Instruments-Production Data Cortex-M3 Peripherals Register 4: Interrupt 0-31 Set Enable (EN0), offset 0x100 Note: This register can only be accessed from privileged mode. See Table 2-9 on page 99 for interrupt assignments. If a pending interrupt is enabled, the NVIC activates the interrupt based on its priority. If an interrupt is not enabled, asserting its interrupt signal changes the interrupt state to pending, but the NVIC never activates the interrupt, regardless of its priority. Interrupt 0-31 Set Enable (EN0) Base 0xE000.E000 Offset 0x100 Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 INT Type Reset INT Type Reset Bit/Field Name Type 31:0 INT R/W Reset Description 0x0000.0000 Interrupt Enable Value Description 0 On a read, indicates the interrupt is disabled. On a write, no effect. 1 On a read, indicates the interrupt is enabled. On a write, enables the interrupt. A bit can only be cleared by setting the corresponding INT[n] bit in the DISn register. 126 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 5: Interrupt 32-54 Set Enable (EN1), offset 0x104 Note: This register can only be accessed from privileged mode. The EN1 register enables interrupts and shows which interrupts are enabled. Bit 0 corresponds to Interrupt 32; bit 22 corresponds to Interrupt 54. See Table 2-9 on page 99 for interrupt assignments. If a pending interrupt is enabled, the NVIC activates the interrupt based on its priority. If an interrupt is not enabled, asserting its interrupt signal changes the interrupt state to pending, but the NVIC never activates the interrupt, regardless of its priority. Interrupt 32-54 Set Enable (EN1) Base 0xE000.E000 Offset 0x104 Type R/W, reset 0x0000.0000 31 30 29 28 RO 0 RO 0 RO 0 RO 0 15 14 13 R/W 0 R/W 0 R/W 0 27 26 25 24 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 12 11 10 9 8 7 6 5 4 3 2 1 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 reserved Type Reset INT INT Type Reset Bit/Field Name Type Reset Description 31:23 reserved RO 0x00 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 22:0 INT R/W 0x00.0000 Interrupt Enable Value Description 0 On a read, indicates the interrupt is disabled. On a write, no effect. 1 On a read, indicates the interrupt is enabled. On a write, enables the interrupt. A bit can only be cleared by setting the corresponding INT[n] bit in the DIS1 register. July 03, 2014 127 Texas Instruments-Production Data Cortex-M3 Peripherals Register 6: Interrupt 0-31 Clear Enable (DIS0), offset 0x180 Note: This register can only be accessed from privileged mode. See Table 2-9 on page 99 for interrupt assignments. Interrupt 0-31 Clear Enable (DIS0) Base 0xE000.E000 Offset 0x180 Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 7 6 5 4 3 2 1 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 INT Type Reset R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 15 14 13 12 11 10 9 8 INT Type Reset R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 Bit/Field Name Type 31:0 INT R/W R/W 0 Reset R/W 0 Description 0x0000.0000 Interrupt Disable Value Description 0 On a read, indicates the interrupt is disabled. On a write, no effect. 1 On a read, indicates the interrupt is enabled. On a write, clears the corresponding INT[n] bit in the EN0 register, disabling interrupt [n]. 128 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 7: Interrupt 32-54 Clear Enable (DIS1), offset 0x184 Note: This register can only be accessed from privileged mode. The DIS1 register disables interrupts. Bit 0 corresponds to Interrupt 32; bit 22 corresponds to Interrupt 54. See Table 2-9 on page 99 for interrupt assignments. Interrupt 32-54 Clear Enable (DIS1) Base 0xE000.E000 Offset 0x184 Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 23 22 21 20 reserved Type Reset 19 18 17 16 INT RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 8 RO 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 7 6 5 4 3 2 1 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 INT Type Reset R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 Bit/Field Name Type Reset Description 31:23 reserved RO 0x00 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 22:0 INT R/W 0x00.0000 Interrupt Disable Value Description 0 On a read, indicates the interrupt is disabled. On a write, no effect. 1 On a read, indicates the interrupt is enabled. On a write, clears the corresponding INT[n] bit in the EN1 register, disabling interrupt [n]. July 03, 2014 129 Texas Instruments-Production Data Cortex-M3 Peripherals Register 8: Interrupt 0-31 Set Pending (PEND0), offset 0x200 Note: This register can only be accessed from privileged mode. See Table 2-9 on page 99 for interrupt assignments. Interrupt 0-31 Set Pending (PEND0) Base 0xE000.E000 Offset 0x200 Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 7 6 5 4 3 2 1 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 INT Type Reset R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 15 14 13 12 11 10 9 8 INT Type Reset R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 Bit/Field Name Type 31:0 INT R/W R/W 0 Reset R/W 0 Description 0x0000.0000 Interrupt Set Pending Value Description 0 On a read, indicates that the interrupt is not pending. On a write, no effect. 1 On a read, indicates that the interrupt is pending. On a write, the corresponding interrupt is set to pending even if it is disabled. If the corresponding interrupt is already pending, setting a bit has no effect. A bit can only be cleared by setting the corresponding INT[n] bit in the UNPEND0 register. 130 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 9: Interrupt 32-54 Set Pending (PEND1), offset 0x204 Note: This register can only be accessed from privileged mode. The PEND1 register forces interrupts into the pending state and shows which interrupts are pending. Bit 0 corresponds to Interrupt 32; bit 22 corresponds to Interrupt 54. See Table 2-9 on page 99 for interrupt assignments. Interrupt 32-54 Set Pending (PEND1) Base 0xE000.E000 Offset 0x204 Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 23 22 21 20 reserved Type Reset 19 18 17 16 INT RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 8 RO 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 7 6 5 4 3 2 1 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 INT Type Reset R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 Bit/Field Name Type Reset Description 31:23 reserved RO 0x00 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 22:0 INT R/W 0x00.0000 Interrupt Set Pending Value Description 0 On a read, indicates that the interrupt is not pending. On a write, no effect. 1 On a read, indicates that the interrupt is pending. On a write, the corresponding interrupt is set to pending even if it is disabled. If the corresponding interrupt is already pending, setting a bit has no effect. A bit can only be cleared by setting the corresponding INT[n] bit in the UNPEND1 register. July 03, 2014 131 Texas Instruments-Production Data Cortex-M3 Peripherals Register 10: Interrupt 0-31 Clear Pending (UNPEND0), offset 0x280 Note: This register can only be accessed from privileged mode. See Table 2-9 on page 99 for interrupt assignments. Interrupt 0-31 Clear Pending (UNPEND0) Base 0xE000.E000 Offset 0x280 Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 7 6 5 4 3 2 1 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 INT Type Reset R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 15 14 13 12 11 10 9 8 INT Type Reset R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 Bit/Field Name Type 31:0 INT R/W R/W 0 Reset R/W 0 Description 0x0000.0000 Interrupt Clear Pending Value Description 0 On a read, indicates that the interrupt is not pending. On a write, no effect. 1 On a read, indicates that the interrupt is pending. On a write, clears the corresponding INT[n] bit in the PEND0 register, so that interrupt [n] is no longer pending. Setting a bit does not affect the active state of the corresponding interrupt. 132 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 11: Interrupt 32-54 Clear Pending (UNPEND1), offset 0x284 Note: This register can only be accessed from privileged mode. The UNPEND1 register shows which interrupts are pending and removes the pending state from interrupts. Bit 0 corresponds to Interrupt 32; bit 22 corresponds to Interrupt 54. See Table 2-9 on page 99 for interrupt assignments. Interrupt 32-54 Clear Pending (UNPEND1) Base 0xE000.E000 Offset 0x284 Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 23 22 21 20 reserved Type Reset 19 18 17 16 INT RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 8 RO 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 7 6 5 4 3 2 1 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 INT Type Reset R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 Bit/Field Name Type Reset Description 31:23 reserved RO 0x00 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 22:0 INT R/W 0x00.0000 Interrupt Clear Pending Value Description 0 On a read, indicates that the interrupt is not pending. On a write, no effect. 1 On a read, indicates that the interrupt is pending. On a write, clears the corresponding INT[n] bit in the PEND1 register, so that interrupt [n] is no longer pending. Setting a bit does not affect the active state of the corresponding interrupt. July 03, 2014 133 Texas Instruments-Production Data Cortex-M3 Peripherals Register 12: Interrupt 0-31 Active Bit (ACTIVE0), offset 0x300 Note: This register can only be accessed from privileged mode. See Table 2-9 on page 99 for interrupt assignments. Caution – Do not manually set or clear the bits in this register. Interrupt 0-31 Active Bit (ACTIVE0) Base 0xE000.E000 Offset 0x300 Type RO, reset 0x0000.0000 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 7 6 5 4 3 2 1 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 INT Type Reset RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 8 INT Type Reset RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 Bit/Field Name Type 31:0 INT RO RO 0 Reset RO 0 Description 0x0000.0000 Interrupt Active Value Description 0 The corresponding interrupt is not active. 1 The corresponding interrupt is active, or active and pending. 134 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 13: Interrupt 32-54 Active Bit (ACTIVE1), offset 0x304 Note: This register can only be accessed from privileged mode. The ACTIVE1 register indicates which interrupts are active. Bit 0 corresponds to Interrupt 32; bit 22 corresponds to Interrupt 54. See Table 2-9 on page 99 for interrupt assignments. Caution – Do not manually set or clear the bits in this register. Interrupt 32-54 Active Bit (ACTIVE1) Base 0xE000.E000 Offset 0x304 Type RO, reset 0x0000.0000 31 30 29 28 27 26 25 24 23 22 21 20 reserved Type Reset 19 18 17 16 INT RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 8 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 7 6 5 4 3 2 1 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 INT Type Reset RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 Bit/Field Name Type Reset Description 31:23 reserved RO 0x00 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 22:0 INT RO 0x00.0000 Interrupt Active Value Description 0 The corresponding interrupt is not active. 1 The corresponding interrupt is active, or active and pending. July 03, 2014 135 Texas Instruments-Production Data Cortex-M3 Peripherals Register 14: Interrupt 0-3 Priority (PRI0), offset 0x400 Register 15: Interrupt 4-7 Priority (PRI1), offset 0x404 Register 16: Interrupt 8-11 Priority (PRI2), offset 0x408 Register 17: Interrupt 12-15 Priority (PRI3), offset 0x40C Register 18: Interrupt 16-19 Priority (PRI4), offset 0x410 Register 19: Interrupt 20-23 Priority (PRI5), offset 0x414 Register 20: Interrupt 24-27 Priority (PRI6), offset 0x418 Register 21: Interrupt 28-31 Priority (PRI7), offset 0x41C Register 22: Interrupt 32-35 Priority (PRI8), offset 0x420 Register 23: Interrupt 36-39 Priority (PRI9), offset 0x424 Register 24: Interrupt 40-43 Priority (PRI10), offset 0x428 Register 25: Interrupt 44-47 Priority (PRI11), offset 0x42C Register 26: Interrupt 48-51 Priority (PRI12), offset 0x430 Register 27: Interrupt 52-54 Priority (PRI13), offset 0x434 Note: This register can only be accessed from privileged mode. The PRIn registers provide 3-bit priority fields for each interrupt. These registers are byte accessible. Each register holds four priority fields that are assigned to interrupts as follows: PRIn Register Bit Field Interrupt Bits 31:29 Interrupt [4n+3] Bits 23:21 Interrupt [4n+2] Bits 15:13 Interrupt [4n+1] Bits 7:5 Interrupt [4n] See Table 2-9 on page 99 for interrupt assignments. Each priority level can be split into separate group priority and subpriority fields. The PRIGROUP field in the Application Interrupt and Reset Control (APINT) register (see page 146) indicates the position of the binary point that splits the priority and subpriority fields. These registers can only be accessed from privileged mode. 136 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Interrupt 0-3 Priority (PRI0) Base 0xE000.E000 Offset 0x400 Type R/W, reset 0x0000.0000 31 30 29 28 27 INTD Type Reset 25 24 23 reserved 22 21 20 19 INTC 18 17 16 reserved R/W 0 R/W 0 R/W 0 RO 0 RO 0 RO 0 RO 0 RO 0 R/W 0 R/W 0 R/W 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 R/W 0 RO 0 RO 0 RO 0 RO 0 R/W 0 R/W 0 RO 0 RO 0 RO 0 RO 0 INTB Type Reset 26 R/W 0 R/W 0 reserved RO 0 INTA Bit/Field Name Type Reset 31:29 INTD R/W 0x0 R/W 0 reserved RO 0 Description Interrupt Priority for Interrupt [4n+3] This field holds a priority value, 0-7, for the interrupt with the number [4n+3], where n is the number of the Interrupt Priority register (n=0 for PRI0, and so on). The lower the value, the greater the priority of the corresponding interrupt. 28:24 reserved RO 0x0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 23:21 INTC R/W 0x0 Interrupt Priority for Interrupt [4n+2] This field holds a priority value, 0-7, for the interrupt with the number [4n+2], where n is the number of the Interrupt Priority register (n=0 for PRI0, and so on). The lower the value, the greater the priority of the corresponding interrupt. 20:16 reserved RO 0x0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 15:13 INTB R/W 0x0 Interrupt Priority for Interrupt [4n+1] This field holds a priority value, 0-7, for the interrupt with the number [4n+1], where n is the number of the Interrupt Priority register (n=0 for PRI0, and so on). The lower the value, the greater the priority of the corresponding interrupt. 12:8 reserved RO 0x0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 7:5 INTA R/W 0x0 Interrupt Priority for Interrupt [4n] This field holds a priority value, 0-7, for the interrupt with the number [4n], where n is the number of the Interrupt Priority register (n=0 for PRI0, and so on). The lower the value, the greater the priority of the corresponding interrupt. 4:0 reserved RO 0x0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. July 03, 2014 137 Texas Instruments-Production Data Cortex-M3 Peripherals Register 28: Software Trigger Interrupt (SWTRIG), offset 0xF00 Note: Only privileged software can enable unprivileged access to the SWTRIG register. Writing an interrupt number to the SWTRIG register generates a Software Generated Interrupt (SGI). See Table 2-9 on page 99 for interrupt assignments. When the MAINPEND bit in the Configuration and Control (CFGCTRL) register (see page 150) is set, unprivileged software can access the SWTRIG register. Software Trigger Interrupt (SWTRIG) Base 0xE000.E000 Offset 0xF00 Type WO, reset 0x0000.0000 31 30 29 28 27 26 25 24 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 8 7 6 5 4 3 2 1 0 RO 0 RO 0 RO 0 WO 0 WO 0 WO 0 WO 0 WO 0 WO 0 reserved Type Reset reserved Type Reset RO 0 INTID Bit/Field Name Type Reset 31:6 reserved RO 0x0000.00 5:0 INTID WO 0x00 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. Interrupt ID This field holds the interrupt ID of the required SGI. For example, a value of 0x3 generates an interrupt on IRQ3. 3.5 System Control Block (SCB) Register Descriptions This section lists and describes the System Control Block (SCB) registers, in numerical order by address offset. The SCB registers can only be accessed from privileged mode. All registers must be accessed with aligned word accesses except for the FAULTSTAT and SYSPRI1-SYSPRI3 registers, which can be accessed with byte or aligned halfword or word accesses. The processor does not support unaligned accesses to system control block registers. 138 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 29: Auxiliary Control (ACTLR), offset 0x008 Note: This register can only be accessed from privileged mode. The ACTLR register provides disable bits for IT folding, write buffer use for accesses to the default memory map, and interruption of multi-cycle instructions. By default, this register is set to provide optimum performance from the Cortex-M3 processor and does not normally require modification. Auxiliary Control (ACTLR) Base 0xE000.E000 Offset 0x008 Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 2 1 0 reserved Type Reset RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 9 8 7 6 5 4 3 reserved Type Reset RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 DISFOLD DISWBUF DISMCYC RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 R/W 0 R/W 0 R/W 0 Bit/Field Name Type Reset Description 31:3 reserved RO 0x00 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 2 DISFOLD R/W 0 Disable IT Folding Value Description 0 No effect. 1 Disables IT folding. In some situations, the processor can start executing the first instruction in an IT block while it is still executing the IT instruction. This behavior is called IT folding, and improves performance, However, IT folding can cause jitter in looping. If a task must avoid jitter, set the DISFOLD bit before executing the task, to disable IT folding. 1 DISWBUF R/W 0 Disable Write Buffer Value Description 0 No effect. 1 Disables write buffer use during default memory map accesses. In this situation, all bus faults are precise bus faults but performance is decreased because any store to memory must complete before the processor can execute the next instruction. Note: This bit only affects write buffers implemented in the Cortex-M3 processor. July 03, 2014 139 Texas Instruments-Production Data Cortex-M3 Peripherals Bit/Field Name Type Reset 0 DISMCYC R/W 0 Description Disable Interrupts of Multiple Cycle Instructions Value Description 0 No effect. 1 Disables interruption of load multiple and store multiple instructions. In this situation, the interrupt latency of the processor is increased because any LDM or STM must complete before the processor can stack the current state and enter the interrupt handler. 140 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 30: CPU ID Base (CPUID), offset 0xD00 Note: This register can only be accessed from privileged mode. The CPUID register contains the ARM® Cortex™-M3 processor part number, version, and implementation information. CPU ID Base (CPUID) Base 0xE000.E000 Offset 0xD00 Type RO, reset 0x412F.C230 31 30 29 28 27 26 25 24 23 22 IMP Type Reset 21 20 19 18 VAR RO 0 RO 1 RO 0 RO 0 RO 0 RO 0 RO 0 RO 1 RO 0 RO 0 RO 1 RO 0 RO 1 RO 1 15 14 13 12 11 10 9 8 7 6 5 4 3 2 PARTNO Type Reset RO 1 RO 1 RO 0 RO 0 RO 0 RO 0 RO 1 17 16 RO 1 RO 1 1 0 RO 0 RO 0 CON REV RO 0 RO 0 RO 0 Bit/Field Name Type Reset Description 31:24 IMP RO 0x41 Implementer Code RO 1 RO 1 RO 0 RO 0 Value Description 0x41 ARM 23:20 VAR RO 0x2 Variant Number Value Description 0x2 19:16 CON RO 0xF The rn value in the rnpn product revision identifier, for example, the 2 in r2p0. Constant Value Description 0xF 15:4 PARTNO RO 0xC23 Always reads as 0xF. Part Number Value Description 0xC23 Cortex-M3 processor. 3:0 REV RO 0x0 Revision Number Value Description 0x0 The pn value in the rnpn product revision identifier, for example, the 0 in r2p0. July 03, 2014 141 Texas Instruments-Production Data Cortex-M3 Peripherals Register 31: Interrupt Control and State (INTCTRL), offset 0xD04 Note: This register can only be accessed from privileged mode. The INCTRL register provides a set-pending bit for the NMI exception, and set-pending and clear-pending bits for the PendSV and SysTick exceptions. In addition, bits in this register indicate the exception number of the exception being processed, whether there are preempted active exceptions, the exception number of the highest priority pending exception, and whether any interrupts are pending. When writing to INCTRL, the effect is unpredictable when writing a 1 to both the PENDSV and UNPENDSV bits, or writing a 1 to both the PENDSTSET and PENDSTCLR bits. Interrupt Control and State (INTCTRL) Base 0xE000.E000 Offset 0xD04 Type R/W, reset 0x0000.0000 31 NMISET Type Reset 30 29 reserved 28 26 PENDSV UNPENDSV 25 PENDSTSET PENDSTCLR 24 reserved 23 22 21 ISRPRE ISRPEND 20 19 18 reserved 17 16 VECPEND R/W 0 RO 0 RO 0 R/W 0 WO 0 R/W 0 WO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 VECPEND Type Reset 27 RO 0 RETBASE RO 0 reserved RO 0 Bit/Field Name Type Reset 31 NMISET R/W 0 VECACT RO 0 Description NMI Set Pending Value Description 0 On a read, indicates an NMI exception is not pending. On a write, no effect. 1 On a read, indicates an NMI exception is pending. On a write, changes the NMI exception state to pending. Because NMI is the highest-priority exception, normally the processor enters the NMI exception handler as soon as it registers the setting of this bit, and clears this bit on entering the interrupt handler. A read of this bit by the NMI exception handler returns 1 only if the NMI signal is reasserted while the processor is executing that handler. 30:29 reserved RO 0x0 28 PENDSV R/W 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. PendSV Set Pending Value Description 0 On a read, indicates a PendSV exception is not pending. On a write, no effect. 1 On a read, indicates a PendSV exception is pending. On a write, changes the PendSV exception state to pending. Setting this bit is the only way to set the PendSV exception state to pending. This bit is cleared by writing a 1 to the UNPENDSV bit. 142 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Bit/Field Name Type Reset 27 UNPENDSV WO 0 Description PendSV Clear Pending Value Description 0 On a write, no effect. 1 On a write, removes the pending state from the PendSV exception. This bit is write only; on a register read, its value is unknown. 26 PENDSTSET R/W 0 SysTick Set Pending Value Description 0 On a read, indicates a SysTick exception is not pending. On a write, no effect. 1 On a read, indicates a SysTick exception is pending. On a write, changes the SysTick exception state to pending. This bit is cleared by writing a 1 to the PENDSTCLR bit. 25 PENDSTCLR WO 0 SysTick Clear Pending Value Description 0 On a write, no effect. 1 On a write, removes the pending state from the SysTick exception. This bit is write only; on a register read, its value is unknown. 24 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 23 ISRPRE RO 0 Debug Interrupt Handling Value Description 0 The release from halt does not take an interrupt. 1 The release from halt takes an interrupt. This bit is only meaningful in Debug mode and reads as zero when the processor is not in Debug mode. 22 ISRPEND RO 0 Interrupt Pending Value Description 0 No interrupt is pending. 1 An interrupt is pending. This bit provides status for all interrupts excluding NMI and Faults. 21:19 reserved RO 0x0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. July 03, 2014 143 Texas Instruments-Production Data Cortex-M3 Peripherals Bit/Field Name Type Reset Description 18:12 VECPEND RO 0x00 Interrupt Pending Vector Number This field contains the exception number of the highest priority pending enabled exception. The value indicated by this field includes the effect of the BASEPRI and FAULTMASK registers, but not any effect of the PRIMASK register. Value Description 0x00 No exceptions are pending 0x01 Reserved 0x02 NMI 0x03 Hard fault 0x04 Memory management fault 0x05 Bus fault 0x06 Usage fault 0x07-0x0A Reserved 0x0B SVCall 0x0C Reserved for Debug 0x0D Reserved 0x0E PendSV 0x0F SysTick 0x10 Interrupt Vector 0 0x11 Interrupt Vector 1 ... ... 0x46 Interrupt Vector 54 0x47-0x7F Reserved 11 RETBASE RO 0 Return to Base Value Description 0 There are preempted active exceptions to execute. 1 There are no active exceptions, or the currently executing exception is the only active exception. This bit provides status for all interrupts excluding NMI and Faults. This bit only has meaning if the processor is currently executing an ISR (the Interrupt Program Status (IPSR) register is non-zero). 10:7 reserved RO 0x0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 6:0 VECACT RO 0x00 Interrupt Pending Vector Number This field contains the active exception number. The exception numbers can be found in the description for the VECPEND field. If this field is clear, the processor is in Thread mode. This field contains the same value as the ISRNUM field in the IPSR register. Subtract 16 from this value to obtain the IRQ number required to index into the Interrupt Set Enable (ENn), Interrupt Clear Enable (DISn), Interrupt Set Pending (PENDn), Interrupt Clear Pending (UNPENDn), and Interrupt Priority (PRIn) registers (see page 79). 144 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 32: Vector Table Offset (VTABLE), offset 0xD08 Note: This register can only be accessed from privileged mode. The VTABLE register indicates the offset of the vector table base address from memory address 0x0000.0000. Vector Table Offset (VTABLE) Base 0xE000.E000 Offset 0xD08 Type R/W, reset 0x0000.0000 31 30 reserved Type Reset 29 28 27 26 25 24 23 BASE RO 0 RO 0 R/W 0 15 14 13 22 21 20 19 18 17 16 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 4 3 2 1 0 RO 0 RO 0 RO 0 RO 0 OFFSET R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 12 11 10 9 8 7 6 5 OFFSET Type Reset R/W 0 R/W 0 R/W 0 R/W 0 reserved R/W 0 R/W 0 R/W 0 Bit/Field Name Type Reset 31:30 reserved RO 0x0 29 BASE R/W 0 RO 0 RO 0 RO 0 RO 0 RO 0 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. Vector Table Base Value Description 28:9 OFFSET R/W 0x000.00 0 The vector table is in the code memory region. 1 The vector table is in the SRAM memory region. Vector Table Offset When configuring the OFFSET field, the offset must be aligned to the number of exception entries in the vector table. Because there are 54 interrupts, the offset must be aligned on a 512-byte boundary. 8:0 reserved RO 0x00 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. July 03, 2014 145 Texas Instruments-Production Data Cortex-M3 Peripherals Register 33: Application Interrupt and Reset Control (APINT), offset 0xD0C Note: This register can only be accessed from privileged mode. The APINT register provides priority grouping control for the exception model, endian status for data accesses, and reset control of the system. To write to this register, 0x05FA must be written to the VECTKEY field, otherwise the write is ignored. The PRIGROUP field indicates the position of the binary point that splits the INTx fields in the Interrupt Priority (PRIx) registers into separate group priority and subpriority fields. Table 3-8 on page 146 shows how the PRIGROUP value controls this split. The bit numbers in the Group Priority Field and Subpriority Field columns in the table refer to the bits in the INTA field. For the INTB field, the corresponding bits are 15:13; for INTC, 23:21; and for INTD, 31:29. Note: Determining preemption of an exception uses only the group priority field. Table 3-8. Interrupt Priority Levels a PRIGROUP Bit Field Binary Point Group Priority Field Subpriority Field Group Priorities Subpriorities 0x0 - 0x4 bxxx. [7:5] None 8 1 0x5 bxx.y [7:6] [5] 4 2 0x6 bx.yy [7] [6:5] 2 4 0x7 b.yyy None [7:5] 1 8 a. INTx field showing the binary point. An x denotes a group priority field bit, and a y denotes a subpriority field bit. Application Interrupt and Reset Control (APINT) Base 0xE000.E000 Offset 0xD0C Type R/W, reset 0xFA05.0000 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 R/W 0 R/W 0 R/W 0 R/W 1 R/W 0 R/W 1 5 4 3 2 1 0 VECTKEY Type Reset R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 0 15 14 13 12 11 10 reserved ENDIANESS Type Reset RO 0 RO 0 RO 0 RO 0 R/W 1 R/W 0 R/W 0 R/W 0 9 8 7 6 PRIGROUP RO 0 R/W 0 R/W 0 Bit/Field Name Type Reset 31:16 VECTKEY R/W 0xFA05 reserved R/W 0 RO 0 RO 0 RO 0 SYSRESREQ VECTCLRACT VECTRESET RO 0 RO 0 WO 0 WO 0 WO 0 Description Register Key This field is used to guard against accidental writes to this register. 0x05FA must be written to this field in order to change the bits in this register. On a read, 0xFA05 is returned. 15 ENDIANESS RO 0 Data Endianess The Stellaris implementation uses only little-endian mode so this is cleared to 0. 14:11 reserved RO 0x0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 146 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Bit/Field Name Type Reset 10:8 PRIGROUP R/W 0x0 Description Interrupt Priority Grouping This field determines the split of group priority from subpriority (see Table 3-8 on page 146 for more information). 7:3 reserved RO 0x0 2 SYSRESREQ WO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. System Reset Request Value Description 0 No effect. 1 Resets the core and all on-chip peripherals except the Debug interface. This bit is automatically cleared during the reset of the core and reads as 0. 1 VECTCLRACT WO 0 Clear Active NMI / Fault This bit is reserved for Debug use and reads as 0. This bit must be written as a 0, otherwise behavior is unpredictable. 0 VECTRESET WO 0 System Reset This bit is reserved for Debug use and reads as 0. This bit must be written as a 0, otherwise behavior is unpredictable. July 03, 2014 147 Texas Instruments-Production Data Cortex-M3 Peripherals Register 34: System Control (SYSCTRL), offset 0xD10 Note: This register can only be accessed from privileged mode. The SYSCTRL register controls features of entry to and exit from low-power state. System Control (SYSCTRL) Base 0xE000.E000 Offset 0xD10 Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 2 1 reserved Type Reset RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 10 9 8 7 6 5 reserved Type Reset RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 Bit/Field Name Type Reset 31:5 reserved RO 0x0000.00 4 SEVONPEND R/W 0 RO 0 RO 0 RO 0 RO 0 4 3 SEVONPEND reserved R/W 0 RO 0 SLEEPDEEP SLEEPEXIT R/W 0 R/W 0 0 reserved RO 0 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. Wake Up on Pending Value Description 0 Only enabled interrupts or events can wake up the processor; disabled interrupts are excluded. 1 Enabled events and all interrupts, including disabled interrupts, can wake up the processor. When an event or interrupt enters the pending state, the event signal wakes up the processor from WFE. If the processor is not waiting for an event, the event is registered and affects the next WFE. The processor also wakes up on execution of a SEV instruction or an external event. 3 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 2 SLEEPDEEP R/W 0 Deep Sleep Enable Value Description 0 Use Sleep mode as the low power mode. 1 Use Deep-sleep mode as the low power mode. 148 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Bit/Field Name Type Reset 1 SLEEPEXIT R/W 0 Description Sleep on ISR Exit Value Description 0 When returning from Handler mode to Thread mode, do not sleep when returning to Thread mode. 1 When returning from Handler mode to Thread mode, enter sleep or deep sleep on return from an ISR. Setting this bit enables an interrupt-driven application to avoid returning to an empty main application. 0 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. July 03, 2014 149 Texas Instruments-Production Data Cortex-M3 Peripherals Register 35: Configuration and Control (CFGCTRL), offset 0xD14 Note: This register can only be accessed from privileged mode. The CFGCTRL register controls entry to Thread mode and enables: the handlers for NMI, hard fault and faults escalated by the FAULTMASK register to ignore bus faults; trapping of divide by zero and unaligned accesses; and access to the SWTRIG register by unprivileged software (see page 138). Configuration and Control (CFGCTRL) Base 0xE000.E000 Offset 0xD14 Type R/W, reset 0x0000.0200 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 6 5 2 1 0 reserved Type Reset RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 reserved Type Reset RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 9 8 7 reserved STKALIGN BFHFNMIGN RO 0 RO 0 R/W 1 Bit/Field Name Type Reset 31:10 reserved RO 0x0000.00 9 STKALIGN R/W 1 R/W 0 RO 0 RO 0 RO 0 4 3 DIV0 UNALIGNED R/W 0 R/W 0 reserved MAINPEND BASETHR RO 0 R/W 0 R/W 0 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. Stack Alignment on Exception Entry Value Description 0 The stack is 4-byte aligned. 1 The stack is 8-byte aligned. On exception entry, the processor uses bit 9 of the stacked PSR to indicate the stack alignment. On return from the exception, it uses this stacked bit to restore the correct stack alignment. 8 BFHFNMIGN R/W 0 Ignore Bus Fault in NMI and Fault This bit enables handlers with priority -1 or -2 to ignore data bus faults caused by load and store instructions. The setting of this bit applies to the hard fault, NMI, and FAULTMASK escalated handlers. Value Description 0 Data bus faults caused by load and store instructions cause a lock-up. 1 Handlers running at priority -1 and -2 ignore data bus faults caused by load and store instructions. Set this bit only when the handler and its data are in absolutely safe memory. The normal use of this bit is to probe system devices and bridges to detect control path problems and fix them. 7:5 reserved RO 0x0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 150 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Bit/Field Name Type Reset 4 DIV0 R/W 0 Description Trap on Divide by 0 This bit enables faulting or halting when the processor executes an SDIV or UDIV instruction with a divisor of 0. Value Description 3 UNALIGNED R/W 0 0 Do not trap on divide by 0. A divide by zero returns a quotient of 0. 1 Trap on divide by 0. Trap on Unaligned Access Value Description 0 Do not trap on unaligned halfword and word accesses. 1 Trap on unaligned halfword and word accesses. An unaligned access generates a usage fault. Unaligned LDM, STM, LDRD, and STRD instructions always fault regardless of whether UNALIGNED is set. 2 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 1 MAINPEND R/W 0 Allow Main Interrupt Trigger Value Description 0 BASETHR R/W 0 0 Disables unprivileged software access to the SWTRIG register. 1 Enables unprivileged software access to the SWTRIG register (see page 138). Thread State Control Value Description 0 The processor can enter Thread mode only when no exception is active. 1 The processor can enter Thread mode from any level under the control of an EXC_RETURN value (see “Exception Return” on page 103 for more information). July 03, 2014 151 Texas Instruments-Production Data Cortex-M3 Peripherals Register 36: System Handler Priority 1 (SYSPRI1), offset 0xD18 Note: This register can only be accessed from privileged mode. The SYSPRI1 register configures the priority level, 0 to 7 of the usage fault, bus fault, and memory management fault exception handlers. This register is byte-accessible. System Handler Priority 1 (SYSPRI1) Base 0xE000.E000 Offset 0xD18 Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 23 reserved Type Reset RO 0 15 RO 0 RO 0 RO 0 RO 0 14 13 12 11 BUS Type Reset R/W 0 R/W 0 RO 0 RO 0 RO 0 R/W 0 10 9 8 7 reserved R/W 0 RO 0 22 21 20 19 USAGE RO 0 RO 0 R/W 0 R/W 0 RO 0 RO 0 6 5 4 3 MEM RO 0 RO 0 R/W 0 R/W 0 18 17 16 RO 0 RO 0 RO 0 2 1 0 RO 0 RO 0 reserved reserved R/W 0 RO 0 RO 0 RO 0 Bit/Field Name Type Reset Description 31:24 reserved RO 0x00 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 23:21 USAGE R/W 0x0 Usage Fault Priority This field configures the priority level of the usage fault. Configurable priority values are in the range 0-7, with lower values having higher priority. 20:16 reserved RO 0x0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 15:13 BUS R/W 0x0 Bus Fault Priority This field configures the priority level of the bus fault. Configurable priority values are in the range 0-7, with lower values having higher priority. 12:8 reserved RO 0x0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 7:5 MEM R/W 0x0 Memory Management Fault Priority This field configures the priority level of the memory management fault. Configurable priority values are in the range 0-7, with lower values having higher priority. 4:0 reserved RO 0x0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 152 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 37: System Handler Priority 2 (SYSPRI2), offset 0xD1C Note: This register can only be accessed from privileged mode. The SYSPRI2 register configures the priority level, 0 to 7 of the SVCall handler. This register is byte-accessible. System Handler Priority 2 (SYSPRI2) Base 0xE000.E000 Offset 0xD1C Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 23 SVC Type Reset 22 21 20 19 18 17 16 reserved R/W 0 R/W 0 R/W 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 reserved Type Reset RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 Bit/Field Name Type Reset 31:29 SVC R/W 0x0 RO 0 Description SVCall Priority This field configures the priority level of SVCall. Configurable priority values are in the range 0-7, with lower values having higher priority. 28:0 reserved RO 0x000.0000 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. July 03, 2014 153 Texas Instruments-Production Data Cortex-M3 Peripherals Register 38: System Handler Priority 3 (SYSPRI3), offset 0xD20 Note: This register can only be accessed from privileged mode. The SYSPRI3 register configures the priority level, 0 to 7 of the SysTick exception and PendSV handlers. This register is byte-accessible. System Handler Priority 3 (SYSPRI3) Base 0xE000.E000 Offset 0xD20 Type R/W, reset 0x0000.0000 31 30 29 28 27 TICK Type Reset 26 25 24 23 reserved R/W 0 R/W 0 R/W 0 RO 0 RO 0 RO 0 RO 0 RO 0 R/W 0 15 14 13 12 11 10 9 8 7 reserved Type Reset RO 0 RO 0 RO 0 RO 0 22 21 20 19 PENDSV R/W 0 R/W 0 RO 0 RO 0 6 5 4 3 DEBUG RO 0 RO 0 RO 0 Bit/Field Name Type Reset 31:29 TICK R/W 0x0 RO 0 R/W 0 R/W 0 18 17 16 RO 0 RO 0 RO 0 2 1 0 RO 0 RO 0 reserved reserved R/W 0 RO 0 RO 0 RO 0 Description SysTick Exception Priority This field configures the priority level of the SysTick exception. Configurable priority values are in the range 0-7, with lower values having higher priority. 28:24 reserved RO 0x0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 23:21 PENDSV R/W 0x0 PendSV Priority This field configures the priority level of PendSV. Configurable priority values are in the range 0-7, with lower values having higher priority. 20:8 reserved RO 0x000 7:5 DEBUG R/W 0x0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. Debug Priority This field configures the priority level of Debug. Configurable priority values are in the range 0-7, with lower values having higher priority. 4:0 reserved RO 0x0.0000 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 154 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 39: System Handler Control and State (SYSHNDCTRL), offset 0xD24 Note: This register can only be accessed from privileged mode. The SYSHNDCTRL register enables the system handlers, and indicates the pending status of the usage fault, bus fault, memory management fault, and SVC exceptions as well as the active status of the system handlers. If a system handler is disabled and the corresponding fault occurs, the processor treats the fault as a hard fault. This register can be modified to change the pending or active status of system exceptions. An OS kernel can write to the active bits to perform a context switch that changes the current exception type. Caution – Software that changes the value of an active bit in this register without correct adjustment to the stacked content can cause the processor to generate a fault exception. Ensure software that writes to this register retains and subsequently restores the current active status. If the value of a bit in this register must be modified after enabling the system handlers, a read-modify-write procedure must be used to ensure that only the required bit is modified. System Handler Control and State (SYSHNDCTRL) Base 0xE000.E000 Offset 0xD24 Type R/W, reset 0x0000.0000 31 30 29 28 27 26 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 SVC BUSP MEMP USAGEP R/W 0 R/W 0 R/W 0 R/W 0 25 24 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 USAGE BUS MEM R/W 0 R/W 0 R/W 0 10 9 8 7 6 5 4 3 2 1 0 TICK PNDSV reserved MON SVCA R/W 0 R/W 0 RO 0 R/W 0 R/W 0 USGA reserved BUSA MEMA R/W 0 RO 0 R/W 0 R/W 0 reserved Type Reset Type Reset reserved RO 0 RO 0 RO 0 Bit/Field Name Type Reset Description 31:19 reserved RO 0x000 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 18 USAGE R/W 0 Usage Fault Enable Value Description 17 BUS R/W 0 0 Disables the usage fault exception. 1 Enables the usage fault exception. Bus Fault Enable Value Description 0 Disables the bus fault exception. 1 Enables the bus fault exception. July 03, 2014 155 Texas Instruments-Production Data Cortex-M3 Peripherals Bit/Field Name Type Reset 16 MEM R/W 0 Description Memory Management Fault Enable Value Description 15 SVC R/W 0 0 Disables the memory management fault exception. 1 Enables the memory management fault exception. SVC Call Pending Value Description 0 An SVC call exception is not pending. 1 An SVC call exception is pending. This bit can be modified to change the pending status of the SVC call exception. 14 BUSP R/W 0 Bus Fault Pending Value Description 0 A bus fault exception is not pending. 1 A bus fault exception is pending. This bit can be modified to change the pending status of the bus fault exception. 13 MEMP R/W 0 Memory Management Fault Pending Value Description 0 A memory management fault exception is not pending. 1 A memory management fault exception is pending. This bit can be modified to change the pending status of the memory management fault exception. 12 USAGEP R/W 0 Usage Fault Pending Value Description 0 A usage fault exception is not pending. 1 A usage fault exception is pending. This bit can be modified to change the pending status of the usage fault exception. 11 TICK R/W 0 SysTick Exception Active Value Description 0 A SysTick exception is not active. 1 A SysTick exception is active. This bit can be modified to change the active status of the SysTick exception, however, see the Caution above before setting this bit. 156 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Bit/Field Name Type Reset 10 PNDSV R/W 0 Description PendSV Exception Active Value Description 0 A PendSV exception is not active. 1 A PendSV exception is active. This bit can be modified to change the active status of the PendSV exception, however, see the Caution above before setting this bit. 9 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 8 MON R/W 0 Debug Monitor Active Value Description 7 SVCA R/W 0 0 The Debug monitor is not active. 1 The Debug monitor is active. SVC Call Active Value Description 0 SVC call is not active. 1 SVC call is active. This bit can be modified to change the active status of the SVC call exception, however, see the Caution above before setting this bit. 6:4 reserved RO 0x0 3 USGA R/W 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. Usage Fault Active Value Description 0 Usage fault is not active. 1 Usage fault is active. This bit can be modified to change the active status of the usage fault exception, however, see the Caution above before setting this bit. 2 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 1 BUSA R/W 0 Bus Fault Active Value Description 0 Bus fault is not active. 1 Bus fault is active. This bit can be modified to change the active status of the bus fault exception, however, see the Caution above before setting this bit. July 03, 2014 157 Texas Instruments-Production Data Cortex-M3 Peripherals Bit/Field Name Type Reset 0 MEMA R/W 0 Description Memory Management Fault Active Value Description 0 Memory management fault is not active. 1 Memory management fault is active. This bit can be modified to change the active status of the memory management fault exception, however, see the Caution above before setting this bit. 158 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 40: Configurable Fault Status (FAULTSTAT), offset 0xD28 Note: This register can only be accessed from privileged mode. The FAULTSTAT register indicates the cause of a memory management fault, bus fault, or usage fault. Each of these functions is assigned to a subregister as follows: ■ Usage Fault Status (UFAULTSTAT), bits 31:16 ■ Bus Fault Status (BFAULTSTAT), bits 15:8 ■ Memory Management Fault Status (MFAULTSTAT), bits 7:0 FAULTSTAT is byte accessible. FAULTSTAT or its subregisters can be accessed as follows: ■ ■ ■ ■ ■ The complete FAULTSTAT register, with a word access to offset 0xD28 The MFAULTSTAT, with a byte access to offset 0xD28 The MFAULTSTAT and BFAULTSTAT, with a halfword access to offset 0xD28 The BFAULTSTAT, with a byte access to offset 0xD29 The UFAULTSTAT, with a halfword access to offset 0xD2A Bits are cleared by writing a 1 to them. In a fault handler, the true faulting address can be determined by: 1. Read and save the Memory Management Fault Address (MMADDR) or Bus Fault Address (FAULTADDR) value. 2. Read the MMARV bit in MFAULTSTAT, or the BFARV bit in BFAULTSTAT to determine if the MMADDR or FAULTADDR contents are valid. Software must follow this sequence because another higher priority exception might change the MMADDR or FAULTADDR value. For example, if a higher priority handler preempts the current fault handler, the other fault might change the MMADDR or FAULTADDR value. Configurable Fault Status (FAULTSTAT) Base 0xE000.E000 Offset 0xD28 Type R/W1C, reset 0x0000.0000 31 30 29 28 27 26 reserved Type Reset RO 0 RO 0 RO 0 15 14 13 BFARV Type Reset R/W1C 0 reserved RO 0 RO 0 RO 0 RO 0 RO 0 25 24 DIV0 UNALIGN R/W1C 0 R/W1C 0 23 22 21 20 reserved RO 0 RO 0 RO 0 6 5 12 11 10 9 8 7 BSTKE BUSTKE IMPRE PRECISE IBUS MMARV R/W1C 0 R/W1C 0 R/W1C 0 R/W1C 0 R/W1C 0 R/W1C 0 reserved RO 0 RO 0 RO 0 4 MSTKE R/W1C 0 19 18 17 16 NOCP INVPC INVSTAT UNDEF R/W1C 0 R/W1C 0 R/W1C 0 R/W1C 0 3 2 MUSTKE reserved R/W1C 0 RO 0 1 0 DERR IERR R/W1C 0 R/W1C 0 Bit/Field Name Type Reset Description 31:26 reserved RO 0x00 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. July 03, 2014 159 Texas Instruments-Production Data Cortex-M3 Peripherals Bit/Field Name Type Reset 25 DIV0 R/W1C 0 Description Divide-by-Zero Usage Fault Value Description 0 No divide-by-zero fault has occurred, or divide-by-zero trapping is not enabled. 1 The processor has executed an SDIV or UDIV instruction with a divisor of 0. When this bit is set, the PC value stacked for the exception return points to the instruction that performed the divide by zero. Trapping on divide-by-zero is enabled by setting the DIV0 bit in the Configuration and Control (CFGCTRL) register (see page 150). This bit is cleared by writing a 1 to it. 24 UNALIGN R/W1C 0 Unaligned Access Usage Fault Value Description 0 No unaligned access fault has occurred, or unaligned access trapping is not enabled. 1 The processor has made an unaligned memory access. Unaligned LDM, STM, LDRD, and STRD instructions always fault regardless of the configuration of this bit. Trapping on unaligned access is enabled by setting the UNALIGNED bit in the CFGCTRL register (see page 150). This bit is cleared by writing a 1 to it. 23:20 reserved RO 0x00 19 NOCP R/W1C 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. No Coprocessor Usage Fault Value Description 0 A usage fault has not been caused by attempting to access a coprocessor. 1 The processor has attempted to access a coprocessor. This bit is cleared by writing a 1 to it. 18 INVPC R/W1C 0 Invalid PC Load Usage Fault Value Description 0 A usage fault has not been caused by attempting to load an invalid PC value. 1 The processor has attempted an illegal load of EXC_RETURN to the PC as a result of an invalid context or an invalid EXC_RETURN value. When this bit is set, the PC value stacked for the exception return points to the instruction that tried to perform the illegal load of the PC. This bit is cleared by writing a 1 to it. 160 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Bit/Field Name Type Reset 17 INVSTAT R/W1C 0 Description Invalid State Usage Fault Value Description 0 A usage fault has not been caused by an invalid state. 1 The processor has attempted to execute an instruction that makes illegal use of the EPSR register. When this bit is set, the PC value stacked for the exception return points to the instruction that attempted the illegal use of the Execution Program Status Register (EPSR) register. This bit is not set if an undefined instruction uses the EPSR register. This bit is cleared by writing a 1 to it. 16 UNDEF R/W1C 0 Undefined Instruction Usage Fault Value Description 0 A usage fault has not been caused by an undefined instruction. 1 The processor has attempted to execute an undefined instruction. When this bit is set, the PC value stacked for the exception return points to the undefined instruction. An undefined instruction is an instruction that the processor cannot decode. This bit is cleared by writing a 1 to it. 15 BFARV R/W1C 0 Bus Fault Address Register Valid Value Description 0 The value in the Bus Fault Address (FAULTADDR) register is not a valid fault address. 1 The FAULTADDR register is holding a valid fault address. This bit is set after a bus fault, where the address is known. Other faults can clear this bit, such as a memory management fault occurring later. If a bus fault occurs and is escalated to a hard fault because of priority, the hard fault handler must clear this bit. This action prevents problems if returning to a stacked active bus fault handler whose FAULTADDR register value has been overwritten. This bit is cleared by writing a 1 to it. 14:13 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. July 03, 2014 161 Texas Instruments-Production Data Cortex-M3 Peripherals Bit/Field Name Type Reset 12 BSTKE R/W1C 0 Description Stack Bus Fault Value Description 0 No bus fault has occurred on stacking for exception entry. 1 Stacking for an exception entry has caused one or more bus faults. When this bit is set, the SP is still adjusted but the values in the context area on the stack might be incorrect. A fault address is not written to the FAULTADDR register. This bit is cleared by writing a 1 to it. 11 BUSTKE R/W1C 0 Unstack Bus Fault Value Description 0 No bus fault has occurred on unstacking for a return from exception. 1 Unstacking for a return from exception has caused one or more bus faults. This fault is chained to the handler. Thus, when this bit is set, the original return stack is still present. The SP is not adjusted from the failing return, a new save is not performed, and a fault address is not written to the FAULTADDR register. This bit is cleared by writing a 1 to it. 10 IMPRE R/W1C 0 Imprecise Data Bus Error Value Description 0 An imprecise data bus error has not occurred. 1 A data bus error has occurred, but the return address in the stack frame is not related to the instruction that caused the error. When this bit is set, a fault address is not written to the FAULTADDR register. This fault is asynchronous. Therefore, if the fault is detected when the priority of the current process is higher than the bus fault priority, the bus fault becomes pending and becomes active only when the processor returns from all higher-priority processes. If a precise fault occurs before the processor enters the handler for the imprecise bus fault, the handler detects that both the IMPRE bit is set and one of the precise fault status bits is set. This bit is cleared by writing a 1 to it. 9 PRECISE R/W1C 0 Precise Data Bus Error Value Description 0 A precise data bus error has not occurred. 1 A data bus error has occurred, and the PC value stacked for the exception return points to the instruction that caused the fault. When this bit is set, the fault address is written to the FAULTADDR register. This bit is cleared by writing a 1 to it. 162 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Bit/Field Name Type Reset 8 IBUS R/W1C 0 Description Instruction Bus Error Value Description 0 An instruction bus error has not occurred. 1 An instruction bus error has occurred. The processor detects the instruction bus error on prefetching an instruction, but sets this bit only if it attempts to issue the faulting instruction. When this bit is set, a fault address is not written to the FAULTADDR register. This bit is cleared by writing a 1 to it. 7 MMARV R/W1C 0 Memory Management Fault Address Register Valid Value Description 0 The value in the Memory Management Fault Address (MMADDR) register is not a valid fault address. 1 The MMADDR register is holding a valid fault address. If a memory management fault occurs and is escalated to a hard fault because of priority, the hard fault handler must clear this bit. This action prevents problems if returning to a stacked active memory management fault handler whose MMADDR register value has been overwritten. This bit is cleared by writing a 1 to it. 6:5 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 4 MSTKE R/W1C 0 Stack Access Violation Value Description 0 No memory management fault has occurred on stacking for exception entry. 1 Stacking for an exception entry has caused one or more access violations. When this bit is set, the SP is still adjusted but the values in the context area on the stack might be incorrect. A fault address is not written to the MMADDR register. This bit is cleared by writing a 1 to it. July 03, 2014 163 Texas Instruments-Production Data Cortex-M3 Peripherals Bit/Field Name Type Reset 3 MUSTKE R/W1C 0 Description Unstack Access Violation Value Description 0 No memory management fault has occurred on unstacking for a return from exception. 1 Unstacking for a return from exception has caused one or more access violations. This fault is chained to the handler. Thus, when this bit is set, the original return stack is still present. The SP is not adjusted from the failing return, a new save is not performed, and a fault address is not written to the MMADDR register. This bit is cleared by writing a 1 to it. 2 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 1 DERR R/W1C 0 Data Access Violation Value Description 0 A data access violation has not occurred. 1 The processor attempted a load or store at a location that does not permit the operation. When this bit is set, the PC value stacked for the exception return points to the faulting instruction and the address of the attempted access is written to the MMADDR register. This bit is cleared by writing a 1 to it. 0 IERR R/W1C 0 Instruction Access Violation Value Description 0 An instruction access violation has not occurred. 1 The processor attempted an instruction fetch from a location that does not permit execution. This fault occurs on any access to an XN region, even when the MPU is disabled or not present. When this bit is set, the PC value stacked for the exception return points to the faulting instruction and the address of the attempted access is not written to the MMADDR register. This bit is cleared by writing a 1 to it. 164 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 41: Hard Fault Status (HFAULTSTAT), offset 0xD2C Note: This register can only be accessed from privileged mode. The HFAULTSTAT register gives information about events that activate the hard fault handler. Bits are cleared by writing a 1 to them. Hard Fault Status (HFAULTSTAT) Base 0xE000.E000 Offset 0xD2C Type R/W1C, reset 0x0000.0000 Type Reset 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 DBG FORCED R/W1C 0 R/W1C 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 reserved RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 VECT reserved RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 R/W1C 0 RO 0 reserved Type Reset Bit/Field Name Type Reset 31 DBG R/W1C 0 Description Debug Event This bit is reserved for Debug use. This bit must be written as a 0, otherwise behavior is unpredictable. 30 FORCED R/W1C 0 Forced Hard Fault Value Description 0 No forced hard fault has occurred. 1 A forced hard fault has been generated by escalation of a fault with configurable priority that cannot be handled, either because of priority or because it is disabled. When this bit is set, the hard fault handler must read the other fault status registers to find the cause of the fault. This bit is cleared by writing a 1 to it. 29:2 reserved RO 0x00 1 VECT R/W1C 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. Vector Table Read Fault Value Description 0 No bus fault has occurred on a vector table read. 1 A bus fault occurred on a vector table read. This error is always handled by the hard fault handler. When this bit is set, the PC value stacked for the exception return points to the instruction that was preempted by the exception. This bit is cleared by writing a 1 to it. 0 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. July 03, 2014 165 Texas Instruments-Production Data Cortex-M3 Peripherals Register 42: Memory Management Fault Address (MMADDR), offset 0xD34 Note: This register can only be accessed from privileged mode. The MMADDR register contains the address of the location that generated a memory management fault. When an unaligned access faults, the address in the MMADDR register is the actual address that faulted. Because a single read or write instruction can be split into multiple aligned accesses, the fault address can be any address in the range of the requested access size. Bits in the Memory Management Fault Status (MFAULTSTAT) register indicate the cause of the fault and whether the value in the MMADDR register is valid (see page 159). Memory Management Fault Address (MMADDR) Base 0xE000.E000 Offset 0xD34 Type R/W, reset 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - 7 6 5 4 3 2 1 0 R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - ADDR Type Reset R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - 15 14 13 12 11 10 9 8 ADDR Type Reset R/W - R/W - R/W - R/W - R/W - R/W - R/W - Bit/Field Name Type Reset 31:0 ADDR R/W - R/W - Description Fault Address When the MMARV bit of MFAULTSTAT is set, this field holds the address of the location that generated the memory management fault. 166 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 43: Bus Fault Address (FAULTADDR), offset 0xD38 Note: This register can only be accessed from privileged mode. The FAULTADDR register contains the address of the location that generated a bus fault. When an unaligned access faults, the address in the FAULTADDR register is the one requested by the instruction, even if it is not the address of the fault. Bits in the Bus Fault Status (BFAULTSTAT) register indicate the cause of the fault and whether the value in the FAULTADDR register is valid (see page 159). Bus Fault Address (FAULTADDR) Base 0xE000.E000 Offset 0xD38 Type R/W, reset 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - 7 6 5 4 3 2 1 0 R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - ADDR Type Reset R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - 15 14 13 12 11 10 9 8 ADDR Type Reset R/W - R/W - R/W - R/W - R/W - R/W - R/W - Bit/Field Name Type Reset 31:0 ADDR R/W - R/W - Description Fault Address When the FAULTADDRV bit of BFAULTSTAT is set, this field holds the address of the location that generated the bus fault. 3.6 Memory Protection Unit (MPU) Register Descriptions This section lists and describes the Memory Protection Unit (MPU) registers, in numerical order by address offset. The MPU registers can only be accessed from privileged mode. July 03, 2014 167 Texas Instruments-Production Data Cortex-M3 Peripherals Register 44: MPU Type (MPUTYPE), offset 0xD90 Note: This register can only be accessed from privileged mode. The MPUTYPE register indicates whether the MPU is present, and if so, how many regions it supports. MPU Type (MPUTYPE) Base 0xE000.E000 Offset 0xD90 Type RO, reset 0x0000.0800 31 30 29 28 27 26 25 24 23 22 21 20 reserved Type Reset RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 8 7 6 5 DREGION Type Reset RO 0 RO 0 RO 0 RO 0 19 18 17 16 RO 0 IREGION RO 0 RO 0 RO 0 RO 0 4 3 2 1 reserved RO 1 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 0 SEPARATE RO 0 RO 0 RO 0 RO 0 Bit/Field Name Type Reset Description 31:24 reserved RO 0x00 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 23:16 IREGION RO 0x00 Number of I Regions This field indicates the number of supported MPU instruction regions. This field always contains 0x00. The MPU memory map is unified and is described by the DREGION field. 15:8 DREGION RO 0x08 Number of D Regions Value Description 0x08 Indicates there are eight supported MPU data regions. 7:1 reserved RO 0x00 0 SEPARATE RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. Separate or Unified MPU Value Description 0 Indicates the MPU is unified. 168 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 45: MPU Control (MPUCTRL), offset 0xD94 Note: This register can only be accessed from privileged mode. The MPUCTRL register enables the MPU, enables the default memory map background region, and enables use of the MPU when in the hard fault, Non-maskable Interrupt (NMI), and Fault Mask Register (FAULTMASK) escalated handlers. When the ENABLE and PRIVDEFEN bits are both set: ■ For privileged accesses, the default memory map is as described in “Memory Model” on page 87. Any access by privileged software that does not address an enabled memory region behaves as defined by the default memory map. ■ Any access by unprivileged software that does not address an enabled memory region causes a memory management fault. Execute Never (XN) and Strongly Ordered rules always apply to the System Control Space regardless of the value of the ENABLE bit. When the ENABLE bit is set, at least one region of the memory map must be enabled for the system to function unless the PRIVDEFEN bit is set. If the PRIVDEFEN bit is set and no regions are enabled, then only privileged software can operate. When the ENABLE bit is clear, the system uses the default memory map, which has the same memory attributes as if the MPU is not implemented (see Table 2-5 on page 90 for more information). The default memory map applies to accesses from both privileged and unprivileged software. When the MPU is enabled, accesses to the System Control Space and vector table are always permitted. Other areas are accessible based on regions and whether PRIVDEFEN is set. Unless HFNMIENA is set, the MPU is not enabled when the processor is executing the handler for an exception with priority –1 or –2. These priorities are only possible when handling a hard fault or NMI exception or when FAULTMASK is enabled. Setting the HFNMIENA bit enables the MPU when operating with these two priorities. MPU Control (MPUCTRL) Base 0xE000.E000 Offset 0xD94 Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 8 7 6 5 4 3 2 1 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 reserved Type Reset reserved Type Reset RO 0 Bit/Field Name Type Reset 31:3 reserved RO 0x0000.000 PRIVDEFEN HFNMIENA R/W 0 R/W 0 ENABLE R/W 0 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. July 03, 2014 169 Texas Instruments-Production Data Cortex-M3 Peripherals Bit/Field Name Type Reset 2 PRIVDEFEN R/W 0 Description MPU Default Region This bit enables privileged software access to the default memory map. Value Description 0 If the MPU is enabled, this bit disables use of the default memory map. Any memory access to a location not covered by any enabled region causes a fault. 1 If the MPU is enabled, this bit enables use of the default memory map as a background region for privileged software accesses. When this bit is set, the background region acts as if it is region number -1. Any region that is defined and enabled has priority over this default map. If the MPU is disabled, the processor ignores this bit. 1 HFNMIENA R/W 0 MPU Enabled During Faults This bit controls the operation of the MPU during hard fault, NMI, and FAULTMASK handlers. Value Description 0 The MPU is disabled during hard fault, NMI, and FAULTMASK handlers, regardless of the value of the ENABLE bit. 1 The MPU is enabled during hard fault, NMI, and FAULTMASK handlers. When the MPU is disabled and this bit is set, the resulting behavior is unpredictable. 0 ENABLE R/W 0 MPU Enable Value Description 0 The MPU is disabled. 1 The MPU is enabled. When the MPU is disabled and the HFNMIENA bit is set, the resulting behavior is unpredictable. 170 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 46: MPU Region Number (MPUNUMBER), offset 0xD98 Note: This register can only be accessed from privileged mode. The MPUNUMBER register selects which memory region is referenced by the MPU Region Base Address (MPUBASE) and MPU Region Attribute and Size (MPUATTR) registers. Normally, the required region number should be written to this register before accessing the MPUBASE or the MPUATTR register. However, the region number can be changed by writing to the MPUBASE register with the VALID bit set (see page 172). This write updates the value of the REGION field. MPU Region Number (MPUNUMBER) Base 0xE000.E000 Offset 0xD98 Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 RO 0 RO 0 1 0 reserved Type Reset RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 9 8 7 6 5 4 3 2 reserved Type Reset RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 Bit/Field Name Type Reset 31:3 reserved RO 0x0000.000 2:0 NUMBER R/W 0x0 NUMBER RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 R/W 0 R/W 0 R/W 0 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. MPU Region to Access This field indicates the MPU region referenced by the MPUBASE and MPUATTR registers. The MPU supports eight memory regions. July 03, 2014 171 Texas Instruments-Production Data Cortex-M3 Peripherals Register 47: MPU Region Base Address (MPUBASE), offset 0xD9C Register 48: MPU Region Base Address Alias 1 (MPUBASE1), offset 0xDA4 Register 49: MPU Region Base Address Alias 2 (MPUBASE2), offset 0xDAC Register 50: MPU Region Base Address Alias 3 (MPUBASE3), offset 0xDB4 Note: This register can only be accessed from privileged mode. The MPUBASE register defines the base address of the MPU region selected by the MPU Region Number (MPUNUMBER) register and can update the value of the MPUNUMBER register. To change the current region number and update the MPUNUMBER register, write the MPUBASE register with the VALID bit set. The ADDR field is bits 31:N of the MPUBASE register. Bits (N-1):5 are reserved. The region size, as specified by the SIZE field in the MPU Region Attribute and Size (MPUATTR) register, defines the value of N where: N = Log2(Region size in bytes) If the region size is configured to 4 GB in the MPUATTR register, there is no valid ADDR field. In this case, the region occupies the complete memory map, and the base address is 0x0000.0000. The base address is aligned to the size of the region. For example, a 64-KB region must be aligned on a multiple of 64 KB, for example, at 0x0001.0000 or 0x0002.0000. MPU Region Base Address (MPUBASE) Base 0xE000.E000 Offset 0xD9C Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 VALID reserved R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 WO 0 RO 0 ADDR Type Reset ADDR Type Reset R/W 0 Bit/Field Name Type Reset 31:5 ADDR R/W 0x0000.000 REGION R/W 0 R/W 0 R/W 0 Description Base Address Mask Bits 31:N in this field contain the region base address. The value of N depends on the region size, as shown above. The remaining bits (N-1):5 are reserved. Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 172 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Bit/Field Name Type Reset 4 VALID WO 0 Description Region Number Valid Value Description 0 The MPUNUMBER register is not changed and the processor updates the base address for the region specified in the MPUNUMBER register and ignores the value of the REGION field. 1 The MPUNUMBER register is updated with the value of the REGION field and the base address is updated for the region specified in the REGION field. This bit is always read as 0. 3 reserved RO 0 2:0 REGION R/W 0x0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. Region Number On a write, contains the value to be written to the MPUNUMBER register. On a read, returns the current region number in the MPUNUMBER register. July 03, 2014 173 Texas Instruments-Production Data Cortex-M3 Peripherals Register 51: MPU Region Attribute and Size (MPUATTR), offset 0xDA0 Register 52: MPU Region Attribute and Size Alias 1 (MPUATTR1), offset 0xDA8 Register 53: MPU Region Attribute and Size Alias 2 (MPUATTR2), offset 0xDB0 Register 54: MPU Region Attribute and Size Alias 3 (MPUATTR3), offset 0xDB8 Note: This register can only be accessed from privileged mode. The MPUATTR register defines the region size and memory attributes of the MPU region specified by the MPU Region Number (MPUNUMBER) register and enables that region and any subregions. The MPUATTR register is accessible using word or halfword accesses with the most-significant halfword holding the region attributes and the least-significant halfword holds the region size and the region and subregion enable bits. The MPU access permission attribute bits, XN, AP, TEX, S, C, and B, control access to the corresponding memory region. If an access is made to an area of memory without the required permissions, then the MPU generates a permission fault. The SIZE field defines the size of the MPU memory region specified by the MPUNUMBER register as follows: (Region size in bytes) = 2(SIZE+1) The smallest permitted region size is 32 bytes, corresponding to a SIZE value of 4. Table 3-9 on page 174 gives example SIZE values with the corresponding region size and value of N in the MPU Region Base Address (MPUBASE) register. Table 3-9. Example SIZE Field Values a SIZE Encoding Region Size Value of N Note 00100b (0x4) 32 B 5 Minimum permitted size 01001b (0x9) 1 KB 10 - 10011b (0x13) 1 MB 20 - 11101b (0x1D) 1 GB 30 - 11111b (0x1F) 4 GB No valid ADDR field in MPUBASE; the Maximum possible size region occupies the complete memory map. a. Refers to the N parameter in the MPUBASE register (see page 172). MPU Region Attribute and Size (MPUATTR) Base 0xE000.E000 Offset 0xDA0 Type R/W, reset 0x0000.0000 31 30 29 28 27 reserved Type Reset 26 25 24 23 AP 21 reserved 20 19 18 TEX 17 16 XN reserved S C B RO 0 RO 0 RO 0 R/W 0 RO 0 R/W 0 R/W 0 R/W 0 RO 0 RO 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 RO 0 RO 0 R/W 0 R/W 0 R/W 0 R/W 0 SRD Type Reset 22 reserved SIZE 174 R/W 0 ENABLE R/W 0 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Bit/Field Name Type Reset Description 31:29 reserved RO 0x00 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 28 XN R/W 0 Instruction Access Disable Value Description 0 Instruction fetches are enabled. 1 Instruction fetches are disabled. 27 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 26:24 AP R/W 0 Access Privilege For information on using this bit field, see Table 3-5 on page 118. 23:22 reserved RO 0x0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 21:19 TEX R/W 0x0 Type Extension Mask For information on using this bit field, see Table 3-3 on page 117. 18 S R/W 0 Shareable For information on using this bit, see Table 3-3 on page 117. 17 C R/W 0 Cacheable For information on using this bit, see Table 3-3 on page 117. 16 B R/W 0 Bufferable For information on using this bit, see Table 3-3 on page 117. 15:8 SRD R/W 0x00 Subregion Disable Bits Value Description 0 The corresponding subregion is enabled. 1 The corresponding subregion is disabled. Region sizes of 128 bytes and less do not support subregions. When writing the attributes for such a region, configure the SRD field as 0x00. See the section called “Subregions” on page 116 for more information. 7:6 reserved RO 0x0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 5:1 SIZE R/W 0x0 Region Size Mask The SIZE field defines the size of the MPU memory region specified by the MPUNUMBER register. Refer to Table 3-9 on page 174 for more information. July 03, 2014 175 Texas Instruments-Production Data Cortex-M3 Peripherals Bit/Field Name Type Reset 0 ENABLE R/W 0 Description Region Enable Value Description 0 The region is disabled. 1 The region is enabled. 176 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller 4 JTAG Interface The Joint Test Action Group (JTAG) port is an IEEE standard that defines a Test Access Port and Boundary Scan Architecture for digital integrated circuits and provides a standardized serial interface for controlling the associated test logic. The TAP, Instruction Register (IR), and Data Registers (DR) can be used to test the interconnections of assembled printed circuit boards and obtain manufacturing information on the components. The JTAG Port also provides a means of accessing and controlling design-for-test features such as I/O pin observation and control, scan testing, and debugging. The JTAG port is comprised of four pins: TCK, TMS, TDI, and TDO. Data is transmitted serially into the controller on TDI and out of the controller on TDO. The interpretation of this data is dependent on the current state of the TAP controller. For detailed information on the operation of the JTAG port and TAP controller, please refer to the IEEE Standard 1149.1-Test Access Port and Boundary-Scan Architecture. ® The Stellaris JTAG controller works with the ARM JTAG controller built into the Cortex-M3 core by multiplexing the TDO outputs from both JTAG controllers. ARM JTAG instructions select the ARM TDO output while Stellaris JTAG instructions select the Stellaris TDO output. The multiplexer is controlled by the Stellaris JTAG controller, which has comprehensive programming for the ARM, Stellaris, and unimplemented JTAG instructions. The Stellaris JTAG module has the following features: ■ IEEE 1149.1-1990 compatible Test Access Port (TAP) controller ■ Four-bit Instruction Register (IR) chain for storing JTAG instructions ■ IEEE standard instructions: BYPASS, IDCODE, SAMPLE/PRELOAD, EXTEST and INTEST ■ ARM additional instructions: APACC, DPACC and ABORT ■ Integrated ARM Serial Wire Debug (SWD) – Serial Wire JTAG Debug Port (SWJ-DP) – Flash Patch and Breakpoint (FPB) unit for implementing breakpoints – Data Watchpoint and Trace (DWT) unit for implementing watchpoints, trigger resources, and system profiling – Instrumentation Trace Macrocell (ITM) for support of printf style debugging – Trace Port Interface Unit (TPIU) for bridging to a Trace Port Analyzer See the ARM® Debug Interface V5 Architecture Specification for more information on the ARM JTAG controller. July 03, 2014 177 Texas Instruments-Production Data JTAG Interface 4.1 Block Diagram Figure 4-1. JTAG Module Block Diagram TCK TMS TAP Controller TDI Instruction Register (IR) BYPASS Data Register TDO Boundary Scan Data Register IDCODE Data Register ABORT Data Register DPACC Data Register APACC Data Register Cortex-M3 Debug Port 4.2 Signal Description The following table lists the external signals of the JTAG/SWD controller and describes the function of each. The JTAG/SWD controller signals are alternate functions for some GPIO signals, however note that the reset state of the pins is for the JTAG/SWD function. The JTAG/SWD controller signals are under commit protection and require a special process to be configured as GPIOs, see “Commit Control” on page 435. The column in the table below titled "Pin Mux/Pin Assignment" lists the GPIO pin placement for the JTAG/SWD controller signals. The AFSEL bit in the GPIO Alternate Function Select (GPIOAFSEL) register (page 450) is set to choose the JTAG/SWD function. The number in parentheses is the encoding that must be programmed into the PMCn field in the GPIO Port Control (GPIOPCTL) register (page 468) to assign the JTAG/SWD controller signals to the specified GPIO port pin. For more information on configuring GPIOs, see “General-Purpose Input/Outputs (GPIOs)” on page 427. Table 4-1. JTAG_SWD_SWO Signals (100LQFP) Pin Name Pin Number Pin Mux / Pin Assignment a Pin Type Buffer Type Description SWCLK 80 PC0 (3) I TTL JTAG/SWD CLK. SWDIO 79 PC1 (3) I/O TTL JTAG TMS and SWDIO. SWO 77 PC3 (3) O TTL JTAG TDO and SWO. TCK 80 PC0 (3) I TTL JTAG/SWD CLK. TDI 78 PC2 (3) I TTL JTAG TDI. TDO 77 PC3 (3) O TTL JTAG TDO and SWO. 178 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Table 4-1. JTAG_SWD_SWO Signals (100LQFP) (continued) Pin Name Pin Number Pin Mux / Pin Assignment 79 TMS a Pin Type Buffer Type I TTL PC1 (3) Description JTAG TMS and SWDIO. a. The TTL designation indicates the pin has TTL-compatible voltage levels. Table 4-2. JTAG_SWD_SWO Signals (108BGA) Pin Name Pin Number Pin Mux / Pin Assignment a Pin Type Buffer Type Description A9 PC0 (3) I TTL JTAG/SWD CLK. SWDIO B9 PC1 (3) I/O TTL JTAG TMS and SWDIO. SWO A10 PC3 (3) O TTL JTAG TDO and SWO. TCK A9 PC0 (3) I TTL JTAG/SWD CLK. SWCLK TDI B8 PC2 (3) I TTL JTAG TDI. TDO A10 PC3 (3) O TTL JTAG TDO and SWO. TMS B9 PC1 (3) I TTL JTAG TMS and SWDIO. a. The TTL designation indicates the pin has TTL-compatible voltage levels. 4.3 Functional Description A high-level conceptual drawing of the JTAG module is shown in Figure 4-1 on page 178. The JTAG module is composed of the Test Access Port (TAP) controller and serial shift chains with parallel update registers. The TAP controller is a simple state machine controlled by the TCK and TMS inputs. The current state of the TAP controller depends on the sequence of values captured on TMS at the rising edge of TCK. The TAP controller determines when the serial shift chains capture new data, shift data from TDI towards TDO, and update the parallel load registers. The current state of the TAP controller also determines whether the Instruction Register (IR) chain or one of the Data Register (DR) chains is being accessed. The serial shift chains with parallel load registers are comprised of a single Instruction Register (IR) chain and multiple Data Register (DR) chains. The current instruction loaded in the parallel load register determines which DR chain is captured, shifted, or updated during the sequencing of the TAP controller. Some instructions, like EXTEST and INTEST, operate on data currently in a DR chain and do not capture, shift, or update any of the chains. Instructions that are not implemented decode to the BYPASS instruction to ensure that the serial path between TDI and TDO is always connected (see Table 4-4 on page 185 for a list of implemented instructions). See “JTAG and Boundary Scan” on page 1223 for JTAG timing diagrams. Note: 4.3.1 Of all the possible reset sources, only Power-On reset (POR) and the assertion of the RST input have any effect on the JTAG module. The pin configurations are reset by both the RST input and POR, whereas the internal JTAG logic is only reset with POR. See “Reset Sources” on page 190 for more information on reset. JTAG Interface Pins The JTAG interface consists of four standard pins: TCK, TMS, TDI, and TDO. These pins and their associated state after a power-on reset or reset caused by the RST input are given in Table 4-3. Detailed information on each pin follows. Refer to “General-Purpose Input/Outputs (GPIOs)” on page 427 for information on how to reprogram the configuration of these pins. July 03, 2014 179 Texas Instruments-Production Data JTAG Interface Table 4-3. JTAG Port Pins State after Power-On Reset or RST assertion 4.3.1.1 Pin Name Data Direction Internal Pull-Up Internal Pull-Down Drive Strength Drive Value TCK Input Enabled Disabled N/A N/A TMS Input Enabled Disabled N/A N/A TDI Input Enabled Disabled N/A N/A TDO Output Enabled Disabled 2-mA driver High-Z Test Clock Input (TCK) The TCK pin is the clock for the JTAG module. This clock is provided so the test logic can operate independently of any other system clocks and to ensure that multiple JTAG TAP controllers that are daisy-chained together can synchronously communicate serial test data between components. During normal operation, TCK is driven by a free-running clock with a nominal 50% duty cycle. When necessary, TCK can be stopped at 0 or 1 for extended periods of time. While TCK is stopped at 0 or 1, the state of the TAP controller does not change and data in the JTAG Instruction and Data Registers is not lost. By default, the internal pull-up resistor on the TCK pin is enabled after reset, assuring that no clocking occurs if the pin is not driven from an external source. The internal pull-up and pull-down resistors can be turned off to save internal power as long as the TCK pin is constantly being driven by an external source (see page 456 and page 458). 4.3.1.2 Test Mode Select (TMS) The TMS pin selects the next state of the JTAG TAP controller. TMS is sampled on the rising edge of TCK. Depending on the current TAP state and the sampled value of TMS, the next state may be entered. Because the TMS pin is sampled on the rising edge of TCK, the IEEE Standard 1149.1 expects the value on TMS to change on the falling edge of TCK. Holding TMS high for five consecutive TCK cycles drives the TAP controller state machine to the Test-Logic-Reset state. When the TAP controller enters the Test-Logic-Reset state, the JTAG module and associated registers are reset to their default values. This procedure should be performed to initialize the JTAG controller. The JTAG Test Access Port state machine can be seen in its entirety in Figure 4-2 on page 181. By default, the internal pull-up resistor on the TMS pin is enabled after reset. Changes to the pull-up resistor settings on GPIO Port C should ensure that the internal pull-up resistor remains enabled on PC1/TMS; otherwise JTAG communication could be lost (see page 456). 4.3.1.3 Test Data Input (TDI) The TDI pin provides a stream of serial information to the IR chain and the DR chains. TDI is sampled on the rising edge of TCK and, depending on the current TAP state and the current instruction, may present this data to the proper shift register chain. Because the TDI pin is sampled on the rising edge of TCK, the IEEE Standard 1149.1 expects the value on TDI to change on the falling edge of TCK. By default, the internal pull-up resistor on the TDI pin is enabled after reset. Changes to the pull-up resistor settings on GPIO Port C should ensure that the internal pull-up resistor remains enabled on PC2/TDI; otherwise JTAG communication could be lost (see page 456). 4.3.1.4 Test Data Output (TDO) The TDO pin provides an output stream of serial information from the IR chain or the DR chains. The value of TDO depends on the current TAP state, the current instruction, and the data in the 180 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller chain being accessed. In order to save power when the JTAG port is not being used, the TDO pin is placed in an inactive drive state when not actively shifting out data. Because TDO can be connected to the TDI of another controller in a daisy-chain configuration, the IEEE Standard 1149.1 expects the value on TDO to change on the falling edge of TCK. By default, the internal pull-up resistor on the TDO pin is enabled after reset, assuring that the pin remains at a constant logic level when the JTAG port is not being used. The internal pull-up and pull-down resistors can be turned off to save internal power if a High-Z output value is acceptable during certain TAP controller states (see page 456 and page 458). 4.3.2 JTAG TAP Controller The JTAG TAP controller state machine is shown in Figure 4-2. The TAP controller state machine is reset to the Test-Logic-Reset state on the assertion of a Power-On-Reset (POR). In order to reset the JTAG module after the microcontroller has been powered on, the TMS input must be held HIGH for five TCK clock cycles, resetting the TAP controller and all associated JTAG chains. Asserting the correct sequence on the TMS pin allows the JTAG module to shift in new instructions, shift in data, or idle during extended testing sequences. For detailed information on the function of the TAP controller and the operations that occur in each state, please refer to IEEE Standard 1149.1. Figure 4-2. Test Access Port State Machine Test Logic Reset 1 0 Run Test Idle 0 Select DR Scan 1 Select IR Scan 1 0 1 Capture DR 1 Capture IR 0 0 Shift DR Shift IR 0 1 Exit 1 DR Exit 1 IR 1 Pause IR 0 1 Exit 2 DR 0 1 0 Exit 2 IR 1 1 Update DR 4.3.3 1 0 Pause DR 1 0 1 0 0 1 0 0 Update IR 1 0 Shift Registers The Shift Registers consist of a serial shift register chain and a parallel load register. The serial shift register chain samples specific information during the TAP controller’s CAPTURE states and allows July 03, 2014 181 Texas Instruments-Production Data JTAG Interface this information to be shifted out on TDO during the TAP controller’s SHIFT states. While the sampled data is being shifted out of the chain on TDO, new data is being shifted into the serial shift register on TDI. This new data is stored in the parallel load register during the TAP controller’s UPDATE states. Each of the shift registers is discussed in detail in “Register Descriptions” on page 185. 4.3.4 Operational Considerations Certain operational parameters must be considered when using the JTAG module. Because the JTAG pins can be programmed to be GPIOs, board configuration and reset conditions on these pins must be considered. In addition, because the JTAG module has integrated ARM Serial Wire Debug, the method for switching between these two operational modes is described below. 4.3.4.1 GPIO Functionality When the microcontroller is reset with either a POR or RST, the JTAG/SWD port pins default to their JTAG/SWD configurations. The default configuration includes enabling digital functionality (DEN[3:0] set in the Port C GPIO Digital Enable (GPIODEN) register), enabling the pull-up resistors (PUE[3:0] set in the Port C GPIO Pull-Up Select (GPIOPUR) register), disabling the pull-down resistors (PDE[3:0] cleared in the Port C GPIO Pull-Down Select (GPIOPDR) register) and enabling the alternate hardware function (AFSEL[3:0] set in the Port C GPIO Alternate Function Select (GPIOAFSEL) register) on the JTAG/SWD pins. See page 450, page 456, page 458, and page 461. It is possible for software to configure these pins as GPIOs after reset by clearing AFSEL[3:0] in the Port C GPIOAFSEL register. If the user does not require the JTAG/SWD port for debugging or board-level testing, this provides four more GPIOs for use in the design. Caution – It is possible to create a software sequence that prevents the debugger from connecting to the Stellaris microcontroller. If the program code loaded into flash immediately changes the JTAG pins to their GPIO functionality, the debugger may not have enough time to connect and halt the controller before the JTAG pin functionality switches. As a result, the debugger may be locked out of the part. This issue can be avoided with a software routine that restores JTAG functionality based on an external or software trigger. The GPIO commit control registers provide a layer of protection against accidental programming of critical hardware peripherals. Protection is provided for the NMI pin (PB7) and the four JTAG/SWD pins (PC[3:0]). Writes to protected bits of the GPIO Alternate Function Select (GPIOAFSEL) register (see page 450), GPIO Pull Up Select (GPIOPUR) register (see page 456), GPIO Pull-Down Select (GPIOPDR) register (see page 458), and GPIO Digital Enable (GPIODEN) register (see page 461) are not committed to storage unless the GPIO Lock (GPIOLOCK) register (see page 463) has been unlocked and the appropriate bits of the GPIO Commit (GPIOCR) register (see page 464) have been set. 4.3.4.2 Communication with JTAG/SWD Because the debug clock and the system clock can be running at different frequencies, care must be taken to maintain reliable communication with the JTAG/SWD interface. In the Capture-DR state, the result of the previous transaction, if any, is returned, together with a 3-bit ACK response. Software should check the ACK response to see if the previous operation has completed before initiating a new transaction. Alternatively, if the system clock is at least 8 times faster than the debug clock (TCK or SWCLK), the previous operation has enough time to complete and the ACK bits do not have to be checked. 182 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller 4.3.4.3 Recovering a "Locked" Microcontroller Note: Performing the sequence below restores the non-volatile registers discussed in “Non-Volatile Register Programming” on page 327 to their factory default values. The mass erase of the Flash memory caused by the sequence below occurs prior to the non-volatile registers being restored. If software configures any of the JTAG/SWD pins as GPIO and loses the ability to communicate with the debugger, there is a debug port unlock sequence that can be used to recover the microcontroller. Performing a total of ten JTAG-to-SWD and SWD-to-JTAG switch sequences while holding the microcontroller in reset mass erases the Flash memory. The debug port unlock sequence is: 1. Assert and hold the RST signal. 2. Apply power to the device. 3. Perform steps 1 and 2 of the JTAG-to-SWD switch sequence on the section called “JTAG-to-SWD Switching” on page 184. 4. Perform steps 1 and 2 of the SWD-to-JTAG switch sequence on the section called “SWD-to-JTAG Switching” on page 184. 5. Perform steps 1 and 2 of the JTAG-to-SWD switch sequence. 6. Perform steps 1 and 2 of the SWD-to-JTAG switch sequence. 7. Perform steps 1 and 2 of the JTAG-to-SWD switch sequence. 8. Perform steps 1 and 2 of the SWD-to-JTAG switch sequence. 9. Perform steps 1 and 2 of the JTAG-to-SWD switch sequence. 10. Perform steps 1 and 2 of the SWD-to-JTAG switch sequence. 11. Perform steps 1 and 2 of the JTAG-to-SWD switch sequence. 12. Perform steps 1 and 2 of the SWD-to-JTAG switch sequence. 13. Release the RST signal. 14. Wait 400 ms. 15. Power-cycle the microcontroller. 4.3.4.4 ARM Serial Wire Debug (SWD) In order to seamlessly integrate the ARM Serial Wire Debug (SWD) functionality, a serial-wire debugger must be able to connect to the Cortex-M3 core without having to perform, or have any knowledge of, JTAG cycles. This integration is accomplished with a SWD preamble that is issued before the SWD session begins. The switching preamble used to enable the SWD interface of the SWJ-DP module starts with the TAP controller in the Test-Logic-Reset state. From here, the preamble sequences the TAP controller through the following states: Run Test Idle, Select DR, Select IR, Test Logic Reset, Test Logic Reset, Run Test Idle, Run Test Idle, Select DR, Select IR, Test Logic Reset, Test Logic Reset, Run Test Idle, Run Test Idle, Select DR, Select IR, and Test Logic Reset states. July 03, 2014 183 Texas Instruments-Production Data JTAG Interface Stepping through this sequence of the TAP state machine enables the SWD interface and disables the JTAG interface. For more information on this operation and the SWD interface, see the ARM® Debug Interface V5 Architecture Specification. Because this sequence is a valid series of JTAG operations that could be issued, the ARM JTAG TAP controller is not fully compliant to the IEEE Standard 1149.1. This instance is the only one where the ARM JTAG TAP controller does not meet full compliance with the specification. Due to the low probability of this sequence occurring during normal operation of the TAP controller, it should not affect normal performance of the JTAG interface. JTAG-to-SWD Switching To switch the operating mode of the Debug Access Port (DAP) from JTAG to SWD mode, the external debug hardware must send the switching preamble to the microcontroller. The 16-bit TMS/SWDIO command for switching to SWD mode is defined as b1110.0111.1001.1110, transmitted LSB first. This command can also be represented as 0xE79E when transmitted LSB first. The complete switch sequence should consist of the following transactions on the TCK/SWCLK and TMS/SWDIO signals: 1. Send at least 50 TCK/SWCLK cycles with TMS/SWDIO High to ensure that both JTAG and SWD are in their reset states. 2. Send the 16-bit JTAG-to-SWD switch command, 0xE79E, on TMS/SWDIO. 3. Send at least 50 TCK/SWCLK cycles with TMS/SWDIO High to ensure that if SWJ-DP was already in SWD mode before sending the switch sequence, the SWD goes into the line reset state. To verify that the Debug Access Port (DAP) has switched to the Serial Wire Debug (SWD) operating mode, perform a SWD READID operation. The ID value can be compared against the device's known ID to verify the switch. SWD-to-JTAG Switching To switch the operating mode of the Debug Access Port (DAP) from SWD to JTAG mode, the external debug hardware must send a switch command to the microcontroller. The 16-bit TMS/SWDIO command for switching to JTAG mode is defined as b1110.0111.0011.1100, transmitted LSB first. This command can also be represented as 0xE73C when transmitted LSB first. The complete switch sequence should consist of the following transactions on the TCK/SWCLK and TMS/SWDIO signals: 1. Send at least 50 TCK/SWCLK cycles with TMS/SWDIO High to ensure that both JTAG and SWD are in their reset states. 2. Send the 16-bit SWD-to-JTAG switch command, 0xE73C, on TMS/SWDIO. 3. Send at least 50 TCK/SWCLK cycles with TMS/SWDIO High to ensure that if SWJ-DP was already in JTAG mode before sending the switch sequence, the JTAG goes into the Test Logic Reset state. To verify that the Debug Access Port (DAP) has switched to the JTAG operating mode, set the JTAG Instruction Register (IR) to the IDCODE instruction and shift out the Data Register (DR). The DR value can be compared against the device's known IDCODE to verify the switch. 4.4 Initialization and Configuration After a Power-On-Reset or an external reset (RST), the JTAG pins are automatically configured for JTAG communication. No user-defined initialization or configuration is needed. However, if the user 184 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller application changes these pins to their GPIO function, they must be configured back to their JTAG functionality before JTAG communication can be restored. To return the pins to their JTAG functions, enable the four JTAG pins (PC[3:0]) for their alternate function using the GPIOAFSEL register. In addition to enabling the alternate functions, any other changes to the GPIO pad configurations on the four JTAG pins (PC[3:0]) should be returned to their default settings. 4.5 Register Descriptions The registers in the JTAG TAP Controller or Shift Register chains are not memory mapped and are not accessible through the on-chip Advanced Peripheral Bus (APB). Instead, the registers within the JTAG controller are all accessed serially through the TAP Controller. These registers include the Instruction Register and the six Data Registers. 4.5.1 Instruction Register (IR) The JTAG TAP Instruction Register (IR) is a four-bit serial scan chain connected between the JTAG TDI and TDO pins with a parallel load register. When the TAP Controller is placed in the correct states, bits can be shifted into the IR. Once these bits have been shifted into the chain and updated, they are interpreted as the current instruction. The decode of the IR bits is shown in Table 4-4. A detailed explanation of each instruction, along with its associated Data Register, follows. Table 4-4. JTAG Instruction Register Commands 4.5.1.1 IR[3:0] Instruction Description 0x0 EXTEST Drives the values preloaded into the Boundary Scan Chain by the SAMPLE/PRELOAD instruction onto the pads. 0x1 INTEST Drives the values preloaded into the Boundary Scan Chain by the SAMPLE/PRELOAD instruction into the controller. 0x2 SAMPLE / PRELOAD Captures the current I/O values and shifts the sampled values out of the Boundary Scan Chain while new preload data is shifted in. 0x8 ABORT Shifts data into the ARM Debug Port Abort Register. 0xA DPACC Shifts data into and out of the ARM DP Access Register. 0xB APACC Shifts data into and out of the ARM AC Access Register. 0xE IDCODE Loads manufacturing information defined by the IEEE Standard 1149.1 into the IDCODE chain and shifts it out. 0xF BYPASS Connects TDI to TDO through a single Shift Register chain. All Others Reserved Defaults to the BYPASS instruction to ensure that TDI is always connected to TDO. EXTEST Instruction The EXTEST instruction is not associated with its own Data Register chain. Instead, the EXTEST instruction uses the data that has been preloaded into the Boundary Scan Data Register using the SAMPLE/PRELOAD instruction. When the EXTEST instruction is present in the Instruction Register, the preloaded data in the Boundary Scan Data Register associated with the outputs and output enables are used to drive the GPIO pads rather than the signals coming from the core. With tests that drive known values out of the controller, this instruction can be used to verify connectivity. While the EXTEST instruction is present in the Instruction Register, the Boundary Scan Data Register can be accessed to sample and shift out the current data and load new data into the Boundary Scan Data Register. July 03, 2014 185 Texas Instruments-Production Data JTAG Interface 4.5.1.2 INTEST Instruction The INTEST instruction is not associated with its own Data Register chain. Instead, the INTEST instruction uses the data that has been preloaded into the Boundary Scan Data Register using the SAMPLE/PRELOAD instruction. When the INTEST instruction is present in the Instruction Register, the preloaded data in the Boundary Scan Data Register associated with the inputs are used to drive the signals going into the core rather than the signals coming from the GPIO pads. With tests that drive known values into the controller, this instruction can be used for testing. It is important to note that although the RST input pin is on the Boundary Scan Data Register chain, it is only observable. While the INTEST instruction is present in the Instruction Register, the Boundary Scan Data Register can be accessed to sample and shift out the current data and load new data into the Boundary Scan Data Register. 4.5.1.3 SAMPLE/PRELOAD Instruction The SAMPLE/PRELOAD instruction connects the Boundary Scan Data Register chain between TDI and TDO. This instruction samples the current state of the pad pins for observation and preloads new test data. Each GPIO pad has an associated input, output, and output enable signal. When the TAP controller enters the Capture DR state during this instruction, the input, output, and output-enable signals to each of the GPIO pads are captured. These samples are serially shifted out on TDO while the TAP controller is in the Shift DR state and can be used for observation or comparison in various tests. While these samples of the inputs, outputs, and output enables are being shifted out of the Boundary Scan Data Register, new data is being shifted into the Boundary Scan Data Register from TDI. Once the new data has been shifted into the Boundary Scan Data Register, the data is saved in the parallel load registers when the TAP controller enters the Update DR state. This update of the parallel load register preloads data into the Boundary Scan Data Register that is associated with each input, output, and output enable. This preloaded data can be used with the EXTEST and INTEST instructions to drive data into or out of the controller. See “Boundary Scan Data Register” on page 188 for more information. 4.5.1.4 ABORT Instruction The ABORT instruction connects the associated ABORT Data Register chain between TDI and TDO. This instruction provides read and write access to the ABORT Register of the ARM Debug Access Port (DAP). Shifting the proper data into this Data Register clears various error bits or initiates a DAP abort of a previous request. See the “ABORT Data Register” on page 188 for more information. 4.5.1.5 DPACC Instruction The DPACC instruction connects the associated DPACC Data Register chain between TDI and TDO. This instruction provides read and write access to the DPACC Register of the ARM Debug Access Port (DAP). Shifting the proper data into this register and reading the data output from this register allows read and write access to the ARM debug and status registers. See “DPACC Data Register” on page 188 for more information. 4.5.1.6 APACC Instruction The APACC instruction connects the associated APACC Data Register chain between TDI and TDO. This instruction provides read and write access to the APACC Register of the ARM Debug Access Port (DAP). Shifting the proper data into this register and reading the data output from this register allows read and write access to internal components and buses through the Debug Port. See “APACC Data Register” on page 188 for more information. 186 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller 4.5.1.7 IDCODE Instruction The IDCODE instruction connects the associated IDCODE Data Register chain between TDI and TDO. This instruction provides information on the manufacturer, part number, and version of the ARM core. This information can be used by testing equipment and debuggers to automatically configure input and output data streams. IDCODE is the default instruction loaded into the JTAG Instruction Register when a Power-On-Reset (POR) is asserted, or the Test-Logic-Reset state is entered. See “IDCODE Data Register” on page 187 for more information. 4.5.1.8 BYPASS Instruction The BYPASS instruction connects the associated BYPASS Data Register chain between TDI and TDO. This instruction is used to create a minimum length serial path between the TDI and TDO ports. The BYPASS Data Register is a single-bit shift register. This instruction improves test efficiency by allowing components that are not needed for a specific test to be bypassed in the JTAG scan chain by loading them with the BYPASS instruction. See “BYPASS Data Register” on page 187 for more information. 4.5.2 Data Registers The JTAG module contains six Data Registers. These serial Data Register chains include: IDCODE, BYPASS, Boundary Scan, APACC, DPACC, and ABORT and are discussed in the following sections. 4.5.2.1 IDCODE Data Register The format for the 32-bit IDCODE Data Register defined by the IEEE Standard 1149.1 is shown in Figure 4-3. The standard requires that every JTAG-compliant microcontroller implement either the IDCODE instruction or the BYPASS instruction as the default instruction. The LSB of the IDCODE Data Register is defined to be a 1 to distinguish it from the BYPASS instruction, which has an LSB of 0. This definition allows auto-configuration test tools to determine which instruction is the default instruction. The major uses of the JTAG port are for manufacturer testing of component assembly and program development and debug. To facilitate the use of auto-configuration debug tools, the IDCODE instruction outputs a value of 0x4BA0.0477. This value allows the debuggers to automatically configure themselves to work correctly with the Cortex-M3 during debug. Figure 4-3. IDCODE Register Format 31 TDI 4.5.2.2 28 27 12 11 Version Part Number 1 0 Manufacturer ID 1 TDO BYPASS Data Register The format for the 1-bit BYPASS Data Register defined by the IEEE Standard 1149.1 is shown in Figure 4-4. The standard requires that every JTAG-compliant microcontroller implement either the BYPASS instruction or the IDCODE instruction as the default instruction. The LSB of the BYPASS Data Register is defined to be a 0 to distinguish it from the IDCODE instruction, which has an LSB of 1. This definition allows auto-configuration test tools to determine which instruction is the default instruction. July 03, 2014 187 Texas Instruments-Production Data JTAG Interface Figure 4-4. BYPASS Register Format 0 0 TDI 4.5.2.3 TDO Boundary Scan Data Register The format of the Boundary Scan Data Register is shown in Figure 4-5. Each GPIO pin, starting with a GPIO pin next to the JTAG port pins, is included in the Boundary Scan Data Register. Each GPIO pin has three associated digital signals that are included in the chain. These signals are input, output, and output enable, and are arranged in that order as shown in the figure. When the Boundary Scan Data Register is accessed with the SAMPLE/PRELOAD instruction, the input, output, and output enable from each digital pad are sampled and then shifted out of the chain to be verified. The sampling of these values occurs on the rising edge of TCK in the Capture DR state of the TAP controller. While the sampled data is being shifted out of the Boundary Scan chain in the Shift DR state of the TAP controller, new data can be preloaded into the chain for use with the EXTEST and INTEST instructions. The EXTEST instruction forces data out of the controller, and the INTEST instruction forces data into the controller. Figure 4-5. Boundary Scan Register Format TDI I N O U T O E ... 1st GPIO 4.5.2.4 I N O U T mth GPIO O E I N O U T (m+1)th GPIO O E ... I N O U T O E TDO GPIO nth APACC Data Register The format for the 35-bit APACC Data Register defined by ARM is described in the ARM® Debug Interface V5 Architecture Specification. 4.5.2.5 DPACC Data Register The format for the 35-bit DPACC Data Register defined by ARM is described in the ARM® Debug Interface V5 Architecture Specification. 4.5.2.6 ABORT Data Register The format for the 35-bit ABORT Data Register defined by ARM is described in the ARM® Debug Interface V5 Architecture Specification. 188 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller 5 System Control System control configures the overall operation of the device and provides information about the device. Configurable features include reset control, NMI operation, power control, clock control, and low-power modes. 5.1 Signal Description The following table lists the external signals of the System Control module and describes the function of each. The NMI signal is the alternate function for the GPIO PB7 signal and functions as a GPIO after reset. PB7 is under commit protection and requires a special process to be configured as any alternate function or to subsequently return to the GPIO function, see “Commit Control” on page 435. The column in the table below titled "Pin Mux/Pin Assignment" lists the GPIO pin placement for the NMI signal. The AFSEL bit in the GPIO Alternate Function Select (GPIOAFSEL) register (page 450) should be set to choose the NMI function. The number in parentheses is the encoding that must be programmed into the PMCn field in the GPIO Port Control (GPIOPCTL) register (page 468) to assign the NMI signal to the specified GPIO port pin. For more information on configuring GPIOs, see “General-Purpose Input/Outputs (GPIOs)” on page 427. The remaining signals (with the word "fixed" in the Pin Mux/Pin Assignment column) have a fixed pin assignment and function. Table 5-1. System Control & Clocks Signals (100LQFP) Pin Name Pin Number Pin Mux / Pin Assignment a Pin Type Buffer Type Description NMI 89 PB7 (4) I TTL Non-maskable interrupt. OSC0 48 fixed I Analog Main oscillator crystal input or an external clock reference input. OSC1 49 fixed O Analog Main oscillator crystal output. Leave unconnected when using a single-ended clock source. RST 64 fixed I TTL System reset input. a. The TTL designation indicates the pin has TTL-compatible voltage levels. Table 5-2. System Control & Clocks Signals (108BGA) Pin Name Pin Number Pin Mux / Pin Assignment a Pin Type Buffer Type Description NMI A8 PB7 (4) I TTL Non-maskable interrupt. OSC0 L11 fixed I Analog Main oscillator crystal input or an external clock reference input. OSC1 M11 fixed O Analog Main oscillator crystal output. Leave unconnected when using a single-ended clock source. RST H11 fixed I TTL System reset input. a. The TTL designation indicates the pin has TTL-compatible voltage levels. 5.2 Functional Description The System Control module provides the following capabilities: ■ Device identification, see “Device Identification” on page 190 ■ Local control, such as reset (see “Reset Control” on page 190), power (see “Power Control” on page 195) and clock control (see “Clock Control” on page 196) July 03, 2014 189 Texas Instruments-Production Data System Control ■ System control (Run, Sleep, and Deep-Sleep modes), see “System Control” on page 203 5.2.1 Device Identification Several read-only registers provide software with information on the microcontroller, such as version, part number, SRAM size, Flash memory size, and other features. See the DID0 (page 208), DID1 (page 237), DC0-DC9 (page 239) and NVMSTAT (page 259) registers. 5.2.2 Reset Control This section discusses aspects of hardware functions during reset as well as system software requirements following the reset sequence. 5.2.2.1 Reset Sources The LM3S9U90 microcontroller has six sources of reset: 1. Power-on reset (POR) (see page 191). 2. External reset input pin (RST) assertion (see page 191). 3. Internal brown-out (BOR) detector (see page 193). 4. Software-initiated reset (with the software reset registers) (see page 193). 5. A watchdog timer reset condition violation (see page 194). 6. MOSC failure (see page 195). Table 5-3 provides a summary of results of the various reset operations. Table 5-3. Reset Sources Core Reset? JTAG Reset? On-Chip Peripherals Reset? Power-On Reset Reset Source Yes Yes Yes RST Yes Yes Yes Brown-Out Reset Yes Yes Yes Software System Request Reset using the SYSRESREQ bit in the APINT register. Yes Yes Yes Software System Request Reset using the VECTRESET bit in the APINT register. Yes No No Software Peripheral Reset No Yes Yes Watchdog Reset Yes Yes Yes MOSC Failure Reset Yes Yes Yes a a. Programmable on a module-by-module basis using the Software Reset Control Registers. After a reset, the Reset Cause (RESC) register is set with the reset cause. The bits in this register are sticky and maintain their state across multiple reset sequences, except when an internal POR or an external reset is the cause, and then all the other bits in the RESC register are cleared except for the POR or EXT indicator. 190 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller At any reset that resets the core, the user has the opportunity to direct the core to execute the ROM Boot Loader or the application in Flash memory by using any GPIO signal as configured in the Boot Configuration (BOOTCFG) register. At reset, the ROM is mapped over the Flash memory so that the ROM boot sequence is always executed. The boot sequence executed from ROM is as follows: 1. The BA bit (below) is cleared such that ROM is mapped to 0x01xx.xxxx and Flash memory is mapped to address 0x0. 2. The BOOTCFG register is read. If the EN bit is clear, the status of the specified GPIO pin is compared with the specified polarity. If the status matches the specified polarity, the ROM is mapped to address 0x0000.0000 and execution continues out of the ROM Boot Loader. 3. If the status doesn't match the specified polarity, the data at address 0x0000.0004 is read, and if the data at this address is 0xFFFF.FFFF, the ROM is mapped to address 0x0000.0000 and execution continues out of the ROM Boot Loader. 4. If there is valid data at address 0x0000.0004, the stack pointer (SP) is loaded from Flash memory at address 0x0000.0000 and the program counter (PC) is loaded from address 0x0000.0004. The user application begins executing. For example, if the BOOTCFG register is written and committed with the value of 0x0000.3C01, then PB7 is examined at reset to determine if the ROM Boot Loader should be executed. If PB7 is Low, the core unconditionally begins executing the ROM boot loader. If PB7 is High, then the application in Flash memory is executed if the reset vector at location 0x0000.0004 is not 0xFFFF.FFFF. Otherwise, the ROM boot loader is executed. 5.2.2.2 Power-On Reset (POR) The internal Power-On Reset (POR) circuit monitors the power supply voltage (VDD) and generates a reset signal to all of the internal logic including JTAG when the power supply ramp reaches a threshold value (VTH). The microcontroller must be operating within the specified operating parameters when the on-chip power-on reset pulse is complete (see “Power and Brown-Out” on page 1225). For applications that require the use of an external reset signal to hold the microcontroller in reset longer than the internal POR, the RST input may be used as discussed in “External RST Pin” on page 191. The Power-On Reset sequence is as follows: 1. The microcontroller waits for internal POR to go inactive. 2. The internal reset is released and the core loads from memory the initial stack pointer, the initial program counter, and the first instruction designated by the program counter, and then begins execution. The internal POR is only active on the initial power-up of the microcontroller and when the microcontroller wakes from hibernation. The Power-On Reset timing is shown in Figure 25-4 on page 1225. 5.2.2.3 External RST Pin Note: It is recommended that the trace for the RST signal must be kept as short as possible. Be sure to place any components connected to the RST signal as close to the microcontroller as possible. July 03, 2014 191 Texas Instruments-Production Data System Control If the application only uses the internal POR circuit, the RST input must be connected to the power supply (VDD) through an optional pull-up resistor (0 to 100K Ω) as shown in Figure 5-1 on page 192. Figure 5-1. Basic RST Configuration VDD Stellaris® RPU RST RPU = 0 to 100 kΩ The external reset pin (RST) resets the microcontroller including the core and all the on-chip peripherals except the JTAG TAP controller (see “JTAG Interface” on page 177). The external reset sequence is as follows: 1. The external reset pin (RST) is asserted for the duration specified by TMIN and then de-asserted (see “Reset” on page 1226). 2. The internal reset is released and the core loads from memory the initial stack pointer, the initial program counter, and the first instruction designated by the program counter, and then begins execution. To improve noise immunity and/or to delay reset at power up, the RST input may be connected to an RC network as shown in Figure 5-2 on page 192. Figure 5-2. External Circuitry to Extend Power-On Reset VDD Stellaris® RPU RST C1 RPU = 1 kΩ to 100 kΩ C1 = 1 nF to 10 µF If the application requires the use of an external reset switch, Figure 5-3 on page 193 shows the proper circuitry to use. 192 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Figure 5-3. Reset Circuit Controlled by Switch VDD Stellaris® RPU RST C1 RS Typical RPU = 10 kΩ Typical RS = 470 Ω C1 = 10 nF The RPU and C1 components define the power-on delay. The external reset timing is shown in Figure 25-7 on page 1226. 5.2.2.4 Brown-Out Reset (BOR) The microcontroller provides a brown-out detection circuit that triggers if the power supply (VDD) drops below a brown-out threshold voltage (VBTH). If a brown-out condition is detected, the system may generate an interrupt or a system reset. The default condition is to reset the microcontroller. Brown-out resets are controlled with the Power-On and Brown-Out Reset Control (PBORCTL) register. The BORIOR bit in the PBORCTL register must be set for a brown-out condition to trigger a reset; if BORIOR is clear, an interrupt is generated. When a Brown-out condition occurs during a Flash PROGRAM or ERASE operation, a full system reset is always triggered without regard to the setting in the PBORCTL register. The brown-out reset sequence is as follows: 1. When VDD drops below VBTH, an internal BOR condition is set. 2. If the BOR condition exists, an internal reset is asserted. 3. The internal reset is released and the microcontroller fetches and loads the initial stack pointer, the initial program counter, the first instruction designated by the program counter, and begins execution. 4. The internal BOR condition is reset after 500 µs to prevent another BOR condition from being set before software has a chance to investigate the original cause. The result of a brown-out reset is equivalent to that of an assertion of the external RST input, and the reset is held active until the proper VDD level is restored. The RESC register can be examined in the reset interrupt handler to determine if a Brown-Out condition was the cause of the reset, thus allowing software to determine what actions are required to recover. The internal Brown-Out Reset timing is shown in Figure 25-5 on page 1225. 5.2.2.5 Software Reset Software can reset a specific peripheral or generate a reset to the entire microcontroller. July 03, 2014 193 Texas Instruments-Production Data System Control Peripherals can be individually reset by software via three registers that control reset signals to each on-chip peripheral (see the SRCRn registers, page 286). If the bit position corresponding to a peripheral is set and subsequently cleared, the peripheral is reset. The encoding of the reset registers is consistent with the encoding of the clock gating control for peripherals and on-chip functions (see “System Control” on page 203). The entire microcontroller, including the core, can be reset by software by setting the SYSRESREQ bit in the Application Interrupt and Reset Control (APINT) register. The software-initiated system reset sequence is as follows: 1. A software microcontroller reset is initiated by setting the SYSRESREQ bit. 2. An internal reset is asserted. 3. The internal reset is deasserted and the microcontroller loads from memory the initial stack pointer, the initial program counter, and the first instruction designated by the program counter, and then begins execution. The core only can be reset by software by setting the VECTRESET bit in the APINT register. The software-initiated core reset sequence is as follows: 1. A core reset is initiated by setting the VECTRESET bit. 2. An internal reset is asserted. 3. The internal reset is deasserted and the microcontroller loads from memory the initial stack pointer, the initial program counter, and the first instruction designated by the program counter, and then begins execution. The software-initiated system reset timing is shown in Figure 25-8 on page 1226. 5.2.2.6 Watchdog Timer Reset The Watchdog Timer module's function is to prevent system hangs. The LM3S9U90 microcontroller has two Watchdog Timer modules in case one watchdog clock source fails. One watchdog is run off the system clock and the other is run off the Precision Internal Oscillator (PIOSC). Each module operates in the same manner except that because the PIOSC watchdog timer module is in a different clock domain, register accesses must have a time delay between them. The watchdog timer can be configured to generate an interrupt to the microcontroller on its first time-out and to generate a reset on its second time-out. After the watchdog's first time-out event, the 32-bit watchdog counter is reloaded with the value of the Watchdog Timer Load (WDTLOAD) register and resumes counting down from that value. If the timer counts down to zero again before the first time-out interrupt is cleared, and the reset signal has been enabled, the watchdog timer asserts its reset signal to the microcontroller. The watchdog timer reset sequence is as follows: 1. The watchdog timer times out for the second time without being serviced. 2. An internal reset is asserted. 3. The internal reset is released and the microcontroller loads from memory the initial stack pointer, the initial program counter, and the first instruction designated by the program counter, and then begins execution. For more information on the Watchdog Timer module, see “Watchdog Timers” on page 604. 194 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller The watchdog reset timing is shown in Figure 25-9 on page 1227. 5.2.3 Non-Maskable Interrupt The microcontroller has three sources of non-maskable interrupt (NMI): ■ The assertion of the NMI signal ■ A main oscillator verification error ■ The NMISET bit in the Interrupt Control and State (INTCTRL) register in the Cortex™-M3 (see page 142). Software must check the cause of the interrupt in order to distinguish among the sources. 5.2.3.1 NMI Pin The NMI signal is the alternate function for GPIO port pin PB7. The alternate function must be enabled in the GPIO for the signal to be used as an interrupt, as described in “General-Purpose Input/Outputs (GPIOs)” on page 427. Note that enabling the NMI alternate function requires the use of the GPIO lock and commit function just like the GPIO port pins associated with JTAG/SWD functionality, see page 464. The active sense of the NMI signal is High; asserting the enabled NMI signal above VIH initiates the NMI interrupt sequence. 5.2.3.2 Main Oscillator Verification Failure The LM3S9U90 microcontroller provides a main oscillator verification circuit that generates an error condition if the oscillator is running too fast or too slow. If the main oscillator verification circuit is enabled and a failure occurs, a power-on reset is generated and control is transferred to the NMI handler. The NMI handler is used to address the main oscillator verification failure because the necessary code can be removed from the general reset handler, speeding up reset processing. The detection circuit is enabled by setting the CVAL bit in the Main Oscillator Control (MOSCCTL) register. The main oscillator verification error is indicated in the main oscillator fail status (MOSCFAIL) bit in the Reset Cause (RESC) register. The main oscillator verification circuit action is described in more detail in “Main Oscillator Verification Circuit” on page 203. 5.2.4 Power Control ® The Stellaris microcontroller provides an integrated LDO regulator that is used to provide power to the majority of the microcontroller's internal logic. Figure 5-4 shows the power architecture. An external LDO may not be used. Note: VDDA must be supplied with a voltage that meets the specification in Table 25-2 on page 1222, or the microcontroller does not function properly. VDDA is the supply for all of the analog circuitry on the device, including the clock circuitry. July 03, 2014 195 Texas Instruments-Production Data System Control Figure 5-4. Power Architecture VDDC Internal Logic and PLL VDDC GND GND LDO Low-Noise LDO +3.3V VDD GND I/O Buffers VDD GND VDDA GNDA Analog Circuits VDDA 5.2.5 GNDA Clock Control System control determines the control of clocks in this part. 5.2.5.1 Fundamental Clock Sources There are multiple clock sources for use in the microcontroller: ■ Precision Internal Oscillator (PIOSC). The precision internal oscillator is an on-chip clock source that is the clock source the microcontroller uses during and following POR. It does not require the use of any external components and provides a clock that is 16 MHz ±1% at room temperature and ±3% across temperature. The PIOSC allows for a reduced system cost in applications that require an accurate clock source. If the main oscillator is required, software must enable the main oscillator following reset and allow the main oscillator to stabilize before changing the clock reference. If the Hibernation Module clock source is a 32.768-kHz oscillator, the precision internal oscillator can be trimmed by software based on a reference clock for increased accuracy. ■ Main Oscillator (MOSC). The main oscillator provides a frequency-accurate clock source by one of two means: an external single-ended clock source is connected to the OSC0 input pin, or an external crystal is connected across the OSC0 input and OSC1 output pins. If the PLL is being used, the crystal value must be one of the supported frequencies between 3.579545 MHz to 196 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller 16.384 MHz (inclusive). If the PLL is not being used, the crystal may be any one of the supported frequencies between 1 MHz to 16.384 MHz. The single-ended clock source range is from DC through the specified speed of the microcontroller. The supported crystals are listed in the XTAL bit field in the RCC register (see page 219). Note that the MOSC provides the clock source for the USB PLL and must be connected to a crystal or an oscillator. ■ Internal 30-kHz Oscillator. The internal 30-kHz oscillator provides an operational frequency of 30 kHz ± 50%. It is intended for use during Deep-Sleep power-saving modes. This power-savings mode benefits from reduced internal switching and also allows the MOSC to be powered down. ■ Hibernation Module Clock Source. The Hibernation module can be clocked in one of two ways. The first way is a 4.194304-MHz crystal connected to the XOSC0 and XOSC1 pins. This clock signal is divided by 128 internally to produce the 32.768-kHz clock reference. The second way is a 32.768-kHz oscillator connected to the XOSC0 pin. The 32.768-kHz oscillator can be used for the system clock, thus eliminating the need for an additional crystal or oscillator. The Hibernation module clock source is intended to provide the system with a real-time clock source and may also provide an accurate source of Deep-Sleep or Hibernate mode power savings. The internal system clock (SysClk), is derived from any of the above sources plus two others: the output of the main internal PLL and the precision internal oscillator divided by four (4 MHz ± 1%). The frequency of the PLL clock reference must be in the range of 3.579545 MHz to 16.384 MHz (inclusive). Table 5-4 on page 197 shows how the various clock sources can be used in a system. Table 5-4. Clock Source Options 5.2.5.2 Clock Source Drive PLL? Precision Internal Oscillator Yes Used as SysClk? BYPASS = 0, OSCSRC = 0x1 Yes BYPASS = 1, OSCSRC = 0x1 Precision Internal Oscillator divide by 4 No (4 MHz ± 1%) - Yes BYPASS = 1, OSCSRC = 0x2 Main Oscillator BYPASS = 0, OSCSRC = 0x0 Yes BYPASS = 1, OSCSRC = 0x0 Yes Internal 30-kHz Oscillator No - Yes BYPASS = 1, OSCSRC = 0x3 Hibernation Module 32.768-kHz Oscillator No - Yes BYPASS = 1, OSCSRC2 = 0x7 Hibernation Module 4.194304-MHz Crystal No - No - Clock Configuration The Run-Mode Clock Configuration (RCC) and Run-Mode Clock Configuration 2 (RCC2) registers provide control for the system clock. The RCC2 register is provided to extend fields that offer additional encodings over the RCC register. When used, the RCC2 register field values are used by the logic over the corresponding field in the RCC register. In particular, RCC2 provides for a larger assortment of clock configuration options. These registers control the following clock functionality: ■ Source of clocks in sleep and deep-sleep modes ■ System clock derived from PLL or other clock source ■ Enabling/disabling of oscillators and PLL ■ Clock divisors July 03, 2014 197 Texas Instruments-Production Data System Control ■ Crystal input selection Important: Write the RCC register prior to writing the RCC2 register. If a subsequent write to the RCC register is required, include another register access after writing the RCC register and before writing the RCC2 register. Figure 5-5 shows the logic for the main clock tree. The peripheral blocks are driven by the system clock signal and can be individually enabled/disabled. When the PLL is enabled, the ADC clock signal is automatically divided down to 16 MHz from the PLL output for proper ADC operation. Note: When the ADC module is in operation, the system clock must be at least 16 MHz. When the USB module is in operation, MOSC must be the clock source, either with or without using the PLL, and the system clock must be at least 30 MHz. 198 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Figure 5-5. Main Clock Tree XTALa USBPWRDN c USB PLL (480 MHz) ÷4 USB Clock RXINT RXFRAC I2S Receive MCLK TXINT TXFRAC I2S Transmit MCLK USEPWMDIV a PWMDW a PWM Clock XTALa PWRDN b MOSCDIS a PLL (400 MHz) Main OSC USESYSDIV a,d DIV400 c ÷2 IOSCDIS a System Clock Precision Internal OSC (16 MHz) SYSDIV e ÷4 BYPASS b,d Internal OSC (30 kHz) Hibernation OSC (32.768 kHz) PWRDN ADC Clock OSCSRC b,d ÷ 25 a. Control provided by RCC register bit/field. b. Control provided by RCC register bit/field or RCC2 register bit/field, if overridden with RCC2 register bit USERCC2. c. Control provided by RCC2 register bit/field. d. Also may be controlled by DSLPCLKCFG when in deep sleep mode. e. Control provided by RCC register SYSDIV field, RCC2 register SYSDIV2 field if overridden with USERCC2 bit, or [SYSDIV2,SYSDIV2LSB] if both USERCC2 and DIV400 bits are set. Note: The figure above shows all features available on all Stellaris® Firestorm-class microcontrollers. Not all peripherals may be available on this device. Using the SYSDIV and SYSDIV2 Fields In the RCC register, the SYSDIV field specifies which divisor is used to generate the system clock from either the PLL output or the oscillator source (depending on how the BYPASS bit in this register July 03, 2014 199 Texas Instruments-Production Data System Control is configured). When using the PLL, the VCO frequency of 400 MHz is predivided by 2 before the divisor is applied. Table 5-5 shows how the SYSDIV encoding affects the system clock frequency, depending on whether the PLL is used (BYPASS=0) or another clock source is used (BYPASS=1). The divisor is equivalent to the SYSDIV encoding plus 1. For a list of possible clock sources, see Table 5-4 on page 197. Table 5-5. Possible System Clock Frequencies Using the SYSDIV Field SYSDIV 0x0 Divisor /1 a ® Frequency (BYPASS=0) Frequency (BYPASS=1) StellarisWare Parameter reserved SYSCTL_SYSDIV_1 Clock source frequency/1 0x1 /2 reserved Clock source frequency/2 SYSCTL_SYSDIV_2 0x2 /3 66.67 MHz Clock source frequency/3 SYSCTL_SYSDIV_3 0x3 /4 50 MHz Clock source frequency/4 SYSCTL_SYSDIV_4 0x4 /5 40 MHz Clock source frequency/5 SYSCTL_SYSDIV_5 0x5 /6 33.33 MHz Clock source frequency/6 SYSCTL_SYSDIV_6 0x6 /7 28.57 MHz Clock source frequency/7 SYSCTL_SYSDIV_7 0x7 /8 25 MHz Clock source frequency/8 SYSCTL_SYSDIV_8 0x8 /9 22.22 MHz Clock source frequency/9 SYSCTL_SYSDIV_9 0x9 /10 20 MHz Clock source frequency/10 SYSCTL_SYSDIV_10 0xA /11 18.18 MHz Clock source frequency/11 SYSCTL_SYSDIV_11 0xB /12 16.67 MHz Clock source frequency/12 SYSCTL_SYSDIV_12 0xC /13 15.38 MHz Clock source frequency/13 SYSCTL_SYSDIV_13 0xD /14 14.29 MHz Clock source frequency/14 SYSCTL_SYSDIV_14 0xE /15 13.33 MHz Clock source frequency/15 SYSCTL_SYSDIV_15 0xF /16 12.5 MHz (default) Clock source frequency/16 SYSCTL_SYSDIV_16 a. This parameter is used in functions such as SysCtlClockSet() in the Stellaris Peripheral Driver Library. The SYSDIV2 field in the RCC2 register is 2 bits wider than the SYSDIV field in the RCC register so that additional larger divisors up to /64 are possible, allowing a lower system clock frequency for improved Deep Sleep power consumption. When using the PLL, the VCO frequency of 400 MHz is predivided by 2 before the divisor is applied. The divisor is equivalent to the SYSDIV2 encoding plus 1. Table 5-6 shows how the SYSDIV2 encoding affects the system clock frequency, depending on whether the PLL is used (BYPASS2=0) or another clock source is used (BYPASS2=1). For a list of possible clock sources, see Table 5-4 on page 197. Table 5-6. Examples of Possible System Clock Frequencies Using the SYSDIV2 Field SYSDIV2 Divisor a Frequency (BYPASS2=0) Frequency (BYPASS2=1) StellarisWare Parameter 0x00 /1 reserved Clock source frequency/1 SYSCTL_SYSDIV_1 0x01 /2 reserved Clock source frequency/2 SYSCTL_SYSDIV_2 0x02 /3 66.67 MHz Clock source frequency/3 SYSCTL_SYSDIV_3 0x03 /4 50 MHz Clock source frequency/4 SYSCTL_SYSDIV_4 0x04 /5 40 MHz Clock source frequency/5 SYSCTL_SYSDIV_5 ... ... ... ... ... 0x09 /10 20 MHz Clock source frequency/10 SYSCTL_SYSDIV_10 ... ... ... ... ... 200 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Table 5-6. Examples of Possible System Clock Frequencies Using the SYSDIV2 Field (continued) Divisor SYSDIV2 0x3F /64 a Frequency (BYPASS2=0) Frequency (BYPASS2=1) StellarisWare Parameter 3.125 MHz Clock source frequency/64 SYSCTL_SYSDIV_64 a. This parameter is used in functions such as SysCtlClockSet() in the Stellaris Peripheral Driver Library. To allow for additional frequency choices when using the PLL, the DIV400 bit is provided along with the SYSDIV2LSB bit. When the DIV400 bit is set, bit 22 becomes the LSB for SYSDIV2. In this situation, the divisor is equivalent to the (SYSDIV2 encoding with SYSDIV2LSB appended) plus one. Table 5-7 shows the frequency choices when DIV400 is set. When the DIV400 bit is clear, SYSDIV2LSB is ignored, and the system clock frequency is determined as shown in Table 5-6 on page 200. Table 5-7. Examples of Possible System Clock Frequencies with DIV400=1 /2 reserved - /3 reserved - 1 /4 reserved - 0 /5 80 MHz SYSCTL_SYSDIV_2_5 1 /6 66.67 MHz SYSCTL_SYSDIV_3 0 /7 reserved - 1 /8 50 MHz SYSCTL_SYSDIV_4 0 /9 44.44 MHz SYSCTL_SYSDIV_4_5 1 /10 40 MHz SYSCTL_SYSDIV_5 ... ... ... ... 0 /127 3.15 MHz SYSCTL_SYSDIV_63_5 1 /128 3.125 MHz SYSCTL_SYSDIV_64 0x00 reserved 0 0x01 0x02 0x03 0x04 ... 0x3F b StellarisWare Parameter SYSDIV2LSB Divisor a Frequency (BYPASS2=0) SYSDIV2 a. Note that DIV400 and SYSDIV2LSB are only valid when BYPASS2=0. b. This parameter is used in functions such as SysCtlClockSet() in the Stellaris Peripheral Driver Library. 5.2.5.3 Precision Internal Oscillator Operation (PIOSC) The microcontroller powers up with the PIOSC running. If another clock source is desired, the PIOSC must remain enabled as it is used for internal functions. The PIOSC can only be disabled during Deep-Sleep mode. It can be powered down by setting the IOSCDIS bit in the RCC register. The PIOSC generates a 16-MHz clock with a ±1% accuracy at room temperatures. Across the extended temperature range, the accuracy is ±3%. At the factory, the PIOSC is set to 16 MHz at room temperature, however, the frequency can be trimmed for other voltage or temperature conditions using software in one of three ways: ■ Default calibration: clear the UTEN bit and set the UPDATE bit in the Precision Internal Oscillator Calibration (PIOSCCAL) register. ■ User-defined calibration: The user can program the UT value to adjust the PIOSC frequency. As the UT value increases, the generated period increases. To commit a new UT value, first set the UTEN bit, then program the UT field, and then set the UPDATE bit. The adjustment finishes within a few clock periods and is glitch free. July 03, 2014 201 Texas Instruments-Production Data System Control ■ Automatic calibration using the Hibernation module with a functioning 32.768-kHz clock source: Set the CAL bit in the PIOSCCAL register; the results of the calibration are shown in the RESULT field in the Precision Internal Oscillator Statistic (PIOSCSTAT) register. After calibration is complete, the PIOSC is trimmed using the trimmed value returned in the CT field. 5.2.5.4 Crystal Configuration for the Main Oscillator (MOSC) The main oscillator supports the use of a select number of crystals. If the main oscillator is used by the PLL as a reference clock, the supported range of crystals is 3.579545 to 16.384 MHz, otherwise, the range of supported crystals is 1 to 16.384 MHz. The XTAL bit in the RCC register (see page 219) describes the available crystal choices and default programming values. Software configures the RCC register XTAL field with the crystal number. If the PLL is used in the design, the XTAL field value is internally translated to the PLL settings. 5.2.5.5 Main PLL Frequency Configuration The main PLL is disabled by default during power-on reset and is enabled later by software if required. Software specifies the output divisor to set the system clock frequency and enables the main PLL to drive the output. The PLL operates at 400 MHz, but is divided by two prior to the application of the output divisor, unless the DIV400 bit in the RCC2 register is set. To configure the PIOSC to be the clock source for the main PLL, program the OSCRC2 field in the Run-Mode Clock Configuration 2 (RCC2) register to be 0x1. If the main oscillator provides the clock reference to the main PLL, the translation provided by hardware and used to program the PLL is available for software in the XTAL to PLL Translation (PLLCFG) register (see page 223). The internal translation provides a translation within ± 1% of the targeted PLL VCO frequency. Table 25-8 on page 1228 shows the actual PLL frequency and error for a given crystal choice. The Crystal Value field (XTAL) in the Run-Mode Clock Configuration (RCC) register (see page 219) describes the available crystal choices and default programming of the PLLCFG register. Any time the XTAL field changes, the new settings are translated and the internal PLL settings are updated. 5.2.5.6 USB PLL Frequency Configuration The USB PLL is disabled by default during power-on reset and is enabled later by software. The USB PLL must be enabled and running for proper USB function. The main oscillator is the only clock reference for the USB PLL. The USB PLL is enabled by clearing the USBPWRDN bit of the RCC2 register. The XTAL bit field (Crystal Value) of the RCC register describes the available crystal choices. The main oscillator must be connected to one of the following crystal values in order to correctly generate the USB clock: 4, 5, 6, 8, 10, 12, or 16 MHz. Only these crystals provide the necessary USB PLL VCO frequency to conform with the USB timing specifications. 5.2.5.7 PLL Modes Both PLLs have two modes of operation: Normal and Power-Down ■ Normal: The PLL multiplies the input clock reference and drives the output. ■ Power-Down: Most of the PLL internal circuitry is disabled and the PLL does not drive the output. The modes are programmed using the RCC/RCC2 register fields (see page 219 and page 226). 202 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller 5.2.5.8 PLL Operation If a PLL configuration is changed, the PLL output frequency is unstable until it reconverges (relocks) to the new setting. The time between the configuration change and relock is TREADY (see Table 25-7 on page 1227). During the relock time, the affected PLL is not usable as a clock reference. Either PLL is changed by one of the following: ■ Change to the XTAL value in the RCC register—writes of the same value do not cause a relock. ■ Change in the PLL from Power-Down to Normal mode. A counter clocked by the system clock is used to measure the TREADY requirement. If the system clock is the main oscillator and it is running off an 8.192 MHz or slower external oscillator clock, the down counter is set to 0x1200 (that is, ~600 μs at an 8.192 MHz). If the system clock is running off the PIOSC or an external oscillator clock that is faster than 8.192 MHz, the down counter is set to 0x2400. Hardware is provided to keep the PLL from being used as a system clock until the TREADY condition is met after one of the two changes above. It is the user's responsibility to have a stable clock source (like the main oscillator) before the RCC/RCC2 register is switched to use the PLL. If the main PLL is enabled and the system clock is switched to use the PLL in one step, the system control hardware continues to clock the microcontroller from the oscillator selected by the RCC/RCC2 register until the main PLL is stable (TREADY time met), after which it changes to the PLL. Software can use many methods to ensure that the system is clocked from the main PLL, including periodically polling the PLLLRIS bit in the Raw Interrupt Status (RIS) register, and enabling the PLL Lock interrupt. The USB PLL is not protected during the lock time (TREADY), and software should ensure that the USB PLL has locked before using the interface. Software can use many methods to ensure the TREADY period has passed, including periodically polling the USBPLLLRIS bit in the Raw Interrupt Status (RIS) register, and enabling the USB PLL Lock interrupt. 5.2.5.9 Main Oscillator Verification Circuit The clock control includes circuitry to ensure that the main oscillator is running at the appropriate frequency. The circuit monitors the main oscillator frequency and signals if the frequency is outside of the allowable band of attached crystals. The detection circuit is enabled using the CVAL bit in the Main Oscillator Control (MOSCCTL) register. If this circuit is enabled and detects an error, the following sequence is performed by the hardware: 1. The MOSCFAIL bit in the Reset Cause (RESC) register is set. 2. If the internal oscillator (PIOSC) is disabled, it is enabled. 3. The system clock is switched from the main oscillator to the PIOSC. 4. An internal power-on reset is initiated that lasts for 32 PIOSC periods. 5. Reset is de-asserted and the processor is directed to the NMI handler during the reset sequence. 5.2.6 System Control For power-savings purposes, the RCGCn, SCGCn, and DCGCn registers control the clock gating logic for each peripheral or block in the system while the microcontroller is in Run, Sleep, and Deep-Sleep mode, respectively. These registers are located in the System Control register map July 03, 2014 203 Texas Instruments-Production Data System Control starting at offsets 0x600, 0x700, and 0x800, respectively. There must be a delay of 3 system clocks after a peripheral module clock is enabled in the RCGC register before any module registers are accessed. There are four levels of operation for the microcontroller defined as: ■ Run mode ■ Sleep mode ■ Deep-Sleep mode ■ Hibernate mode The following sections describe the different modes in detail. Caution – If the Cortex-M3 Debug Access Port (DAP) has been enabled, and the device wakes from a low power sleep or deep-sleep mode, the core may start executing code before all clocks to peripherals have been restored to their Run mode configuration. The DAP is usually enabled by software tools accessing the JTAG or SWD interface when debugging or flash programming. If this condition occurs, a Hard Fault is triggered when software accesses a peripheral with an invalid clock. A software delay loop can be used at the beginning of the interrupt routine that is used to wake up a system from a WFI (Wait For Interrupt) instruction. This stalls the execution of any code that accesses a peripheral register that might cause a fault. This loop can be removed for production software as the DAP is most likely not enabled during normal execution. Because the DAP is disabled by default (power on reset), the user can also power cycle the device. The DAP is not enabled unless it is enabled through the JTAG or SWD interface. 5.2.6.1 Run Mode In Run mode, the microcontroller actively executes code. Run mode provides normal operation of the processor and all of the peripherals that are currently enabled by the RCGCn registers. The system clock can be any of the available clock sources including the PLL. 5.2.6.2 Sleep Mode In Sleep mode, the clock frequency of the active peripherals is unchanged, but the processor and the memory subsystem are not clocked and therefore no longer execute code. Sleep mode is entered by the Cortex-M3 core executing a WFI (Wait for Interrupt) instruction. Any properly configured interrupt event in the system brings the processor back into Run mode. See “Power Management” on page 106 for more details. Peripherals are clocked that are enabled in the SCGCn registers when auto-clock gating is enabled (see the RCC register) or the RCGCn registers when the auto-clock gating is disabled. The system clock has the same source and frequency as that during Run mode. 5.2.6.3 Deep-Sleep Mode In Deep-Sleep mode, the clock frequency of the active peripherals may change (depending on the Run mode clock configuration) in addition to the processor clock being stopped. An interrupt returns the microcontroller to Run mode from one of the sleep modes; the sleep modes are entered on request from the code. Deep-Sleep mode is entered by first setting the SLEEPDEEP bit in the System Control (SYSCTRL) register (see page 148) and then executing a WFI instruction. Any properly configured interrupt event in the system brings the processor back into Run mode. See “Power Management” on page 106 for more details. 204 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller The Cortex-M3 processor core and the memory subsystem are not clocked in Deep-Sleep mode. Peripherals are clocked that are enabled in the DCGCn registers when auto-clock gating is enabled (see the RCC register) or the RCGCn registers when auto-clock gating is disabled. The system clock source is specified in the DSLPCLKCFG register. When the DSLPCLKCFG register is used, the internal oscillator source is powered up, if necessary, and other clocks are powered down. If the PLL is running at the time of the WFI instruction, hardware powers the PLL down and overrides the SYSDIV field of the active RCC/RCC2 register, to be determined by the DSDIVORIDE setting in the DSLPCLKCFG register, up to /16 or /64 respectively. When the Deep-Sleep exit event occurs, hardware brings the system clock back to the source and frequency it had at the onset of Deep-Sleep mode before enabling the clocks that had been stopped during the Deep-Sleep duration. If the PIOSC is used as the PLL reference clock source, it may continue to provide the clock during Deep-Sleep. See page 230. 5.2.6.4 Hibernate Mode In this mode, the power supplies are turned off to the main part of the microcontroller and only the Hibernation module's circuitry is active. An external wake event or RTC event is required to bring the microcontroller back to Run mode. The Cortex-M3 processor and peripherals outside of the Hibernation module see a normal "power on" sequence and the processor starts running code. Software can determine if the microcontroller has been restarted from Hibernate mode by inspecting the Hibernation module registers. For more information on the operation of Hibernate mode, see “Hibernation Module” on page 293. 5.3 Initialization and Configuration The PLL is configured using direct register writes to the RCC/RCC2 register. If the RCC2 register is being used, the USERCC2 bit must be set and the appropriate RCC2 bit/field is used. The steps required to successfully change the PLL-based system clock are: 1. Bypass the PLL and system clock divider by setting the BYPASS bit and clearing the USESYS bit in the RCC register, thereby configuring the microcontroller to run off a "raw" clock source and allowing for the new PLL configuration to be validated before switching the system clock to the PLL. 2. Select the crystal value (XTAL) and oscillator source (OSCSRC), and clear the PWRDN bit in RCC/RCC2. Setting the XTAL field automatically pulls valid PLL configuration data for the appropriate crystal, and clearing the PWRDN bit powers and enables the PLL and its output. 3. Select the desired system divider (SYSDIV) in RCC/RCC2 and set the USESYS bit in RCC. The SYSDIV field determines the system frequency for the microcontroller. 4. Wait for the PLL to lock by polling the PLLLRIS bit in the Raw Interrupt Status (RIS) register. 5. Enable use of the PLL by clearing the BYPASS bit in RCC/RCC2. 5.4 Register Map Table 5-8 on page 206 lists the System Control registers, grouped by function. The offset listed is a hexadecimal increment to the register's address, relative to the System Control base address of 0x400F.E000. Note: Spaces in the System Control register space that are not used are reserved for future or internal use. Software should not modify any reserved memory address. July 03, 2014 205 Texas Instruments-Production Data System Control Additional Flash and ROM registers defined in the System Control register space are described in the “Internal Memory” on page 320. Table 5-8. System Control Register Map Description See page Offset Name Type Reset 0x000 DID0 RO - Device Identification 0 208 0x004 DID1 RO - Device Identification 1 237 0x008 DC0 RO 0x017F.00BF Device Capabilities 0 239 0x010 DC1 RO - Device Capabilities 1 240 0x014 DC2 RO 0x570F.5037 Device Capabilities 2 242 0x018 DC3 RO 0xBFFF.7FC0 Device Capabilities 3 244 0x01C DC4 RO 0x5004.F1FF Device Capabilities 4 246 0x020 DC5 RO 0x0000.0000 Device Capabilities 5 248 0x024 DC6 RO 0x0000.0013 Device Capabilities 6 249 0x028 DC7 RO 0xFFFF.FFFF Device Capabilities 7 250 0x02C DC8 RO 0xFFFF.FFFF Device Capabilities 8 ADC Channels 254 0x030 PBORCTL R/W 0x0000.0002 Brown-Out Reset Control 210 0x040 SRCR0 R/W 0x00000000 Software Reset Control 0 286 0x044 SRCR1 R/W 0x00000000 Software Reset Control 1 288 0x048 SRCR2 R/W 0x00000000 Software Reset Control 2 291 0x050 RIS RO 0x0000.0000 Raw Interrupt Status 211 0x054 IMC R/W 0x0000.0000 Interrupt Mask Control 213 0x058 MISC R/W1C 0x0000.0000 Masked Interrupt Status and Clear 215 0x05C RESC R/W - Reset Cause 217 0x060 RCC R/W 0x0780.3AD1 Run-Mode Clock Configuration 219 0x064 PLLCFG RO - XTAL to PLL Translation 223 0x06C GPIOHBCTL R/W 0x0000.0000 GPIO High-Performance Bus Control 224 0x070 RCC2 R/W 0x07C0.6810 Run-Mode Clock Configuration 2 226 0x07C MOSCCTL R/W 0x0000.0000 Main Oscillator Control 229 0x100 RCGC0 R/W 0x00000040 Run Mode Clock Gating Control Register 0 260 0x104 RCGC1 R/W 0x00000000 Run Mode Clock Gating Control Register 1 268 0x108 RCGC2 R/W 0x00000000 Run Mode Clock Gating Control Register 2 277 0x110 SCGC0 R/W 0x00000040 Sleep Mode Clock Gating Control Register 0 263 0x114 SCGC1 R/W 0x00000000 Sleep Mode Clock Gating Control Register 1 271 0x118 SCGC2 R/W 0x00000000 Sleep Mode Clock Gating Control Register 2 280 206 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Table 5-8. System Control Register Map (continued) Name Type Reset 0x120 DCGC0 R/W 0x00000040 Deep Sleep Mode Clock Gating Control Register 0 266 0x124 DCGC1 R/W 0x00000000 Deep-Sleep Mode Clock Gating Control Register 1 274 0x128 DCGC2 R/W 0x00000000 Deep Sleep Mode Clock Gating Control Register 2 283 0x144 DSLPCLKCFG R/W 0x0780.0000 Deep Sleep Clock Configuration 230 0x150 PIOSCCAL R/W 0x0000.0000 Precision Internal Oscillator Calibration 232 0x154 PIOSCSTAT RO 0x0000.0040 Precision Internal Oscillator Statistics 234 0x170 I2SMCLKCFG R/W 0x0000.0000 I2S MCLK Configuration 235 0x190 DC9 RO 0x00FF.00FF Device Capabilities 9 ADC Digital Comparators 257 0x1A0 NVMSTAT RO 0x0000.0001 Non-Volatile Memory Information 259 5.5 Description See page Offset Register Descriptions All addresses given are relative to the System Control base address of 0x400F.E000. July 03, 2014 207 Texas Instruments-Production Data System Control Register 1: Device Identification 0 (DID0), offset 0x000 This register identifies the version of the microcontroller. Each microcontroller is uniquely identified by the combined values of the CLASS field in the DID0 register and the PARTNO field in the DID1 register. Device Identification 0 (DID0) Base 0x400F.E000 Offset 0x000 Type RO, reset 31 30 reserved Type Reset 29 28 27 26 VER 25 24 23 22 21 20 reserved 18 17 16 CLASS RO 0 RO 0 RO 0 RO 1 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 1 RO 1 RO 0 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 RO - RO - RO - RO - RO - RO - RO - RO - RO - RO - RO - RO - RO - RO - RO - RO - MAJOR Type Reset 19 MINOR Bit/Field Name Type Reset 31 reserved RO 0 30:28 VER RO 0x1 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. DID0 Version This field defines the DID0 register format version. The version number is numeric. The value of the VER field is encoded as follows (all other encodings are reserved): Value Description 0x1 Second version of the DID0 register format. 27:24 reserved RO 0x0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 23:16 CLASS RO 0x06 Device Class The CLASS field value identifies the internal design from which all mask sets are generated for all microcontrollers in a particular product line. The CLASS field value is changed for new product lines, for changes in fab process (for example, a remap or shrink), or any case where the MAJOR or MINOR fields require differentiation from prior microcontrollers. The value of the CLASS field is encoded as follows (all other encodings are reserved): Value Description 0x06 Stellaris® Firestorm-class microcontrollers 208 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Bit/Field Name Type Reset 15:8 MAJOR RO - Description Major Revision This field specifies the major revision number of the microcontroller. The major revision reflects changes to base layers of the design. The major revision number is indicated in the part number as a letter (A for first revision, B for second, and so on). This field is encoded as follows: Value Description 0x0 Revision A (initial device) 0x1 Revision B (first base layer revision) 0x2 Revision C (second base layer revision) and so on. 7:0 MINOR RO - Minor Revision This field specifies the minor revision number of the microcontroller. The minor revision reflects changes to the metal layers of the design. The MINOR field value is reset when the MAJOR field is changed. This field is numeric and is encoded as follows: Value Description 0x0 Initial device, or a major revision update. 0x1 First metal layer change. 0x2 Second metal layer change. and so on. July 03, 2014 209 Texas Instruments-Production Data System Control Register 2: Brown-Out Reset Control (PBORCTL), offset 0x030 This register is responsible for controlling reset conditions after initial power-on reset. Brown-Out Reset Control (PBORCTL) Base 0x400F.E000 Offset 0x030 Type R/W, reset 0x0000.0002 31 30 29 28 27 26 25 24 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 8 7 6 5 4 3 2 1 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 reserved Type Reset reserved Type Reset BORIOR reserved R/W 1 RO 0 Bit/Field Name Type Reset Description 31:2 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 1 BORIOR R/W 1 BOR Interrupt or Reset Value Description 0 reserved RO 0 0 A Brown Out Event causes an interrupt to be generated to the interrupt controller. 1 A Brown Out Event causes a reset of the microcontroller. Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 210 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 3: Raw Interrupt Status (RIS), offset 0x050 This register indicates the status for system control raw interrupts. An interrupt is sent to the interrupt controller if the corresponding bit in the Interrupt Mask Control (IMC) register is set. Writing a 1 to the corresponding bit in the Masked Interrupt Status and Clear (MISC) register clears an interrupt status bit. Raw Interrupt Status (RIS) Base 0x400F.E000 Offset 0x050 Type RO, reset 0x0000.0000 31 30 29 28 27 26 25 24 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 8 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 7 6 5 4 3 2 1 0 BORRIS reserved RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 reserved Type Reset reserved Type Reset RO 0 MOSCPUPRIS USBPLLLRIS Bit/Field Name Type Reset 31:9 reserved RO 0x0000.00 8 MOSCPUPRIS RO 0 RO 0 RO 0 PLLLRIS RO 0 reserved Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. MOSC Power Up Raw Interrupt Status Value Description 1 Sufficient time has passed for the MOSC to reach the expected frequency. The value for this power-up time is indicated by TMOSC_START. 0 Sufficient time has not passed for the MOSC to reach the expected frequency. This bit is cleared by writing a 1 to the MOSCPUPMIS bit in the MISC register. 7 USBPLLLRIS RO 0 USB PLL Lock Raw Interrupt Status Value Description 1 The USB PLL timer has reached TREADY indicating that sufficient time has passed for the USB PLL to lock. 0 The USB PLL timer has not reached TREADY. This bit is cleared by writing a 1 to the USBPLLLMIS bit in the MISC register. 6 PLLLRIS RO 0 PLL Lock Raw Interrupt Status Value Description 1 The PLL timer has reached TREADY indicating that sufficient time has passed for the PLL to lock. 0 The PLL timer has not reached TREADY. This bit is cleared by writing a 1 to the PLLLMIS bit in the MISC register. July 03, 2014 211 Texas Instruments-Production Data System Control Bit/Field Name Type Reset 5:2 reserved RO 0x0 1 BORRIS RO 0 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. Brown-Out Reset Raw Interrupt Status Value Description 1 A brown-out condition is currently active. 0 A brown-out condition is not currently active. Note the BORIOR bit in the PBORCTL register must be cleared to cause an interrupt due to a Brown Out Event. This bit is cleared by writing a 1 to the BORMIS bit in the MISC register. 0 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 212 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 4: Interrupt Mask Control (IMC), offset 0x054 This register contains the mask bits for system control raw interrupts. A raw interrupt, indicated by a bit being set in the Raw Interrupt Status (RIS) register, is sent to the interrupt controller if the corresponding bit in this register is set. Interrupt Mask Control (IMC) Base 0x400F.E000 Offset 0x054 Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 8 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 7 6 5 4 3 2 1 0 BORIM reserved RO 0 RO 0 RO 0 RO 0 R/W 0 RO 0 reserved Type Reset reserved Type Reset RO 0 MOSCPUPIM USBPLLLIM Bit/Field Name Type Reset 31:9 reserved RO 0x0000.00 8 MOSCPUPIM R/W 0 R/W 0 R/W 0 PLLLIM R/W 0 reserved Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. MOSC Power Up Interrupt Mask Value Description 7 USBPLLLIM R/W 0 1 An interrupt is sent to the interrupt controller when the MOSCPUPRIS bit in the RIS register is set. 0 The MOSCPUPRIS interrupt is suppressed and not sent to the interrupt controller. USB PLL Lock Interrupt Mask Value Description 6 PLLLIM R/W 0 1 An interrupt is sent to the interrupt controller when the USBPLLLRIS bit in the RIS register is set. 0 The USBPLLLRIS interrupt is suppressed and not sent to the interrupt controller. PLL Lock Interrupt Mask Value Description 5:2 reserved RO 0x0 1 An interrupt is sent to the interrupt controller when the PLLLRIS bit in the RIS register is set. 0 The PLLLRIS interrupt is suppressed and not sent to the interrupt controller. Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. July 03, 2014 213 Texas Instruments-Production Data System Control Bit/Field Name Type Reset 1 BORIM R/W 0 Description Brown-Out Reset Interrupt Mask Value Description 0 reserved RO 0 1 An interrupt is sent to the interrupt controller when the BORRIS bit in the RIS register is set. 0 The BORRIS interrupt is suppressed and not sent to the interrupt controller. Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 214 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 5: Masked Interrupt Status and Clear (MISC), offset 0x058 On a read, this register gives the current masked status value of the corresponding interrupt in the Raw Interrupt Status (RIS) register. All of the bits are R/W1C, thus writing a 1 to a bit clears the corresponding raw interrupt bit in the RIS register (see page 211). Masked Interrupt Status and Clear (MISC) Base 0x400F.E000 Offset 0x058 Type R/W1C, reset 0x0000.0000 31 30 29 28 27 26 25 24 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 8 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 7 6 5 4 3 2 1 0 RO 0 RO 0 RO 0 RO 0 reserved Type Reset reserved Type Reset RO 0 MOSCPUPMIS USBPLLLMIS Bit/Field Name Type Reset 31:9 reserved RO 0x0000.00 8 MOSCPUPMIS R/W1C 0 R/W1C 0 R/W1C 0 PLLLMIS R/W1C 0 reserved BORMIS reserved R/W1C 0 RO 0 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. MOSC Power Up Masked Interrupt Status Value Description 1 When read, a 1 indicates that an unmasked interrupt was signaled because sufficient time has passed for the MOSC PLL to lock. Writing a 1 to this bit clears it and also the MOSCPUPRIS bit in the RIS register. 0 When read, a 0 indicates that sufficient time has not passed for the MOSC PLL to lock. A write of 0 has no effect on the state of this bit. 7 USBPLLLMIS R/W1C 0 USB PLL Lock Masked Interrupt Status Value Description 1 When read, a 1 indicates that an unmasked interrupt was signaled because sufficient time has passed for the USB PLL to lock. Writing a 1 to this bit clears it and also the USBPLLLRIS bit in the RIS register. 0 When read, a 0 indicates that sufficient time has not passed for the USB PLL to lock. A write of 0 has no effect on the state of this bit. July 03, 2014 215 Texas Instruments-Production Data System Control Bit/Field Name Type Reset 6 PLLLMIS R/W1C 0 Description PLL Lock Masked Interrupt Status Value Description 1 When read, a 1 indicates that an unmasked interrupt was signaled because sufficient time has passed for the PLL to lock. Writing a 1 to this bit clears it and also the PLLLRIS bit in the RIS register. 0 When read, a 0 indicates that sufficient time has not passed for the PLL to lock. A write of 0 has no effect on the state of this bit. 5:2 reserved RO 0x0 1 BORMIS R/W1C 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. BOR Masked Interrupt Status Value Description 1 When read, a 1 indicates that an unmasked interrupt was signaled because of a brown-out condition. Writing a 1 to this bit clears it and also the BORRIS bit in the RIS register. 0 When read, a 0 indicates that a brown-out condition has not occurred. A write of 0 has no effect on the state of this bit. 0 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 216 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 6: Reset Cause (RESC), offset 0x05C This register is set with the reset cause after reset. The bits in this register are sticky and maintain their state across multiple reset sequences, except when a power- on reset or an external reset is the cause, in which case, all bits other than POR or EXT in the RESC register are cleared. Reset Cause (RESC) Base 0x400F.E000 Offset 0x05C Type R/W, reset 31 30 29 28 27 26 25 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 RO 0 RO 0 RO 0 RO 0 RO 0 24 23 22 21 20 19 18 17 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 R/W - 9 8 7 6 5 4 3 2 1 0 WDT1 SW WDT0 BOR POR EXT RO 0 RO 0 RO 0 RO 0 R/W - R/W - R/W - R/W - R/W - R/W - reserved Type Reset MOSCFAIL reserved Type Reset RO 0 16 Bit/Field Name Type Reset Description 31:17 reserved RO 0x000 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 16 MOSCFAIL R/W - MOSC Failure Reset Value Description 1 When read, this bit indicates that the MOSC circuit was enabled for clock validation and failed, generating a reset event. 0 When read, this bit indicates that a MOSC failure has not generated a reset since the previous power-on reset. Writing a 0 to this bit clears it. 15:6 reserved RO 0x00 5 WDT1 R/W - Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. Watchdog Timer 1 Reset Value Description 1 When read, this bit indicates that Watchdog Timer 1 timed out and generated a reset. 0 When read, this bit indicates that Watchdog Timer 1 has not generated a reset since the previous power-on reset. Writing a 0 to this bit clears it. July 03, 2014 217 Texas Instruments-Production Data System Control Bit/Field Name Type Reset 4 SW R/W - Description Software Reset Value Description 1 When read, this bit indicates that a software reset has caused a reset event. 0 When read, this bit indicates that a software reset has not generated a reset since the previous power-on reset. Writing a 0 to this bit clears it. 3 WDT0 R/W - Watchdog Timer 0 Reset Value Description 1 When read, this bit indicates that Watchdog Timer 0 timed out and generated a reset. 0 When read, this bit indicates that Watchdog Timer 0 has not generated a reset since the previous power-on reset. Writing a 0 to this bit clears it. 2 BOR R/W - Brown-Out Reset Value Description 1 When read, this bit indicates that a brown-out reset has caused a reset event. 0 When read, this bit indicates that a brown-out reset has not generated a reset since the previous power-on reset. Writing a 0 to this bit clears it. 1 POR R/W - Power-On Reset Value Description 1 When read, this bit indicates that a power-on reset has caused a reset event. 0 When read, this bit indicates that a power-on reset has not generated a reset. Writing a 0 to this bit clears it. 0 EXT R/W - External Reset Value Description 1 When read, this bit indicates that an external reset (RST assertion) has caused a reset event. 0 When read, this bit indicates that an external reset (RST assertion) has not caused a reset event since the previous power-on reset. Writing a 0 to this bit clears it. 218 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 7: Run-Mode Clock Configuration (RCC), offset 0x060 The bits in this register configure the system clock and oscillators. Important: Write the RCC register prior to writing the RCC2 register. If a subsequent write to the RCC register is required, include another register access after writing the RCC register and before writing the RCC2 register. Run-Mode Clock Configuration (RCC) Base 0x400F.E000 Offset 0x060 Type R/W, reset 0x0780.3AD1 31 30 29 28 RO 0 RO 0 RO 0 RO 0 15 14 13 12 reserved Type Reset reserved Type Reset RO 0 RO 0 27 26 25 24 23 R/W 0 R/W 1 R/W 1 R/W 1 R/W 1 11 10 9 8 R/W 0 R/W 1 ACG PWRDN reserved BYPASS R/W 1 RO 1 21 20 19 R/W 0 RO 0 RO 0 RO 0 7 6 5 4 3 R/W 1 R/W 1 R/W 0 R/W 1 RO 0 SYSDIV 22 Bit/Field Name Type Reset 31:28 reserved RO 0x0 27 ACG R/W 0 R/W 0 17 16 RO 0 RO 0 RO 0 2 1 0 reserved USESYSDIV XTAL R/W 1 18 OSCSRC reserved RO 0 IOSCDIS MOSCDIS R/W 0 R/W 1 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. Auto Clock Gating This bit specifies whether the system uses the Sleep-Mode Clock Gating Control (SCGCn) registers and Deep-Sleep-Mode Clock Gating Control (DCGCn) registers if the microcontroller enters a Sleep or Deep-Sleep mode (respectively). Value Description 1 The SCGCn or DCGCn registers are used to control the clocks distributed to the peripherals when the microcontroller is in a sleep mode. The SCGCn and DCGCn registers allow unused peripherals to consume less power when the microcontroller is in a sleep mode. 0 The Run-Mode Clock Gating Control (RCGCn) registers are used when the microcontroller enters a sleep mode. The RCGCn registers are always used to control the clocks in Run mode. 26:23 SYSDIV R/W 0xF System Clock Divisor Specifies which divisor is used to generate the system clock from either the PLL output or the oscillator source (depending on how the BYPASS bit in this register is configured). See Table 5-5 on page 200 for bit encodings. If the SYSDIV value is less than MINSYSDIV (see page 240), and the PLL is being used, then the MINSYSDIV value is used as the divisor. If the PLL is not being used, the SYSDIV value can be less than MINSYSDIV. July 03, 2014 219 Texas Instruments-Production Data System Control Bit/Field Name Type Reset 22 USESYSDIV R/W 0 Description Enable System Clock Divider Value Description 1 The system clock divider is the source for the system clock. The system clock divider is forced to be used when the PLL is selected as the source. If the USERCC2 bit in the RCC2 register is set, then the SYSDIV2 field in the RCC2 register is used as the system clock divider rather than the SYSDIV field in this register. 0 The system clock is used undivided. 21:14 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 13 PWRDN R/W 1 PLL Power Down Value Description 1 The PLL is powered down. Care must be taken to ensure that another clock source is functioning and that the BYPASS bit is set before setting this bit. 0 The PLL is operating normally. 12 reserved RO 1 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 11 BYPASS R/W 1 PLL Bypass Value Description 1 The system clock is derived from the OSC source and divided by the divisor specified by SYSDIV. 0 The system clock is the PLL output clock divided by the divisor specified by SYSDIV. See Table 5-5 on page 200 for programming guidelines. Note: The ADC must be clocked from the PLL or directly from a 16-MHz clock source to operate properly. 220 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Bit/Field Name Type Reset Description 10:6 XTAL R/W 0x0B Crystal Value This field specifies the crystal value attached to the main oscillator. The encoding for this field is provided below. Depending on the crystal used, the PLL frequency may not be exactly 400 MHz, see Table 25-8 on page 1228 for more information. Frequencies that may be used with the USB interface are indicated in the table. To function within the clocking requirements of the USB specification, a crystal of 4, 5, 6, 8, 10, 12, or 16 MHz must be used. Value Crystal Frequency (MHz) Not Crystal Frequency (MHz) Using Using the PLL the PLL 0x00 1.000 MHz reserved 0x01 1.8432 MHz reserved 0x02 2.000 MHz reserved 0x03 2.4576 MHz 0x04 reserved 3.579545 MHz 0x05 3.6864 MHz 0x06 4 MHz (USB) 0x07 4.096 MHz 0x08 4.9152 MHz 0x09 5 MHz (USB) 0x0A 5.12 MHz 0x0B 6 MHz (reset value)(USB) 0x0C 6.144 MHz 0x0D 7.3728 MHz 0x0E 8 MHz (USB) 0x0F 8.192 MHz 0x10 10.0 MHz (USB) 0x11 12.0 MHz (USB) 0x12 12.288 MHz 0x13 13.56 MHz 0x14 14.31818 MHz 0x15 16.0 MHz (USB) 0x16 16.384 MHz July 03, 2014 221 Texas Instruments-Production Data System Control Bit/Field Name Type Reset 5:4 OSCSRC R/W 0x1 Description Oscillator Source Selects the input source for the OSC. The values are: Value Input Source 0x0 MOSC Main oscillator 0x1 PIOSC Precision internal oscillator (default) 0x2 PIOSC/4 Precision internal oscillator / 4 0x3 30 kHz 30-kHz internal oscillator For additional oscillator sources, see the RCC2 register. 3:2 reserved RO 0x0 1 IOSCDIS R/W 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. Precision Internal Oscillator Disable Value Description 0 MOSCDIS R/W 1 1 The precision internal oscillator (PIOSC) is disabled. 0 The precision internal oscillator is enabled. Main Oscillator Disable Value Description 1 The main oscillator is disabled (default). 0 The main oscillator is enabled. 222 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 8: XTAL to PLL Translation (PLLCFG), offset 0x064 This register provides a means of translating external crystal frequencies into the appropriate PLL settings. This register is initialized during the reset sequence and updated anytime that the XTAL field changes in the Run-Mode Clock Configuration (RCC) register (see page 219). The PLL frequency is calculated using the PLLCFG field values, as follows: PLLFreq = OSCFreq * F / (R + 1) XTAL to PLL Translation (PLLCFG) Base 0x400F.E000 Offset 0x064 Type RO, reset 31 30 29 28 27 26 25 24 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 RO - RO - RO - RO - RO - 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 8 7 6 5 4 3 2 1 0 RO - RO - RO - RO - RO - RO - RO - RO - RO - reserved Type Reset reserved Type Reset RO 0 RO 0 F Bit/Field Name Type Reset 31:14 reserved RO 0x0000.0 13:5 F RO - R Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. PLL F Value This field specifies the value supplied to the PLL’s F input. 4:0 R RO - PLL R Value This field specifies the value supplied to the PLL’s R input. July 03, 2014 223 Texas Instruments-Production Data System Control Register 9: GPIO High-Performance Bus Control (GPIOHBCTL), offset 0x06C This register controls which internal bus is used to access each GPIO port. When a bit is clear, the corresponding GPIO port is accessed across the legacy Advanced Peripheral Bus (APB) bus and through the APB memory aperture. When a bit is set, the corresponding port is accessed across the Advanced High-Performance Bus (AHB) bus and through the AHB memory aperture. Each GPIO port can be individually configured to use AHB or APB, but may be accessed only through one aperture. The AHB bus provides better back-to-back access performance than the APB bus. The address aperture in the memory map changes for the ports that are enabled for AHB access (see Table 9-7 on page 438). GPIO High-Performance Bus Control (GPIOHBCTL) Base 0x400F.E000 Offset 0x06C Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 8 7 6 5 4 3 2 1 0 PORTJ PORTH PORTG PORTF PORTE PORTD PORTC PORTB PORTA R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 reserved Type Reset reserved Type Reset RO 0 Bit/Field Name Type Reset 31:9 reserved RO 0x0000.0 8 PORTJ R/W 0 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. Port J Advanced High-Performance Bus This bit defines the memory aperture for Port J. Value Description 7 PORTH R/W 0 1 Advanced High-Performance Bus (AHB) 0 Advanced Peripheral Bus (APB). This bus is the legacy bus. Port H Advanced High-Performance Bus This bit defines the memory aperture for Port H. Value Description 6 PORTG R/W 0 1 Advanced High-Performance Bus (AHB) 0 Advanced Peripheral Bus (APB). This bus is the legacy bus. Port G Advanced High-Performance Bus This bit defines the memory aperture for Port G. Value Description 1 Advanced High-Performance Bus (AHB) 0 Advanced Peripheral Bus (APB). This bus is the legacy bus. 224 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Bit/Field Name Type Reset 5 PORTF R/W 0 Description Port F Advanced High-Performance Bus This bit defines the memory aperture for Port F. Value Description 4 PORTE R/W 0 1 Advanced High-Performance Bus (AHB) 0 Advanced Peripheral Bus (APB). This bus is the legacy bus. Port E Advanced High-Performance Bus This bit defines the memory aperture for Port E. Value Description 3 PORTD R/W 0 1 Advanced High-Performance Bus (AHB) 0 Advanced Peripheral Bus (APB). This bus is the legacy bus. Port D Advanced High-Performance Bus This bit defines the memory aperture for Port D. Value Description 2 PORTC R/W 0 1 Advanced High-Performance Bus (AHB) 0 Advanced Peripheral Bus (APB). This bus is the legacy bus. Port C Advanced High-Performance Bus This bit defines the memory aperture for Port C. Value Description 1 PORTB R/W 0 1 Advanced High-Performance Bus (AHB) 0 Advanced Peripheral Bus (APB). This bus is the legacy bus. Port B Advanced High-Performance Bus This bit defines the memory aperture for Port B. Value Description 0 PORTA R/W 0 1 Advanced High-Performance Bus (AHB) 0 Advanced Peripheral Bus (APB). This bus is the legacy bus. Port A Advanced High-Performance Bus This bit defines the memory aperture for Port A. Value Description 1 Advanced High-Performance Bus (AHB) 0 Advanced Peripheral Bus (APB). This bus is the legacy bus. July 03, 2014 225 Texas Instruments-Production Data System Control Register 10: Run-Mode Clock Configuration 2 (RCC2), offset 0x070 This register overrides the RCC equivalent register fields, as shown in Table 5-9, when the USERCC2 bit is set, allowing the extended capabilities of the RCC2 register to be used while also providing a means to be backward-compatible to previous parts. Each RCC2 field that supersedes an RCC field is located at the same LSB bit position; however, some RCC2 fields are larger than the corresponding RCC field. Table 5-9. RCC2 Fields that Override RCC Fields RCC2 Field... Overrides RCC Field SYSDIV2, bits[28:23] SYSDIV, bits[26:23] PWRDN2, bit[13] PWRDN, bit[13] BYPASS2, bit[11] BYPASS, bit[11] OSCSRC2, bits[6:4] OSCSRC, bits[5:4] Important: Write the RCC register prior to writing the RCC2 register. If a subsequent write to the RCC register is required, include another register access after writing the RCC register and before writing the RCC2 register. Run-Mode Clock Configuration 2 (RCC2) Base 0x400F.E000 Offset 0x070 Type R/W, reset 0x07C0.6810 31 30 USERCC2 DIV400 Type Reset 29 28 27 26 reserved 25 23 22 R/W 0 R/W 0 RO 0 R/W 0 R/W 0 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 15 14 13 12 11 10 9 8 7 6 RO 0 R/W 1 R/W 1 RO 0 reserved R/W 1 RO 0 21 20 19 RO 0 RO 0 Bit/Field Name Type Reset Description 31 USERCC2 R/W 0 Use RCC2 R/W 0 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 5 4 3 2 1 0 RO 0 RO 0 OSCSRC2 RO 0 18 reserved SYSDIV2LSB reserved USBPWRDN PWRDN2 reserved BYPASS2 Type Reset 24 SYSDIV2 R/W 0 reserved R/W 1 RO 0 RO 0 Value Description 30 DIV400 R/W 0 1 The RCC2 register fields override the RCC register fields. 0 The RCC register fields are used, and the fields in RCC2 are ignored. Divide PLL as 400 MHz vs. 200 MHz This bit, along with the SYSDIV2LSB bit, allows additional frequency choices. Value Description 1 Append the SYSDIV2LSB bit to the SYSDIV2 field to create a 7 bit divisor using the 400 MHz PLL output, see Table 5-7 on page 201. 0 Use SYSDIV2 as is and apply to 200 MHz predivided PLL output. See Table 5-6 on page 200 for programming guidelines. 226 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Bit/Field Name Type Reset 29 reserved RO 0x0 28:23 SYSDIV2 R/W 0x0F Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. System Clock Divisor 2 Specifies which divisor is used to generate the system clock from either the PLL output or the oscillator source (depending on how the BYPASS2 bit is configured). SYSDIV2 is used for the divisor when both the USESYSDIV bit in the RCC register and the USERCC2 bit in this register are set. See Table 5-6 on page 200 for programming guidelines. 22 SYSDIV2LSB R/W 1 Additional LSB for SYSDIV2 When DIV400 is set, this bit becomes the LSB of SYSDIV2. If DIV400 is clear, this bit is not used. See Table 5-6 on page 200 for programming guidelines. This bit can only be set or cleared when DIV400 is set. 21:15 reserved RO 0x0 14 USBPWRDN R/W 1 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. Power-Down USB PLL Value Description 13 PWRDN2 R/W 1 1 The USB PLL is powered down. 0 The USB PLL operates normally. Power-Down PLL 2 Value Description 1 The PLL is powered down. 0 The PLL operates normally. 12 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 11 BYPASS2 R/W 1 PLL Bypass 2 Value Description 1 The system clock is derived from the OSC source and divided by the divisor specified by SYSDIV2. 0 The system clock is the PLL output clock divided by the divisor specified by SYSDIV2. See Table 5-6 on page 200 for programming guidelines. Note: 10:7 reserved RO 0x0 The ADC must be clocked from the PLL or directly from a 16-MHz clock source to operate properly. Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. July 03, 2014 227 Texas Instruments-Production Data System Control Bit/Field Name Type Reset 6:4 OSCSRC2 R/W 0x1 Description Oscillator Source 2 Selects the input source for the OSC. The values are: Value Description 0x0 MOSC Main oscillator 0x1 PIOSC Precision internal oscillator 0x2 PIOSC/4 Precision internal oscillator / 4 0x3 30 kHz 30-kHz internal oscillator 0x4-0x6 Reserved 0x7 32.768 kHz 32.768-kHz external oscillator 3:0 reserved RO 0x0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 228 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 11: Main Oscillator Control (MOSCCTL), offset 0x07C This register provides the ability to enable the MOSC clock verification circuit. When enabled, this circuit monitors the frequency of the MOSC to verify that the oscillator is operating within specified limits. If the clock goes invalid after being enabled, the microcontroller issues a power-on reset and reboots to the NMI handler. Main Oscillator Control (MOSCCTL) Base 0x400F.E000 Offset 0x07C Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 8 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 7 6 5 4 3 2 1 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 reserved Type Reset reserved Type Reset Bit/Field Name Type Reset 31:1 reserved RO 0x0000.000 0 CVAL R/W 0 RO 0 CVAL R/W 0 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. Clock Validation for MOSC Value Description 1 The MOSC monitor circuit is enabled. 0 The MOSC monitor circuit is disabled. July 03, 2014 229 Texas Instruments-Production Data System Control Register 12: Deep Sleep Clock Configuration (DSLPCLKCFG), offset 0x144 This register provides configuration information for the hardware control of Deep Sleep Mode. Deep Sleep Clock Configuration (DSLPCLKCFG) Base 0x400F.E000 Offset 0x144 Type R/W, reset 0x0780.0000 31 30 29 28 27 26 reserved Type Reset 25 24 23 22 21 20 DSDIVORIDE 18 17 16 reserved RO 0 RO 0 RO 0 R/W 0 R/W 0 R/W 1 R/W 1 R/W 1 R/W 1 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 R/W 0 R/W 0 RO 0 RO 0 RO 0 RO 0 reserved Type Reset 19 DSOSCSRC RO 0 Bit/Field Name Type Reset 31:29 reserved RO 0x0 28:23 DSDIVORIDE R/W 0x0F R/W 0 reserved Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. Divider Field Override If Deep-Sleep mode is enabled when the PLL is running, the PLL is disabled. This 6-bit field contains a system divider field that overrides the SYSDIV field in the RCC register or the SYSDIV2 field in the RCC2 register during Deep Sleep. This divider is applied to the source selected by the DSOSCSRC field. Value Description 0x0 /1 0x1 /2 0x2 /3 0x3 /4 ... ... 0x3F /64 22:7 reserved RO 0x000 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 230 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Bit/Field Name Type Reset 6:4 DSOSCSRC R/W 0x0 Description Clock Source Specifies the clock source during Deep-Sleep mode. Value Description 0x0 MOSC Use the main oscillator as the source. Note: 0x1 If the PIOSC is being used as the clock reference for the PLL, the PIOSC is the clock source instead of MOSC in Deep-Sleep mode. PIOSC Use the precision internal 16-MHz oscillator as the source. 0x2 Reserved 0x3 30 kHz Use the 30-kHz internal oscillator as the source. 0x4-0x6 Reserved 0x7 32.768 kHz Use the Hibernation module 32.768-kHz external oscillator as the source. 3:0 reserved RO 0x0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. July 03, 2014 231 Texas Instruments-Production Data System Control Register 13: Precision Internal Oscillator Calibration (PIOSCCAL), offset 0x150 This register provides the ability to update or recalibrate the precision internal oscillator. Note that a 32.768-kHz oscillator must be used as the Hibernation module clock source for the user to be able to calibrate the PIOSC. Precision Internal Oscillator Calibration (PIOSCCAL) Base 0x400F.E000 Offset 0x150 Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 R/W 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 8 RO 0 RO 0 RO 0 RO 0 RO 0 UTEN Type Reset 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 7 6 5 4 3 2 1 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 reserved reserved Type Reset 23 RO 0 CAL R/W 0 Bit/Field Name Type Reset 31 UTEN R/W 0 UPDATE reserved R/W 0 RO 0 UT Description Use User Trim Value Value Description 30:10 reserved RO 0x0000 9 CAL R/W 0 1 The trim value in bits[6:0] of this register are used for any update trim operation. 0 The factory calibration value is used for an update trim operation. Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. Start Calibration Value Description 1 Starts a new calibration of the PIOSC. Results are in the PIOSCSTAT register. The resulting trim value from the operation is active in the PIOSC after the calibration completes. The result overrides any previous update trim operation whether the calibration passes or fails. 0 No action. This bit is auto-cleared after it is set. 8 UPDATE R/W 0 Update Trim Value Description 1 Updates the PIOSC trim value with the UT bit or the DT bit in the PIOSCSTAT register. Used with UTEN. 0 No action. This bit is auto-cleared after the update. 7 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 232 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Bit/Field Name Type Reset 6:0 UT R/W 0x0 Description User Trim Value User trim value that can be loaded into the PIOSC. Refer to “Main PLL Frequency Configuration” on page 202 for more information on calibrating the PIOSC. July 03, 2014 233 Texas Instruments-Production Data System Control Register 14: Precision Internal Oscillator Statistics (PIOSCSTAT), offset 0x154 This register provides the user information on the PIOSC calibration. Note that a 32.768-kHz oscillator must be used as the Hibernation module clock source for the user to be able to calibrate the PIOSC. Precision Internal Oscillator Statistics (PIOSCSTAT) Base 0x400F.E000 Offset 0x154 Type RO, reset 0x0000.0040 31 30 29 28 RO 0 RO 0 RO 0 RO 0 15 14 13 12 RO 0 RO 0 RO 0 27 26 25 24 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 RO - RO - RO - RO - RO - RO - RO - 11 10 9 8 7 6 5 4 3 2 1 0 RO 0 RO 0 RO 0 RO 1 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 reserved Type Reset DT reserved Type Reset RO 0 RESULT reserved RO 0 RO 0 CT Bit/Field Name Type Reset Description 31:23 reserved RO 0x00 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 22:16 DT RO - Default Trim Value This field contains the default trim value. This value is loaded into the PIOSC after every full power-up. 15:10 reserved RO 0x0 9:8 RESULT RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. Calibration Result Value Description 7 reserved RO 0 6:0 CT RO 0x40 0x0 Calibration has not been attempted. 0x1 The last calibration operation completed to meet 1% accuracy. 0x2 The last calibration operation failed to meet 1% accuracy. 0x3 Reserved Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. Calibration Trim Value This field contains the trim value from the last calibration operation. After factory calibration CT and DT are the same. 234 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 15: I2S MCLK Configuration (I2SMCLKCFG), offset 0x170 This register configures the receive and transmit fractional clock dividers for the for the I2S master transmit and receive clocks (I2S0TXMCLK and I2S0RXMCLK). Varying the integer and fractional inputs for the clocks allows greater accuracy in hitting the target I2S clock frequencies. Refer to “Clock Control” on page 858 for combinations of the TXI and TXF bits and the RXI and RXF bits that provide MCLK frequencies within acceptable error limits. I2S MCLK Configuration (I2SMCLKCFG) Base 0x400F.E000 Offset 0x170 Type R/W, reset 0x0000.0000 Type Reset Type Reset 31 30 RXEN reserved R/W 0 RO 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 13 12 11 10 9 15 14 TXEN reserved R/W 0 RO 0 29 28 27 26 25 24 23 22 21 20 19 18 RXI R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 8 7 6 5 4 3 2 TXI R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 Bit/Field Name Type Reset 31 RXEN R/W 0 17 16 R/W 0 R/W 0 1 0 R/W 0 R/W 0 RXF TXF R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 Description RX Clock Enable Value Description 1 The I2S receive clock generator is enabled. 0 The I2S receive clock generator is disabled. If the RXSLV bit in the I2S Module Configuration (I2SCFG) register is set, then the I2S0RXMCLK must be externally generated. 30 reserved RO 0 29:20 RXI R/W 0x0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. RX Clock Integer Input This field contains the integer input for the receive clock generator. 19:16 RXF R/W 0x0 RX Clock Fractional Input This field contains the fractional input for the receive clock generator. 15 TXEN R/W 0 TX Clock Enable Value Description 1 The I2S transmit clock generator is enabled. 0 The I2S transmit clock generator is disabled. If the TXSLV bit in the I2S Module Configuration (I2SCFG) register is set, then the I2S0TXMCLK must be externally generated. July 03, 2014 235 Texas Instruments-Production Data System Control Bit/Field Name Type Reset 14 reserved RO 0 13:4 TXI R/W 0x00 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. TX Clock Integer Input This field contains the integer input for the transmit clock generator. 3:0 TXF R/W 0x0 TX Clock Fractional Input This field contains the fractional input for the transmit clock generator. 236 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 16: Device Identification 1 (DID1), offset 0x004 This register identifies the device family, part number, temperature range, pin count, and package type. Each microcontroller is uniquely identified by the combined values of the CLASS field in the DID0 register and the PARTNO field in the DID1 register. Device Identification 1 (DID1) Base 0x400F.E000 Offset 0x004 Type RO, reset 31 30 29 28 27 26 RO 0 15 25 24 23 22 21 20 RO 0 RO 0 RO 1 RO 0 RO 0 RO 0 RO 0 RO 0 RO 1 RO 1 RO 1 14 13 12 11 10 9 8 7 6 5 4 RO 0 RO 0 RO 0 RO 0 RO 0 RO - RO - RO - VER Type Reset FAM PINCOUNT Type Reset RO 0 RO 1 18 17 16 RO 1 RO 1 RO 0 RO 1 3 2 1 0 PARTNO reserved RO 0 19 TEMP Bit/Field Name Type Reset 31:28 VER RO 0x1 RO - PKG ROHS RO - RO 1 QUAL RO - RO - Description DID1 Version This field defines the DID1 register format version. The version number is numeric. The value of the VER field is encoded as follows (all other encodings are reserved): Value Description 0x1 27:24 FAM RO 0x0 Second version of the DID1 register format. Family This field provides the family identification of the device within the Luminary Micro product portfolio. The value is encoded as follows (all other encodings are reserved): Value Description 0x0 23:16 PARTNO RO 0x7D Stellaris family of microcontollers, that is, all devices with external part numbers starting with LM3S. Part Number This field provides the part number of the device within the family. The value is encoded as follows (all other encodings are reserved): Value Description 0x7D LM3S9U90 15:13 PINCOUNT RO 0x2 Package Pin Count This field specifies the number of pins on the device package. The value is encoded as follows (all other encodings are reserved): Value Description 0x2 100-pin package July 03, 2014 237 Texas Instruments-Production Data System Control Bit/Field Name Type Reset Description 12:8 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 7:5 TEMP RO - Temperature Range This field specifies the temperature rating of the device. The value is encoded as follows (all other encodings are reserved): Value Description 4:3 PKG RO - 0x0 Commercial temperature range (0°C to 70°C) 0x1 Industrial temperature range (-40°C to 85°C) 0x2 Extended temperature range (-40°C to 105°C) Package Type This field specifies the package type. The value is encoded as follows (all other encodings are reserved): Value Description 2 ROHS RO 1 0x0 SOIC package 0x1 LQFP package 0x2 BGA package RoHS-Compliance This bit specifies whether the device is RoHS-compliant. A 1 indicates the part is RoHS-compliant. 1:0 QUAL RO - Qualification Status This field specifies the qualification status of the device. The value is encoded as follows (all other encodings are reserved): Value Description 0x0 Engineering Sample (unqualified) 0x1 Pilot Production (unqualified) 0x2 Fully Qualified 238 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 17: Device Capabilities 0 (DC0), offset 0x008 This register is predefined by the part and can be used to verify features. Device Capabilities 0 (DC0) Base 0x400F.E000 Offset 0x008 Type RO, reset 0x017F.00BF 31 30 29 28 27 26 25 24 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 1 15 14 13 12 11 10 9 8 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 23 22 21 20 19 18 17 16 RO 0 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 7 6 5 4 3 2 1 0 RO 0 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 SRAMSZ Type Reset FLASHSZ Type Reset RO 1 Bit/Field Name Type Reset Description 31:16 SRAMSZ RO 0x017F SRAM Size Indicates the size of the on-chip SRAM memory. Value Description 0x017F 96 KB of SRAM 15:0 FLASHSZ RO 0x00BF Flash Size Indicates the size of the on-chip flash memory. Value Description 0x00BF 384 KB of Flash July 03, 2014 239 Texas Instruments-Production Data System Control Register 18: Device Capabilities 1 (DC1), offset 0x010 This register is predefined by the part and can be used to verify features. If any bit is clear in this register, the module is not present. The corresponding bit in the RCGC0, SCGC0, and DCGC0 registers cannot be set. Device Capabilities 1 (DC1) Base 0x400F.E000 Offset 0x010 Type RO, reset 31 30 29 reserved Type Reset 28 WDT1 26 24 23 22 21 20 19 18 16 CAN1 CAN0 ADC1 ADC0 RO 0 RO 1 RO 0 RO 0 RO 1 RO 1 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 1 RO 1 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 MPU HIB TEMPSNS PLL WDT0 SWO SWD JTAG RO - RO - RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO - MAXADC1SPD MAXADC0SPD RO 1 RO 1 RO 1 RO 1 reserved 17 RO 0 RO - reserved 25 RO 0 MINSYSDIV Type Reset 27 Bit/Field Name Type Reset Description 31:29 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 28 WDT1 RO 1 Watchdog Timer 1 Present When set, indicates that watchdog timer 1 is present. 27:26 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 25 CAN1 RO 1 CAN Module 1 Present When set, indicates that CAN unit 1 is present. 24 CAN0 RO 1 CAN Module 0 Present When set, indicates that CAN unit 0 is present. 23:18 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 17 ADC1 RO 1 ADC Module 1 Present When set, indicates that ADC module 1 is present. 16 ADC0 RO 1 ADC Module 0 Present When set, indicates that ADC module 0 is present 240 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Bit/Field Name Type Reset 15:12 MINSYSDIV RO - Description System Clock Divider Minimum 4-bit divider value for system clock. The reset value is hardware-dependent. See the RCC register for how to change the system clock divisor using the SYSDIV bit. Value Description 11:10 MAXADC1SPD RO 0x3 0x1 Specifies an 80-MHz CPU clock with a PLL divider of 2.5. 0x2 Specifies a 66.67-MHz CPU clock with a PLL divider of 3. 0x3 Specifies a 50-MHz CPU clock with a PLL divider of 4. 0x7 Specifies a 25-MHz clock with a PLL divider of 8. 0x9 Specifies a 20-MHz clock with a PLL divider of 10. Max ADC1 Speed This field indicates the maximum rate at which the ADC samples data. Value Description 0x3 9:8 MAXADC0SPD RO 0x3 1M samples/second Max ADC0 Speed This field indicates the maximum rate at which the ADC samples data. Value Description 0x3 7 MPU RO 1 1M samples/second MPU Present When set, indicates that the Cortex-M3 Memory Protection Unit (MPU) module is present. See the "Cortex-M3 Peripherals" chapter for details on the MPU. 6 HIB RO 1 Hibernation Module Present When set, indicates that the Hibernation module is present. 5 TEMPSNS RO 1 Temp Sensor Present When set, indicates that the on-chip temperature sensor is present. 4 PLL RO 1 PLL Present When set, indicates that the on-chip Phase Locked Loop (PLL) is present. 3 WDT0 RO 1 Watchdog Timer 0 Present When set, indicates that watchdog timer 0 is present. 2 SWO RO 1 SWO Trace Port Present When set, indicates that the Serial Wire Output (SWO) trace port is present. 1 SWD RO 1 SWD Present When set, indicates that the Serial Wire Debugger (SWD) is present. 0 JTAG RO 1 JTAG Present When set, indicates that the JTAG debugger interface is present. July 03, 2014 241 Texas Instruments-Production Data System Control Register 19: Device Capabilities 2 (DC2), offset 0x014 This register is predefined by the part and can be used to verify features. If any bit is clear in this register, the module is not present. The corresponding bit in the RCGC0, SCGC0, and DCGC0 registers cannot be set. Device Capabilities 2 (DC2) Base 0x400F.E000 Offset 0x014 Type RO, reset 0x570F.5037 Type Reset Type Reset 31 30 29 28 27 26 25 24 23 22 reserved EPI0 reserved I2S0 reserved COMP2 COMP1 COMP0 RO 0 RO 1 RO 0 RO 1 RO 0 RO 1 RO 1 15 14 13 12 11 10 9 reserved I2C1 reserved I2C0 RO 0 RO 1 RO 0 RO 1 RO 0 RO 0 RO 0 21 20 19 18 17 16 RO 1 RO 0 RO 0 RO 0 RO 0 TIMER3 TIMER2 TIMER1 TIMER0 RO 1 RO 1 RO 1 RO 1 8 7 6 5 4 3 2 1 0 RO 0 RO 0 RO 0 SSI1 SSI0 reserved UART2 UART1 UART0 RO 1 RO 1 RO 0 RO 1 RO 1 RO 1 reserved reserved Bit/Field Name Type Reset Description 31 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 30 EPI0 RO 1 EPI Module 0 Present When set, indicates that EPI module 0 is present. 29 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 28 I2S0 RO 1 I2S Module 0 Present When set, indicates that I2S module 0 is present. 27 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 26 COMP2 RO 1 Analog Comparator 2 Present When set, indicates that analog comparator 2 is present. 25 COMP1 RO 1 Analog Comparator 1 Present When set, indicates that analog comparator 1 is present. 24 COMP0 RO 1 Analog Comparator 0 Present When set, indicates that analog comparator 0 is present. 23:20 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 19 TIMER3 RO 1 Timer Module 3 Present When set, indicates that General-Purpose Timer module 3 is present. 18 TIMER2 RO 1 Timer Module 2 Present When set, indicates that General-Purpose Timer module 2 is present. 242 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Bit/Field Name Type Reset 17 TIMER1 RO 1 Description Timer Module 1 Present When set, indicates that General-Purpose Timer module 1 is present. 16 TIMER0 RO 1 Timer Module 0 Present When set, indicates that General-Purpose Timer module 0 is present. 15 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 14 I2C1 RO 1 I2C Module 1 Present When set, indicates that I2C module 1 is present. 13 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 12 I2C0 RO 1 I2C Module 0 Present When set, indicates that I2C module 0 is present. 11:6 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 5 SSI1 RO 1 SSI Module 1 Present When set, indicates that SSI module 1 is present. 4 SSI0 RO 1 SSI Module 0 Present When set, indicates that SSI module 0 is present. 3 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 2 UART2 RO 1 UART Module 2 Present When set, indicates that UART module 2 is present. 1 UART1 RO 1 UART Module 1 Present When set, indicates that UART module 1 is present. 0 UART0 RO 1 UART Module 0 Present When set, indicates that UART module 0 is present. July 03, 2014 243 Texas Instruments-Production Data System Control Register 20: Device Capabilities 3 (DC3), offset 0x018 This register is predefined by the part and can be used to verify features. If any bit is clear in this register, the module is not present. The corresponding bit in the RCGC0, SCGC0, and DCGC0 registers cannot be set. Device Capabilities 3 (DC3) Base 0x400F.E000 Offset 0x018 Type RO, reset 0xBFFF.7FC0 Type Reset Type Reset 31 30 29 28 27 26 25 24 32KHZ reserved CCP5 CCP4 CCP3 CCP2 CCP1 CCP0 RO 1 RO 0 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 reserved C2O RO 0 RO 1 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 C2PLUS C2MINUS RO 1 RO 1 C1O C1PLUS C1MINUS RO 1 RO 1 RO 1 Bit/Field Name Type Reset 31 32KHZ RO 1 C0O RO 1 23 22 21 20 19 18 17 16 ADC0AIN7 ADC0AIN6 ADC0AIN5 ADC0AIN4 ADC0AIN3 ADC0AIN2 ADC0AIN1 ADC0AIN0 C0PLUS C0MINUS RO 1 RO 1 reserved Description 32KHz Input Clock Available When set, indicates an even CCP pin is present and can be used as a 32-KHz input clock. 30 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 29 CCP5 RO 1 CCP5 Pin Present When set, indicates that Capture/Compare/PWM pin 5 is present. 28 CCP4 RO 1 CCP4 Pin Present When set, indicates that Capture/Compare/PWM pin 4 is present. 27 CCP3 RO 1 CCP3 Pin Present When set, indicates that Capture/Compare/PWM pin 3 is present. 26 CCP2 RO 1 CCP2 Pin Present When set, indicates that Capture/Compare/PWM pin 2 is present. 25 CCP1 RO 1 CCP1 Pin Present When set, indicates that Capture/Compare/PWM pin 1 is present. 24 CCP0 RO 1 CCP0 Pin Present When set, indicates that Capture/Compare/PWM pin 0 is present. 23 ADC0AIN7 RO 1 ADC Module 0 AIN7 Pin Present When set, indicates that ADC module 0 input pin 7 is present. 22 ADC0AIN6 RO 1 ADC Module 0 AIN6 Pin Present When set, indicates that ADC module 0 input pin 6 is present. 21 ADC0AIN5 RO 1 ADC Module 0 AIN5 Pin Present When set, indicates that ADC module 0 input pin 5 is present. 244 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Bit/Field Name Type Reset 20 ADC0AIN4 RO 1 Description ADC Module 0 AIN4 Pin Present When set, indicates that ADC module 0 input pin 4 is present. 19 ADC0AIN3 RO 1 ADC Module 0 AIN3 Pin Present When set, indicates that ADC module 0 input pin 3 is present. 18 ADC0AIN2 RO 1 ADC Module 0 AIN2 Pin Present When set, indicates that ADC module 0 input pin 2 is present. 17 ADC0AIN1 RO 1 ADC Module 0 AIN1 Pin Present When set, indicates that ADC module 0 input pin 1 is present. 16 ADC0AIN0 RO 1 ADC Module 0 AIN0 Pin Present When set, indicates that ADC module 0 input pin 0 is present. 15 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 14 C2O RO 1 C2o Pin Present When set, indicates that the analog comparator 2 output pin is present. 13 C2PLUS RO 1 C2+ Pin Present When set, indicates that the analog comparator 2 (+) input pin is present. 12 C2MINUS RO 1 C2- Pin Present When set, indicates that the analog comparator 2 (-) input pin is present. 11 C1O RO 1 C1o Pin Present When set, indicates that the analog comparator 1 output pin is present. 10 C1PLUS RO 1 C1+ Pin Present When set, indicates that the analog comparator 1 (+) input pin is present. 9 C1MINUS RO 1 C1- Pin Present When set, indicates that the analog comparator 1 (-) input pin is present. 8 C0O RO 1 C0o Pin Present When set, indicates that the analog comparator 0 output pin is present. 7 C0PLUS RO 1 C0+ Pin Present When set, indicates that the analog comparator 0 (+) input pin is present. 6 C0MINUS RO 1 C0- Pin Present When set, indicates that the analog comparator 0 (-) input pin is present. 5:0 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. July 03, 2014 245 Texas Instruments-Production Data System Control Register 21: Device Capabilities 4 (DC4), offset 0x01C This register is predefined by the part and can be used to verify features. If any bit is clear in this register, the module is not present. The corresponding bit in the RCGC0, SCGC0, and DCGC0 registers cannot be set. Device Capabilities 4 (DC4) Base 0x400F.E000 Offset 0x01C Type RO, reset 0x5004.F1FF Type Reset Type Reset 31 30 29 28 27 26 25 24 reserved EPHY0 reserved EMAC0 RO 0 RO 1 RO 0 RO 1 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 CCP7 RO 1 CCP6 UDMA ROM RO 1 RO 1 RO 1 23 22 21 20 19 RO 0 RO 0 RO 0 RO 0 RO 0 RO 1 RO 0 RO 0 8 7 6 5 4 3 2 1 0 GPIOJ GPIOH GPIOG GPIOF GPIOE GPIOD GPIOC GPIOB GPIOA RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 reserved reserved RO 0 RO 0 RO 0 18 17 PICAL 16 reserved Bit/Field Name Type Reset Description 31 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 30 EPHY0 RO 1 Ethernet PHY Layer 0 Present When set, indicates that Ethernet PHY layer 0 is present. 29 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 28 EMAC0 RO 1 Ethernet MAC Layer 0 Present When set, indicates that Ethernet MAC layer 0 is present. 27:19 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 18 PICAL RO 1 PIOSC Calibrate When set, indicates that the PIOSC can be calibrated. 17:16 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 15 CCP7 RO 1 CCP7 Pin Present When set, indicates that Capture/Compare/PWM pin 7 is present. 14 CCP6 RO 1 CCP6 Pin Present When set, indicates that Capture/Compare/PWM pin 6 is present. 13 UDMA RO 1 Micro-DMA Module Present When set, indicates that the micro-DMA module present. 12 ROM RO 1 Internal Code ROM Present When set, indicates that internal code ROM is present. 246 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Bit/Field Name Type Reset Description 11:9 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 8 GPIOJ RO 1 GPIO Port J Present When set, indicates that GPIO Port J is present. 7 GPIOH RO 1 GPIO Port H Present When set, indicates that GPIO Port H is present. 6 GPIOG RO 1 GPIO Port G Present When set, indicates that GPIO Port G is present. 5 GPIOF RO 1 GPIO Port F Present When set, indicates that GPIO Port F is present. 4 GPIOE RO 1 GPIO Port E Present When set, indicates that GPIO Port E is present. 3 GPIOD RO 1 GPIO Port D Present When set, indicates that GPIO Port D is present. 2 GPIOC RO 1 GPIO Port C Present When set, indicates that GPIO Port C is present. 1 GPIOB RO 1 GPIO Port B Present When set, indicates that GPIO Port B is present. 0 GPIOA RO 1 GPIO Port A Present When set, indicates that GPIO Port A is present. July 03, 2014 247 Texas Instruments-Production Data System Control Register 22: Device Capabilities 5 (DC5), offset 0x020 This register is predefined by the part and can be used to verify features. If any bit is clear in this register, the module is not present. The corresponding bit in the RCGC0, SCGC0, and DCGC0 registers cannot be set. Device Capabilities 5 (DC5) Base 0x400F.E000 Offset 0x020 Type RO, reset 0x0000.0000 31 30 29 28 27 26 25 24 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 8 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 7 6 5 4 3 2 1 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 reserved Type Reset reserved Type Reset Bit/Field Name Type Reset 31:0 reserved RO 0 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 248 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 23: Device Capabilities 6 (DC6), offset 0x024 This register is predefined by the part and can be used to verify features. If any bit is clear in this register, the module is not present. The corresponding bit in the RCGC0, SCGC0, and DCGC0 registers cannot be set. Device Capabilities 6 (DC6) Base 0x400F.E000 Offset 0x024 Type RO, reset 0x0000.0013 31 30 29 28 27 26 25 24 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 8 7 6 5 4 3 2 1 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 1 reserved Type Reset reserved Type Reset RO 0 USB0PHY RO 1 reserved RO 0 USB0 RO 1 Bit/Field Name Type Reset Description 31:5 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 4 USB0PHY RO 1 USB Module 0 PHY Present When set, indicates that the USB module 0 PHY is present. 3:2 reserved RO 0 1:0 USB0 RO 0x3 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. USB Module 0 Present Thie field indicates that USB module 0 is present and specifies its capability. Value Description 0x3 USB0 is OTG. July 03, 2014 249 Texas Instruments-Production Data System Control Register 24: Device Capabilities 7 (DC7), offset 0x028 This register is predefined by the part and can be used to verify uDMA channel features. A 1 indicates the channel is available on this device; a 0 that the channel is only available on other devices in the family. Most channels have primary and secondary assignments. If the primary function is not available on this microcontroller, the secondary function becomes the primary function. If the secondary function is not available, the primary function is the only option. Device Capabilities 7 (DC7) Base 0x400F.E000 Offset 0x028 Type RO, reset 0xFFFF.FFFF 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 reserved DMACH30 DMACH29 DMACH28 DMACH27 DMACH26 DMACH25 DMACH24 DMACH23 DMACH22 DMACH21 DMACH20 DMACH19 DMACH18 DMACH17 DMACH16 Type Reset RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 DMACH15 DMACH14 DMACH13 DMACH12 DMACH11 DMACH10 DMACH9 DMACH8 DMACH7 DMACH6 DMACH5 DMACH4 DMACH3 DMACH2 DMACH1 DMACH0 Type Reset RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 Bit/Field Name Type Reset 31 reserved RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 Description Reserved Reserved for uDMA channel 31. 30 DMACH30 RO 1 SW When set, indicates uDMA channel 30 is available for software transfers. 29 DMACH29 RO 1 I2S0_TX / CAN1_TX When set, indicates uDMA channel 29 is available and connected to the transmit path of I2S module 0. If the corresponding bit in the DMACHASGN register is set, the channel is connected instead to the secondary channel assignment of CAN module 1 transmit. 28 DMACH28 RO 1 I2S0_RX / CAN1_RX When set, indicates uDMA channel 28 is available and connected to the receive path of I2S module 0. If the corresponding bit in the DMACHASGN register is set, the channel is connected instead to the secondary channel assignment of CAN module 1 receive. 27 DMACH27 RO 1 CAN1_TX / ADC1_SS3 When set, indicates uDMA channel 27 is available and connected to the transmit path of CAN module 1. If the corresponding bit in the DMACHASGN register is set, the channel is connected instead to the secondary channel assignment of ADC module 1 Sample Sequencer 3. 26 DMACH26 RO 1 CAN1_RX / ADC1_SS2 When set, indicates uDMA channel 26 is available and connected to the receive path of CAN module 1. If the corresponding bit in the DMACHASGN register is set, the channel is connected instead to the secondary channel assignment of ADC module 1 Sample Sequencer 2. 250 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Bit/Field Name Type Reset 25 DMACH25 RO 1 Description SSI1_TX / ADC1_SS1 When set, indicates uDMA channel 25 is available and connected to the transmit path of SSI module 1. If the corresponding bit in the DMACHASGN register is set, the channel is connected instead to the secondary channel assignment of ADC module 1 Sample Sequencer 1. 24 DMACH24 RO 1 SSI1_RX / ADC1_SS0 When set, indicates uDMA channel 24 is available and connected to the receive path of SSI module 1. If the corresponding bit in the DMACHASGN register is set, the channel is connected instead to the secondary channel assignment of ADC module 1 Sample Sequencer 0. 23 DMACH23 RO 1 UART1_TX / CAN2_TX When set, indicates uDMA channel 23 is available and connected to the transmit path of UART module 1. If the corresponding bit in the DMACHASGN register is set, the channel is connected instead to the secondary channel assignment of CAN module 2 transmit. 22 DMACH22 RO 1 UART1_RX / CAN2_RX When set, indicates uDMA channel 22 is available and connected to the receive path of UART module 1. If the corresponding bit in the DMACHASGN register is set, the channel is connected instead to the secondary channel assignment of CAN module 2 receive. 21 DMACH21 RO 1 Timer1B / EPI0_WFIFO When set, indicates uDMA channel 21 is available and connected to Timer 1B. If the corresponding bit in the DMACHASGN register is set, the channel is connected instead to the secondary channel assignment of EPI module 0 write FIFO (WRIFO). 20 DMACH20 RO 1 Timer1A / EPI0_NBRFIFO When set, indicates uDMA channel 20 is available and connected to Timer 1A. If the corresponding bit in the DMACHASGN register is set, the channel is connected instead to the secondary channel assignment of EPI module 0 non-blocking read FIFO (NBRFIFO). 19 DMACH19 RO 1 Timer0B / Timer1B When set, indicates uDMA channel 19 is available and connected to Timer 0B. If the corresponding bit in the DMACHASGN register is set, the channel is connected instead to the secondary channel assignment of Timer 1B. 18 DMACH18 RO 1 Timer0A / Timer1A When set, indicates uDMA channel 18 is available and connected to Timer 0A. If the corresponding bit in the DMACHASGN register is set, the channel is connected instead to the secondary channel assignment of Timer 1A. 17 DMACH17 RO 1 ADC0_SS3 When set, indicates uDMA channel 17 is available and connected to ADC module 0 Sample Sequencer 3. 16 DMACH16 RO 1 ADC0_SS2 When set, indicates uDMA channel 16 is available and connected to ADC module 0 Sample Sequencer 2. July 03, 2014 251 Texas Instruments-Production Data System Control Bit/Field Name Type Reset 15 DMACH15 RO 1 Description ADC0_SS1 / Timer2B When set, indicates uDMA channel 15 is available and connected to ADC module 0 Sample Sequencer 1. If the corresponding bit in the DMACHASGN register is set, the channel is connected instead to the secondary channel assignment of Timer 2B. 14 DMACH14 RO 1 ADC0_SS0 / Timer2A When set, indicates uDMA channel 14 is available and connected to ADC module 0 Sample Sequencer 0. If the corresponding bit in the DMACHASGN register is set, the channel is connected instead to the secondary channel assignment of Timer 2A. 13 DMACH13 RO 1 CAN0_TX / UART2_TX When set, indicates uDMA channel 13 is available and connected to the transmit path of CAN module 0. If the corresponding bit in the DMACHASGN register is set, the channel is connected instead to the secondary channel assignment of UART module 2 transmit. 12 DMACH12 RO 1 CAN0_RX / UART2_RX When set, indicates uDMA channel 12 is available and connected to the receive path of CAN module 0. If the corresponding bit in the DMACHASGN register is set, the channel is connected instead to the secondary channel assignment of UART module 2 receive. 11 DMACH11 RO 1 SSI0_TX / SSI1_TX When set, indicates uDMA channel 11 is available and connected to the transmit path of SSI module 0. If the corresponding bit in the DMACHASGN register is set, the channel is connected instead to the secondary channel assignment of SSI module 1 transmit. 10 DMACH10 RO 1 SSI0_RX / SSI1_RX When set, indicates uDMA channel 10 is available and connected to the receive path of SSI module 0. If the corresponding bit in the DMACHASGN register is set, the channel is connected instead to the secondary channel assignment of SSI module 1 receive. 9 DMACH9 RO 1 UART0_TX / UART1_TX When set, indicates uDMA channel 9 is available and connected to the transmit path of UART module 0. If the corresponding bit in the DMACHASGN register is set, the channel is connected instead to the secondary channel assignment of UART module 1 transmit. 8 DMACH8 RO 1 UART0_RX / UART1_RX When set, indicates uDMA channel 8 is available and connected to the receive path of UART module 0. If the corresponding bit in the DMACHASGN register is set, the channel is connected instead to the secondary channel assignment of UART module 1 receive. 7 DMACH7 RO 1 ETH_TX / Timer2B When set, indicates uDMA channel 7 is available and connected to the transmit path of the Ethernet module. If the corresponding bit in the DMACHASGN register is set, the channel is connected instead to the secondary channel assignment of Timer 2B. 252 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Bit/Field Name Type Reset 6 DMACH6 RO 1 Description ETH_RX / Timer2A When set, indicates uDMA channel 6 is available and connected to the receive path of the Ethernet module. If the corresponding bit in the DMACHASGN register is set, the channel is connected instead to the secondary channel assignment of Timer 2A. 5 DMACH5 RO 1 USB_EP3_TX / Timer2B When set, indicates uDMA channel 5 is available and connected to the transmit path of USB endpoint 3. If the corresponding bit in the DMACHASGN register is set, the channel is connected instead to the secondary channel assignment of Timer 2B. 4 DMACH4 RO 1 USB_EP3_RX / Timer2A When set, indicates uDMA channel 4 is available and connected to the receive path of USB endpoint 3. If the corresponding bit in the DMACHASGN register is set, the channel is connected instead to the secondary channel assignment of Timer 2A. 3 DMACH3 RO 1 USB_EP2_TX / Timer3B When set, indicates uDMA channel 3 is available and connected to the transmit path of USB endpoint 2. If the corresponding bit in the DMACHASGN register is set, the channel is connected instead to the secondary channel assignment of Timer 3B. 2 DMACH2 RO 1 USB_EP2_RX / Timer3A When set, indicates uDMA channel 2 is available and connected to the receive path of USB endpoint 2. If the corresponding bit in the DMACHASGN register is set, the channel is connected instead to the secondary channel assignment of Timer 3A. 1 DMACH1 RO 1 USB_EP1_TX / UART2_TX When set, indicates uDMA channel 1 is available and connected to the transmit path of USB endpoint 1. If the corresponding bit in the DMACHASGN register is set, the channel is connected instead to the secondary channel assignment of UART module 2 transmit. 0 DMACH0 RO 1 USB_EP1_RX / UART2_RX When set, indicates uDMA channel 0 is available and connected to the receive path of USB endpoint 1. If the corresponding bit in the DMACHASGN register is set, the channel is connected instead to the secondary channel assignment of UART module 2 receive. July 03, 2014 253 Texas Instruments-Production Data System Control Register 25: Device Capabilities 8 ADC Channels (DC8), offset 0x02C This register is predefined by the part and can be used to verify features. Device Capabilities 8 ADC Channels (DC8) Base 0x400F.E000 Offset 0x02C Type RO, reset 0xFFFF.FFFF Type Reset Type Reset 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 ADC1AIN15 ADC1AIN14 ADC1AIN13 ADC1AIN12 ADC1AIN11 ADC1AIN10 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 ADC0AIN15 ADC0AIN14 ADC0AIN13 ADC0AIN12 ADC0AIN11 ADC0AIN10 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 ADC1AIN9 ADC1AIN8 ADC1AIN7 ADC1AIN6 ADC1AIN5 ADC1AIN4 ADC1AIN3 ADC1AIN2 ADC1AIN1 ADC1AIN0 ADC0AIN9 ADC0AIN8 ADC0AIN7 ADC0AIN6 ADC0AIN5 ADC0AIN4 ADC0AIN3 ADC0AIN2 ADC0AIN1 ADC0AIN0 RO 1 Bit/Field Name Type Reset 31 ADC1AIN15 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 Description ADC Module 1 AIN15 Pin Present When set, indicates that ADC module 1 input pin 15 is present. 30 ADC1AIN14 RO 1 ADC Module 1 AIN14 Pin Present When set, indicates that ADC module 1 input pin 14 is present. 29 ADC1AIN13 RO 1 ADC Module 1 AIN13 Pin Present When set, indicates that ADC module 1 input pin 13 is present. 28 ADC1AIN12 RO 1 ADC Module 1 AIN12 Pin Present When set, indicates that ADC module 1 input pin 12 is present. 27 ADC1AIN11 RO 1 ADC Module 1 AIN11 Pin Present When set, indicates that ADC module 1 input pin 11 is present. 26 ADC1AIN10 RO 1 ADC Module 1 AIN10 Pin Present When set, indicates that ADC module 1 input pin 10 is present. 25 ADC1AIN9 RO 1 ADC Module 1 AIN9 Pin Present When set, indicates that ADC module 1 input pin 9 is present. 24 ADC1AIN8 RO 1 ADC Module 1 AIN8 Pin Present When set, indicates that ADC module 1 input pin 8 is present. 23 ADC1AIN7 RO 1 ADC Module 1 AIN7 Pin Present When set, indicates that ADC module 1 input pin 7 is present. 22 ADC1AIN6 RO 1 ADC Module 1 AIN6 Pin Present When set, indicates that ADC module 1 input pin 6 is present. 21 ADC1AIN5 RO 1 ADC Module 1 AIN5 Pin Present When set, indicates that ADC module 1 input pin 5 is present. 20 ADC1AIN4 RO 1 ADC Module 1 AIN4 Pin Present When set, indicates that ADC module 1 input pin 4 is present. 254 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Bit/Field Name Type Reset 19 ADC1AIN3 RO 1 Description ADC Module 1 AIN3 Pin Present When set, indicates that ADC module 1 input pin 3 is present. 18 ADC1AIN2 RO 1 ADC Module 1 AIN2 Pin Present When set, indicates that ADC module 1 input pin 2 is present. 17 ADC1AIN1 RO 1 ADC Module 1 AIN1 Pin Present When set, indicates that ADC module 1 input pin 1 is present. 16 ADC1AIN0 RO 1 ADC Module 1 AIN0 Pin Present When set, indicates that ADC module 1 input pin 0 is present. 15 ADC0AIN15 RO 1 ADC Module 0 AIN15 Pin Present When set, indicates that ADC module 0 input pin 15 is present. 14 ADC0AIN14 RO 1 ADC Module 0 AIN14 Pin Present When set, indicates that ADC module 0 input pin 14 is present. 13 ADC0AIN13 RO 1 ADC Module 0 AIN13 Pin Present When set, indicates that ADC module 0 input pin 13 is present. 12 ADC0AIN12 RO 1 ADC Module 0 AIN12 Pin Present When set, indicates that ADC module 0 input pin 12 is present. 11 ADC0AIN11 RO 1 ADC Module 0 AIN11 Pin Present When set, indicates that ADC module 0 input pin 11 is present. 10 ADC0AIN10 RO 1 ADC Module 0 AIN10 Pin Present When set, indicates that ADC module 0 input pin 10 is present. 9 ADC0AIN9 RO 1 ADC Module 0 AIN9 Pin Present When set, indicates that ADC module 0 input pin 9 is present. 8 ADC0AIN8 RO 1 ADC Module 0 AIN8 Pin Present When set, indicates that ADC module 0 input pin 8 is present. 7 ADC0AIN7 RO 1 ADC Module 0 AIN7 Pin Present When set, indicates that ADC module 0 input pin 7 is present. 6 ADC0AIN6 RO 1 ADC Module 0 AIN6 Pin Present When set, indicates that ADC module 0 input pin 6 is present. 5 ADC0AIN5 RO 1 ADC Module 0 AIN5 Pin Present When set, indicates that ADC module 0 input pin 5 is present. 4 ADC0AIN4 RO 1 ADC Module 0 AIN4 Pin Present When set, indicates that ADC module 0 input pin 4 is present. 3 ADC0AIN3 RO 1 ADC Module 0 AIN3 Pin Present When set, indicates that ADC module 0 input pin 3 is present. 2 ADC0AIN2 RO 1 ADC Module 0 AIN2 Pin Present When set, indicates that ADC module 0 input pin 2 is present. July 03, 2014 255 Texas Instruments-Production Data System Control Bit/Field Name Type Reset 1 ADC0AIN1 RO 1 Description ADC Module 0 AIN1 Pin Present When set, indicates that ADC module 0 input pin 1 is present. 0 ADC0AIN0 RO 1 ADC Module 0 AIN0 Pin Present When set, indicates that ADC module 0 input pin 0 is present. 256 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 26: Device Capabilities 9 ADC Digital Comparators (DC9), offset 0x190 This register is predefined by the part and can be used to verify features. Device Capabilities 9 ADC Digital Comparators (DC9) Base 0x400F.E000 Offset 0x190 Type RO, reset 0x00FF.00FF 31 30 29 28 27 26 25 24 reserved Type Reset RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 8 reserved Type Reset RO 0 RO 0 RO 0 RO 0 23 22 21 20 19 18 17 16 ADC1DC7 ADC1DC6 ADC1DC5 ADC1DC4 ADC1DC3 ADC1DC2 ADC1DC1 ADC1DC0 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 7 6 5 4 3 2 1 0 ADC0DC7 ADC0DC6 ADC0DC5 ADC0DC4 ADC0DC3 ADC0DC2 ADC0DC1 ADC0DC0 RO 0 RO 0 RO 0 RO 0 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 Bit/Field Name Type Reset Description 31:24 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 23 ADC1DC7 RO 1 ADC1 DC7 Present When set, indicates that ADC module 1 Digital Comparator 7 is present. 22 ADC1DC6 RO 1 ADC1 DC6 Present When set, indicates that ADC module 1 Digital Comparator 6 is present. 21 ADC1DC5 RO 1 ADC1 DC5 Present When set, indicates that ADC module 1 Digital Comparator 5 is present. 20 ADC1DC4 RO 1 ADC1 DC4 Present When set, indicates that ADC module 1 Digital Comparator 4 is present. 19 ADC1DC3 RO 1 ADC1 DC3 Present When set, indicates that ADC module 1 Digital Comparator 3 is present. 18 ADC1DC2 RO 1 ADC1 DC2 Present When set, indicates that ADC module 1 Digital Comparator 2 is present. 17 ADC1DC1 RO 1 ADC1 DC1 Present When set, indicates that ADC module 1 Digital Comparator 1 is present. 16 ADC1DC0 RO 1 ADC1 DC0 Present When set, indicates that ADC module 1 Digital Comparator 0 is present. 15:8 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 7 ADC0DC7 RO 1 ADC0 DC7 Present When set, indicates that ADC module 0 Digital Comparator 7 is present. July 03, 2014 257 Texas Instruments-Production Data System Control Bit/Field Name Type Reset 6 ADC0DC6 RO 1 Description ADC0 DC6 Present When set, indicates that ADC module 0 Digital Comparator 6 is present. 5 ADC0DC5 RO 1 ADC0 DC5 Present When set, indicates that ADC module 0 Digital Comparator 5 is present. 4 ADC0DC4 RO 1 ADC0 DC4 Present When set, indicates that ADC module 0 Digital Comparator 4 is present. 3 ADC0DC3 RO 1 ADC0 DC3 Present When set, indicates that ADC module 0 Digital Comparator 3 is present. 2 ADC0DC2 RO 1 ADC0 DC2 Present When set, indicates that ADC module 0 Digital Comparator 2 is present. 1 ADC0DC1 RO 1 ADC0 DC1 Present When set, indicates that ADC module 0 Digital Comparator 1 is present. 0 ADC0DC0 RO 1 ADC0 DC0 Present When set, indicates that ADC module 0 Digital Comparator 0 is present. 258 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 27: Non-Volatile Memory Information (NVMSTAT), offset 0x1A0 This register is predefined by the part and can be used to verify features. Non-Volatile Memory Information (NVMSTAT) Base 0x400F.E000 Offset 0x1A0 Type RO, reset 0x0000.0001 31 30 29 28 27 26 25 24 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 8 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 7 6 5 4 3 2 1 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 reserved Type Reset reserved Type Reset RO 0 FWB RO 1 Bit/Field Name Type Reset Description 31:1 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 0 FWB RO 1 32 Word Flash Write Buffer Active When set, indicates that the 32 word Flash memory write buffer feature is active. July 03, 2014 259 Texas Instruments-Production Data System Control Register 28: Run Mode Clock Gating Control Register 0 (RCGC0), offset 0x100 This register controls the clock gating logic in normal Run mode. Each bit controls a clock enable for a given interface, function, or module. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled (saving power). If the module is unclocked, reads or writes to the module generate a bus fault. The reset state of these bits is 0 (unclocked) unless otherwise noted, so that all functional modules are disabled. It is the responsibility of software to enable the ports necessary for the application. Note that these registers may contain more bits than there are interfaces, functions, or modules to control. This configuration is implemented to assure reasonable code compatibility with other family and future parts. RCGC0 is the clock configuration register for running operation, SCGC0 for Sleep operation, and DCGC0 for Deep-Sleep operation. Setting the ACG bit in the Run-Mode Clock Configuration (RCC) register specifies that the system uses sleep modes. Run Mode Clock Gating Control Register 0 (RCGC0) Base 0x400F.E000 Offset 0x100 Type R/W, reset 0x00000040 31 30 29 reserved Type Reset 28 WDT1 26 24 23 22 21 20 19 18 16 CAN1 CAN0 ADC1 ADC0 RO 0 R/W 0 RO 0 RO 0 R/W 0 R/W 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 R/W 0 R/W 0 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 RO 0 RO 0 RO 0 MAXADC1SPD MAXADC0SPD R/W 0 R/W 0 R/W 0 R/W 0 reserved 17 RO 0 RO 0 reserved 25 RO 0 reserved Type Reset 27 reserved HIB RO 0 R/W 1 reserved RO 0 RO 0 WDT0 R/W 0 reserved RO 0 RO 0 RO 0 Bit/Field Name Type Reset Description 31:29 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 28 WDT1 R/W 0 WDT1 Clock Gating Control This bit controls the clock gating for the Watchdog Timer module 1. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 27:26 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 25 CAN1 R/W 0 CAN1 Clock Gating Control This bit controls the clock gating for CAN module 1. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 24 CAN0 R/W 0 CAN0 Clock Gating Control This bit controls the clock gating for CAN module 0. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 260 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Bit/Field Name Type Reset Description 23:18 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 17 ADC1 R/W 0 ADC1 Clock Gating Control This bit controls the clock gating for SAR ADC module 1. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 16 ADC0 R/W 0 ADC0 Clock Gating Control This bit controls the clock gating for ADC module 0. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 15:12 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 11:10 MAXADC1SPD R/W 0 ADC1 Sample Speed This field sets the rate at which ADC module 1 samples data. You cannot set the rate higher than the maximum rate. You can set the sample rate by setting the MAXADC1SPD bit as follows (all other encodings are reserved): Value Description 9:8 MAXADC0SPD R/W 0 0x3 1M samples/second 0x2 500K samples/second 0x1 250K samples/second 0x0 125K samples/second ADC0 Sample Speed This field sets the rate at which ADC0 samples data. You cannot set the rate higher than the maximum rate. You can set the sample rate by setting the MAXADC0SPD bit as follows (all other encodings are reserved): Value Description 0x3 1M samples/second 0x2 500K samples/second 0x1 250K samples/second 0x0 125K samples/second 7 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 6 HIB R/W 1 HIB Clock Gating Control This bit controls the clock gating for the Hibernation module. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. July 03, 2014 261 Texas Instruments-Production Data System Control Bit/Field Name Type Reset Description 5:4 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 3 WDT0 R/W 0 WDT0 Clock Gating Control This bit controls the clock gating for the Watchdog Timer module 0. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 2:0 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 262 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 29: Sleep Mode Clock Gating Control Register 0 (SCGC0), offset 0x110 This register controls the clock gating logic in Sleep mode. Each bit controls a clock enable for a given interface, function, or module. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled (saving power). If the module is unclocked, reads or writes to the module generate a bus fault. The reset state of these bits is 0 (unclocked) unless otherwise noted, so that all functional modules are disabled. It is the responsibility of software to enable the ports necessary for the application. Note that these registers may contain more bits than there are interfaces, functions, or modules to control. This configuration is implemented to assure reasonable code compatibility with other family and future parts. RCGC0 is the clock configuration register for running operation, SCGC0 for Sleep operation, and DCGC0 for Deep-Sleep operation. Setting the ACG bit in the Run-Mode Clock Configuration (RCC) register specifies that the system uses sleep modes. Sleep Mode Clock Gating Control Register 0 (SCGC0) Base 0x400F.E000 Offset 0x110 Type R/W, reset 0x00000040 31 30 29 reserved Type Reset 28 WDT1 RO 0 RO 0 RO 0 R/W 0 15 14 13 12 reserved Type Reset RO 0 RO 0 RO 0 RO 0 27 26 reserved RO 0 RO 0 11 10 25 24 CAN1 CAN0 R/W 0 R/W 0 9 8 MAXADC1SPD MAXADC0SPD R/W 0 R/W 0 R/W 0 R/W 0 23 22 21 20 19 18 reserved RO 0 RO 0 RO 0 RO 0 5 4 7 6 reserved HIB RO 0 R/W 1 reserved RO 0 RO 0 RO 0 RO 0 3 2 WDT0 R/W 0 17 16 ADC1 ADC0 R/W 0 R/W 0 1 0 reserved RO 0 RO 0 RO 0 Bit/Field Name Type Reset Description 31:29 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 28 WDT1 R/W 0 WDT1 Clock Gating Control This bit controls the clock gating for Watchdog Timer module 1. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 27:26 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 25 CAN1 R/W 0 CAN1 Clock Gating Control This bit controls the clock gating for CAN module 1. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 24 CAN0 R/W 0 CAN0 Clock Gating Control This bit controls the clock gating for CAN module 0. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. July 03, 2014 263 Texas Instruments-Production Data System Control Bit/Field Name Type Reset Description 23:18 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 17 ADC1 R/W 0 ADC1 Clock Gating Control This bit controls the clock gating for ADC module 1. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 16 ADC0 R/W 0 ADC0 Clock Gating Control This bit controls the clock gating for ADC module 0. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 15:12 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 11:10 MAXADC1SPD R/W 0 ADC1 Sample Speed This field sets the rate at which ADC module 1 samples data. You cannot set the rate higher than the maximum rate. You can set the sample rate by setting the MAXADC1SPD bit as follows (all other encodings are reserved): Value Description 9:8 MAXADC0SPD R/W 0 0x3 1M samples/second 0x2 500K samples/second 0x1 250K samples/second 0x0 125K samples/second ADC0 Sample Speed This field sets the rate at which ADC module 0 samples data. You cannot set the rate higher than the maximum rate. You can set the sample rate by setting the MAXADC0SPD bit as follows (all other encodings are reserved): Value Description 0x3 1M samples/second 0x2 500K samples/second 0x1 250K samples/second 0x0 125K samples/second 7 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 6 HIB R/W 1 HIB Clock Gating Control This bit controls the clock gating for the Hibernation module. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 264 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Bit/Field Name Type Reset Description 5:4 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 3 WDT0 R/W 0 WDT0 Clock Gating Control This bit controls the clock gating for the Watchdog Timer module 0. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 2:0 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. July 03, 2014 265 Texas Instruments-Production Data System Control Register 30: Deep Sleep Mode Clock Gating Control Register 0 (DCGC0), offset 0x120 This register controls the clock gating logic in Deep-Sleep mode. Each bit controls a clock enable for a given interface, function, or module. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled (saving power). If the module is unclocked, reads or writes to the module generate a bus fault. The reset state of these bits is 0 (unclocked) unless otherwise noted, so that all functional modules are disabled. It is the responsibility of software to enable the ports necessary for the application. Note that these registers may contain more bits than there are interfaces, functions, or modules to control. This configuration is implemented to assure reasonable code compatibility with other family and future parts. RCGC0 is the clock configuration register for running operation, SCGC0 for Sleep operation, and DCGC0 for Deep-Sleep operation. Setting the ACG bit in the Run-Mode Clock Configuration (RCC) register specifies that the system uses sleep modes. Deep Sleep Mode Clock Gating Control Register 0 (DCGC0) Base 0x400F.E000 Offset 0x120 Type R/W, reset 0x00000040 31 30 29 reserved Type Reset 28 WDT1 RO 0 RO 0 RO 0 R/W 0 15 14 13 12 27 26 reserved 25 24 CAN1 CAN0 23 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 R/W 0 R/W 0 RO 0 11 10 9 8 7 RO 0 RO 0 RO 0 20 RO 0 RO 0 RO 0 6 5 4 HIB RO 0 21 19 18 reserved reserved Type Reset 22 RO 0 R/W 1 reserved RO 0 RO 0 RO 0 RO 0 3 2 WDT0 R/W 0 17 16 ADC1 ADC0 R/W 0 R/W 0 1 0 reserved RO 0 RO 0 RO 0 Bit/Field Name Type Reset Description 31:29 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 28 WDT1 R/W 0 WDT1 Clock Gating Control This bit controls the clock gating for the Watchdog Timer module 1. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 27:26 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 25 CAN1 R/W 0 CAN1 Clock Gating Control This bit controls the clock gating for CAN module 1. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 24 CAN0 R/W 0 CAN0 Clock Gating Control This bit controls the clock gating for CAN module 0. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 266 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Bit/Field Name Type Reset Description 23:18 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 17 ADC1 R/W 0 ADC1 Clock Gating Control This bit controls the clock gating for ADC module 1. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 16 ADC0 R/W 0 ADC0 Clock Gating Control This bit controls the clock gating for ADC module 0. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 15:7 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 6 HIB R/W 1 HIB Clock Gating Control This bit controls the clock gating for the Hibernation module. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 5:4 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 3 WDT0 R/W 0 WDT0 Clock Gating Control This bit controls the clock gating for the Watchdog Timer module 0. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 2:0 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. July 03, 2014 267 Texas Instruments-Production Data System Control Register 31: Run Mode Clock Gating Control Register 1 (RCGC1), offset 0x104 This register controls the clock gating logic in normal Run mode. Each bit controls a clock enable for a given interface, function, or module. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled (saving power). If the module is unclocked, reads or writes to the module generate a bus fault. The reset state of these bits is 0 (unclocked) unless otherwise noted, so that all functional modules are disabled. It is the responsibility of software to enable the ports necessary for the application. Note that these registers may contain more bits than there are interfaces, functions, or modules to control. This configuration is implemented to assure reasonable code compatibility with other family and future parts. RCGC1 is the clock configuration register for running operation, SCGC1 for Sleep operation, and DCGC1 for Deep-Sleep operation. Setting the ACG bit in the Run-Mode Clock Configuration (RCC) register specifies that the system uses sleep modes. Run Mode Clock Gating Control Register 1 (RCGC1) Base 0x400F.E000 Offset 0x104 Type R/W, reset 0x00000000 Type Reset Type Reset 31 30 29 28 27 26 25 24 23 22 reserved EPI0 reserved I2S0 reserved COMP2 COMP1 COMP0 RO 0 R/W 0 RO 0 R/W 0 RO 0 R/W 0 R/W 0 15 14 13 12 11 10 9 reserved I2C1 reserved I2C0 RO 0 R/W 0 RO 0 R/W 0 RO 0 RO 0 RO 0 21 20 19 18 17 16 R/W 0 RO 0 RO 0 RO 0 RO 0 TIMER3 TIMER2 TIMER1 TIMER0 R/W 0 R/W 0 R/W 0 R/W 0 8 7 6 5 4 3 2 1 0 RO 0 RO 0 RO 0 SSI1 SSI0 reserved UART2 UART1 UART0 R/W 0 R/W 0 RO 0 R/W 0 R/W 0 R/W 0 reserved reserved Bit/Field Name Type Reset Description 31 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 30 EPI0 R/W 0 EPI0 Clock Gating This bit controls the clock gating for EPI module 0. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 29 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 28 I2S0 R/W 0 I2S0 Clock Gating This bit controls the clock gating for I2S module 0. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 27 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 268 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Bit/Field Name Type Reset 26 COMP2 R/W 0 Description Analog Comparator 2 Clock Gating This bit controls the clock gating for analog comparator 2. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 25 COMP1 R/W 0 Analog Comparator 1 Clock Gating This bit controls the clock gating for analog comparator 1. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 24 COMP0 R/W 0 Analog Comparator 0 Clock Gating This bit controls the clock gating for analog comparator 0. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 23:20 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 19 TIMER3 R/W 0 Timer 3 Clock Gating Control This bit controls the clock gating for General-Purpose Timer module 3. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 18 TIMER2 R/W 0 Timer 2 Clock Gating Control This bit controls the clock gating for General-Purpose Timer module 2. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 17 TIMER1 R/W 0 Timer 1 Clock Gating Control This bit controls the clock gating for General-Purpose Timer module 1. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 16 TIMER0 R/W 0 Timer 0 Clock Gating Control This bit controls the clock gating for General-Purpose Timer module 0. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 15 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 14 I2C1 R/W 0 I2C1 Clock Gating Control This bit controls the clock gating for I2C module 1. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. July 03, 2014 269 Texas Instruments-Production Data System Control Bit/Field Name Type Reset Description 13 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 12 I2C0 R/W 0 I2C0 Clock Gating Control This bit controls the clock gating for I2C module 0. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 11:6 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 5 SSI1 R/W 0 SSI1 Clock Gating Control This bit controls the clock gating for SSI module 1. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 4 SSI0 R/W 0 SSI0 Clock Gating Control This bit controls the clock gating for SSI module 0. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 3 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 2 UART2 R/W 0 UART2 Clock Gating Control This bit controls the clock gating for UART module 2. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 1 UART1 R/W 0 UART1 Clock Gating Control This bit controls the clock gating for UART module 1. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 0 UART0 R/W 0 UART0 Clock Gating Control This bit controls the clock gating for UART module 0. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 270 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 32: Sleep Mode Clock Gating Control Register 1 (SCGC1), offset 0x114 This register controls the clock gating logic in Sleep mode. Each bit controls a clock enable for a given interface, function, or module. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled (saving power). If the module is unclocked, reads or writes to the module generate a bus fault. The reset state of these bits is 0 (unclocked) unless otherwise noted, so that all functional modules are disabled. It is the responsibility of software to enable the ports necessary for the application. Note that these registers may contain more bits than there are interfaces, functions, or modules to control. This configuration is implemented to assure reasonable code compatibility with other family and future parts. RCGC1 is the clock configuration register for running operation, SCGC1 for Sleep operation, and DCGC1 for Deep-Sleep operation. Setting the ACG bit in the Run-Mode Clock Configuration (RCC) register specifies that the system uses sleep modes. Sleep Mode Clock Gating Control Register 1 (SCGC1) Base 0x400F.E000 Offset 0x114 Type R/W, reset 0x00000000 Type Reset Type Reset 31 30 29 28 27 26 25 24 reserved EPI0 reserved I2S0 reserved COMP2 COMP1 COMP0 RO 0 R/W 0 RO 0 R/W 0 RO 0 R/W 0 R/W 0 R/W 0 RO 0 RO 0 11 10 9 8 7 6 15 14 13 12 reserved I2C1 reserved I2C0 RO 0 R/W 0 RO 0 R/W 0 23 22 reserved RO 0 RO 0 RO 0 RO 0 21 20 reserved RO 0 RO 0 RO 0 RO 0 19 18 17 16 TIMER3 TIMER2 TIMER1 TIMER0 R/W 0 R/W 0 R/W 0 R/W 0 5 4 3 2 1 0 SSI1 SSI0 reserved UART2 UART1 UART0 R/W 0 R/W 0 RO 0 R/W 0 R/W 0 R/W 0 Bit/Field Name Type Reset Description 31 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 30 EPI0 R/W 0 EPI0 Clock Gating This bit controls the clock gating for EPI module 0. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 29 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 28 I2S0 R/W 0 I2S0 Clock Gating This bit controls the clock gating for I2S module 0. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 27 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. July 03, 2014 271 Texas Instruments-Production Data System Control Bit/Field Name Type Reset 26 COMP2 R/W 0 Description Analog Comparator 2 Clock Gating This bit controls the clock gating for analog comparator 2. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 25 COMP1 R/W 0 Analog Comparator 1 Clock Gating This bit controls the clock gating for analog comparator 1. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 24 COMP0 R/W 0 Analog Comparator 0 Clock Gating This bit controls the clock gating for analog comparator 0. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 23:20 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 19 TIMER3 R/W 0 Timer 3 Clock Gating Control This bit controls the clock gating for General-Purpose Timer module 3. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 18 TIMER2 R/W 0 Timer 2 Clock Gating Control This bit controls the clock gating for General-Purpose Timer module 2. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 17 TIMER1 R/W 0 Timer 1 Clock Gating Control This bit controls the clock gating for General-Purpose Timer module 1. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 16 TIMER0 R/W 0 Timer 0 Clock Gating Control This bit controls the clock gating for General-Purpose Timer module 0. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 15 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 14 I2C1 R/W 0 I2C1 Clock Gating Control This bit controls the clock gating for I2C module 1. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 272 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Bit/Field Name Type Reset Description 13 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 12 I2C0 R/W 0 I2C0 Clock Gating Control This bit controls the clock gating for I2C module 0. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 11:6 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 5 SSI1 R/W 0 SSI1 Clock Gating Control This bit controls the clock gating for SSI module 1. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 4 SSI0 R/W 0 SSI0 Clock Gating Control This bit controls the clock gating for SSI module 0. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 3 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 2 UART2 R/W 0 UART2 Clock Gating Control This bit controls the clock gating for UART module 2. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 1 UART1 R/W 0 UART1 Clock Gating Control This bit controls the clock gating for UART module 1. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 0 UART0 R/W 0 UART0 Clock Gating Control This bit controls the clock gating for UART module 0. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. July 03, 2014 273 Texas Instruments-Production Data System Control Register 33: Deep-Sleep Mode Clock Gating Control Register 1 (DCGC1), offset 0x124 This register controls the clock gating logic in Deep-Sleep mode. Each bit controls a clock enable for a given interface, function, or module. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled (saving power). If the module is unclocked, reads or writes to the module generate a bus fault. The reset state of these bits is 0 (unclocked) unless otherwise noted, so that all functional modules are disabled. It is the responsibility of software to enable the ports necessary for the application. Note that these registers may contain more bits than there are interfaces, functions, or modules to control. This configuration is implemented to assure reasonable code compatibility with other family and future parts. RCGC1 is the clock configuration register for running operation, SCGC1 for Sleep operation, and DCGC1 for Deep-Sleep operation. Setting the ACG bit in the Run-Mode Clock Configuration (RCC) register specifies that the system uses sleep modes. Deep-Sleep Mode Clock Gating Control Register 1 (DCGC1) Base 0x400F.E000 Offset 0x124 Type R/W, reset 0x00000000 Type Reset Type Reset 31 30 29 28 27 26 25 24 reserved EPI0 reserved I2S0 reserved COMP2 COMP1 COMP0 RO 0 R/W 0 RO 0 R/W 0 RO 0 R/W 0 R/W 0 R/W 0 RO 0 RO 0 11 10 9 8 7 6 15 14 13 12 reserved I2C1 reserved I2C0 RO 0 R/W 0 RO 0 R/W 0 23 22 reserved RO 0 RO 0 RO 0 RO 0 21 20 reserved RO 0 RO 0 RO 0 RO 0 19 18 17 16 TIMER3 TIMER2 TIMER1 TIMER0 R/W 0 R/W 0 R/W 0 R/W 0 5 4 3 2 1 0 SSI1 SSI0 reserved UART2 UART1 UART0 R/W 0 R/W 0 RO 0 R/W 0 R/W 0 R/W 0 Bit/Field Name Type Reset Description 31 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 30 EPI0 R/W 0 EPI0 Clock Gating This bit controls the clock gating for EPI module 0. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 29 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 28 I2S0 R/W 0 I2S0 Clock Gating This bit controls the clock gating for I2S module 0. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 27 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 274 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Bit/Field Name Type Reset 26 COMP2 R/W 0 Description Analog Comparator 2 Clock Gating This bit controls the clock gating for analog comparator 2. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 25 COMP1 R/W 0 Analog Comparator 1 Clock Gating This bit controls the clock gating for analog comparator 1. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 24 COMP0 R/W 0 Analog Comparator 0 Clock Gating This bit controls the clock gating for analog comparator 0. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 23:20 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 19 TIMER3 R/W 0 Timer 3 Clock Gating Control This bit controls the clock gating for General-Purpose Timer module 3. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 18 TIMER2 R/W 0 Timer 2 Clock Gating Control This bit controls the clock gating for General-Purpose Timer module 2. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 17 TIMER1 R/W 0 Timer 1 Clock Gating Control This bit controls the clock gating for General-Purpose Timer module 1. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 16 TIMER0 R/W 0 Timer 0 Clock Gating Control This bit controls the clock gating for General-Purpose Timer module 0. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 15 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 14 I2C1 R/W 0 I2C1 Clock Gating Control This bit controls the clock gating for I2C module 1. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. July 03, 2014 275 Texas Instruments-Production Data System Control Bit/Field Name Type Reset Description 13 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 12 I2C0 R/W 0 I2C0 Clock Gating Control This bit controls the clock gating for I2C module 0. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 11:6 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 5 SSI1 R/W 0 SSI1 Clock Gating Control This bit controls the clock gating for SSI module 1. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 4 SSI0 R/W 0 SSI0 Clock Gating Control This bit controls the clock gating for SSI module 0. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 3 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 2 UART2 R/W 0 UART2 Clock Gating Control This bit controls the clock gating for UART module 2. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 1 UART1 R/W 0 UART1 Clock Gating Control This bit controls the clock gating for UART module 1. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 0 UART0 R/W 0 UART0 Clock Gating Control This bit controls the clock gating for UART module 0. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 276 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 34: Run Mode Clock Gating Control Register 2 (RCGC2), offset 0x108 This register controls the clock gating logic in normal Run mode. Each bit controls a clock enable for a given interface, function, or module. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled (saving power). If the module is unclocked, reads or writes to the module generate a bus fault. The reset state of these bits is 0 (unclocked) unless otherwise noted, so that all functional modules are disabled. It is the responsibility of software to enable the ports necessary for the application. Note that these registers may contain more bits than there are interfaces, functions, or modules to control. This configuration is implemented to assure reasonable code compatibility with other family and future parts. RCGC2 is the clock configuration register for running operation, SCGC2 for Sleep operation, and DCGC2 for Deep-Sleep operation. Setting the ACG bit in the Run-Mode Clock Configuration (RCC) register specifies that the system uses sleep modes. Run Mode Clock Gating Control Register 2 (RCGC2) Base 0x400F.E000 Offset 0x108 Type R/W, reset 0x00000000 Type Reset 31 30 29 28 reserved EPHY0 reserved EMAC0 RO 0 R/W 0 RO 0 15 14 13 reserved Type Reset RO 0 RO 0 27 26 25 24 23 R/W 0 RO 0 RO 0 RO 0 RO 0 RO 0 12 11 10 9 8 RO 0 RO 0 UDMA R/W 0 22 21 20 19 18 17 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 R/W 0 7 6 5 4 3 2 1 0 GPIOJ GPIOH GPIOG GPIOF GPIOE GPIOD GPIOC GPIOB GPIOA R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 reserved reserved RO 0 RO 0 16 USB0 Bit/Field Name Type Reset Description 31 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 30 EPHY0 R/W 0 PHY0 Clock Gating Control This bit controls the clock gating for Ethernet PHY layer 0. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 29 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 28 EMAC0 R/W 0 MAC0 Clock Gating Control This bit controls the clock gating for Ethernet MAC layer 0. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 27:17 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. July 03, 2014 277 Texas Instruments-Production Data System Control Bit/Field Name Type Reset 16 USB0 R/W 0 Description USB0 Clock Gating Control This bit controls the clock gating for USB module 0. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 15:14 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 13 UDMA R/W 0 Micro-DMA Clock Gating Control This bit controls the clock gating for micro-DMA. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 12:9 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 8 GPIOJ R/W 0 Port J Clock Gating Control This bit controls the clock gating for Port J. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 7 GPIOH R/W 0 Port H Clock Gating Control This bit controls the clock gating for Port H. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 6 GPIOG R/W 0 Port G Clock Gating Control This bit controls the clock gating for Port G. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 5 GPIOF R/W 0 Port F Clock Gating Control This bit controls the clock gating for Port F. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 4 GPIOE R/W 0 Port E Clock Gating Control Port E Clock Gating Control. This bit controls the clock gating for Port E. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 3 GPIOD R/W 0 Port D Clock Gating Control Port D Clock Gating Control. This bit controls the clock gating for Port D. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 278 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Bit/Field Name Type Reset 2 GPIOC R/W 0 Description Port C Clock Gating Control This bit controls the clock gating for Port C. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 1 GPIOB R/W 0 Port B Clock Gating Control This bit controls the clock gating for Port B. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 0 GPIOA R/W 0 Port A Clock Gating Control This bit controls the clock gating for Port A. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. July 03, 2014 279 Texas Instruments-Production Data System Control Register 35: Sleep Mode Clock Gating Control Register 2 (SCGC2), offset 0x118 This register controls the clock gating logic in Sleep mode. Each bit controls a clock enable for a given interface, function, or module. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled (saving power). If the module is unclocked, reads or writes to the module generate a bus fault. The reset state of these bits is 0 (unclocked) unless otherwise noted, so that all functional modules are disabled. It is the responsibility of software to enable the ports necessary for the application. Note that these registers may contain more bits than there are interfaces, functions, or modules to control. This configuration is implemented to assure reasonable code compatibility with other family and future parts. RCGC2 is the clock configuration register for running operation, SCGC2 for Sleep operation, and DCGC2 for Deep-Sleep operation. Setting the ACG bit in the Run-Mode Clock Configuration (RCC) register specifies that the system uses sleep modes. Sleep Mode Clock Gating Control Register 2 (SCGC2) Base 0x400F.E000 Offset 0x118 Type R/W, reset 0x00000000 Type Reset 31 30 29 28 reserved EPHY0 reserved EMAC0 RO 0 R/W 0 RO 0 R/W 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 reserved Type Reset RO 0 RO 0 UDMA R/W 0 27 26 25 23 22 21 20 19 18 17 reserved reserved RO 0 24 RO 0 RO 0 RO 0 RO 0 RO 0 16 USB0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 R/W 0 8 7 6 5 4 3 2 1 0 GPIOJ GPIOH GPIOG GPIOF GPIOE GPIOD GPIOC GPIOB GPIOA R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 Bit/Field Name Type Reset Description 31 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 30 EPHY0 R/W 0 PHY0 Clock Gating Control This bit controls the clock gating for Ethernet PHY layer 0. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 29 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 28 EMAC0 R/W 0 MAC0 Clock Gating Control This bit controls the clock gating for Ethernet MAC layer 0. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 27:17 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 280 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Bit/Field Name Type Reset 16 USB0 R/W 0 Description USB0 Clock Gating Control This bit controls the clock gating for USB module 0. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 15:14 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 13 UDMA R/W 0 Micro-DMA Clock Gating Control This bit controls the clock gating for micro-DMA. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 12:9 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 8 GPIOJ R/W 0 Port J Clock Gating Control This bit controls the clock gating for Port J. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 7 GPIOH R/W 0 Port H Clock Gating Control This bit controls the clock gating for Port H. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 6 GPIOG R/W 0 Port G Clock Gating Control This bit controls the clock gating for Port G. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 5 GPIOF R/W 0 Port F Clock Gating Control This bit controls the clock gating for Port F. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 4 GPIOE R/W 0 Port E Clock Gating Control Port E Clock Gating Control. This bit controls the clock gating for Port E. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 3 GPIOD R/W 0 Port D Clock Gating Control Port D Clock Gating Control. This bit controls the clock gating for Port D. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. July 03, 2014 281 Texas Instruments-Production Data System Control Bit/Field Name Type Reset 2 GPIOC R/W 0 Description Port C Clock Gating Control This bit controls the clock gating for Port C. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 1 GPIOB R/W 0 Port B Clock Gating Control This bit controls the clock gating for Port B. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 0 GPIOA R/W 0 Port A Clock Gating Control This bit controls the clock gating for Port A. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 282 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 36: Deep Sleep Mode Clock Gating Control Register 2 (DCGC2), offset 0x128 This register controls the clock gating logic in Deep-Sleep mode. Each bit controls a clock enable for a given interface, function, or module. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled (saving power). If the module is unclocked, reads or writes to the module generate a bus fault. The reset state of these bits is 0 (unclocked) unless otherwise noted, so that all functional modules are disabled. It is the responsibility of software to enable the ports necessary for the application. Note that these registers may contain more bits than there are interfaces, functions, or modules to control. This configuration is implemented to assure reasonable code compatibility with other family and future parts. RCGC2 is the clock configuration register for running operation, SCGC2 for Sleep operation, and DCGC2 for Deep-Sleep operation. Setting the ACG bit in the Run-Mode Clock Configuration (RCC) register specifies that the system uses sleep modes. Deep Sleep Mode Clock Gating Control Register 2 (DCGC2) Base 0x400F.E000 Offset 0x128 Type R/W, reset 0x00000000 Type Reset 31 30 29 28 reserved EPHY0 reserved EMAC0 RO 0 R/W 0 RO 0 R/W 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 reserved Type Reset RO 0 RO 0 UDMA R/W 0 27 26 25 23 22 21 20 19 18 17 reserved reserved RO 0 24 RO 0 RO 0 RO 0 RO 0 RO 0 16 USB0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 R/W 0 8 7 6 5 4 3 2 1 0 GPIOJ GPIOH GPIOG GPIOF GPIOE GPIOD GPIOC GPIOB GPIOA R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 Bit/Field Name Type Reset Description 31 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 30 EPHY0 R/W 0 PHY0 Clock Gating Control This bit controls the clock gating for Ethernet PHY layer 0. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 29 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 28 EMAC0 R/W 0 MAC0 Clock Gating Control This bit controls the clock gating for Ethernet MAC layer 0. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 27:17 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. July 03, 2014 283 Texas Instruments-Production Data System Control Bit/Field Name Type Reset 16 USB0 R/W 0 Description USB0 Clock Gating Control This bit controls the clock gating for USB module 0. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 15:14 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 13 UDMA R/W 0 Micro-DMA Clock Gating Control This bit controls the clock gating for micro-DMA. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 12:9 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 8 GPIOJ R/W 0 Port J Clock Gating Control This bit controls the clock gating for Port J. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 7 GPIOH R/W 0 Port H Clock Gating Control This bit controls the clock gating for Port H. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 6 GPIOG R/W 0 Port G Clock Gating Control This bit controls the clock gating for Port G. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 5 GPIOF R/W 0 Port F Clock Gating Control This bit controls the clock gating for Port F. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 4 GPIOE R/W 0 Port E Clock Gating Control Port E Clock Gating Control. This bit controls the clock gating for Port E. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 3 GPIOD R/W 0 Port D Clock Gating Control Port D Clock Gating Control. This bit controls the clock gating for Port D. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 284 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Bit/Field Name Type Reset 2 GPIOC R/W 0 Description Port C Clock Gating Control This bit controls the clock gating for Port C. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 1 GPIOB R/W 0 Port B Clock Gating Control This bit controls the clock gating for Port B. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. 0 GPIOA R/W 0 Port A Clock Gating Control This bit controls the clock gating for Port A. If set, the module receives a clock and functions. Otherwise, the module is unclocked and disabled. If the module is unclocked, a read or write to the module generates a bus fault. July 03, 2014 285 Texas Instruments-Production Data System Control Register 37: Software Reset Control 0 (SRCR0), offset 0x040 This register allows individual modules to be reset. Writes to this register are masked by the bits in the Device Capabilities 1 (DC1) register. Software Reset Control 0 (SRCR0) Base 0x400F.E000 Offset 0x040 Type R/W, reset 0x00000000 31 30 29 reserved Type Reset 28 WDT1 27 26 reserved 25 24 23 22 21 19 18 reserved 17 16 CAN1 CAN0 ADC1 ADC0 RO 0 RO 0 RO 0 R/W 0 RO 0 RO 0 R/W 0 R/W 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 R/W 0 R/W 0 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 R/W 0 reserved Type Reset 20 HIB RO 0 reserved RO 0 RO 0 WDT0 R/W 0 reserved RO 0 RO 0 RO 0 Bit/Field Name Type Reset Description 31:29 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 28 WDT1 R/W 0 WDT1 Reset Control When this bit is set, Watchdog Timer module 1 is reset. All internal data is lost and the registers are returned to their reset states. This bit must be manually cleared after being set. 27:26 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 25 CAN1 R/W 0 CAN1 Reset Control When this bit is set, CAN module 1 is reset. All internal data is lost and the registers are returned to their reset states. This bit must be manually cleared after being set. 24 CAN0 R/W 0 CAN0 Reset Control When this bit is set, CAN module 0 is reset. All internal data is lost and the registers are returned to their reset states. This bit must be manually cleared after being set. 23:18 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 17 ADC1 R/W 0 ADC1 Reset Control When this bit is set, ADC module 1 is reset. All internal data is lost and the registers are returned to their reset states. This bit must be manually cleared after being set. 16 ADC0 R/W 0 ADC0 Reset Control When this bit is set, ADC module 0 is reset. All internal data is lost and the registers are returned to their reset states. This bit must be manually cleared after being set. 286 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Bit/Field Name Type Reset Description 15:7 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 6 HIB R/W 0 HIB Reset Control When this bit is set, the Hibernation module is reset. All internal data is lost and the registers are returned to their reset states.This bit must be manually cleared after being set. 5:4 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 3 WDT0 R/W 0 WDT0 Reset Control When this bit is set, Watchdog Timer module 0 is reset. All internal data is lost and the registers are returned to their reset states. This bit must be manually cleared after being set. 2:0 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. July 03, 2014 287 Texas Instruments-Production Data System Control Register 38: Software Reset Control 1 (SRCR1), offset 0x044 This register allows individual modules to be reset. Writes to this register are masked by the bits in the Device Capabilities 2 (DC2) register. Software Reset Control 1 (SRCR1) Base 0x400F.E000 Offset 0x044 Type R/W, reset 0x00000000 Type Reset Type Reset 31 30 29 28 27 26 25 24 23 22 reserved EPI0 reserved I2S0 reserved COMP2 COMP1 COMP0 RO 0 R/W 0 RO 0 R/W 0 RO 0 R/W 0 R/W 0 15 14 13 12 11 10 9 reserved I2C1 reserved I2C0 RO 0 R/W 0 RO 0 R/W 0 RO 0 RO 0 RO 0 21 20 19 18 17 16 R/W 0 RO 0 RO 0 RO 0 RO 0 TIMER3 TIMER2 TIMER1 TIMER0 R/W 0 R/W 0 R/W 0 R/W 0 8 7 6 5 4 3 2 1 0 RO 0 RO 0 RO 0 SSI1 SSI0 reserved UART2 UART1 UART0 R/W 0 R/W 0 RO 0 R/W 0 R/W 0 R/W 0 reserved reserved Bit/Field Name Type Reset Description 31 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 30 EPI0 R/W 0 EPI0 Reset Control When this bit is set, EPI module 0 is reset. All internal data is lost and the registers are returned to their reset states. This bit must be manually cleared after being set. 29 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 28 I2S0 R/W 0 I2S0 Reset Control When this bit is set, I2S module 0 is reset. All internal data is lost and the registers are returned to their reset states. This bit must be manually cleared after being set. 27 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 26 COMP2 R/W 0 Analog Comp 2 Reset Control When this bit is set, Analog Comparator module 2 is reset. All internal data is lost and the registers are returned to their reset states. This bit must be manually cleared after being set. 25 COMP1 R/W 0 Analog Comp 1 Reset Control When this bit is set, Analog Comparator module 1 is reset. All internal data is lost and the registers are returned to their reset states. This bit must be manually cleared after being set. 24 COMP0 R/W 0 Analog Comp 0 Reset Control When this bit is set, Analog Comparator module 0 is reset. All internal data is lost and the registers are returned to their reset states. This bit must be manually cleared after being set. 288 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Bit/Field Name Type Reset Description 23:20 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 19 TIMER3 R/W 0 Timer 3 Reset Control Timer 3 Reset Control. When this bit is set, General-Purpose Timer module 3 is reset. All internal data is lost and the registers are returned to their reset states. This bit must be manually cleared after being set. 18 TIMER2 R/W 0 Timer 2 Reset Control When this bit is set, General-Purpose Timer module 2 is reset. All internal data is lost and the registers are returned to their reset states. This bit must be manually cleared after being set. 17 TIMER1 R/W 0 Timer 1 Reset Control When this bit is set, General-Purpose Timer module 1 is reset. All internal data is lost and the registers are returned to their reset states. This bit must be manually cleared after being set. 16 TIMER0 R/W 0 Timer 0 Reset Control When this bit is set, General-Purpose Timer module 0 is reset. All internal data is lost and the registers are returned to their reset states. This bit must be manually cleared after being set. 15 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 14 I2C1 R/W 0 I2C1 Reset Control When this bit is set, I2C module 1 is reset. All internal data is lost and the registers are returned to their reset states. This bit must be manually cleared after being set. 13 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 12 I2C0 R/W 0 I2C0 Reset Control When this bit is set, I2C module 0 is reset. All internal data is lost and the registers are returned to their reset states. This bit must be manually cleared after being set. 11:6 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 5 SSI1 R/W 0 SSI1 Reset Control When this bit is set, SSI module 1 is reset. All internal data is lost and the registers are returned to their reset states. This bit must be manually cleared after being set. 4 SSI0 R/W 0 SSI0 Reset Control When this bit is set, SSI module 0 is reset. All internal data is lost and the registers are returned to their reset states. This bit must be manually cleared after being set. July 03, 2014 289 Texas Instruments-Production Data System Control Bit/Field Name Type Reset Description 3 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 2 UART2 R/W 0 UART2 Reset Control When this bit is set, UART module 2 is reset. All internal data is lost and the registers are returned to their reset states. This bit must be manually cleared after being set. 1 UART1 R/W 0 UART1 Reset Control When this bit is set, UART module 1 is reset. All internal data is lost and the registers are returned to their reset states. This bit must be manually cleared after being set. 0 UART0 R/W 0 UART0 Reset Control When this bit is set, UART module 0 is reset. All internal data is lost and the registers are returned to their reset states. This bit must be manually cleared after being set. 290 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 39: Software Reset Control 2 (SRCR2), offset 0x048 This register allows individual modules to be reset. Writes to this register are masked by the bits in the Device Capabilities 4 (DC4) register. Software Reset Control 2 (SRCR2) Base 0x400F.E000 Offset 0x048 Type R/W, reset 0x00000000 Type Reset 31 30 29 28 reserved EPHY0 reserved EMAC0 RO 0 R/W 0 RO 0 15 14 13 reserved Type Reset RO 0 RO 0 27 26 25 24 23 R/W 0 RO 0 RO 0 RO 0 RO 0 RO 0 12 11 10 9 8 RO 0 RO 0 UDMA R/W 0 22 21 20 19 18 17 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 R/W 0 7 6 5 4 3 2 1 0 GPIOJ GPIOH GPIOG GPIOF GPIOE GPIOD GPIOC GPIOB GPIOA R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 reserved reserved RO 0 RO 0 16 USB0 Bit/Field Name Type Reset Description 31 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 30 EPHY0 R/W 0 PHY0 Reset Control When this bit is set, Ethernet PHY layer 0 is reset. All internal data is lost and the registers are returned to their reset states. This bit must be manually cleared after being set. 29 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 28 EMAC0 R/W 0 MAC0 Reset Control When this bit is set, Ethernet MAC layer 0 is reset. All internal data is lost and the registers are returned to their reset states. This bit must be manually cleared after being set. 27:17 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 16 USB0 R/W 0 USB0 Reset Control When this bit is set, USB module 0 is reset. All internal data is lost and the registers are returned to their reset states. This bit must be manually cleared after being set. 15:14 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 13 UDMA R/W 0 Micro-DMA Reset Control When this bit is set, uDMA module is reset. All internal data is lost and the registers are returned to their reset states. This bit must be manually cleared after being set. July 03, 2014 291 Texas Instruments-Production Data System Control Bit/Field Name Type Reset Description 12:9 reserved RO 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 8 GPIOJ R/W 0 Port J Reset Control When this bit is set, Port J module is reset. All internal data is lost and the registers are returned to their reset states. This bit must be manually cleared after being set. 7 GPIOH R/W 0 Port H Reset Control When this bit is set, Port H module is reset. All internal data is lost and the registers are returned to their reset states. This bit must be manually cleared after being set. 6 GPIOG R/W 0 Port G Reset Control When this bit is set, Port G module is reset. All internal data is lost and the registers are returned to their reset states. This bit must be manually cleared after being set. 5 GPIOF R/W 0 Port F Reset Control When this bit is set, Port F module is reset. All internal data is lost and the registers are returned to their reset states. This bit must be manually cleared after being set. 4 GPIOE R/W 0 Port E Reset Control When this bit is set, Port E module is reset. All internal data is lost and the registers are returned to their reset states. This bit must be manually cleared after being set. 3 GPIOD R/W 0 Port D Reset Control When this bit is set, Port D module is reset. All internal data is lost and the registers are returned to their reset states. This bit must be manually cleared after being set. 2 GPIOC R/W 0 Port C Reset Control When this bit is set, Port C module is reset. All internal data is lost and the registers are returned to their reset states. This bit must be manually cleared after being set. 1 GPIOB R/W 0 Port B Reset Control When this bit is set, Port B module is reset. All internal data is lost and the registers are returned to their reset states. This bit must be manually cleared after being set. 0 GPIOA R/W 0 Port A Reset Control When this bit is set, Port A module is reset. All internal data is lost and the registers are returned to their reset states. This bit must be manually cleared after being set. 292 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller 6 Hibernation Module The Hibernation Module manages removal and restoration of power to provide a means for reducing power consumption. When the processor and peripherals are idle, power can be completely removed with only the Hibernation module remaining powered. Power can be restored based on an external signal or at a certain time using the built-in Real-Time Clock (RTC). The Hibernation module can be independently supplied from a battery or an auxiliary power supply. The Hibernation module has the following features: ■ 32-bit real-time counter (RTC) – Two 32-bit RTC match registers for timed wake-up and interrupt generation – RTC predivider trim for making fine adjustments to the clock rate ■ Two mechanisms for power control – System power control using discrete external regulator – On-chip power control using internal switches under register control ■ Dedicated pin for waking using an external signal ■ RTC operational and hibernation memory valid as long as VBAT is valid ■ Low-battery detection, signaling, and interrupt generation ■ Clock source from a 32.768-kHz external oscillator or a 4.194304-MHz crystal; 32.768-kHz external oscillator can be used for main controller clock ■ 64 32-bit words of battery-backed memory to save state during hibernation ■ Programmable interrupts for RTC match, external wake, and low battery events July 03, 2014 293 Texas Instruments-Production Data Hibernation Module 6.1 Block Diagram Figure 6-1. Hibernation Module Block Diagram HIBCTL.CLK32EN XOSC0 Interrupts HIBIM HIBRIS HIBMIS HIBIC Pre-Divider XOSC1 HIBRTCT /128 HIBCTL.CLKSEL Battery-Backed Memory 64 words HIBDATA RTC HIBRTCC HIBRTCLD HIBRTCM0 HIBRTCM1 Clock Source for System Clock Interrupts to CPU MATCH0/1 HIBCTL.RTCEN WAKE LOWBAT Power Sequence Logic Low Battery Detect VBAT HIBCTL.LOWBATEN HIB HIBCTL.PWRCUT HIBCTL.RTCWEN HIBCTL.PINWEN HIBCTL.VABORT HIBCTL.HIBREQ 6.2 Signal Description The following table lists the external signals of the Hibernation module and describes the function of each. These signals have dedicated functions and are not alternate functions for any GPIO signals. Table 6-1. Hibernate Signals (100LQFP) Pin Name Pin Number Pin Mux / Pin Assignment a Pin Type Buffer Type Description HIB 51 fixed O OD An output that indicates the processor is in Hibernate mode. VBAT 55 fixed - Power Power source for the Hibernation module. It is normally connected to the positive terminal of a battery and serves as the battery backup/Hibernation module power-source supply. WAKE 50 fixed I TTL An external input that brings the processor out of Hibernate mode when asserted. XOSC0 52 fixed I Analog Hibernation module oscillator crystal input or an external clock reference input. Note that this is either a 4.194304-MHz crystal or a 32.768-kHz oscillator for the Hibernation module RTC. See the CLKSEL bit in the HIBCTL register. XOSC1 53 fixed O Analog Hibernation module oscillator crystal output. Leave unconnected when using a single-ended clock source. a. The TTL designation indicates the pin has TTL-compatible voltage levels. 294 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Table 6-2. Hibernate Signals (108BGA) Pin Name Pin Number Pin Mux / Pin Assignment a Pin Type Buffer Type Description HIB M12 fixed O OD An output that indicates the processor is in Hibernate mode. VBAT L12 fixed - Power Power source for the Hibernation module. It is normally connected to the positive terminal of a battery and serves as the battery backup/Hibernation module power-source supply. WAKE M10 fixed I TTL An external input that brings the processor out of Hibernate mode when asserted. XOSC0 K11 fixed I Analog Hibernation module oscillator crystal input or an external clock reference input. Note that this is either a 4.194304-MHz crystal or a 32.768-kHz oscillator for the Hibernation module RTC. See the CLKSEL bit in the HIBCTL register. XOSC1 K12 fixed O Analog Hibernation module oscillator crystal output. Leave unconnected when using a single-ended clock source. a. The TTL designation indicates the pin has TTL-compatible voltage levels. 6.3 Functional Description The Hibernation module provides two mechanisms for power control: ■ The first mechanism controls the power to the microcontroller with a control signal (HIB) that signals an external voltage regulator to turn on or off. ■ The second mechanism uses internal switches to control power to the Cortex-M3 as well as to most analog and digital functions while retaining I/O pin power (VDD3ON mode). The Hibernation module power source is determined dynamically. The supply voltage of the Hibernation module is the larger of the main voltage source (VDD) or the battery/auxilliary voltage source (VBAT). The Hibernation module also has an independent clock source to maintain a real-time clock (RTC) when the system clock is powered down. Once in hibernation, the module signals an external voltage regulator to turn the power back on when an external pin (WAKE) is asserted or when the internal RTC reaches a certain value. The Hibernation module can also detect when the battery voltage is low and optionally prevent hibernation when this occurs. When waking from hibernation, the HIB signal is deasserted. The return of VDD causes a POR to be executed. The time from when the WAKE signal is asserted to when code begins execution is equal to the wake-up time (tWAKE_TO_HIB) plus the power-on reset time (TIRPOR). 6.3.1 Register Access Timing Because the Hibernation module has an independent clocking domain, certain registers must be written only with a timing gap between accesses. The delay time is tHIB_REG_ACCESS, therefore software must guarantee that this delay is inserted between back-to-back writes to certain Hibernation registers or between a write followed by a read to those same registers. Software may make use of the WRC bit in the Hibernation Control (HIBCTL) register to ensure that the required timing gap has elapsed. This bit is cleared on a write operation and set once the write completes, indicating to software that another write or read may be started safely. Software should poll HIBCTL for WRC=1 prior to accessing any affected register. The following registers are subject to this timing restriction: July 03, 2014 295 Texas Instruments-Production Data Hibernation Module ■ Hibernation RTC Counter (HIBRTCC) ■ Hibernation RTC Match 0 (HIBRTCM0) ■ Hibernation RTC Match 1 (HIBRTCM1) ■ Hibernation RTC Load (HIBRTCLD) ■ Hibernation RTC Trim (HIBRTCT) ■ Hibernation Data (HIBDATA) Back-to-back reads from Hibernation module registers have no timing restrictions. Reads are performed at the full peripheral clock rate. 6.3.2 Hibernation Clock Source In systems where the Hibernation module is used to put the microcontroller into hibernation, the module must be clocked by an external source that is independent from the main system clock, even if the RTC feature is not used. An external oscillator or crystal is used for this purpose. To use a crystal, a 4.194304-MHz crystal is connected to the XOSC0 and XOSC1 pins. This clock signal is divided by 128 internally to produce a 32.768-kHz Hibernation clock reference. Alternatively, a 32.768-kHz oscillator can be connected to the XOSC0 pin, leaving XOSC1 unconnected. Care must be taken that the voltage amplitude of the 32.768-kHz oscillator is less than VBAT, otherwise, the Hibernation module may draw power from the oscillator and not VBAT during hibernation. See Figure 6-2 on page 297 and Figure 6-3 on page 297. The Hibernation clock source is enabled by setting the CLK32EN bit of the HIBCTL register. The type of clock source is selected by clearing the CLKSEL bit for a 4.194304-MHz crystal and setting the CLKSEL bit for a 32.768-kHz oscillator. If a crystal is used for the clock source, the software must leave a delay of tHIBOSC_START after writing to the CLK32EN bit and before any other accesses to the Hibernation module registers. The delay allows the crystal to power up and stabilize. If an oscillator is used for the clock source, no delay is needed. 296 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Figure 6-2. Using a Crystal as the Hibernation Clock Source Stellaris® Microcontroller Regulator or Switch Input Voltage IN OUT VDD EN XOSC0 X1 RL XOSC1 C1 C2 HIB WAKE RPU1 Open drain external wake up circuit Note: VBAT GND 3V Battery RPU2 X1 = Crystal frequency is fXOSC_XTAL. C1,2 = Capacitor value derived from crystal vendor load capacitance specifications. RL = Load resistor is RXOSC_LOAD. RPU1 = Pull-up resistor 1 (value and voltage source (VBAT or Input Voltage) determined by regulator or switch enable input characteristics). RPU2 = Pull-up resistor 2 is 200 kΩ See “Hibernation Clock Source Specifications” on page 1229 for specific parameter values. Figure 6-3. Using a Dedicated Oscillator as the Hibernation Clock Source with VDD3ON Mode Stellaris® Microcontroller Regulator Input Voltage IN OUT VDD Clock Source XOSC0 (fEXT_OSC) N.C. XOSC1 HIB WAKE Open drain external wake up circuit Note: 6.3.3 VBAT GND RPU 3V Battery RPU = Pull-up resistor is 1 MΩ System Implementation Several different system configurations are possible when using the Hibernation module: ■ Using a single battery source, where the battery provides both VDD and VBAT. July 03, 2014 297 Texas Instruments-Production Data Hibernation Module ■ Using the VDD3ON mode, where VDD continues to be powered in hibernation, allowing the GPIO pins to retain their states, as shown in Figure 6-3 on page 297. In this mode, VDDC is powered off internally. ■ Using separate sources for VDD and VBAT, as shown in Figure 6-2 on page 297. ■ Using a regulator to provide both VDD and VBAT with a switch enabled by HIB to remove VDD during hibernation. Adding external capacitance to the VBAT supply reduces the accuracy of the low-battery measurement and should be avoided if possible. The diagrams referenced in this section only show the connection to the Hibernation pins and not to the full system. If the application does not require the use of the Hibernation module, refer to “Connections for Unused Signals” on page 1218. In this situation, the HIB bit in the Run Mode Clock Gating Control Register 0 (RCGC0) register must be cleared, disabling the system clock to the Hibernation module and Hibernation module registers are not accessible. 6.3.4 Battery Management Important: System-level factors may affect the accuracy of the low battery detect circuit. The designer should consider battery type, discharge characteristics, and a test load during battery voltage measurements. The Hibernation module can be independently powered by a battery or an auxiliary power source using the VBAT pin. The module can monitor the voltage level of the battery and detect when the voltage drops below VLOWBAT. The module can also be configured so that it does not go into Hibernate mode if the battery voltage drops below this threshold. Battery voltage is not measured while in Hibernate mode. The Hibernation module can be configured to detect a low battery condition by setting the LOWBATEN bit of the HIBCTL register. In this configuration, the LOWBAT bit of the Hibernation Raw Interrupt Status (HIBRIS) register is set when the battery level is low. If the VABORT bit in the HIBCTL register is also set, then the module is prevented from entering Hibernate mode when a low battery is detected. The module can also be configured to generate an interrupt for the low-battery condition (see “Interrupts and Status” on page 300). Note that the Hibernation module draws power from whichever source (VBAT or VDD) has the higher voltage. Therefore, it is important to design the circuit to ensure that VDD is higher that VBAT under nominal conditions or else the Hibernation module draws power from the battery even when VDD is available. 6.3.5 Real-Time Clock The Hibernation module includes a 32-bit counter that increments once per second with the proper configuration (see “Hibernation Clock Source” on page 296). The 32.768-kHz clock signal, either directly from the 32.768-kHz oscillator or from the 4.194304-MHz crystal divided by 128, is fed into a predivider register that counts down the 32.768-kHz clock ticks to achieve a once per second clock rate for the RTC. The rate can be adjusted to compensate for inaccuracies in the clock source by using the predivider trim register, HIBRTCT. This register has a nominal value of 0x7FFF, and is used for one second out of every 64 seconds to divide the input clock. This configuration allows the software to make fine corrections to the clock rate by adjusting the predivider trim register up or down from 0x7FFF. The predivider trim should be adjusted up from 0x7FFF in order to slow down the RTC rate and down from 0x7FFF in order to speed up the RTC rate. 298 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller The Hibernation module includes two 32-bit match registers that are compared to the value of the RTC counter. The match registers can be used to wake the processor from Hibernate mode or to generate an interrupt to the processor if it is not in hibernation. The RTC must be enabled with the RTCEN bit of the HIBCTL register. The value of the RTC can be set at any time by writing to the HIBRTCLD register. The predivider trim can be adjusted by reading and writing the HIBRTCT register. The predivider uses this register once every 64 seconds to adjust the clock rate. The two match registers can be set by writing to the HIBRTCM0 and HIBRTCM1 registers. The RTC can be configured to generate interrupts by using the interrupt registers (see “Interrupts and Status” on page 300). As long as the RTC is enabled and a valid VBAT is present, the RTC continues counting, regardless of whether VDD is present or if the part is in hibernation. 6.3.6 Battery-Backed Memory The Hibernation module contains 64 32-bit words of memory that are powered from the battery or auxiliary power supply and therefore retained during hibernation. The processor software can save state information in this memory prior to hibernation and recover the state upon waking. The battery-backed memory can be accessed through the HIBDATA registers. If both VDD and VBAT are removed, the contents of the HIBDATA registers are not retained. 6.3.7 Power Control Using HIB Important: The Hibernation Module requires special system implementation considerations when using HIB to control power, as it is intended to power-down all other sections of the microcontroller. All system signals and power supplies that connect to the chip must be driven to 0 VDC or powered down with the same regulator controlled by HIB. The Hibernation module controls power to the microcontroller through the use of the HIB pin which is intended to be connected to the enable signal of the external regulator(s) providing 3.3 V to the microcontroller and other circuits. When the HIB signal is asserted by the Hibernation module, the external regulator is turned off and no longer powers the microcontroller and any parts of the system that are powered by the regulator. The Hibernation module remains powered from the VBAT supply (which could be a battery or an auxiliary power source) until a Wake event. Power to the microcontroller is restored by deasserting the HIB signal, which causes the external regulator to turn power back on to the chip. 6.3.8 Power Control Using VDD3ON Mode The Hibernation module may also be configured to cut power to all internal modules. While in this state, all pins are configured as inputs. In the VDD3ON mode, the regulator should maintain 3.3 V power to the microcontroller during Hibernate. This power control mode is enabled by setting the VDD3ON bit in HIBCTL. 6.3.9 Initiating Hibernate Hibernate mode is initiated when the HIBREQ bit of the HIBCTL register is set. If a wake-up condition has not been configured using the PINWEN or RTCWEN bits in the HIBCTL register, the hibernation request is ignored. If a Flash memory write operation is in progress when the HIBREQ bit is set, an interlock feature holds off the transition into Hibernate mode until the write has completed. 6.3.10 Waking from Hibernate The Hibernation module is configured to wake from the external WAKE pin by setting the PINWEN bit of the HIBCTL register. It is configured to wake from RTC match by setting the RTCWEN bit. Note that the WAKE pin uses the Hibernation module's internal power supply as the logic 1 reference. July 03, 2014 299 Texas Instruments-Production Data Hibernation Module Upon either external wake-up or RTC match, the Hibernation module delays coming out of hibernation until VDD is above the minimum specified voltage, see Table 25-2 on page 1222. When the Hibernation module wakes, the microcontroller performs a normal power-on reset. Note that this reset does not reset the Hibernation module, but does reset the rest of the microcontroller. Software can detect that the power-on was due to a wake from hibernation by examining the raw interrupt status register (see “Interrupts and Status” on page 300) and by looking for state data in the battery-backed memory (see “Battery-Backed Memory” on page 299). 6.3.11 Interrupts and Status The Hibernation module can generate interrupts when the following conditions occur: ■ Assertion of WAKE pin ■ RTC match ■ Low battery detected All of the interrupts are ORed together before being sent to the interrupt controller, so the Hibernate module can only generate a single interrupt request to the controller at any given time. The software interrupt handler can service multiple interrupt events by reading the Hibernation Masked Interrupt Status (HIBMIS) register. Software can also read the status of the Hibernation module at any time by reading the HIBRIS register which shows all of the pending events. This register can be used after waking from hibernation to see if the wake condition was caused by the WAKE signal or the RTC match. The events that can trigger an interrupt are configured by setting the appropriate bits in the Hibernation Interrupt Mask (HIBIM) register. Pending interrupts can be cleared by writing the corresponding bit in the Hibernation Interrupt Clear (HIBIC) register. 6.4 Initialization and Configuration The Hibernation module has several different configurations. The following sections show the recommended programming sequence for various scenarios. The examples below assume that a 32.768-kHz oscillator is used, and thus always set the CLKSEL bit of the HIBCTL register. If a 4.194304-MHz crystal is used instead, then the CLKSEL bit remains cleared. Because the Hibernation module runs at 32.768 kHz and is asynchronous to the rest of the microcontroller, which is run off the system clock, software must allow a delay of tHIB_REG_ACCESS after writes to certain registers (see “Register Access Timing” on page 295). The registers that require a delay are listed in a note in “Register Map” on page 302 as well as in each register description. 6.4.1 Initialization The Hibernation module comes out of reset with the system clock enabled to the module, but if the system clock to the module has been disabled, then it must be re-enabled, even if the RTC feature is not used. See page 260. If a 4.194304-MHz crystal is used as the Hibernation module clock source, perform the following step: 1. Write 0x40 to the HIBCTL register at offset 0x10 to enable the crystal and select the divide-by-128 input path. If a 32.678-kHz single-ended oscillator is used as the Hibernation module clock source, then perform the following steps: 300 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller 1. Write 0x44 to the HIBCTL register at offset 0x10 to enable the oscillator input and bypass the on-chip oscillator. 2. No delay is necessary. The above steps are only necessary when the entire system is initialized for the first time. If the microcontroller has been in hibernation, then the Hibernation module has already been powered up and the above steps are not necessary. The software can detect that the Hibernation module and clock are already powered by examining the CLK32EN bit of the HIBCTL register. Table 6-3 on page 301 illustrates how the clocks function with various bit setting both in normal operation and in hibernation. Table 6-3. Hibernation Module Clock Operation CLK32EN PINWEN RTCWEN CLKSEL RTCEN Result Normal Operation 6.4.2 Result Hibernation 0 X X X X Hibernation module disabled Hibernation module disabled 1 0 0 0 1 RTC match capability enabled. Module clocked from 4.184304-MHz crystal. No hibernation 1 0 0 1 1 RTC match capability enabled. Module clocked from 32.768-kHz oscillator. No hibernation 1 0 1 X 1 Module clocked from selected source RTC match for wake-up event 1 1 0 X 0 Module clocked from selected source Clock is powered down during hibernation and powered up again on external wake-up event. 1 1 0 X 1 Module clocked from selected source Clock is powered up during hibernation for RTC. Wake up on external event. 1 1 1 X 1 Module clocked from selected source RTC match or external wake-up event, whichever occurs first. RTC Match Functionality (No Hibernation) Use the following steps to implement the RTC match functionality of the Hibernation module: 1. Write the required RTC match value to one of the HIBRTCMn registers at offset 0x004 or 0x008. 2. Write the required RTC load value to the HIBRTCLD register at offset 0x00C. 3. Set the required RTC match interrupt mask in the RTCALT0 and RTCALT1 bits (bits 1:0) in the HIBIM register at offset 0x014. 4. Write 0x0000.0041 to the HIBCTL register at offset 0x010 to enable the RTC to begin counting. 6.4.3 RTC Match/Wake-Up from Hibernation Use the following steps to implement the RTC match and wake-up functionality of the Hibernation module: 1. Write the required RTC match value to the HIBRTCMn registers at offset 0x004 or 0x008. 2. Write the required RTC load value to the HIBRTCLD register at offset 0x00C. July 03, 2014 301 Texas Instruments-Production Data Hibernation Module 3. Write any data to be retained during power cut to the HIBDATA register at offsets 0x030-0x12C. 4. Set the RTC Match Wake-Up and start the hibernation sequence by writing 0x0000.004F to the HIBCTL register at offset 0x010. 6.4.4 External Wake-Up from Hibernation Use the following steps to implement the Hibernation module with the external WAKE pin as the wake-up source for the microcontroller: 1. Write any data to be retained during power cut to the HIBDATA register at offsets 0x030-0x12C. 2. Enable the external wake and start the hibernation sequence by writing 0x0000.0056 to the HIBCTL register at offset 0x010. Note that in this mode, if the RTC is disabled, then the Hibernation clock source is powered down during Hibernate mode and is powered up again on the external wake event to save power during hibernation. If the RTC is enabled before hibernation, it continues to operate during hibernation. 6.4.5 RTC or External Wake-Up from Hibernation 1. Write the required RTC match value to the HIBRTCMn registers at offset 0x004 or 0x008. 2. Write the required RTC load value to the HIBRTCLD register at offset 0x00C. 3. Write any data to be retained during power cut to the HIBDATA register at offsets 0x030-0x12C. 4. Set the RTC Match/External Wake-Up and start the hibernation sequence by writing 0x0000.005F to the HIBCTL register at offset 0x010. 6.5 Register Map Table 6-4 on page 303 lists the Hibernation registers. All addresses given are relative to the Hibernation Module base address at 0x400F.C000. Note that the system clock to the Hibernation module must be enabled before the registers can be programmed (see page 260). There must be a delay of 3 system clocks after the Hibernation module clock is enabled before any Hibernation module registers are accessed. Note: HIBRTCC, HIBRTCM0, HIBRTCM1, HIBRTCLD, HIBRTCT, and HIBDATA are on the Hibernation module clock domain and have special timing requirements. Software should make use of the WRC bit in the HIBCTL register to ensure that the required timing gap has elapsed. If the WRC bit is clear, any attempted write access is ignored. See “Register Access Timing” on page 295. Important: The Hibernation module registers are reset under two conditions: 1. A system reset when the RTCEN and the PINWEN bits in the HIBCTL register are both cleared. 2. A cold POR, when both the VDD and VBAT supplies are removed. Any other reset condition is ignored by the Hibernation module. 302 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Table 6-4. Hibernation Module Register Map Offset Name 0x000 Reset HIBRTCC RO 0x0000.0000 Hibernation RTC Counter 304 0x004 HIBRTCM0 R/W 0xFFFF.FFFF Hibernation RTC Match 0 305 0x008 HIBRTCM1 R/W 0xFFFF.FFFF Hibernation RTC Match 1 306 0x00C HIBRTCLD R/W 0xFFFF.FFFF Hibernation RTC Load 307 0x010 HIBCTL R/W 0x8000.0000 Hibernation Control 308 0x014 HIBIM R/W 0x0000.0000 Hibernation Interrupt Mask 311 0x018 HIBRIS RO 0x0000.0000 Hibernation Raw Interrupt Status 313 0x01C HIBMIS RO 0x0000.0000 Hibernation Masked Interrupt Status 315 0x020 HIBIC R/W1C 0x0000.0000 Hibernation Interrupt Clear 317 0x024 HIBRTCT R/W 0x0000.7FFF Hibernation RTC Trim 318 0x0300x12C HIBDATA R/W - Hibernation Data 319 6.6 Description See page Type Register Descriptions The remainder of this section lists and describes the Hibernation module registers, in numerical order by address offset. July 03, 2014 303 Texas Instruments-Production Data Hibernation Module Register 1: Hibernation RTC Counter (HIBRTCC), offset 0x000 This register is the current 32-bit value of the RTC counter. Note: HIBRTCC, HIBRTCM0, HIBRTCM1, HIBRTCLD, HIBRTCT, and HIBDATA are on the Hibernation module clock domain and have special timing requirements. Software should make use of the WRC bit in the HIBCTL register to ensure that the required timing gap has elapsed. If the WRC bit is clear, any attempted write access is ignored. See “Register Access Timing” on page 295. Hibernation RTC Counter (HIBRTCC) Base 0x400F.C000 Offset 0x000 Type RO, reset 0x0000.0000 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 7 6 5 4 3 2 1 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RTCC Type Reset RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 8 RTCC Type Reset RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 Bit/Field Name Type 31:0 RTCC RO RO 0 Reset RO 0 Description 0x0000.0000 RTC Counter A read returns the 32-bit counter value, which represents the seconds elapsed since the RTC was enabled. This register is read-only. To change the value, use the HIBRTCLD register. 304 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 2: Hibernation RTC Match 0 (HIBRTCM0), offset 0x004 This register is the 32-bit match 0 register for the RTC counter. Note: HIBRTCC, HIBRTCM0, HIBRTCM1, HIBRTCLD, HIBRTCT, and HIBDATA are on the Hibernation module clock domain and have special timing requirements. Software should make use of the WRC bit in the HIBCTL register to ensure that the required timing gap has elapsed. If the WRC bit is clear, any attempted write access is ignored. See “Register Access Timing” on page 295. Hibernation RTC Match 0 (HIBRTCM0) Base 0x400F.C000 Offset 0x004 Type R/W, reset 0xFFFF.FFFF 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 RTCM0 Type Reset R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 RTCM0 Type Reset R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 Bit/Field Name Type 31:0 RTCM0 R/W R/W 1 Reset R/W 1 Description 0xFFFF.FFFF RTC Match 0 A write loads the value into the RTC match register. A read returns the current match value. July 03, 2014 305 Texas Instruments-Production Data Hibernation Module Register 3: Hibernation RTC Match 1 (HIBRTCM1), offset 0x008 This register is the 32-bit match 1 register for the RTC counter. Note: HIBRTCC, HIBRTCM0, HIBRTCM1, HIBRTCLD, HIBRTCT, and HIBDATA are on the Hibernation module clock domain and have special timing requirements. Software should make use of the WRC bit in the HIBCTL register to ensure that the required timing gap has elapsed. If the WRC bit is clear, any attempted write access is ignored. See “Register Access Timing” on page 295. Hibernation RTC Match 1 (HIBRTCM1) Base 0x400F.C000 Offset 0x008 Type R/W, reset 0xFFFF.FFFF 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 RTCM1 Type Reset R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 RTCM1 Type Reset R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 Bit/Field Name Type 31:0 RTCM1 R/W R/W 1 Reset R/W 1 Description 0xFFFF.FFFF RTC Match 1 A write loads the value into the RTC match register. A read returns the current match value. 306 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 4: Hibernation RTC Load (HIBRTCLD), offset 0x00C This register is used to load a 32-bit value loaded into the RTC counter. The load occurs immediately upon this register being written. Note: HIBRTCC, HIBRTCM0, HIBRTCM1, HIBRTCLD, HIBRTCT, and HIBDATA are on the Hibernation module clock domain and have special timing requirements. Software should make use of the WRC bit in the HIBCTL register to ensure that the required timing gap has elapsed. If the WRC bit is clear, any attempted write access is ignored. See “Register Access Timing” on page 295. Hibernation RTC Load (HIBRTCLD) Base 0x400F.C000 Offset 0x00C Type R/W, reset 0xFFFF.FFFF 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 RTCLD Type Reset R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 RTCLD Type Reset R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 Bit/Field Name Type 31:0 RTCLD R/W R/W 1 Reset R/W 1 Description 0xFFFF.FFFF RTC Load A write loads the current value into the RTC counter (RTCC). A read returns the 32-bit load value. July 03, 2014 307 Texas Instruments-Production Data Hibernation Module Register 5: Hibernation Control (HIBCTL), offset 0x010 This register is the control register for the Hibernation module. This register must be written last before a hibernate event is issued. Writes to other registers after the HIBREQ bit is set are not guaranteed to complete before hibernation is entered. Hibernation Control (HIBCTL) Base 0x400F.C000 Offset 0x010 Type R/W, reset 0x8000.0000 31 30 29 28 27 26 25 24 RO 1 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 8 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 WRC Type Reset 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 7 6 5 4 3 2 1 0 HIBREQ RTCEN R/W 0 R/W 0 reserved reserved Type Reset 23 RO 0 VDD3ON VABORT CLK32EN LOWBATEN PINWEN RTCWEN CLKSEL Bit/Field Name Type Reset 31 WRC RO 1 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 Description Write Complete/Capable Value Description 0 The interface is processing a prior write and is busy. Any write operation that is attempted while WRC is 0 results in undetermined behavior. 1 The interface is ready to accept a write. Software must poll this bit between write requests and defer writes until WRC=1 to ensure proper operation. The bit name WRC means "Write Complete," which is the normal use of the bit (between write accesses). However, because the bit is set out-of-reset, the name can also mean "Write Capable" which simply indicates that the interface may be written to by software. This difference may be exploited by software at reset time to detect which method of programming is appropriate: 0 = software delay loops required; 1 = WRC paced available. 30:9 reserved RO 0x000 8 VDD3ON R/W 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. VDD Powered Value Description 1 The internal switches control the power to the on-chip modules (VDD3ON mode). 0 The internal switches are not used. The HIB signal should be used to control an external switch or regulator. Note that regardless of the status of the VDD3ON bit, the HIB signal is asserted during Hibernate mode. Thus, when VDD3ON is set, the HIB signal should not be connected to the 3.3V regulator, and the 3.3V power source should remain connected. 308 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Bit/Field Name Type Reset 7 VABORT R/W 0 6 CLK32EN R/W 0 Description Power Cut Abort Enable Value Description 1 When this bit is set, the battery voltage level is checked before entering hibernation. If VBAT is less than VLOWBAT, the microcontroller does not go into hibernation. 0 The microcontroller goes into hibernation regardless of the voltage level of the battery. Clocking Enable This bit must be enabled to use the Hibernation module. 5 4 3 2 LOWBATEN PINWEN RTCWEN CLKSEL R/W R/W R/W R/W 0 0 0 0 Value Description 1 The Hibernation module clock source is enabled. 0 The Hibernation module clock source is disabled. Low Battery Monitoring Enable Value Description 1 Low battery voltage detection is enabled. When this bit is set, the battery voltage level is checked before entering hibernation. If VBAT is less than VLOWBAT, the LOWBAT bit in the HIBRIS register is set. 0 Low battery monitoring is disabled. External WAKE Pin Enable Value Description 1 An assertion of the WAKE pin takes the microcontroller out of hibernation. 0 The status of the WAKE pin has no effect on hibernation. RTC Wake-up Enable Value Description 1 An RTC match event (the value the HIBRTCC register matches the value of the HIBRTCM0 or HIBRTCM1 register) takes the microcontroller out of hibernation. 0 An RTC match event has no effect on hibernation. Hibernation Module Clock Select Value Description 1 Use raw output. Use this value for a 32.768-kHz oscillator. 0 Use Divide-by-128 output. Use this value for a 4.194304-MHz crystal. July 03, 2014 309 Texas Instruments-Production Data Hibernation Module Bit/Field Name Type Reset 1 HIBREQ R/W 0 Description Hibernation Request Value Description 1 Set this bit to initiate hibernation. 0 No hibernation request. After a wake-up event, this bit is automatically cleared by hardware. A hibernation request is ignored if both the PINWEN and RTCWEN bits are clear. 0 RTCEN R/W 0 RTC Timer Enable Value Description 1 The Hibernation module RTC is enabled. 0 The Hibernation module RTC is disabled. 310 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 6: Hibernation Interrupt Mask (HIBIM), offset 0x014 This register is the interrupt mask register for the Hibernation module interrupt sources. Each bit in this register masks the corresponding bit in the Hibernation Raw Interrupt Status (HIBRIS) register. If a bit is unmasked, the interrupt is sent to the interrupt controller. If the bit is masked, the interrupt is not sent to the interrupt controller. Hibernation Interrupt Mask (HIBIM) Base 0x400F.C000 Offset 0x014 Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 8 7 6 5 4 3 2 1 0 RO 0 RO 0 RO 0 RO 0 RO 0 reserved Type Reset reserved Type Reset EXTW Bit/Field Name Type Reset 31:4 reserved RO 0x0000.000 3 EXTW R/W 0 R/W 0 LOWBAT RTCALT1 RTCALT0 R/W 0 R/W 0 R/W 0 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. External Wake-Up Interrupt Mask Value Description 2 LOWBAT R/W 0 1 An interrupt is sent to the interrupt controller when the EXTW bit in the HIBRIS register is set. 0 The EXTW interrupt is suppressed and not sent to the interrupt controller. Low Battery Voltage Interrupt Mask Value Description 1 RTCALT1 R/W 0 1 An interrupt is sent to the interrupt controller when the LOWBAT bit in the HIBRIS register is set. 0 The LOWBAT interrupt is suppressed and not sent to the interrupt controller. RTC Alert 1 Interrupt Mask Value Description 1 An interrupt is sent to the interrupt controller when the RTCALT1 bit in the HIBRIS register is set. 0 The RTCALT1 interrupt is suppressed and not sent to the interrupt controller. July 03, 2014 311 Texas Instruments-Production Data Hibernation Module Bit/Field Name Type Reset 0 RTCALT0 R/W 0 Description RTC Alert 0 Interrupt Mask Value Description 1 An interrupt is sent to the interrupt controller when the RTCALT0 bit in the HIBRIS register is set. 0 The RTCALT0 interrupt is suppressed and not sent to the interrupt controller. 312 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 7: Hibernation Raw Interrupt Status (HIBRIS), offset 0x018 This register is the raw interrupt status for the Hibernation module interrupt sources. Each bit can be masked by clearing the corresponding bit in the HIBIM register. When a bit is masked, the interrupt is not sent to the interrupt controller. Bits in this register are cleared by writing a 1 to the corresponding bit in the Hibernation Interrupt Clear (HIBIC) register or by entering hibernation. Hibernation Raw Interrupt Status (HIBRIS) Base 0x400F.C000 Offset 0x018 Type RO, reset 0x0000.0000 31 30 29 28 27 26 25 24 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 8 7 6 5 4 3 2 1 0 RO 0 RO 0 RO 0 RO 0 RO 0 reserved Type Reset reserved Type Reset EXTW Bit/Field Name Type Reset 31:4 reserved RO 0x0000.000 3 EXTW RO 0 RO 0 LOWBAT RTCALT1 RTCALT0 RO 0 RO 0 RO 0 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. External Wake-Up Raw Interrupt Status Value Description 1 The WAKE pin has been asserted. 0 The WAKE pin has not been asserted. This bit is cleared by writing a 1 to the EXTW bit in the HIBIC register. 2 LOWBAT RO 0 Low Battery Voltage Raw Interrupt Status Value Description 1 The battery voltage dropped below VLOWBAT. 0 The battery voltage has not dropped below VLOWBAT. This bit is cleared by writing a 1 to the LOWBAT bit in the HIBIC register. 1 RTCALT1 RO 0 RTC Alert 1 Raw Interrupt Status Value Description 1 The value of the HIBRTCC register matches the value in the HIBRTCM1 register. 0 No match This bit is cleared by writing a 1 to the RTCALT1 bit in the HIBIC register. July 03, 2014 313 Texas Instruments-Production Data Hibernation Module Bit/Field Name Type Reset 0 RTCALT0 RO 0 Description RTC Alert 0 Raw Interrupt Status Value Description 1 The value of the HIBRTCC register matches the value in the HIBRTCM0 register. 0 No match This bit is cleared by writing a 1 to the RTCALT0 bit in the HIBIC register. 314 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 8: Hibernation Masked Interrupt Status (HIBMIS), offset 0x01C This register is the masked interrupt status for the Hibernation module interrupt sources. Bits in this register are the AND of the corresponding bits in the HIBRIS and HIBIM registers. When both corresponding bits are set, the bit in this register is set, and the interrupt is sent to the interrupt controller. Hibernation Masked Interrupt Status (HIBMIS) Base 0x400F.C000 Offset 0x01C Type RO, reset 0x0000.0000 31 30 29 28 27 26 25 24 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 8 7 6 5 4 3 2 1 0 RO 0 RO 0 RO 0 RO 0 RO 0 reserved Type Reset reserved Type Reset EXTW Bit/Field Name Type Reset 31:4 reserved RO 0x0000.000 3 EXTW RO 0 RO 0 LOWBAT RTCALT1 RTCALT0 RO 0 RO 0 RO 0 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. External Wake-Up Masked Interrupt Status Value Description 1 An unmasked interrupt was signaled due to a WAKE pin assertion. 0 An external wake-up interrupt has not occurred or is masked. This bit is cleared by writing a 1 to the EXTW bit in the HIBIC register. 2 LOWBAT RO 0 Low Battery Voltage Masked Interrupt Status Value Description 1 An unmasked interrupt was signaled due to a low battery voltage condition. 0 A low battery voltage interrupt has not occurred or is masked. This bit is cleared by writing a 1 to the LOWBAT bit in the HIBIC register. 1 RTCALT1 RO 0 RTC Alert 1 Masked Interrupt Status Value Description 1 An unmasked interrupt was signaled due to an RTC match. 0 An RTC match interrupt has not occurred or is masked. This bit is cleared by writing a 1 to the RTCALT1 bit in the HIBIC register. July 03, 2014 315 Texas Instruments-Production Data Hibernation Module Bit/Field Name Type Reset 0 RTCALT0 RO 0 Description RTC Alert 0 Masked Interrupt Status Value Description 1 An unmasked interrupt was signaled due to an RTC match. 0 An RTC match interrupt has not occurred or is masked. This bit is cleared by writing a 1 to the RTCALT0 bit in the HIBIC register. 316 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 9: Hibernation Interrupt Clear (HIBIC), offset 0x020 This register is the interrupt write-one-to-clear register for the Hibernation module interrupt sources. Writing a 1 to a bit clears the corresponding interrupt in the HIBRIS register. Hibernation Interrupt Clear (HIBIC) Base 0x400F.C000 Offset 0x020 Type R/W1C, reset 0x0000.0000 31 30 29 28 27 26 25 24 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 8 7 6 5 4 3 2 1 0 RO 0 RO 0 RO 0 RO 0 RO 0 R/W1C 0 reserved Type Reset reserved Type Reset EXTW Bit/Field Name Type Reset 31:4 reserved RO 0x0000.000 3 EXTW R/W1C 0 LOWBAT RTCALT1 RTCALT0 R/W1C 0 R/W1C 0 R/W1C 0 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. External Wake-Up Masked Interrupt Clear Writing a 1 to this bit clears the EXTW bit in the HIBRIS and HIBMIS registers. Reads return an indeterminate value. 2 LOWBAT R/W1C 0 Low Battery Voltage Masked Interrupt Clear Writing a 1 to this bit clears the LOWBAT bit in the HIBRIS and HIBMIS registers. Reads return an indeterminate value. 1 RTCALT1 R/W1C 0 RTC Alert1 Masked Interrupt Clear Writing a 1 to this bit clears the RTCALT1 bit in the HIBRIS and HIBMIS registers. Reads return an indeterminate value. 0 RTCALT0 R/W1C 0 RTC Alert0 Masked Interrupt Clear Writing a 1 to this bit clears the RTCALT0 bit in the HIBRIS and HIBMIS registers. Reads return an indeterminate value. July 03, 2014 317 Texas Instruments-Production Data Hibernation Module Register 10: Hibernation RTC Trim (HIBRTCT), offset 0x024 This register contains the value that is used to trim the RTC clock predivider. It represents the computed underflow value that is used during the trim cycle. It is represented as 0x7FFF ± N clock cycles, where N is the number of clock cycles to add or subtract every 63 seconds. Note: HIBRTCC, HIBRTCM0, HIBRTCM1, HIBRTCLD, HIBRTCT, and HIBDATA are on the Hibernation module clock domain and have special timing requirements. Software should make use of the WRC bit in the HIBCTL register to ensure that the required timing gap has elapsed. If the WRC bit is clear, any attempted write access is ignored. See “Register Access Timing” on page 295. Hibernation RTC Trim (HIBRTCT) Base 0x400F.C000 Offset 0x024 Type R/W, reset 0x0000.7FFF 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 7 6 5 4 3 2 1 0 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 reserved Type Reset RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 8 TRIM Type Reset R/W 0 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 Bit/Field Name Type Reset Description 31:16 reserved RO 0x0000 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 15:0 TRIM R/W 0x7FFF RTC Trim Value This value is loaded into the RTC predivider every 64 seconds. It is used to adjust the RTC rate to account for drift and inaccuracy in the clock source. Compensation can be adjusted by software by moving the default value of 0x7FFF up or down. Moving the value up slows down the RTC and moving the value down speeds up the RTC. 318 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 11: Hibernation Data (HIBDATA), offset 0x030-0x12C This address space is implemented as a 64x32-bit memory (256 bytes). It can be loaded by the system processor in order to store state information and does not lose power during a power cut operation as long as a battery is present. Note: HIBRTCC, HIBRTCM0, HIBRTCM1, HIBRTCLD, HIBRTCT, and HIBDATA are on the Hibernation module clock domain and have special timing requirements. Software should make use of the WRC bit in the HIBCTL register to ensure that the required timing gap has elapsed. If the WRC bit is clear, any attempted write access is ignored. See “Register Access Timing” on page 295. Hibernation Data (HIBDATA) Base 0x400F.C000 Offset 0x030-0x12C Type R/W, reset 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - 7 6 5 4 3 2 1 0 R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - RTD Type Reset R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - 15 14 13 12 11 10 9 8 RTD Type Reset R/W - R/W - R/W - R/W - R/W - R/W - R/W - Bit/Field Name Type Reset 31:0 RTD R/W - R/W - Description Hibernation Module NV Data July 03, 2014 319 Texas Instruments-Production Data Internal Memory 7 Internal Memory The LM3S9U90 microcontroller comes with 96 KB of bit-banded SRAM, internal ROM,and 384 KB of Flash memory. The Flash memory controller provides a user-friendly interface, making Flash memory programming a simple task. Flash memory protection can be applied to the Flash memory on a 2-KB block basis. 7.1 Block Diagram Figure 7-1 on page 320 illustrates the internal memory blocks and control logic. The dashed boxes in the figure indicate registers residing in the System Control module. Figure 7-1. Internal Memory Block Diagram ROM Control ROM Array RMCTL Flash Control Icode Bus Cortex-M3 FMA FMD FMC FCRIS FCIM FCMISC Dcode Bus Flash Array System Bus Flash Write Buffer FMC2 FWBVAL FWBn 32 words Flash Protection Bridge FMPREn FMPRE FMPPEn FMPPE User Registers Flash Timing BOOTCFG USECRL USER_REG0 USER_REG1 USER_REG2 USER_REG3 SRAM Array 7.2 Functional Description This section describes the functionality of the SRAM, ROM, and Flash memories. Note: The μDMA controller can transfer data to and from the on-chip SRAM. However, because the Flash memory and ROM are located on a separate internal bus, it is not possible to transfer data from the Flash memory or ROM with the μDMA controller. 320 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller 7.2.1 SRAM ® The internal SRAM of the Stellaris devices is located at address 0x2000.0000 of the device memory map. To reduce the number of time consuming read-modify-write (RMW) operations, ARM provides bit-banding technology in the processor. With a bit-band-enabled processor, certain regions in the memory map (SRAM and peripheral space) can use address aliases to access individual bits in a single, atomic operation. The bit-band base is located at address 0x2200.0000. The bit-band alias is calculated by using the formula: bit-band alias = bit-band base + (byte offset * 32) + (bit number * 4) For example, if bit 3 at address 0x2000.1000 is to be modified, the bit-band alias is calculated as: 0x2200.0000 + (0x1000 * 32) + (3 * 4) = 0x2202.000C With the alias address calculated, an instruction performing a read/write to address 0x2202.000C allows direct access to only bit 3 of the byte at address 0x2000.1000. For details about bit-banding, see “Bit-Banding” on page 92. Note: 7.2.2 The SRAM is implemented using two 32-bit wide SRAM banks (separate SRAM arrays). The banks are partitioned such that one bank contains all even words (the even bank) and the other contains all odd words (the odd bank). A write access that is followed immediately by a read access to the same bank incurs a stall of a single clock cycle. However, a write to one bank followed by a read of the other bank can occur in successive clock cycles without incurring any delay. ROM The internal ROM of the Stellaris device is located at address 0x0100.0000 of the device memory map. Detailed information on the ROM contents can be found in the Stellaris® ROM User’s Guide. The ROM contains the following components: ■ Stellaris Boot Loader and vector table ■ Stellaris Peripheral Driver Library (DriverLib) release for product-specific peripherals and interfaces ■ Advanced Encryption Standard (AES) cryptography tables ■ Cyclic Redundancy Check (CRC) error detection functionality The boot loader is used as an initial program loader (when the Flash memory is empty) as well as an application-initiated firmware upgrade mechanism (by calling back to the boot loader). The Peripheral Driver Library APIs in ROM can be called by applications, reducing Flash memory requirements and freeing the Flash memory to be used for other purposes (such as additional features in the application). Advance Encryption Standard (AES) is a publicly defined encryption standard used by the U.S. Government and Cyclic Redundancy Check (CRC) is a technique to validate a span of data has the same contents as when previously checked. 7.2.2.1 Boot Loader Overview The Stellaris Boot Loader is used to download code to the Flash memory of a device without the use of a debug interface. When the core is reset, the user has the opportunity to direct the core to execute the ROM Boot Loader or the application in Flash memory by using any GPIO signal in Ports A-H as configured in the Boot Configuration (BOOTCFG) register. July 03, 2014 321 Texas Instruments-Production Data Internal Memory At reset, the ROM is mapped over the Flash memory so that the ROM boot sequence is always executed. The boot sequence executed from ROM is as follows: 1. The BA bit (below) is cleared such that ROM is mapped to 0x01xx.xxxx and Flash memory is mapped to address 0x0. 2. The BOOTCFG register is read. If the EN bit is clear, the status of the specified GPIO pin is compared with the specified polarity. If the status matches the specified polarity, the ROM is mapped to address 0x0000.0000 and execution continues out of the ROM Boot Loader. 3. If the status doesn't match the specified polarity, the data at address 0x0000.0004 is read, and if the data at this address is 0xFFFF.FFFF, the ROM is mapped to address 0x0000.0000 and execution continues out of the ROM Boot Loader. 4. If there is data at address 0x0000.0004 that is not 0xFFFF.FFFF, the stack pointer (SP) is loaded from Flash memory at address 0x0000.0000 and the program counter (PC) is loaded from address 0x0000.0004. The user application begins executing. The boot loader uses a simple packet interface to provide synchronous communication with the device. The speed of the boot loader is determined by the internal oscillator (PIOSC) frequency as it does not enable the PLL. The following serial interfaces can be used: ■ UART0 ■ SSI0 ■ I2C0 ■ Ethernet For simplicity, both the data format and communication protocol are identical for all serial interfaces. Note: The Flash-memory-resident version of the Boot Loader also supports CAN and USB. See the Stellaris® Boot Loader User's Guide for information on the boot loader software. 7.2.2.2 Stellaris Peripheral Driver Library The Stellaris Peripheral Driver Library contains a file called driverlib/rom.h that assists with calling the peripheral driver library functions in the ROM. The detailed description of each function is available in the Stellaris® ROM User’s Guide. See the "Using the ROM" chapter of the Stellaris® Peripheral Driver Library User's Guide for more details on calling the ROM functions and using driverlib/rom.h. A table at the beginning of the ROM points to the entry points for the APIs that are provided in the ROM. Accessing the API through these tables provides scalability; while the API locations may change in future versions of the ROM, the API tables will not. The tables are split into two levels; the main table contains one pointer per peripheral which points to a secondary table that contains one pointer per API that is associated with that peripheral. The main table is located at 0x0100.0010, right after the Cortex-M3 vector table in the ROM. DriverLib functions are described in detail in the Stellaris® Peripheral Driver Library User's Guide. Additional APIs are available for graphics and USB functions, but are not preloaded into ROM. The Stellaris Graphics Library provides a set of graphics primitives and a widget set for creating graphical user interfaces on Stellaris microcontroller-based boards that have a graphical display (for more information, see the Stellaris® Graphics Library User's Guide). The Stellaris USB Library is a set 322 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller of data types and functions for creating USB Device, Host or On-The-Go (OTG) applications on Stellaris microcontroller-based boards (for more information, see the Stellaris® USB Library User's Guide). 7.2.2.3 Advanced Encryption Standard (AES) Cryptography Tables AES is a strong encryption method with reasonable performance and size. AES is fast in both hardware and software, is fairly easy to implement, and requires little memory. AES is ideal for applications that can use pre-arranged keys, such as setup during manufacturing or configuration. Four data tables used by the XySSL AES implementation are provided in the ROM. The first is the forward S-box substitution table, the second is the reverse S-box substitution table, the third is the forward polynomial table, and the final is the reverse polynomial table. See the Stellaris® ROM User’s Guide for more information on AES. 7.2.2.4 Cyclic Redundancy Check (CRC) Error Detection The CRC technique can be used to validate correct receipt of messages (nothing lost or modified in transit), to validate data after decompression, to validate that Flash memory contents have not been changed, and for other cases where the data needs to be validated. A CRC is preferred over a simple checksum (e.g. XOR all bits) because it catches changes more readily. See the Stellaris® ROM User’s Guide for more information on CRC. 7.2.3 Flash Memory At system clock speeds of 50 MHz and below, the Flash memory is read in a single cycle. The Flash memory is organized as a set of 1-KB blocks that can be individually erased. An individual 32-bit word can be programmed to change bits from 1 to 0. In addition, a write buffer provides the ability to concurrently program 32 continuous words in Flash memory. Erasing a block causes the entire contents of the block to be reset to all 1s. The 1-KB blocks are paired into sets of 2-KB blocks that can be individually protected. The protection allows blocks to be marked as read-only or execute-only, providing different levels of code protection. Read-only blocks cannot be erased or programmed, protecting the contents of those blocks from being modified. Execute-only blocks cannot be erased or programmed and can only be read by the controller instruction fetch mechanism, protecting the contents of those blocks from being read by either the controller or by a debugger. Caution – The Stellaris Flash memory array has ECC which uses a test port into the Flash memory to continually scan the array for ECC errors and to correct any that are detected. This operation is transparent to the microcontroller. The BIST must scan the entire memory array occasionally to ensure integrity, taking about five minutes to do so. In systems where the microcontroller is frequently powered for less than five minutes, power should be removed from the microcontroller in a controlled manner to ensure proper operation. This controlled manner can either be through entering Hibernate mode or software can request permission to power down the part using the USDREQ bit in the Flash Control (FCTL) register and wait to receive an acknowledge from the USDACK bit prior to removing power. If the microcontroller is powered down using this controlled method, the BIST engine keeps track of where it was in the memory array and it always scans the complete array after any aggregate of five minutes powered-on, regardless of the number of intervening power cycles. If the microcontroller is powered down before five minutes of being powered up, BIST starts again from wherever it left off before the last controlled power-down or from 0 if there never was a controlled power down. An occasional short power down is not a concern, but the microcontroller should not always be powered down frequently in an uncontrolled manner. The microcontroller can be power-cycled as frequently as necessary if it is powered-down in a controlled manner. July 03, 2014 323 Texas Instruments-Production Data Internal Memory 7.2.3.1 Prefetch Buffer The Flash memory controller has a prefetch buffer that is automatically used when the CPU frequency is greater than 50 MHz. In this mode, the Flash memory operates at half of the system clock. The prefetch buffer fetches two 32-bit words per clock allowing instructions to be fetched with no wait states while code is executing linearly. The fetch buffer includes a branch speculation mechanism that recognizes a branch and avoids extra wait states by not reading the next word pair. Also, short loop branches often stay in the buffer. As a result, some branches can be executed with no wait states. Other branches incur a single wait state. 7.2.3.2 Flash Memory Protection The user is provided two forms of Flash memory protection per 2-KB Flash memory block in six pairs of 32-bit wide registers. The policy for each protection form is controlled by individual bits (per policy per block) in the FMPPEn and FMPREn registers. ■ Flash Memory Protection Program Enable (FMPPEn): If a bit is set, the corresponding block may be programmed (written) or erased. If a bit is cleared, the corresponding block may not be changed. ■ Flash Memory Protection Read Enable (FMPREn): If a bit is set, the corresponding block may be executed or read by software or debuggers. If a bit is cleared, the corresponding block may only be executed, and contents of the memory block are prohibited from being read as data. The policies may be combined as shown in Table 7-1 on page 324. Table 7-1. Flash Memory Protection Policy Combinations FMPPEn FMPREn 0 0 Protection Execute-only protection. The block may only be executed and may not be written or erased. This mode is used to protect code. 1 0 The block may be written, erased or executed, but not read. This combination is unlikely to be used. 0 1 Read-only protection. The block may be read or executed but may not be written or erased. This mode is used to lock the block from further modification while allowing any read or execute access. 1 1 No protection. The block may be written, erased, executed or read. A Flash memory access that attempts to read a read-protected block (FMPREn bit is set) is prohibited and generates a bus fault. A Flash memory access that attempts to program or erase a program-protected block (FMPPEn bit is set) is prohibited and can optionally generate an interrupt (by setting the AMASK bit in the Flash Controller Interrupt Mask (FCIM) register) to alert software developers of poorly behaving software during the development and debug phases. Note that if a FMPREn bit is cleared, all read accesses to the Flash memory block are disallowed, including any data accesses. Care must be taken not to store required data in a Flash memory block that has the associated FMPREn bit cleared. The factory settings for the FMPREn and FMPPEn registers are a value of 1 for all implemented banks. These settings create a policy of open access and programmability. The register bits may be changed by clearing the specific register bit. The changes are effective immediately, but are not permanent until the register is committed (saved), at which point the bit change is permanent. If a bit is changed from a 1 to a 0 and not committed, it may be restored by executing any type of reset sequence. The changes are committed using the Flash Memory Control (FMC) register. Details on programming these bits are discussed in “Non-Volatile Register Programming” on page 327. 324 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller 7.2.3.3 Interrupts The Flash memory controller can generate interrupts when the following conditions are observed: ■ Programming Interrupt - signals when a program or erase action is complete. ■ Access Interrupt - signals when a program or erase action has been attempted on a 2-kB block of memory that is protected by its corresponding FMPPEn bit. The interrupt events that can trigger a controller-level interrupt are defined in the Flash Controller Masked Interrupt Status (FCMIS) register (see page 337) by setting the corresponding MASK bits. If interrupts are not used, the raw interrupt status is always visible via the Flash Controller Raw Interrupt Status (FCRIS) register (see page 336). Interrupts are always cleared (for both the FCMIS and FCRIS registers) by writing a 1 to the corresponding bit in the Flash Controller Masked Interrupt Status and Clear (FCMISC) register (see page 338). 7.2.3.4 Flash Memory Programming The Stellaris devices provide a user-friendly interface for Flash memory programming. All erase/program operations are handled via three registers: Flash Memory Address (FMA), Flash Memory Data (FMD), and Flash Memory Control (FMC). Note that if the debug capabilities of the microcontroller have been deactivated, resulting in a "locked" state, a recovery sequence must be performed in order to reactivate the debug module. See “Recovering a "Locked" Microcontroller” on page 183. During a Flash memory operation (write, page erase, or mass erase) access to the Flash memory is inhibited. As a result, instruction and literal fetches are held off until the Flash memory operation is complete. If instruction execution is required during a Flash memory operation, the code that is executing must be placed in SRAM and executed from there while the flash operation is in progress. Caution – The Flash memory is divided into sectors of electrically separated address ranges of 4 KB each, aligned on 4 KB boundaries. Erase/program operations on a 1-KB page have an electrical effect on the other three 1-KB pages within the sector. A specific 1-KB page must be erased after 6 total erase/program cycles occur to the other pages within its 4-KB sector. The following sequence of operations on a 4-KB sector of Flash memory (Page 0..3) provides an example: ■ Page 3 is erase and programmed with values. ■ Page 0, Page 1, and Page 2 are erased and then programmed with values. At this point Page 3 has been affected by 3 erase/program cycles. ■ Page 0, Page 1, and Page 2 are again erased and then programmed with values. At this point Page 3 has been affected by 6 erase/program cycles. ■ If the contents of Page 3 must continue to be valid, Page 3 must be erased and reprogrammed before any other page in this sector has another erase or program operation. To program a 32-bit word 1. Write source data to the FMD register. 2. Write the target address to the FMA register. July 03, 2014 325 Texas Instruments-Production Data Internal Memory 3. Write the Flash memory write key and the WRITE bit (a value of 0xA442.0001) to the FMC register. 4. Poll the FMC register until the WRITE bit is cleared. Important: To ensure proper operation, two writes to the same word must be separated by an ERASE. The following two sequences are allowed: ■ ERASE -> PROGRAM value -> PROGRAM 0x0000.0000 ■ ERASE -> PROGRAM value -> ERASE The following sequence is NOT allowed: ■ ERASE -> PROGRAM value -> PROGRAM value To perform an erase of a 1-KB page 1. Write the page address to the FMA register. 2. Write the Flash memory write key and the ERASE bit (a value of 0xA442.0002) to the FMC register. 3. Poll the FMC register until the ERASE bit is cleared or, alternatively, enable the programming interrupt using the PMASK bit in the FCIM register. To perform a mass erase of the Flash memory 1. Write the Flash memory write key and the MERASE bit (a value of 0xA442.0004) to the FMC register. 2. Poll the FMC register until the MERASE bit is cleared or, alternatively, enable the programming interrupt using the PMASK bit in the FCIM register. 7.2.3.5 32-Word Flash Memory Write Buffer A 32-word write buffer provides the capability to perform faster write accesses to the Flash memory by concurrently programing 32 words with a single buffered Flash memory write operation. The buffered Flash memory write operation takes the same amount of time as the single word write operation controlled by bit 0 in the FMC register. The data for the buffered write is written to the Flash Write Buffer (FWBn) registers. The registers are 32-word aligned with Flash memory, and therefore the register FWB0 corresponds with the address in FMA where bits [6:0] of FMA are all 0. FWB1 corresponds with the address in FMA + 0x4 and so on. Only the FWBn registers that have been updated since the previous buffered Flash memory write operation are written. The Flash Write Buffer Valid (FWBVAL) register shows which registers have been written since the last buffered Flash memory write operation. This register contains a bit for each of the 32 FWBn registers, where bit[n] of FWBVAL corresponds to FWBn. The FWBn register has been updated if the corresponding bit in the FWBVAL register is set. To program 32 words with a single buffered Flash memory write operation 1. Write the source data to the FWBn registers. 326 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller 2. Write the target address to the FMA register. This must be a 32-word aligned address (that is, bits [6:0] in FMA must be 0s). 3. Write the Flash memory write key and the WRBUF bit (a value of 0xA442.0001) to the FMC2 register. 4. Poll the FMC2 register until the WRBUF bit is cleared or wait for the PMIS interrupt to be signaled. 7.2.3.6 Non-Volatile Register Programming Note: The Boot Configuration (BOOTCFG) register requires a POR before the committed changes take effect. This section discusses how to update the registers shown in Table 7-2 on page 328 that are resident within the Flash memory itself. These registers exist in a separate space from the main Flash memory array and are not affected by an ERASE or MASS ERASE operation. With the exception of the Boot Configuration (BOOTCFG) register, the settings in these registers can be written, their functions verified, and their values read back before they are committed, at which point they become non-volatile. If a value in one of these registers has not been committed, any type of reset restores the last committed value or the default value if the register has never been committed. Once the register contents are committed, the only way to restore the factory default values is to perform the sequence described in “Recovering a "Locked" Microcontroller” on page 183. To write to a non-volatile register: ■ Bits can only be changed from 1 to 0. ■ For all registers except the BOOTCFG register, write the data to the register address provided in the register description. For the BOOTCFG register, write the data to the FMD register. ■ The registers can be read to verify their contents. To verify what is to be stored in the BOOTCFG register, read the FMD register. Reading the BOOTCFG register returns the previously committed value or the default value if the register has never been committed. ■ The new values are effectively immediately for all registers except BOOTCFG, as the new value for the register is not stored in the register until it has been committed. ■ Prior to committing the register value, any type of reset restores the last committed value or the default value if the register has never been committed. To commit a new value to a non-volatile register: ■ Write the data as described above. ■ Write to the FMA register the value shown in Table 7-2 on page 328. ■ Write the Flash memory write key and set the COMT bit in the FMC register. These values must be written to the FMC register at the same time. ■ Committing a non-volatile register has the same timing as a write to regular Flash memory, defined by TPROG, as shown in Table 25-20 on page 1232. Software can poll the COMT bit in the FMC register to determine when the operation is complete, or an interrupt can be enabled by setting the PMASK bit in the FCIM register. ■ When committing the BOOTCFG register, the INVDRIS bit in the FCRIS register is set if a bit that has already been committed as a 0 is attempted to be committed as a 1. July 03, 2014 327 Texas Instruments-Production Data Internal Memory ■ Once the value has been committed, any type of reset has no effect on the register contents. ■ Changes to the BOOTCFG register are effective after the next reset. ■ The NW bit in the USER_REG0, USER_REG1, USER_REG2, USER_REG3, and BOOTCFG registers is cleared when the register is committed. Once this bit is cleared, additional changes to the register are not allowed. Important: After being committed, these registers can only be restored to their factory default values by performing the sequence described in “Recovering a "Locked" Microcontroller” on page 183. The mass erase of the main Flash memory array caused by the sequence is performed prior to restoring these registers. Table 7-2. User-Programmable Flash Memory Resident Registers Register to be Committed 7.3 FMA Value Data Source FMPRE0 0x0000.0000 FMPRE0 FMPRE1 0x0000.0002 FMPRE1 FMPRE2 0x0000.0004 FMPRE2 FMPRE3 0x0000.0006 FMPRE3 FMPRE4 0x0000.0008 FMPRE4 FMPRE5 0x0000.000A FMPRE5 FMPPE0 0x0000.0001 FMPPE0 FMPPE1 0x0000.0003 FMPPE1 FMPPE2 0x0000.0005 FMPPE2 FMPPE3 0x0000.0007 FMPPE3 FMPRE4 0x0000.0009 FMPRE4 FMPRE5 0x0000.000B FMPRE5 USER_REG0 0x8000.0000 USER_REG0 USER_REG1 0x8000.0001 USER_REG1 USER_REG2 0x8000.0002 USER_REG2 USER_REG3 0x8000.0003 USER_REG3 BOOTCFG 0x7510.0000 FMD Register Map Table 7-3 on page 328 lists the ROM Controller register and the Flash memory and control registers. The offset listed is a hexadecimal increment to the register's address. The Flash memory register offsets are relative to the Flash memory control base address of 0x400F.D000. The ROM and Flash memory protection register offsets are relative to the System Control base address of 0x400F.E000. Table 7-3. Flash Register Map Offset Name Type Reset Description See page Flash Memory Registers (Flash Control Offset) 0x000 FMA R/W 0x0000.0000 Flash Memory Address 331 0x004 FMD R/W 0x0000.0000 Flash Memory Data 332 328 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Table 7-3. Flash Register Map (continued) Description See page Offset Name Type Reset 0x008 FMC R/W 0x0000.0000 Flash Memory Control 333 0x00C FCRIS RO 0x0000.0000 Flash Controller Raw Interrupt Status 336 0x010 FCIM R/W 0x0000.0000 Flash Controller Interrupt Mask 337 0x014 FCMISC R/W1C 0x0000.0000 Flash Controller Masked Interrupt Status and Clear 338 0x020 FMC2 R/W 0x0000.0000 Flash Memory Control 2 339 0x030 FWBVAL R/W 0x0000.0000 Flash Write Buffer Valid 340 0x0F8 FCTL R/W 0x0000.0000 Flash Control 341 0x100 0x17C FWBn R/W 0x0000.0000 Flash Write Buffer n 342 ROM Control 343 Memory Registers (System Control Offset) 0x0F0 RMCTL R/W1C - 0x130 FMPRE0 R/W 0xFFFF.FFFF Flash Memory Protection Read Enable 0 344 0x200 FMPRE0 R/W 0xFFFF.FFFF Flash Memory Protection Read Enable 0 344 0x134 FMPPE0 R/W 0xFFFF.FFFF Flash Memory Protection Program Enable 0 345 0x400 FMPPE0 R/W 0xFFFF.FFFF Flash Memory Protection Program Enable 0 345 0x1D0 BOOTCFG R/W 0xFFFF.FFFE Boot Configuration 346 0x1E0 USER_REG0 R/W 0xFFFF.FFFF User Register 0 348 0x1E4 USER_REG1 R/W 0xFFFF.FFFF User Register 1 349 0x1E8 USER_REG2 R/W 0xFFFF.FFFF User Register 2 350 0x1EC USER_REG3 R/W 0xFFFF.FFFF User Register 3 351 0x204 FMPRE1 R/W 0xFFFF.FFFF Flash Memory Protection Read Enable 1 352 0x208 FMPRE2 R/W 0xFFFF.FFFF Flash Memory Protection Read Enable 2 353 0x20C FMPRE3 R/W 0xFFFF.FFFF Flash Memory Protection Read Enable 3 354 0x210 FMPRE4 R/W 0xFFFF.FFFF Flash Memory Protection Read Enable 4 355 0x214 FMPRE5 R/W 0xFFFF.FFFF Flash Memory Protection Read Enable 5 356 0x218 FMPRE6 R/W 0x0000.0000 Flash Memory Protection Read Enable 6 357 0x21C FMPRE7 R/W 0x0000.0000 Flash Memory Protection Read Enable 7 358 0x404 FMPPE1 R/W 0xFFFF.FFFF Flash Memory Protection Program Enable 1 359 0x408 FMPPE2 R/W 0xFFFF.FFFF Flash Memory Protection Program Enable 2 360 0x40C FMPPE3 R/W 0xFFFF.FFFF Flash Memory Protection Program Enable 3 361 0x410 FMPPE4 R/W 0xFFFF.FFFF Flash Memory Protection Program Enable 4 362 0x414 FMPPE5 R/W 0xFFFF.FFFF Flash Memory Protection Program Enable 5 363 July 03, 2014 329 Texas Instruments-Production Data Internal Memory Table 7-3. Flash Register Map (continued) See page Offset Name Type Reset 0x418 FMPPE6 R/W 0x0000.0000 Flash Memory Protection Program Enable 6 364 0x41C FMPPE7 R/W 0x0000.0000 Flash Memory Protection Program Enable 7 365 7.4 Description Flash Memory Register Descriptions (Flash Control Offset) This section lists and describes the Flash Memory registers, in numerical order by address offset. Registers in this section are relative to the Flash control base address of 0x400F.D000. 330 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 1: Flash Memory Address (FMA), offset 0x000 During a write operation, this register contains a 4-byte-aligned address and specifies where the data is written. During erase operations, this register contains a 1 KB-aligned CPU byte address and specifies which block is erased. Note that the alignment requirements must be met by software or the results of the operation are unpredictable. Flash Memory Address (FMA) Base 0x400F.D000 Offset 0x000 Type R/W, reset 0x0000.0000 31 30 29 28 27 26 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 25 24 23 22 21 20 19 18 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 R/W 0 R/W 0 R/W 0 10 9 8 7 6 5 4 3 2 1 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 reserved Type Reset 17 16 OFFSET OFFSET Type Reset Bit/Field Name Type Reset Description 31:19 reserved RO 0x0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 18:0 OFFSET R/W 0x0 Address Offset Address offset in Flash memory where operation is performed, except for non-volatile registers (see “Non-Volatile Register Programming” on page 327 for details on values for this field). July 03, 2014 331 Texas Instruments-Production Data Internal Memory Register 2: Flash Memory Data (FMD), offset 0x004 This register contains the data to be written during the programming cycle or read during the read cycle. Note that the contents of this register are undefined for a read access of an execute-only block. This register is not used during erase cycles. Flash Memory Data (FMD) Base 0x400F.D000 Offset 0x004 Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 DATA Type Reset DATA Type Reset Bit/Field Name Type 31:0 DATA R/W Reset Description 0x0000.0000 Data Value Data value for write operation. 332 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 3: Flash Memory Control (FMC), offset 0x008 When this register is written, the Flash memory controller initiates the appropriate access cycle for the location specified by the Flash Memory Address (FMA) register (see page 331). If the access is a write access, the data contained in the Flash Memory Data (FMD) register (see page 332) is written to the specified address. This register must be the final register written and initiates the memory operation. The four control bits in the lower byte of this register are used to initiate memory operations. Care must be taken not to set multiple control bits as the results of such an operation are unpredictable. Caution – If any of bits [15:4] are written to 1, the device may become inoperable. These bits should always be written to 0. In all registers, the value of a reserved bit should be preserved across a read-modify-write operation. Flash Memory Control (FMC) Base 0x400F.D000 Offset 0x008 Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 WO 0 WO 0 WO 0 WO 0 WO 0 WO 0 WO 0 WO 0 WO 0 WO 0 WO 0 WO 0 WO 0 WO 0 WO 0 WO 0 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 COMT MERASE ERASE WRITE RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 R/W 0 R/W 0 R/W 0 R/W 0 WRKEY Type Reset reserved Type Reset Bit/Field Name Type Reset 31:16 WRKEY WO 0x0000 Description Flash Memory Write Key This field contains a write key, which is used to minimize the incidence of accidental Flash memory writes. The value 0xA442 must be written into this field for a Flash memory write to occur. Writes to the FMC register without this WRKEY value are ignored. A read of this field returns the value 0. 15:4 reserved RO 0x00 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. July 03, 2014 333 Texas Instruments-Production Data Internal Memory Bit/Field Name Type Reset 3 COMT R/W 0 Description Commit Register Value This bit is used to commit writes to Flash-memory-resident registers and to monitor the progress of that process. Value Description 1 Set this bit to commit (write) the register value to a Flash-memory-resident register. When read, a 1 indicates that the previous commit access is not complete. 0 A write of 0 has no effect on the state of this bit. When read, a 0 indicates that the previous commit access is complete. See “Non-Volatile Register Programming” on page 327 for more information on programming Flash-memory-resident registers. 2 MERASE R/W 0 Mass Erase Flash Memory This bit is used to mass erase the Flash main memory and to monitor the progress of that process. Value Description 1 Set this bit to erase the Flash main memory. When read, a 1 indicates that the previous mass erase access is not complete. 0 A write of 0 has no effect on the state of this bit. When read, a 0 indicates that the previous mass erase access is complete. For information on erase time, see “Flash Memory” on page 1232. 1 ERASE R/W 0 Erase a Page of Flash Memory This bit is used to erase a page of Flash memory and to monitor the progress of that process. Value Description 1 Set this bit to erase the Flash memory page specified by the contents of the FMA register. When read, a 1 indicates that the previous page erase access is not complete. 0 A write of 0 has no effect on the state of this bit. When read, a 0 indicates that the previous page erase access is complete. For information on erase time, see “Flash Memory” on page 1232. 334 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Bit/Field Name Type Reset 0 WRITE R/W 0 Description Write a Word into Flash Memory This bit is used to write a word into Flash memory and to monitor the progress of that process. Value Description 1 Set this bit to write the data stored in the FMD register into the Flash memory location specified by the contents of the FMA register. When read, a 1 indicates that the write update access is not complete. 0 A write of 0 has no effect on the state of this bit. When read, a 0 indicates that the previous write update access is complete. For information on programming time, see “Flash Memory” on page 1232. July 03, 2014 335 Texas Instruments-Production Data Internal Memory Register 4: Flash Controller Raw Interrupt Status (FCRIS), offset 0x00C This register indicates that the Flash memory controller has an interrupt condition. An interrupt is sent to the interrupt controller only if the corresponding FCIM register bit is set. Flash Controller Raw Interrupt Status (FCRIS) Base 0x400F.D000 Offset 0x00C Type RO, reset 0x0000.0000 31 30 29 28 27 26 25 24 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 8 7 6 5 4 3 2 1 0 PRIS ARIS RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 reserved Type Reset reserved Type Reset Bit/Field Name Type Reset 31:2 reserved RO 0x0000.000 1 PRIS RO 0 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. Programming Raw Interrupt Status This bit provides status on programming cycles which are write or erase actions generated through the FMC or FMC2 register bits (see page 333 and page 339). Value Description 1 The programming or erase cycle has completed. 0 The programming or erase cycle has not completed. This status is sent to the interrupt controller when the PMASK bit in the FCIM register is set. This bit is cleared by writing a 1 to the PMISC bit in the FCMISC register. 0 ARIS RO 0 Access Raw Interrupt Status Value Description 1 A program or erase action was attempted on a block of Flash memory that contradicts the protection policy for that block as set in the FMPPEn registers. 0 No access has tried to improperly program or erase the Flash memory. This status is sent to the interrupt controller when the AMASK bit in the FCIM register is set. This bit is cleared by writing a 1 to the AMISC bit in the FCMISC register. 336 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 5: Flash Controller Interrupt Mask (FCIM), offset 0x010 This register controls whether the Flash memory controller generates interrupts to the controller. Flash Controller Interrupt Mask (FCIM) Base 0x400F.D000 Offset 0x010 Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 8 7 6 5 4 3 2 1 0 PMASK AMASK RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 R/W 0 R/W 0 reserved Type Reset reserved Type Reset Bit/Field Name Type Reset 31:2 reserved RO 0x0000.000 1 PMASK R/W 0 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. Programming Interrupt Mask This bit controls the reporting of the programming raw interrupt status to the interrupt controller. Value Description 0 AMASK R/W 0 1 An interrupt is sent to the interrupt controller when the PRIS bit is set. 0 The PRIS interrupt is suppressed and not sent to the interrupt controller. Access Interrupt Mask This bit controls the reporting of the access raw interrupt status to the interrupt controller. Value Description 1 An interrupt is sent to the interrupt controller when the ARIS bit is set. 0 The ARIS interrupt is suppressed and not sent to the interrupt controller. July 03, 2014 337 Texas Instruments-Production Data Internal Memory Register 6: Flash Controller Masked Interrupt Status and Clear (FCMISC), offset 0x014 This register provides two functions. First, it reports the cause of an interrupt by indicating which interrupt source or sources are signalling the interrupt. Second, it serves as the method to clear the interrupt reporting. Flash Controller Masked Interrupt Status and Clear (FCMISC) Base 0x400F.D000 Offset 0x014 Type R/W1C, reset 0x0000.0000 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 RO 0 RO 0 reserved Type Reset RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 8 7 6 5 4 3 2 reserved Type Reset RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 Bit/Field Name Type Reset 31:2 reserved RO 0x0000.000 1 PMISC R/W1C 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 1 0 PMISC AMISC R/W1C 0 R/W1C 0 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. Programming Masked Interrupt Status and Clear Value Description 1 When read, a 1 indicates that an unmasked interrupt was signaled because a programming cycle completed. Writing a 1 to this bit clears PMISC and also the PRIS bit in the FCRIS register (see page 336). 0 When read, a 0 indicates that a programming cycle complete interrupt has not occurred. A write of 0 has no effect on the state of this bit. 0 AMISC R/W1C 0 Access Masked Interrupt Status and Clear Value Description 1 When read, a 1 indicates that an unmasked interrupt was signaled because a program or erase action was attempted on a block of Flash memory that contradicts the protection policy for that block as set in the FMPPEn registers. Writing a 1 to this bit clears AMISC and also the ARIS bit in the FCRIS register (see page 336). 0 When read, a 0 indicates that no improper accesses have occurred. A write of 0 has no effect on the state of this bit. 338 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 7: Flash Memory Control 2 (FMC2), offset 0x020 When this register is written, the Flash memory controller initiates the appropriate access cycle for the location specified by the Flash Memory Address (FMA) register (see page 331). If the access is a write access, the data contained in the Flash Write Buffer (FWB) registers is written. This register must be the final register written as it initiates the memory operation. Flash Memory Control 2 (FMC2) Base 0x400F.D000 Offset 0x020 Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 WO 0 WO 0 WO 0 WO 0 WO 0 WO 0 WO 0 WO 0 WO 0 8 7 6 5 4 3 2 1 WRKEY Type Reset WO 0 WO 0 WO 0 WO 0 WO 0 WO 0 WO 0 15 14 13 12 11 10 9 reserved Type Reset RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 Bit/Field Name Type Reset 31:16 WRKEY WO 0x0000 RO 0 0 WRBUF RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 R/W 0 Description Flash Memory Write Key This field contains a write key, which is used to minimize the incidence of accidental Flash memory writes. The value 0xA442 must be written into this field for a write to occur. Writes to the FMC2 register without this WRKEY value are ignored. A read of this field returns the value 0. 15:1 reserved RO 0x000 0 WRBUF R/W 0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. Buffered Flash Memory Write This bit is used to start a buffered write to Flash memory. Value Description 1 Set this bit to write the data stored in the FWBn registers to the location specified by the contents of the FMA register. When read, a 1 indicates that the previous buffered Flash memory write access is not complete. 0 A write of 0 has no effect on the state of this bit. When read, a 0 indicates that the previous buffered Flash memory write access is complete. For information on programming time, see “Flash Memory” on page 1232. July 03, 2014 339 Texas Instruments-Production Data Internal Memory Register 8: Flash Write Buffer Valid (FWBVAL), offset 0x030 This register provides a bitwise status of which FWBn registers have been written by the processor since the last write of the Flash memory write buffer. The entries with a 1 are written on the next write of the Flash memory write buffer. This register is cleared after the write operation by hardware. A protection violation on the write operation also clears this status. Software can program the same 32 words to various Flash memory locations by setting the FWB[n] bits after they are cleared by the write operation. The next write operation then uses the same data as the previous one. In addition, if a FWBn register change should not be written to Flash memory, software can clear the corresponding FWB[n] bit to preserve the existing data when the next write operation occurs. Flash Write Buffer Valid (FWBVAL) Base 0x400F.D000 Offset 0x030 Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 FWB[n] Type Reset R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 FWB[n] Type Reset R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 Bit/Field Name Type Reset 31:0 FWB[n] R/W 0x0 R/W 0 Description Flash Memory Write Buffer Value Description 1 The corresponding FWBn register has been updated since the last buffer write operation and is ready to be written to Flash memory. 0 The corresponding FWBn register has no new data to be written. Bit 0 corresponds to FWB0, offset 0x100, and bit 31 corresponds to FWB31, offset 0x13C. 340 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 9: Flash Control (FCTL), offset 0x0F8 This register is used to ensure that the microcontroller is powered down in a controlled fashion in systems where power is cycled more frequently than once every five minutes. The USDREQ bit should be set to indicate that power is going to be turned off. Software should poll the USDACK bit to determine when it is acceptable to power down. Note that this power-down process is not required if the microcontroller enters Hibernate mode prior to power being removed. Flash Control (FCTL) Base 0x400F.D000 Offset 0x0F8 Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 RO 0 RO 0 1 0 reserved Type Reset RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 8 7 6 5 4 3 2 reserved Type Reset RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 Bit/Field Name Type Reset 31:2 reserved RO 0x0000.000 1 USDACK RO 0 USDACK USDREQ RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 R/W 0 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. User Shut Down Acknowledge Value Description 1 The microcontroller can be powered down. 0 The microcontroller cannot yet be powered down. This bit should be set within 50 ms of setting the USDREQ bit. 0 USDREQ R/W 0 User Shut Down Request Value Description 1 Requests permission to power down the microcontroller. 0 No effect. July 03, 2014 341 Texas Instruments-Production Data Internal Memory Register 10: Flash Write Buffer n (FWBn), offset 0x100 - 0x17C These 32 registers hold the contents of the data to be written into the Flash memory on a buffered Flash memory write operation. The offset selects one of the 32-bit registers. Only FWBn registers that have been updated since the preceding buffered Flash memory write operation are written into the Flash memory, so it is not necessary to write the entire bank of registers in order to write 1 or 2 words. The FWBn registers are written into the Flash memory with the FWB0 register corresponding to the address contained in FMA. FWB1 is written to the address FMA+0x4 etc. Note that only data bits that are 0 result in the Flash memory being modified. A data bit that is 1 leaves the content of the Flash memory bit at its previous value. Flash Write Buffer n (FWBn) Base 0x400F.D000 Offset 0x100 - 0x17C Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 DATA Type Reset DATA Type Reset Bit/Field Name Type 31:0 DATA R/W Reset Description 0x0000.0000 Data Data to be written into the Flash memory. 7.5 Memory Register Descriptions (System Control Offset) The remainder of this section lists and describes the registers that reside in the System Control address space, in numerical order by address offset. Registers in this section are relative to the System Control base address of 0x400F.E000. 342 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 11: ROM Control (RMCTL), offset 0x0F0 This register provides control of the ROM controller state. This register offset is relative to the System Control base address of 0x400F.E000. At reset, the ROM is mapped over the Flash memory so that the ROM boot sequence is always executed. The boot sequence executed from ROM is as follows: 1. The BA bit (below) is cleared such that ROM is mapped to 0x01xx.xxxx and Flash memory is mapped to address 0x0. 2. The BOOTCFG register is read. If the EN bit is clear, the status of the specified GPIO pin is compared with the specified polarity. If the status matches the specified polarity, the ROM is mapped to address 0x0000.0000 and execution continues out of the ROM Boot Loader. 3. If the status doesn't match the specified polarity, the data at address 0x0000.0004 is read, and if the data at this address is 0xFFFF.FFFF, the ROM is mapped to address 0x0000.0000 and execution continues out of the ROM Boot Loader. 4. If there is data at address 0x0000.0004 that is not 0xFFFF.FFFF, the stack pointer (SP) is loaded from Flash memory at address 0x0000.0000 and the program counter (PC) is loaded from address 0x0000.0004. The user application begins executing. ROM Control (RMCTL) Base 0x400F.E000 Offset 0x0F0 Type R/W1C, reset 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 RO 0 reserved Type Reset RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 8 7 6 5 4 3 2 1 reserved Type Reset RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 Bit/Field Name Type Reset 31:1 reserved RO 0x0000.000 0 BA R/W1C 1 RO 0 0 BA RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 R/W1C 1 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. Boot Alias Value Description 1 The microcontroller's ROM appears at address 0x0. 0 The Flash memory is at address 0x0. This bit is cleared by writing a 1 to this bit position. July 03, 2014 343 Texas Instruments-Production Data Internal Memory Register 12: Flash Memory Protection Read Enable 0 (FMPRE0), offset 0x130 and 0x200 Note: This register is aliased for backwards compatability. Note: Offset is relative to System Control base address of 0x400FE000. This register stores the read-only protection bits for each 2-KB flash block (FMPPEn stores the execute-only bits). Flash memory up to a total of 64 KB is controlled by this register. Other FMPREn registers (if any) provide protection for other 64K blocks. This register is loaded during the power-on reset sequence. The factory settings for the FMPREn and FMPPEn registers are a value of 1 for all implemented banks. This achieves a policy of open access and programmability. The register bits may be changed by writing the specific register bit. However, this register is R/W0; the user can only change the protection bit from a 1 to a 0 (and may NOT change a 0 to a 1). The changes are not permanent until the register is committed (saved), at which point the bit change is permanent. If a bit is changed from a 1 to a 0 and not committed, it may be restored by executing a power-on reset sequence. The reset value shown only applies to power-on reset; any other type of reset does not affect this register. Once committed, the only way to restore the factory default value of this register is to perform the sequence detailed in “Recovering a "Locked" Microcontroller” on page 183. For additional information, see “Flash Memory Protection” on page 324. Flash Memory Protection Read Enable 0 (FMPRE0) Base 0x400F.E000 Offset 0x130 and 0x200 Type R/W, reset 0xFFFF.FFFF 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 READ_ENABLE Type Reset R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 15 14 13 12 11 10 9 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 8 7 6 5 4 3 2 1 0 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 READ_ENABLE Type Reset R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 Bit/Field Name Type 31:0 READ_ENABLE R/W R/W 1 Reset R/W 1 R/W 1 Description 0xFFFFFFFF Flash Read Enable Configures 2-KB flash blocks to be read or executed only. The policies may be combined as shown in Table 7-1 on page 324. Value Description 0xFFFFFFFF Bits [31:0] each enable protection on a 2-KB block of Flash memory up to the total of 64 KB. 344 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 13: Flash Memory Protection Program Enable 0 (FMPPE0), offset 0x134 and 0x400 Note: This register is aliased for backwards compatability. Note: Offset is relative to System Control base address of 0x400FE000. This register stores the execute-only protection bits for each 2-KB flash block (FMPREn stores the execute-only bits). Flash memory up to a total of 64 KB is controlled by this register. Other FMPPEn registers (if any) provide protection for other 64K blocks. This register is loaded during the power-on reset sequence. The factory settings for the FMPREn and FMPPEn registers are a value of 1 for all implemented banks. This achieves a policy of open access and programmability. The register bits may be changed by writing the specific register bit. However, this register is R/W0; the user can only change the protection bit from a 1 to a 0 (and may NOT change a 0 to a 1). The changes are not permanent until the register is committed (saved), at which point the bit change is permanent. If a bit is changed from a 1 to a 0 and not committed, it may be restored by executing a power-on reset sequence. The reset value shown only applies to power-on reset; any other type of reset does not affect this register. Once committed, the only way to restore the factory default value of this register is to perform the sequence detailed in “Recovering a "Locked" Microcontroller” on page 183. For additional information, see “Flash Memory Protection” on page 324. Flash Memory Protection Program Enable 0 (FMPPE0) Base 0x400F.E000 Offset 0x134 and 0x400 Type R/W, reset 0xFFFF.FFFF 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 PROG_ENABLE Type Reset R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 15 14 13 12 11 10 9 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 8 7 6 5 4 3 2 1 0 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 PROG_ENABLE Type Reset R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 Bit/Field Name Type 31:0 PROG_ENABLE R/W R/W 1 Reset R/W 1 R/W 1 Description 0xFFFFFFFF Flash Programming Enable Configures 2-KB flash blocks to be execute only. The policies may be combined as shown in Table 7-1 on page 324. Value Description 0xFFFFFFFF Bits [31:0] each enable protection on a 2-KB block of Flash memory up to the total of 64 KB. July 03, 2014 345 Texas Instruments-Production Data Internal Memory Register 14: Boot Configuration (BOOTCFG), offset 0x1D0 Note: Offset is relative to System Control base address of 0x400FE000. This register provides configuration of a GPIO pin to enable the ROM Boot Loader as well as a write-once mechanism to disable external debugger access to the device. Upon reset, the user has the opportunity to direct the core to execute the ROM Boot Loader or the application in Flash memory by using any GPIO signal from Ports A-H as configured by the bits in this register. If the EN bit is set or the specified pin does not have the required polarity, the system control module checks address 0x000.0004 to see if the Flash memory has a valid reset vector. If the data at address 0x0000.0004 is 0xFFFF.FFFF, then it is assumed that the Flash memory has not yet been programmed, and the core executes the ROM Boot Loader. The DBG0 bit (bit 0) is set to 0 from the factory and the DBG1 bit (bit 1) is set to 1, which enables external debuggers. Clearing the DBG1 bit disables any external debugger access to the device permanently, starting with the next power-up cycle of the device. The NW bit (bit 31) indicates that the register has not yet been committed and is controlled through hardware to ensure that the register is only committed once. Prior to being committed, bits can only be changed from 1 to 0. The reset value shown only applies to power-on reset; any other type of reset does not affect this register. Once committed, the only way to restore the factory default value of this register is to perform the sequence detailed in “Recovering a "Locked" Microcontroller” on page 183. Boot Configuration (BOOTCFG) Base 0x400F.E000 Offset 0x1D0 Type R/W, reset 0xFFFF.FFFE 31 30 29 28 27 26 25 24 NW Type Reset R/W 1 15 RO 1 RO 1 RO 1 14 13 12 PORT Type Reset R/W 1 23 22 21 20 19 18 17 16 RO 1 RO 1 reserved R/W 1 RO 1 RO 1 11 10 PIN R/W 1 R/W 1 R/W 1 R/W 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 7 6 5 4 3 2 9 8 POL EN R/W 1 R/W 1 reserved RO 1 Bit/Field Name Type Reset Description 31 NW R/W 1 Not Written RO 1 RO 1 RO 1 RO 1 RO 1 1 0 DBG1 DBG0 R/W 1 R/W 0 When set, this bit indicates that this 32-bit register has not been committed. When clear, this bit specifies that this register has been committed and may not be committed again. 30:16 reserved RO 0x7FFF Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 346 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Bit/Field Name Type Reset 15:13 PORT R/W 0x7 Description Boot GPIO Port This field selects the port of the GPIO port pin that enables the ROM boot loader at reset. Value Description 12:10 PIN R/W 0x7 0x0 Port A 0x1 Port B 0x2 Port C 0x3 Port D 0x4 Port E 0x5 Port F 0x6 Port G 0x7 Port H Boot GPIO Pin This field selects the pin number of the GPIO port pin that enables the ROM boot loader at reset. Value Description 9 POL R/W 0x1 0x0 Pin 0 0x1 Pin 1 0x2 Pin 2 0x3 Pin 3 0x4 Pin 4 0x5 Pin 5 0x6 Pin 6 0x7 Pin 7 Boot GPIO Polarity When set, this bit selects a high level for the GPIO port pin to enable the ROM boot loader at reset. When clear, this bit selects a low level for the GPIO port pin. 8 EN R/W 0x1 Boot GPIO Enable Clearing this bit enables the use of a GPIO pin to enable the ROM Boot Loader at reset. When this bit is set, the contents of address 0x0000.0004 are checked to see if the Flash memory has been programmed. If the contents are not 0xFFFF.FFFF, the core executes out of Flash memory. If the Flash has not been programmed, the core executes out of ROM. 7:2 reserved RO 0x3F 1 DBG1 R/W 1 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. Debug Control 1 The DBG1 bit must be 1 and DBG0 must be 0 for debug to be available. 0 DBG0 R/W 0x0 Debug Control 0 The DBG1 bit must be 1 and DBG0 must be 0 for debug to be available. July 03, 2014 347 Texas Instruments-Production Data Internal Memory Register 15: User Register 0 (USER_REG0), offset 0x1E0 Note: Offset is relative to System Control base address of 0x400FE000. This register provides 31 bits of user-defined data that is non-volatile and can only be committed once. Bit 31 indicates that the register is available to be committed and is controlled through hardware to ensure that the register is only committed once. Prior to being committed, bits can only be changed from 1 to 0. The reset value shown only applies to power-on reset; any other type of reset does not affect this register. The write-once characteristics of this register are useful for keeping static information like communication addresses that need to be unique per part and would otherwise require an external EEPROM or other non-volatile device. Once committed, the only way to restore the factory default value of this register is to perform the sequence detailed in “Recovering a "Locked" Microcontroller” on page 183. User Register 0 (USER_REG0) Base 0x400F.E000 Offset 0x1E0 Type R/W, reset 0xFFFF.FFFF 31 30 29 28 27 26 25 24 NW Type Reset 23 22 21 20 19 18 17 16 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 7 6 5 4 3 2 1 0 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 DATA R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 15 14 13 12 11 10 9 8 DATA Type Reset R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 Bit/Field Name Type Reset Description 31 NW R/W 1 Not Written When set, this bit indicates that this 32-bit register has not been committed. When clear, this bit specifies that this register has been committed and may not be committed again. 30:0 DATA R/W 0x7FFFFFFF User Data Contains the user data value. This field is initialized to all 1s and can only be committed once. 348 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 16: User Register 1 (USER_REG1), offset 0x1E4 Note: Offset is relative to System Control base address of 0x400FE000. This register provides 31 bits of user-defined data that is non-volatile and can only be written once. Bit 31 indicates that the register is available to be written and is controlled through hardware to ensure that the register is only written once. The write-once characteristics of this register are useful for keeping static information like communication addresses that need to be unique per part and would otherwise require an external EEPROM or other non-volatile device. User Register 1 (USER_REG1) Base 0x400F.E000 Offset 0x1E4 Type R/W, reset 0xFFFF.FFFF 31 30 29 28 27 26 25 24 NW Type Reset 23 22 21 20 19 18 17 16 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 7 6 5 4 3 2 1 0 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 DATA R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 15 14 13 12 11 10 9 8 DATA Type Reset R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 Bit/Field Name Type Reset Description 31 NW R/W 1 Not Written When set, this bit indicates that this 32-bit register has not been committed. When clear, this bit specifies that this register has been committed and may not be committed again. 30:0 DATA R/W 0x7FFFFFFF User Data Contains the user data value. This field is initialized to all 1s and can only be committed once. July 03, 2014 349 Texas Instruments-Production Data Internal Memory Register 17: User Register 2 (USER_REG2), offset 0x1E8 Note: Offset is relative to System Control base address of 0x400FE000. This register provides 31 bits of user-defined data that is non-volatile and can only be written once. Bit 31 indicates that the register is available to be written and is controlled through hardware to ensure that the register is only written once. The write-once characteristics of this register are useful for keeping static information like communication addresses that need to be unique per part and would otherwise require an external EEPROM or other non-volatile device. User Register 2 (USER_REG2) Base 0x400F.E000 Offset 0x1E8 Type R/W, reset 0xFFFF.FFFF 31 30 29 28 27 26 25 24 NW Type Reset 23 22 21 20 19 18 17 16 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 7 6 5 4 3 2 1 0 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 DATA R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 15 14 13 12 11 10 9 8 DATA Type Reset R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 Bit/Field Name Type Reset Description 31 NW R/W 1 Not Written When set, this bit indicates that this 32-bit register has not been committed. When clear, this bit specifies that this register has been committed and may not be committed again. 30:0 DATA R/W 0x7FFFFFFF User Data Contains the user data value. This field is initialized to all 1s and can only be committed once. 350 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 18: User Register 3 (USER_REG3), offset 0x1EC Note: Offset is relative to System Control base address of 0x400FE000. This register provides 31 bits of user-defined data that is non-volatile and can only be written once. Bit 31 indicates that the register is available to be written and is controlled through hardware to ensure that the register is only written once. The write-once characteristics of this register are useful for keeping static information like communication addresses that need to be unique per part and would otherwise require an external EEPROM or other non-volatile device. User Register 3 (USER_REG3) Base 0x400F.E000 Offset 0x1EC Type R/W, reset 0xFFFF.FFFF 31 30 29 28 27 26 25 24 NW Type Reset 23 22 21 20 19 18 17 16 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 7 6 5 4 3 2 1 0 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 DATA R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 15 14 13 12 11 10 9 8 DATA Type Reset R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 Bit/Field Name Type Reset Description 31 NW R/W 1 Not Written When set, this bit indicates that this 32-bit register has not been committed. When clear, this bit specifies that this register has been committed and may not be committed again. 30:0 DATA R/W 0x7FFFFFFF User Data Contains the user data value. This field is initialized to all 1s and can only be committed once. July 03, 2014 351 Texas Instruments-Production Data Internal Memory Register 19: Flash Memory Protection Read Enable 1 (FMPRE1), offset 0x204 Note: Offset is relative to System Control base address of 0x400FE000. This register stores the read-only protection bits for each 2-KB flash block (FMPPEn stores the execute-only bits). Flash memory up to a total of 64 KB is controlled by this register. Other FMPREn registers (if any) provide protection for other 64K blocks. This register is loaded during the power-on reset sequence. The factory settings for the FMPREn and FMPPEn registers are a value of 1 for all implemented banks. This achieves a policy of open access and programmability. The register bits may be changed by writing the specific register bit. However, this register is R/W0; the user can only change the protection bit from a 1 to a 0 (and may NOT change a 0 to a 1). The changes are not permanent until the register is committed (saved), at which point the bit change is permanent. If a bit is changed from a 1 to a 0 and not committed, it may be restored by executing a power-on reset sequence. The reset value shown only applies to power-on reset; any other type of reset does not affect this register. Once committed, the only way to restore the factory default value of this register is to perform the sequence detailed in “Recovering a "Locked" Microcontroller” on page 183. If the Flash memory size on the device is less than 64 KB, this register usually reads as zeroes, but software should not rely on these bits to be zero. For additional information, see “Flash Memory Protection” on page 324. Flash Memory Protection Read Enable 1 (FMPRE1) Base 0x400F.E000 Offset 0x204 Type R/W, reset 0xFFFF.FFFF 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 READ_ENABLE Type Reset R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 15 14 13 12 11 10 9 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 8 7 6 5 4 3 2 1 0 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 READ_ENABLE Type Reset R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 Bit/Field Name Type 31:0 READ_ENABLE R/W R/W 1 Reset R/W 1 R/W 1 Description 0xFFFFFFFF Flash Read Enable Configures 2-KB flash blocks to be read or executed only. The policies may be combined as shown in Table 7-1 on page 324. Value Description 0xFFFFFFFF Bits [31:0] each enable protection on a 2-KB block of Flash memory in memory range from 65 to 128 KB. 352 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 20: Flash Memory Protection Read Enable 2 (FMPRE2), offset 0x208 Note: Offset is relative to System Control base address of 0x400FE000. This register stores the read-only protection bits for each 2-KB flash block (FMPPEn stores the execute-only bits). Flash memory up to a total of 64 KB is controlled by this register. Other FMPREn registers (if any) provide protection for other 64K blocks. This register is loaded during the power-on reset sequence. The factory settings for the FMPREn and FMPPEn registers are a value of 1 for all implemented banks. This achieves a policy of open access and programmability. The register bits may be changed by writing the specific register bit. However, this register is R/W0; the user can only change the protection bit from a 1 to a 0 (and may NOT change a 0 to a 1). The changes are not permanent until the register is committed (saved), at which point the bit change is permanent. If a bit is changed from a 1 to a 0 and not committed, it may be restored by executing a power-on reset sequence. The reset value shown only applies to power-on reset; any other type of reset does not affect this register. Once committed, the only way to restore the factory default value of this register is to perform the sequence detailed in “Recovering a "Locked" Microcontroller” on page 183. If the Flash memory size on the device is less than 128 KB, this register usually reads as zeroes, but software should not rely on these bits to be zero. For additional information, see “Flash Memory Protection” on page 324. Flash Memory Protection Read Enable 2 (FMPRE2) Base 0x400F.E000 Offset 0x208 Type R/W, reset 0xFFFF.FFFF 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 READ_ENABLE Type Reset R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 15 14 13 12 11 10 9 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 8 7 6 5 4 3 2 1 0 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 READ_ENABLE Type Reset R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 Bit/Field Name Type 31:0 READ_ENABLE R/W R/W 1 Reset R/W 1 R/W 1 Description 0xFFFFFFFF Flash Read Enable Configures 2-KB flash blocks to be read or executed only. The policies may be combined as shown in Table 7-1 on page 324. Value Description 0xFFFFFFFF Bits [31:0] each enable protection on a 2-KB block of Flash memory in the range from 129 to 192 KB. July 03, 2014 353 Texas Instruments-Production Data Internal Memory Register 21: Flash Memory Protection Read Enable 3 (FMPRE3), offset 0x20C Note: Offset is relative to System Control base address of 0x400FE000. This register stores the read-only protection bits for each 2-KB flash block (FMPPEn stores the execute-only bits). Flash memory up to a total of 64 KB is controlled by this register. Other FMPREn registers (if any) provide protection for other 64K blocks. This register is loaded during the power-on reset sequence. The factory settings for the FMPREn and FMPPEn registers are a value of 1 for all implemented banks. This achieves a policy of open access and programmability. The register bits may be changed by writing the specific register bit. However, this register is R/W0; the user can only change the protection bit from a 1 to a 0 (and may NOT change a 0 to a 1). The changes are not permanent until the register is committed (saved), at which point the bit change is permanent. If a bit is changed from a 1 to a 0 and not committed, it may be restored by executing a power-on reset sequence. The reset value shown only applies to power-on reset; any other type of reset does not affect this register. Once committed, the only way to restore the factory default value of this register is to perform the sequence detailed in “Recovering a "Locked" Microcontroller” on page 183. If the Flash memory size on the device is less than 192 KB, this register usually reads as zeroes, but software should not rely on these bits to be zero. For additional information, see “Flash Memory Protection” on page 324. Flash Memory Protection Read Enable 3 (FMPRE3) Base 0x400F.E000 Offset 0x20C Type R/W, reset 0xFFFF.FFFF 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 READ_ENABLE Type Reset R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 15 14 13 12 11 10 9 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 8 7 6 5 4 3 2 1 0 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 READ_ENABLE Type Reset R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 Bit/Field Name Type 31:0 READ_ENABLE R/W R/W 1 Reset R/W 1 R/W 1 Description 0xFFFFFFFF Flash Read Enable Configures 2-KB flash blocks to be read or executed only. The policies may be combined as shown in Table 7-1 on page 324. Value Description 0xFFFFFFFF Bits [31:0] each enable protection on a 2-KB block of Flash memory in the range from 193 to 256 KB. 354 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 22: Flash Memory Protection Read Enable 4 (FMPRE4), offset 0x210 Note: Offset is relative to System Control base address of 0x400FE000. This register stores the read-only protection bits for each 2-KB flash block (FMPPEn stores the execute-only bits). Flash memory up to a total of 64 KB is controlled by this register. Other FMPREn registers (if any) provide protection for other 64K blocks. This register is loaded during the power-on reset sequence. The factory settings for the FMPREn and FMPPEn registers are a value of 1 for all implemented banks. This achieves a policy of open access and programmability. The register bits may be changed by writing the specific register bit. However, this register is R/W0; the user can only change the protection bit from a 1 to a 0 (and may NOT change a 0 to a 1). The changes are not permanent until the register is committed (saved), at which point the bit change is permanent. If a bit is changed from a 1 to a 0 and not committed, it may be restored by executing a power-on reset sequence. The reset value shown only applies to power-on reset; any other type of reset does not affect this register. Once committed, the only way to restore the factory default value of this register is to perform the sequence detailed in “Recovering a "Locked" Microcontroller” on page 183. If the Flash memory size on the device is less than 192 KB, this register usually reads as zeroes, but software should not rely on these bits to be zero. For additional information, see “Flash Memory Protection” on page 324. Flash Memory Protection Read Enable 4 (FMPRE4) Base 0x400F.E000 Offset 0x210 Type R/W, reset 0xFFFF.FFFF 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 READ_ENABLE Type Reset R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 15 14 13 12 11 10 9 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 8 7 6 5 4 3 2 1 0 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 READ_ENABLE Type Reset R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 Bit/Field Name Type 31:0 READ_ENABLE R/W R/W 1 Reset R/W 1 R/W 1 Description 0xFFFFFFFF Flash Read Enable Configures 2-KB flash blocks to be read or executed only. The policies may be combined as shown in Table 7-1 on page 324. Value Description 0xFFFFFFFF Bits [31:0] each enable protection on a 2-KB block of Flash memory in the range from 257 to 320 KB. July 03, 2014 355 Texas Instruments-Production Data Internal Memory Register 23: Flash Memory Protection Read Enable 5 (FMPRE5), offset 0x214 Note: Offset is relative to System Control base address of 0x400FE000. This register stores the read-only protection bits for each 2-KB flash block (FMPPEn stores the execute-only bits). Flash memory up to a total of 64 KB is controlled by this register. Other FMPREn registers (if any) provide protection for other 64K blocks. This register is loaded during the power-on reset sequence. The factory settings for the FMPREn and FMPPEn registers are a value of 1 for all implemented banks. This achieves a policy of open access and programmability. The register bits may be changed by writing the specific register bit. However, this register is R/W0; the user can only change the protection bit from a 1 to a 0 (and may NOT change a 0 to a 1). The changes are not permanent until the register is committed (saved), at which point the bit change is permanent. If a bit is changed from a 1 to a 0 and not committed, it may be restored by executing a power-on reset sequence. The reset value shown only applies to power-on reset; any other type of reset does not affect this register. Once committed, the only way to restore the factory default value of this register is to perform the sequence detailed in “Recovering a "Locked" Microcontroller” on page 183. If the Flash memory size on the device is less than 192 KB, this register usually reads as zeroes, but software should not rely on these bits to be zero. For additional information, see “Flash Memory Protection” on page 324. Flash Memory Protection Read Enable 5 (FMPRE5) Base 0x400F.E000 Offset 0x214 Type R/W, reset 0xFFFF.FFFF 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 READ_ENABLE Type Reset R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 15 14 13 12 11 10 9 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 8 7 6 5 4 3 2 1 0 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 READ_ENABLE Type Reset R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 Bit/Field Name Type 31:0 READ_ENABLE R/W R/W 1 Reset R/W 1 R/W 1 Description 0xFFFFFFFF Flash Read Enable Configures 2-KB flash blocks to be read or executed only. The policies may be combined as shown in Table 7-1 on page 324. Value Description 0xFFFFFFFF Bits [31:0] each enable protection on a 2-KB block of Flash memory in the range from 321 to 384 KB. 356 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 24: Flash Memory Protection Read Enable 6 (FMPRE6), offset 0x218 Note: Offset is relative to System Control base address of 0x400FE000. This register stores the read-only protection bits for each 2-KB flash block (FMPPEn stores the execute-only bits). Flash memory up to a total of 64 KB is controlled by this register. Other FMPREn registers (if any) provide protection for other 64K blocks. This register is loaded during the power-on reset sequence. The factory settings for the FMPREn and FMPPEn registers are a value of 1 for all implemented banks. This achieves a policy of open access and programmability. The register bits may be changed by writing the specific register bit. However, this register is R/W0; the user can only change the protection bit from a 1 to a 0 (and may NOT change a 0 to a 1). The changes are not permanent until the register is committed (saved), at which point the bit change is permanent. If a bit is changed from a 1 to a 0 and not committed, it may be restored by executing a power-on reset sequence. The reset value shown only applies to power-on reset; any other type of reset does not affect this register. Once committed, the only way to restore the factory default value of this register is to perform the sequence detailed in “Recovering a "Locked" Microcontroller” on page 183. If the Flash memory size on the device is less than 192 KB, this register usually reads as zeroes, but software should not rely on these bits to be zero. For additional information, see “Flash Memory Protection” on page 324. Flash Memory Protection Read Enable 6 (FMPRE6) Base 0x400F.E000 Offset 0x218 Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 READ_ENABLE Type Reset R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 15 14 13 12 11 10 9 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 8 7 6 5 4 3 2 1 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 READ_ENABLE Type Reset R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 Bit/Field Name Type 31:0 READ_ENABLE R/W R/W 0 Reset R/W 0 R/W 0 Description 0x00000000 Flash Read Enable Configures 2-KB flash blocks to be read or executed only. The policies may be combined as shown in Table 7-1 on page 324. Value Description 0x00000000 Bits [31:0] each enable protection on a 2-KB block of Flash memory in the range from 385 to 448 KB. July 03, 2014 357 Texas Instruments-Production Data Internal Memory Register 25: Flash Memory Protection Read Enable 7 (FMPRE7), offset 0x21C Note: Offset is relative to System Control base address of 0x400FE000. This register stores the read-only protection bits for each 2-KB flash block (FMPPEn stores the execute-only bits). Flash memory up to a total of 64 KB is controlled by this register. Other FMPREn registers (if any) provide protection for other 64K blocks. This register is loaded during the power-on reset sequence. The factory settings for the FMPREn and FMPPEn registers are a value of 1 for all implemented banks. This achieves a policy of open access and programmability. The register bits may be changed by writing the specific register bit. However, this register is R/W0; the user can only change the protection bit from a 1 to a 0 (and may NOT change a 0 to a 1). The changes are not permanent until the register is committed (saved), at which point the bit change is permanent. If a bit is changed from a 1 to a 0 and not committed, it may be restored by executing a power-on reset sequence. The reset value shown only applies to power-on reset; any other type of reset does not affect this register. Once committed, the only way to restore the factory default value of this register is to perform the sequence detailed in “Recovering a "Locked" Microcontroller” on page 183. If the Flash memory size on the device is less than 192 KB, this register usually reads as zeroes, but software should not rely on these bits to be zero. For additional information, see “Flash Memory Protection” on page 324. Flash Memory Protection Read Enable 7 (FMPRE7) Base 0x400F.E000 Offset 0x21C Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 READ_ENABLE Type Reset R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 15 14 13 12 11 10 9 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 8 7 6 5 4 3 2 1 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 READ_ENABLE Type Reset R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 Bit/Field Name Type 31:0 READ_ENABLE R/W R/W 0 Reset R/W 0 R/W 0 Description 0x00000000 Flash Read Enable Configures 2-KB flash blocks to be read or executed only. The policies may be combined as shown in Table 7-1 on page 324. Value Description 0x00000000 Bits [31:0] each enable protection on a 2-KB block of Flash memory in the range from 449 to 512 KB. 358 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 26: Flash Memory Protection Program Enable 1 (FMPPE1), offset 0x404 Note: Offset is relative to System Control base address of 0x400FE000. This register stores the execute-only protection bits for each 2-KB flash block (FMPREn stores the execute-only bits). Flash memory up to a total of 64 KB is controlled by this register. Other FMPPEn registers (if any) provide protection for other 64K blocks. This register is loaded during the power-on reset sequence. The factory settings for the FMPREn and FMPPEn registers are a value of 1 for all implemented banks. This achieves a policy of open access and programmability. The register bits may be changed by writing the specific register bit. However, this register is R/W0; the user can only change the protection bit from a 1 to a 0 (and may NOT change a 0 to a 1). The changes are not permanent until the register is committed (saved), at which point the bit change is permanent. If a bit is changed from a 1 to a 0 and not committed, it may be restored by executing a power-on reset sequence. The reset value shown only applies to power-on reset; any other type of reset does not affect this register. Once committed, the only way to restore the factory default value of this register is to perform the sequence detailed in “Recovering a "Locked" Microcontroller” on page 183. If the Flash memory size on the device is less than 64 KB, this register usually reads as zeroes, but software should not rely on these bits to be zero. For additional information, see “Flash Memory Protection” on page 324. Flash Memory Protection Program Enable 1 (FMPPE1) Base 0x400F.E000 Offset 0x404 Type R/W, reset 0xFFFF.FFFF 31 30 29 28 27 26 25 24 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 15 14 13 12 11 10 9 8 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 23 22 21 20 19 18 17 16 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 7 6 5 4 3 2 1 0 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 PROG_ENABLE Type Reset PROG_ENABLE Type Reset Bit/Field Name Type 31:0 PROG_ENABLE R/W Reset R/W 1 R/W 1 Description 0xFFFFFFFF Flash Programming Enable Configures 2-KB flash blocks to be execute only. The policies may be combined as shown in Table 7-1 on page 324. Value Description 0xFFFFFFFF Bits [31:0] each enable protection on a 2-KB block of Flash memory in memory range from 65 to 128 KB. July 03, 2014 359 Texas Instruments-Production Data Internal Memory Register 27: Flash Memory Protection Program Enable 2 (FMPPE2), offset 0x408 Note: Offset is relative to System Control base address of 0x400FE000. This register stores the execute-only protection bits for each 2-KB flash block (FMPREn stores the execute-only bits). Flash memory up to a total of 64 KB is controlled by this register. Other FMPPEn registers (if any) provide protection for other 64K blocks. This register is loaded during the power-on reset sequence. The factory settings for the FMPREn and FMPPEn registers are a value of 1 for all implemented banks. This achieves a policy of open access and programmability. The register bits may be changed by writing the specific register bit. However, this register is R/W0; the user can only change the protection bit from a 1 to a 0 (and may NOT change a 0 to a 1). The changes are not permanent until the register is committed (saved), at which point the bit change is permanent. If a bit is changed from a 1 to a 0 and not committed, it may be restored by executing a power-on reset sequence. The reset value shown only applies to power-on reset; any other type of reset does not affect this register. Once committed, the only way to restore the factory default value of this register is to perform the sequence detailed in “Recovering a "Locked" Microcontroller” on page 183. If the Flash memory size on the device is less than 128 KB, this register usually reads as zeroes, but software should not rely on these bits to be zero. For additional information, see “Flash Memory Protection” on page 324. Flash Memory Protection Program Enable 2 (FMPPE2) Base 0x400F.E000 Offset 0x408 Type R/W, reset 0xFFFF.FFFF 31 30 29 28 27 26 25 24 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 15 14 13 12 11 10 9 8 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 23 22 21 20 19 18 17 16 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 7 6 5 4 3 2 1 0 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 PROG_ENABLE Type Reset PROG_ENABLE Type Reset Bit/Field Name Type 31:0 PROG_ENABLE R/W Reset R/W 1 R/W 1 Description 0xFFFFFFFF Flash Programming Enable Configures 2-KB flash blocks to be execute only. The policies may be combined as shown in Table 7-1 on page 324. Value Description 0xFFFFFFFF Bits [31:0] each enable protection on a 2-KB block of Flash memory in the range from 129 to 192 KB. 360 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 28: Flash Memory Protection Program Enable 3 (FMPPE3), offset 0x40C Note: Offset is relative to System Control base address of 0x400FE000. This register stores the execute-only protection bits for each 2-KB flash block (FMPREn stores the execute-only bits). Flash memory up to a total of 64 KB is controlled by this register. Other FMPPEn registers (if any) provide protection for other 64K blocks. This register is loaded during the power-on reset sequence. The factory settings for the FMPREn and FMPPEn registers are a value of 1 for all implemented banks. This achieves a policy of open access and programmability. The register bits may be changed by writing the specific register bit. However, this register is R/W0; the user can only change the protection bit from a 1 to a 0 (and may NOT change a 0 to a 1). The changes are not permanent until the register is committed (saved), at which point the bit change is permanent. If a bit is changed from a 1 to a 0 and not committed, it may be restored by executing a power-on reset sequence. The reset value shown only applies to power-on reset; any other type of reset does not affect this register. Once committed, the only way to restore the factory default value of this register is to perform the sequence detailed in “Recovering a "Locked" Microcontroller” on page 183. If the Flash memory size on the device is less than 192 KB, this register usually reads as zeroes, but software should not rely on these bits to be zero. For additional information, see “Flash Memory Protection” on page 324. Flash Memory Protection Program Enable 3 (FMPPE3) Base 0x400F.E000 Offset 0x40C Type R/W, reset 0xFFFF.FFFF 31 30 29 28 27 26 25 24 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 15 14 13 12 11 10 9 8 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 23 22 21 20 19 18 17 16 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 7 6 5 4 3 2 1 0 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 PROG_ENABLE Type Reset PROG_ENABLE Type Reset Bit/Field Name Type 31:0 PROG_ENABLE R/W Reset R/W 1 R/W 1 Description 0xFFFFFFFF Flash Programming Enable Configures 2-KB flash blocks to be execute only. The policies may be combined as shown in Table 7-1 on page 324. Value Description 0xFFFFFFFF Bits [31:0] each enable protection on a 2-KB block of Flash memory in the range from 193 to 256 KB. July 03, 2014 361 Texas Instruments-Production Data Internal Memory Register 29: Flash Memory Protection Program Enable 4 (FMPPE4), offset 0x410 Note: Offset is relative to System Control base address of 0x400FE000. This register stores the execute-only protection bits for each 2-KB flash block (FMPREn stores the execute-only bits). Flash memory up to a total of 64 KB is controlled by this register. Other FMPPEn registers (if any) provide protection for other 64K blocks. This register is loaded during the power-on reset sequence. The factory settings for the FMPREn and FMPPEn registers are a value of 1 for all implemented banks. This achieves a policy of open access and programmability. The register bits may be changed by writing the specific register bit. However, this register is R/W0; the user can only change the protection bit from a 1 to a 0 (and may NOT change a 0 to a 1). The changes are not permanent until the register is committed (saved), at which point the bit change is permanent. If a bit is changed from a 1 to a 0 and not committed, it may be restored by executing a power-on reset sequence. The reset value shown only applies to power-on reset; any other type of reset does not affect this register. Once committed, the only way to restore the factory default value of this register is to perform the sequence detailed in “Recovering a "Locked" Microcontroller” on page 183. If the Flash memory size on the device is less than 192 KB, this register usually reads as zeroes, but software should not rely on these bits to be zero. For additional information, see “Flash Memory Protection” on page 324. Flash Memory Protection Program Enable 4 (FMPPE4) Base 0x400F.E000 Offset 0x410 Type R/W, reset 0xFFFF.FFFF 31 30 29 28 27 26 25 24 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 15 14 13 12 11 10 9 8 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 23 22 21 20 19 18 17 16 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 7 6 5 4 3 2 1 0 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 PROG_ENABLE Type Reset PROG_ENABLE Type Reset Bit/Field Name Type 31:0 PROG_ENABLE R/W Reset R/W 1 R/W 1 Description 0xFFFFFFFF Flash Programming Enable Configures 2-KB flash blocks to be execute only. The policies may be combined as shown in Table 7-1 on page 324. Value Description 0xFFFFFFFF Bits [31:0] each enable protection on a 2-KB block of Flash memory in the range from 257 to 320 KB. 362 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 30: Flash Memory Protection Program Enable 5 (FMPPE5), offset 0x414 Note: Offset is relative to System Control base address of 0x400FE000. This register stores the execute-only protection bits for each 2-KB flash block (FMPREn stores the execute-only bits). Flash memory up to a total of 64 KB is controlled by this register. Other FMPPEn registers (if any) provide protection for other 64K blocks. This register is loaded during the power-on reset sequence. The factory settings for the FMPREn and FMPPEn registers are a value of 1 for all implemented banks. This achieves a policy of open access and programmability. The register bits may be changed by writing the specific register bit. However, this register is R/W0; the user can only change the protection bit from a 1 to a 0 (and may NOT change a 0 to a 1). The changes are not permanent until the register is committed (saved), at which point the bit change is permanent. If a bit is changed from a 1 to a 0 and not committed, it may be restored by executing a power-on reset sequence. The reset value shown only applies to power-on reset; any other type of reset does not affect this register. Once committed, the only way to restore the factory default value of this register is to perform the sequence detailed in “Recovering a "Locked" Microcontroller” on page 183. If the Flash memory size on the device is less than 192 KB, this register usually reads as zeroes, but software should not rely on these bits to be zero. For additional information, see “Flash Memory Protection” on page 324. Flash Memory Protection Program Enable 5 (FMPPE5) Base 0x400F.E000 Offset 0x414 Type R/W, reset 0xFFFF.FFFF 31 30 29 28 27 26 25 24 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 15 14 13 12 11 10 9 8 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 23 22 21 20 19 18 17 16 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 7 6 5 4 3 2 1 0 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 PROG_ENABLE Type Reset PROG_ENABLE Type Reset Bit/Field Name Type 31:0 PROG_ENABLE R/W Reset R/W 1 R/W 1 Description 0xFFFFFFFF Flash Programming Enable Configures 2-KB flash blocks to be execute only. The policies may be combined as shown in Table 7-1 on page 324. Value Description 0xFFFFFFFF Bits [31:0] each enable protection on a 2-KB block of Flash memory in the range from 321 to 384 KB. July 03, 2014 363 Texas Instruments-Production Data Internal Memory Register 31: Flash Memory Protection Program Enable 6 (FMPPE6), offset 0x418 Note: Offset is relative to System Control base address of 0x400FE000. This register stores the execute-only protection bits for each 2-KB flash block (FMPREn stores the execute-only bits). Flash memory up to a total of 64 KB is controlled by this register. Other FMPPEn registers (if any) provide protection for other 64K blocks. This register is loaded during the power-on reset sequence. The factory settings for the FMPREn and FMPPEn registers are a value of 1 for all implemented banks. This achieves a policy of open access and programmability. The register bits may be changed by writing the specific register bit. However, this register is R/W0; the user can only change the protection bit from a 1 to a 0 (and may NOT change a 0 to a 1). The changes are not permanent until the register is committed (saved), at which point the bit change is permanent. If a bit is changed from a 1 to a 0 and not committed, it may be restored by executing a power-on reset sequence. The reset value shown only applies to power-on reset; any other type of reset does not affect this register. Once committed, the only way to restore the factory default value of this register is to perform the sequence detailed in “Recovering a "Locked" Microcontroller” on page 183. If the Flash memory size on the device is less than 192 KB, this register usually reads as zeroes, but software should not rely on these bits to be zero. For additional information, see “Flash Memory Protection” on page 324. Flash Memory Protection Program Enable 6 (FMPPE6) Base 0x400F.E000 Offset 0x418 Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 15 14 13 12 11 10 9 8 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 23 22 21 20 19 18 17 16 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 7 6 5 4 3 2 1 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 PROG_ENABLE Type Reset PROG_ENABLE Type Reset Bit/Field Name Type 31:0 PROG_ENABLE R/W Reset R/W 0 R/W 0 Description 0x00000000 Flash Programming Enable Configures 2-KB flash blocks to be execute only. The policies may be combined as shown in Table 7-1 on page 324. Value Description 0x00000000 Bits [31:0] each enable protection on a 2-KB block of Flash memory in the range from 385 to 448 KB. 364 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 32: Flash Memory Protection Program Enable 7 (FMPPE7), offset 0x41C Note: Offset is relative to System Control base address of 0x400FE000. This register stores the execute-only protection bits for each 2-KB flash block (FMPREn stores the execute-only bits). Flash memory up to a total of 64 KB is controlled by this register. Other FMPPEn registers (if any) provide protection for other 64K blocks. This register is loaded during the power-on reset sequence. The factory settings for the FMPREn and FMPPEn registers are a value of 1 for all implemented banks. This achieves a policy of open access and programmability. The register bits may be changed by writing the specific register bit. However, this register is R/W0; the user can only change the protection bit from a 1 to a 0 (and may NOT change a 0 to a 1). The changes are not permanent until the register is committed (saved), at which point the bit change is permanent. If a bit is changed from a 1 to a 0 and not committed, it may be restored by executing a power-on reset sequence. The reset value shown only applies to power-on reset; any other type of reset does not affect this register. Once committed, the only way to restore the factory default value of this register is to perform the sequence detailed in “Recovering a "Locked" Microcontroller” on page 183. If the Flash memory size on the device is less than 192 KB, this register usually reads as zeroes, but software should not rely on these bits to be zero. For additional information, see “Flash Memory Protection” on page 324. Flash Memory Protection Program Enable 7 (FMPPE7) Base 0x400F.E000 Offset 0x41C Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 15 14 13 12 11 10 9 8 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 23 22 21 20 19 18 17 16 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 7 6 5 4 3 2 1 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 PROG_ENABLE Type Reset PROG_ENABLE Type Reset Bit/Field Name Type 31:0 PROG_ENABLE R/W Reset R/W 0 R/W 0 Description 0x00000000 Flash Programming Enable Configures 2-KB flash blocks to be execute only. The policies may be combined as shown in Table 7-1 on page 324. Value Description 0x00000000 Bits [31:0] each enable protection on a 2-KB block of Flash memory in the range from 449 to 512 KB. July 03, 2014 365 Texas Instruments-Production Data Micro Direct Memory Access (μDMA) 8 Micro Direct Memory Access (μDMA) The LM3S9U90 microcontroller includes a Direct Memory Access (DMA) controller, known as micro-DMA (μDMA). The μDMA controller provides a way to offload data transfer tasks from the Cortex™-M3 processor, allowing for more efficient use of the processor and the available bus bandwidth. The μDMA controller can perform transfers between memory and peripherals. It has dedicated channels for each supported on-chip module and can be programmed to automatically perform transfers between peripherals and memory as the peripheral is ready to transfer more data. The μDMA controller provides the following features: ® ® ■ ARM PrimeCell 32-channel configurable µDMA controller ■ Support for memory-to-memory, memory-to-peripheral, and peripheral-to-memory in multiple transfer modes – Basic for simple transfer scenarios – Ping-pong for continuous data flow – Scatter-gather for a programmable list of up to 256 arbitrary transfers initiated from a single request ■ Highly flexible and configurable channel operation – Independently configured and operated channels – Dedicated channels for supported on-chip modules – Primary and secondary channel assignments – One channel each for receive and transmit path for bidirectional modules – Dedicated channel for software-initiated transfers – Per-channel configurable priority scheme – Optional software-initiated requests for any channel ■ Two levels of priority ■ Design optimizations for improved bus access performance between µDMA controller and the processor core – µDMA controller access is subordinate to core access – RAM striping – Peripheral bus segmentation ■ Data sizes of 8, 16, and 32 bits ■ Transfer size is programmable in binary steps from 1 to 1024 ■ Source and destination address increment size of byte, half-word, word, or no increment 366 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller ■ Maskable peripheral requests ■ Interrupt on transfer completion, with a separate interrupt per channel 8.1 Block Diagram Figure 8-1. μDMA Block Diagram uDMA Controller DMA error System Memory CH Control Table Peripheral DMA Channel 0 • • • Peripheral DMA Channel N-1 Nested Vectored Interrupt Controller (NVIC) IRQ General Peripheral N Registers request done request done request done DMASTAT DMACFG DMACTLBASE DMAALTBASE DMAWAITSTAT DMASWREQ DMAUSEBURSTSET DMAUSEBURSTCLR DMAREQMASKSET DMAREQMASKCLR DMAENASET DMAENACLR DMAALTSET DMAALTCLR DMAPRIOSET DMAPRIOCLR DMAERRCLR DMACHASGN DMACHIS DMASRCENDP DMADSTENDP DMACHCTRL • • • DMASRCENDP DMADSTENDP DMACHCTRL Transfer Buffers Used by µDMA ARM Cortex-M3 8.2 Functional Description The μDMA controller is a flexible and highly configurable DMA controller designed to work efficiently with the microcontroller's Cortex-M3 processor core. It supports multiple data sizes and address increment schemes, multiple levels of priority among DMA channels, and several transfer modes to allow for sophisticated programmed data transfers. The μDMA controller's usage of the bus is always subordinate to the processor core, so it never holds up a bus transaction by the processor. Because the μDMA controller is only using otherwise-idle bus cycles, the data transfer bandwidth it provides is essentially free, with no impact on the rest of the system. The bus architecture has been optimized to greatly enhance the ability of the processor core and the μDMA controller to efficiently share the on-chip bus, thus improving performance. The optimizations include RAM striping and peripheral bus segmentation, which in many cases allow both the processor core and the μDMA controller to access the bus and perform simultaneous data transfers. The μDMA controller can transfer data to and from the on-chip SRAM. However, because the Flash memory and ROM are located on a separate internal bus, it is not possible to transfer data from the Flash memory or ROM with the μDMA controller. Each peripheral function that is supported has a dedicated channel on the μDMA controller that can be configured independently. The μDMA controller implements a unique configuration method using channel control structures that are maintained in system memory by the processor. While simple transfer modes are supported, it is also possible to build up sophisticated "task" lists in memory that allow the μDMA controller to perform arbitrary-sized transfers to and from arbitrary locations as part of a single transfer request. The μDMA controller also supports the use of ping-pong buffering to accommodate constant streaming of data to or from a peripheral. July 03, 2014 367 Texas Instruments-Production Data Micro Direct Memory Access (μDMA) Each channel also has a configurable arbitration size. The arbitration size is the number of items that are transferred in a burst before the μDMA controller rearbitrates for channel priority. Using the arbitration size, it is possible to control exactly how many items are transferred to or from a peripheral each time it makes a μDMA service request. 8.2.1 Channel Assignments μDMA channels 0-31 are assigned to peripherals according to the following table. The DMA Channel Assignment (DMACHASGN) register (see page 416) can be used to specify the primary or secondary assignment. If the primary function is not available on this microcontroller, the secondary function becomes the primary function. If the secondary function is not available, the primary function is the only option. Note: Channels noted in the table as "Available for software" may be assigned to peripherals in the future. However, they are currently available for software use. Channel 30 is dedicated for software use. The USB endpoints mapped to μDMA channels 0-3 can be changed with the USBDMASEL register (see page 1137). Because of the way the μDMA controller interacts with peripherals, the μDMA channel for the peripheral must be enabled in order for the μDMA controller to be able to read and write the peripheral registers, even if a different μDMA channel is used to perform the μDMA transfer. To minimize confusion and chance of software errors, it is best practice to use a peripheral's μDMA channel for performing all μDMA transfers for that peripheral, even if it is processor-triggered and using AUTO mode, which could be considered a software transfer. Note that if the software channel is used, interrupts occur on the dedicated μDMA interrupt vector. If the peripheral channel is used, then the interrupt occurs on the interrupt vector for the peripheral. Table 8-1. μDMA Channel Assignments μDMA Channel Primary Assignment Secondary Assignment 0 USB Endpoint 1 Receive UART2 Receive 1 USB Endpoint 1 Transmit UART2 Transmit 2 USB Endpoint 2 Receive General-Purpose Timer 3A 3 USB Endpoint 2 Transmit General-Purpose Timer 3B 4 USB Endpoint 3 Receive General-Purpose Timer 2A 5 USB Endpoint 3 Transmit General-Purpose Timer 2B 6 Ethernet Receive General-Purpose Timer 2A 7 Ethernet Transmit General-Purpose Timer 2B 8 UART0 Receive UART1 Receive 9 UART0 Transmit UART1 Transmit 10 SSI0 Receive SSI1 Receive 11 SSI0 Transmit SSI1 Transmit 12 Available for software UART2 Receive 13 Available for software UART2 Transmit 14 ADC0 Sample Sequencer 0 General-Purpose Timer 2A 15 ADC0 Sample Sequencer 1 General-Purpose Timer 2B 16 ADC0 Sample Sequencer 2 Available for software 17 ADC0 Sample Sequencer 3 Available for software 368 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Table 8-1. μDMA Channel Assignments (continued) μDMA Channel 8.2.2 Primary Assignment Secondary Assignment 18 General-Purpose Timer 0A General-Purpose Timer 1A 19 General-Purpose Timer 0B General-Purpose Timer 1B 20 General-Purpose Timer 1A EPI0 NBRFIFO 21 General-Purpose Timer 1B EPI0 WFIFO 22 UART1 Receive Available for software 23 UART1 Transmit Available for software 24 SSI1 Receive ADC1 Sample Sequencer 0 25 SSI1 Transmit ADC1 Sample Sequencer 1 26 Available for software ADC1 Sample Sequencer 2 27 Available for software ADC1 Sample Sequencer 3 28 I2S0 Receive Available for software 29 I2S0 Available for software 30 Dedicated for software use 31 Reserved Transmit Priority The μDMA controller assigns priority to each channel based on the channel number and the priority level bit for the channel. Channel number 0 has the highest priority and as the channel number increases, the priority of a channel decreases. Each channel has a priority level bit to provide two levels of priority: default priority and high priority. If the priority level bit is set, then that channel has higher priority than all other channels at default priority. If multiple channels are set for high priority, then the channel number is used to determine relative priority among all the high priority channels. The priority bit for a channel can be set using the DMA Channel Priority Set (DMAPRIOSET) register and cleared with the DMA Channel Priority Clear (DMAPRIOCLR) register. 8.2.3 Arbitration Size When a μDMA channel requests a transfer, the μDMA controller arbitrates among all the channels making a request and services the μDMA channel with the highest priority. Once a transfer begins, it continues for a selectable number of transfers before rearbitrating among the requesting channels again. The arbitration size can be configured for each channel, ranging from 1 to 1024 item transfers. After the μDMA controller transfers the number of items specified by the arbitration size, it then checks among all the channels making a request and services the channel with the highest priority. If a lower priority μDMA channel uses a large arbitration size, the latency for higher priority channels is increased because the μDMA controller completes the lower priority burst before checking for higher priority requests. Therefore, lower priority channels should not use a large arbitration size for best response on high priority channels. The arbitration size can also be thought of as a burst size. It is the maximum number of items that are transferred at any one time in a burst. Here, the term arbitration refers to determination of μDMA channel priority, not arbitration for the bus. When the μDMA controller arbitrates for the bus, the processor always takes priority. Furthermore, the μDMA controller is held off whenever the processor must perform a bus transaction on the same bus, even in the middle of a burst transfer. July 03, 2014 369 Texas Instruments-Production Data Micro Direct Memory Access (μDMA) 8.2.4 Request Types The μDMA controller responds to two types of requests from a peripheral: single or burst. Each peripheral may support either or both types of requests. A single request means that the peripheral is ready to transfer one item, while a burst request means that the peripheral is ready to transfer multiple items. The μDMA controller responds differently depending on whether the peripheral is making a single request or a burst request. If both are asserted, and the μDMA channel has been set up for a burst transfer, then the burst request takes precedence. See Table 8-2 on page 370, which shows how each peripheral supports the two request types. Table 8-2. Request Type Support 8.2.4.1 Peripheral Single Request Signal Burst Request Signal ADC None Sequencer IE bit EPI WFIFO None WFIFO Level (configurable) EPI NBRFIFO None NBRFIFO Level (configurable) Ethernet TX TX FIFO empty None Ethernet RX RX packet received None General-Purpose Timer None Trigger event I2S TX None FIFO service request I2S RX None FIFO service request SSI TX TX FIFO Not Full TX FIFO Level (fixed at 4) SSI RX RX FIFO Not Empty RX FIFO Level (fixed at 4) UART TX TX FIFO Not Full TX FIFO Level (configurable) UART RX RX FIFO Not Empty RX FIFO Level (configurable) USB TX None FIFO TXRDY USB RX None FIFO RXRDY Single Request When a single request is detected, and not a burst request, the μDMA controller transfers one item and then stops to wait for another request. 8.2.4.2 Burst Request When a burst request is detected, the μDMA controller transfers the number of items that is the lesser of the arbitration size or the number of items remaining in the transfer. Therefore, the arbitration size should be the same as the number of data items that the peripheral can accommodate when making a burst request. For example, the UART generates a burst request based on the FIFO trigger level. In this case, the arbitration size should be set to the amount of data that the FIFO can transfer when the trigger level is reached. A burst transfer runs to completion once it is started, and cannot be interrupted, even by a higher priority channel. Burst transfers complete in a shorter time than the same number of non-burst transfers. It may be desirable to use only burst transfers and not allow single transfers. For example, perhaps the nature of the data is such that it only makes sense when transferred together as a single unit rather than one piece at a time. The single request can be disabled by using the DMA Channel Useburst Set (DMAUSEBURSTSET) register. By setting the bit for a channel in this register, the μDMA controller only responds to burst requests for that channel. 370 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller 8.2.5 Channel Configuration The μDMA controller uses an area of system memory to store a set of channel control structures in a table. The control table may have one or two entries for each μDMA channel. Each entry in the table structure contains source and destination pointers, transfer size, and transfer mode. The control table can be located anywhere in system memory, but it must be contiguous and aligned on a 1024-byte boundary. Table 8-3 on page 371 shows the layout in memory of the channel control table. Each channel may have one or two control structures in the control table: a primary control structure and an optional alternate control structure. The table is organized so that all of the primary entries are in the first half of the table, and all the alternate structures are in the second half of the table. The primary entry is used for simple transfer modes where transfers can be reconfigured and restarted after each transfer is complete. In this case, the alternate control structures are not used and therefore only the first half of the table must be allocated in memory; the second half of the control table is not necessary, and that memory can be used for something else. If a more complex transfer mode is used such as ping-pong or scatter-gather, then the alternate control structure is also used and memory space should be allocated for the entire table. Any unused memory in the control table may be used by the application. This includes the control structures for any channels that are unused by the application as well as the unused control word for each channel. Table 8-3. Control Structure Memory Map Offset Channel 0x0 0, Primary 0x10 1, Primary ... ... 0x1F0 31, Primary 0x200 0, Alternate 0x210 1, Alternate ... 0x3F0 ... 31, Alternate Table 8-4 shows an individual control structure entry in the control table. Each entry is aligned on a 16-byte boundary. The entry contains four long words: the source end pointer, the destination end pointer, the control word, and an unused entry. The end pointers point to the ending address of the transfer and are inclusive. If the source or destination is non-incrementing (as for a peripheral register), then the pointer should point to the transfer address. Table 8-4. Channel Control Structure Offset Description 0x000 Source End Pointer 0x004 Destination End Pointer 0x008 Control Word 0x00C Unused The control word contains the following fields: ■ Source and destination data sizes July 03, 2014 371 Texas Instruments-Production Data Micro Direct Memory Access (μDMA) ■ Source and destination address increment size ■ Number of transfers before bus arbitration ■ Total number of items to transfer ■ Useburst flag ■ Transfer mode The control word and each field are described in detail in “μDMA Channel Control Structure” on page 390. The μDMA controller updates the transfer size and transfer mode fields as the transfer is performed. At the end of a transfer, the transfer size indicates 0, and the transfer mode indicates "stopped." Because the control word is modified by the μDMA controller, it must be reconfigured before each new transfer. The source and destination end pointers are not modified, so they can be left unchanged if the source or destination addresses remain the same. Prior to starting a transfer, a μDMA channel must be enabled by setting the appropriate bit in the DMA Channel Enable Set (DMAENASET) register. A channel can be disabled by setting the channel bit in the DMA Channel Enable Clear (DMAENACLR) register. At the end of a complete μDMA transfer, the controller automatically disables the channel. 8.2.6 Transfer Modes The μDMA controller supports several transfer modes. Two of the modes support simple one-time transfers. Several complex modes support a continuous flow of data. 8.2.6.1 Stop Mode While Stop is not actually a transfer mode, it is a valid value for the mode field of the control word. When the mode field has this value, the μDMA controller does not perform any transfers and disables the channel if it is enabled. At the end of a transfer, the μDMA controller updates the control word to set the mode to Stop. 8.2.6.2 Basic Mode In Basic mode, the μDMA controller performs transfers as long as there are more items to transfer, and a transfer request is present. This mode is used with peripherals that assert a μDMA request signal whenever the peripheral is ready for a data transfer. Basic mode should not be used in any situation where the request is momentary even though the entire transfer should be completed. For example, a software-initiated transfer creates a momentary request, and in Basic mode, only the number of transfers specified by the ARBSIZE field in the DMA Channel Control Word (DMACHCTL) register is transferred on a software request, even if there is more data to transfer. When all of the items have been transferred using Basic mode, the μDMA controller sets the mode for that channel to Stop. 8.2.6.3 Auto Mode Auto mode is similar to Basic mode, except that once a transfer request is received, the transfer runs to completion, even if the μDMA request is removed. This mode is suitable for software-triggered transfers. Generally, Auto mode is not used with a peripheral. When all the items have been transferred using Auto mode, the μDMA controller sets the mode for that channel to Stop. 372 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller 8.2.6.4 Ping-Pong Ping-Pong mode is used to support a continuous data flow to or from a peripheral. To use Ping-Pong mode, both the primary and alternate data structures must be implemented. Both structures are set up by the processor for data transfer between memory and a peripheral. The transfer is started using the primary control structure. When the transfer using the primary control structure is complete, the μDMA controller reads the alternate control structure for that channel to continue the transfer. Each time this happens, an interrupt is generated, and the processor can reload the control structure for the just-completed transfer. Data flow can continue indefinitely this way, using the primary and alternate control structures to switch back and forth between buffers as the data flows to or from the peripheral. Refer to Figure 8-2 on page 374 for an example showing operation in Ping-Pong mode. July 03, 2014 373 Texas Instruments-Production Data Micro Direct Memory Access (μDMA) Figure 8-2. Example of Ping-Pong μDMA Transaction µDMA Controller SOURCE DEST CONTROL Unused transfers using BUFFER A transfer continues using alternate Primary Structure Cortex-M3 Processor SOURCE DEST CONTROL Unused Pe rip he ral /µD M AI nte rru p t transfers using BUFFER B Time SOURCE DEST CONTROL Unused Pe Alternate Structure 8.2.6.5 SOURCE DEST CONTROL Unused rip he ral /µD M AI nte transfers using BUFFER A rru pt BUFFER A · Process data in BUFFER B · Reload alternate structure transfer continues using alternate Primary Structure BUFFER B · Process data in BUFFER A · Reload primary structure transfer continues using primary Alternate Structure BUFFER A Pe rip he ral /µD M AI nte transfers using BUFFER B rru pt BUFFER B · Process data in BUFFER B · Reload alternate structure Memory Scatter-Gather Memory Scatter-Gather mode is a complex mode used when data must be transferred to or from varied locations in memory instead of a set of contiguous locations in a memory buffer. For example, a gather μDMA operation could be used to selectively read the payload of several stored packets of a communication protocol and store them together in sequence in a memory buffer. 374 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller In Memory Scatter-Gather mode, the primary control structure is used to program the alternate control structure from a table in memory. The table is set up by the processor software and contains a list of control structures, each containing the source and destination end pointers, and the control word for a specific transfer. The mode of each control word must be set to Scatter-Gather mode. Each entry in the table is copied in turn to the alternate structure where it is then executed. The μDMA controller alternates between using the primary control structure to copy the next transfer instruction from the list and then executing the new transfer instruction. The end of the list is marked by programming the control word for the last entry to use Auto transfer mode. Once the last transfer is performed using Auto mode, the μDMA controller stops. A completion interrupt is generated only after the last transfer. It is possible to loop the list by having the last entry copy the primary control structure to point back to the beginning of the list (or to a new list). It is also possible to trigger a set of other channels to perform a transfer, either directly, by programming a write to the software trigger for another channel, or indirectly, by causing a peripheral action that results in a μDMA request. By programming the μDMA controller using this method, a set of up to 256 arbitrary transfers can be performed based on a single μDMA request. Refer to Figure 8-3 on page 376 and Figure 8-4 on page 377, which show an example of operation in Memory Scatter-Gather mode. This example shows a gather operation, where data in three separate buffers in memory is copied together into one buffer. Figure 8-3 on page 376 shows how the application sets up a μDMA task list in memory that is used by the controller to perform three sets of copy operations from different locations in memory. The primary control structure for the channel that is used for the operation is configured to copy from the task list to the alternate control structure. Figure 8-4 on page 377 shows the sequence as the μDMA controller performs the three sets of copy operations. First, using the primary control structure, the μDMA controller loads the alternate control structure with task A. It then performs the copy operation specified by task A, copying the data from the source buffer A to the destination buffer. Next, the μDMA controller again uses the primary control structure to load task B into the alternate control structure, and then performs the B operation with the alternate control structure. The process is repeated for task C. July 03, 2014 375 Texas Instruments-Production Data Micro Direct Memory Access (μDMA) Figure 8-3. Memory Scatter-Gather, Setup and Configuration 1 2 3 Source and Destination Buffer in Memory Task List in Memory Channel Control Table in Memory 4 WORDS (SRC A) SRC A DST ITEMS=4 16 WORDS (SRC B) SRC Unused DST SRC ITEMS=12 DST B “TASK” A ITEMS=16 Channel Primary Control Structure “TASK” B Unused SRC DST ITEMS=1 “TASK” C Unused SRC DST Channel Alternate Control Structure ITEMS=n 1 WORD (SRC C) C 4 (DEST A) 16 (DEST B) 1 (DEST C) NOTES: 1. Application has a need to copy data items from three separate locations in memory into one combined buffer. 2. Application sets up µDMA “task list” in memory, which contains the pointers and control configuration for three µDMA copy “tasks.” 3. Application sets up the channel primary control structure to copy each task configuration, one at a time, to the alternate control structure, where it is executed by the µDMA controller. 4. The SRC and DST pointers in the task list must point to the last location in the corresponding buffer. 376 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Figure 8-4. Memory Scatter-Gather, μDMA Copy Sequence Task List in Memory Buffers in Memory µDMA Control Table in Memory SRC A SRC SRC B PRI COPIED DST TASK A TASK B SRC SRC C ALT COPIED DST TASK C DEST A DEST B DEST C Then, using the channel’s alternate control structure, the µDMA controller copies data from the source buffer A to the destination buffer. Using the channel’s primary control structure, the µDMA controller copies task A configuration to the channel’s alternate control structure. Task List in Memory Buffers in Memory µDMA Control Table in Memory SRC A SRC B SRC PRI DST TASK A SRC TASK B TASK C SRC C COPIED ALT COPIED DST DEST A DEST B DEST C Then, using the channel’s alternate control structure, the µDMA controller copies data from the source buffer B to the destination buffer. Using the channel’s primary control structure, the µDMA controller copies task B configuration to the channel’s alternate control structure. Task List in Memory Buffers in Memory µDMA Control Table in Memory SRC A SRC SRC B PRI DST TASK A SRC TASK B TASK C SRC C ALT DST DEST A COPIED COPIED DEST B DEST C Using the channel’s primary control structure, the µDMA controller copies task C configuration to the channel’s alternate control structure. Then, using the channel’s alternate control structure, the µDMA controller copies data from the source buffer C to the destination buffer. July 03, 2014 377 Texas Instruments-Production Data Micro Direct Memory Access (μDMA) 8.2.6.6 Peripheral Scatter-Gather Peripheral Scatter-Gather mode is very similar to Memory Scatter-Gather, except that the transfers are controlled by a peripheral making a μDMA request. Upon detecting a request from the peripheral, the μDMA controller uses the primary control structure to copy one entry from the list to the alternate control structure and then performs the transfer. At the end of this transfer, the next transfer is started only if the peripheral again asserts a μDMA request. The μDMA controller continues to perform transfers from the list only when the peripheral is making a request, until the last transfer is complete. A completion interrupt is generated only after the last transfer. By using this method, the μDMA controller can transfer data to or from a peripheral from a set of arbitrary locations whenever the peripheral is ready to transfer data. Refer to Figure 8-5 on page 379 and Figure 8-6 on page 380, which show an example of operation in Peripheral Scatter-Gather mode. This example shows a gather operation, where data from three separate buffers in memory is copied to a single peripheral data register. Figure 8-5 on page 379 shows how the application sets up a µDMA task list in memory that is used by the controller to perform three sets of copy operations from different locations in memory. The primary control structure for the channel that is used for the operation is configured to copy from the task list to the alternate control structure. Figure 8-6 on page 380 shows the sequence as the µDMA controller performs the three sets of copy operations. First, using the primary control structure, the µDMA controller loads the alternate control structure with task A. It then performs the copy operation specified by task A, copying the data from the source buffer A to the peripheral data register. Next, the µDMA controller again uses the primary control structure to load task B into the alternate control structure, and then performs the B operation with the alternate control structure. The process is repeated for task C. 378 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Figure 8-5. Peripheral Scatter-Gather, Setup and Configuration 1 2 3 Source Buffer in Memory Task List in Memory Channel Control Table in Memory 4 WORDS (SRC A) SRC A DST ITEMS=4 16 WORDS (SRC B) SRC DST SRC ITEMS=12 DST B “TASK” A Unused ITEMS=16 Channel Primary Control Structure “TASK” B Unused SRC DST ITEMS=1 “TASK” C Unused SRC DST Channel Alternate Control Structure ITEMS=n 1 WORD (SRC C) C Peripheral Data Register DEST NOTES: 1. Application has a need to copy data items from three separate locations in memory into a peripheral data register. 2. Application sets up µDMA “task list” in memory, which contains the pointers and control configuration for three µDMA copy “tasks.” 3. Application sets up the channel primary control structure to copy each task configuration, one at a time, to the alternate control structure, where it is executed by the µDMA controller. July 03, 2014 379 Texas Instruments-Production Data Micro Direct Memory Access (μDMA) Figure 8-6. Peripheral Scatter-Gather, μDMA Copy Sequence Task List in Memory Buffers in Memory µDMA Control Table in Memory SRC A SRC SRC B PRI COPIED DST TASK A TASK B SRC SRC C ALT COPIED DST TASK C Then, using the channel’s alternate control structure, the µDMA controller copies data from the source buffer A to the peripheral data register. Using the channel’s primary control structure, the µDMA controller copies task A configuration to the channel’s alternate control structure. Task List in Memory Peripheral Data Register Buffers in Memory µDMA Control Table in Memory SRC A SRC SRC B PRI DST TASK A SRC TASK B TASK C SRC C COPIED ALT COPIED DST Then, using the channel’s alternate control structure, the µDMA controller copies data from the source buffer B to the peripheral data register. Using the channel’s primary control structure, the µDMA controller copies task B configuration to the channel’s alternate control structure. Task List in Memory Peripheral Data Register Buffers in Memory µDMA Control Table in Memory SRC A SRC SRC B PRI DST TASK A SRC TASK B TASK C SRC C ALT DST COPIED COPIED Peripheral Data Register Using the channel’s primary control structure, the µDMA controller copies task C configuration to the channel’s alternate control structure. Then, using the channel’s alternate control structure, the µDMA controller copies data from the source buffer C to the peripheral data register. 380 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller 8.2.7 Transfer Size and Increment The μDMA controller supports transfer data sizes of 8, 16, or 32 bits. The source and destination data size must be the same for any given transfer. The source and destination address can be auto-incremented by bytes, half-words, or words, or can be set to no increment. The source and destination address increment values can be set independently, and it is not necessary for the address increment to match the data size as long as the increment is the same or larger than the data size. For example, it is possible to perform a transfer using 8-bit data size, but using an address increment of full words (4 bytes). The data to be transferred must be aligned in memory according to the data size (8, 16, or 32 bits). Table 8-5 shows the configuration to read from a peripheral that supplies 8-bit data. Table 8-5. μDMA Read Example: 8-Bit Peripheral 8.2.8 Field Configuration Source data size 8 bits Destination data size 8 bits Source address increment No increment Destination address increment Byte Source end pointer Peripheral read FIFO register Destination end pointer End of the data buffer in memory Peripheral Interface Each peripheral that supports μDMA has a single request and/or burst request signal that is asserted when the peripheral is ready to transfer data (see Table 8-2 on page 370). The request signal can be disabled or enabled using the DMA Channel Request Mask Set (DMAREQMASKSET) and DMA Channel Request Mask Clear (DMAREQMASKCLR) registers. The μDMA request signal is disabled, or masked, when the channel request mask bit is set. When the request is not masked, the μDMA channel is configured correctly and enabled, and the peripheral asserts the request signal, the μDMA controller begins the transfer. Note: When using μDMA to transfer data to and from a peripheral, the peripheral must disable all interrupts to the NVIC. When a μDMA transfer is complete, the μDMA controller generates an interrupt, see “Interrupts and Errors” on page 382 for more information. For more information on how a specific peripheral interacts with the μDMA controller, refer to the DMA Operation section in the chapter that discusses that peripheral. 8.2.9 Software Request One μDMA channel is dedicated to software-initiated transfers. This channel also has a dedicated interrupt to signal completion of a μDMA transfer. A transfer is initiated by software by first configuring and enabling the transfer, and then issuing a software request using the DMA Channel Software Request (DMASWREQ) register. For software-based transfers, the Auto transfer mode should be used. It is possible to initiate a transfer on any channel using the DMASWREQ register. If a request is initiated by software using a peripheral μDMA channel, then the completion interrupt occurs on the interrupt vector for the peripheral instead of the software interrupt vector. Any channel may be used for software requests as long as the corresponding peripheral is not using μDMA for data transfer. July 03, 2014 381 Texas Instruments-Production Data Micro Direct Memory Access (μDMA) 8.2.10 Interrupts and Errors When a μDMA transfer is complete, the μDMA controller generates a completion interrupt on the interrupt vector of the peripheral. Therefore, if μDMA is used to transfer data for a peripheral and interrupts are used, then the interrupt handler for that peripheral must be designed to handle the μDMA transfer completion interrupt. If the transfer uses the software μDMA channel, then the completion interrupt occurs on the dedicated software μDMA interrupt vector (see Table 8-6 on page 382). When μDMA is enabled for a peripheral, the μDMA controller stops the normal transfer interrupts for a peripheral from reaching the interrupt controller (the interrupts are still reported in the peripheral's interrupt registers). Thus, when a large amount of data is transferred using μDMA, instead of receiving multiple interrupts from the peripheral as data flows, the interrupt controller receives only one interrupt when the transfer is complete. Unmasked peripheral error interrupts continue to be sent to the interrupt controller. When a μDMA channel generates a completion interrupt, the CHIS bit corresponding to the peripheral channel is set in the DMA Channel Interrupt Status (DMACHIS) register (see page 417). This register can be used by the peripheral interrupt handler code to determine if the interrupt was caused by the μDMA channel or an error event reported by the peripheral's interrupt registers. The completion interrupt request from the μDMA controller is automatically cleared when the interrupt handler is activated. If the μDMA controller encounters a bus or memory protection error as it attempts to perform a data transfer, it disables the μDMA channel that caused the error and generates an interrupt on the μDMA error interrupt vector. The processor can read the DMA Bus Error Clear (DMAERRCLR) register to determine if an error is pending. The ERRCLR bit is set if an error occurred. The error can be cleared by writing a 1 to the ERRCLR bit. Table 8-6 shows the dedicated interrupt assignments for the μDMA controller. Table 8-6. μDMA Interrupt Assignments Interrupt Assignment 46 μDMA Software Channel Transfer 47 μDMA Error 8.3 Initialization and Configuration 8.3.1 Module Initialization Before the μDMA controller can be used, it must be enabled in the System Control block and in the peripheral. The location of the channel control structure must also be programmed. The following steps should be performed one time during system initialization: 1. The μDMA peripheral must be enabled in the System Control block. To do this, set the UDMA bit of the System Control RCGC2 register (see page 277). 2. Enable the μDMA controller by setting the MASTEREN bit of the DMA Configuration (DMACFG) register. 3. Program the location of the channel control table by writing the base address of the table to the DMA Channel Control Base Pointer (DMACTLBASE) register. The base address must be aligned on a 1024-byte boundary. 382 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller 8.3.2 Configuring a Memory-to-Memory Transfer μDMA channel 30 is dedicated for software-initiated transfers. However, any channel can be used for software-initiated, memory-to-memory transfer if the associated peripheral is not being used. 8.3.2.1 Configure the Channel Attributes First, configure the channel attributes: 1. Program bit 30 of the DMA Channel Priority Set (DMAPRIOSET) or DMA Channel Priority Clear (DMAPRIOCLR) registers to set the channel to High priority or Default priority. 2. Set bit 30 of the DMA Channel Primary Alternate Clear (DMAALTCLR) register to select the primary channel control structure for this transfer. 3. Set bit 30 of the DMA Channel Useburst Clear (DMAUSEBURSTCLR) register to allow the μDMA controller to respond to single and burst requests. 4. Set bit 30 of the DMA Channel Request Mask Clear (DMAREQMASKCLR) register to allow the μDMA controller to recognize requests for this channel. 8.3.2.2 Configure the Channel Control Structure Now the channel control structure must be configured. This example transfers 256 words from one memory buffer to another. Channel 30 is used for a software transfer, and the control structure for channel 30 is at offset 0x1E0 of the channel control table. The channel control structure for channel 30 is located at the offsets shown in Table 8-7. Table 8-7. Channel Control Structure Offsets for Channel 30 Offset Description Control Table Base + 0x1E0 Channel 30 Source End Pointer Control Table Base + 0x1E4 Channel 30 Destination End Pointer Control Table Base + 0x1E8 Channel 30 Control Word Configure the Source and Destination The source and destination end pointers must be set to the last address for the transfer (inclusive). 1. Program the source end pointer at offset 0x1E0 to the address of the source buffer + 0x3FC. 2. Program the destination end pointer at offset 0x1E4 to the address of the destination buffer + 0x3FC. The control word at offset 0x1E8 must be programmed according to Table 8-8. Table 8-8. Channel Control Word Configuration for Memory Transfer Example Field in DMACHCTL Bits Value DSTINC 31:30 2 32-bit destination address increment DSTSIZE 29:28 2 32-bit destination data size SRCINC 27:26 2 32-bit source address increment SRCSIZE 25:24 2 32-bit source data size reserved 23:18 0 Reserved July 03, 2014 Description 383 Texas Instruments-Production Data Micro Direct Memory Access (μDMA) Table 8-8. Channel Control Word Configuration for Memory Transfer Example (continued) Field in DMACHCTL Bits Description ARBSIZE 17:14 3 XFERSIZE 13:4 255 3 0 N/A for this transfer type 2:0 2 Use Auto-request transfer mode NXTUSEBURST XFERMODE 8.3.2.3 Value Arbitrates after 8 transfers Transfer 256 items Start the Transfer Now the channel is configured and is ready to start. 1. Enable the channel by setting bit 30 of the DMA Channel Enable Set (DMAENASET) register. 2. Issue a transfer request by setting bit 30 of the DMA Channel Software Request (DMASWREQ) register. The μDMA transfer begins. If the interrupt is enabled, then the processor is notified by interrupt when the transfer is complete. If needed, the status can be checked by reading bit 30 of the DMAENASET register. This bit is automatically cleared when the transfer is complete. The status can also be checked by reading the XFERMODE field of the channel control word at offset 0x1E8. This field is automatically cleared at the end of the transfer. 8.3.3 Configuring a Peripheral for Simple Transmit This example configures the μDMA controller to transmit a buffer of data to a peripheral. The peripheral has a transmit FIFO with a trigger level of 4. The example peripheral uses μDMA channel 7. 8.3.3.1 Configure the Channel Attributes First, configure the channel attributes: 1. Configure bit 7 of the DMA Channel Priority Set (DMAPRIOSET) or DMA Channel Priority Clear (DMAPRIOCLR) registers to set the channel to High priority or Default priority. 2. Set bit 7 of the DMA Channel Primary Alternate Clear (DMAALTCLR) register to select the primary channel control structure for this transfer. 3. Set bit 7 of the DMA Channel Useburst Clear (DMAUSEBURSTCLR) register to allow the μDMA controller to respond to single and burst requests. 4. Set bit 7 of the DMA Channel Request Mask Clear (DMAREQMASKCLR) register to allow the μDMA controller to recognize requests for this channel. 8.3.3.2 Configure the Channel Control Structure This example transfers 64 bytes from a memory buffer to the peripheral's transmit FIFO register using μDMA channel 7. The control structure for channel 7 is at offset 0x070 of the channel control table. The channel control structure for channel 7 is located at the offsets shown in Table 8-9. Table 8-9. Channel Control Structure Offsets for Channel 7 Offset Description Control Table Base + 0x070 Channel 7 Source End Pointer 384 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Table 8-9. Channel Control Structure Offsets for Channel 7 (continued) Offset Description Control Table Base + 0x074 Channel 7 Destination End Pointer Control Table Base + 0x078 Channel 7 Control Word Configure the Source and Destination The source and destination end pointers must be set to the last address for the transfer (inclusive). Because the peripheral pointer does not change, it simply points to the peripheral's data register. 1. Program the source end pointer at offset 0x070 to the address of the source buffer + 0x3F. 2. Program the destination end pointer at offset 0x074 to the address of the peripheral's transmit FIFO register. The control word at offset 0x078 must be programmed according to Table 8-10. Table 8-10. Channel Control Word Configuration for Peripheral Transmit Example Field in DMACHCTL Bits Value DSTINC 31:30 3 Destination address does not increment DSTSIZE 29:28 0 8-bit destination data size SRCINC 27:26 0 8-bit source address increment SRCSIZE 25:24 0 8-bit source data size reserved 23:18 0 Reserved ARBSIZE 17:14 2 Arbitrates after 4 transfers XFERSIZE 13:4 63 Transfer 64 items 3 0 N/A for this transfer type 2:0 1 Use Basic transfer mode NXTUSEBURST XFERMODE Note: 8.3.3.3 Description In this example, it is not important if the peripheral makes a single request or a burst request. Because the peripheral has a FIFO that triggers at a level of 4, the arbitration size is set to 4. If the peripheral does make a burst request, then 4 bytes are transferred, which is what the FIFO can accommodate. If the peripheral makes a single request (if there is any space in the FIFO), then one byte is transferred at a time. If it is important to the application that transfers only be made in bursts, then the Channel Useburst SET[7] bit should be set in the DMA Channel Useburst Set (DMAUSEBURSTSET) register. Start the Transfer Now the channel is configured and is ready to start. 1. Enable the channel by setting bit 7 of the DMA Channel Enable Set (DMAENASET) register. The μDMA controller is now configured for transfer on channel 7. The controller makes transfers to the peripheral whenever the peripheral asserts a μDMA request. The transfers continue until the entire buffer of 64 bytes has been transferred. When that happens, the μDMA controller disables the channel and sets the XFERMODE field of the channel control word to 0 (Stopped). The status of the transfer can be checked by reading bit 7 of the DMA Channel Enable Set (DMAENASET) register. This bit is automatically cleared when the transfer is complete. The status can also be checked by reading the XFERMODE field of the channel control word at offset 0x078. This field is automatically cleared at the end of the transfer. July 03, 2014 385 Texas Instruments-Production Data Micro Direct Memory Access (μDMA) If peripheral interrupts are enabled, then the peripheral interrupt handler receives an interrupt when the entire transfer is complete. 8.3.4 Configuring a Peripheral for Ping-Pong Receive This example configures the μDMA controller to continuously receive 8-bit data from a peripheral into a pair of 64-byte buffers. The peripheral has a receive FIFO with a trigger level of 8. The example peripheral uses μDMA channel 8. 8.3.4.1 Configure the Channel Attributes First, configure the channel attributes: 1. Configure bit 8 of the DMA Channel Priority Set (DMAPRIOSET) or DMA Channel Priority Clear (DMAPRIOCLR) registers to set the channel to High priority or Default priority. 2. Set bit 8 of the DMA Channel Primary Alternate Clear (DMAALTCLR) register to select the primary channel control structure for this transfer. 3. Set bit 8 of the DMA Channel Useburst Clear (DMAUSEBURSTCLR) register to allow the μDMA controller to respond to single and burst requests. 4. Set bit 8 of the DMA Channel Request Mask Clear (DMAREQMASKCLR) register to allow the μDMA controller to recognize requests for this channel. 8.3.4.2 Configure the Channel Control Structure This example transfers bytes from the peripheral's receive FIFO register into two memory buffers of 64 bytes each. As data is received, when one buffer is full, the μDMA controller switches to use the other. To use Ping-Pong buffering, both primary and alternate channel control structures must be used. The primary control structure for channel 8 is at offset 0x080 of the channel control table, and the alternate channel control structure is at offset 0x280. The channel control structures for channel 8 are located at the offsets shown in Table 8-11. Table 8-11. Primary and Alternate Channel Control Structure Offsets for Channel 8 Offset Description Control Table Base + 0x080 Channel 8 Primary Source End Pointer Control Table Base + 0x084 Channel 8 Primary Destination End Pointer Control Table Base + 0x088 Channel 8 Primary Control Word Control Table Base + 0x280 Channel 8 Alternate Source End Pointer Control Table Base + 0x284 Channel 8 Alternate Destination End Pointer Control Table Base + 0x288 Channel 8 Alternate Control Word Configure the Source and Destination The source and destination end pointers must be set to the last address for the transfer (inclusive). Because the peripheral pointer does not change, it simply points to the peripheral's data register. Both the primary and alternate sets of pointers must be configured. 1. Program the primary source end pointer at offset 0x080 to the address of the peripheral's receive buffer. 386 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller 2. Program the primary destination end pointer at offset 0x084 to the address of ping-pong buffer A + 0x3F. 3. Program the alternate source end pointer at offset 0x280 to the address of the peripheral's receive buffer. 4. Program the alternate destination end pointer at offset 0x284 to the address of ping-pong buffer B + 0x3F. The primary control word at offset 0x088 and the alternate control word at offset 0x288 are initially programmed the same way. 1. Program the primary channel control word at offset 0x088 according to Table 8-12. 2. Program the alternate channel control word at offset 0x288 according to Table 8-12. Table 8-12. Channel Control Word Configuration for Peripheral Ping-Pong Receive Example Field in DMACHCTL Bits Value DSTINC 31:30 0 8-bit destination address increment DSTSIZE 29:28 0 8-bit destination data size SRCINC 27:26 3 Source address does not increment SRCSIZE 25:24 0 8-bit source data size reserved 23:18 0 Reserved ARBSIZE 17:14 3 Arbitrates after 8 transfers XFERSIZE 13:4 63 Transfer 64 items 3 0 N/A for this transfer type 2:0 3 Use Ping-Pong transfer mode NXTUSEBURST XFERMODE Note: 8.3.4.3 Description In this example, it is not important if the peripheral makes a single request or a burst request. Because the peripheral has a FIFO that triggers at a level of 8, the arbitration size is set to 8. If the peripheral does make a burst request, then 8 bytes are transferred, which is what the FIFO can accommodate. If the peripheral makes a single request (if there is any data in the FIFO), then one byte is transferred at a time. If it is important to the application that transfers only be made in bursts, then the Channel Useburst SET[8] bit should be set in the DMA Channel Useburst Set (DMAUSEBURSTSET) register. Configure the Peripheral Interrupt An interrupt handler should be configured when using μDMA Ping-Pong mode, it is best to use an interrupt handler. However, the Ping-Pong mode can be configured without interrupts by polling. The interrupt handler is triggered after each buffer is complete. 1. Configure and enable an interrupt handler for the peripheral. 8.3.4.4 Enable the μDMA Channel Now the channel is configured and is ready to start. 1. Enable the channel by setting bit 8 of the DMA Channel Enable Set (DMAENASET) register. July 03, 2014 387 Texas Instruments-Production Data Micro Direct Memory Access (μDMA) 8.3.4.5 Process Interrupts The μDMA controller is now configured and enabled for transfer on channel 8. When the peripheral asserts the μDMA request signal, the μDMA controller makes transfers into buffer A using the primary channel control structure. When the primary transfer to buffer A is complete, it switches to the alternate channel control structure and makes transfers into buffer B. At the same time, the primary channel control word mode field is configured to indicate Stopped, and an interrupt is When an interrupt is triggered, the interrupt handler must determine which buffer is complete and process the data or set a flag that the data must be processed by non-interrupt buffer processing code. Then the next buffer transfer must be set up. In the interrupt handler: 1. Read the primary channel control word at offset 0x088 and check the XFERMODE field. If the field is 0, this means buffer A is complete. If buffer A is complete, then: a. Process the newly received data in buffer A or signal the buffer processing code that buffer A has data available. b. Reprogram the primary channel control word at offset 0x88 according to Table 8-12 on page 387. 2. Read the alternate channel control word at offset 0x288 and check the XFERMODE field. If the field is 0, this means buffer B is complete. If buffer B is complete, then: a. Process the newly received data in buffer B or signal the buffer processing code that buffer B has data available. b. Reprogram the alternate channel control word at offset 0x288 according to Table 8-12 on page 387. 8.3.5 Configuring Channel Assignments Channel assignments for each μDMA channel can be changed using the DMACHASGN register. Each bit represents a μDMA channel. If the bit is set, then the secondary function is used for the channel. Refer to Table 8-1 on page 368 for channel assignments. For example, to use SSI1 Receive on channel 8 instead of UART0, set bit 8 of the DMACHASGN register. 8.4 Register Map Table 8-13 on page 389 lists the μDMA channel control structures and registers. The channel control structure shows the layout of one entry in the channel control table. The channel control table is located in system memory, and the location is determined by the application, that is, the base address is n/a (not applicable). In the table below, the offset for the channel control structures is the offset from the entry in the channel control table. See “Channel Configuration” on page 371 and Table 8-3 on page 371 for a description of how the entries in the channel control table are located in memory. The μDMA register addresses are given as a hexadecimal increment, relative to the μDMA base address of 0x400F.F000. Note that the μDMA module clock must be enabled before the registers can be programmed (see page 277). There must be a delay of 3 system clocks after the μDMA module clock is enabled before any μDMA module registers are accessed. 388 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Table 8-13. μDMA Register Map Offset Name Type Reset Description See page μDMA Channel Control Structure (Offset from Channel Control Table Base) 0x000 DMASRCENDP R/W - DMA Channel Source Address End Pointer 391 0x004 DMADSTENDP R/W - DMA Channel Destination Address End Pointer 392 0x008 DMACHCTL R/W - DMA Channel Control Word 393 DMA Status 398 DMA Configuration 400 μDMA Registers (Offset from μDMA Base Address) 0x000 DMASTAT RO 0x001F.0000 0x004 DMACFG WO - 0x008 DMACTLBASE R/W 0x0000.0000 DMA Channel Control Base Pointer 401 0x00C DMAALTBASE RO 0x0000.0200 DMA Alternate Channel Control Base Pointer 402 0x010 DMAWAITSTAT RO 0xFFFF.FFC0 DMA Channel Wait-on-Request Status 403 0x014 DMASWREQ WO - DMA Channel Software Request 404 0x018 DMAUSEBURSTSET R/W 0x0000.0000 DMA Channel Useburst Set 405 0x01C DMAUSEBURSTCLR WO - DMA Channel Useburst Clear 406 0x020 DMAREQMASKSET R/W 0x0000.0000 DMA Channel Request Mask Set 407 0x024 DMAREQMASKCLR WO - DMA Channel Request Mask Clear 408 0x028 DMAENASET R/W 0x0000.0000 DMA Channel Enable Set 409 0x02C DMAENACLR WO - DMA Channel Enable Clear 410 0x030 DMAALTSET R/W 0x0000.0000 DMA Channel Primary Alternate Set 411 0x034 DMAALTCLR WO - DMA Channel Primary Alternate Clear 412 0x038 DMAPRIOSET R/W 0x0000.0000 DMA Channel Priority Set 413 0x03C DMAPRIOCLR WO - DMA Channel Priority Clear 414 0x04C DMAERRCLR R/W 0x0000.0000 DMA Bus Error Clear 415 0x500 DMACHASGN R/W 0x0000.0000 DMA Channel Assignment 416 0x504 DMACHIS R/W1C 0x0000.0000 DMA Channel Interrupt Status 417 0xFD0 DMAPeriphID4 RO 0x0000.0004 DMA Peripheral Identification 4 422 0xFE0 DMAPeriphID0 RO 0x0000.0030 DMA Peripheral Identification 0 418 0xFE4 DMAPeriphID1 RO 0x0000.00B2 DMA Peripheral Identification 1 419 0xFE8 DMAPeriphID2 RO 0x0000.000B DMA Peripheral Identification 2 420 0xFEC DMAPeriphID3 RO 0x0000.0000 DMA Peripheral Identification 3 421 0xFF0 DMAPCellID0 RO 0x0000.000D DMA PrimeCell Identification 0 423 0xFF4 DMAPCellID1 RO 0x0000.00F0 DMA PrimeCell Identification 1 424 0xFF8 DMAPCellID2 RO 0x0000.0005 DMA PrimeCell Identification 2 425 July 03, 2014 389 Texas Instruments-Production Data Micro Direct Memory Access (μDMA) Table 8-13. μDMA Register Map (continued) Offset Name 0xFFC DMAPCellID3 8.5 Type Reset RO 0x0000.00B1 Description DMA PrimeCell Identification 3 See page 426 μDMA Channel Control Structure The μDMA Channel Control Structure holds the transfer settings for a μDMA channel. Each channel has two control structures, which are located in a table in system memory. Refer to “Channel Configuration” on page 371 for an explanation of the Channel Control Table and the Channel Control Structure. The channel control structure is one entry in the channel control table. Each channel has a primary and alternate structure. The primary control structures are located at offsets 0x0, 0x10, 0x20 and so on. The alternate control structures are located at offsets 0x200, 0x210, 0x220, and so on. 390 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 1: DMA Channel Source Address End Pointer (DMASRCENDP), offset 0x000 DMA Channel Source Address End Pointer (DMASRCENDP) is part of the Channel Control Structure and is used to specify the source address for a μDMA transfer. The μDMA controller can transfer data to and from the on-chip SRAM. However, because the Flash memory and ROM are located on a separate internal bus, it is not possible to transfer data from the Flash memory or ROM with the μDMA controller. Note: The offset specified is from the base address of the control structure in system memory, not the μDMA module base address. DMA Channel Source Address End Pointer (DMASRCENDP) Base n/a Offset 0x000 Type R/W, reset 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - 7 6 5 4 3 2 1 0 R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - ADDR Type Reset R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - 15 14 13 12 11 10 9 8 ADDR Type Reset R/W - R/W - R/W - R/W - R/W - R/W - R/W - Bit/Field Name Type Reset 31:0 ADDR R/W - R/W - Description Source Address End Pointer This field points to the last address of the μDMA transfer source (inclusive). If the source address is not incrementing (the SRCINC field in the DMACHCTL register is 0x3), then this field points at the source location itself (such as a peripheral data register). July 03, 2014 391 Texas Instruments-Production Data Micro Direct Memory Access (μDMA) Register 2: DMA Channel Destination Address End Pointer (DMADSTENDP), offset 0x004 DMA Channel Destination Address End Pointer (DMADSTENDP) is part of the Channel Control Structure and is used to specify the destination address for a μDMA transfer. Note: The offset specified is from the base address of the control structure in system memory, not the μDMA module base address. DMA Channel Destination Address End Pointer (DMADSTENDP) Base n/a Offset 0x004 Type R/W, reset 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - ADDR Type Reset ADDR Type Reset Bit/Field Name Type Reset 31:0 ADDR R/W - Description Destination Address End Pointer This field points to the last address of the μDMA transfer destination (inclusive). If the destination address is not incrementing (the DSTINC field in the DMACHCTL register is 0x3), then this field points at the destination location itself (such as a peripheral data register). 392 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 3: DMA Channel Control Word (DMACHCTL), offset 0x008 DMA Channel Control Word (DMACHCTL) is part of the Channel Control Structure and is used to specify parameters of a μDMA transfer. Note: The offset specified is from the base address of the control structure in system memory, not the μDMA module base address. DMA Channel Control Word (DMACHCTL) Base n/a Offset 0x008 Type R/W, reset 31 30 DSTINC 28 27 DSTSIZE 26 24 23 22 21 SRCSIZE 20 19 18 17 reserved 16 ARBSIZE R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 ARBSIZE Type Reset 25 SRCINC R/W - R/W - NXTUSEBURST Type Reset 29 XFERSIZE R/W - R/W - R/W - R/W - R/W - Bit/Field Name Type Reset 31:30 DSTINC R/W - R/W - R/W - R/W - R/W - R/W - R/W - XFERMODE R/W - R/W - R/W - Description Destination Address Increment This field configures the destination address increment. The address increment value must be equal or greater than the value of the destination size (DSTSIZE). Value Description 0x0 Byte Increment by 8-bit locations 0x1 Half-word Increment by 16-bit locations 0x2 Word Increment by 32-bit locations 0x3 No increment Address remains set to the value of the Destination Address End Pointer (DMADSTENDP) for the channel July 03, 2014 393 Texas Instruments-Production Data Micro Direct Memory Access (μDMA) Bit/Field Name Type Reset 29:28 DSTSIZE R/W - Description Destination Data Size This field configures the destination item data size. Note: DSTSIZE must be the same as SRCSIZE. Value Description 0x0 Byte 8-bit data size 0x1 Half-word 16-bit data size 0x2 Word 32-bit data size 0x3 27:26 SRCINC R/W - Reserved Source Address Increment This field configures the source address increment. The address increment value must be equal or greater than the value of the source size (SRCSIZE). Value Description 0x0 Byte Increment by 8-bit locations 0x1 Half-word Increment by 16-bit locations 0x2 Word Increment by 32-bit locations 0x3 No increment Address remains set to the value of the Source Address End Pointer (DMASRCENDP) for the channel 25:24 SRCSIZE R/W - Source Data Size This field configures the source item data size. Note: DSTSIZE must be the same as SRCSIZE. Value Description 0x0 Byte 8-bit data size. 0x1 Half-word 16-bit data size. 0x2 Word 32-bit data size. 0x3 23:18 reserved R/W - Reserved Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 394 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Bit/Field Name Type Reset 17:14 ARBSIZE R/W - Description Arbitration Size This field configures the number of transfers that can occur before the μDMA controller re-arbitrates. The possible arbitration rate configurations represent powers of 2 and are shown below. Value Description 0x0 1 Transfer Arbitrates after each μDMA transfer 0x1 2 Transfers 0x2 4 Transfers 0x3 8 Transfers 0x4 16 Transfers 0x5 32 Transfers 0x6 64 Transfers 0x7 128 Transfers 0x8 256 Transfers 0x9 512 Transfers 0xA-0xF 1024 Transfers In this configuration, no arbitration occurs during the μDMA transfer because the maximum transfer size is 1024. 13:4 XFERSIZE R/W - Transfer Size (minus 1) This field configures the total number of items to transfer. The value of this field is 1 less than the number to transfer (value 0 means transfer 1 item). The maximum value for this 10-bit field is 1023 which represents a transfer size of 1024 items. The transfer size is the number of items, not the number of bytes. If the data size is 32 bits, then this value is the number of 32-bit words to transfer. The μDMA controller updates this field immediately prior to entering the arbitration process, so it contains the number of outstanding items that is necessary to complete the μDMA cycle. 3 NXTUSEBURST R/W - Next Useburst This field controls whether the Useburst SET[n] bit is automatically set for the last transfer of a peripheral scatter-gather operation. Normally, for the last transfer, if the number of remaining items to transfer is less than the arbitration size, the μDMA controller uses single transfers to complete the transaction. If this bit is set, then the controller uses a burst transfer to complete the last transfer. July 03, 2014 395 Texas Instruments-Production Data Micro Direct Memory Access (μDMA) Bit/Field Name Type Reset 2:0 XFERMODE R/W - Description μDMA Transfer Mode This field configures the operating mode of the μDMA cycle. Refer to “Transfer Modes” on page 372 for a detailed explanation of transfer modes. Because this register is in system RAM, it has no reset value. Therefore, this field should be initialized to 0 before the channel is enabled. Value Description 0x0 Stop 0x1 Basic 0x2 Auto-Request 0x3 Ping-Pong 0x4 Memory Scatter-Gather 0x5 Alternate Memory Scatter-Gather 0x6 Peripheral Scatter-Gather 0x7 Alternate Peripheral Scatter-Gather XFERMODE Bit Field Values. Stop Channel is stopped or configuration data is invalid. No more transfers can occur. Basic For each trigger (whether from a peripheral or a software request), the μDMA controller performs the number of transfers specified by the ARBSIZE field. Auto-Request The initial request (software- or peripheral-initiated) is sufficient to complete the entire transfer of XFERSIZE items without any further requests. Ping-Pong This mode uses both the primary and alternate control structures for this channel. When the number of transfers specified by the XFERSIZE field have completed for the current control structure (primary or alternate), the µDMA controller switches to the other one. These switches continue until one of the control structures is not set to ping-pong mode. At that point, the µDMA controller stops. An interrupt is generated on completion of the transfers configured by each control structure. See “Ping-Pong” on page 373. Memory Scatter-Gather When using this mode, the primary control structure for the channel is configured to allow a list of operations (tasks) to be performed. The source address pointer specifies the start of a table of tasks to be copied to the alternate control structure for this channel. The XFERMODE field for the alternate control structure should be configured to 0x5 (Alternate memory scatter-gather) to perform the task. When the task completes, the µDMA switches back to the primary channel control structure, which then copies the next task to the alternate control structure. This process continues until the table of tasks is empty. The last task must have an XFERMODE value other than 0x5. Note that for continuous operation, the last task can update the primary channel control structure back to the start of the list or to another list. See “Memory Scatter-Gather” on page 374. 396 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Alternate Memory Scatter-Gather This value must be used in the alternate channel control data structure when the μDMA controller operates in Memory Scatter-Gather mode. Peripheral Scatter-Gather This value must be used in the primary channel control data structure when the μDMA controller operates in Peripheral Scatter-Gather mode. In this mode, the μDMA controller operates exactly the same as in Memory Scatter-Gather mode, except that instead of performing the number of transfers specified by the XFERSIZE field in the alternate control structure at one time, the μDMA controller only performs the number of transfers specified by the ARBSIZE field per trigger; see Basic mode for details. See “Peripheral Scatter-Gather” on page 378. Alternate Peripheral Scatter-Gather This value must be used in the alternate channel control data structure when the μDMA controller operates in Peripheral Scatter-Gather mode. 8.6 μDMA Register Descriptions The register addresses given are relative to the μDMA base address of 0x400F.F000. July 03, 2014 397 Texas Instruments-Production Data Micro Direct Memory Access (μDMA) Register 4: DMA Status (DMASTAT), offset 0x000 The DMA Status (DMASTAT) register returns the status of the μDMA controller. You cannot read this register when the μDMA controller is in the reset state. DMA Status (DMASTAT) Base 0x400F.F000 Offset 0x000 Type RO, reset 0x001F.0000 31 30 29 28 27 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 RO 0 RO 0 RO 0 RO 0 26 25 24 23 22 21 20 19 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 1 RO 1 10 9 8 7 6 5 4 3 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 reserved Type Reset STATE RO 0 17 16 RO 1 RO 1 RO 1 2 1 0 DMACHANS reserved Type Reset 18 reserved RO 0 MASTEN RO 0 RO 0 Bit/Field Name Type Reset Description 31:21 reserved RO 0x000 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 20:16 DMACHANS RO 0x1F Available μDMA Channels Minus 1 This field contains a value equal to the number of μDMA channels the μDMA controller is configured to use, minus one. The value of 0x1F corresponds to 32 μDMA channels. 15:8 reserved RO 0x00 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 7:4 STATE RO 0x0 Control State Machine Status This field shows the current status of the control state machine. Status can be one of the following. Value Description 0x0 Idle 0x1 Reading channel controller data. 0x2 Reading source end pointer. 0x3 Reading destination end pointer. 0x4 Reading source data. 0x5 Writing destination data. 0x6 Waiting for µDMA request to clear. 0x7 Writing channel controller data. 0x8 Stalled 0x9 Done 0xA-0xF Undefined 3:1 reserved RO 0x0 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 398 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Bit/Field Name Type Reset 0 MASTEN RO 0 Description Master Enable Status Value Description 0 The μDMA controller is disabled. 1 The μDMA controller is enabled. July 03, 2014 399 Texas Instruments-Production Data Micro Direct Memory Access (μDMA) Register 5: DMA Configuration (DMACFG), offset 0x004 The DMACFG register controls the configuration of the μDMA controller. DMA Configuration (DMACFG) Base 0x400F.F000 Offset 0x004 Type WO, reset 31 30 29 28 27 26 25 24 WO - WO - WO - WO - WO - WO - WO - WO - 15 14 13 12 11 10 9 8 WO - WO - WO - WO - WO - WO - WO - 23 22 21 20 19 18 17 16 WO - WO - WO - WO - WO - WO - WO - WO - 7 6 5 4 3 2 1 0 WO - WO - WO - WO - WO - WO - WO - reserved Type Reset reserved Type Reset WO - MASTEN WO - Bit/Field Name Type Reset Description 31:1 reserved WO - Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 0 MASTEN WO - Controller Master Enable Value Description 0 Disables the μDMA controller. 1 Enables μDMA controller. 400 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 6: DMA Channel Control Base Pointer (DMACTLBASE), offset 0x008 The DMACTLBASE register must be configured so that the base pointer points to a location in system memory. The amount of system memory that must be assigned to the μDMA controller depends on the number of μDMA channels used and whether the alternate channel control data structure is used. See “Channel Configuration” on page 371 for details about the Channel Control Table. The base address must be aligned on a 1024-byte boundary. This register cannot be read when the μDMA controller is in the reset state. DMA Channel Control Base Pointer (DMACTLBASE) Base 0x400F.F000 Offset 0x008 Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 ADDR Type Reset R/W 0 R/W 0 R/W 0 15 14 13 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 12 11 10 9 8 7 6 5 4 3 2 1 0 RO 0 RO 0 RO 0 RO 0 RO 0 ADDR Type Reset R/W 0 R/W 0 R/W 0 reserved R/W 0 R/W 0 R/W 0 RO 0 Bit/Field Name Type Reset 31:10 ADDR R/W 0x0000.00 RO 0 RO 0 RO 0 RO 0 Description Channel Control Base Address This field contains the pointer to the base address of the channel control table. The base address must be 1024-byte aligned. 9:0 reserved RO 0x00 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. July 03, 2014 401 Texas Instruments-Production Data Micro Direct Memory Access (μDMA) Register 7: DMA Alternate Channel Control Base Pointer (DMAALTBASE), offset 0x00C The DMAALTBASE register returns the base address of the alternate channel control data. This register removes the necessity for application software to calculate the base address of the alternate channel control structures. This register cannot be read when the μDMA controller is in the reset state. DMA Alternate Channel Control Base Pointer (DMAALTBASE) Base 0x400F.F000 Offset 0x00C Type RO, reset 0x0000.0200 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 7 6 5 4 3 2 1 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 ADDR Type Reset RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 8 ADDR Type Reset RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 Bit/Field Name Type 31:0 ADDR RO RO 1 Reset RO 0 Description 0x0000.0200 Alternate Channel Address Pointer This field provides the base address of the alternate channel control structures. 402 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 8: DMA Channel Wait-on-Request Status (DMAWAITSTAT), offset 0x010 This read-only register indicates that the μDMA channel is waiting on a request. A peripheral can hold off the μDMA from performing a single request until the peripheral is ready for a burst request to enhance the μDMA performance. The use of this feature is dependent on the design of the peripheral and is not controllable by software in any way. This register cannot be read when the μDMA controller is in the reset state. DMA Channel Wait-on-Request Status (DMAWAITSTAT) Base 0x400F.F000 Offset 0x010 Type RO, reset 0xFFFF.FFC0 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 WAITREQ[n] Type Reset RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 15 14 13 12 11 10 9 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 8 7 6 5 4 3 2 1 0 RO 1 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 WAITREQ[n] Type Reset RO 1 RO 1 RO 1 RO 1 RO 1 RO 1 Bit/Field Name Type 31:0 WAITREQ[n] RO RO 1 Reset RO 1 RO 1 Description 0xFFFF.FFC0 Channel [n] Wait Status These bits provide the channel wait-on-request status. Bit 0 corresponds to channel 0. Value Description 1 The corresponding channel is waiting on a request. 0 The corresponding channel is not waiting on a request. July 03, 2014 403 Texas Instruments-Production Data Micro Direct Memory Access (μDMA) Register 9: DMA Channel Software Request (DMASWREQ), offset 0x014 Each bit of the DMASWREQ register represents the corresponding μDMA channel. Setting a bit generates a request for the specified μDMA channel. DMA Channel Software Request (DMASWREQ) Base 0x400F.F000 Offset 0x014 Type WO, reset 31 30 29 28 27 26 25 24 WO - WO - WO - WO - WO - WO - WO - WO - 15 14 13 12 11 10 9 8 WO - WO - WO - WO - WO - WO - WO - WO - 23 22 21 20 19 18 17 16 WO - WO - WO - WO - WO - WO - WO - WO - 7 6 5 4 3 2 1 0 WO - WO - WO - WO - WO - WO - WO - SWREQ[n] Type Reset SWREQ[n] Type Reset Bit/Field Name Type Reset 31:0 SWREQ[n] WO - WO - Description Channel [n] Software Request These bits generate software requests. Bit 0 corresponds to channel 0. Value Description 1 Generate a software request for the corresponding channel. 0 No request generated. These bits are automatically cleared when the software request has been completed. 404 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 10: DMA Channel Useburst Set (DMAUSEBURSTSET), offset 0x018 Each bit of the DMAUSEBURSTSET register represents the corresponding μDMA channel. Setting a bit disables the channel's single request input from generating requests, configuring the channel to only accept burst requests. Reading the register returns the status of USEBURST. If the amount of data to transfer is a multiple of the arbitration (burst) size, the corresponding SET[n] bit is cleared after completing the final transfer. If there are fewer items remaining to transfer than the arbitration (burst) size, the μDMA controller automatically clears the corresponding SET[n] bit, allowing the remaining items to transfer using single requests. In order to resume transfers using burst requests, the corresponding bit must be set again. A bit should not be set if the corresponding peripheral does not support the burst request model. Refer to “Request Types” on page 370 for more details about request types. DMA Channel Useburst Set (DMAUSEBURSTSET) Base 0x400F.F000 Offset 0x018 Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 SET[n] Type Reset SET[n] Type Reset Bit/Field Name Type 31:0 SET[n] R/W Reset Description 0x0000.0000 Channel [n] Useburst Set Value Description 0 μDMA channel [n] responds to single or burst requests. 1 μDMA channel [n] responds only to burst requests. Bit 0 corresponds to channel 0. This bit is automatically cleared as described above. A bit can also be manually cleared by setting the corresponding CLR[n] bit in the DMAUSEBURSTCLR register. July 03, 2014 405 Texas Instruments-Production Data Micro Direct Memory Access (μDMA) Register 11: DMA Channel Useburst Clear (DMAUSEBURSTCLR), offset 0x01C Each bit of the DMAUSEBURSTCLR register represents the corresponding μDMA channel. Setting a bit clears the corresponding SET[n] bit in the DMAUSEBURSTSET register. DMA Channel Useburst Clear (DMAUSEBURSTCLR) Base 0x400F.F000 Offset 0x01C Type WO, reset 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 WO - WO - WO - WO - WO - WO - WO - WO - WO - WO - WO - WO - WO - WO - WO - WO - 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 WO - WO - WO - WO - WO - WO - WO - WO - WO - WO - WO - WO - WO - WO - WO - WO - CLR[n] Type Reset CLR[n] Type Reset Bit/Field Name Type Reset 31:0 CLR[n] WO - Description Channel [n] Useburst Clear Value Description 0 No effect. 1 Setting a bit clears the corresponding SET[n] bit in the DMAUSEBURSTSET register meaning that µDMA channel [n] responds to single and burst requests. 406 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 12: DMA Channel Request Mask Set (DMAREQMASKSET), offset 0x020 Each bit of the DMAREQMASKSET register represents the corresponding μDMA channel. Setting a bit disables μDMA requests for the channel. Reading the register returns the request mask status. When a μDMA channel's request is masked, that means the peripheral can no longer request μDMA transfers. The channel can then be used for software-initiated transfers. DMA Channel Request Mask Set (DMAREQMASKSET) Base 0x400F.F000 Offset 0x020 Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 SET[n] Type Reset R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 SET[n] Type Reset R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 Bit/Field Name Type 31:0 SET[n] R/W R/W 0 Reset R/W 0 Description 0x0000.0000 Channel [n] Request Mask Set Value Description 0 The peripheral associated with channel [n] is enabled to request μDMA transfers. 1 The peripheral associated with channel [n] is not able to request μDMA transfers. Channel [n] may be used for software-initiated transfers. Bit 0 corresponds to channel 0. A bit can only be cleared by setting the corresponding CLR[n] bit in the DMAREQMASKCLR register. July 03, 2014 407 Texas Instruments-Production Data Micro Direct Memory Access (μDMA) Register 13: DMA Channel Request Mask Clear (DMAREQMASKCLR), offset 0x024 Each bit of the DMAREQMASKCLR register represents the corresponding μDMA channel. Setting a bit clears the corresponding SET[n] bit in the DMAREQMASKSET register. DMA Channel Request Mask Clear (DMAREQMASKCLR) Base 0x400F.F000 Offset 0x024 Type WO, reset 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 WO - WO - WO - WO - WO - WO - WO - WO - 7 6 5 4 3 2 1 0 WO - WO - WO - WO - WO - WO - WO - WO - CLR[n] Type Reset WO - WO - WO - WO - WO - WO - WO - WO - 15 14 13 12 11 10 9 8 CLR[n] Type Reset WO - WO - WO - WO - WO - WO - WO - Bit/Field Name Type Reset 31:0 CLR[n] WO - WO - Description Channel [n] Request Mask Clear Value Description 0 No effect. 1 Setting a bit clears the corresponding SET[n] bit in the DMAREQMASKSET register meaning that the peripheral associated with channel [n] is enabled to request μDMA transfers. 408 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 14: DMA Channel Enable Set (DMAENASET), offset 0x028 Each bit of the DMAENASET register represents the corresponding µDMA channel. Setting a bit enables the corresponding µDMA channel. Reading the register returns the enable status of the channels. If a channel is enabled but the request mask is set (DMAREQMASKSET), then the channel can be used for software-initiated transfers. DMA Channel Enable Set (DMAENASET) Base 0x400F.F000 Offset 0x028 Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 SET[n] Type Reset SET[n] Type Reset Bit/Field Name Type 31:0 SET[n] R/W Reset Description 0x0000.0000 Channel [n] Enable Set Value Description 0 µDMA Channel [n] is disabled. 1 µDMA Channel [n] is enabled. Bit 0 corresponds to channel 0. A bit can only be cleared by setting the corresponding CLR[n] bit in the DMAENACLR register. July 03, 2014 409 Texas Instruments-Production Data Micro Direct Memory Access (μDMA) Register 15: DMA Channel Enable Clear (DMAENACLR), offset 0x02C Each bit of the DMAENACLR register represents the corresponding µDMA channel. Setting a bit clears the corresponding SET[n] bit in the DMAENASET register. DMA Channel Enable Clear (DMAENACLR) Base 0x400F.F000 Offset 0x02C Type WO, reset 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 WO - WO - WO - WO - WO - WO - WO - WO - WO - WO - WO - WO - WO - WO - WO - WO - 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 WO - WO - WO - WO - WO - WO - WO - WO - WO - WO - WO - WO - WO - WO - WO - WO - CLR[n] Type Reset CLR[n] Type Reset Bit/Field Name Type Reset 31:0 CLR[n] WO - Description Clear Channel [n] Enable Clear Value Description 0 No effect. 1 Setting a bit clears the corresponding SET[n] bit in the DMAENASET register meaning that channel [n] is disabled for μDMA transfers. Note: The controller disables a channel when it completes the μDMA cycle. 410 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 16: DMA Channel Primary Alternate Set (DMAALTSET), offset 0x030 Each bit of the DMAALTSET register represents the corresponding µDMA channel. Setting a bit configures the µDMA channel to use the alternate control data structure. Reading the register returns the status of which control data structure is in use for the corresponding µDMA channel. DMA Channel Primary Alternate Set (DMAALTSET) Base 0x400F.F000 Offset 0x030 Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 SET[n] Type Reset SET[n] Type Reset Bit/Field Name Type 31:0 SET[n] R/W Reset Description 0x0000.0000 Channel [n] Alternate Set Value Description 0 µDMA channel [n] is using the primary control structure. 1 µDMA channel [n] is using the alternate control structure. Bit 0 corresponds to channel 0. A bit can only be cleared by setting the corresponding CLR[n] bit in the DMAALTCLR register. Note: For Ping-Pong and Scatter-Gather cycle types, the µDMA controller automatically sets these bits to select the alternate channel control data structure. July 03, 2014 411 Texas Instruments-Production Data Micro Direct Memory Access (μDMA) Register 17: DMA Channel Primary Alternate Clear (DMAALTCLR), offset 0x034 Each bit of the DMAALTCLR register represents the corresponding μDMA channel. Setting a bit clears the corresponding SET[n] bit in the DMAALTSET register. DMA Channel Primary Alternate Clear (DMAALTCLR) Base 0x400F.F000 Offset 0x034 Type WO, reset 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 WO - WO - WO - WO - WO - WO - WO - WO - 7 6 5 4 3 2 1 0 WO - WO - WO - WO - WO - WO - WO - WO - CLR[n] Type Reset WO - WO - WO - WO - WO - WO - WO - WO - 15 14 13 12 11 10 9 8 CLR[n] Type Reset WO - WO - WO - WO - WO - WO - WO - Bit/Field Name Type Reset 31:0 CLR[n] WO - WO - Description Channel [n] Alternate Clear Value Description 0 No effect. 1 Setting a bit clears the corresponding SET[n] bit in the DMAALTSET register meaning that channel [n] is using the primary control structure. Note: For Ping-Pong and Scatter-Gather cycle types, the µDMA controller automatically sets these bits to select the alternate channel control data structure. 412 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 18: DMA Channel Priority Set (DMAPRIOSET), offset 0x038 Each bit of the DMAPRIOSET register represents the corresponding µDMA channel. Setting a bit configures the µDMA channel to have a high priority level. Reading the register returns the status of the channel priority mask. DMA Channel Priority Set (DMAPRIOSET) Base 0x400F.F000 Offset 0x038 Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 SET[n] Type Reset SET[n] Type Reset Bit/Field Name Type 31:0 SET[n] R/W Reset Description 0x0000.0000 Channel [n] Priority Set Value Description 0 µDMA channel [n] is using the default priority level. 1 µDMA channel [n] is using a high priority level. Bit 0 corresponds to channel 0. A bit can only be cleared by setting the corresponding CLR[n] bit in the DMAPRIOCLR register. July 03, 2014 413 Texas Instruments-Production Data Micro Direct Memory Access (μDMA) Register 19: DMA Channel Priority Clear (DMAPRIOCLR), offset 0x03C Each bit of the DMAPRIOCLR register represents the corresponding µDMA channel. Setting a bit clears the corresponding SET[n] bit in the DMAPRIOSET register. DMA Channel Priority Clear (DMAPRIOCLR) Base 0x400F.F000 Offset 0x03C Type WO, reset 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 WO - WO - WO - WO - WO - WO - WO - WO - WO - WO - WO - WO - WO - WO - WO - WO - 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 WO - WO - WO - WO - WO - WO - WO - WO - WO - WO - WO - WO - WO - WO - WO - WO - CLR[n] Type Reset CLR[n] Type Reset Bit/Field Name Type Reset 31:0 CLR[n] WO - Description Channel [n] Priority Clear Value Description 0 No effect. 1 Setting a bit clears the corresponding SET[n] bit in the DMAPRIOSET register meaning that channel [n] is using the default priority level. 414 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 20: DMA Bus Error Clear (DMAERRCLR), offset 0x04C The DMAERRCLR register is used to read and clear the µDMA bus error status. The error status is set if the μDMA controller encountered a bus error while performing a transfer. If a bus error occurs on a channel, that channel is automatically disabled by the μDMA controller. The other channels are unaffected. DMA Bus Error Clear (DMAERRCLR) Base 0x400F.F000 Offset 0x04C Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 8 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 7 6 5 4 3 2 1 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 reserved Type Reset reserved Type Reset Bit/Field Name Type Reset 31:1 reserved RO 0x0000.000 0 ERRCLR R/W1C 0 RO 0 ERRCLR R/W1C 0 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. μDMA Bus Error Status Value Description 0 No bus error is pending. 1 A bus error is pending. This bit is cleared by writing a 1 to it. July 03, 2014 415 Texas Instruments-Production Data Micro Direct Memory Access (μDMA) Register 21: DMA Channel Assignment (DMACHASGN), offset 0x500 Each bit of the DMACHASGN register represents the corresponding µDMA channel. Setting a bit selects the secondary channel assignment as specified in Table 8-1 on page 368. DMA Channel Assignment (DMACHASGN) Base 0x400F.F000 Offset 0x500 Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - 15 14 13 12 11 10 9 8 R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - 23 22 21 20 19 18 17 16 R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - 7 6 5 4 3 2 1 0 R/W - R/W - R/W - R/W - R/W - R/W - R/W - CHASGN[n] Type Reset CHASGN[n] Type Reset Bit/Field Name Type Reset 31:0 CHASGN[n] R/W - R/W - Description Channel [n] Assignment Select Value Description 0 Use the primary channel assignment. 1 Use the secondary channel assignment. 416 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 22: DMA Channel Interrupt Status (DMACHIS), offset 0x504 Each bit of the DMACHIS register represents the corresponding µDMA channel. A bit is set when that μDMA channel causes a completion interrupt. The bits are cleared by a writing a 1. DMA Channel Interrupt Status (DMACHIS) Base 0x400F.F000 Offset 0x504 Type R/W1C, reset 0x0000.0000 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 R/W1C 0 R/W1C 0 R/W1C 0 R/W1C 0 R/W1C 0 R/W1C 0 R/W1C 0 R/W1C 0 R/W1C 0 R/W1C 0 R/W1C 0 R/W1C 0 R/W1C 0 R/W1C 0 R/W1C 0 R/W1C 0 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 R/W1C 0 R/W1C 0 R/W1C 0 R/W1C 0 R/W1C 0 R/W1C 0 R/W1C 0 R/W1C 0 R/W1C 0 R/W1C 0 R/W1C 0 R/W1C 0 R/W1C 0 R/W1C 0 R/W1C 0 R/W1C 0 CHIS[n] Type Reset CHIS[n] Type Reset Bit/Field Name Type 31:0 CHIS[n] R/W1C Reset Description 0x0000.0000 Channel [n] Interrupt Status Value Description 1 The corresponding μDMA channel caused an interrupt. 0 The corresponding μDMA channel has not caused an interrupt. This bit is cleared by writing a 1 to it. July 03, 2014 417 Texas Instruments-Production Data Micro Direct Memory Access (μDMA) Register 23: DMA Peripheral Identification 0 (DMAPeriphID0), offset 0xFE0 The DMAPeriphIDn registers are hard-coded, and the fields within the registers determine the reset values. DMA Peripheral Identification 0 (DMAPeriphID0) Base 0x400F.F000 Offset 0xFE0 Type RO, reset 0x0000.0030 31 30 29 28 27 26 25 24 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 8 7 6 5 4 3 2 1 0 RO 0 RO 0 RO 0 RO 1 RO 1 RO 0 RO 0 RO 0 RO 0 reserved Type Reset reserved Type Reset PID0 RO 0 Bit/Field Name Type Reset 31:8 reserved RO 0x0000.00 7:0 PID0 RO 0x30 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. μDMA Peripheral ID Register [7:0] Can be used by software to identify the presence of this peripheral. 418 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 24: DMA Peripheral Identification 1 (DMAPeriphID1), offset 0xFE4 The DMAPeriphIDn registers are hard-coded, and the fields within the registers determine the reset values. DMA Peripheral Identification 1 (DMAPeriphID1) Base 0x400F.F000 Offset 0xFE4 Type RO, reset 0x0000.00B2 31 30 29 28 27 26 25 24 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 8 7 6 5 4 3 2 1 0 RO 0 RO 1 RO 0 RO 1 RO 1 RO 0 RO 0 RO 1 RO 0 reserved Type Reset reserved Type Reset PID1 RO 0 Bit/Field Name Type Reset 31:8 reserved RO 0x0000.00 7:0 PID1 RO 0xB2 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. μDMA Peripheral ID Register [15:8] Can be used by software to identify the presence of this peripheral. July 03, 2014 419 Texas Instruments-Production Data Micro Direct Memory Access (μDMA) Register 25: DMA Peripheral Identification 2 (DMAPeriphID2), offset 0xFE8 The DMAPeriphIDn registers are hard-coded, and the fields within the registers determine the reset values. DMA Peripheral Identification 2 (DMAPeriphID2) Base 0x400F.F000 Offset 0xFE8 Type RO, reset 0x0000.000B 31 30 29 28 27 26 25 24 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 8 7 6 5 4 3 2 1 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 1 RO 0 RO 1 RO 1 reserved Type Reset reserved Type Reset PID2 RO 0 Bit/Field Name Type Reset 31:8 reserved RO 0x0000.00 7:0 PID2 RO 0x0B Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. μDMA Peripheral ID Register [23:16] Can be used by software to identify the presence of this peripheral. 420 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 26: DMA Peripheral Identification 3 (DMAPeriphID3), offset 0xFEC The DMAPeriphIDn registers are hard-coded and the fields within the registers determine the reset values. DMA Peripheral Identification 3 (DMAPeriphID3) Base 0x400F.F000 Offset 0xFEC Type RO, reset 0x0000.0000 31 30 29 28 27 26 25 24 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 8 7 6 5 4 3 2 1 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 reserved Type Reset reserved Type Reset PID3 RO 0 Bit/Field Name Type Reset 31:8 reserved RO 0x0000.00 7:0 PID3 RO 0x00 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. μDMA Peripheral ID Register [31:24] Can be used by software to identify the presence of this peripheral. July 03, 2014 421 Texas Instruments-Production Data Micro Direct Memory Access (μDMA) Register 27: DMA Peripheral Identification 4 (DMAPeriphID4), offset 0xFD0 The DMAPeriphIDn registers are hard-coded, and the fields within the registers determine the reset values. DMA Peripheral Identification 4 (DMAPeriphID4) Base 0x400F.F000 Offset 0xFD0 Type RO, reset 0x0000.0004 31 30 29 28 27 26 25 24 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 8 7 6 5 4 3 2 1 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 1 RO 0 RO 0 reserved Type Reset reserved Type Reset PID4 RO 0 Bit/Field Name Type Reset 31:8 reserved RO 0x0000.00 7:0 PID4 RO 0x04 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. μDMA Peripheral ID Register Can be used by software to identify the presence of this peripheral. 422 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 28: DMA PrimeCell Identification 0 (DMAPCellID0), offset 0xFF0 The DMAPCellIDn registers are hard-coded, and the fields within the registers determine the reset values. DMA PrimeCell Identification 0 (DMAPCellID0) Base 0x400F.F000 Offset 0xFF0 Type RO, reset 0x0000.000D 31 30 29 28 27 26 25 24 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 8 7 6 5 4 3 2 1 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 1 RO 1 RO 0 RO 1 reserved Type Reset reserved Type Reset CID0 RO 0 Bit/Field Name Type Reset 31:8 reserved RO 0x0000.00 7:0 CID0 RO 0x0D Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. μDMA PrimeCell ID Register [7:0] Provides software a standard cross-peripheral identification system. July 03, 2014 423 Texas Instruments-Production Data Micro Direct Memory Access (μDMA) Register 29: DMA PrimeCell Identification 1 (DMAPCellID1), offset 0xFF4 The DMAPCellIDn registers are hard-coded, and the fields within the registers determine the reset values. DMA PrimeCell Identification 1 (DMAPCellID1) Base 0x400F.F000 Offset 0xFF4 Type RO, reset 0x0000.00F0 31 30 29 28 27 26 25 24 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 8 7 6 5 4 3 2 1 0 RO 0 RO 1 RO 1 RO 1 RO 1 RO 0 RO 0 RO 0 RO 0 reserved Type Reset reserved Type Reset CID1 RO 0 Bit/Field Name Type Reset 31:8 reserved RO 0x0000.00 7:0 CID1 RO 0xF0 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. μDMA PrimeCell ID Register [15:8] Provides software a standard cross-peripheral identification system. 424 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 30: DMA PrimeCell Identification 2 (DMAPCellID2), offset 0xFF8 The DMAPCellIDn registers are hard-coded, and the fields within the registers determine the reset values. DMA PrimeCell Identification 2 (DMAPCellID2) Base 0x400F.F000 Offset 0xFF8 Type RO, reset 0x0000.0005 31 30 29 28 27 26 25 24 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 8 7 6 5 4 3 2 1 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 1 RO 0 RO 1 reserved Type Reset reserved Type Reset CID2 RO 0 Bit/Field Name Type Reset Description 31:8 reserved RO 0x00 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 7:0 CID2 RO 0x05 μDMA PrimeCell ID Register [23:16] Provides software a standard cross-peripheral identification system. July 03, 2014 425 Texas Instruments-Production Data Micro Direct Memory Access (μDMA) Register 31: DMA PrimeCell Identification 3 (DMAPCellID3), offset 0xFFC The DMAPCellIDn registers are hard-coded, and the fields within the registers determine the reset values. DMA PrimeCell Identification 3 (DMAPCellID3) Base 0x400F.F000 Offset 0xFFC Type RO, reset 0x0000.00B1 31 30 29 28 27 26 25 24 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 8 7 6 5 4 3 2 1 0 RO 0 RO 1 RO 0 RO 1 RO 1 RO 0 RO 0 RO 0 RO 1 reserved Type Reset reserved Type Reset CID3 RO 0 Bit/Field Name Type Reset Description 31:8 reserved RO 0x00 Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. 7:0 CID3 RO 0xB1 μDMA PrimeCell ID Register [31:24] Provides software a standard cross-peripheral identification system. 426 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller 9 General-Purpose Input/Outputs (GPIOs) The GPIO module is composed of nine physical GPIO blocks, each corresponding to an individual GPIO port (Port A, Port B, Port C, Port D, Port E, Port F, Port G, Port H, Port J). The GPIO module supports up to 60 programmable input/output pins, depending on the peripherals being used. The GPIO module has the following features: ■ Up to 60 GPIOs, depending on configuration ■ Highly flexible pin muxing allows use as GPIO or one of several peripheral functions ■ 5-V-tolerant in input configuration ■ Two means of port access: either Advanced High-Performance Bus (AHB) with better back-to-back access performance, or the legacy Advanced Peripheral Bus (APB) for backwards-compatibility with existing code ■ Fast toggle capable of a change every clock cycle for ports on AHB, every two clock cycles for ports on APB ■ Programmable control for GPIO interrupts – Interrupt generation masking – Edge-triggered on rising, falling, or both – Level-sensitive on High or Low values ■ Bit masking in both read and write operations through address lines ■ Can be used to initiate an ADC sample sequence ■ Pins configured as digital inputs are Schmitt-triggered ■ Programmable control for GPIO pad configuration – Weak pull-up or pull-down resistors – 2-mA, 4-mA, and 8-mA pad drive for digital communication; up to four pads can sink 18-mA for high-current applications – Slew rate control for the 8-mA drive – Open drain enables – Digital input enables 9.1 Signal Description GPIO signals have alternate hardware functions. The following table lists the GPIO pins and their analog and digital alternate functions. The AINx and VREFA analog signals are not 5-V tolerant and go through an isolation circuit before reaching their circuitry. These signals are configured by clearing the corresponding DEN bit in the GPIO Digital Enable (GPIODEN) register and setting the corresponding AMSEL bit in the GPIO Analog Mode Select (GPIOAMSEL) register. Other analog July 03, 2014 427 Texas Instruments-Production Data General-Purpose Input/Outputs (GPIOs) signals are 5-V tolerant and are connected directly to their circuitry (C0-, C0+, C1-, C1+, C2-, C2+, USB0VBUS, USB0ID). These signals are configured by clearing the DEN bit in the GPIO Digital Enable (GPIODEN) register. All GPIO signals are 5-V tolerant when configured as inputs except for PB0 and PB1, which are limited to 3.6 V. The digital alternate hardware functions are enabled by setting the appropriate bit in the GPIO Alternate Function Select (GPIOAFSEL) and GPIODEN registers and configuring the PMCx bit field in the GPIO Port Control (GPIOPCTL) register to the numeric encoding shown in the table below. Note that each pin must be programmed individually; no type of grouping is implied by the columns in the table. Table entries that are shaded gray are the default values for the corresponding GPIO pin. Important: All GPIO pins are configured as GPIOs and tri-stated by default (GPIOAFSEL=0, GPIODEN=0, GPIOPDR=0, GPIOPUR=0, and GPIOPCTL=0, with the exception of the pins shown in the table below. A Power-On-Reset (POR) or asserting RST puts the pins back to their default state. Table 9-1. GPIO Pins With Non-Zero Reset Values GPIO Pins Default State PA[1:0] UART0 GPIOAFSEL GPIODEN GPIOPDR GPIOPUR 0 0 0 GPIOPCTL 0 0x1 PA[5:2] SSI0 0 0 0 0 0x1 PB[3:2] I2C0 0 0 0 0 0x1 PC[3:0] JTAG/SWD 1 1 0 1 0x3 Table 9-2. GPIO Pins and Alternate Functions (100LQFP) IO Pin Analog Function a Digital Function (GPIOPCTL PMCx Bit Field Encoding) 1 2 3 4 5 6 7 8 9 10 11 PA0 26 - U0Rx - - - - - - I2C1SCL U1Rx - - PA1 27 - U0Tx - - - - - - I2C1SDA U1Tx - - PA2 28 - SSI0Clk - - - - - - - I2S0RXSD - - PA3 29 - SSI0Fss - - - - - - - I2S0RXMCLK - - PA4 30 - SSI0Rx - - - CAN0Rx - - - I2S0TXSCK - - PA5 31 - SSI0Tx - - - CAN0Tx - - - I2S0TXWS - - PA6 34 - I2C1SCL CCP1 - - - CAN0Rx - USB0EPEN U1CTS - - USB0PFLT U1DCD PA7 35 - I2C1SDA CCP4 - - - CAN0Tx CCP3 - - PB0 66 USB0ID CCP0 - - - U1Rx - - - - - - PB1 67 USB0VBUS CCP2 - - CCP1 U1Tx - - - - - - PB2 72 - I2C0SCL - - CCP3 CCP0 - - USB0EPEN - - - PB3 65 - I2C0SDA - - - - - - USB0PFLT - - - PB4 92 AIN10 C0- - - - U2Rx CAN0Rx - U1Rx EPI0S23 - - - PB5 91 AIN11 C1- C0o CCP5 CCP6 CCP0 CAN0Tx CCP2 U1Tx EPI0S22 - - - PB6 90 VREFA C0+ CCP1 CCP7 C0o - - CCP5 - - I2S0TXSCK - - PB7 89 - - - - NMI - - - - - - - PC0 80 - - - TCK SWCLK - - - - - - - - 428 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Table 9-2. GPIO Pins and Alternate Functions (100LQFP) (continued) IO Pin Analog Function PC1 79 - PC2 78 - PC3 77 - PC4 25 PC5 PC6 a Digital Function (GPIOPCTL PMCx Bit Field Encoding) 1 2 3 4 5 6 7 8 9 10 11 - - TMS SWDIO - - - - - - - - - - TDI - - - - - - - - - - TDO SWO - - - - - - - - - CCP5 - - - CCP2 CCP4 - EPI0S2 CCP1 - - 24 C1+ CCP1 C1o C0o - CCP3 USB0EPEN - EPI0S3 - - - 23 C2+ CCP3 - C2o - U1Rx CCP0 USB0PFLT EPI0S4 - - - PC7 22 C2- CCP4 - - CCP0 U1Tx USB0PFLT C1o - - - EPI0S5 PD0 10 AIN15 - CAN0Rx - U2Rx U1Rx CCP6 - I2S0RXSCK U1CTS - - PD1 11 AIN14 - CAN0Tx - U2Tx U1Tx CCP7 - I2S0RXWS U1DCD CCP2 - PD2 12 AIN13 U1Rx CCP6 - CCP5 - - - EPI0S20 - - - PD3 13 AIN12 U1Tx CCP7 - CCP0 - - - EPI0S21 - - - PD4 97 AIN7 CCP0 CCP3 - - - - - I2S0RXSD U1RI EPI0S19 - PD5 98 AIN6 CCP2 CCP4 - - - - - I2S0RXMCLK U2Rx EPI0S28 - PD6 99 AIN5 - - - - - - - I2S0TXSCK U2Tx EPI0S29 - PD7 100 AIN4 - C0o CCP1 - - - - I2S0TXWS U1DTR EPI0S30 - - - - - PE0 74 - - SSI1Clk CCP3 - - - - EPI0S8 USB0PFLT PE1 75 - - SSI1Fss - CCP2 CCP6 - - EPI0S9 - PE2 95 AIN9 CCP4 SSI1Rx - - CCP2 - - EPI0S24 - - - PE3 96 AIN8 CCP1 SSI1Tx - - CCP7 - - EPI0S25 - - - PE4 6 AIN3 CCP3 - - - U2Tx CCP2 - - I2S0TXWS - - PE5 5 AIN2 CCP5 - - - - - - - I2S0TXSD - - PE6 2 AIN1 - C1o - - - - - - U1CTS - - PE7 1 AIN0 - C2o - - - - - - U1DCD - - PF0 47 - CAN1Rx - - - - - - I2S0TXSD U1DSR - - PF1 61 - CAN1Tx - - - - - - I2S0TXMCLK U1RTS CCP3 - PF2 60 - LED1 - - - - - - - SSI1Clk - - PF3 59 - LED0 - - - - - - - SSI1Fss - - PF4 42 - CCP0 C0o - - - - - EPI0S12 SSI1Rx - - PF5 41 - CCP2 C1o - - - - - EPI0S15 SSI1Tx - - PG0 19 - U2Rx - I2C1SCL - - - - - - PG1 18 - U2Tx - I2C1SDA - - - - EPI0S14 - - - PG7 36 - - - - - - - - CCP5 EPI0S31 - - - - - USB0EPEN EPI0S13 PH0 86 - CCP6 - - - - - - EPI0S6 PH1 85 - CCP7 - - - - - - EPI0S7 - - - PH2 84 - - C1o - - - - - EPI0S1 - - - PH3 83 - - - - USB0EPEN - - - EPI0S0 - - - PH4 76 - - - - USB0PFLT - - - EPI0S10 - - SSI1Clk PH5 63 - - - - - - - - EPI0S11 - - SSI1Fss PH6 62 - - - - - - - - EPI0S26 - - SSI1Rx July 03, 2014 429 Texas Instruments-Production Data General-Purpose Input/Outputs (GPIOs) Table 9-2. GPIO Pins and Alternate Functions (100LQFP) (continued) a Digital Function (GPIOPCTL PMCx Bit Field Encoding) IO Pin Analog Function 1 2 3 4 5 6 7 8 9 10 11 PH7 15 - - - - - - - - EPI0S27 - - SSI1Tx PJ0 14 - - - - - - - - EPI0S16 - - I2C1SCL PJ1 87 - - - - - - - - EPI0S17 USB0PFLT - I2C1SDA PJ2 39 - - - - - - - - EPI0S18 - - CCP0 a. The digital signals that are shaded gray are the power-on default values for the corresponding GPIO pin. Table 9-3. GPIO Pins and Alternate Functions (108BGA) a Digital Function (GPIOPCTL PMCx Bit Field Encoding) IO Pin Analog Function 1 2 3 4 5 6 7 8 9 10 11 PA0 L3 - U0Rx - - - - - - I2C1SCL U1Rx - - PA1 M3 - U0Tx - - - - - - I2C1SDA U1Tx - - PA2 M4 - SSI0Clk - - - - - - - I2S0RXSD - - PA3 L4 - SSI0Fss - - - - - - - I2S0RXMCLK - - PA4 L5 - SSI0Rx - - - CAN0Rx - - - I2S0TXSCK - - PA5 M5 - SSI0Tx - - - CAN0Tx - - - I2S0TXWS - - PA6 L6 - I2C1SCL CCP1 - - - CAN0Rx - USB0EPEN U1CTS - - USB0PFLT U1DCD PA7 M6 - I2C1SDA CCP4 - - - CAN0Tx CCP3 PB0 E12 USB0ID CCP0 - - - U1Rx - - - - - - - - PB1 D12 USB0VBUS CCP2 - - CCP1 U1Tx - - - - - - PB2 A11 - I2C0SCL - - CCP3 CCP0 - - USB0EPEN - - - PB3 E11 - I2C0SDA - - - - - - USB0PFLT - - - PB4 A6 AIN10 C0- - - - U2Rx CAN0Rx - U1Rx EPI0S23 - - - PB5 B7 AIN11 C1- C0o CCP5 CCP6 CCP0 CAN0Tx CCP2 U1Tx EPI0S22 - - - PB6 A7 VREFA C0+ CCP1 CCP7 C0o - - CCP5 - - I2S0TXSCK - - PB7 A8 - - - - NMI - - - - - - - PC0 A9 - - - TCK SWCLK - - - - - - - - PC1 B9 - - - TMS SWDIO - - - - - - - - PC2 B8 - - - TDI - - - - - - - - PC3 A10 - - - TDO SWO - - - - - - - - PC4 L1 - CCP5 - - - CCP2 CCP4 - EPI0S2 CCP1 - - PC5 M1 C1+ CCP1 C1o C0o - CCP3 USB0EPEN - EPI0S3 - - - PC6 M2 C2+ CCP3 - C2o - U1Rx CCP0 USB0PFLT EPI0S4 - - - - PC7 L2 C2- CCP4 - - CCP0 U1Tx USB0PFLT C1o PD0 G1 AIN15 - CAN0Rx - U2Rx U1Rx CCP6 - PD1 G2 AIN14 - CAN0Tx - U2Tx U1Tx CCP7 PD2 H2 AIN13 U1Rx CCP6 - CCP5 - - 430 - - I2S0RXSCK U1CTS - - - I2S0RXWS U1DCD CCP2 - - EPI0S20 - - EPI0S5 - July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Table 9-3. GPIO Pins and Alternate Functions (108BGA) (continued) a Digital Function (GPIOPCTL PMCx Bit Field Encoding) IO Pin Analog Function 1 2 3 4 5 6 7 8 9 10 11 PD3 H1 AIN12 U1Tx CCP7 - CCP0 - - - EPI0S21 - - - PD4 B5 AIN7 CCP0 CCP3 - - - - - I2S0RXSD U1RI EPI0S19 - PD5 C6 AIN6 CCP2 CCP4 - - - - - I2S0RXMCLK U2Rx EPI0S28 - PD6 A3 AIN5 - - - - - - - I2S0TXSCK U2Tx EPI0S29 - PD7 A2 AIN4 - C0o CCP1 - - - - I2S0TXWS U1DTR EPI0S30 - PE0 B11 - - SSI1Clk CCP3 - - - - EPI0S8 USB0PFLT - - PE1 A12 - - SSI1Fss - CCP2 CCP6 - - EPI0S9 - - - PE2 A4 AIN9 CCP4 SSI1Rx - - CCP2 - - EPI0S24 - - - PE3 B4 AIN8 CCP1 SSI1Tx - - CCP7 - - EPI0S25 - - - PE4 B2 AIN3 CCP3 - - - U2Tx CCP2 - - I2S0TXWS - - PE5 B3 AIN2 CCP5 - - - - - - - I2S0TXSD - - PE6 A1 AIN1 - C1o - - - - - - U1CTS - - PE7 B1 AIN0 - C2o - - - - - - U1DCD - - PF0 M9 - CAN1Rx - - - - - - I2S0TXSD U1DSR - - I2S0TXMCLK U1RTS PF1 H12 - CAN1Tx - - - - - - CCP3 - PF2 J11 - LED1 - - - - - - - SSI1Clk - - PF3 J12 - LED0 - - - - - - - SSI1Fss - - PF4 K4 - CCP0 C0o - - - - - EPI0S12 SSI1Rx - - PF5 K3 - CCP2 C1o - - - - - EPI0S15 SSI1Tx - - PG0 K1 - U2Rx - I2C1SCL - - - PG1 K2 - U2Tx - I2C1SDA - - - PG7 C10 - - - - - - - - - - - EPI0S14 - - - - CCP5 EPI0S31 - - USB0EPEN EPI0S13 PH0 C9 - CCP6 - - - - - - EPI0S6 - - - PH1 C8 - CCP7 - - - - - - EPI0S7 - - - PH2 D11 - - C1o - - - - - EPI0S1 - - - PH3 D10 - - - - USB0EPEN - - - EPI0S0 - - - PH4 B10 - - - - USB0PFLT - - - EPI0S10 - - SSI1Clk PH5 F10 - - - - - - - - EPI0S11 - - SSI1Fss PH6 G3 - - - - - - - - EPI0S26 - - SSI1Rx PH7 H3 - - - - - - - - EPI0S27 - - SSI1Tx PJ0 F3 - - - - - - - - EPI0S16 - - I2C1SCL PJ1 B6 - - - - - - - - EPI0S17 USB0PFLT - I2C1SDA PJ2 K6 - - - - - - - - EPI0S18 - - CCP0 a. The digital signals that are shaded gray are the power-on default values for the corresponding GPIO pin. 9.2 Functional Description Each GPIO port is a separate hardware instantiation of the same physical block (see Figure 9-1 on page 432 and Figure 9-2 on page 433). The LM3S9U90 microcontroller contains nine ports and thus nine of these physical GPIO blocks. Note that not all pins may be implemented on every block. Some GPIO pins can function as I/O signals for the on-chip peripheral modules. For information on which GPIO pins are used for alternate hardware functions, refer to Table 23-5 on page 1181. July 03, 2014 431 Texas Instruments-Production Data General-Purpose Input/Outputs (GPIOs) Figure 9-1. Digital I/O Pads Commit Control GPIOLOCK GPIOCR Port Control GPIOPCTL Mode Control GPIOAFSEL Periph 1 DEMUX Alternate Input Alternate Output Alternate Output Enable MUX Periph 0 Pad Input Periph n GPIO Output GPIO Output Enable Interrupt Control Pad Control GPIOIS GPIOIBE GPIOIEV GPIOIM GPIORIS GPIOMIS GPIOICR GPIODR2R GPIODR4R GPIODR8R GPIOSLR GPIOPUR GPIOPDR GPIOODR GPIODEN MUX GPIODATA GPIODIR Interrupt MUX GPIO Input Data Control Pad Output Digital I/O Pad Package I/O Pin Pad Output Enable Identification Registers GPIOPeriphID0 GPIOPeriphID1 GPIOPeriphID2 GPIOPeriphID3 GPIOPeriphID4 GPIOPeriphID5 GPIOPeriphID6 GPIOPeriphID7 GPIOPCellID0 GPIOPCellID1 GPIOPCellID2 GPIOPCellID3 432 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Figure 9-2. Analog/Digital I/O Pads Commit Control GPIOLOCK GPIOCR Port Control GPIOPCTL Mode Control GPIOAFSEL Periph 1 DEMUX Alternate Input Alternate Output Alternate Output Enable MUX Periph 0 Pad Input Periph n MUX MUX Data Control Pad Output Pad Output Enable Analog/Digital I/O Pad Package I/O Pin GPIO Input GPIO Output GPIODATA GPIODIR Interrupt GPIO Output Enable Interrupt Control GPIOIS GPIOIBE GPIOIEV GPIOIM GPIORIS GPIOMIS GPIOICR Pad Control GPIODR2R GPIODR4R GPIODR8R GPIOSLR GPIOPUR GPIOPDR GPIOODR GPIODEN GPIOAMSEL Analog Circuitry Identification Registers GPIOPeriphID0 GPIOPeriphID1 GPIOPeriphID2 GPIOPeriphID3 9.2.1 GPIOPeriphID4 GPIOPeriphID5 GPIOPeriphID6 GPIOPeriphID7 GPIOPCellID0 GPIOPCellID1 GPIOPCellID2 GPIOPCellID3 ADC (for GPIO pins that connect to the ADC input MUX) Isolation Circuit Data Control The data control registers allow software to configure the operational modes of the GPIOs. The data direction register configures the GPIO as an input or an output while the data register either captures incoming data or drives it out to the pads. Caution – It is possible to create a software sequence that prevents the debugger from connecting to the Stellaris® microcontroller. If the program code loaded into flash immediately changes the JTAG pins to their GPIO functionality, the debugger may not have enough time to connect and halt the controller before the JTAG pin functionality switches. As a result, the debugger may be locked out of the part. This issue can be avoided with a software routine that restores JTAG functionality based on an external or software trigger. 9.2.1.1 Data Direction Operation The GPIO Direction (GPIODIR) register (see page 441) is used to configure each individual pin as an input or output. When the data direction bit is cleared, the GPIO is configured as an input, and the corresponding data register bit captures and stores the value on the GPIO port. When the data direction bit is set, the GPIO is configured as an output, and the corresponding data register bit is driven out on the GPIO port. July 03, 2014 433 Texas Instruments-Production Data General-Purpose Input/Outputs (GPIOs) 9.2.1.2 Data Register Operation To aid in the efficiency of software, the GPIO ports allow for the modification of individual bits in the GPIO Data (GPIODATA) register (see page 440) by using bits [9:2] of the address bus as a mask. In this manner, software drivers can modify individual GPIO pins in a single instruction without affecting the state of the other pins. This method is more efficient than the conventional method of performing a read-modify-write operation to set or clear an individual GPIO pin. To implement this feature, the GPIODATA register covers 256 locations in the memory map. During a write, if the address bit associated with that data bit is set, the value of the GPIODATA register is altered. If the address bit is cleared, the data bit is left unchanged. For example, writing a value of 0xEB to the address GPIODATA + 0x098 has the results shown in Figure 9-3, where u indicates that data is unchanged by the write. Figure 9-3. GPIODATA Write Example ADDR[9:2] 0x098 9 8 7 6 5 4 3 2 1 0 0 0 1 0 0 1 1 0 0 0 0xEB 1 1 1 0 1 0 1 1 GPIODATA u u 1 u u 0 1 u 7 6 5 4 3 2 1 0 During a read, if the address bit associated with the data bit is set, the value is read. If the address bit associated with the data bit is cleared, the data bit is read as a zero, regardless of its actual value. For example, reading address GPIODATA + 0x0C4 yields as shown in Figure 9-4. Figure 9-4. GPIODATA Read Example 9.2.2 ADDR[9:2] 0x0C4 9 8 7 6 5 4 3 2 1 0 0 0 1 1 0 0 0 1 0 0 GPIODATA 1 0 1 1 1 1 1 0 Returned Value 0 0 1 1 0 0 0 0 7 6 5 4 3 2 1 0 Interrupt Control The interrupt capabilities of each GPIO port are controlled by a set of seven registers. These registers are used to select the source of the interrupt, its polarity, and the edge properties. When one or more GPIO inputs cause an interrupt, a single interrupt output is sent to the interrupt controller for the entire GPIO port. For edge-triggered interrupts, software must clear the interrupt to enable any further interrupts. For a level-sensitive interrupt, the external source must hold the level constant for the interrupt to be recognized by the controller. Three registers define the edge or sense that causes interrupts: ■ GPIO Interrupt Sense (GPIOIS) register (see page 442) 434 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller ■ GPIO Interrupt Both Edges (GPIOIBE) register (see page 443) ■ GPIO Interrupt Event (GPIOIEV) register (see page 444) Interrupts are enabled/disabled via the GPIO Interrupt Mask (GPIOIM) register (see page 445). When an interrupt condition occurs, the state of the interrupt signal can be viewed in two locations: the GPIO Raw Interrupt Status (GPIORIS) and GPIO Masked Interrupt Status (GPIOMIS) registers (see page 446 and page 447). As the name implies, the GPIOMIS register only shows interrupt conditions that are allowed to be passed to the interrupt controller. The GPIORIS register indicates that a GPIO pin meets the conditions for an interrupt, but has not necessarily been sent to the interrupt controller. Interrupts are cleared by writing a 1 to the appropriate bit of the GPIO Interrupt Clear (GPIOICR) register (see page 449). When programming the interrupt control registers (GPIOIS, GPIOIBE, or GPIOIEV), the interrupts should be masked (GPIOIM cleared). Writing any value to an interrupt control register can generate a spurious interrupt if the corresponding bits are enabled. 9.2.2.1 ADC Trigger Source In addition to providing GPIO functionality, PB4 can also be used as an external trigger for the ADC. If PB4 is configured as a non-masked interrupt pin (the appropriate bit of GPIOIM is set), an interrupt for Port B is generated, and an external trigger signal is sent to the ADC. If the ADC Event Multiplexer Select (ADCEMUX) register is configured to use the external trigger, an ADC conversion is initiated. See page 662. If no other Port B pins are being used to generate interrupts, the Interrupt 0-31 Set Enable (EN0) register can disable the Port B interrupts, and the ADC interrupt can be used to read back the converted data. Otherwise, the Port B interrupt handler must ignore and clear interrupts on PB4 and wait for the ADC interrupt, or the ADC interrupt must be disabled in the EN0 register and the Port B interrupt handler must poll the ADC registers until the conversion is completed. See page 126 for more information. 9.2.3 Mode Control The GPIO pins can be controlled by either software or hardware. Software control is the default for most signals and corresponds to the GPIO mode, where the GPIODATA register is used to read or write the corresponding pins. When hardware control is enabled via the GPIO Alternate Function Select (GPIOAFSEL) register (see page 450), the pin state is controlled by its alternate function (that is, the peripheral). Further pin muxing options are provided through the GPIO Port Control (GPIOPCTL) register which selects one of several peripheral functions for each GPIO. For information on the configuration options, refer to Table 23-5 on page 1181. Note: 9.2.4 If any pin is to be used as an ADC input, the appropriate bit in the GPIOAMSEL register must be set to disable the analog isolation circuit. Commit Control The GPIO commit control registers provide a layer of protection against accidental programming of critical hardware peripherals. Protection is provided for the NMI pin (PB7) and the four JTAG/SWD pins (PC[3:0]). Writes to protected bits of the GPIO Alternate Function Select (GPIOAFSEL) register (see page 450), GPIO Pull Up Select (GPIOPUR) register (see page 456), GPIO Pull-Down Select (GPIOPDR) register (see page 458), and GPIO Digital Enable (GPIODEN) register (see July 03, 2014 435 Texas Instruments-Production Data General-Purpose Input/Outputs (GPIOs) page 461) are not committed to storage unless the GPIO Lock (GPIOLOCK) register (see page 463) has been unlocked and the appropriate bits of the GPIO Commit (GPIOCR) register (see page 464) have been set. 9.2.5 Pad Control The pad control registers allow software to configure the GPIO pads based on the application requirements. The pad control registers include the GPIODR2R, GPIODR4R, GPIODR8R, GPIOODR, GPIOPUR, GPIOPDR, GPIOSLR, and GPIODEN registers. These registers control drive strength, open-drain configuration, pull-up and pull-down resistors, slew-rate control and digital input enable for each GPIO. 9.2.6 Identification The identification registers configured at reset allow software to detect and identify the module as a GPIO block. The identification registers include the GPIOPeriphID0-GPIOPeriphID7 registers as well as the GPIOPCellID0-GPIOPCellID3 registers. 9.3 Initialization and Configuration The GPIO modules may be accessed via two different memory apertures. The legacy aperture, the Advanced Peripheral Bus (APB), is backwards-compatible with previous Stellaris parts. The other aperture, the Advanced High-Performance Bus (AHB), offers the same register map but provides better back-to-back access performance than the APB bus. These apertures are mutually exclusive. The aperture enabled for a given GPIO port is controlled by the appropriate bit in the GPIOHBCTL register (see page 224). To use the pins in a particular GPIO port, the clock for the port must be enabled by setting the appropriate GPIO Port bit field (GPIOn) in the RCGC2 register (see page 277). When the internal POR signal is asserted and until otherwise configured, all GPIO pins are configured to be undriven (tristate): GPIOAFSEL=0, GPIODEN=0, GPIOPDR=0, and GPIOPUR=0, except for the pins shown in Table 9-1 on page 428. Table 9-4 on page 436 shows all possible configurations of the GPIO pads and the control register settings required to achieve them. Table 9-5 on page 437 shows how a rising edge interrupt is configured for pin 2 of a GPIO port. Table 9-4. GPIO Pad Configuration Examples a Configuration GPIO Register Bit Value AFSEL DIR ODR DEN PUR PDR DR2R DR4R DR8R SLR Digital Input (GPIO) 0 0 0 1 ? ? X X X X Digital Output (GPIO) 0 1 0 1 ? ? ? ? ? ? Open Drain Output (GPIO) 0 1 1 1 X X ? ? ? ? Open Drain Input/Output (I2C) 1 X 1 1 X X ? ? ? ? Digital Input (Timer CCP) 1 X 0 1 ? ? X X X X Digital Output (Timer PWM) 1 X 0 1 ? ? ? ? ? ? Digital Input/Output (SSI) 1 X 0 1 ? ? ? ? ? ? Digital Input/Output (UART) 1 X 0 1 ? ? ? ? ? ? 436 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Table 9-4. GPIO Pad Configuration Examples (continued) a Configuration GPIO Register Bit Value DR2R DR4R DR8R Analog Input (Comparator) AFSEL 0 DIR 0 ODR 0 DEN 0 PUR 0 PDR 0 X X X SLR X Digital Output (Comparator) 1 X 0 1 ? ? ? ? ? ? a. X=Ignored (don’t care bit) ?=Can be either 0 or 1, depending on the configuration Table 9-5. GPIO Interrupt Configuration Example Desired Interrupt Event Trigger Register GPIOIS 0=edge a Pin 2 Bit Value 7 6 5 4 3 2 1 0 X X X X X 0 X X X X X X X 0 X X X X X X X 1 X X 0 0 0 0 0 1 0 0 1=level GPIOIBE 0=single edge 1=both edges GPIOIEV 0=Low level, or falling edge 1=High level, or rising edge GPIOIM 0=masked 1=not masked a. X=Ignored (don’t care bit) 9.4 Register Map Table 9-7 on page 438 lists the GPIO registers. Each GPIO port can be accessed through one of two bus apertures. The legacy aperture, the Advanced Peripheral Bus (APB), is backwards-compatible with previous Stellaris parts. The other aperture, the Advanced High-Performance Bus (AHB), offers the same register map but provides better back-to-back access performance than the APB bus. Important: The GPIO registers in this chapter are duplicated in each GPIO block; however, depending on the block, all eight bits may not be connected to a GPIO pad. In those cases, writing to unconnected bits has no effect, and reading unconnected bits returns no meaningful data. The offset listed is a hexadecimal increment to the register’s address, relative to that GPIO port’s base address: ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ GPIO Port A (APB): 0x4000.4000 GPIO Port A (AHB): 0x4005.8000 GPIO Port B (APB): 0x4000.5000 GPIO Port B (AHB): 0x4005.9000 GPIO Port C (APB): 0x4000.6000 GPIO Port C (AHB): 0x4005.A000 GPIO Port D (APB): 0x4000.7000 GPIO Port D (AHB): 0x4005.B000 GPIO Port E (APB): 0x4002.4000 GPIO Port E (AHB): 0x4005.C000 July 03, 2014 437 Texas Instruments-Production Data General-Purpose Input/Outputs (GPIOs) ■ ■ ■ ■ ■ ■ ■ ■ GPIO Port F (APB): 0x4002.5000 GPIO Port F (AHB): 0x4005.D000 GPIO Port G (APB): 0x4002.6000 GPIO Port G (AHB): 0x4005.E000 GPIO Port H (APB): 0x4002.7000 GPIO Port H (AHB): 0x4005.F000 GPIO Port J (APB): 0x4003.D000 GPIO Port J (AHB): 0x4006.0000 Note that each GPIO module clock must be enabled before the registers can be programmed (see page 277). There must be a delay of 3 system clocks after the GPIO module clock is enabled before any GPIO module registers are accessed. Important: All GPIO pins are configured as GPIOs and tri-stated by default (GPIOAFSEL=0, GPIODEN=0, GPIOPDR=0, GPIOPUR=0, and GPIOPCTL=0, with the exception of the pins shown in the table below. A Power-On-Reset (POR) or asserting RST puts the pins back to their default state. Table 9-6. GPIO Pins With Non-Zero Reset Values GPIO Pins Default State GPIOAFSEL GPIODEN GPIOPDR GPIOPUR GPIOPCTL PA[1:0] UART0 0 0 0 0 0x1 PA[5:2] SSI0 0 0 0 0 0x1 PB[3:2] I2C0 0 0 0 0 0x1 PC[3:0] JTAG/SWD 1 1 0 1 0x3 The default register type for the GPIOCR register is RO for all GPIO pins with the exception of the NMI pin and the four JTAG/SWD pins (PB7 and PC[3:0]). These five pins are the only GPIOs that are protected by the GPIOCR register. Because of this, the register type for GPIO Port B7 and GPIO Port C[3:0] is R/W. The default reset value for the GPIOCR register is 0x0000.00FF for all GPIO pins, with the exception of the NMI pin and the four JTAG/SWD pins (PB7 and PC[3:0]). To ensure that the JTAG port is not accidentally programmed as GPIO pins, the PC[3:0] pins default to non-committable. Similarly, to ensure that the NMI pin is not accidentally programmed as a GPIO pin, the PB7 pin defaults to non-committable. Because of this, the default reset value of GPIOCR for GPIO Port B is 0x0000.007F while the default reset value of GPIOCR for Port C is 0x0000.00F0. Table 9-7. GPIO Register Map Description See page Offset Name Type Reset 0x000 GPIODATA R/W 0x0000.0000 GPIO Data 440 0x400 GPIODIR R/W 0x0000.0000 GPIO Direction 441 0x404 GPIOIS R/W 0x0000.0000 GPIO Interrupt Sense 442 0x408 GPIOIBE R/W 0x0000.0000 GPIO Interrupt Both Edges 443 0x40C GPIOIEV R/W 0x0000.0000 GPIO Interrupt Event 444 0x410 GPIOIM R/W 0x0000.0000 GPIO Interrupt Mask 445 0x414 GPIORIS RO 0x0000.0000 GPIO Raw Interrupt Status 446 438 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Table 9-7. GPIO Register Map (continued) Offset Name 0x418 Reset GPIOMIS RO 0x0000.0000 GPIO Masked Interrupt Status 447 0x41C GPIOICR W1C 0x0000.0000 GPIO Interrupt Clear 449 0x420 GPIOAFSEL R/W - GPIO Alternate Function Select 450 0x500 GPIODR2R R/W 0x0000.00FF GPIO 2-mA Drive Select 452 0x504 GPIODR4R R/W 0x0000.0000 GPIO 4-mA Drive Select 453 0x508 GPIODR8R R/W 0x0000.0000 GPIO 8-mA Drive Select 454 0x50C GPIOODR R/W 0x0000.0000 GPIO Open Drain Select 455 0x510 GPIOPUR R/W - GPIO Pull-Up Select 456 0x514 GPIOPDR R/W 0x0000.0000 GPIO Pull-Down Select 458 0x518 GPIOSLR R/W 0x0000.0000 GPIO Slew Rate Control Select 460 0x51C GPIODEN R/W - GPIO Digital Enable 461 0x520 GPIOLOCK R/W 0x0000.0001 GPIO Lock 463 0x524 GPIOCR - - GPIO Commit 464 0x528 GPIOAMSEL R/W 0x0000.0000 GPIO Analog Mode Select 466 0x52C GPIOPCTL R/W - GPIO Port Control 468 0xFD0 GPIOPeriphID4 RO 0x0000.0000 GPIO Peripheral Identification 4 470 0xFD4 GPIOPeriphID5 RO 0x0000.0000 GPIO Peripheral Identification 5 471 0xFD8 GPIOPeriphID6 RO 0x0000.0000 GPIO Peripheral Identification 6 472 0xFDC GPIOPeriphID7 RO 0x0000.0000 GPIO Peripheral Identification 7 473 0xFE0 GPIOPeriphID0 RO 0x0000.0061 GPIO Peripheral Identification 0 474 0xFE4 GPIOPeriphID1 RO 0x0000.0000 GPIO Peripheral Identification 1 475 0xFE8 GPIOPeriphID2 RO 0x0000.0018 GPIO Peripheral Identification 2 476 0xFEC GPIOPeriphID3 RO 0x0000.0001 GPIO Peripheral Identification 3 477 0xFF0 GPIOPCellID0 RO 0x0000.000D GPIO PrimeCell Identification 0 478 0xFF4 GPIOPCellID1 RO 0x0000.00F0 GPIO PrimeCell Identification 1 479 0xFF8 GPIOPCellID2 RO 0x0000.0005 GPIO PrimeCell Identification 2 480 0xFFC GPIOPCellID3 RO 0x0000.00B1 GPIO PrimeCell Identification 3 481 9.5 Description See page Type Register Descriptions The remainder of this section lists and describes the GPIO registers, in numerical order by address offset. July 03, 2014 439 Texas Instruments-Production Data General-Purpose Input/Outputs (GPIOs) Register 1: GPIO Data (GPIODATA), offset 0x000 The GPIODATA register is the data register. In software control mode, values written in the GPIODATA register are transferred onto the GPIO port pins if the respective pins have been configured as outputs through the GPIO Direction (GPIODIR) register (see page 441). In order to write to GPIODATA, the corresponding bits in the mask, resulting from the address bus bits [9:2], must be set. Otherwise, the bit values remain unchanged by the write. Similarly, the values read from this register are determined for each bit by the mask bit derived from the address used to access the data register, bits [9:2]. Bits that are set in the address mask cause the corresponding bits in GPIODATA to be read, and bits that are clear in the address mask cause the corresponding bits in GPIODATA to be read as 0, regardless of their value. A read from GPIODATA returns the last bit value written if the respective pins are configured as outputs, or it returns the value on the corresponding input pin when these are configured as inputs. All bits are cleared by a reset. GPIO Data (GPIODATA) GPIO Port A (APB) base: 0x4000.4000 GPIO Port A (AHB) base: 0x4005.8000 GPIO Port B (APB) base: 0x4000.5000 GPIO Port B (AHB) base: 0x4005.9000 GPIO Port C (APB) base: 0x4000.6000 GPIO Port C (AHB) base: 0x4005.A000 GPIO Port D (APB) base: 0x4000.7000 GPIO Port D (AHB) base: 0x4005.B000 GPIO Port E (APB) base: 0x4002.4000 GPIO Port E (AHB) base: 0x4005.C000 GPIO Port F (APB) base: 0x4002.5000 GPIO Port F (AHB) base: 0x4005.D000 GPIO Port G (APB) base: 0x4002.6000 GPIO Port G (AHB) base: 0x4005.E000 GPIO Port H (APB) base: 0x4002.7000 GPIO Port H (AHB) base: 0x4005.F000 GPIO Port J (APB) base: 0x4003.D000 GPIO Port J (AHB) base: 0x4006.0000 Offset 0x000 Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 8 7 6 5 4 3 2 1 0 RO 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 reserved Type Reset reserved Type Reset DATA RO 0 Bit/Field Name Type Reset 31:8 reserved RO 0x0000.00 7:0 DATA R/W 0x00 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. GPIO Data This register is virtually mapped to 256 locations in the address space. To facilitate the reading and writing of data to these registers by independent drivers, the data read from and written to the registers are masked by the eight address lines [9:2]. Reads from this register return its current state. Writes to this register only affect bits that are not masked by ADDR[9:2] and are configured as outputs. See “Data Register Operation” on page 434 for examples of reads and writes. 440 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 2: GPIO Direction (GPIODIR), offset 0x400 The GPIODIR register is the data direction register. Setting a bit in the GPIODIR register configures the corresponding pin to be an output, while clearing a bit configures the corresponding pin to be an input. All bits are cleared by a reset, meaning all GPIO pins are inputs by default. GPIO Direction (GPIODIR) GPIO Port A (APB) base: 0x4000.4000 GPIO Port A (AHB) base: 0x4005.8000 GPIO Port B (APB) base: 0x4000.5000 GPIO Port B (AHB) base: 0x4005.9000 GPIO Port C (APB) base: 0x4000.6000 GPIO Port C (AHB) base: 0x4005.A000 GPIO Port D (APB) base: 0x4000.7000 GPIO Port D (AHB) base: 0x4005.B000 GPIO Port E (APB) base: 0x4002.4000 GPIO Port E (AHB) base: 0x4005.C000 GPIO Port F (APB) base: 0x4002.5000 GPIO Port F (AHB) base: 0x4005.D000 GPIO Port G (APB) base: 0x4002.6000 GPIO Port G (AHB) base: 0x4005.E000 GPIO Port H (APB) base: 0x4002.7000 GPIO Port H (AHB) base: 0x4005.F000 GPIO Port J (APB) base: 0x4003.D000 GPIO Port J (AHB) base: 0x4006.0000 Offset 0x400 Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 3 2 1 0 R/W 0 R/W 0 R/W 0 R/W 0 reserved Type Reset RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 8 7 6 5 4 reserved Type Reset RO 0 RO 0 RO 0 RO 0 DIR RO 0 RO 0 RO 0 Bit/Field Name Type Reset 31:8 reserved RO 0x0000.00 7:0 DIR R/W 0x00 RO 0 R/W 0 R/W 0 R/W 0 R/W 0 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. GPIO Data Direction Value Description 0 Corresponding pin is an input. 1 Corresponding pins is an output. July 03, 2014 441 Texas Instruments-Production Data General-Purpose Input/Outputs (GPIOs) Register 3: GPIO Interrupt Sense (GPIOIS), offset 0x404 The GPIOIS register is the interrupt sense register. Setting a bit in the GPIOIS register configures the corresponding pin to detect levels, while clearing a bit configures the corresponding pin to detect edges. All bits are cleared by a reset. GPIO Interrupt Sense (GPIOIS) GPIO Port A (APB) base: 0x4000.4000 GPIO Port A (AHB) base: 0x4005.8000 GPIO Port B (APB) base: 0x4000.5000 GPIO Port B (AHB) base: 0x4005.9000 GPIO Port C (APB) base: 0x4000.6000 GPIO Port C (AHB) base: 0x4005.A000 GPIO Port D (APB) base: 0x4000.7000 GPIO Port D (AHB) base: 0x4005.B000 GPIO Port E (APB) base: 0x4002.4000 GPIO Port E (AHB) base: 0x4005.C000 GPIO Port F (APB) base: 0x4002.5000 GPIO Port F (AHB) base: 0x4005.D000 GPIO Port G (APB) base: 0x4002.6000 GPIO Port G (AHB) base: 0x4005.E000 GPIO Port H (APB) base: 0x4002.7000 GPIO Port H (AHB) base: 0x4005.F000 GPIO Port J (APB) base: 0x4003.D000 GPIO Port J (AHB) base: 0x4006.0000 Offset 0x404 Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 3 2 1 0 R/W 0 R/W 0 R/W 0 R/W 0 reserved Type Reset RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 8 7 6 5 4 reserved Type Reset RO 0 RO 0 RO 0 RO 0 IS RO 0 RO 0 RO 0 Bit/Field Name Type Reset 31:8 reserved RO 0x0000.00 7:0 IS R/W 0x00 RO 0 R/W 0 R/W 0 R/W 0 R/W 0 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. GPIO Interrupt Sense Value Description 0 The edge on the corresponding pin is detected (edge-sensitive). 1 The level on the corresponding pin is detected (level-sensitive). 442 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 4: GPIO Interrupt Both Edges (GPIOIBE), offset 0x408 The GPIOIBE register allows both edges to cause interrupts. When the corresponding bit in the GPIO Interrupt Sense (GPIOIS) register (see page 442) is set to detect edges, setting a bit in the GPIOIBE register configures the corresponding pin to detect both rising and falling edges, regardless of the corresponding bit in the GPIO Interrupt Event (GPIOIEV) register (see page 444). Clearing a bit configures the pin to be controlled by the GPIOIEV register. All bits are cleared by a reset. GPIO Interrupt Both Edges (GPIOIBE) GPIO Port A (APB) base: 0x4000.4000 GPIO Port A (AHB) base: 0x4005.8000 GPIO Port B (APB) base: 0x4000.5000 GPIO Port B (AHB) base: 0x4005.9000 GPIO Port C (APB) base: 0x4000.6000 GPIO Port C (AHB) base: 0x4005.A000 GPIO Port D (APB) base: 0x4000.7000 GPIO Port D (AHB) base: 0x4005.B000 GPIO Port E (APB) base: 0x4002.4000 GPIO Port E (AHB) base: 0x4005.C000 GPIO Port F (APB) base: 0x4002.5000 GPIO Port F (AHB) base: 0x4005.D000 GPIO Port G (APB) base: 0x4002.6000 GPIO Port G (AHB) base: 0x4005.E000 GPIO Port H (APB) base: 0x4002.7000 GPIO Port H (AHB) base: 0x4005.F000 GPIO Port J (APB) base: 0x4003.D000 GPIO Port J (AHB) base: 0x4006.0000 Offset 0x408 Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 3 2 1 0 R/W 0 R/W 0 R/W 0 R/W 0 reserved Type Reset RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 8 7 6 5 4 reserved Type Reset RO 0 RO 0 RO 0 RO 0 IBE RO 0 RO 0 RO 0 Bit/Field Name Type Reset 31:8 reserved RO 0x0000.00 7:0 IBE R/W 0x00 RO 0 R/W 0 R/W 0 R/W 0 R/W 0 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. GPIO Interrupt Both Edges Value Description 0 Interrupt generation is controlled by the GPIO Interrupt Event (GPIOIEV) register (see page 444). 1 Both edges on the corresponding pin trigger an interrupt. July 03, 2014 443 Texas Instruments-Production Data General-Purpose Input/Outputs (GPIOs) Register 5: GPIO Interrupt Event (GPIOIEV), offset 0x40C The GPIOIEV register is the interrupt event register. Setting a bit in the GPIOIEV register configures the corresponding pin to detect rising edges or high levels, depending on the corresponding bit value in the GPIO Interrupt Sense (GPIOIS) register (see page 442). Clearing a bit configures the pin to detect falling edges or low levels, depending on the corresponding bit value in the GPIOIS register. All bits are cleared by a reset. GPIO Interrupt Event (GPIOIEV) GPIO Port A (APB) base: 0x4000.4000 GPIO Port A (AHB) base: 0x4005.8000 GPIO Port B (APB) base: 0x4000.5000 GPIO Port B (AHB) base: 0x4005.9000 GPIO Port C (APB) base: 0x4000.6000 GPIO Port C (AHB) base: 0x4005.A000 GPIO Port D (APB) base: 0x4000.7000 GPIO Port D (AHB) base: 0x4005.B000 GPIO Port E (APB) base: 0x4002.4000 GPIO Port E (AHB) base: 0x4005.C000 GPIO Port F (APB) base: 0x4002.5000 GPIO Port F (AHB) base: 0x4005.D000 GPIO Port G (APB) base: 0x4002.6000 GPIO Port G (AHB) base: 0x4005.E000 GPIO Port H (APB) base: 0x4002.7000 GPIO Port H (AHB) base: 0x4005.F000 GPIO Port J (APB) base: 0x4003.D000 GPIO Port J (AHB) base: 0x4006.0000 Offset 0x40C Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 3 2 1 0 R/W 0 R/W 0 R/W 0 R/W 0 reserved Type Reset RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 8 7 6 5 4 reserved Type Reset RO 0 RO 0 RO 0 RO 0 IEV RO 0 RO 0 RO 0 Bit/Field Name Type Reset 31:8 reserved RO 0x0000.00 7:0 IEV R/W 0x00 RO 0 R/W 0 R/W 0 R/W 0 R/W 0 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. GPIO Interrupt Event Value Description 0 A falling edge or a Low level on the corresponding pin triggers an interrupt. 1 A rising edge or a High level on the corresponding pin triggers an interrupt. 444 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 6: GPIO Interrupt Mask (GPIOIM), offset 0x410 The GPIOIM register is the interrupt mask register. Setting a bit in the GPIOIM register allows interrupts that are generated by the corresponding pin to be sent to the interrupt controller on the combined interrupt signal. Clearing a bit prevents an interrupt on the corresponding pin from being sent to the interrupt controller. All bits are cleared by a reset. GPIO Interrupt Mask (GPIOIM) GPIO Port A (APB) base: 0x4000.4000 GPIO Port A (AHB) base: 0x4005.8000 GPIO Port B (APB) base: 0x4000.5000 GPIO Port B (AHB) base: 0x4005.9000 GPIO Port C (APB) base: 0x4000.6000 GPIO Port C (AHB) base: 0x4005.A000 GPIO Port D (APB) base: 0x4000.7000 GPIO Port D (AHB) base: 0x4005.B000 GPIO Port E (APB) base: 0x4002.4000 GPIO Port E (AHB) base: 0x4005.C000 GPIO Port F (APB) base: 0x4002.5000 GPIO Port F (AHB) base: 0x4005.D000 GPIO Port G (APB) base: 0x4002.6000 GPIO Port G (AHB) base: 0x4005.E000 GPIO Port H (APB) base: 0x4002.7000 GPIO Port H (AHB) base: 0x4005.F000 GPIO Port J (APB) base: 0x4003.D000 GPIO Port J (AHB) base: 0x4006.0000 Offset 0x410 Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 3 2 1 0 R/W 0 R/W 0 R/W 0 R/W 0 reserved Type Reset RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 8 7 6 5 4 reserved Type Reset RO 0 RO 0 RO 0 RO 0 IME RO 0 RO 0 RO 0 Bit/Field Name Type Reset 31:8 reserved RO 0 7:0 IME R/W 0x00 RO 0 R/W 0 R/W 0 R/W 0 R/W 0 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. GPIO Interrupt Mask Enable Value Description 0 The interrupt from the corresponding pin is masked. 1 The interrupt from the corresponding pin is sent to the interrupt controller. July 03, 2014 445 Texas Instruments-Production Data General-Purpose Input/Outputs (GPIOs) Register 7: GPIO Raw Interrupt Status (GPIORIS), offset 0x414 The GPIORIS register is the raw interrupt status register. A bit in this register is set when an interrupt condition occurs on the corresponding GPIO pin. If the corresponding bit in the GPIO Interrupt Mask (GPIOIM) register (see page 445) is set, the interrupt is sent to the interrupt controller. Bits read as zero indicate that corresponding input pins have not initiated an interrupt. A bit in this register can be cleared by writing a 1 to the corresponding bit in the GPIO Interrupt Clear (GPIOICR) register. GPIO Raw Interrupt Status (GPIORIS) GPIO Port A (APB) base: 0x4000.4000 GPIO Port A (AHB) base: 0x4005.8000 GPIO Port B (APB) base: 0x4000.5000 GPIO Port B (AHB) base: 0x4005.9000 GPIO Port C (APB) base: 0x4000.6000 GPIO Port C (AHB) base: 0x4005.A000 GPIO Port D (APB) base: 0x4000.7000 GPIO Port D (AHB) base: 0x4005.B000 GPIO Port E (APB) base: 0x4002.4000 GPIO Port E (AHB) base: 0x4005.C000 GPIO Port F (APB) base: 0x4002.5000 GPIO Port F (AHB) base: 0x4005.D000 GPIO Port G (APB) base: 0x4002.6000 GPIO Port G (AHB) base: 0x4005.E000 GPIO Port H (APB) base: 0x4002.7000 GPIO Port H (AHB) base: 0x4005.F000 GPIO Port J (APB) base: 0x4003.D000 GPIO Port J (AHB) base: 0x4006.0000 Offset 0x414 Type RO, reset 0x0000.0000 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 3 2 1 0 RO 0 RO 0 RO 0 RO 0 reserved Type Reset RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 8 7 6 5 4 reserved Type Reset RO 0 RO 0 RO 0 RO 0 RIS RO 0 RO 0 RO 0 Bit/Field Name Type Reset 31:8 reserved RO 0 7:0 RIS RO 0x00 RO 0 RO 0 RO 0 RO 0 RO 0 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. GPIO Interrupt Raw Status Value Description 1 An interrupt condition has occurred on the corresponding pin. 0 An interrupt condition has not occurred on the corresponding pin. A bit is cleared by writing a 1 to the corresponding bit in the GPIOICR register. 446 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 8: GPIO Masked Interrupt Status (GPIOMIS), offset 0x418 The GPIOMIS register is the masked interrupt status register. If a bit is set in this register, the corresponding interrupt has triggered an interrupt to the interrupt controller. If a bit is clear, either no interrupt has been generated, or the interrupt is masked. In addition to providing GPIO functionality, PB4 can also be used as an external trigger for the ADC. If PB4 is configured as a non-masked interrupt pin (the appropriate bit of GPIOIM is set), an interrupt for Port B is generated, and an external trigger signal is sent to the ADC. If the ADC Event Multiplexer Select (ADCEMUX) register is configured to use the external trigger, an ADC conversion is initiated. See page 662. If no other Port B pins are being used to generate interrupts, the Interrupt 0-31 Set Enable (EN0) register can disable the Port B interrupts, and the ADC interrupt can be used to read back the converted data. Otherwise, the Port B interrupt handler must ignore and clear interrupts on PB4 and wait for the ADC interrupt, or the ADC interrupt must be disabled in the EN0 register and the Port B interrupt handler must poll the ADC registers until the conversion is completed. See page 126 for more information. GPIOMIS is the state of the interrupt after masking. GPIO Masked Interrupt Status (GPIOMIS) GPIO Port A (APB) base: 0x4000.4000 GPIO Port A (AHB) base: 0x4005.8000 GPIO Port B (APB) base: 0x4000.5000 GPIO Port B (AHB) base: 0x4005.9000 GPIO Port C (APB) base: 0x4000.6000 GPIO Port C (AHB) base: 0x4005.A000 GPIO Port D (APB) base: 0x4000.7000 GPIO Port D (AHB) base: 0x4005.B000 GPIO Port E (APB) base: 0x4002.4000 GPIO Port E (AHB) base: 0x4005.C000 GPIO Port F (APB) base: 0x4002.5000 GPIO Port F (AHB) base: 0x4005.D000 GPIO Port G (APB) base: 0x4002.6000 GPIO Port G (AHB) base: 0x4005.E000 GPIO Port H (APB) base: 0x4002.7000 GPIO Port H (AHB) base: 0x4005.F000 GPIO Port J (APB) base: 0x4003.D000 GPIO Port J (AHB) base: 0x4006.0000 Offset 0x418 Type RO, reset 0x0000.0000 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 3 2 1 0 RO 0 RO 0 RO 0 RO 0 reserved Type Reset RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 8 7 6 5 4 reserved Type Reset RO 0 RO 0 RO 0 RO 0 MIS RO 0 RO 0 RO 0 Bit/Field Name Type Reset 31:8 reserved RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. July 03, 2014 447 Texas Instruments-Production Data General-Purpose Input/Outputs (GPIOs) Bit/Field Name Type Reset Description 7:0 MIS RO 0x00 GPIO Masked Interrupt Status Value Description 1 An interrupt condition on the corresponding pin has triggered an interrupt to the interrupt controller. 0 An interrupt condition on the corresponding pin is masked or has not occurred. A bit is cleared by writing a 1 to the corresponding bit in the GPIOICR register. 448 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 9: GPIO Interrupt Clear (GPIOICR), offset 0x41C The GPIOICR register is the interrupt clear register. Writing a 1 to a bit in this register clears the corresponding interrupt bit in the GPIORIS and GPIOMIS registers. Writing a 0 has no effect. GPIO Interrupt Clear (GPIOICR) GPIO Port A (APB) base: 0x4000.4000 GPIO Port A (AHB) base: 0x4005.8000 GPIO Port B (APB) base: 0x4000.5000 GPIO Port B (AHB) base: 0x4005.9000 GPIO Port C (APB) base: 0x4000.6000 GPIO Port C (AHB) base: 0x4005.A000 GPIO Port D (APB) base: 0x4000.7000 GPIO Port D (AHB) base: 0x4005.B000 GPIO Port E (APB) base: 0x4002.4000 GPIO Port E (AHB) base: 0x4005.C000 GPIO Port F (APB) base: 0x4002.5000 GPIO Port F (AHB) base: 0x4005.D000 GPIO Port G (APB) base: 0x4002.6000 GPIO Port G (AHB) base: 0x4005.E000 GPIO Port H (APB) base: 0x4002.7000 GPIO Port H (AHB) base: 0x4005.F000 GPIO Port J (APB) base: 0x4003.D000 GPIO Port J (AHB) base: 0x4006.0000 Offset 0x41C Type W1C, reset 0x0000.0000 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 3 2 1 0 W1C 0 W1C 0 W1C 0 W1C 0 reserved Type Reset RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 8 7 6 5 4 reserved Type Reset RO 0 RO 0 RO 0 RO 0 IC RO 0 RO 0 RO 0 Bit/Field Name Type Reset 31:8 reserved RO 0 7:0 IC W1C 0x00 RO 0 W1C 0 W1C 0 W1C 0 W1C 0 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. GPIO Interrupt Clear Value Description 1 The corresponding interrupt is cleared. 0 The corresponding interrupt is unaffected. July 03, 2014 449 Texas Instruments-Production Data General-Purpose Input/Outputs (GPIOs) Register 10: GPIO Alternate Function Select (GPIOAFSEL), offset 0x420 The GPIOAFSEL register is the mode control select register. If a bit is clear, the pin is used as a GPIO and is controlled by the GPIO registers. Setting a bit in this register configures the corresponding GPIO line to be controlled by an associated peripheral. Several possible peripheral functions are multiplexed on each GPIO. The GPIO Port Control (GPIOPCTL) register is used to select one of the possible functions. Table 23-5 on page 1181 details which functions are muxed on each GPIO pin. The reset value for this register is 0x0000.0000 for GPIO ports that are not listed in the table below. Important: All GPIO pins are configured as GPIOs and tri-stated by default (GPIOAFSEL=0, GPIODEN=0, GPIOPDR=0, GPIOPUR=0, and GPIOPCTL=0, with the exception of the pins shown in the table below. A Power-On-Reset (POR) or asserting RST puts the pins back to their default state. Table 9-8. GPIO Pins With Non-Zero Reset Values GPIO Pins Default State PA[1:0] UART0 GPIOAFSEL GPIODEN GPIOPDR GPIOPUR 0 0 0 0 GPIOPCTL 0x1 PA[5:2] SSI0 0 0 0 0 0x1 PB[3:2] I2C0 0 0 0 0 0x1 PC[3:0] JTAG/SWD 1 1 0 1 0x3 Caution – It is possible to create a software sequence that prevents the debugger from connecting to the Stellaris microcontroller. If the program code loaded into flash immediately changes the JTAG pins to their GPIO functionality, the debugger may not have enough time to connect and halt the controller before the JTAG pin functionality switches. As a result, the debugger may be locked out of the part. This issue can be avoided with a software routine that restores JTAG functionality based on an external or software trigger. The GPIO commit control registers provide a layer of protection against accidental programming of critical hardware peripherals. Protection is provided for the NMI pin (PB7) and the four JTAG/SWD pins (PC[3:0]). Writes to protected bits of the GPIO Alternate Function Select (GPIOAFSEL) register (see page 450), GPIO Pull Up Select (GPIOPUR) register (see page 456), GPIO Pull-Down Select (GPIOPDR) register (see page 458), and GPIO Digital Enable (GPIODEN) register (see page 461) are not committed to storage unless the GPIO Lock (GPIOLOCK) register (see page 463) has been unlocked and the appropriate bits of the GPIO Commit (GPIOCR) register (see page 464) have been set. When using the I2C module, in addition to setting the GPIOAFSEL register bits for the I2C clock and data pins, the data pins should be set to open drain using the GPIO Open Drain Select (GPIOODR) register (see examples in “Initialization and Configuration” on page 436). 450 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller GPIO Alternate Function Select (GPIOAFSEL) GPIO Port A (APB) base: 0x4000.4000 GPIO Port A (AHB) base: 0x4005.8000 GPIO Port B (APB) base: 0x4000.5000 GPIO Port B (AHB) base: 0x4005.9000 GPIO Port C (APB) base: 0x4000.6000 GPIO Port C (AHB) base: 0x4005.A000 GPIO Port D (APB) base: 0x4000.7000 GPIO Port D (AHB) base: 0x4005.B000 GPIO Port E (APB) base: 0x4002.4000 GPIO Port E (AHB) base: 0x4005.C000 GPIO Port F (APB) base: 0x4002.5000 GPIO Port F (AHB) base: 0x4005.D000 GPIO Port G (APB) base: 0x4002.6000 GPIO Port G (AHB) base: 0x4005.E000 GPIO Port H (APB) base: 0x4002.7000 GPIO Port H (AHB) base: 0x4005.F000 GPIO Port J (APB) base: 0x4003.D000 GPIO Port J (AHB) base: 0x4006.0000 Offset 0x420 Type R/W, reset 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 3 2 1 0 R/W - R/W - R/W - R/W - reserved Type Reset RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 8 7 6 5 4 reserved Type Reset RO 0 RO 0 RO 0 RO 0 AFSEL RO 0 RO 0 RO 0 Bit/Field Name Type Reset 31:8 reserved RO 0x0000.00 7:0 AFSEL R/W - RO 0 R/W - R/W - R/W - R/W - Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. GPIO Alternate Function Select Value Description 0 The associated pin functions as a GPIO and is controlled by the GPIO registers. 1 The associated pin functions as a peripheral signal and is controlled by the alternate hardware function. The reset value for this register is 0x0000.0000 for GPIO ports that are not listed in Table 9-1 on page 428. July 03, 2014 451 Texas Instruments-Production Data General-Purpose Input/Outputs (GPIOs) Register 11: GPIO 2-mA Drive Select (GPIODR2R), offset 0x500 The GPIODR2R register is the 2-mA drive control register. Each GPIO signal in the port can be individually configured without affecting the other pads. When setting the DRV2 bit for a GPIO signal, the corresponding DRV4 bit in the GPIODR4R register and DRV8 bit in the GPIODR8R register are automatically cleared by hardware. By default, all GPIO pins have 2-mA drive. GPIO 2-mA Drive Select (GPIODR2R) GPIO Port A (APB) base: 0x4000.4000 GPIO Port A (AHB) base: 0x4005.8000 GPIO Port B (APB) base: 0x4000.5000 GPIO Port B (AHB) base: 0x4005.9000 GPIO Port C (APB) base: 0x4000.6000 GPIO Port C (AHB) base: 0x4005.A000 GPIO Port D (APB) base: 0x4000.7000 GPIO Port D (AHB) base: 0x4005.B000 GPIO Port E (APB) base: 0x4002.4000 GPIO Port E (AHB) base: 0x4005.C000 GPIO Port F (APB) base: 0x4002.5000 GPIO Port F (AHB) base: 0x4005.D000 GPIO Port G (APB) base: 0x4002.6000 GPIO Port G (AHB) base: 0x4005.E000 GPIO Port H (APB) base: 0x4002.7000 GPIO Port H (AHB) base: 0x4005.F000 GPIO Port J (APB) base: 0x4003.D000 GPIO Port J (AHB) base: 0x4006.0000 Offset 0x500 Type R/W, reset 0x0000.00FF 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 3 2 1 0 R/W 1 R/W 1 R/W 1 R/W 1 reserved Type Reset RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 8 7 6 5 4 reserved Type Reset RO 0 RO 0 RO 0 RO 0 DRV2 RO 0 RO 0 RO 0 Bit/Field Name Type Reset 31:8 reserved RO 0x0000.00 7:0 DRV2 R/W 0xFF RO 0 R/W 1 R/W 1 R/W 1 R/W 1 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. Output Pad 2-mA Drive Enable Value Description 1 The corresponding GPIO pin has 2-mA drive. 0 The drive for the corresponding GPIO pin is controlled by the GPIODR4R or GPIODR8R register. Setting a bit in either the GPIODR4 register or the GPIODR8 register clears the corresponding 2-mA enable bit. The change is effective on the second clock cycle after the write if accessing GPIO via the APB memory aperture. If using AHB access, the change is effective on the next clock cycle. 452 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 12: GPIO 4-mA Drive Select (GPIODR4R), offset 0x504 The GPIODR4R register is the 4-mA drive control register. Each GPIO signal in the port can be individually configured without affecting the other pads. When setting the DRV4 bit for a GPIO signal, the corresponding DRV2 bit in the GPIODR2R register and DRV8 bit in the GPIODR8R register are automatically cleared by hardware. GPIO 4-mA Drive Select (GPIODR4R) GPIO Port A (APB) base: 0x4000.4000 GPIO Port A (AHB) base: 0x4005.8000 GPIO Port B (APB) base: 0x4000.5000 GPIO Port B (AHB) base: 0x4005.9000 GPIO Port C (APB) base: 0x4000.6000 GPIO Port C (AHB) base: 0x4005.A000 GPIO Port D (APB) base: 0x4000.7000 GPIO Port D (AHB) base: 0x4005.B000 GPIO Port E (APB) base: 0x4002.4000 GPIO Port E (AHB) base: 0x4005.C000 GPIO Port F (APB) base: 0x4002.5000 GPIO Port F (AHB) base: 0x4005.D000 GPIO Port G (APB) base: 0x4002.6000 GPIO Port G (AHB) base: 0x4005.E000 GPIO Port H (APB) base: 0x4002.7000 GPIO Port H (AHB) base: 0x4005.F000 GPIO Port J (APB) base: 0x4003.D000 GPIO Port J (AHB) base: 0x4006.0000 Offset 0x504 Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 3 2 1 0 R/W 0 R/W 0 R/W 0 R/W 0 reserved Type Reset RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 8 7 6 5 4 reserved Type Reset RO 0 RO 0 RO 0 RO 0 DRV4 RO 0 RO 0 RO 0 Bit/Field Name Type Reset 31:8 reserved RO 0x0000.00 7:0 DRV4 R/W 0x00 RO 0 R/W 0 R/W 0 R/W 0 R/W 0 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. Output Pad 4-mA Drive Enable Value Description 1 The corresponding GPIO pin has 4-mA drive. 0 The drive for the corresponding GPIO pin is controlled by the GPIODR2R or GPIODR8R register. Setting a bit in either the GPIODR2 register or the GPIODR8 register clears the corresponding 4-mA enable bit. The change is effective on the second clock cycle after the write if accessing GPIO via the APB memory aperture. If using AHB access, the change is effective on the next clock cycle. July 03, 2014 453 Texas Instruments-Production Data General-Purpose Input/Outputs (GPIOs) Register 13: GPIO 8-mA Drive Select (GPIODR8R), offset 0x508 The GPIODR8R register is the 8-mA drive control register. Each GPIO signal in the port can be individually configured without affecting the other pads. When setting the DRV8 bit for a GPIO signal, the corresponding DRV2 bit in the GPIODR2R register and DRV4 bit in the GPIODR4R register are automatically cleared by hardware. The 8-mA setting is also used for high-current operation. Note: There is no configuration difference between 8-mA and high-current operation. The additional current capacity results from a shift in the VOH/VOL levels. See “Recommended Operating Conditions” on page 1222 for further information. GPIO 8-mA Drive Select (GPIODR8R) GPIO Port A (APB) base: 0x4000.4000 GPIO Port A (AHB) base: 0x4005.8000 GPIO Port B (APB) base: 0x4000.5000 GPIO Port B (AHB) base: 0x4005.9000 GPIO Port C (APB) base: 0x4000.6000 GPIO Port C (AHB) base: 0x4005.A000 GPIO Port D (APB) base: 0x4000.7000 GPIO Port D (AHB) base: 0x4005.B000 GPIO Port E (APB) base: 0x4002.4000 GPIO Port E (AHB) base: 0x4005.C000 GPIO Port F (APB) base: 0x4002.5000 GPIO Port F (AHB) base: 0x4005.D000 GPIO Port G (APB) base: 0x4002.6000 GPIO Port G (AHB) base: 0x4005.E000 GPIO Port H (APB) base: 0x4002.7000 GPIO Port H (AHB) base: 0x4005.F000 GPIO Port J (APB) base: 0x4003.D000 GPIO Port J (AHB) base: 0x4006.0000 Offset 0x508 Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 3 2 1 0 R/W 0 R/W 0 R/W 0 R/W 0 reserved Type Reset RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 8 7 6 5 4 reserved Type Reset RO 0 RO 0 RO 0 RO 0 DRV8 RO 0 RO 0 RO 0 Bit/Field Name Type Reset 31:8 reserved RO 0x0000.00 7:0 DRV8 R/W 0x00 RO 0 R/W 0 R/W 0 R/W 0 R/W 0 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. Output Pad 8-mA Drive Enable Value Description 1 The corresponding GPIO pin has 8-mA drive. 0 The drive for the corresponding GPIO pin is controlled by the GPIODR2R or GPIODR4R register. Setting a bit in either the GPIODR2 register or the GPIODR4 register clears the corresponding 8-mA enable bit. The change is effective on the second clock cycle after the write if accessing GPIO via the APB memory aperture. If using AHB access, the change is effective on the next clock cycle. 454 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 14: GPIO Open Drain Select (GPIOODR), offset 0x50C The GPIOODR register is the open drain control register. Setting a bit in this register enables the open-drain configuration of the corresponding GPIO pad. When open-drain mode is enabled, the corresponding bit should also be set in the GPIO Digital Enable (GPIODEN) register (see page 461). Corresponding bits in the drive strength and slew rate control registers (GPIODR2R, GPIODR4R, GPIODR8R, and GPIOSLR) can be set to achieve the desired rise and fall times. The GPIO acts as an input if the corresponding bit in the GPIODIR register is cleared. If open drain is selected while the GPIO is configured as an input, the GPIO will remain an input and the open-drain selection has no effect until the GPIO is changed to an output. When using the I2C module, in addition to configuring the pin to open drain, the GPIO Alternate Function Select (GPIOAFSEL) register bits for the I2C clock and data pins should be set (see examples in “Initialization and Configuration” on page 436). GPIO Open Drain Select (GPIOODR) GPIO Port A (APB) base: 0x4000.4000 GPIO Port A (AHB) base: 0x4005.8000 GPIO Port B (APB) base: 0x4000.5000 GPIO Port B (AHB) base: 0x4005.9000 GPIO Port C (APB) base: 0x4000.6000 GPIO Port C (AHB) base: 0x4005.A000 GPIO Port D (APB) base: 0x4000.7000 GPIO Port D (AHB) base: 0x4005.B000 GPIO Port E (APB) base: 0x4002.4000 GPIO Port E (AHB) base: 0x4005.C000 GPIO Port F (APB) base: 0x4002.5000 GPIO Port F (AHB) base: 0x4005.D000 GPIO Port G (APB) base: 0x4002.6000 GPIO Port G (AHB) base: 0x4005.E000 GPIO Port H (APB) base: 0x4002.7000 GPIO Port H (AHB) base: 0x4005.F000 GPIO Port J (APB) base: 0x4003.D000 GPIO Port J (AHB) base: 0x4006.0000 Offset 0x50C Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 3 2 1 0 R/W 0 R/W 0 R/W 0 R/W 0 reserved Type Reset RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 8 7 6 5 4 reserved Type Reset RO 0 RO 0 RO 0 RO 0 ODE RO 0 RO 0 RO 0 Bit/Field Name Type Reset 31:8 reserved RO 0x0000.00 7:0 ODE R/W 0x00 RO 0 R/W 0 R/W 0 R/W 0 R/W 0 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. Output Pad Open Drain Enable Value Description 1 The corresponding pin is configured as open drain. 0 The corresponding pin is not configured as open drain. July 03, 2014 455 Texas Instruments-Production Data General-Purpose Input/Outputs (GPIOs) Register 15: GPIO Pull-Up Select (GPIOPUR), offset 0x510 The GPIOPUR register is the pull-up control register. When a bit is set, a weak pull-up resistor on the corresponding GPIO signal is enabled. Setting a bit in GPIOPUR automatically clears the corresponding bit in the GPIO Pull-Down Select (GPIOPDR) register (see page 458). Write access to this register is protected with the GPIOCR register. Bits in GPIOCR that are cleared prevent writes to the equivalent bit in this register. Important: All GPIO pins are configured as GPIOs and tri-stated by default (GPIOAFSEL=0, GPIODEN=0, GPIOPDR=0, GPIOPUR=0, and GPIOPCTL=0, with the exception of the pins shown in the table below. A Power-On-Reset (POR) or asserting RST puts the pins back to their default state. Table 9-9. GPIO Pins With Non-Zero Reset Values Note: GPIO Pins Default State PA[1:0] UART0 GPIOAFSEL GPIODEN GPIOPDR GPIOPUR 0 0 0 GPIOPCTL 0 0x1 PA[5:2] SSI0 0 0 0 0 0x1 PB[3:2] I2C0 0 0 0 0 0x1 PC[3:0] JTAG/SWD 1 1 0 1 0x3 The GPIO commit control registers provide a layer of protection against accidental programming of critical hardware peripherals. Protection is provided for the NMI pin (PB7) and the four JTAG/SWD pins (PC[3:0]). Writes to protected bits of the GPIO Alternate Function Select (GPIOAFSEL) register (see page 450), GPIO Pull Up Select (GPIOPUR) register (see page 456), GPIO Pull-Down Select (GPIOPDR) register (see page 458), and GPIO Digital Enable (GPIODEN) register (see page 461) are not committed to storage unless the GPIO Lock (GPIOLOCK) register (see page 463) has been unlocked and the appropriate bits of the GPIO Commit (GPIOCR) register (see page 464) have been set. GPIO Pull-Up Select (GPIOPUR) GPIO Port A (APB) base: 0x4000.4000 GPIO Port A (AHB) base: 0x4005.8000 GPIO Port B (APB) base: 0x4000.5000 GPIO Port B (AHB) base: 0x4005.9000 GPIO Port C (APB) base: 0x4000.6000 GPIO Port C (AHB) base: 0x4005.A000 GPIO Port D (APB) base: 0x4000.7000 GPIO Port D (AHB) base: 0x4005.B000 GPIO Port E (APB) base: 0x4002.4000 GPIO Port E (AHB) base: 0x4005.C000 GPIO Port F (APB) base: 0x4002.5000 GPIO Port F (AHB) base: 0x4005.D000 GPIO Port G (APB) base: 0x4002.6000 GPIO Port G (AHB) base: 0x4005.E000 GPIO Port H (APB) base: 0x4002.7000 GPIO Port H (AHB) base: 0x4005.F000 GPIO Port J (APB) base: 0x4003.D000 GPIO Port J (AHB) base: 0x4006.0000 Offset 0x510 Type R/W, reset 31 30 29 28 27 26 25 24 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 8 7 6 5 4 3 2 1 0 RO 0 R/W - R/W - R/W - R/W - R/W - R/W - R/W - R/W - reserved Type Reset reserved Type Reset RO 0 PUE 456 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Bit/Field Name Type Reset 31:8 reserved RO 0x0000.00 7:0 PUE R/W - Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. Pad Weak Pull-Up Enable Value Description 0 The corresponding pin's weak pull-up resistor is disabled. 1 The corresponding pin's weak pull-up resistor is enabled. Setting a bit in the GPIOPDR register clears the corresponding bit in the GPIOPUR register. The change is effective on the second clock cycle after the write if accessing GPIO via the APB memory aperture. If using AHB access, the change is effective on the next clock cycle. The reset value for this register is 0x0000.0000 for GPIO ports that are not listed in Table 9-1 on page 428. July 03, 2014 457 Texas Instruments-Production Data General-Purpose Input/Outputs (GPIOs) Register 16: GPIO Pull-Down Select (GPIOPDR), offset 0x514 The GPIOPDR register is the pull-down control register. When a bit is set, a weak pull-down resistor on the corresponding GPIO signal is enabled. Setting a bit in GPIOPDR automatically clears the corresponding bit in the GPIO Pull-Up Select (GPIOPUR) register (see page 456). Important: All GPIO pins are configured as GPIOs and tri-stated by default (GPIOAFSEL=0, GPIODEN=0, GPIOPDR=0, GPIOPUR=0, and GPIOPCTL=0, with the exception of the pins shown in the table below. A Power-On-Reset (POR) or asserting RST puts the pins back to their default state. Table 9-10. GPIO Pins With Non-Zero Reset Values Note: GPIO Pins Default State PA[1:0] UART0 GPIOAFSEL GPIODEN GPIOPDR GPIOPUR 0 0 0 GPIOPCTL 0 0x1 PA[5:2] SSI0 0 0 0 0 0x1 PB[3:2] I2C0 0 0 0 0 0x1 PC[3:0] JTAG/SWD 1 1 0 1 0x3 The GPIO commit control registers provide a layer of protection against accidental programming of critical hardware peripherals. Protection is provided for the NMI pin (PB7) and the four JTAG/SWD pins (PC[3:0]). Writes to protected bits of the GPIO Alternate Function Select (GPIOAFSEL) register (see page 450), GPIO Pull Up Select (GPIOPUR) register (see page 456), GPIO Pull-Down Select (GPIOPDR) register (see page 458), and GPIO Digital Enable (GPIODEN) register (see page 461) are not committed to storage unless the GPIO Lock (GPIOLOCK) register (see page 463) has been unlocked and the appropriate bits of the GPIO Commit (GPIOCR) register (see page 464) have been set. GPIO Pull-Down Select (GPIOPDR) GPIO Port A (APB) base: 0x4000.4000 GPIO Port A (AHB) base: 0x4005.8000 GPIO Port B (APB) base: 0x4000.5000 GPIO Port B (AHB) base: 0x4005.9000 GPIO Port C (APB) base: 0x4000.6000 GPIO Port C (AHB) base: 0x4005.A000 GPIO Port D (APB) base: 0x4000.7000 GPIO Port D (AHB) base: 0x4005.B000 GPIO Port E (APB) base: 0x4002.4000 GPIO Port E (AHB) base: 0x4005.C000 GPIO Port F (APB) base: 0x4002.5000 GPIO Port F (AHB) base: 0x4005.D000 GPIO Port G (APB) base: 0x4002.6000 GPIO Port G (AHB) base: 0x4005.E000 GPIO Port H (APB) base: 0x4002.7000 GPIO Port H (AHB) base: 0x4005.F000 GPIO Port J (APB) base: 0x4003.D000 GPIO Port J (AHB) base: 0x4006.0000 Offset 0x514 Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 8 7 6 5 4 3 2 1 0 RO 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 reserved Type Reset reserved Type Reset RO 0 PDE 458 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Bit/Field Name Type Reset 31:8 reserved RO 0x0000.00 7:0 PDE R/W 0x00 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. Pad Weak Pull-Down Enable Value Description 0 The corresponding pin's weak pull-down resistor is disabled. 1 The corresponding pin's weak pull-down resistor is enabled. Setting a bit in the GPIOPUR register clears the corresponding bit in the GPIOPDR register. The change is effective on the second clock cycle after the write if accessing GPIO via the APB memory aperture. If using AHB access, the change is effective on the next clock cycle. July 03, 2014 459 Texas Instruments-Production Data General-Purpose Input/Outputs (GPIOs) Register 17: GPIO Slew Rate Control Select (GPIOSLR), offset 0x518 The GPIOSLR register is the slew rate control register. Slew rate control is only available when using the 8-mA drive strength option via the GPIO 8-mA Drive Select (GPIODR8R) register (see page 454). GPIO Slew Rate Control Select (GPIOSLR) GPIO Port A (APB) base: 0x4000.4000 GPIO Port A (AHB) base: 0x4005.8000 GPIO Port B (APB) base: 0x4000.5000 GPIO Port B (AHB) base: 0x4005.9000 GPIO Port C (APB) base: 0x4000.6000 GPIO Port C (AHB) base: 0x4005.A000 GPIO Port D (APB) base: 0x4000.7000 GPIO Port D (AHB) base: 0x4005.B000 GPIO Port E (APB) base: 0x4002.4000 GPIO Port E (AHB) base: 0x4005.C000 GPIO Port F (APB) base: 0x4002.5000 GPIO Port F (AHB) base: 0x4005.D000 GPIO Port G (APB) base: 0x4002.6000 GPIO Port G (AHB) base: 0x4005.E000 GPIO Port H (APB) base: 0x4002.7000 GPIO Port H (AHB) base: 0x4005.F000 GPIO Port J (APB) base: 0x4003.D000 GPIO Port J (AHB) base: 0x4006.0000 Offset 0x518 Type R/W, reset 0x0000.0000 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 3 2 1 0 R/W 0 R/W 0 R/W 0 R/W 0 reserved Type Reset RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14 13 12 11 10 9 8 7 6 5 4 reserved Type Reset RO 0 RO 0 RO 0 RO 0 SRL RO 0 RO 0 RO 0 Bit/Field Name Type Reset 31:8 reserved RO 0x0000.00 7:0 SRL R/W 0x00 RO 0 R/W 0 R/W 0 R/W 0 R/W 0 Description Software should not rely on the value of a reserved bit. To provide compatibility with future products, the value of a reserved bit should be preserved across a read-modify-write operation. Slew Rate Limit Enable (8-mA drive only) Value Description 1 Slew rate control is enabled for the corresponding pin. 0 Slew rate control is disabled for the corresponding pin. 460 July 03, 2014 Texas Instruments-Production Data ® Stellaris LM3S9U90 Microcontroller Register 18: GPIO Digital Enable (GPIODEN), offset 0x51C Note: Pins configured as digital inputs are Schmitt-triggered. The GPIODEN register is the digital enable register. By default, all GPIO signals except those listed below are configured out of reset to be undriven (tristate). Their digital function is disabled; they do not drive a logic value on the pin and they do not allow the pin voltage into the GPIO receiver. To use the pin as a digital input or output (either GPIO or alternate function), the corresponding GPIODEN bit must be set. Important: All GPIO pins are configured as GPIOs and tri-stated by default (GPIOAFSEL=0, GPIODEN=0, GPIOPDR=0, GPIOPUR=0, and GPIOPCTL=0, with the exception of the pins shown in the table below. A Power-On-Reset (POR) or asserting RST puts the pins back to their default state. Table 9-11. GPIO Pins With Non-Zero Reset Values Note: GPIO Pins Default State GPIOAFSEL GPIODEN GPIOPDR GPIOPUR GPIOPCTL PA[1:0] UART0 0 0 0 0 0x1 PA[5:2] SSI0 0 0 0 0 0x1 PB[3:2] I2C0 0 0 0 0 0x1 PC[3:0] JTAG/SWD 1 1 0 1 0x3 The GPIO commit control registers provide a layer of protection against accidental programming of critical hardware peripherals. Protection is provided for the NMI pin (PB7) and the four JTAG/SWD pins (PC[3:0]). Writes to protected bits of the GPIO Alternate Function Select (GPIOAFSEL) register (see page 450), GPIO Pull Up Select (GPIOPUR) register (see page 456), GPIO Pull-Down Select (GPIOPDR) register (see page 458), and GPIO Digital Enable (GPIODEN) register (see page 461) are not committed to storage unless the GPIO Lock (GPIOLOCK) register (see page 463) has been unlocked and the appropriate bits of the GPIO Commit (GPIOCR) register (see page 464) have been set. July 03, 2014 461 Texas Instruments-Production Data General-Purpose Input/Outputs (GPIOs) GPIO Digital Enable (GPIODEN) GPIO Port A (APB) base: 0x4000.4000 GPIO Port A (AHB) base: 0x4005.8000 GPIO Port B (APB) base: 0x4000.5000 GPIO Port B (AHB) base: 0x4005.9000 GPIO Port C (APB) base: 0x4000.6000 GPIO Port C (AHB) base: 0x4005.A000 GPIO Port D (APB) base: 0x4000.7000 GPIO Port D (AHB) base: 0x4005.B000 GPIO Port E (APB) base: 0x4002.4000 GPIO Port E (AHB) base: 0x4005.C000 GPIO Port F (APB) base: 0x4002.5000 GPIO Port F (AHB) base: 0x4005.D000 GPIO Port G (APB) base: 0x4002.6000 GPIO Port G (AHB) base: 0x4005.E000 GPIO Port H (APB) base: 0x4002.7000 GPIO Port H (AHB) base: 0x4005.F000 GPIO Port J (APB) base: 0x4003.D000 GPIO Port J (AHB) base: 0x4006.0000 Offset 0x51C Type R/W, reset 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 RO 0 RO 0 RO 0 RO 0 3 2 1 0 R/W - R/W - R/W - R/W - reserved Type Reset RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 RO 0 15 14