CP3BT10 Reprogrammable Connectivity Processor with Bluetooth® and USB Interfaces 1.0 General Description The CP3BT10 connectivity processor combines high performance with the massive integration needed for embedded Bluetooth applications. A powerful RISC core with on-chip SRAM and Flash memory provides high computing bandwidth, communications peripherals provide high I/O bandwidth, and an external bus provides system expandability. in the trade-off between battery size and operating time for handheld and portable applications. In addition to providing the features needed for the next generation of embedded Bluetooth products, the CP3BT10 is backed up by the software resources designers need for rapid time-to-market, including an operating system, BlueOn-chip communications peripherals include: Bluetooth tooth protocol stack implementation, reference designs, and Lower Link Controller, USB, ACCESS.bus, Microwire/SPI, an integrated development environment. Combined with UART, and Advanced Audio Interface (AAI). Additional on- National’s LMX5252 Bluetooth radio transceiver, the chip peripherals include DMA controller, CVSD/PCM con- CP3BT10 provides a complete Bluetooth system solution. version module, Timing and Watchdog Unit, Versatile Timer National Semiconductor offers a complete and industryUnit, Multi-Function Timer, and Multi-Input Wakeup. proven application development environment for CP3BT10 Bluetooth hand-held devices can be both smaller and lower applications, including the IAR Embedded Workbench, in cost for maximum consumer appeal. The low voltage and iSYSTEM winIDEA and iC3000 Active Emulator, Bluetooth advanced power-saving modes achieve new design points Development Board, Bluetooth Protocol Stack, and Application Software. Block Diagram Clock Generator 12 MHz and 32 kHz Oscillator PLL and Clock Generator Power-on-Reset Bluetooth Lower Link Controller CR16C CPU Core 256K Bytes Flash Program Memory 8K Bytes Flash Data 10K Bytes Static RAM RF Interface 1K Byte Sequencer RAM Protocol Core 4.5K Bytes Data RAM Serial Debug Interface CPU Core Bus Bus Interface Unit DMA Controller Peripheral Bus Controller Interrupt Control Unit Power Management CVSD/PCM Timing and Watchdog Unit Peripheral Bus USB GPIO Audio Interface Microwire/ SPI UART ACCESS .bus Versatile Timer Unit Muti-Function Timer Multi-Input Wake-Up DS144 Bluetooth is a registered trademark of Bluetooth SIG, Inc. and is used under license by National Semiconductor. TRI-STATE is a registered trademark of National Semiconductor Corporation. ©2005 National Semiconductor Corporation www.national.com CP3BT10 Reprogrammable Connectivity Processor with Bluetooth and USB Interfaces FINAL APRIL 2005 CP3BT10 Table of Contents 1.0 2.0 3.0 General Description . . . . . . . . . . . . . . . . . . . . . . . . . . 1 CPU Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Device Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 3.9 3.10 3.11 3.12 3.13 3.14 3.15 3.16 3.17 3.18 3.19 3.20 3.21 4.0 6.0 10.0 Operating Environment . . . . . . . . . . . . . . . . . . . . . . . . . Bus Interface Unit (BIU) . . . . . . . . . . . . . . . . . . . . . . . . Bus Cycles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . BIU Control Registers . . . . . . . . . . . . . . . . . . . . . . . . . . Wait and Hold States . . . . . . . . . . . . . . . . . . . . . . . . . . 20.0 Flash Memory Protection . . . . . . . . . . . . . . . . . . . . . . . Flash Memory Organization . . . . . . . . . . . . . . . . . . . . . Flash Memory Operations. . . . . . . . . . . . . . . . . . . . . . . Information Block Words. . . . . . . . . . . . . . . . . . . . . . . . Flash Memory Interface Registers . . . . . . . . . . . . . . . . 21.0 31 31 32 33 35 Non-Maskable Interrupts. . . . . . . . . . . . . . . . . . . . . . . . Maskable Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . Interrupt Controller Registers . . . . . . . . . . . . . . . . . . . . Maskable Interrupt Sources . . . . . . . . . . . . . . . . . . . . . Nested Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24.0 External Crystal Network . . . . . . . . . . . . . . . . . . . . . . . Main Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Slow Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . PLL Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . System Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Auxiliary Clocks. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Power-On Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . External Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Clock and Reset Registers . . . . . . . . . . . . . . . . . . . . . . 52 52 53 53 53 53 53 53 55 25.0 26.0 27.0 Active Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Power Save Mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . Idle Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Halt Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Hardware Clock Control . . . . . . . . . . . . . . . . . . . . . . . . Power Management Registers . . . . . . . . . . . . . . . . . . . Switching Between Power Modes. . . . . . . . . . . . . . . . . 57 57 57 57 57 58 59 Multi-Input Wake-Up . . . . . . . . . . . . . . . . . . . . . . . . . 61 Multi-Input Wake-Up Registers . . . . . . . . . . . . . . . . . . . 61 Programming Procedures . . . . . . . . . . . . . . . . . . . . . . . 63 28.0 29.0 30.0 Input/Output Ports. . . . . . . . . . . . . . . . . . . . . . . . . . . 64 14.1 14.2 Port Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64 Open-Drain Operation. . . . . . . . . . . . . . . . . . . . . . . . . . 67 www.national.com 2 Microwire Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . Master Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Slave Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Interrupt Generation. . . . . . . . . . . . . . . . . . . . . . . . . . . Microwire Interface Registers . . . . . . . . . . . . . . . . . . . 124 126 127 127 127 ACB Protocol Overview . . . . . . . . . . . . . . . . . . . . . . . . ACB Functional Description . . . . . . . . . . . . . . . . . . . . . ACCESS.bus Interface Registers . . . . . . . . . . . . . . . . Usage Hints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130 132 134 138 TWM Structure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Timer T0 Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . Watchdog Operation . . . . . . . . . . . . . . . . . . . . . . . . . . TWM Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Watchdog Programming Procedure. . . . . . . . . . . . . . . 139 139 140 140 142 Timer Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Timer Operating Modes . . . . . . . . . . . . . . . . . . . . . . . . Timer Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Timer I/O Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . Timer Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143 144 148 148 149 VTU Functional Description . . . . . . . . . . . . . . . . . . . . . 152 VTU Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156 Register Map. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 160 Register Bit Fields . . . . . . . . . . . . . . . . . . . . . . . . . . 171 Electrical Characteristics . . . . . . . . . . . . . . . . . . . . 182 27.1 27.2 27.3 27.4 27.5 27.6 27.7 27.8 27.9 27.10 27.11 27.12 27.13 27.14 Power Management . . . . . . . . . . . . . . . . . . . . . . . . . . 57 114 114 118 122 Versatile Timer Unit (VTU) . . . . . . . . . . . . . . . . . . . . 152 24.1 24.2 Triple Clock and Reset . . . . . . . . . . . . . . . . . . . . . . . 51 Functional Overview . . . . . . . . . . . . . . . . . . . . . . . . . . UART Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . UART Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Baud Rate Calculations . . . . . . . . . . . . . . . . . . . . . . . . Multi-Function Timer . . . . . . . . . . . . . . . . . . . . . . . . 143 23.1 23.2 23.3 23.4 23.5 47 47 47 49 50 109 109 110 110 110 110 110 111 111 Timing and Watchdog Module . . . . . . . . . . . . . . . . 139 22.1 22.2 22.3 22.4 22.5 41 41 42 43 43 43 Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . PCM Conversions . . . . . . . . . . . . . . . . . . . . . . . . . . . . CVSD Conversion . . . . . . . . . . . . . . . . . . . . . . . . . . . . PCM to CVSD Conversion. . . . . . . . . . . . . . . . . . . . . . CVSD to PCM Conversion. . . . . . . . . . . . . . . . . . . . . . Interrupt Generation. . . . . . . . . . . . . . . . . . . . . . . . . . . DMA Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Freeze . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . CVSD/PCM Converter Registers . . . . . . . . . . . . . . . . . ACCESS.bus Interface . . . . . . . . . . . . . . . . . . . . . . . 130 21.1 21.2 21.3 21.4 23.0 Channel Assignment. . . . . . . . . . . . . . . . . . . . . . . . . . . Transfer Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Operation Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Software DMA Request . . . . . . . . . . . . . . . . . . . . . . . . Debug Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . DMA Controller Register Set. . . . . . . . . . . . . . . . . . . . . Audio Interface Signals . . . . . . . . . . . . . . . . . . . . . . . . . 94 Audio Interface Modes . . . . . . . . . . . . . . . . . . . . . . . . . . 94 Bit Clock Generation . . . . . . . . . . . . . . . . . . . . . . . . . . . 97 Frame Clock Generation . . . . . . . . . . . . . . . . . . . . . . . . 97 Audio Interface Operation . . . . . . . . . . . . . . . . . . . . . . . 97 Communication Options. . . . . . . . . . . . . . . . . . . . . . . . . 99 Audio Interface Registers. . . . . . . . . . . . . . . . . . . . . . . 102 Usage Hints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108 Microwire/SPI Interface . . . . . . . . . . . . . . . . . . . . . . 124 20.1 20.2 20.3 20.4 20.5 Module Configuration Register (MCFG) . . . . . . . . . . . . 30 Module Status Register (MSTAT) . . . . . . . . . . . . . . . . . 30 75 75 78 93 UART Module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114 19.1 19.2 19.3 19.4 25 26 26 26 29 Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47 13.1 13.2 14.0 19.0 22.0 12.1 12.2 12.3 12.4 12.5 12.6 12.7 13.0 16 16 17 18 19 20 20 9.1 9.2 9.3 9.4 9.5 9.6 11.1 11.2 11.3 11.4 11.5 11.6 11.7 11.8 11.9 12.0 General-Purpose Registers . . . . . . . . . . . . . . . . . . . . . Dedicated Address Registers . . . . . . . . . . . . . . . . . . . . Processor Status Register (PSR) . . . . . . . . . . . . . . . . . Configuration Register (CFG) . . . . . . . . . . . . . . . . . . . . Addressing Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . Stacks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Instruction Set . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Functional States . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Endpoint Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . USB Controller Registers. . . . . . . . . . . . . . . . . . . . . . . . Transceiver Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . CVSD/PCM Conversion Module . . . . . . . . . . . . . . . 109 18.1 18.2 18.3 18.4 18.5 18.6 18.7 18.8 18.9 Pin Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 DMA Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 10.1 10.2 10.3 10.4 10.5 11.0 18.0 68 69 72 72 73 73 73 74 Advanced Audio Interface . . . . . . . . . . . . . . . . . . . . . 94 17.1 17.2 17.3 17.4 17.5 17.6 17.7 17.8 Flash Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 8.1 8.2 8.3 8.4 8.5 9.0 17.0 RF Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Serial Interface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . LMX5251 Power-Up Sequence . . . . . . . . . . . . . . . . . . . LMX5252 Power-Up Sequence . . . . . . . . . . . . . . . . . . . Bluetooth Sleep Mode . . . . . . . . . . . . . . . . . . . . . . . . . . Bluetooth Global Registers . . . . . . . . . . . . . . . . . . . . . . Bluetooth Sequencer RAM . . . . . . . . . . . . . . . . . . . . . . Bluetooth Shared Data RAM . . . . . . . . . . . . . . . . . . . . . USB Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75 16.1 16.2 16.3 16.4 System Configuration Registers . . . . . . . . . . . . . . . 30 7.1 7.2 8.0 16.0 Memory. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 6.1 6.2 6.3 6.4 6.5 7.0 4 4 4 4 4 4 4 5 5 5 5 5 5 5 5 6 6 6 6 6 6 CPU Architecture. . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 5.1 5.2 5.3 5.4 5.5 5.6 5.7 Bluetooth Controller . . . . . . . . . . . . . . . . . . . . . . . . . 68 15.1 15.2 15.3 15.4 15.5 15.6 15.7 15.8 Device Pinouts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 4.1 5.0 CR16C CPU Core. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Input/Output Ports. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Bus Interface Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Interrupt Control Unit (ICU) . . . . . . . . . . . . . . . . . . . . . . . Bluetooth LLC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . USB. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Multi-Input Wake-up . . . . . . . . . . . . . . . . . . . . . . . . . . . . Triple Clock and Reset . . . . . . . . . . . . . . . . . . . . . . . . . . Power Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . Multi-Function Timer . . . . . . . . . . . . . . . . . . . . . . . . . . . . Versatile Timer Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . Timing and Watchdog Module . . . . . . . . . . . . . . . . . . . . UART . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Microwire/SPI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ACCESS.bus Interface . . . . . . . . . . . . . . . . . . . . . . . . . . DMA Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Advanced Audio interface . . . . . . . . . . . . . . . . . . . . . . . . CVSD/PCM Conversion Module . . . . . . . . . . . . . . . . . . . Serial Debug Interface . . . . . . . . . . . . . . . . . . . . . . . . . . Development Support . . . . . . . . . . . . . . . . . . . . . . . . . . . 15.0 Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . DC Electrical Characteristics . . . . . . . . . . . . . . . . . . . USB Transceiver Electrical Characteristics . . . . . . . . Flash Memory On-Chip Programming . . . . . . . . . . . . . Output Signal Levels . . . . . . . . . . . . . . . . . . . . . . . . . . Clock and Reset Timing. . . . . . . . . . . . . . . . . . . . . . . . I/O Port Timing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Advanced Audio Interface (AAI) Timing. . . . . . . . . . . . Microwire/SPI Timing . . . . . . . . . . . . . . . . . . . . . . . . . . ACCESS.bus Timing . . . . . . . . . . . . . . . . . . . . . . . . . . USB Port AC Characteristics . . . . . . . . . . . . . . . . . . . . Multi-Function Timer (MFT) Timing . . . . . . . . . . . . . . . Versatile Timing Unit (VTU) Timing . . . . . . . . . . . . . . . External Bus Timing. . . . . . . . . . . . . . . . . . . . . . . . . . . 182 182 183 184 185 185 187 188 190 195 198 198 199 200 Pin Assignments . . . . . . . . . . . . . . . . . . . . . . . . . . . 206 Revision History . . . . . . . . . . . . . . . . . . . . . . . . . . . . 208 Physical Dimensions . . . . . . . . . . . . . . . . . . . . . . . . 209 CPU Features CPU Features Extensive Power and Clock Management Support Fully static RISC processor core, capable of operating from 0 to 24 MHz with zero wait/hold states Minimum 41.7 ns instruction cycle time with a 24-MHz internal clock frequency, based on a 12-MHz external input 30 independently vectored peripheral interrupts On-Chip Memory I/O port operation at 2.5V to 3.3V Core logic operation at 2.5V On-chip power-on reset On-chip Phase Locked Loop Support for multiple clock options Dual clock and reset Power-down modes Power Supply 256K bytes reprogrammable Flash program memory 8K bytes Flash data memory 10K bytes of static RAM data memory Addresses up to 8 Mbytes of external memory Temperature Range -40°C to +85°C (Industrial) Broad Range of Hardware Communications Peripherals Packages Bluetooth Lower Link Controller (LLC) including a shared 4.5K byte Bluetooth RAM and 1K byte Bluetooth Sequencer RAM Full-speed USB node including seven Endpoint-FIFOs conforming to USB 1.1 specification ACCESS.bus serial bus (compatible with Philips I2C bus) 8/16-bit SPI, Microwire/Plus serial interface Universal Asynchronous Receiver/Transmitter (UART) Advanced Audio Interface (AAI) to connect to external 8/ 13-bit PCM Codecs as well as to ISDN-Controllers through the IOM-2 interface (slave only) CVSD/PCM converter supporting one bidirectional audio connection CSP-48, LQFP-100 Complete Development Environment Pre-integrated hardware and software support for rapid prototyping and production Integrated environment Project manager Multi-file C source editor High-level C source debugger Comprehensive, integrated, one-stop technical support Bluetooth Protocol Stack Applications can interface to the high-level protocols or directly to the low-level Host Controller Interface (HCI) General-Purpose Hardware Peripherals Transport layer support allows HCI command-based in Dual 16-bit Multi-Function Timer terface over UART or USB port Versatile Timer Unit with four subsystems (VTU) Baseband (Link Controller) minimizes the performance Four channel DMA controller demand on the CPU Timing and Watchdog Unit Link Manager (LM) Flexible I/O Logical Link Control and Adaptation Protocol (L2CAP) Up to 37 general-purpose I/O pins (shared with on-chip Service Discovery Protocol (SDP) RFCOMM Serial Port Emulation Protocol peripheral I/O pins) Programmable I/O pin characteristics: TRI-STATE out- All packet types, piconet, and scatternet functionality supported put, push-pull output, weak pull-up input, high-impedance input Schmitt triggers on general purpose inputs Multi-Input Wakeup CP3BT10 Connectivity Processor Selection Guide NSID Speed Temp. Range (MHz) Program Flash (kBytes) Data External SRAM Flash Address (kBytes) (kBytes) Lines I/Os Package Type Pack Method Tray CP3BT10G38 24 -40° to +85°C 256 8 10 22 37 LQFP-100 CP3BT10G38X 24 -40° to +85°C 256 8 10 22 37 LQFP-100 1000-T&R CP3BT10K38X 24 -40° to +85°C 256 8 10 0 21 CSP-48 2500-T&R CP3BT10K38Y 24 -40° to +85°C 256 8 10 0 21 CSP-48 250-T&R T&R = Tape and Reel 3 www.national.com CP3BT10 2.0 CP3BT10 3.0 Device Overview The CP3BT10 connectivity processor is complete microcomputer with all system timing, interrupt logic, program memory, data memory, I/O ports included on-chip, making them well-suited to a wide range of embedded applications. The block diagram on page 1 shows the major on-chip components of the CP3BT10. The I/O pin characteristics are fully programmable. Each pin can be configured to operate as a TRI-STATE output, pushpull output, weak pull-up input, or high-impedance input. For more information, please refer to the CR16C Programmer’s Reference Manual (document number 424521772101, which may be downloaded from National’s web site at http://www.national.com). possible memory access. To achieve fastest possible program execution, appropriate values must be programmed. These settings vary with the clock frequency and the type of off-chip device being accessed. 3.2 3.5 3.4 BUS INTERFACE UNIT The Bus Interface Unit (BIU) controls access to internal/external memory and I/O. It determines the configured param3.1 CR16C CPU CORE eters for bus access (such as the number of wait states for The CP3BT10 implements the CR16C CPU core module. memory access) and issues the appropriate bus signals for The high performance of the CPU core results from the im- each requested access. plementation of a pipelined architecture with a two-bytes- The BIU uses a set of control registers to determine how per-cycle pipelined system bus. As a result, the CPU can many wait states and hold states are used when accessing support a peak execution rate of one instruction per clock Flash program memory, and the I/O area (Port B and Port cycle. C). At start-up, the configuration registers are set for slowest MEMORY The CP3BT10 supports a uniform linear address space of up to 16 megabytes. Three types of on-chip memory occupy specific regions within this address space: INTERRUPT CONTROL UNIT (ICU) The ICU receives interrupt requests from internal and external sources and generates interrupts to the CPU. An interrupt is an event that temporarily stops the normal flow of program execution and causes a separate interrupt handler to be executed. After the interrupt is serviced, CPU execution continues with the next instruction in the program following the point of interruption. 256K bytes of Flash program memory 8K bytes of Flash data memory 10K bytes of static RAM Up to 8M bytes of external memory (100-pin devices) Interrupts from the timers, UART, Microwire/SPI interface, and Multi-Input Wake-Up, are all maskable interrupts; they can be enabled or disabled by software. There are 32 maskable interrupts, assigned to 32 linear priority levels. The 256K bytes of Flash program memory are used to store the application program, Bluetooth protocol stack, and realtime operating system. The Flash memory has security features to prevent unintentional programming and to prevent unauthorized access to the program code. This memory can be programmed with an external programming unit or with the device installed in the application system (in-system programming). The highest-priority interrupt is the Non-Maskable Interrupt (NMI), which is generated by a signal received on the NMI input pin. 3.6 BLUETOOTH LLC The 8K bytes of Flash data memory are used for non-volatile storage of data entered by the end-user, such as config- The integrated hardware Bluetooth Lower Link Controller (LLC) complies to the Bluetooth Specification Version 1.1 uration settings. and integrates the following functions: The 10K bytes of static RAM are used for temporary storage of data and for the program stack and interrupt stack. Read 4.5K-byte dedicated Bluetooth data RAM and write operations can be byte-wide or word-wide, de- 1K-byte dedicated Bluetooth Sequencer RAM Support of all Bluetooth 1.1 packet types pending on the instruction executed by the CPU. Support for fast frequency hopping of 1600 hops/s Up to 8M bytes of external memory can be added on an ex- Access code correlation and slot timing recovery circuit ternal bus. The external bus is only available on devices in Power Management Control Logic 100-pin packages. BlueRF-compatible interface to connect with National’s LMX5252 and other RF transceiver chips For Flash program and data memory, the device internally generates the necessary voltages for programming. No ad3.7 USB ditional power supply is required. The USB node is a Universal Serial Bus (USB) Node con3.3 INPUT/OUTPUT PORTS troller compatible with USB Specification, 1.0 and 1.1. It inThe device has up to 37 software-configurable I/O pins, or- tegrates the required USB transceiver, the Serial Interface ganized into five ports called Port B, Port C, Port G, Port H, Engine (SIE), and USB endpoint FIFOs. A total of seven and Port I. Each pin can be configured to operate as a gen- endpoint pipes are supported: one bidirectional pipe for the eral-purpose input or general-purpose output. In addition, mandatory control EP0 and an additional six pipes for unidimany I/O pins can be configured to operate as inputs or out- rectional endpoints to support USB interrupt, bulk, and isoputs for on-chip peripheral modules such as the UART, tim- chronous data transfers. ers, or Microwire/SPI interface. www.national.com 4 MULTI-INPUT WAKE-UP 3.11 MULTI-FUNCTION TIMER The Multi-Input Wake-Up (MIWU) module can be used for either of two purposes: to provide inputs for waking up (exiting) from the Halt, Idle, or Power Save mode; or to provide general-purpose edge-triggered maskable interrupts from external sources. This 16-channel module generates four programmable interrupts to the CPU based on the signals received on its 16 input channels. Channels can be individually enabled or disabled, and programmed to respond to positive or negative edges. The Multi-Function Timer (MFT) module contains a pair of 16-bit timer/counter registers. Each timer/counter unit can be configured to operate in any of the following modes: This module generates a slow System Clock (32.768 kHz) from an optional external crystal network. The Slow Clock is used for operating the device in power-save mode. The 32.768 kHz external crystal network is optional, because the low speed System Clock can be derived from the highspeed clock by a prescaler. Also, two independent clocks divided down from the high speed clock are available on output pins. The Versatile Timer Unit (VTU) module contains four independent timer subsystems, each operating in either dual 8bit PWM configuration, as a single 16-bit PWM timer, or a 16-bit counter with two input capture channels. Each of the four timer subsystems offer an 8-bit clock prescaler to accommodate a wide range of frequencies. The Triple Clock and Reset module provides the clock signals required for the operation of the various CP3BT10 onchip modules. From external crystal networks, it generates the Main Clock, which can be scaled up to 24 MHz from an external 12 MHz input clock, and a 32.768 kHz secondary System Clock. The 12 MHz external clock is primarily used as the reference frequency for the on-chip PLL. Also the clock for modules which require a fixed clock rate (e.g. the Bluetooth LLC and the CVSD/PCM transcoder) is generated through prescalers from the 12 MHz clock. The PLL generates the input clock for the USB node and may be used to drive the high-speed System Clock through a prescaler. Alternatively, the high speed System Clock can be derived directly from the 12 MHz Main Clock. The Timing and Watchdog Module (TWM) contains a RealTime timer and a Watchdog unit. The Real-Time Clock Timing function can be used to generate periodic real-time based system interrupts. The timer output is one of 16 inputs to the Multi-Input-Wake-Up module which can be used to exit from a power-saving mode. The Watchdog unit is designed to detect the application program getting stuck in an infinite loop resulting in loss of program control or “runaway” programs. When the watchdog triggers, it resets the device. The TWM is clocked by the low-speed System Clock. Processor-Independent Pulse Width Modulation (PWM) mode—Generates pulses of a specified width and duty cycle and provides a general-purpose timer/counter. Dual Input Capture mode—Measures the elapsed time between occurrences of external event and provides a general-purpose timer/counter. Dual Independent Timer mode—Generates system tim3.9 TRIPLE CLOCK AND RESET ing signals or counts occurrences of external events. The Triple Clock and Reset module generates a high-speed Single Input Capture and Single Timer mode—Provides main System Clock from an external crystal network. It also one external event counter and one system timer. provides the main system reset signal and a power-on reset 3.12 VERSATILE TIMER UNIT function. 3.13 3.14 UART The UART supports a wide range of programmable baud rates and data formats, parity generation, and several error detection schemes. The baud rate is generated on-chip, under software control. In addition, this module generates the device reset by using reset input signals coming from an external reset and various on-chip modules. 3.10 TIMING AND WATCHDOG MODULE The UART offers a wake-up condition from the power-save mode using the Multi-Input Wake-Up module. POWER MANAGEMENT 3.15 The Power Management Module (PMM) improves the efficiency of the device by changing the operating mode and power consumption to match the required level of activity. MICROWIRE/SPI The Microwire/SPI (MWSPI) interface module supports synchronous serial communications with other devices that conform to Microwire or Serial Peripheral Interface (SPI) specifications. It supports 8-bit and 16-bit data transfers. The device can operate in any of four power modes: Active—The device operates at full speed using the highfrequency clock. All device functions are fully operational. Power Save—The device operates at reduced speed using the Slow Clock. The CPU and some modules can continue to operate at this low speed. Idle—The device is inactive except for the Power Management Module and Timing and Watchdog Module, which continue to operate using the Slow Clock. Halt—The device is inactive but still retains its internal state (RAM and register contents). The Microwire interface allows several devices to communicate over a single system consisting of four wires: serial in, serial out, shift clock, and slave enable. At any given time, the Microwire interface operates as the master or a slave. The Microwire interface supports the full set of slave select for multi-slave implementation. In master mode, the shift clock is generated on chip under software control. In slave mode, a wake-up out of powersave mode is triggered using the Multi-Input Wake-Up module. 5 www.national.com CP3BT10 3.8 CP3BT10 3.16 ACCESS.BUS INTERFACE 3.18 The ACCESS.bus interface module (ACB) is a two-wire serial interface with the ACCESS.bus physical layer. It is also compatible with Intel’s System Management Bus (SMBus) and Philips’ I2C bus. The ACB module can be configured as a bus master or slave, and can maintain bidirectional communications with both multiple master and slave devices. ADVANCED AUDIO INTERFACE The audio interface provides a serial synchronous, full-duplex interface to codecs and similar serial devices. Transmit and receive paths operate asynchronously with respect to each other. Each path uses three signals for communication: shift clock, frame synchronization, and data. In case receive and transmit use separate shift clocks and The ACCESS.bus receiver can trigger a wake-up condition frame sync signals, the interface operates in its asynchroout of the low-power modes using the Multi-Input Wake-Up nous mode. Alternatively, the transmit and receive path can module. share the same shift clock and frame sync signals for synchronous mode operation. 3.17 DMA CONTROLLER The interface can handle data words of either 8- or 16-bit length and data frames can consist of up to four slots. The Direct Memory Access Controller (DMAC) can speed up data transfer between memory and I/O devices or between two memories, relative to data transfers performed directly by the CPU. A method called cycle-stealing allows the CPU and the DMAC to use the core bus in parallel. The DMAC implements four independent DMA channels. DMA requests from a primary and a secondary source are recognized for each DMA channel, as well as a software DMA request issued directly by the CPU. Table 1 shows the DMA channel assignment on the CP3BT10 architecture. The following on-chip modules can assert a DMA request to the DMAC: In the normal mode of operation, the interface only transfers one word at a periodic rate. In the network mode, the interface transfers multiple words at a periodic rate. The periodic rate is also called a data frame and each word within one frame is called a slot. The beginning of each new data frame is marked by the frame sync signal. 3.19 CVSD/PCM CONVERSION MODULE The CVSD/PCM module performs conversion between CVSD and PCM data, in which the CVSD encoding is as defined in the Bluetooth specification 1.0 and the PCM data can be 8-bit µ-Law, 8-bit A-Law, or 13-bit to 16-bit Linear. CR16C (Software DMA request) USB UART Advanced Audio Interface CVSD/PCM Converter 3.20 SERIAL DEBUG INTERFACE The Serial Debug Interface module (SDI module) provides a JTAG-based serial link to an external debugger, for example running on a PC. In addition, the SDI module integrates Table 1 shows how the four DMA channels are assigned an on-chip debug module, which allows the user to set up to to the modules listed above. four hardware breakpoints on instruction execution and data transfer. The SDI module can act as a CPU bus master to Table 1 DMA Channel Assignment access all memory mapped resources, such as RAM and peripherals. It also provides fast program download into the Primary/ Channel Peripheral Transaction on-chip Flash program memory using the JTAG interface. Secondary Primary USB Read/Write Secondary UART Read Primary UART Write Secondary Unused N/A Primary AAI Read Secondary CVSD/PCM Read Primary AAI Write Secondary CVSD/PCM Write Note: The SDI module may assert Freeze mode to gather information, which may cause periodic fluctuations in response (bus availability, interrupt latency, etc.). Anomalous behavior often may be traced to SDI activity. 0 3.21 1 DEVELOPMENT SUPPORT In addition to providing the features needed for the next generation of embedded Bluetooth products, the CP3BT10 is backed up by the software resources designers need for rapid time-to-market, including an operating system, Bluetooth protocol stack implementation, peripheral drivers, reference designs, and an integrated development environment. Combined with National’s LMX5252 Bluetooth radio transceiver, the CP3BT10 provides a total Bluetooth system solution. 2 3 National Semiconductor offers a complete and industryproven application development environment for CP3BT10 applications, including the IAR Embedded Workbench, iSYSTEM winIDEA and iC3000 Active Emulator, Bluetooth Development Board, Bluetooth Protocol Stack, and Application Software. See your National Semiconductor sales representative for current information on availability and features of emulation equipment and evaluation boards. www.national.com 6 CP3BT10 4.0 Device Pinouts X1CKI/BBCLK X1CKO 12 MHz Crystal or Ext. Clock X2CKI X2CKO 32.768 kHz Crystal Power Supply 2 4 6 Chip Reset AVCC AGND VCC IOVCC GND RESET CP3BT10 (LQFP-100) PB[7:0] PC[7:0] A[21:0] SEL0 SEL1 SEL2 SELIO WR0 WR1 RD JTAG I/F to Debugger/ Programmer TCK RDY SDA SCL ACCESS.bus UVCC 22 External Bus Interface 32.768 kHz Crystal/ RFDATA X2CKI PIO/RFSYNC X2CKO PI1/RFCE Power Supply 2 AVCC PI3/SCLK AGND CP3BT10 PI4/SDAT PI5/SLE (CSP-48) VCC IOVCC PI6/BTSEQ2/WUI9 GND PI7/BTSEQ3/TA Chip Reset PI7/BTSEQ3/TA PG0/RXD/WUI10 PG1/TXD/WUI11 PG2/RTS/WUI12 PG3/CTS/WUI13 PG1/TXD/WUI11 RF Interface PG2/RTS/WUI12 USB ENV0 ENV1 ENV2 Mode Selection PH0/MSK/TIO1 PH1/MDIDO/TIO2 PH2/MDODI/TIO3 PH3/MWCS/TIO4 RF/MFT UART/ MIWU PH0/MSK/TIO1 RF/MIWU PH2/MDODI/TIO3 TMS JTAG I/F to Debugger/ Programmer RF/MFT UART/ MIWU Microwire/ SPI/ VTU PH3/MWCS/TIO4 TDI TDO PH4/SCK/TIO5 TCK PH5/SFS/TIO6 RDY PH6/STD/TIO7 AAI/ VTU PH7/SRD/TIO8 Mode Selection PG5/SRFS/NMI ENV0 AAI/NMI ENV1 RF/AAI Microwire/ SPI/ VTU PH4/SCK/TIO5 PH5/SFS/TIO6 PH6/STD/TIO7 PH7/SRD/TIO8 AAI/ VTU PG5/SRFS/NMI AAI/NMI PI2/BTSEQ3/SRCLK RF/MIWU PG3/CTS/WUI13 PI2/BTSEQ1/SRCLK D+ DUVCC UGND RF Interface PG0/RXD/WUI10 RESET PH1/MDIDO/TIO2 PI6/BTSEQ2/WUI9 USB UGND 4 RFDATA PIO/RFSYNC PI1/RFCE D- X1CKO 2 PI3/SCLK PI4/SDAT PI5/SLE TMS TDI TDO 8 D+ X1CKI/BBCLK 12 MHz Crystal or Ext. Clock 8 RF/AAI DS148 Table 2 Pin Assignments for 100-Pin Package Pin Name Alternate Function(s) Pin Numbers Type A14 1 O A13 2 O A12 3 O A11 4 O A10 5 O PH6 STD/TIO7 6 GPIO PH7 SRD/TIO8 7 GPIO ENV1 8 I/O A9 9 O A8 10 O A7 11 O A6 12 O A5 13 O 7 www.national.com CP3BT10 Table 2 Pin Assignments for 100-Pin Package Pin Name Alternate Function(s) Pin Numbers Type A4 14 O VCC 15 PWR X2CKI 16 I X2CKO 17 O GND 18 PWR AVCC 19 PWR AGND 20 PWR IOVCC 21 PWR X1CKO 22 O 23 I GND 24 PWR RFDATA 25 I/O A3 26 O A2 27 O A1 28 O A0 29 O X1CKI BBCLK PI0 RFSYNC 30 GPIO PI1 RFCE 31 GPIO PI2 BTSEQ1/SRCLK 32 GPIO PB0 D0 33 GPIO PB1 D1 34 GPIO PB2 D2 35 GPIO PB3 D3 36 GPIO PB4 D4 37 GPIO PB5 D5 38 GPIO PB6 D6 39 GPIO PB7 D7 40 GPIO 41 PWR GND IOVCC 42 PWR PI3 SCLK 43 GPIO PI4 SDAT 44 GPIO PI5 SLE 45 GPIO PI6 BTSEQ2/WUI9 46 GPIO PI7 BTSEQ3/TA 47 GPIO PG0 RXD/WUI10 48 GPIO PG1 TXD/WUI11 49 GPIO PC0 D8 50 GPIO PG2 RTS/WUI12 51 GPIO PG3 CTS/WUI13 52 GPIO PC1 D9 53 GPIO PC2 D10 54 GPIO PC3 D11 55 GPIO PC4 D12 56 GPIO www.national.com 8 Pin Name Alternate Function(s) Pin Numbers Type PC5 D13 57 GPIO PC6 D14 58 GPIO PC7 D15 59 GPIO PG5 SRFS/NMI 60 GPIO TMS 61 I TCK 62 I TDI 63 I GND 64 PWR IOVCC 65 PWR ENV2 66 I/O SEL0 67 O SCL 68 I/O SDA 69 I/O TDO 70 O D- 71 I/O D+ 72 I/O UVCC 73 PWR UGND 74 PWR RDY 75 O SEL1 76 O SEL2 77 O SELIO 78 O A21 79 O A20 80 O PH0 MSK/TIO1 81 GPIO PH1 MDIDO/TIO2 82 GPIO PH2 MDODI/TIO3 83 GPIO PH3 MWCS/TIO4 84 GPIO ENV0 85 I/O IOVCC 86 PWR GND 87 PWR VCC 88 PWR GND 89 PWR RESET 90 I RD 91 O WR0 92 O WR1 93 O A19 94 O A18 95 O A17 96 O A16 97 O A15 98 O 9 www.national.com CP3BT10 Table 2 Pin Assignments for 100-Pin Package CP3BT10 Table 2 Pin Assignments for 100-Pin Package Pin Name Alternate Function(s) Pin Numbers Type PH4 SCK/TIO5 99 GPIO PH5 SFS/TIO6 100 GPIO Note 1: The ENV0, ENV1, ENV2, TCK, TDI, and TMS pins each have a weak pull-up to keep the input from floating. Note 2: The RESET input has a weak pulldown. Note 3: These functions are always enabled, due to the direct low-impedance path to these pins. Table 3 Pin Assignments for 48-Pin Package Pin Name Alternate Function(s) Pin Number Type PH6 STD/TIO7 1 GPIO PH7 SRD/TIO8 2 GPIO ENV1 3 I/O VCC 4 PWR X2CKI 5 I X2CKO 6 O GND 7 PWR AVCC 8 PWR AGND 9 PWR IOVCC 10 PWR X1CKO 11 O 12 I 13 PWR X1CKI BBCLK GND RFDATA 14 I/O PI0 RFSYNC 15 GPIO PI1 RFCE 16 GPIO PI2 BTSEQ1/SRCLK 17 GPIO PI3 SCLK 18 GPIO PI4 SDAT 19 GPIO PI5 SLE 20 GPIO PI6 BTSEQ2/WUI9 21 GPIO PI7 BTSEQ3/TA 22 GPIO PG0 RXD/WUI10 23 GPIO PG1 TXD/WUI11 24 GPIO PG2 RTS/WUI12 25 GPIO PG3 CTS/WUI13 26 GPIO PG5 SRFS/NMI 27 GPIO TMS 28 I TCK 29 I TDI 30 I GND 31 PWR IOVCC 32 PWR TDO 33 O, GPIO www.national.com D- 34 O, GPIO D+ 35 I/O UVCC 36 PWR, I/O 10 Alternate Function(s) UGND RDY Pin Number Type 37 PWR, O 38 O PH0 MSK/TIO1 39 GPIO PH1 MDIDO/TIO2 40 GPIO PH2 MDODI/TIO3 41 GPIO PH3 MWCS/TIO4 42 GPIO ENV0 43 I/O VCC 44 PWR GND 45 PWR 46 I PH4 SCK/TIO5 47 GPIO PH5 SFS/TIO6 48 GPIO RESET Note 1: The ENV0, ENV1 and ENV2, TCK, TDI and TMS pins each have a weak pull-up to keep the input from floating. Note 2: The RESET input has a weak pulldown. Note 3: These functions are always enabled, due to the direct low-impedance path to these pins. 11 www.national.com CP3BT10 Pin Name CP3BT10 4.1 PIN DESCRIPTIONS Some pins may be enabled as general-purpose I/O-port pins or as alternate functions associated with specific peripherals or interfaces. These pins may be individually con- figured as port pins, even when the associated peripheral or interface is enabled. Table 4 lists the device pins. Table 4 CP3BT10 Pin Descriptions for the 100-Pin LQFP Package Name Pins I/O Alternate Name Primary Function Alternate Function X1CKI 1 Input 12 MHz Oscillator Input BBCLK BB reference clock for the RF Interface X1CKO 1 Output 12 MHz Oscillator Output None None X2CKI 1 Input 32 kHz Oscillator Input None None X2CKO 1 Output 32 kHz Oscillator Output None None AVCC 1 Input PLL Analog Power Supply None None IOVCC 4 Input 2.5V - 3.3V I/O Power Supply None None VCC 2 Input 2.5V Core Logic Power Supply None None GND 6 Input Reference Ground None None AGND 1 Input PLL Analog Ground None None RESET 1 Input Chip general reset None None TMS 1 Input JTAG Test Mode Select (with internal weak pull-up) None None TDI 1 Input JTAG Test Data Input (with internal weak pull-up) None None TDO 1 Output JTAG Test Data Output None None TCK 1 Input JTAG Test Clock Input (with internal weak pull-up) None None RDY 1 Output NEXUS Ready Output None None RXD UART Receive Data Input PG0 1 I/O Generic I/O WUI10 Multi-Input Wake-Up Channel 10 TXD UART Transmit Data Output WUI11 Multi-Input Wake-Up Channel 11 RTS UART Ready-To-Send Output WUI12 Multi-Input Wake-Up Channel 12 CTS UART Clear-To-Send Input WUI13 Multi-Input Wake-Up Channel 13 SRFS AAI Receive Frame Sync NMI Non-Maskable Interrupt Input MSK SPI Shift Clock TIO1 Versatile Timer Channel 1 MDIDO SPI Master In Slave Out TIO2 Versatile Timer Channel 2 MDODI SPI Master Out Slave In TIO3 Versatile Timer Channel 3 PG1 PG2 PG3 PG5 PH0 PH1 PH2 1 1 1 1 1 1 1 www.national.com I/O I/O I/O I/O I/O I/O I/O Generic I/O Generic I/O Generic I/O Generic I/O Generic I/O Generic I/O Generic I/O 12 PH3 PH4 PH5 PH6 PH7 Pins 1 1 1 1 1 I/O I/O I/O I/O I/O I/O Alternate Name Primary Function Alternate Function MWCS SPI Slave Select Input TIO4 Versatile Timer Channel 4 SCK AAI Clock TIO5 Versatile Timer Channel 5 SFS AAI Frame Synchronization TIO6 Versatile Timer Channel 6 STD AAI Transmit Data Output TIO7 Versatile Timer Channel 7 SRD AAI Receive Data Input TIO8 Versatile Timer Channel 8 Generic I/O Generic I/O Generic I/O Generic I/O Generic I/O RFDATA 1 I/O Bluetooth RX/TX Data Pin None None PI0 1 I/O Generic I/O RFSYNC BT AC Correlation/TX Enable Output PI1 1 I/O Generic I/O RFCE BT RF Chip Enable Output BTSEQ1 Bluetooth Sequencer Status PI2 1 I/O Generic I/O SRCLK AAI Receive Clock PI3 1 I/O Generic I/O SCLK BT Serial I/F Shift Clock Output PI4 1 I/O Generic I/O SDAT BT Serial I/F Data PI5 1 I/O Generic I/O SLE BT Serial I/F Load Enable Output WUI9 Multi-Input Wake-Up Channel 9 PI6 1 I/O Generic I/O BTSEQ2 Bluetooth Sequencer Status TA Multi Function Timer Port A BTSEQ3 Bluetooth Sequencer Status PI7 1 I/O Generic I/O SDA 1 I/O ACCESS.bus Serial Data None None SCL 1 I/O ACCESS.bus Clock None None D+ 1 I/O USB D+ Upstream Port None None D- 1 I/O USB D- Upstream Port None None UVCC 1 Input 3.3V USB Transceiver Supply None None UGND 1 Input USB Transceiver Ground None None PB[7:0] 8 I/O Generic I/O D[7:0] External Data Bus Bit 0 to 7 PC[7:0] 8 I/O Generic I/O D[15:8] External Data Bus Bit 8 to 15 A[21:0] 22 Output External Address Bus Bit 0 to 21 None None SEL0 1 Output Chip Select for Zone 0 None None SEL1 1 Output Chip Select for Zone 1 None None SEL2 1 Output Chip Select for Zone 2 None None SELIO 1 Output Chip Select for Zone I/O Zone None None WR0 1 Output External Memory Write Low Byte None None WR1 1 Output External Memory Write High Byte None None 13 www.national.com CP3BT10 Name CP3BT10 Name Pins I/O Alternate Name Primary Function Alternate Function RD 1 Output External Memory Read None None ENV0 1 I/O Special mode select input with internal pull-up during reset PLLCLK PLL Clock Output ENV1 1 I/O Special mode select input with internal pull-up during reset CPUCLK CPU Clock Output ENV2 1 I/O Special mode select input with internal pull-up during reset SLOWCLK Slow Clock Output Table 5 CP3BT10 Pin Descriptions for the 48-Pin CSP Name Pins I/O Alternate Name Primary Function Alternate Function X1CKI 1 Input 12 MHz Oscillator Input BBCLK BB reference clock for the RF Interface X1CKO 1 Output 12 MHz Oscillator Output None None X2CKI 1 Input 32 kHz Oscillator Input None None X2CKO 1 Output 32 kHz Oscillator Output None None AVCC 1 Input PLL Analog Power Supply None None IOVCC 2 Input 2.5V - 3.3V I/O Power Supply None None VCC 2 Input 2.5V Core Logic Power Supply None None GND 4 Input Reference Ground None None AGND 1 Input PLL Analog Ground None None RESET 1 Input Chip general reset None None TMS 1 Input JTAG Test Mode Select (with internal weak pull-up) None None TDI 1 Input JTAG Test Data Input (with internal weak pull-up) None None TDO 1 Output JTAG Test Data Output None None TCK 1 Input JTAG Test Clock Input (with internal weak pull-up) None None RDY 1 Output NEXUS Ready Output None None RXD UART Receive Data Input PG0 1 I/O Generic I/O WUI10 Multi-Input Wake-Up Channel 10 TXD UART Transmit Data Output WUI11 Multi-Input Wake-Up Channel 11 RTS UART Ready-To-Send Output WUI12 Multi-Input Wake-Up Channel 12 CTS UART Clear-To-Send Input WUI13 Multi-Input Wake-Up Channel 13 SRFS AAI Receive Frame Sync NMI Non-Maskable Interrupt Input PG1 PG2 PG3 PG5 1 1 1 1 www.national.com I/O I/O I/O I/O Generic I/O Generic I/O Generic I/O Generic I/O 14 PH0 PH1 PH2 PH3 PH4 PH5 PH6 PH7 Pins 1 1 1 1 1 1 1 1 I/O I/O I/O I/O I/O I/O I/O I/O I/O Alternate Name Primary Function Alternate Function MSK SPI Shift Clock TIO1 Versatile Timer Channel 1 MDIDO SPI Master In Slave Out TIO2 Versatile Timer Channel 2 MDODI SPI Master Out Slave In TIO3 Versatile Timer Channel 3 MWCS SPI Slave Select Input TIO4 Versatile Timer Channel 4 SCK AAI Clock TIO5 Versatile Timer Channel 5 SFS AAI Frame Synchronization TIO6 Versatile Timer Channel 6 STD AAI Transmit Data Output TIO7 Versatile Timer Channel 7 SRD AAI Receive Data Input TIO8 Versatile Timer Channel 8 Generic I/O Generic I/O Generic I/O Generic I/O Generic I/O Generic I/O Generic I/O Generic I/O RFDATA 1 I/O Bluetooth RX/TX Data Pin None None PI0 1 I/O Generic I/O RFSYNC BT AC Correlation/TX Enable Output PI1 1 I/O Generic I/O RFCE BT RF Chip Enable Output BTSEQ1 Bluetooth Sequencer Status PI2 1 I/O Generic I/O SRCLK AAI Receive Clock PI3 1 I/O Generic I/O SCLK BT Serial I/F Shift Clock Output PI4 1 I/O Generic I/O SDAT BT Serial I/F Data PI5 1 I/O Generic I/O SLE BT Serial I/F Load Enable Output WUI9 Multi-Input Wake-Up Channel 9 PI6 1 I/O Generic I/O BTSEQ2 Bluetooth Sequencer Status TA Multi Function Timer Port A BTSEQ3 Bluetooth Sequencer Status PI7 1 I/O Generic I/O D+ 1 I/O USB D+ Upstream Port None None D- 1 I/O USB D- Upstream Port None None UVCC 1 Input 3.3V USB Transceiver Supply None None UGND 1 Input USB Transceiver Ground None None ENV0 1 I/O Special mode select input with internal pull-up during reset PLLCLK PLL Clock Output ENV1 1 I/O Special mode select input with internal pull-up during reset CPUCLK CPU Clock Output 15 www.national.com CP3BT10 Name CP3BT10 5.0 CPU Architecture The CP3BT10 uses the CR16C third-generation 16-bit CompactRISC processor core. The CPU implements a Reduced Instruction Set Computer (RISC) architecture that allows an effective execution rate of up to one instruction per clock cycle. For a detailed description of the CPU16C architecture, see the CompactRISC CR16C Programmer’s Reference Manual which is available on the National Semiconductor web site (http://www.nsc.com). The CR16C CPU core includes these internal registers: General-purpose registers (R0-R13, RA, and SP) Dedicated address registers (PC, ISP, USP, and INTBASE) Processor Status Register (PSR) Configuration Register (CFG) The R0-R11, PSR, and CFG registers are 16 bits wide. The R12, R13, RA, SP, ISP and USP registers are 32 bits wide. The PC register is 24 bits wide. Figure 1 shows the CPU registers. Dedicated Address Registers 15 0 23 31 PC ISPH ISPL USPH USPL INTBASEH INTBASEL Configuration Register 15 0 CFG 31 With the recommended calling convention for the architecture, some of these registers are assigned special hardware and software functions. Registers R0 to R13 are for generalpurpose use, such as holding variables, addresses, or index values. The SP register holds a pointer to the program runtime stack. The RA register holds a subroutine return address. The R12 and R13 registers are available to hold base addresses used in the index addressing mode. If a general-purpose register is specified by an operation that is 8 bits long, only the lower byte of the register is used; the upper part is not referenced or modified. Similarly, for word operations on register pairs, only the lower word is used. The upper word is not referenced or modified. 5.2 General-Purpose Registers 15 0 Processor Status Register 15 0 PSR When the CFG.SR bit is clear, register pairs are grouped in the manner used by native CR16C software: (R1,R0), (R2,R1) ... (R11,R10), (R12_L, R11), R12, R13, RA, SP. R12, R13, RA, and SP are 32-bit registers for holding addresses greater than 16 bits. DEDICATED ADDRESS REGISTERS R0 R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R13 The CR16C has four dedicated address registers to implement specific functions: the PC, ISP, USP, and INTBASE registers. RA SP 5.2.2 5.2.1 Program Counter (PC) Register The 24-bit value in the PC register points to the first byte of the instruction currently being executed. CR16C instructions are aligned to even addresses, therefore the least significant bit of the PC is always 0. At reset, the PC is initialized to 0 or an optional predetermined value. When a warm reset occurs, value of the PC prior to reset is saved in the (R1,R0) general-purpose register pair. Interrupt Stack Pointer (ISP) The 32-bit ISP register points to the top of the interrupt stack. This stack is used by hardware to service exceptions (interrupts and traps). The stack pointer may be accessed Figure 1. CPU Registers as the ISP register for initialization. The interrupt stack can Some register bits are designated as “reserved.” Software be located anywhere in the CPU address space. The ISP must write a zero to these bit locations when it writes to the cannot be used for any purpose other than the interrupt register. Read operations from reserved bit locations return stack, which is used for automatic storage of the CPU registers when an exception occurs and restoration of these undefined values. registers when the exception handler returns. The interrupt 5.1 GENERAL-PURPOSE REGISTERS stack grows downward in memory. The least significant bit The CompactRISC CPU features 16 general-purpose regis- and the 8 most significant bits of the ISP register are always ters. These registers are used individually as 16-bit oper- 0. ands or as register pairs for operations on addresses 5.2.3 User Stack Pointer (USP) greater than 16 bits. The USP register points to the top of the user-mode pro General-purpose registers are defined as R0 through gram stack. Separate stacks are available for user and suR13, RA, and SP. pervisor modes, to support protection mechanisms for Registers are grouped into pairs based on the setting of multitasking software. The processor mode is controlled by the Short Register bit in the Configuration Register the U bit in the PSR register (which is called PSR.U in the (CFG.SR). When the CFG.SR bit is set, the grouping of shorthand convention). Stack grow downward in memory. If register pairs is upward-compatible with the architecture the USP register points to an illegal address (any address of the earlier CR16A/B CPU cores: (R1,R0), (R2,R1) ... greater than 0x00FF_FFFF) and the USP is used for stack (R11,R10), (R12_L, R11), (R13_L, R12_L), (R14_L, access, an IAD trap is taken. R13_L) and SP. (R14_L, R13_L) is the same as (RA,ERA). DS004 www.national.com 16 Interrupt Base Register (INTBASE) N The INTBASE register holds the address of the dispatch table for exceptions. The dispatch table can be located anywhere in the CPU address space. When loading the INTBASE register, bits 31 to 24 and bit 0 must written with 0. 5.3 PROCESSOR STATUS REGISTER (PSR) E The PSR provides state information and controls operating modes for the CPU. The format of the PSR is shown below. 15 12 11 10 9 Reserved C T L U F Z I P E 8 7 6 5 4 3 2 0 N Z F 0 U L 1 0 T C The Carry bit indicates whether a carry or borrow occurred after addition or subtraction. 0 – No carry or borrow occurred. 1 – Carry or borrow occurred. The Trace bit enables execution tracing, in which a Trace trap (TRC) is taken after every instruction. Tracing is automatically disabled during the execution of an exception handler. 0 – Tracing disabled. 1 – Tracing enabled. The Low bit indicates the result of the last comparison operation, with the operands interpreted as unsigned integers. 0 – Second operand greater than or equal to first operand. 1 – Second operand less than first operand. The User Mode bit controls whether the CPU is in user or supervisor mode. In supervisor mode, the SP register is used for stack operations. In user mode, the USP register is used instead. User mode is entered by executing the Jump USR instruction. When an exception is taken, the exception handler automatically begins execution in supervisor mode. The USP register is accessible using the Load Processor Register (LPR/LPRD) instruction in supervisor mode. In user mode, an attempt to access the USP register generates a UND trap. 0 – CPU is executing in supervisor mode. 1 – CPU is executing in user mode. The Flag bit is a general condition flag for signalling exception conditions or distinguishing the results of an instruction, among other thing uses. For example, integer arithmetic instructions use the F bit to indicate an overflow condition after an addition or subtraction operation. The Zero bit is used by comparison operations. In a comparison of integers, the Z bit is set if the two operands are equal. If the operands are unequal, the Z bit is cleared. 0 – Source and destination operands unequal. 1 – Source and destination operands equal. P I The Negative bit indicates the result of the last comparison operation, with the operands interpreted as signed integers. 0 – Second operand greater than or equal to first operand. 1 – Second operand less than first operand. The Local Maskable Interrupt Enable bit enables or disables maskable interrupts. If this bit and the Global Maskable Interrupt Enable (I) bit are both set, all interrupts are enabled. If either of these bits is clear, only the nonmaskable interrupt is enabled. The E bit is set by the Enable Interrupts (EI) instruction and cleared by the Disable Interrupts (DI) instruction. 0 – Maskable interrupts disabled. 1 – Maskable interrupts enabled. The Trace Trap Pending bit is used together with the Trace (T) bit to prevent a Trace (TRC) trap from occurring more than once for one instruction. At the beginning of the execution of an instruction, the state of the T bit is copied into the P bit. If the P bit remains set at the end of the instruction execution, the TRC trap is taken. 0 – No trace trap pending. 1 – Trace trap pending. The Global Maskable Interrupt Enable bit is used to enable or disable maskable interrupts. If this bit and the Local Maskable Interrupt Enable (E) bit are both set, all maskable interrupts are taken. If either bit is clear, only the non-maskable interrupt is taken. Unlike the E bit, the I bit is automatically cleared when an interrupt occurs and automatically set upon completion of an interrupt handler. 0 – Maskable interrupts disabled. 1 – Maskable interrupts enabled. Bits Z, C, L, N, and F of the PSR are referenced from assembly language by the condition code in conditional branch instructions. A conditional branch instruction may cause a branch in program execution, based on the value of one or more of these PSR bits. For example, one of the Bcond instructions, BEQ (Branch EQual), causes a branch if the PSR.Z bit is set. On reset, bits 0 through 11 of the PSR are cleared, except for the PSR.E bit, which is set. On warm reset, the values of each bit before reset are copied into the R2 general-purpose register. Bits 4 and 8 of the PSR have a constant value of 0. Bits 12 through 15 are reserved. In general, status bits are modified only by specific instructions. Otherwise, status bits maintain their values throughout instructions which do not implicitly affect them. 17 www.national.com CP3BT10 5.2.4 CP3BT10 5.4 CONFIGURATION REGISTER (CFG) The CFG register is used to enable or disable various operating modes and to control optional on-chip caches. Because the CP3BT10 does not have cache memory, the cache control bits in the CFG register are reserved. All CFG bits are cleared on reset. 15 10 9 Reserved ED SR 8 7 6 SR ED 0 0 5 2 Reserved 1 0 0 0 The Extended Dispatch bit selects whether the size of an entry in the interrupt dispatch table (IDT) is 16 or 32 bits. Each entry holds the address of the appropriate exception handler. When the IDT has 16-bit entries, and all exception handlers must reside in the first 128K of the address space. The location of the IDT is held in the INTBASE register, which is not affected by the state of the ED bit. 0 – Interrupt dispatch table has 16-bit entries. 1 – Interrupt dispatch table has 32-bit entries. The Short Register bit enables a compatibility mode for the CR16B large model. In the CR16C core, registers R12, R13, and RA are extended to 32 bits. In the CR16B large model, only the lower 16 bits of these registers are used, and these “short registers” are paired together for 32-bit operations. In this mode, the (RA, R13) register pair is used as the extended RA register, and address displacements relative to a single register are supported with offsets of 0 and 14 bits in place of the index addressing with these displacements. 0 – 32-bit registers are used. 1 – 16-bit registers are used (CR16B mode). www.national.com 18 ADDRESSING MODES The CR16C CPU core implements a load/store architecture, in which arithmetic and logical instructions operate on register operands. Memory operands are made accessible in registers using load and store instructions. For efficient implementation of I/O-intensive embedded applications, the architecture also provides a set of bit operations that operate on memory operands. The load and store instructions support these addressing modes: register/pair, immediate, relative, absolute, and index addressing. When register pairs are used, the lower bits are in the lower index register and the upper bits are in the higher index register. When the CFG.SR bit is clear, the 32bit registers R12, R13, RA, and SP are also treated as register pairs. Index Mode References to register pairs in assembly language use parentheses. With a register pair, the lower numbered register pair must be on the right. For example, jump (r5, r4) For relative mode operands, the memory address is calculated by adding the value of a register pair and a displacement to the base address. The displacement can be a 14 or 20-bit unsigned value, which is encoded in the instruction. For absolute mode operands, the memory address is calculated by adding a 20-bit absolute address encoded in the instruction to the base address. load $4(r4,r3), (r6,r5) load $5(r12), (r13) The instruction set supports the following addressing modes: In register/pair mode, the operand is held in a general-purpose register, or in a general-purpose register pair. For example, the following instruction adds the contents of the low byte of register r1 to the contents of the low byte of r2, and places the result in the low byte register r2. The high byte of register r2 is not modified. ADDB R1, R2 Immediate In immediate mode, the operand is a conMode stant value which is encoded in the instruction. For example, the following instruction multiplies the value of r4 by 4 and places the result in r4. MULW $4, R4 Relative Mode In relative mode, the operand is addressed using a relative value (displacement) encoded in the instruction. This displacement is relative to the current Program Counter (PC), a general-purpose register, or a register pair. Register/Pair Mode In branch instructions, the displacement is always relative to the current value of the PC Register. For example, the following instruction causes an unconditional branch to an address 10 ahead of the current PC. BR *+10 In another example, the operand resides in memory. Its address is obtained by adding a displacement encoded in the instruction to the contents of register r5. The address calculation does not modify the contents of register r5. LOADW 12(R5), R6 The following example calculates the address of a source operand by adding a displacement of 4 to the contents of a register pair (r5, r4) and loads this operand into the register pair (r7, r6). r7 receives the high word of the operand, and r6 receives the low word. LOADD 4(r5, r4), (r7, r6) In index mode, the operand address is calculated with a base address held in either R12 or R13. The CFG.SR bit must be clear to use this mode. In the following example, the operand address is the sum of the displacement 4, the contents of the register pair (r5,r4), and the base address held in register r12. The word at this address is loaded into register r6. LOADW [r12]4(r5, r4), r6 Absolute Mode In absolute mode, the operand is located in memory, and its address is encoded in the instruction (normally 20 or 24 bits). For example, the following instruction loads the byte at address 4000 into the lower 8 bits of register r6. LOADB 4000, r6 For additional information on the addressing modes, see the CompactRISC CR16C Programmer's Reference Manual. 19 www.national.com CP3BT10 5.5 CP3BT10 5.6 STACKS 5.7 A stack is a last-in, first-out data structure for dynamic storage of data and addresses. A stack consists of a block of memory used to hold the data and a pointer to the top of the stack. As more data is pushed onto a stack, the stack grows downward in memory. The CR16C supports two types of stacks: the interrupt stack and program stacks. INSTRUCTION SET Table 6 lists the operand specifiers for the instruction set, and Table 7 is a summary of all instructions. For each instruction, the table shows the mnemonic and a brief description of the operation performed. In the mnemonic column, the lower-case letter “i” is used to indicate the type of integer that the instruction operates on, either “B” for byte or “W” for word. For example, the notation 5.6.1 Interrupt Stack ADDi for the “add” instruction means that there are two The processor uses the interrupt stack to save and restore forms of this instruction, ADDB and ADDW, which operate the program state during the exception handling. Hardware on bytes and words, respectively. automatically pushes this data onto the interrupt stack before entering an exception handler. When the exception Similarly, the lower-case string “cond” is used to indicate the handler returns, hardware restores the processor state with type of condition tested by the instruction. For example, the data popped from the interrupt stack. The interrupt stack notation Jcond represents a class of conditional jump instructions: JEQ for Jump on Equal, JNE for Jump on Not pointer is held in the ISP register. Equal, etc. For detailed information on all instructions, see 5.6.2 Program Stack the CompactRISC CR16C Programmer's Reference ManuThe program stack is normally used by software to save and al. restore register values on subroutine entry and exit, hold loTable 6 Key to Operand Specifiers cal and temporary variables, and hold parameters passed between the calling routine and the subroutine. The only Operand Specifier Description hardware mechanisms which operate on the program stack are the PUSH, POP, and POPRET instructions. abs Absolute address 5.6.3 User and Supervisor Stack Pointers To support multitasking operating systems, support is provided for two program stack pointers: a user stack pointer and a supervisor stack pointer. When the PSR.U bit is clear, the SP register is used for all program stack operations. This is the default mode when the user/supervisor protection mechanism is not used, and it is the supervisor mode when protection is used. When the PSR.U bit is set, the processor is in user mode, and the USP register is used as the program stack pointer. User mode can only be entered using the JUSR instruction, which performs a jump and sets the PSR.U bit. User mode is exited when an exception is taken and re-entered when the exception handler returns. In user mode, the LPRD instruction cannot be used to change the state of processor registers (such as the PSR). www.national.com 20 disp Displacement (numeric suffix indicates number of bits) imm Immediate operand (numeric suffix indicates number of bits) Iposition Bit position in memory Rbase Base register (relative mode) Rdest Destination register Rindex Index register RPbase, RPbasex Base register pair (relative mode) RPdest Destination register pair RPlink Link register pair Rposition Bit position in register Rproc 16-bit processor register Rprocd 32-bit processor register RPsrc Source register pair RPtarget Target register pair Rsrc, Rsrc1, Rsrc2 Source register CP3BT10 Table 7 Instruction Set Summary Mnemonic Operands Description MOVi Rsrc/imm, Rdest Move MOVXB Rsrc, Rdest Move with sign extension MOVZB Rsrc, Rdest Move with zero extension MOVXW Rsrc, RPdest Move with sign extension MOVZW Rsrc, RPdest Move with zero extension MOVD imm, RPdest Move immediate to register-pair RPsrc, RPdest Move between register-pairs ADD[U]i Rsrc/imm, Rdest Add ADDCi Rsrc/imm, Rdest Add with carry ADDD RPsrc/imm, RPdest Add with RP or immediate. MACQWa Rsrc1, Rsrc2, RPdest Multiply signed Q15: RPdest := RPdest + (Rsrc1 × Rsrc2) MACSWa Rsrc1, Rsrc2, RPdest Multiply signed and add result: RPdest := RPdest + (Rsrc1 × Rsrc2) MACUWa Rsrc1, Rsrc2, RPdest Multiply unsigned and add result: RPdest := RPdest + (Rsrc1 × Rsrc2) MULi Rsrc/imm, Rdest Multiply: Rdest(8) := Rdest(8) × Rsrc(8)/imm Rdest(16) := Rdest(16) × Rsrc(16)/imm MULSB Rsrc, Rdest Multiply: Rdest(16) := Rdest(8) × Rsrc(8) MULSW Rsrc, RPdest Multiply: RPdest := RPdest(16) × Rsrc(16) MULUW Rsrc, RPdest Multiply: RPdest := RPdest(16) × Rsrc(16); SUBi Rsrc/imm, Rdest Subtract: (Rdest := Rdest - Rsrc/imm) SUBD RPsrc/imm, RPdest Subtract: (RPdest := RPdest - RPsrc/imm) SUBCi Rsrc/imm, Rdest Subtract with carry: (Rdest := Rdest - Rsrc/imm) CMPi Rsrc/imm, Rdest Compare Rdest - Rsrc/imm CMPD RPsrc/imm, RPdest Compare RPdest - RPsrc/imm BEQ0i Rsrc, disp Compare Rsrc to 0 and branch if EQUAL BNE0i Rsrc, disp Compare Rsrc to 0 and branch if NOT EQUAL ANDi Rsrc/imm, Rdest Logical AND: Rdest := Rdest & Rsrc/imm ANDD RPsrc/imm, RPdest Logical AND: RPdest := RPsrc & RPsrc/imm ORi Rsrc/imm, Rdest Logical OR: Rdest := Rdest | Rsrc/imm ORD RPsrc/imm, RPdest Logical OR: Rdest := RPdest | RPsrc/imm Scond Rdest Save condition code as boolean XORi Rsrc/imm, Rdest Logical exclusive OR: Rdest := Rdest ^ Rsrc/imm XORD RPsrc/imm, RPdest Logical exclusive OR: Rdest := RPdest ^ RPsrc/imm ASHUi Rsrc/imm, Rdest Arithmetic left/right shift 21 www.national.com CP3BT10 Table 7 Instruction Set Summary Mnemonic Operands Description ASHUD Rsrc/imm, RPdest Arithmetic left/right shift LSHi Rsrc/imm, Rdest Logical left/right shift LSHD Rsrc/imm, RPdest Logical left/right shift SBITi Iposition, disp(Rbase) Set a bit in memory (Because this instruction treats the destination as a readmodify-write operand, it not be used to set bits in writeonly registers.) Iposition, disp(RPbase) Iposition, (Rindex)disp(RPbasex) Iposition, abs Iposition, (Rindex)abs CBITi Iposition, disp(Rbase) Clear a bit in memory Iposition, disp(RPbase) Iposition, (Rindex)disp(RPbasex) Iposition, abs Iposition, (Rindex)abs TBIT TBITi Rposition/imm, Rsrc Test a bit in a register Test a bit in memory Iposition, disp(Rbase) Iposition, disp(RPbase) Iposition, (Rindex)disp(RPbasex) Iposition, abs Iposition, (Rindex)abs LPR Rsrc, Rproc Load processor register LPRD RPsrc, Rprocd Load double processor register SPR Rproc, Rdest Store processor register SPRD Rprocd, RPdest Store 32-bit processor register Bcond disp9 Conditional branch disp17 disp24 BAL RPlink, disp24 Branch and link BR disp9 Branch disp17 disp24 EXCP vector Trap (vector) Jcond RPtarget Conditional Jump to a large address JAL RA, RPtarget, Jump and link to a large address RPlink, RPtarget JUMP RPtarget Jump JUSR RPtarget Jump and set PSR.U www.national.com 22 CP3BT10 Table 7 Instruction Set Summary Mnemonic Operands Description RETX Return from exception PUSH imm, Rsrc, RA Push “imm” number of registers on user stack, starting with Rsrc and possibly including RA POP imm, Rdest, RA Restore “imm” number of registers from user stack, starting with Rdest and possibly including RA POPRET imm, Rdest, RA Restore registers (similar to POP) and JUMP RA LOADi disp(Rbase), Rdest Load (register relative) abs, Rdest Load (absolute) (Rindex)abs, Rdest Load (absolute index relative) (Rindex)disp(RPbasex), Rdest Load (register relative index) disp(RPbase), Rdest Load (register pair relative) disp(Rbase), Rdest Load (register relative) abs, Rdest Load (absolute) (Rindex)abs, Rdest Load (absolute index relative) (Rindex)disp(RPbasex), Rdest Load (register pair relative index) disp(RPbase), Rdest Load (register pair relative) Rsrc, disp(Rbase) Store (register relative) Rsrc, disp(RPbase) Store (register pair relative) Rsrc, abs Store (absolute) Rsrc, (Rindex)disp(RPbasex) Store (register pair relative index) Rsrc, (Rindex)abs Store (absolute index) RPsrc, disp(Rbase) Store (register relative) RPsrc, disp(RPbase) Store (register pair relative) RPsrc, abs Store (absolute) RPsrc, (Rindex)disp(RPbasex) Store (register pair index relative) RPsrc, (Rindex)abs Store (absolute index relative) imm4, disp(Rbase) Store unsigned 4-bit immediate value extended to operand length in memory LOADD STORi STORD STOR IMM imm4, disp(RPbase) imm4, (Rindex)disp(RPbasex) imm4, abs imm4, (Rindex)abs LOADM imm3 Load 1 to 8 registers (R2-R5, R8-R11) from memory starting at (R0) LOADMP imm3 Load 1 to 8 registers (R2-R5, R8-R11) from memory starting at (R1, R0) STORM STORM imm3 Store 1 to 8 registers (R2-R5, R8-R11) to memory starting at (R2) 23 www.national.com CP3BT10 Table 7 Instruction Set Summary Mnemonic STORMP Operands Description imm3 Store 1 to 8 registers (R2-R5, R8-R11) to memory starting at (R7,R6) DI Disable maskable interrupts EI Enable maskable interrupts EIWAIT Enable maskable interrupts and wait for interrupt NOP No operation WAIT Wait for interrupt www.national.com 24 Memory The CP3BT10 supports a uniform 16M-byte linear address space. Table 8 lists the types of memory and peripherals that occupy this memory space. Unlisted address ranges Table 8 6.1 are reserved and must not be read or written. The BIU zones are regions of the address space that share the same control bits in the Bus Interface Unit (BIU). CP3BT10 Memory Map Start Address End Address Size in Bytes 00 0000h 03 FFFFh 256K On-chip Flash Program Memory, including Boot Memory 04 0000h 0D FFFFh 640K Reserved 0E 0000h 0E 1FFFh 8K On-chip Flash Data Memory 0E 2000h 0E 7FFFh 24K Reserved 0E 8000h 0E 91FFh 4.5K Bluetooth Data RAM 0E 9200h 0E BFFFh 11.5K Reserved 0E C000h 0E E7FFh 10K System RAM 0E E800h 0E EBFFh 1K Bluetooth Lower Link Controller Sequencer RAM 0E EC00h 0E EFFFh 1K Reserved 0E F000h 0E F0FFh 320 Reserved 0E F140h 0E F17Fh 64 Reserved 0E F180h 0E F1FFh 128 Bluetooth Lower Link Controller Registers 0E F200h 0F FFFFh 67.5K Reserved 10 0000h 3F FFFFh 3072K Reserved 40 0000h 7F FFFFh 4096K External Memory Zone 1 Static Zone 1 80 0000h FE FFFFh 8128K External Memory Zone 2 Static Zone 2 FF 0000h FF FAFFh 64256 BIU Peripherals FF FB00h FF FBFFh 256 I/O Expansion I/O Zone FF FC00h FF FFFFh 1K Peripherals and Other I/O Ports N/A Description OPERATING ENVIRONMENT The operating environment controls whether external memory is supported and whether the reset vector jumps to a code space intended to support In-System Programming (ISP). Up to 12M of external memory space is available. BIU Zone Static Zone 0 (mapped internally in IRE and ERE mode; mapped to the external bus in DEV mode) N/A gard to the states of the EMPTY bits. See Section 8.4.2 for more details. In the DEV environment, the on-chip flash memory is disabled, and the corresponding region of the address space is mapped to external memory. The operating mode of the device is controlled by the states on the ENV[2:0] pins at reset and the states of the EMPTY bits in the Protection Word, as shown in Table 9. Internal pullups on the ENV[2:0] pins select IRE mode or ISP mode if these pins are allowed to float. When ENV[2:0] = 111b, IRE mode is selected unless the EMPTY bits in the Protection word indicate that the program flash memory is empty (unprogrammed), in which case ISP mode is selected. When ENV[2:0] = 011b, ERE mode is selected unless the EMPTY bits indicate that the program flash memory is empty, in which case ISP mode is selected. When ENV[2:0] = 110b, ISP mode is selected without re- 25 Table 9 Operating Environment Selection ENV[2:0] EMPTY Operating Environment 111 No Internal ROM enabled (IRE) mode 011 No External ROM enabled (ERE) mode 000 N/A Development (DEV) mode 110 N/A In-System-Programming (ISP) mode 111 Yes In-System-Programming (ISP) mode 011 Yes In-System-Programming (ISP) mode www.national.com CP3BT10 6.0 CP3BT10 6.2 BUS INTERFACE UNIT (BIU) 6.4 The BIU controls the interface between the CPU core bus and those on-chip modules which are mapped into BIU zones. These on-chip modules are the flash program memory and the I/O zone. The BIU controls the configured parameters for bus access (such as the number of wait states for memory access) and issues the appropriate bus signals for the requested access. 6.3 BUS CYCLES There are four types of data transfer bus cycles: BIU CONTROL REGISTERS The BIU has a set of control registers that determine how many wait cycles and hold cycles are to be used for accessing memory. During initialization of the system, these registers should be programmed with appropriate values so that the minimum allowable number of cycles is used. This number varies with the clock frequency. There are five BIU control registers, as listed in Table 10. These registers control the bus cycle configuration used for accessing the various on-chip memory types. Table 10 Bus Control Registers Normal read Fast read Early write Late write The type of data cycle used in a particular transaction depends on the type of CPU operation (a write or a read), the type of memory or I/O being accessed, and the access type programmed into the BIU control registers (early/late write or normal/fast read). For read operations, a basic normal read takes two clock cycles, and a fast-read bus cycle takes one clock cycle. Normal read bus cycles are enabled by default after reset. Name Address Description BCFG FF F900h BIU Configuration Register IOCFG FF F902h I/O Zone Configuration Register SZCFG0 FF F904h Static Zone 0 Configuration Register SZCFG1 FF F906h Static Zone 1 Configuration Register Static Zone 2 For write operations, a basic late-write bus cycle takes two SZCFG2 FF F908h Configuration Register clock cycles, and a basic early-write bus cycle takes three clock cycles. Early-write bus cycles are enabled by default BIU Configuration Register (BCFG) after reset. However, late-write bus cycles are needed for 6.4.1 ordinary write operations, so this configuration must be The BCFG register is a byte-wide, read/write register that changed by software (see Section 6.4.1). selects early-write or late-write bus cycles. At reset, the regIn certain cases, one or more additional clock cycles are ister is initialized to 07h. The register format is shown below. added to a bus access cycle. There are two types of additional clock cycles for ordinary memory accesses, called in7 3 2 1 0 ternal wait cycles (TIW) and hold (Thold) cycles. Reserved 1 1 EWR A wait cycle is inserted in a bus cycle just after the memory address has been placed on the address bus. This gives the accessed memory more time to respond to the transaction EWR The Early Write bit controls write cycle timing. request. 0 – Late-write operation (2 clock cycles to A hold cycle is inserted at the end of a bus cycle. This holds write). the data on the data bus for an extended number of clock cy1 – Early-write operation. cles. At reset, the BCFG register is initialized to 07h, which selects early-write operation. However, late-write operation is required for normal device operation, so software must change the register value to 06h. Bits 1 and 2 of this register must always be set when writing to this register. www.national.com 26 I/O Zone Configuration Register (IOCFG) 6.4.3 The IOCFG register is a word-wide, read/write register that controls the timing and bus characteristics of accesses to the 256-byte I/O Zone memory space (FF FB00h to FF FBFFh). The registers associated with Port B and Port C reside in the I/O memory array. At reset, the register is initialized to 069Fh. The register format is shown below. 7 BW 6 5 Reserved 4 3 2 HOLD 15 The SZCFG0 register is a word-wide, read/write register that controls the timing and bus characteristics of Zone 0 memory accesses. Zone 0 is used for the on-chip flash memory (including the boot area, program memory, and data memory). At reset, the register is initialized to 069Fh. The register format is shown below. 0 WAIT 10 Reserved Static Zone 0 Configuration Register (SZCFG0) 9 8 IPST Res. 7 6 5 BW WBR RBE 15 HOLD BW IPST The Memory Wait Cycles field specifies the number of TIW (internal wait state) clock cycles added for each memory access, ranging from 000 binary for no additional TIW wait cycles to 111 binary for seven additional TIW wait cycles. The Memory Hold Cycles field specifies the number of Thold clock cycles used for each memory access, ranging from 00b for no Thold cycles to 11b for three Thold clock cycles. The Bus Width bit defines the bus width of the IO Zone. 0 – 8-bit bus width. 1 – 16-bit bus width (default) The Post Idle bit controls whether an idle cycle follows the current bus cycle, when the next bus cycle accesses a different zone. No idle cycles are required for on-chip accesses. 0 – No idle cycle (recommended). 1 – Idle cycle. WAIT HOLD RBE WBR BW FRE IPST 27 3 2 HOLD 12 Reserved WAIT 4 11 FRE 0 WAIT 10 9 IPRE IPST 8 Res. The Memory Wait field specifies the number of TIW (internal wait state) clock cycles added for each memory access, ranging from 000b for no additional TIW wait cycles to 111b for seven additional TIW wait cycles. These bits are ignored if the SZCFG0.FRE bit is set. The Memory Hold field specifies the number of Thold clock cycles used for each memory access, ranging from 00b for no Thold cycles to 11b for three Thold clock cycles. These bits are ignored if the SZCFG0.FRE bit is set. The Read Burst Enable enables burst cycles on 16-bit reads from 8-bit bus width regions of the address space. Because the flash program memory is required to be 16-bit bus width, the RBE bit is a don’t care bit. This bit is ignored when the SZCFG0.FRE bit is set. 0 – Burst read disabled. 1 – Burst read enabled. The Wait on Burst Read bit controls if a wait state is added on burst read transaction. This bit is ignored, when SZCFG0.FRE bit is set or when SZCFG0.RBE is clear. 0 – No TBW on burst read cycles. 1 – One TBW on burst read cycles. The Bus Width bit controls the bus width of the zone. The flash program memory must be configured for 16-bit bus width. 0 – 8-bit bus width. 1 – 16-bit bus width (required). The Fast Read Enable bit controls whether fast read bus cycles are used. A fast read operation takes one clock cycle. A normal read operation takes at least two clock cycles. 0 – Normal read cycles. 1 – Fast read cycles. The Post Idle bit controls whether an idle cycle follows the current bus cycle, when the next bus cycle accesses a different zone. No idle cycles are required for on-chip accesses. 0 – No idle cycle (recommended). 1 – Idle cycle inserted. www.national.com CP3BT10 6.4.2 CP3BT10 IPRE The Preliminary Idle bit controls whether an idle cycle is inserted prior to the current bus cycle, when the new bus cycle accesses a different zone. No idle cycles are required for onchip accesses. 0 – No idle cycle (recommended). 1 – Idle cycle inserted. 6.4.4 Static Zone 1 Configuration Register (SZCFG1) The SZCFG1 register is a word-wide, read/write register that controls the timing and bus characteristics for off-chip accesses selected with the SEL1 output signal. At reset, the register is initialized to 069Fh. The register format is shown below. 7 6 5 BW WBR RBE 15 HOLD RBE WBR BW FRE IPST IPRE www.national.com 28 3 2 HOLD 12 Reserved WAIT 4 11 FRE 0 WAIT 10 9 IPRE IPST 8 Res. The Memory Wait field specifies the number of TIW (internal wait state) clock cycles added for each memory access, ranging from 000b for no additional TIW wait cycles to 111b for seven additional TIW wait cycles. These bits are ignored if the SZCFG1.FRE bit is set. The Memory Hold field specifies the number of Thold clock cycles used for each memory access, ranging from 00b for no Thold cycles to 11b for three Thold clock cycles. These bits are ignored if the SZCFG1.FRE bit is set. The Read Burst Enable enables burst cycles on 16-bit reads from 8-bit bus width regions of the address space. This bit is ignored when the SZCFG1.FRE bit is set or the SZCFG1.BW is clear. 0 – Burst read disabled. 1 – Burst read enabled. The Wait on Burst Read bit controls if a wait state is added on burst read transaction. This bit is ignored, when SZCFG1.FRE bit is set or when SZCFG1.RBE is clear. 0 – No TBW on burst read cycles. 1 – One TBW on burst read cycles. The Bus Width bit controls the bus width of the zone. 0 – 8-bit bus width. 1 – 16-bit bus width. The Fast Read Enable bit controls whether fast read bus cycles are used. A fast read operation takes one clock cycle. A normal read operation takes at least two clock cycles. 0 – Normal read cycles. 1 – Fast read cycles. The Post Idle bit controls whether an idle cycle follows the current bus cycle, when the next bus cycle accesses a different zone. 0 – No idle cycle. 1 – Idle cycle inserted. The Preliminary Idle bit controls whether an idle cycle is inserted prior to the current bus cycle, when the new bus cycle accesses a different zone. 0 – No idle cycle. 1 – Idle cycle inserted. Static Zone 2 Configuration Register (SZCFG2) 6.5 WAIT AND HOLD STATES The SZCFG2 register is a word-wide, read/write register The number of wait cycles and hold cycles inserted into a that controls the timing and bus characteristics for off-chip bus cycle depends on whether it is a read or write operation, accesses selected with the SEL2 output signal. the type of memory or I/O being accessed, and the control At reset, the register is initialized to 069Fh. The register for- register settings. mat is shown below. 7 6 5 BW WBR RBE 15 HOLD RBE WBR BW FRE IPST IPRE 4 3 2 HOLD 12 Reserved WAIT 6.5.1 11 FRE When the CPU accesses the Flash program and data memory (address ranges 000000h–03FFFFh and 0E0000h– 0E1FFFh), the number of added wait and hold cycles depends on the type of access and the BIU register settings. 0 WAIT 10 9 IPRE IPST Flash Program/Data Memory In fast-read mode (SZCFG0.FRE=1), a read operation is a single cycle access. This limits the maximum CPU operating frequency to 24 MHz. 8 Res. For a read operation in normal-read mode (SZCFG0.FRE=0), the number of inserted wait cycles is The Memory Wait field specifies the number specified in the SZCFG0.WAIT field. The total number of of TIW (internal wait state) clock cycles added wait cycles is the value in the WAIT field plus 1, so it can for each memory access, ranging from 000b range from 1 to 8. The number of inserted hold cycles is for no additional TIW wait cycles to 111b for specified in the SCCFG0.HOLD field, which can range from seven additional TIW wait cycles. These bits 0 to 3. are ignored if the SZCFG2.FRE bit is set. For a write operation in fast read mode (SZCFG0.FRE=1), The Memory Hold field specifies the number the number of inserted wait cycles is 1. No hold cycles are of Thold clock cycles used for each memory used. access, ranging from 00b for no Thold cycles to 11b for three Thold clock cycles. These bits For a write operation normal read mode (SZCFG0.FRE=0), the number of wait cycles is equal to the value written to the are ignored if the SZCFG2.FRE bit is set. The Read Burst Enable enables burst cycles SZCFG0.WAIT field plus 1 (in the late write mode) or 2 (in on 16-bit reads from 8-bit bus width regions of the early write mode). The number of inserted hold cycles is the address space. This bit is ignored when equal to the value written to the SCCFG0.HOLD field, which the SZCFG2.FRE bit is set or the can range from 0 to 3. SZCFG2.BW is clear. 6.5.2 RAM Memory 0 – Burst read disabled. Read and write accesses to on-chip RAM is performed with1 – Burst read enabled. The Wait on Burst Read bit controls if a wait in a single cycle, without regard to the BIU settings. The state is added on burst read transaction. This RAM address is in the range of 0E 8000h–0E 91FFh and 0E bit is ignored, when SZCFG2.FRE bit is set or C000h–0E EBFFh. when SZCFG2.RBE is clear. 0 – No TBW on burst read cycles. 1 – One TBW on burst read cycles. The Bus Width bit controls the bus width of the zone. 0 – 8-bit bus width. 1 – 16-bit bus width. The Fast Read Enable bit controls whether fast read bus cycles are used. A fast read operation takes one clock cycle. A normal read operation takes at least two clock cycles. 0 – Normal read cycles. 1 – Fast read cycles. The Post Idle bit controls whether an idle cycle follows the current bus cycle, when the next bus cycle accesses a different zone. 0 – No idle cycle. 1 – Idle cycle inserted. The Preliminary Idle bit controls whether an idle cycle is inserted prior to the current bus cycle, when the new bus cycle accesses a different zone. 0 – No idle cycle. 1 – Idle cycle inserted. 6.5.3 Access to Peripherals When the CPU accesses on-chip peripherals in the range of 0E F000h–0E F1FFh and FF 0000h–FF FBFFh, one wait cycle and one preliminary idle cycle is used. No hold cycles are used. The IOCFG register determines the access timing for the address range FF FB00h–FF FBFFh. 29 www.national.com CP3BT10 6.4.5 CP3BT10 7.0 System Configuration Registers The system configuration registers control and provide status for certain aspects of device setup and operation, such as indicating the states sampled from the ENV[2:0] inputs. The system configuration registers are listed in Table 11. Table 11 System Configuration Registers 7.1 Name Address Description MCFG FF F910h Module Configuration Register MSTAT FF F914h Module Status Register MODULE CONFIGURATION REGISTER (MCFG) MISC_IO_SPEED The MISC_IO_SPEED bit controls the slew rate of the output drivers for the ENV[2:0], RDY, RFDATA, and TDO pins. To minimize noise, the slow slew rate is recommended. 0 – Fast slew rate. 1 – Slow slew rate. MEM_IO_SPEED The MEM_IO_SPEED bit controls the slew rate of the output drivers for the A[21:0], RD, SEL[2:1], and WR[1:0] pins. Memory speeds for the CP3BT10 are characterized with fast slew rate. Slow slew rate reduces the available memory access time by 5 ns. 0 – Fast slew rate. 1 – Slow slew rate. 7.2 The MCFG register is a byte-wide, read/write register that selects the clock output features of the device. The register must be written in active mode only, not in power save, HALT, or IDLE mode. However, the register contents are preserved during all power modes. The MCFG register format is shown below. MODULE STATUS REGISTER (MSTAT) The MSTAT register is a byte-wide, read-only register that indicates the general status of the device. The MSTAT register format is shown below. 7 5 4 3 2 1 0 Reserved DPGMBUSY PGMBUSY OENV2 OENV1 OENV0 The Operating Environment bits hold the states sampled from the ENV[2:0] input pins MEM_IO MISC_IO USB SCLK MCLK PLLCLK EXI Res. at reset. These states are controlled by exter_SPEED _SPEED _ENABLE OE OE OE OE nal hardware at reset and are held constant in the register until the next reset. PGMBUSY The Flash Programming Busy bit is automatiEXIOE The EXIOE bit controls whether the external cally set when either the program memory or bus is enabled in the IRE environment for imthe data memory is being programmed or plementing the I/O Zone (FF FB00h–FF erased. It is clear when neither of the memoFBFFh). ries is busy. When this bit is set, software must 0 – External bus disabled. not attempt to program or erase either of 1 – External bus enabled. these two memories. This bit is a copy of the PLLCLKOE The PLLCLKOE bit controls whether the PLL FMBUSY bit in the FMSTAT register. clock is driven on the ENV0/PLLCLK pin. 0 – Flash memory is not busy. 0 – ENV0/PLLCLK pin is high impedance. 1 – Flash memory is busy. 1 – PLL clock driven on ENV0/PLLCLK. DPGMBUSY The Data Flash Programming Busy indicates MCLKOE The MCLKOE bit controls whether the Main that the flash data memory is being erased or Clock is driven on the ENV1/CPUCLK pin. a pipelined programming sequence is current0 – ENV1/CPUCLK pin is high impedance. ly ongoing. Software must not attempt to per1 – Main Clock is driven on ENV1/CPUCLK. form any write access to the flash program SCLKOE The SCLKOE bit controls whether the Slow memory at this time, without also polling the Clock is driven on the ENV2/SLOWCLK pin. FSMSTAT.FMFULL bit in the flash memory in0 – ENV2/SLOWCLK pin is high impedance. terface. The DPGMBUSY bit is a copy of the 1 – Slow Clock driven on ENV2/SLOWCLK. FMBUSY bit in the FSMSTAT register. USB_ENABLE The USB_ENABLE bit can be used to force 0 – Flash data memory is not busy. an external USB transceiver into its low-power 1 – Flash data memory is busy. mode. The power mode is dependent on the USB controller status, the USB_ENABLE bit in the Function Word (see Section 8.4.1), and the USB_ENABLE bit in the MCFG register. 0 – External USB transceiver forced into lowpower mode. 1 – Transceiver power mode dependent on USB controller status and programming of the Function Word. (This is the state of the USB_ENABLE bit after reset.) 7 6 www.national.com 5 4 3 2 1 OENV[2:0] 0 30 Flash Memory The flash memory consists of the flash program memory and the flash data memory. The flash program memory is further divided into the Boot Area and the Code Area. default (after reset) all bits in the FM0WER, FM1WER, and FSM0WER registers are cleared, which disables write access by the CPU to all sections. Write access to a section is A special protection scheme is applied to the lower portion enabled by setting the corresponding write enable bit. After of the flash program memory, called the Boot Area. The completing a programming or erase operation, software Boot Area always starts at address 0 and ranges up to a should clear all write enable bits to protect the flash program programmable end address. The maximum boot area ad- memory against any unintended writes. dress which can be selected is 00 1BFFh. The intended use 8.1.2 Global Protection of this area is to hold In-System-Programming (ISP) rouThe WRPROT field in the Protection Word controls global tines or essential application routines. The Boot Area is alwrite protection. The Protection Word is located in a special ways protected against CPU write access, to avoid flash memory outside of the CPU address space. If a majorunintended modifications. ity of the bits in the 3-bit WRPROT field are clear, write proThe Code Area is intended to hold the application code and tection is enabled. Enabling this mode prevents the CPU constant data. The Code Area begins with the next byte af- from writing to flash memory. ter the Boot Area. Table 12 summarizes the properties of The RDPROT field in the Protection Word controls global the regions of flash memory mapped into the CPU address read protection. If a majority of the bits in the 3-bit RDPROT space. field are clear, read protection is enabled. Enabling this Table 12 Flash Memory Areas mode prevents reading by an external debugger through the serial debug interface or by an external flash programmer. Read Area Address Range Write Access CPU read access is not affected by the RDPROT bits. Access 8.2 Boot Area Code Area Data Area 8.1 0–BOOTAREA - 1 BOOTAREA–03 FFFFh 0E 0000h–0E 1FFFh Yes No Yes Write access only if section write enable bit is set and global write protection is disabled. Yes Write access only if section write enable bit is set and global write protection is disabled. Each of the flash memories are divided into main blocks and information blocks. The main blocks hold the code or data used by application software. The information blocks hold factory parameters, protection settings, and other devicespecific data. The main blocks are mapped into the CPU address space. The information blocks are accessed indirectly through a register-based interface. Separate sets of registers are provided for accessing flash program memory (FM registers) and flash data memory (FSM registers). The flash program memory consists of two main blocks and two data blocks, as shown in Table 13. The flash data memory consists of one main block and one information block. Table 13 Flash Memory Blocks Name Address Range Function Main Block 0 00 0000h–01 FFFFh (CPU address space) Flash Program Memory Information Block 0 000h–07Fh (address register) Function Word, Factory Parameters Main Block 1 02 0000h–03 FFFFh (CPU address space) Flash Program Memory Information Block 1 080h–0FFh (address register) Protection Word, User Data Main Block 2 0E 0000h–0E 1FFFh (CPU address space) Flash Data Memory FLASH MEMORY PROTECTION The memory protection mechanisms provide both global and section-level protection. Section-level protection against CPU writes is applied to individual 8K-byte sections of the flash program memory and 512-byte sections of the flash data memory. Section-level protection is controlled through read/write registers mapped into the CPU address space. Global write protection is applied at the device level, to disable flash memory writes by the CPU. Global write protection is controlled by the encoding of bits stored in the flash memory array. 8.1.1 FLASH MEMORY ORGANIZATION Section-Level Protection Information 000h–07Fh User Data (address register) Block 2 Each bit in the Flash Memory Write Enable (FM0WER and FM1WER) registers enables or disables write access to a corresponding section of flash program memory. Write ac- 8.2.1 Main Block 0 and 1 cess to the flash data memory is controlled by the bits in the Main Block 0 and Main Block 1 hold the 256K-byte program Flash Slave Memory Write Enable (FSM0WER) register. By space, which consists of the Boot Area and Code Area. 31 www.national.com CP3BT10 8.0 CP3BT10 Each block consists of sixteen 8K-byte sections. Write access by the CPU to Main Block 0 and Main Block 1 is controlled by the corresponding bits in the FM0WER and FM1WER registers, respectively. The least significant bit in each register controls the section at the lowest address. 8.2.2 Information Block 0 Information Block 0 contains 128 bytes, of which one 16-bit word has a dedicated function, called the Function Word. The Function Word resides at address 07Eh. It controls the power mode of an external USB transceiver. The remaining Information Block 0 locations are used to hold factory parameters. 8.2.5 Information Block 2 Information Block 2 contains 128 bytes, which can be used to store user data. The CPU can always read Information Block 2. The CPU can write Information Block 2 only when global write protection is disabled. Erasing Information Block 2 also erases Main Block 2. 8.3 FLASH MEMORY OPERATIONS Flash memory programming (erasing and writing) can be performed on the flash data memory while the CPU is executing out of flash program memory. Although the CPU can execute out of flash data memory, it cannot erase or write the flash program memory while executing from flash data Software only has read access to Information Block 0 memory. To erase or write the flash program memory, the through a register-based interface. The Function Word and CPU must be executing from the on-chip static RAM or offthe factory parameters are protected against CPU writes. chip memory. Table 14 shows the structure of Information Block 0. An erase operation is required before programming. An Table 14 Information Block 0 erase operation sets all of the bits in the erased region. A programming operation clears selected bits. Address Read The programming mechanism is pipelined, so that a new Name Write Access Range Access write request can be loaded while a previous request is in Function Word 07Eh–07Fh Other (Used for Factory Parameters) 000h–07Dh 8.2.3 Yes progress. When the FMFULL bit in the FMSTAT or FSMSTAT register is clear, the pipeline is ready to receive a new request. New requests may be loaded after checking only the FMFULL bit. No 8.3.1 Information Block 1 Information Block 1 contains 128 bytes, of which one 16-bit word has a dedicated function, called the Protection Word. The Protection Word resides at address 0FEh. It controls the global protection mechanisms and the size of the Boot Area. The Protection Word can be written by the CPU, however the changes only become valid after the next device reset. The remaining Information Block 1 locations can be used to store other user data. Erasing Information Block 1 also erases Main Block 1. Table 15 shows the structure of the Information Block 1. Table 15 Information Block 1 Name Address Range Protection Word 0FEh–0FFh Other (User Data) 8.2.4 080h–0FDh Read Access Write Access Yes Write access only if section write enable bit is set and global write protection is disabled. Main Block 2 holds the 8K-byte data area, which consists of sixteen 512-byte sections. Write access by the CPU to Main Block 2 is controlled by the corresponding bits in the FSM0WER register. The least significant bit in the register controls the section at the lowest address. 3. Set the Page Erase (PER) bit. The PER bit is in the FMwww.national.com Read accesses from flash program memory can only occur when the flash program memory is not busy from a previous write or erase operation. Read accesses from the flash data memory can only occur when both the flash program memory and the flash data memory are not busy. Both byte and word read operations are supported. 8.3.2 32 Information Block Read Information block data is read through the register-based interface. Only word read operations are supported and the read address must be word-aligned (LSB = 0). The following steps are used to read from an information block: 1. Load the word address in the Flash Memory Information Block Address (FMIBAR) or Flash Slave Memory Information Block Address (FSMIBAR) register. 2. Read the data word by reading out the Flash Memory Information Block Data (FMIBDR) or Flash Slave Memory Information Block Data (FSMIBDR) register. 8.3.3 Main Block 2 Main Block Read Main Block Page Erase A flash erase operation sets all of the bits in the erased region. Pages of a main block can be individually erased if their write enable bits are set. This method cannot be used to erase the boot area, if defined. Each page in Main Block 0 and 1 consists of 1024 bytes (512 words). Each page in Main Block 2 consists of 512 bytes (256 words). To erase a page, the following steps are performed: 1. Verify that the Flash Memory Busy (FMBUSY) bit is clear. The FMBUSY bit is in the FMSTAT or FSMSTAT register. 2. Prevent accesses to the flash memory while erasing is in progress. CTRL or FSMCTRL register. 8.3.4 2. Prevent accesses to the flash memory while the write is in progress. 3. Set the Program Enable (PE) bit. The PE bit is in the FMCTRL or FSMCTRL register. 4. Write a word to the desired word-aligned address. This starts a new pipelined programming sequence. The FMBUSY bit becomes set while the write operation is in progress. The FMFULL bit in the FMSTAT or FSMSTAT register becomes set if a previous write operation is still in progress. 5. Wait until the FMFULL bit becomes clear. 6. Repeat steps 4 and 5 for additional words. 7. Wait until the FMBUSY bit becomes clear again. 8. Check the programming error (PERR) bit to confirm successful programming. The PERR bit is in the FMSTAT or FSMSTAT register. 9. Clear the Program Enable (PE) bit. Main Block Module Erase A module erase operation can be used to erase an entire main block. All sections within the block must be enabled for writing. If a boot area is defined in the block, it cannot be erased. The following steps are performed to erase a main block: 1. Verify that the Flash Memory Busy (FMBUSY) bit is clear. The FMBUSY bit is in the FMSTAT or FSMSTAT register. 2. Prevent accesses to the flash memory while erasing is in progress. 3. Set the Module Erase (MER) bit. The MER bit is in the FMCTRL or FSMCTRL register. 4. Write to any address within the desired main block. 5. Wait until the FMBUSY bit becomes clear again. 6. Check the Erase Error (EERR) bit to confirm successful erase of the block. The EERR bit is in the FMSTAT or FSMSTAT register. 7. Clear the MER bit. 8.3.7 Information Block Write Writing is only allowed when global write protection is disabled. Writing by the CPU is only allowed when the write enable bit is set for the sector which contains the word to be written. The CPU cannot write Information Block 0. Only word-wide write access to word-aligned addresses is supported. The following steps are performed to write a word: 1. Verify that the Flash Memory Busy (FMBUSY) bit is clear. The FMBUSY bit is in the FMSTAT or FSMSTAT register. 8.3.5 Information Block Module Erase 2. Prevent accesses to the flash memory while the write Erasing an information block also erases the corresponding is in progress. main block. If a boot area is defined in the main block, nei- 3. Set the Program Enable (PE) bit. The PE bit is in the ther block can be erased. Page erase is not supported for FMCTRL or FSMCTRL register. information blocks. The following steps are performed to 4. Write the desired target address into the FMIBAR or erase an information block: FSMIBAR register. 1. Verify that the Flash Memory Busy (FMBUSY) bit is 5. Write the data word into the FMIBDR or FSMIBDR register. This starts a new pipelined programming seclear. The FMBUSY bit is in the FMSTAT or FSMSTAT quence. The FMBUSY bit becomes set while the write register. operation is in progress. The FMFULL bit in the FM2. Prevent accesses to the flash memory while erasing is STAT or FSMSTAT register becomes set if a previous in progress. write operation is still in progress. 3. Set the Module Erase (MER) bit. The MER bit is in the 6. Wait until the FMFULL bit becomes clear. FMCTRL or FSMCTRL register. 7. Repeat steps 4 through 6 for additional words. 4. Load the FMIBAR or FSMIBAR register with any address within the block, then write any data to the FMIB- 8. Wait until the FMBUSY bit becomes clear again. 9. Check the programming error (PERR) bit to confirm DR or FSMIBDR register. successful programming. The PERR bit is in the FM5. Wait until the FMBUSY bit becomes clear again. STAT or FSMSTAT register. 6. Check the Erase Error (EERR) bit to confirm successful erase of the block. The EERR bit is in the FMSTAT or 10. Clear the Program Enable (PE) bit. FSMSTAT register. 8.4 INFORMATION BLOCK WORDS 7. Clear the MER bit. Two words in the information blocks are dedicated to hold 8.3.6 Main Block Write settings that affect the operation of the system: the Function Writing is only allowed when global write protection is dis- Word in Information Block 0 and the Protection Word in Inabled. Writing by the CPU is only allowed when the write en- formation Block 1. able bit is set for the sector which contains the word to be 8.4.1 Function Word written. The CPU cannot write the Boot Area. Only wordwide write access to word-aligned addresses is supported. The Function Word resides in the Information Block 0 at address 07Eh. At reset, the Function Word is copied into the The following steps are performed to write a word: FMAR0 register. 1. Verify that the Flash Memory Busy (FMBUSY) bit is clear. The FMBUSY bit is in the FMSTAT or FSMSTAT 15 1 0 register. Reserved USB_ENABLE 33 www.national.com CP3BT10 4. Write to an address within the desired page. 5. Wait until the FMBUSY bit becomes clear again. 6. Check the Erase Error (EERR) bit to confirm successful erase of the page. The EERR bit is in the FMSTAT or FSMSTAT register. 7. Repeat steps 4 through 6 to erase additional pages. 8. Clear the PER bit. CP3BT10 USB_ENABLE The USB_ENABLE bit can be used to force an external USB transceiver into its low-power mode. The power mode is dependent on the USB controller status, the USB_ENABLE bit in the MCFG register (see Section 7.1), and the USB_ENABLE bit in the Function Word. 0 – External USB transceiver forced into lowpower mode. ISPE 1 – Transceiver power mode dependent on USB controller status and programming of the Function Word. 8.4.2 Protection Word The Protection Word resides in Information Block 1 at address 0FEh. At reset, the Protection Word is copied into the FMAR1 register. 15 13 12 10 9 7 WRPROT RDPROT ISPE 6 4 3 1 0 EMPTY BOOTAREA 1 ENV[1:0] inputs (see Section 6.1) are sampled high at reset and the EMPTY bits indicate the flash program memory is empty, the device will begin execution in ISP mode. The device enters ISP mode without regard to the EMPTY status if ENV0 is driven low and ENV1 is driven high. The ISPE field indicates whether the Boot Area is used to hold In-System-Programming routines or user application routines. If a majority of the three ISPE bits are set, the Boot Area holds ISP routines. If majority of the ISPE bits are clear, the Boot Area holds user application routines. Table 17 summarizes all possible EMPTY, ISPE, and Boot Area settings and the corresponding start-up operation for each combination. In DEV mode, the EMPTY bit settings are ignored and the CPU always starts executing from address 0. Table 17 CPU Reset Behavior BOOTAREA The BOOTAREA field specifies the size of the Boot Area. The Boot Area starts at address 0 and ends at the address specified by this field. The inverted bits of the BOOTAREA field count the number of 1024-byte blocks to be reserved as the Boot Area. The maximum Boot Area size is 7K bytes (address range 0 to 1BFFh). The end of the Boot Area defines the start of the Code Area. If the device starts in ISP mode and there is no Boot Area defined (encoding 111b), the device is kept in reset. Table 16 lists all possible boot area encodings. Table 16 Boot Area Encodings EMPTY EMPTY Boot Area Start-Up Operation ISP Defined Device starts in IRE/ ERE mode from Code Area start address Not Empty ISP Not Defined Device starts in IRE/ ERE mode from Code Area start address Not Empty No ISP Don’t Care Device starts in IRE/ ERE mode from address 0 Device starts in ISP mode from Code Area start address Not Empty ISPE BOOT AREA Size of the Boot Area Code Area Start Address Empty ISP Defined 111 No Boot Area defined 00 0000h Empty ISP Not Defined 110 1024 bytes 00 0400h Empty No ISP Don’t Care 101 2048 bytes 00 0800h 100 3072 bytes 00 0C00h 011 4096 bytes 00 1000h 010 5120 bytes 00 1400h 001 6144 bytes 00 1800h 000 7168 bytes 00 1C00h RDPROT The EMPTY field indicates whether the flash program memory has been programmed or should be treated as blank. If a majority of the three EMPTY bits are clear, the flash program memory is treated as programmed. If a majority of the EMPTY bits are set, the flash program memory is treated as empty. If the www.national.com 34 WRPROT Device starts in ISP mode and is kept in its reset state The RDPROT field controls the global read protection mechanism for the on-chip flash program memory. If a majority of the three RDPROT bits are clear, the flash program memory is protected against read access from the serial debug interface or an external flash programmer. CPU read access is not affected by the RDPROT bits. If a majority of the RDPROT bits are set, read access is allowed. The WRPROT field controls the global write protection mechanism for the on-chip flash program memory. If a majority of the three WRPROT bits are clear, the flash program memory is protected against write access from any source and read access from the se- 8.5 Table 18 Flash Memory Interface Registers FLASH MEMORY INTERFACE REGISTERS There is a separate interface for the program flash and data flash memories. The same set of registers exist in both interfaces. In most cases they are independent of each other, but in some cases the program flash interface controls the interface for both memories, as indicated in the following sections. Table 18 lists the registers. Table 18 Flash Memory Interface Registers Program Memory Data Memory Description FMIBAR FF F940h FSMIBAR FF F740h Flash Memory Information Block Address Register FMIBDR FF F942h FSMIBDR FF F742h Flash Memory Information Block Address Register FM0WER FF F944h FSM0WER FF F744h Flash Memory 0 Write Enable Register FM1WER FF F946h N/A Flash Memory 1 Write Enable Register FMCTRL FF F94Ch FSMCTRL FF F74Ch Flash Memory Control Register FMSTAT FF F94Eh FSMSTAT FF F74Eh Flash Memory Status Register FMPSR FF F950h FSMPSR FF F750h Flash Memory Prescaler Register FMSTART FF F952h FSMSTART FF F752h Flash Memory Start Time Reload Register FMTRAN FF F954h FSMTRAN FF F754h Flash Memory Transition Time Reload Register FMPROG FF F956h FSMPROG FF F756h Flash Memory Programming Time Reload Register FMPERASE FF F958h FSMPERASE FF F758h Flash Memory Page Erase Time Reload Register FMMERASE0 FF F95Ah FSMMERASE0 FF F75Ah Flash Memory Module Erase Time Reload Register 0 FMEND FF F95Eh FSMEND FF F75Eh Flash Memory End Time Reload Register FMMEND FF F960h FSMMEND FF F760h Flash Memory Module Erase End Time Reload Register CP3BT10 rial debug interface. If a majority of the WRPROT bits are set, write access is allowed. Program Memory Data Memory Description FMRCV FF F962h FSMRCV FF F762h Flash Memory Recovery Time Reload Register FMAR0 FF F964h FSMAR0 FF F764h Flash Memory Auto-Read Register 0 FMAR1 FF F966h FSMAR1 FF F766h Flash Memory Auto-Read Register 1 FMAR2 FF F968h FSMAR2 FF F768h Flash Memory Auto-Read Register 2 8.5.1 Flash Memory Information Block Address Register (FMIBAR/FSMIBAR) The FMIBAR register specifies the 8-bit address for read or write access to an information block. Because only word access to the information blocks is supported, the least significant bit (LSB) of the FMIBAR must be 0 (word-aligned). The hardware automatically clears the LSB, without regard to the value written to the bit. The FMIBAR register is cleared after device reset. The CPU bus master has read/write access to this register. 15 8 Reserved IBA 35 7 0 IBA The Information Block Address field holds the word-aligned address of an information block location accessed during a read or write transaction. The LSB of the IBA field is always clear. www.national.com CP3BT10 8.5.2 Flash Memory Information Block Data Register (FMIBDR/FSMIBDR) 8.5.4 The FMIBDR register holds the 16-bit data for read or write access to an information block. The FMIBDR register is cleared after device reset. The CPU bus master has read/ write access to this register. 15 0 Flash Memory 1 Write Enable Register (FM1WER) The FM1WER register controls write protection for the second half of the program flash memory. The data block is divided into 16 8K-byte sections. Each bit in the FM1WER register controls write protection for one of these sections. The FM1WER register is cleared after device reset, so the flash memory is write protected after reset. The CPU bus master has read/write access to this registers. IBD 15 IBD 8.5.3 0 The Information Block Data field holds the data word for access to an information block. For write operations the IBD field holds the data word to be programmed into the informa- FM1WEn tion block location specified by the IBA address. During a read operation from an information block, the IBD field receives the data word read from the location specified by the IBA address. Flash Memory 0 Write Enable Register (FM0WER/FSM0WER) The FM0WER register controls section-level write protection for the first half of the flash program memory. The FMS0WER registers controls section-level write protection for the flash data memory. Each data block is divided into 16 8K-byte sections. Each bit in the FM0WER and FSM0WER registers controls write protection for one of these sections. The FM0WER and FSM0WER registers are cleared after device reset, so the flash memory is write protected after reset. The CPU bus master has read/write access to this registers. 15 0 8.5.5 FM1WE The Flash Memory 1 Write Enable n bits control write protection for a section of a flash memory data block. The address mapping of the register bits is shown below. Bit Logical Address Range 0 02 0000h–02 1FFFh 1–14 ... 15 03 E000h–03 FFFFh Flash Data Memory 0 Write Enable Register (FSM0WER) The FSM0WER register controls write protection for the flash data memory. The data block is divided into 16 512byte sections. Each bit in the FSM0WER register controls write protection for one of these sections. The FSM0WER register is cleared after device reset, so the flash memory is write protected after reset. The CPU bus master has read/ write access to this registers. FM0WE 15 FM0WEn The Flash Memory 0 Write Enable n bits control write protection for a section of a flash memory data block. The address mapping of FSM0WEn the register bits is shown below. Bit Logical Address Range 0 00 0000h–00 1FFFh 1–14 ... 15 01 E000h–01 FFFFh www.national.com 36 0 FSM0WE The Flash Data Memory 0 Write Enable n bits control write protection for a section of a flash memory data block. The address mapping of the register bits is shown below. Bit Logical Address Range 0 0E 0000h–0E 01FFh 1–14 ... 15 0E 1E00h–0E 1FFFh Flash Memory Control Register (FMCTRL/ FSMCTRL) PER The Page Erase Enable bit controls whether a a valid write operation triggers an erase operation on a 1024-byte page of flash memory. Page erase operations are only supported for the main blocks, not the information blocks. A page erase operation on an information block is ignored and does not alter the information block. When the PER bit is set, the PE and MER bits must be clear. This bit must not be changed while the flash program memory is busy being programmed or erased. 0 – Page erase mode disabled. Write operations are performed normally. 1 – A valid write operation to a word location in program memory erases the page that contains the word. The Module Erase Enable bit controls whether a valid write operation triggers an erase operation on an entire block of flash memory. If an information block is written in this mode, both the information block and its corresponding main block are erased. When the MER bit is set, the PE and PER bits must be clear. This bit must not be changed while the flash program memory is busy being programmed or erased. 0 – Module erase mode disabled. Write operations are performed normally. 1 – A valid write operation to a word location in a main block erases the block that contains the word. A valid write operation to a word location in an information block erases the block that contains the word and its associated main block. This register controls the basic functions of the Flash program memory. The register is clear after device reset. The CPU bus master has read/write access to this register. 7 6 5 4 3 2 1 0 MER PER PE IENPROG DISVRF Res. CWD LOWPRW LOWPRW CWD DISVRF IENPROG PE The Low Power Mode controls whether flash program memory is operated in low-power mode, which draws less current when data is read. This is accomplished be only accessing the flash program memory during the first half of the clock period. The low-power mode must not be used at System Clock frequencies above 25 MHz, otherwise a read access may return undefined data. This bit must not be changed while the flash program memory is busy being programmed or erased. 0 – Normal mode. 1 – Low-power mode. The CPU Write Disable bit controls whether the CPU has write access to flash memory. This bit must not be changed while FMBUSY is set. 0 – The CPU has write access to the flash memory 1 – An external debugging tool is the current “owner” of the flash memory interface, so write accesses by the CPU are inhibited. The Disable Verify bit controls the automatic verification feature. This bit must not be changed while the flash program memory is busy being programmed or erased. 0 – New flash program memory contents are automatically verified after programming. 1 – Automatic verification is disabled. The Interrupt Enable for Program bit is clear after reset. The flash program and data memories share a single interrupt channel but have independent interrupt enable control bits. 0 – No interrupt request is asserted to the ICU when the FMFULL bit is cleared. 1 – An interrupt request is made when the FMFULL bit is cleared and new data can be written into the write buffer. The Program Enable bit controls write access of the CPU to the flash program memory. This bit must not be altered while the flash program memory is busy being programmed or erased. The PER and MER bits must be clear when this bit is set. 0 – Programming the flash program memory by the CPU is disabled. 1 – Programming the flash program memory is enabled. MER 8.5.7 Flash Memory Status Register (FMSTAT/ FSMSTAT) This register reports the currents status of the on-chip Flash memory. The FLSR register is clear after device reset. The CPU bus master has read/write access to this register. 7 5 Reserved EERR 37 4 3 2 1 0 DERR FMFULL FMBUSY PERR EERR The Erase Error bit indicates whether an error has occurred during a page erase or module (block) erase. After an erase error occurs, software can clear the EERR bit by writing a 1 to it. Writing a 0 to the EERR bit has no effect. Software must not change this bit while the flash program memory is busy being programmed or erased. 0 – The erase operation was successful. 1 – An erase error occurred. www.national.com CP3BT10 8.5.6 CP3BT10 PERR FMBUSY FMFULL DERR The Program Error bit indicates whether an error has occurred during programming. After a programming error occurs, software can clear the PERR bit by writing a 1 to it. Writing a 0 to the PERR bit has no effect. Software must not change this bit while the flash program memory is busy being programmed or erased. 0 – The programming operation was successful. 1 – A programming error occurred. The Flash Memory Busy bit indicates whether the flash memory (either main block or information block) is busy being programmed or erased. During that time, software must not request any further flash memory operations. If such an attempt is made, the CPU is stopped as long as the FMBUSY bit is active. The CPU must not attempt to read from program memory (including instruction fetches) while it is busy. 0 – Flash memory is ready to receive a new erase or programming request. 1 – Flash memory busy with previous erase or programming operation. The Flash Memory Buffer Full bit indicates whether the write buffer for programming is full or not. When the buffer is full, new erase and write requests may not be made. The IENPROG bit can be enabled to trigger an interrupt when the buffer is ready to receive a new request. 0 – Buffer is ready to receive new erase or write requests. 1 – Buffer is full. No new erase or write requests can be accepted. The Data Loss Error bit indicates that a buffer overrun has occurred during a programming sequence. After a data loss error occurs, software can clear the DERR bit by writing a 1 to it. Writing a 0 to the DERR bit has no effect. Software must not change this bit while the flash program memory is busy being programmed or erased. 0 – No data loss error occurred. 1 – Data loss error occurred. www.national.com 38 8.5.8 Flash Memory Prescaler Register (FMPSR/ FSMPSR) The FMPSR register is a byte-wide read/write register that selects the prescaler divider ratio. The CPU must not modify this register while an erase or programming operation is in progress (FMBUSY is set). At reset, this register is initialized to 04h if the flash memory is idle. The CPU bus master has read/write access to this register. 7 5 4 Reserved FTDIV 8.5.9 0 FTDIV The prescaler divisor scales the frequency of the System Clock by a factor of (FTDIV + 1). Flash Memory Start Time Reload Register (FMSTART/FSMSTART) The FMSTART/FSMSTART register is a byte-wide read/ write register that controls the program/erase start delay time. Software must not modify this register while a program/erase operation is in progress (FMBUSY set). At reset, this register is initialized to 18h if the flash memory is idle. The CPU bus master has read/write access to this register. 7 0 FTSTART FTSTART The Flash Timing Start Delay Count field generates a delay of (FTSTART + 1) prescaler output clocks. Flash Memory Transition Time Reload Register (FMTRAN/FSMTRAN) 8.5.13 The FMTRAN/FMSTRAN register is a byte-wide read/write register that controls some program/erase transition times. Software must not modify this register while program/erase operation is in progress (FMBUSY set). At reset, this register is initialized to 30h if the flash memory is idle. The CPU bus master has read/write access to this register. 7 Flash Memory Module Erase Time Reload Register 0 (FMMERASE0/FSMMERASE0) The FMMERASE0/FSMMERASE0 register is a byte-wide read/write register that controls the module erase pulse width. Software must not modify this register while a program/erase operation is in progress (FMBUSY set). At reset, this register is initialized to EAh if the flash memory is idle. The CPU bus master has read/write access to this register. 0 7 FTTRAN 0 FTMER FTTRAN 8.5.11 The Flash TIming Transition Count field specifies a delay of (FTTRAN + 1) prescaler output clocks. Flash Memory Programming Time Reload Register (FMPROG/FSMPROG) 8.5.14 The FMPROG/FSMPROG register is a byte-wide read/write register that controls the programming pulse width. Software must not modify this register while a program/erase operation is in progress (FMBUSY set). At reset, this register is initialized to 16h if the flash memory is idle. The CPU bus master has read/write access to this register. 7 FTMER 0 The Flash Timing Module Erase Pulse Width field specifies a module erase pulse width of 4096 × (FTMER + 1) prescaler output clocks. Flash Memory End Time Reload Register (FMEND/FSMEND) The FMEND/FSMEND register is a byte-wide read/write register that controls the delay time after a program/erase operation. Software must not modify this register while a program/erase operation is in progress (FMBUSY set). At reset, this register is initialized to 18h when the flash memory on the chip is idle. The CPU bus master has read/write access to this register. FTPROG 7 0 FTEND FTPROG 8.5.12 The Flash Timing Programming Pulse Width field specifies a programming pulse width of 8 × (FTPROG + 1) prescaler output clocks. FTEND The Flash Timing End Delay Count field specifies a delay of (FTEND + 1) prescaler output clocks. Flash Memory Page Erase Time Reload Register (FMPERASE/FSMPERASE) The FMPERASE/FSMPERASE register is a byte-wide read/write register that controls the page erase pulse width. Software must not modify this register while a program/ erase operation is in progress (FMBUSY set). At reset, this register is initialized to 04h if the flash memory is idle. The CPU bus master has read/write access to this register. 7 0 8.5.15 Flash Memory Module Erase End Time Reload Register (FMMEND/FSMMEND) The FMMEND/FSMMEND register is a byte-wide read/write register that controls the delay time after a module erase operation. Software must not modify this register while a program/erase operation is in progress (FMBUSY set). At reset, this register is initialized to 3Ch if the flash memory is idle. The CPU bus master has read/write access to this register. FTPER 7 FTPER 0 FTMEND The Flash Timing Page Erase Pulse Width field specifies a page erase pulse width of 4096 × (FTPER + 1) prescaler output clocks. FTMEND 39 The Flash Timing Module Erase End Delay Count field specifies a delay of 8 × (FTMEND + 1) prescaler output clocks. www.national.com CP3BT10 8.5.10 CP3BT10 8.5.16 8.5.18 Flash Memory Recovery Time Reload Register (FMRCV/FSMRCV) The FMRCV/FSMRCV register is a byte-wide read/write register that controls the recovery delay time between two flash memory accesses. Software must not modify this register while a program/erase operation is in progress (FMBUSY set). At reset, this register is initialized to 04h if the flash memory is idle. The CPU bus master has read/write access to this register. 7 Flash Memory Auto-Read Register 1 (FMAR1/ FSMAR1) The FMAR1 register contains a copy of the Protection Word from Information Block 1. The Protection Word is sampled at reset. The contents of the FMAR1 register define the current Flash memory protection settings. The CPU bus master has read-only access to this register. The FSMAR1 register has the same value as the FMAR1 register. The format is the same as the format of the Protection Word (see Section 8.4.2). 0 15 FTRCV 13 12 10 9 7 6 4 3 1 0 WRPROT RDPROT ISPE EMPTY BOOTAREA 1 FTRCV 8.5.17 The Flash Timing Recovery Delay Count field specifies a delay of (FTRCV + 1) prescaler output clocks. 8.5.19 Flash Memory Auto-Read Register 2 (FMAR2/ FSMAR2) The FMAR2 register is a word-wide read-only register, which is loaded during reset. It is used to build the Code Area start address. At reset, the CPU executes a branch, using the contents of the FMAR2 register as displacement. The CPU bus master has read-only access to this register. Flash Memory Auto-Read Register 0 (FMAR0/ FSMAR0) The FMAR0/FSMAR0 register contains a copy of the Function Word from Information Block 0. The Function Word is sampled at reset. The contents of the FMAR0 register are used to enable or disable special device functions. The CPU The FSMAR2 register has the same value as the FMAR2 bus master has read-only access to this register. The register. FSMAR0 register has the same value as the FMAR0 register 7 0 CADR7:0 15 1 Reserved 0 USB_ENABLE 15 13 CADR15:13 USB_ENABLE The USB_ENABLE bit can be used to force an external USB transceiver into its low-power mode. The USB power mode is dependent on CADR8:0 the USB controller status, the USB_ENABLE bit in the MCFG register (see Section 7.1), and the USB_ENABLE bit in the Function Word. CADR12:9 0 – External USB transceiver forced into lowpower mode. 1 – Transceiver power mode dependent on CADR15:13 USB controller status and programming of the Function Word. www.national.com 40 12 9 CADR12:8 8 CADR8 The Code Area Start Address (bits 8:0) contains the lower 9 bits of the Code Area start address. The CADR8:0 field has a fixed value of 0. The Code Area Start Address (bits 12:9) are loaded during reset with the inverted value of BOOTAREA3:0. The Code Area Start Address (bits 15:13) contains the upper 3 bits of the Code Area start address. The CADR15:13 field has a fixed value of 0. CP3BT10 9.0 DMA Controller The DMA Controller (DMAC) has a register-based programming interface, as opposed to an interface based on I/O control blocks. After loading the registers with source and destination addresses, as well as block size and type of operation, a DMAC channel is ready to respond to DMA transfer requests. A request can only come from on-chip peripherals or software, not external peripherals. On receiving a DMA transfer request, if the channel is enabled, the DMAC performs the following operations: 1. Arbitrates to become master of the CPU bus. 2. Determines priority among the DMAC channels, one clock cycle before T1 of the DMAC transfer cycle. (T1 is the first clock cycle of the bus cycle.) Priority among the DMAC channels is fixed in descending order, with Channel 0 having the highest priority. 3. Executes data transfer bus cycle(s) selected by the values held in the control registers of the channel being serviced, and according to the accessed memory address. The DMAC acknowledges the request during the bus cycle that accesses the requesting device. 4. If the transfer of a block is terminated, the DMAC does the following: Updates the termination bits. Generates an interrupt (if enabled). Goes to step 6. 5. If DMRQn is still active, and the Bus Policy is “continuous”, returns to step 3. 6. Returns mastership of the CPU bus to the CPU. Table 19 DMA Channel Assignment Channel Peripheral Transaction Register 0 (Primary) USB R/W RX/TX FIFO 0 (Secondary) UART R RXBUF 1 (Primary) UART W TXBUF 1 (Secondary) unused N/A N/A 2 (Primary) Audio Interface R ARDR0 2 (Secondary) CVSD/PCM Transcoder R PCMOUT 3 (Primary) Audio Interface W ATDR0 3 (Secondary) CVSD/PCM Transcoder W PCMIN 9.2 TRANSFER TYPES The DMAC uses two data transfer modes, Direct (Flyby) and Indirect (Memory-to-Memory). The choice of mode depends on the required bus performance and whether direct mode is available for the transfer. Indirect mode must be used when the source and destination have differing bus Each DMAC channel can be programmed for direct (flyby) widths, when both the source and destination are in memoor indirect (memory-to-memory) data transfers. Once a ry, and when the destination does not support direct mode. DMAC transfer cycle is in progress, the next transfer request Direct (Flyby) Transfers is sampled when the DMAC acknowledge is de-asserted, 9.2.1 then on the rising edge of every clock cycle. In direct mode each data item is transferred using a single The configuration of either address freeze or address update (increment or decrement) is independent of the number of transferred bytes, transfer direction, or number of bytes in each DMAC transfer cycle. All these can be configured for each channel by programming the appropriate control registers. bus cycle, without reading the data into the DMAC. It provides the fastest transfer rate, but it requires identical source and destination bus widths. The DMAC cannot use Direct cycles between two memory devices. One of the devices must be an I/O device that supports the Direct (Flyby) mechanism, as shown in Figure 2. Each DMAC channel has eight control registers. DMAC channels are described hereafter with the suffix n, where n = 0 to 3, representing the channel number in the registernames. 9.1 Bus State T1 T2 Tidle T1 CLK CHANNEL ASSIGNMENT DMRQ[3:0] Table 19 shows the assignment of the DMA channels to different tasks. Four channels can be shared by a primary and an secondary function. However, only one source at a time can be enabled. If a channel is used for memory block transfers, other resources must be disabled. ADDR ADCA DMACK[3:0] DS005 Figure 2. Direct DMA Cycle Followed by a CPU Cycle Direct mode supports two bus policies: intermittent and continuous. In intermittent mode, the DMAC gives bus mastership back to the CPU after every cycle. In continuous mode, the DMAC remains bus master until the transfer is complet- 41 www.national.com CP3BT10 ed. The maximum bus throughput in intermittent mode is 9.3 OPERATION MODES one transfer for every three System Clock cycles. The maxThe DMAC operates in three different block transfer modes: imum bus throughput in continuous mode is one transfer for single transfer, double buffer, and auto-initialize. every clock cycle. Single Transfer Operation The I/O device which made the DMA request is called the 9.3.1 implied I/O device. The other device can be either memory or another I/O device, and is called the addressed device. This mode provides the simplest way to accomplish a single block data transfer. Because only one address is required in direct mode, this address is taken from the corresponding ADCAn counter. The DMAC channel generates either a read or a write bus cycle, as controlled by the DMACNTLn.DIR bit. Initialization 1. Write the block transfer addresses and byte count into the corresponding ADCAn, ADCBn, and BLTCn counters. 2. Clear the DMACNTLn.OT bit to select non-auto-initialize mode. Clear the DMASTAT.VLD bit by writing a 1 to it. 3. Set the DMACNTLn.CHEN bit to activate the channel and enable it to respond to DMA transfer requests. When the DMACNTLn.DIR bit is clear, a read bus cycle from the addressed device is performed, and the data is written to the implied I/O device. When the DMACNTLn.DIR bit is set, a write bus cycle to the addressed device is performed, and the data is read from the implied I/O device. The configuration of either address freeze or address update (increment or decrement) is independent of the number of transferred bytes, transfer direction, or number of bytes in each DMAC transfer cycle. All these can be configured for each channel by programming the appropriate control register. Termination When the BLTCn counter reaches 0: 1. The transfer operation terminates. 2. The DMASTAT.TC and DMASTAT.OVR bits are set, and the DMASTAT.CHAC bit is cleared. 3. An interrupt is generated if enabled by the DMACNTLn.ETC or DMACNTLn.EOVR bits. Whether 8 or 16 bits are transferred in each cycle is selected by the DMACNTLn.TCS register bit. After the data item has been transferred, the BLTCn counter is decremented by one. The ADCAn counter is updated according to the INCA and ADA fields in the DMACNTLn register. The DMACNTLn.CHEN bit must be cleared before loading the DMACNTLn register to avoid prematurely starting a new DMA transfer. 9.2.2 9.3.2 Indirect (Memory-To-Memory) Transfers Double Buffer Operation In indirect (memory-to-memory) mode, data transfers use This mode allows software to set up the next block transfer two consecutive bus cycles. The data is first read into a tem- while the current block transfer proceeds. porary register, and then written to the destination in the fol- Initialization lowing cycle. This mode is slower than the direct (flyby) 1. Write the block transfer addresses and byte count into mode, but it provides support for different source and destithe ADCAn, ADCBn, and BLTCn counters. nation bus widths. Indirect mode must be used for transfers 2. Clear the DMACNTLn.OT bit to select non-auto-initialbetween memory devices. ize mode. Clear the DMASTAT.VLD bit by writing a 1 to it. If an intermittent bus policy is used, the maximum throughput is one transfer for every five clock cycles. If a continuous 3. Set the DMACNTLn.CHEN bit. This activates the channel and enables it to respond to DMA transfer requests. bus policy is used, maximum throughput is one transfer for 4. While the current block transfer proceeds, write the adevery two clock cycles. dresses and byte count for the next block into the When the DMACNTLn.DIR bit is 0, the first bus cycle reads ADRAn, ADRBn, and BLTRn registers. The BLTRn regdata from the source using the ADCAn counter, while the ister must be written last, because it sets the DMASsecond bus cycle writes the data into the destination using TAT.VLD bit which indicates that all the parameters for the ADCBn counter. When the DMACNTLn.DIR bit is set, the next transfer have been updated. the first bus cycle reads data from the source using the ADCBn counter, while the second bus cycle writes the data into Continuation/Termination the destination addressed by the ADCAn counter. When the BLTCn counter reaches 0: The number of bytes transferred in each cycle is taken from 1. The DMASTAT.TC bit is set. the DMACNTLn.TCS register bit. After the data item has 2. An interrupt is generated if enabled by the been transferred, the BLTCn counter is decremented by DMACNTLn.ETC bit. one. The ADCAn and ADCBn counters are updated accord3. The DMAC channel checks the value of the VLD bit. ing to the INCA, INCB, ADA, and ADB fields in the If the DMASTAT.VLD bit is set: DMACNTLn register. 1. The channel copies the ADRAn, ADRBn, and BLTRn values into the ADCAn, ADCBn, and BLTCn registers. 2. The DMASTAT.VLD bit is cleared. 3. The next block transfer is started. www.national.com 42 1. 2. 3. 4. The transfer operation terminates. The channel sets the DMASTAT.OVR bit. The DMASTAT.CHAC bit is cleared. An interrupt is generated if enabled DMACNTLn.EOVR bit. by the The DMACNTLn.CHEN bit must be cleared before loading the DMACNTLn register to avoid prematurely starting a new DMA transfer. For each channel, use the software DMA transfer request only when the corresponding hardware DMA request is inactive and no terminal count interrupt is pending. Software can poll the DMASTAT.CHAC bit to determine whether the DMA channel is already active. After verifying the DMASTATn.CHAC bit is clear (channel inactive), check the DMASTATn.TC (terminal count) bit. If the TC bit is clear, then no terminal count condition exists and therefore no terminal count interrupt is pending. If the channel is not active and no terminal count interrupt is pending, software may request a DMA transfer. Note: The ADCBn and ADRBn registers are used only in indirect (memory-to-memory) transfer. In direct (flyby) 9.5 DEBUG MODE mode, the DMAC does not use them and therefore does not When the FREEZE signal is active, all DMA operations are copy ADRBn into ADCBn. stopped. They will start again when the FREEZE signal 9.3.3 Auto-Initialize Operation goes inactive. This allows breakpoints to be used in debug This mode allows the DMAC to continuously fill the same systems. memory area without software intervention. 9.6 DMA CONTROLLER REGISTER SET Initialization There are four identical sets of DMA controller registers, as 1. Write the block addresses and byte count into the ADlisted in Table 20. CAn, ADCBn, and BLTCn counters, as well as the Table 20 DMA Controller Registers ADRAn, ADRBn, and BLTRn registers. 2. Set the DMACNTLn.OT bit to select auto-initialize Name Address Description mode. 3. Set the DMACNTLn.CHEN bit to activate the channel Device A Address and enable it to respond to DMA transfer requests. ADCA0 FF F800h Counter Register Continuation Device A Address ADRA0 FF F804h When the BLTCn counter reaches 0: Register 1. The contents of the ADRAn, ADRBn, and BLTRn regisDevice B Address ters are copied to the ADCAn, ADCBn, and BLTCn ADCB0 FF F808h Counter Register counters. 2. The DMAC channel checks the value of the DMASDevice B Address ADRB0 FF F80Ch TAT.TC bit. Register If the DMASTAT.TC bit is set: Block Length BLTC0 FF F810h 1. The DMASTAT.OVR bit is set. Counter Register 2. A level interrupt is generated if enabled by the BLTR0 FF F814h Block Length Register DMACNTLn.EOVR bit. 3. The operation is repeated. DMACNTL0 FF F81Ch DMA Control Register If the DMASTAT.TC bit is clear: DMASTAT0 FF F81Eh DMA Status Register 1. The DMASTAT.TC bit is set. 2. A level interrupt is generated if enabled by the Device A Address ADCA1 FF F820h DMACNTLn.ETC bit. Counter Register 3. The DMAC operation is repeated. Device A Address ADRA1 FF F824h Termination Register The DMA transfer is terminated when the Device B Address ADCB1 FF F828h DMACNTLn.CHEN bit is cleared. Counter Register 9.4 SOFTWARE DMA REQUEST In addition to the hardware requests from I/O devices, a DMA transfer request can also be initiated by software. A software DMA transfer request must be used for block copying between memory devices. ADRB1 FF F82Ch Device B Address Register BLTC1 FF F830h Block Length Counter Register When the DMACNTLn.SWRQ bit is set, the corresponding DMA channel receives a DMA transfer request. When the DMACNTLn.SWRQ bit is clear, the software DMA transfer request of the corresponding channel is inactive. BLTR1 FF F834h Block Length Register DMACNTL1 FF F83Ch DMA Control Register DMASTAT1 FF F83Eh DMA Status Register 43 www.national.com CP3BT10 If the DMASTAT.VLD bit is clear: CP3BT10 9.6.2 Table 20 DMA Controller Registers Name Address Description ADCA2 FF F840h Device A Address Counter Register ADRA2 FF F844h Device A Address Register ADCB2 FF F848h Device B Address Counter Register ADRB2 FF F84Ch Device B Address Register Device A Address Register (ADRAn) The Device A Address register is a 32-bit, read/write register. It holds the 24-bit starting address of either the next source data block, or the next destination data area, according to the DIR bit in the DMACNTLn register. The upper 8 bits of the ADRAn register are reserved and always clear. 31 24 9.6.3 Device B Address Counter Register (ADCBn) FF F850h Block Length Counter Register BLTR2 FF F854h Block Length Register DMACNTL2 FF F85Ch DMA Control Register DMASTAT2 FF F85Eh DMA Status Register ADCA3 FF F860h Device A Address Counter Register ADRA3 FF F864h Device A Address Register ADCB3 FF F868h Device B Address Counter Register ADRB3 FF F86Ch Device B Address Register BLTC3 FF F870h Block Length Counter Register BLTR3 FF F874h Block Length Register DMACNTL3 FF F87Ch DMA Control Register 31 DMASTAT3 FF F87Eh DMA Status Register Reserved 31 24 23 Reserved 9.6.4 0 Device B Address Counter Device B Address Register (ADRBn) The Device B Address register is a 32-bit, read/write register. It holds the 24-bit starting address of either the next source data block or the next destination data area, according to the DIR bit in the CNTLn register. In direct (flyby) mode, this register is not used. The upper 8 bits of the ADCRBn register are reserved and always clear. 24 23 0 Device B Address Device A Address Counter Register (ADCAn) The Device A Address Counter register is a 32-bit, read/ write register. It holds the current 24-bit address of either the source data item or the destination location, depending on the state of the DIR bit in the CNTLn register. The ADA bit of DMACNTLn register controls whether to adjust the pointer in the ADCAn register by the step size specified in the INCA field of DMACNTLn register. The upper 8 bits of the ADCAn register are reserved and always clear. 31 0 Device A Address The Device B Address Counter register is a 32-bit, read/ write register. It holds the current 24-bit address of either the source data item, or the destination location, according to the DIR bit in the CNTLn register. The ADCBn register is updated after each transfer cycle by INCB field of the DMACNTLn register according to ADB bit of the DMACNTLn register. In direct (flyby) mode, this register is not used. The upper 8 bits of the ADCBn register are reserved and always clear. BLTC2 9.6.1 23 Reserved 24 Reserved 23 9.6.5 Block Length Counter Register (BLTCn) The Block Length Counter register is a 16-bit, read/write register. It holds the current number of DMA transfers to be executed in the current block. BLTCn is decremented by one after each transfer cycle. A DMA transfer may consist of 1 or 2 bytes, as selected by the DMACNTLn.TCS bit. 15 0 Block Length Counter 0 Device A Address Counter Note: 0000h is interpreted as 216-1 transfer cycles. www.national.com 44 Block Length Register (BLTRn) DIR The Block Length register is a 16-bit, read/write register. It holds the number of DMA transfers to be performed for the next block. Writing this register automatically sets the DMASTAT.VLD bit. 15 0 OT Block Length Note: 0000h is interpreted as 216-1 transfer cycles. 9.6.7 DMA Control Register (DMACNTLn) BPC The DMA Control register n is a word-wide, read/write register that controls the operation of DMA channel n. This register is cleared at reset. Reserved bits must be written with 0. 7 6 5 4 BPC OT DIR IND TCS EOVR ETC CHEN 15 14 13 12 11 Res. CHEN ETC EOVR TCS IND INCB ADB 3 2 10 INCA 1 9 0 8 ADA SWRQ SWRQ The Channel Enable bit must be set to enable any DMA operation on this channel. Writing a 1 to this bit starts a new DMA transfer even if it is currently a 1. If all DMACNTLn.CHEN bits are clear, the DMA clock is disabled to reduce power. 0 – Channel disabled. 1 – Channel enabled. If the Enable Interrupt on Terminal Count bit is set, it enables an interrupt when the DMASTAT.TC bit is set. 0 – Interrupt disabled. 1 – Interrupt enabled. If the Enable Interrupt on OVR bit is set, it enables an interrupt when the DMASTAT.OVR bit is set. 0 – Interrupt disabled. 1 – Interrupt enabled. The Transfer Cycle Size bit specifies the number of bytes transferred in each DMA transfer cycle. In direct (fly-by) mode, undefined results occur if the TCS bit is not equal to the addressed memory bus width. 0 – Byte transfers (8 bits per cycle). 1 – Word transfers (16 bits per cycle). The Direct/Indirect Transfer bit specifies the transfer type. 0 – Direct transfer (flyby). 1 – Indirect transfer (memory-to-memory). ADA INCA ADB INCB 45 The Transfer Direction bit specifies the direction of the transfer relative to Device A. 0 – Device A (pointed to by the ADCAn register) is the source. In Fly-By mode a read transaction is initialized. 1 – Device A (pointed to by the ADCAn register) is the destination. In Fly-By mode a write transaction is initialized. The Operation Type bit specifies the operation mode of the DMA controller. 0 – Single-buffer mode or double-buffer mode enabled. 1 – Auto-Initialize mode enabled. The Bus Policy Control bit specifies the bus policy applied by the DMA controller. The operation mode can be either intermittent (cycle stealing) or continuous (burst). 0 – Intermittent operation. The DMAC channel relinquishes the bus after each transaction, even if the request is still asserted. 1 – Continuous operation. The DMAC channel n uses the bus continuously as long as the request is asserted. This mode can only be used for software DMA requests. For hardware DMA requests, the BPC bit must be clear. The Software DMA Request bit is written with a 1 to initiate a software DMA request. Writing a 0 to this bit deactivates the software DMA request. The SWRQ bit must only be written when the DMRQ signal for this channel is inactive (DMASTAT.CHAC = 0). 0 – Software DMA request is inactive. 1 – Software DMA request is active. If the Device A Address Control bit is set, it enables updating the Device A address. 0 – ADCAn address unchanged. 1 – ADCAn address incremented or decremented, according to INCA field of DMACNTLn register. The Increment/Decrement ADCAn field specifies the step size for the Device A address increment/decrement. 00 – Increment ADCAn register by 1. 01 – Increment ADCAn register by 2. 10 – Decrement ADCAn register by 1. 11 – Decrement ADCAn register by 2. If the Device B Address Control bit is set, it enables updating the Device B Address. 0 – ADCBn address unchanged. 1 – ADCBn address incremented or decremented, according to INCB field of DMACNTLn register. The Increment/Decrement ADCBn field specifies the step size for the Device B address increment/decrement. 00 – Increment ADCBn register by 1. 01 – Increment ADCBn register by 2. 10 – Decrement ADCBn register by 1. 11 – Decrement ADCBn register by 2. www.national.com CP3BT10 9.6.6 CP3BT10 9.6.8 DMA Status Register (DMASTAT) The DMA status register is a byte-wide, read register that holds the status information for the DMA channel n. This register is cleared at reset. The reserved bits always return zero when read. The VLD, OVR and TC bits are sticky (once set by the occurrence of the specific condition, they remain set until explicitly cleared by software). These bits can be individually cleared by writing 1 to the bit positions in the DMASTAT register to be cleared. Writing 0 to these bits has no effect 7 4 Reserved TC OVR CHAC VLD 3 2 1 VLD CHAC OVR 0 TC The Terminal Count bit indicates whether the transfer was completed by a terminal count condition (BLTCn Register reached 0). 0 – Terminal count condition did not occur. 1 – Terminal count condition occurred. The behavior of the Channel Overrun bit depends on the operation mode (single buffer, double buffer, or auto-initialize) of the DMA channel. In double-buffered mode (DMACNTLn.OT = 0): The OVR bit is set when the present transfer is completed (BLTCn = 0), but the parameters for the next transfer (address and block length) are not valid (DMASTAT.VLD = 0). In auto-initialize mode (DMACNTLn.OT = 1): The OVR bit is set when the present transfer is completed (BLTCn = 0), and the DMASTAT.TC bit is still set. In single-buffer mode: Operates in the same way as double-buffer mode. In single-buffered mode, the DMASTAT.VLD bit should always be clear, so it will also be set when the DMASTAT.TC bit is set. Therefore, the OVR bit can be ignored in this mode. The Channel Active bit continuously indicates the active or inactive status of the channel, and therefore, it is read only. Data written to the CHAC bit is ignored. 0 – Channel inactive. 1 – Indicates that the channel is active (CHEN bit in the CNTLn register is 1 and BLTCn > 0) The Transfer Parameters Valid bit specifies whether the transfer parameters for the next block to be transferred are valid. Writing the BLTRn register automatically sets this bit. The bit is cleared in the following cases: The present transfer is completed and the ADRAn, ADRBn (indirect mode only), and BLTR registers are copied to the ADCAn, ADCBn (indirect mode only), and BLTCn registers. Writing 1 to the VLD bit. www.national.com 46 The Interrupt Control Unit (ICU) receives interrupt requests from internal and external sources and generates interrupts to the CPU. Interrupts from the timers, UARTs, Microwire/ SPI interface, and Multi-Input Wake-Up are all maskable interrupts. The highest-priority interrupt is the Non-Maskable Interrupt (NMI), which is triggered by a falling edge received on the NMI input pin. The priorities of the maskable interrupts are hardwired and therefore fixed. The interrupts are named IRQ0 through IRQ31, in which IRQ0 has the lowest priority and IRQ31 has the highest priority. 10.1 NON-MASKABLE INTERRUPTS The Interrupt Control Unit (ICU) receives the external NMI input and generates the NMI signal driven to the CPU. The NMI input is an asynchronous input with Schmitt trigger characteristics and an internal synchronization circuit, therefore no external synchronizing circuit is needed. The NMI pin triggers an exception on its falling edge. 10.1.1 knowledge bus cycle on receiving a maskable interrupt request from the ICU. During the interrupt acknowledge cycle, a byte is read from address FF FE00h (IVCT register). The byte is used as an index into the Dispatch Table to determine the address of the interrupt handler. Because IRQ0 is not connected to any interrupt source, it would seem that the interrupt vector would never return the value 10h. If it does return a value of 10h, the entry in the dispatch table should point to a default interrupt handler that handles this error condition. One possible condition for this to occur is deassertion of the interrupt before the interrupt acknowledge cycle. 10.3 Table 21 lists the ICU registers. Table 21 Interrupt Controller Registers Non-Maskable Interrupt Processing Name Address Description NMISTAT FF FE02h Non-Maskable Interrupt Status Register EXNMI FF FE04h External NMI Trap Control and Status Register IVCT FF FE00h Interrupt Vector Register IENAM0 FF FE0Eh Interrupt Enable and Mask Register 0 IENAM1 FF FE10h Interrupt Enable and Mask Register 1 ISTAT0 FF FE0Ah Interrupt Status Register 0 ISTAT1 FF FE0Ch Interrupt Status Register 1 The CPU performs an interrupt acknowledge bus cycle when beginning to process a non-maskable interrupt. The address associated with this core bus cycle is within the internal core address space and may be monitored as a Core Bus Monitoring (CBM) clock cycle. At reset, NMI interrupts are disabled and must remain disabled until software initializes the interrupt table, interrupt base register (INTBASE), and the interrupt mode. The external NMI interrupt is enabled by setting the EXNMI.ENLCK bit and will remain enabled until a reset occurs. Alternatively, the external NMI interrupt can be enabled by setting the EXNMI.EN bit and will remain enabled until an interrupt event or a reset occurs. 10.2 INTERRUPT CONTROLLER REGISTERS MASKABLE INTERRUPTS The ICU receives level-triggered interrupt request signals from 31 internal sources and generates a vectored interrupt to the CPU when required. Priority among the interrupt sources (named IRQ1 through IRQ31) is fixed. The maskable interrupts are globally enabled and disabled by the E bit in the PSR register. The EI and DI instructions are used to set (enable) and clear (disable) this bit. The global maskable interrupt enable bit (I bit in the PSR) must also be set before any maskable interrupts are taken. Each interrupt source can be individually enabled or disabled under software control through the ICU interrupt enable registers and also through interrupt enable bits in the peripherals that request the interrupts. The CR16C core supports IRQ0, but in the CP3BT10 it is not connected to any interrupt source. 10.3.1 Non-Maskable Interrupt Status Register (NMISTAT) The NMISTAT register is a byte-wide read-only register. It holds the status of the current pending Non-Maskable Interrupt (NMI) requests. On the CP3BT10, the external NMI input is the only source of NMI interrupts. The NMISTAT register is cleared on reset and each time its contents are read. 7 Maskable Interrupt Processing Interrupt vector numbers are always positive, in the range EXT 10h to 2Fh. The IVCT register contains the interrupt vector of the enabled and pending interrupt with the highest priority. The interrupt vector 10h corresponds to IRQ0 and the lowest priority, while the vector 2Fh corresponds to IRQ31 and the highest priority. The CPU performs an interrupt ac- 1 Reserved 0 EXT 10.2.1 47 The External NMI request bit indicates whether an external non-maskable interrupt request has occurred. Refer to the description of the EXNMI register below for additional details. 0 – No external NMI request. 1 – External NMI request has occurred. www.national.com CP3BT10 10.0 Interrupts CP3BT10 10.3.2 10.3.3 External NMI Trap Control and Status Register (EXNMI) The EXNMI register is a byte-wide read/write register. It indicates the current value of the NMI pin and controls the NMI interrupt trap generation based on a falling edge of the NMI pin. TST, EN and ENLCK are cleared on reset. When writing to this register, all reserved bits must be written with 0 for the device to function properly 7 3 Reserved EN PIN ENLCK The IVCT register is a byte-wide read-only register which reports the encoded value of the highest priority maskable interrupt that is both asserted and enabled. The valid range is from 10h to 2Fh. The register is read by the CPU during an interrupt acknowledge bus cycle, and INTVECT is valid during that time. It may contain invalid data while INTVECT is updated. 2 1 0 7 6 ENLCK PIN EN 0 0 The EXNMI trap enable bit is one of two bits that can be used to enable NMI interrupts. The bit is cleared by hardware at reset and whenever the NMI interrupt occurs (EXNMI.EXT set). It is intended for applications where the NMI input toggles frequently but nested NMI traps are not desired. For these applications, the EN bit needs to be re-enabled before exiting the trap handler. When used this way, the ENLCK bit should never be set. The EN bit can be set and cleared by software (software can set this bit only if EXNMI.EXT is cleared), and should only be set after the interrupt base register and the interrupt stack pointer have been set up. 0 – NMI interrupts not enabled by this bit (but may be enabled by the ENLCK bit). 1 – NMI interrupts enabled. The PIN bit indicates the state (non-inverted) on the NMI input pin. This bit is read-only, data written into it is ignored. 0 – NMI pin not asserted. 1 – NMI pin asserted. The EXNMI trap enable lock bit is used to permanently enable NMI interrupts. Only a device reset can clear the ENLCK bit. This allows the external NMI feature to be enabled after the interrupt base register and the interrupt stack pointer have been set up. When the ENLCK bit is set, the EN bit is ignored. 0 – NMI interrupts not enabled by this bit (but may be enabled by the EN bit). 1 – NMI interrupts enabled. INTVECT 10.3.4 48 5 0 INTVECT The Interrupt Vector field indicates the highest priority interrupt which is both asserted and enabled. Interrupt Enable and Mask Register 0 (IENAM0) The IENAM0 register is a word-wide read/write register which holds bits that individually enable and disable the maskable interrupt sources IRQ1 through IRQ15. The register is initialized to FFFFh upon reset. 15 1 IENA IENA 10.3.5 0 Res. Each Interrupt Enable bit enables or disables the corresponding interrupt request IRQ1 through IRQ15, for example IENA15 controls IRQ15. Because IRQ0 is not used, IENA0 is ignored. 0 – Interrupt is disabled. 1 – Interrupt is enabled. Interrupt Enable and Mask Register 1 (IENAM1) The IENAM1 register is a word-wide read/write register which holds bits that individually enable and disable the maskable interrupt sources IRQ16 through IRQ31. The register is initialized to FFFFh at reset. 15 0 IENA IENA www.national.com Interrupt Vector Register (IVCT) Each Interrupt Enable bit enables or disables the corresponding interrupt request IRQ16 through IRQ31, for example IENA15 controls IRQ31. 0 – Interrupt is disabled. 1 – Interrupt is enabled. 10.4 Interrupt Status Register 0 (ISTAT0) MASKABLE INTERRUPT SOURCES The ISTAT0 register is a word-wide read-only register. It in- Table 22 shows the interrupts assigned to various on-chip dicates which maskable interrupt inputs to the ICU are ac- maskable interrupts. The priority of simultaneous maskable tive. These bits are not affected by the state of the interrupts is linear, with IRQ31 having the highest priority. corresponding IENA bits. Table 22 Maskable Interrupts Assignment 15 1 IST IST 10.3.7 IRQ Number 0 Res. The Interrupt Status bits indicate if a maskable interrupt source is signalling an interrupt request. IST[15:1] correspond to IRQ15 to IRQ1 respectively. Because the IRQ0 interrupt is not used, bit 0 always reads back 0. 0 – Interrupt is not active. 1 – Interrupt is active. Interrupt Status Register 1 (ISTAT1) The ISTAT1 register is a word-wide read-only register. It indicates which maskable interrupt inputs into the ICU are active. These bits are not affected by the state of the corresponding IENA bits. 15 0 IST IST The Interrupt Status bits indicate if a maskable interrupt source is signalling an interrupt request. IST[31:16] correspond to IRQ31 to IRQ16, respectively. 0 – Interrupt is not active. 1 – Interrupt is active. 49 Details IRQ31 TWM (Timer 0) IRQ30 Bluetooth LLC 0 IRQ29 Bluetooth LLC 1 IRQ28 Bluetooth LLC 2 IRQ27 Bluetooth LLC 3 IRQ26 Bluetooth LLC 4 IRQ25 Bluetooth LLC 5 IRQ24 USB Interface IRQ23 DMA Channel 0 IRQ22 DMA Channel 1 IRQ21 DMA Channel 2 IRQ20 DMA Channel 3 IRQ19 Reserved IRQ18 Advanced Audio Interface IRQ17 UART Rx IRQ16 CVSD/PCM Converter IRQ15 ACCESS.bus Interface IRQ14 TA (Timer input A) IRQ13 TB (Timer input B) IRQ12 VTUA (VTU Interrupt Request 1) IRQ11 VTUB (VTU Interrupt Request 2) IRQ10 VTUC (VTU Interrupt Request 3) IRQ9 VTUD (VTU Interrupt Request 4) IRQ8 Microwire/SPI Rx/Tx IRQ7 UART Tx IRQ6 UART CTS IRQ5 MIWU Interrupt 0 IRQ4 MIWU Interrupt 1 IRQ3 MIWU Interrupt 2 IRQ2 MIWU Interrupt 3 IRQ1 Flash Program/Data Memory IRQ0 Reserved www.national.com CP3BT10 10.3.6 CP3BT10 All reserved or unused interrupt vectors should point to a default or error interrupt handlers. 10.5 NESTED INTERRUPTS Nested NMI interrupts are always enabled. Nested maskable interrupts are disabled by default, however an interrupt handler can allow nested maskable interrupts by setting the I bit in the PSR. The LPR instruction is used to set the I bit. Nesting of specific maskable interrupts can be allowed by disabling interrupts from sources for which nesting is not allowed, before setting the I bit. Individual maskable interrupt sources can be disabled using the IENAM0 and IENAM1 registers. Any number of levels of nested interrupts are allowed, limited only by the available memory for the interrupt stack. www.national.com 50 The Triple Clock and Reset module generates a 12 MHz Main Clock and a 32.768 kHz Slow Clock from external crystal networks or external clock sources. It provides various clock signals for the rest of the chip. It also provides the main system reset signal, a power-on reset function, Main Clock prescalers to generate two additional low-speed clocks, and a 32-kHz oscillator start-up delay. Figure 3 is block diagram of the Triple Clock and Reset module. TWM (Invalid Watchdog Service) Device Reset Flash Interface (Program/Erase Busy) Reset Module External Reset Stretched Reset Reset Power-On-Reset Module (POR) Stop Main Osc. Stop Main Osc Preset X1CKI Start-Up-Delay 14-Bit Timer High Frequency Oscillator Main Clock Div. by 2 4-Bit Aux1 Prescaler Auxiliary Clock 1 4-Bit Aux2 Prescaler Auxiliary Clock 2 8-Bit Prescaler Slow Clock Prescaler X2CKI Mux X1CKO Good Main Clock Low Frequency Oscillator Slow Clock Slow Clock Select Start-Up-Delay 8-Bit Timer Time-out Good Slow Clock Preset X2CKO Stop Slow Osc Bypass 32 kHz Osc Mux Fast Clock Prescaler 4-Bit Prescaler System Clock Mux Fast Clock Select PLL Clock PLL (x3, x4, or x5) Bypass PLL Good PLL Clock Stop PLL Stop PLL DS006 Figure 3. Triple Clock and Reset Module 51 www.national.com CP3BT10 11.0 Triple Clock and Reset CP3BT10 11.1 EXTERNAL CRYSTAL NETWORK An external crystal network is connected to the X1CKI and X1CKO pins to generate the Main Clock, unless an external clock signal is driven on the X1CKI pin. A similar external crystal network may be used at pins X2CKI and X2CKO for the Slow Clock. If an external crystal network is not used for the Slow Clock, the Slow Clock is generated by dividing the fast Main Clock. The crystal network you choose may require external components different from the ones specified in this datasheet. In this case, consult with National’s engineers for the component specifications crystal network and Table 24 shows the component specifications for the 32.768 kHz crystal network. X1CKI/X2CKI C1 12 MHz/32.768 kHz Crystal X1CKO/X2CKO The crystals and other oscillator components must be placed close to the X1CKI/X1CKO and X2CKI/X2CKO device input pins to keep the printed trace lengths to an absolute minimum. C2 Figure 4 shows the required crystal network at X1CKI/ X1CKO and optional crystal network at X2CKI/X2CKO. Table 23 shows the component specifications for the main GND DS007 Figure 4. External Crystal Network Table 23 Component Values of the High Frequency Crystal Circuit Component Crystal Parameters Resonance Frequency Type Max. Serial Resistance Max. Shunt Capacitance Load Capacitance Capacitor C1, C2 Capacitance Values Tolerance 12 MHz ± 20 ppm AT-Cut 50 Ω 7 pF 22 pF N/A 22 pF 20% Table 24 Component Values of the Low Frequency Crystal Circuit Component Crystal Parameters Resonance Frequency Type Maximum Serial Resistance Maximum Shunt Capacitance Load Capacitance Min. Q factor Capacitor C1, C2 Tolerance 32.768 kHz Parallel N-Cut or XY-bar 40 kΩ 2 pF 12.5 pF 40000 N/A 25 pF 20% Capacitance Choose capacitor component values in the tables to obtain the specified load capacitance for the crystal when combined with the parasitic capacitance of the trace, socket, and package (which can vary from 0 to 8 pF). As a guideline, the load capacitance is: C1 × C2- + Cparasitic CL = -------------------C1 + C2 C2 > C1 C1 can be trimmed to obtain the desired load capacitance. The start-up time of the 32.768 kHz oscillator can vary from one to six seconds. The long start-up time is due to the high www.national.com Values 52 Q value and high serial resistance of the crystal necessary to minimize power consumption in Power Save mode. 11.2 MAIN CLOCK The Main Clock is generated by the 12-MHz high-frequency oscillator or driven by an external signal (typically the LMX5252 RF chip). It can be stopped by the Power Management Module to reduce power consumption during periods of reduced activity. When the Main Clock is restarted, a 14-bit timer generates a Good Main Clock signal after a start-up delay of 32,768 clock cycles. This signal is an indicator that the high-frequency oscillator is stable. The PRSFC register must not be modified while the System Clock is derived from the PLL Clock. The System Clock must be derived from the low-frequency oscillator clock while the MODE field is modified. When the timer reaches zero, it stops counting and asserts the Good Slow Clock signal, which indicates that the Slow Clock is stable. 11.7 11.5 SYSTEM CLOCK The System Clock drives most of the on-chip modules, including the CPU. Typically, it is driven by the Main Clock, but it can also be driven by the PLL. In either case, the clock sig11.3 SLOW CLOCK nal is passed through a programmable divider (scale factors The Slow Clock is necessary for operating the device in re- from ÷1 to ÷16). duced power modes and to provide a clock source for mod11.6 AUXILIARY CLOCKS ules such as the Timing and Watchdog Module. The Slow Clock operates in a manner similar to the Main Auxiliary Clock 1 and Auxiliary Clock 2 are generated from Clock. The Stop Slow Osc signal from the Power Manage- Main Clock for use by certain peripherals. Auxiliary Clock 1 ment Module stops and starts the low-frequency (32.768 is available for the Bluetooth controller and the Advanced kHz) oscillator. When this signal is asserted, it presets a 6- Audio Interface. Auxiliary Clock 2 is available for the CVSD/ bit timer to 3Fh and disables the low-frequency oscillator. PCM transcoder. The Auxiliary clocks may be configured to When the signal goes inactive, the low-frequency oscillator keep these peripherals running when the System Clock is starts, and the 6-bit timer counts down from its preset value. slowed down or suspended during low-power modes. For systems that do not require a reduced power consumption mode, the external crystal network may be omitted for the Slow Clock. In that case, the Slow Clock can be synthesized by dividing the Main Clock by a prescaler factor. The prescaler circuit consists of a fixed divide-by-2 counter and a programmable 8-bit prescaler register. This allows a choice of clock divisors ranging from 2 to 512. The resulting Slow Clock frequency must not exceed 100 kHz. The CP3BT10 has specific Power On Reset (POR) timing requirements that must be met to prevent corruption of the on-chip flash program and data memories. This timing sequence shown in Figure 5. All reset circuits must ensure that this timing sequence is always maintained during power-up and power-down. The design of the power supply also affects how this sequence is implemented. The power-up sequence is: 1. The RESET pin must be held low until both IOVCC and VCC have reached the minimum levels specified in the DC Characteristics section. IOVCC and VCC are allowed to reach their nominal levels at the same time which is the best-case scenario. 2. After both of these supply voltage rails have met this condition, then the RESET pin may be driven high. At power-up an internal 14-bit counter is set to 3FFFh and begins counting down to 0 after the crystal oscillator becomes stable. When this counter reaches 0, the onchip RESET signal is driven high unless the external RESET pin is still being held low. This prevents the CP3BT10 from coming out of reset with an unstable clock source. A software-programmable multiplexer selects either the prescaled Main Clock or the 32.768 kHz oscillator as the Slow Clock. At reset, the prescaled Main Clock is selected, ensuring that the Slow Clock is always present initially. Selection of the 32.768 kHz oscillator as the Slow Clock disables the clock prescaler, which allows the CLK1 oscillator to be turned off, which reduces power consumption and radiated emissions. This can be done only if the module detects a toggling low-speed oscillator. If the low-speed oscillator is not operating, the prescaler remains available as the Slow Clock source. 11.4 PLL CLOCK The PLL Clock is generated by the PLL from the 12 MHz Main Clock by applying a multiplication factor of ×3, ×4, or ×5. The USB interface is clocked directly by the PLL Clock and requires a 48 MHz clock, so a ×4 scaling factor must be used if the USB interface is active. The power-down sequence is: 1. The RESET pin must be driven low as soon as either the IOVCC or VCC voltage rail reaches the minimum levels specified in the DC Characteristics. 2. The RESET pin must then be held low until the Main Clock is stopped. The Main Clock will decay with the same profile as IOVCC. To enable the PLL: 1. Set the PLL multiplication factor in PRFSC.MODE. 2. Clear the PLL power-down bit CRCTRL.PLLPWD. 3. Clear the high-frequency clock select bit CRCTRL.FCLK. 4. Read CRCTRL.FCLK, and go back to step 3 if not clear. The CRCTRL.FCLK bit will be clear only after the PLL has stabilized, so software must repeat step 3 until the bit is clear. The clock source can be switched back to the Main Clock by setting the CRCTRL.FCLK bit. POWER-ON RESET Meeting the power-down reset conditions ensures that software will not be executed at voltage levels that may cause incorrect program execution or corruption of the flash memories. This situation must be avoided because the Main Clock decays with the IOVCC supply rather than stopping immediately when IOVCC falls below the minimum specified level. 53 www.national.com CP3BT10 The Stop Main Osc signal from the Power Management Module stops and starts the high-frequency oscillator. When this signal is asserted, it presets the 14-bit timer to 3FFFh and stops the high-frequency oscillator. When the signal goes inactive, the high-frequency oscillator starts and the 14-bit timer counts down from its preset value. When the timer reaches zero, it stops counting and asserts the Good Main Clock signal. CP3BT10 The external reset circuits presented in the following sections provide varying levels of additional fault tolerance and expandability and are presented as possible examples of solutions to be used with the CP3BT10. It is important to note, however, that any design for the reset circuit and power supply must meet the timing requirements shown in Figure 5. 11.7.2 Manual and SDI External Reset An external reset circuit based on the LM3724 5-Pin Microprocessor Reset Circuit is shown in Figure 7. The LM3724 produces a 190-ms logic low reset pulse when the power supply rises above a threshold voltage or a manual reset button is pressed. Various reset thresholds are available for the LM3724, however the option for 3.08V is most suitable for a CP3BT10 device operating from an IOVCC at 3.3V. 2.25V IOVCC IOVCC IOVCC 2.25V Core VCC 10k Ω LM3724 5-Pin Reset Circuit RESET RESET Manual Reset Main Clock GND Power Up Power Down DS515 Figure 5. 11.7.1 CP3BT1x SDI Reset Power-On Reset Timing Figure 7. Manual and SDI External Reset Simple External Reset A simple external reset circuit with brown-out and glitch protection based on the LM809 3-Pin Microprocessor Reset Circuit is shown in Figure 6. The LM809 produces a 240-ms logic low reset pulse when the power supply rises above a threshold voltage. Various reset thresholds are available for the LM809, however the options for 2.93V and 3.08V are most suitable for a CP3BT10 device operating from an IOVCC at 3.0V to 3.3V. IOVCC IOVCC CP3BT1x LM809 3-Pin Reset Circuit RESET GND DS508 Figure 6. Simple External Reset www.national.com DS509 54 The LM3724 provides a debounced input for a manual pushbutton reset switch. It also has an open-drain output which can be used for implementing a wire-OR connection with a reset signal from a serial debug interface. This circuit is typical of a design to be used in a development or evaluation environment, however it is a good recommendation for all general CP3BT10 designs. If an SDI interface is not implemented, an LM3722 with active pullup may be used. 11.8 Fault-Tolerant External Reset CLOCK AND RESET REGISTERS An external reset circuit based on the LM3710 Microproces- Table 25 lists the clock and reset registers. sor Supervisory Circuit is shown in Figure 8. It provides a Table 25 Clock and Reset Registers high level of fault tolerance in that it provides the ability to monitor both the VCC supply for the core logic and the IOName Address Description VCC supply. It also provides a low-voltage indication for the IOVCC supply and an external watchdog timer. Clock and Reset CRCTRL FF FC40h Control Register Core VCC (2.5V) IOVCC IOVCC PRSFC FF FC42h High Frequency Clock Prescaler Register PRSSC FF FC44h Low Frequency Clock Prescaler Register PRSAC FF FC46h Auxiliary Clock Prescaler Register VCC CP3BT1x 278k Ω Reset Output Power Fail Input (PFI) 332k Ω LM3710 Power Fail Output (PFO) Supervisory Circuit with Low Line Output (LLO) Power-Fail and Low-Line Watchdog Input (WDI) Detection RESET NMI IRQ GPIO 11.8.1 Manual Reset GND DS510 Clock and Reset Control Register (CRCTRL) The CRCTRL register is a byte-wide read/write register that controls the clock selection and contains the power-on reset status bit. At reset, the CRCTRL register is initialized as described below: Figure 8. Fault-Tolerant External Reset 7 6 Reserved The signals shown in Figure 8 are: Core VCC—the 2.5V power supply rail for the core logic. IOVCC—the 2.5–3.3V power supply rail for the I/O logic. SCLK Watchdog Input (WDI)—this signal is asserted by the CP3BT10 at regular intervals to indicate normal operation. A general-purpose I/O (GPIO) port may be used to provide this signal. If the internal watchdog timer in the CP3BT10 is used, then the LM3704 Microprocessor Supervisory Circuit can provide the same features as the FCLK LM3710 but without the watchdog timer. RESET—an active-low reset signal to the CP3BT10. The LM3710 is available in versions with active pullup or an open-drain RESET output. Power-Fail Input (PFI)—this is a voltage level derived from the Core VCC power supply rail through a simple resistor divider network. Power-Fail Output (PFO)—this signal is asserted when the voltage on PFI falls below 1.225V. PFO is connected to the non-maskable interrupt (NMI) input on the CP3BT10. A system shutdown routine can then be invoked by the NMI handler. Low Line Output (LLO)—this signal is asserted when the PLLPWD main IOVCC level fails below a warning threshold voltage but remains above a reset detection threshold. This signal may be routed to the NMI input on the CP3BT10 or to a separate interrupt input. These additional status and feedback mechanisms allow the CP3BT10 to recover from software hangs or perform system shutdown functions before being placed into reset. The standard reset threshold for the LM3710 is 3.08V with other options for different watchdog timeout and reset timeouts. The selection of these values are much more application-specific. The combination of a watchdog timeout period of 1600 ms and a reset period of 200 ms is a reasonable starting point. 55 5 4 3 2 1 0 POR ACE2 ACE1 PLLPWD FCLK SCLK The Slow Clock Select bit controls the clock source used for the Slow Clock. 0 – Slow Clock driven by prescaled Main Clock. 1 – Slow Clock driven by 32.768 kHz oscillator. The Fast Clock Select bit selects between the 12 MHz Main Clock and the PLL as the source used for the System Clock. After reset, the Main Clock is selected. Attempting to switch to the PLL while the PLLPWD bit is set (PLL is turned off) is ignored. Attempting to switch to the PLL also has no effect if the PLL output clock has not stabilized. 0 – The System Clock prescaler is driven by the output of the PLL. 1 – The System Clock prescaler is driven by the 12-MHz Main Clock. This is the default after reset. The PLL Power-Down bit controls whether the PLL is active or powered down (Stop PLL signal asserted). When this bit is set, the on-chip PLL stays powered-down. Otherwise it is powered-up or it can be controlled by the Power Management Module, respectively. Before software can power-down the PLL in Active mode by setting the PLLPWD bit, the FCLK bit must be set. Attempting to set the PLLPWD bit while the FCLK bit is clear is ignored. The FCLK bit cannot be cleared until the PLL clock has stabilized. After reset this bit is set. 0 – PLL is active. 1 – PLL is powered down. www.national.com CP3BT10 11.7.3 CP3BT10 ACE1 When the Auxiliary Clock Enable bit is set and a stable Main Clock is provided, the Auxiliary Clock 1 prescaler is enabled and generates the first Auxiliary Clock. When the ACE1 bit is clear or the Main Clock is not stable, Auxiliary Clock 1 is stopped. Auxiliary Clock 1 is used as the clock input for the Bluetooth LLC and the audio interface. After reset this bit is clear. 0 – Auxiliary Clock 1 is stopped. 1 – Auxiliary Clock 1 is active if the Main Clock is stable. When the Auxiliary Clock Enable 2 bit is set and a stable Main Clock is provided, the Auxiliary Clock 2 prescaler is enabled and generates Auxiliary Clock 2. When the ACE2 bit is clear or the Main Clock is not stable, the Auxiliary Clock 2 is stopped. Auxiliary Clock 2 is used as the clock input for the CVSD/PCM transcoder. After reset this bit is clear. 0 – Auxiliary Clock 2 is stopped. 1 – Auxiliary Clock 2 is active if the Main Clock is stable. Power-On-Reset - The Power-On-Reset bit is set when a power-turn-on condition has been detected. This bit can only be cleared by software, not set. Writing a 1 to this bit will be ignored, and the previous value of the bit will be unchanged. 0 – Software cleared this bit. 1 – Software has not cleared his bit since the last reset. ACE2 POR 11.8.2 High Frequency Clock Prescaler Register (PRSFC) low-frequency oscillator clock while the MODE field is modified. Res FCDIV MODE 6 4 MODE 3 11.8.3 11.8.4 56 Reserved 001 Reserved Reserved 010 Reserved Reserved 011 36 MHz 3× Mode 100 48 MHz 4× Mode 101 60 MHz 5× Mode 110 Reserved Reserved 111 Reserved Reserved Low Frequency Clock Prescaler Register (PRSSC) 0 SCDIV The Slow Clock Divisor field specifies a divisor to be used when generating the Slow Clock from the Main Clock. The Main Clock is divided by a value of (2 × (SCDIV + 1)) to obtain the Slow Clock. At reset, the SCDIV register is initialized to B6h, which generates a Slow Clock rate of 32786.89 Hz. This is about 0.5% faster than a Slow Clock generated from an external 32768 Hz crystal network. Auxiliary Clock Prescaler Register (PRSAC) The PRSAC register is a byte-wide read/write register that holds the clock divisor values for prescalers used to generate the two auxiliary clocks from the Main Clock. The register is initialized to FFh at reset. 7 4 ACDIV2 ACDIV1 ACDIV2 www.national.com Reserved 7 0 The Fast Clock Divisor specifies the divisor used to obtain the high-frequency System Clock from the PLL or Main Clock. The divisor is (FCDIV + 1). The PLL MODE field specifies the operation mode of the on-chip PLL. After reset the MODE bits are initialized to 100b, so the PLL is configured to generate a 48-MHz clock. This register must not be modified when the System Clock is derived from the PLL Clock. The System Clock must be derived from the 000 The PRSSC register is a byte-wide read/write register that holds the clock divisor used to generate the Slow Clock from the Main Clock. The register is initialized to B6h at reset. SCDIV FCDIV Description MODE2:0 The PRSFC register is a byte-wide read/write register that holds the 4-bit clock divisor used to generate the high-frequency clock. In addition, the upper three bits are used to control the operation of the PLL. The register is initialized to 4Fh at reset (except in PROG mode.) 7 Output Frequency (from 12 MHz input clock) 3 0 ACDIV2 The Auxiliary Clock Divisor 1 field specifies the divisor to be used for generating Auxiliary Clock 1 from the Main Clock. The Main Clock is divided by a value of (ACDIV1 + 1). The Auxiliary Clock Divisor 2 field specifies the divisor to be used for generating Auxiliary Clock 2 from the Main Clock. The Main Clock is divided by a value of (ACDIV2 + 1). The Power Management Module (PMM) improves the efficiency of the CP3BT10 by changing the operating mode (and therefore the power consumption) according to the required level of device activity. The device implements four power modes: Active Power Save Idle Halt Table 26 summarizes the differences between power modes: the state of the high-frequency oscillator (on or off), the System Clock source (clock used by most modules), and the clock source used by the Timing and Watchdog Module (TWM). The high-frequency oscillator generates the 12-MHz Main Clock, and the low-frequency oscillator generates a 32.768 kHz clock. The Slow Clock can be driven by the 32.768 kHz clock or a scaled version of the Main Clock. Table 26 Power Mode Operating Summary Mode Active High-Frequency Oscillator On System Clock Main Clock Slow Clock Slow Clock Slow Clock Idle Off None Slow Clock Halt Off None None In Power Save mode, Slow Clock is used as the System Clock which drives the CPU and most on-chip modules. If Slow Clock is driven by the 32.768 kHz oscillator and no onchip module currently requires the 12-MHz Main Clock, software can disable the high-frequency oscillator to further reduce power consumption. Auxiliary Clocks 1 and 2 can be turned off under software control before switching to a reduced power mode, or they may remain active as long as Main Clock is also active. If the system does not require the PLL output clock, the PLL can be disabled. Alternatively, the Main Clock and the PLL can also be controlled by the Hardware Clock Control function, if enabled. The clock architecture is described in Section 11.0. The Bluetooth LLC can either be switched to the 32 kHz clock internally in the module, or it remains running off Auxiliary clock 1 as long as the Main Clock and Auxiliary Clock 1 are enabled. It is recommended to keep CPU activity at a minimum by executing the WAIT instruction to guarantee low power consumption in the system. The low-frequency oscillator continues to operate in all four modes and power must be provided continuously to the device power supply pins. In Halt mode, however, Slow Clock does not toggle, and as a result, the TWM timer and Watchdog Module do not operate. In Power Save mode, the highfrequency oscillator can be turned on or off under software control, as long as the low-frequency oscillator is used to drive Slow Clock. 12.1 POWER SAVE MODE In Power Save mode, some modules are disabled or their operation is restricted. Other modules, including the CPU, continue to function normally, but operate at a reduced clock rate. Details of each module’s activity in Power Save mode are described in each module’s descriptions. TWM Clock Power Save On or Off 12.2 ACTIVE MODE In Active mode, the high-frequency oscillator is active and generates the 12-MHz Main Clock. The 32.768 kHz oscillator is active and may be used to generate the Slow Clock. The PLL can be active or inactive, as required. Most on-chip modules are driven by the System Clock. The System Clock can be the PLL Clock after a programmable divider or the 12-MHz Main Clock. The activity of peripheral modules is controlled by their enable bits. Power consumption can be reduced in this mode by selectively disabling modules and by executing the WAIT instruction. When the WAIT instruction is executed, the CPU stops executing new instructions until it receives an interrupt signal. After reset, the CP3BT10 is in Active Mode. 12.3 IDLE MODE In Idle mode, the System Clock is disabled and therefore the clock is stopped to most modules of the device. The DHC and DMC bits in the PMMCR register must be set before entering this mode to disable the PLL and the high-frequency oscillator. The low-frequency oscillator remains active. The Power Management Module (PMM) and the Timing and Watchdog Module (TWM) continue to operate off the Slow Clock. Idle mode can only be entered from Active mode. 12.4 HALT MODE In Halt mode, all the device clocks, including the System Clock, Main Clock, and Slow Clock, are disabled. The DHC and DMC bits in the PMMCR register must be set before entering this mode. The high-frequency oscillator and PLL are off. The low-frequency oscillator continues to operate, however its circuitry is optimized to guarantee lowest possible power consumption. This mode allows the device to reach the absolute minimum power consumption without losing its state (memory, registers, etc.). Halt mode can only be entered from Active mode. 12.5 HARDWARE CLOCK CONTROL The Hardware Clock Control (HCC) mechanism gives the Bluetooth Lower Link Controller (LLC) individual control over the high-frequency oscillator and the PLL. The Bluetooth LLC can enter a Sleep mode for a specified number of low-frequency clock cycles. While the Bluetooth LLC is in Sleep mode and the CP3BT10 is in Power Savemode, the HCC mechanism may be used to control whether the highfrequency oscillator, PLL, or both units are disabled. 57 www.national.com CP3BT10 12.0 Power Management CP3BT10 Altogether, three mechanisms control whether the high-frequency oscillator is active, and four mechanisms control whether the PLL is active: IDLE HCC Bits: The HCCM and HCCH bits in the PMMCR register may be used to disable the high-frequency oscillator and PLL, respectively, in Power Save mode when the Bluetooth LLC is in Sleep mode. Disable Bits: The DMC and DHC bits in the PMMCR register may be used to disable the high-frequency oscillator and PLL, respectively, in Power Save mode. These bits must be set in Idle and Halt mode. When used to disable the high-frequency oscillator or PLL, the DMC and HALT DHC bits override the HCC mechanism. Power Management Mode: Halt mode disables the high-frequency oscillator and PLL. Active Mode enables them. The DMC and DHC bits and the HCC mechanism have no effect in Active or Halt mode. PLL Power Down Bit: The PLLPWD bit in the CRCTRL register can be used to disable the PLL in all modes. This bit does not affect the high-frequency oscillator. 12.6 POWER MANAGEMENT REGISTERS Table 27 lists the power management registers. Table 27 Power Management Registers Name Address Description PMMCR FF FC60h Power Management Control Register PMMSR FF FC62h Power Management Status Register 12.6.1 WBPSM Power Management Control Register (PMMCR) The Power Management Control/Status Register (PMMCR) is a byte-wide, read/write register that controls the operating power mode (Active, Power Save, Idle, or Halt) and enables or disables the high-frequency oscillator and PLL in the Power Save mode. At reset, the non-reserved bits of this register are cleared. The format of the register is shown below. DMC 7 6 5 4 3 2 1 0 HCCH HCCM DHC DMC WBPSM HALT IDLE PSM PSM If the Power Save Mode bit is clear and the WBPSM bit is clear, writing 1 to the PSM bit causes the device to start the switch to Power Save mode. If the WBPSM bit is set when the PSM bit is written with 1, entry into Power Save mode is delayed until execution of a WAIT instruction. The PSM bit becomes set after the switch to Power Save mode is com- DHC plete. The PSM bit can be cleared by software, and it can be cleared by hardware when a hardware wake-up event is detected. 0 – Device is not in Power Save mode. 1 – Device is in Power Save mode. www.national.com 58 The Idle Mode bit indicates whether the device has entered Idle mode. The WBPSM bit must be set to enter Idle mode. When the IDLE bit is written with 1, the device enters IDLE mode at the execution of the next WAIT instruction. The IDLE bit can be set and cleared by software. It is also cleared by the hardware when a hardware wake-up event is detected. 0 – Device is not in Idle mode. 1 – Device is in Idle mode. The Halt Mode bit indicates whether the device is in Halt mode. Before entering Halt mode, the WBPSM bit must be set. When the HALT bit is written with 1, the device enters the Halt mode at the execution of the next WAIT instruction. When in HALT mode, the PMM stops the System Clock and then turns off the PLL and the high-frequency oscillator. The HALT bit can be set and cleared by software. The Halt mode is exited by a hardware wake-up event. When this signal is set high, the oscillator is started. After the oscillator has stabilized, the HALT bit is cleared by the hardware. 0 – Device is not in Halt mode. 1 – Device is in Halt mode. When the Wait Before Power Save Mode bit is clear, a switch from Active mode to Power Save mode only requires setting the PSM bit. When the WBPSM bit is set, a switch from Active mode to Power Save, Idle, or Halt mode is performed by setting the PSM, IDLE, or HALT bit, respectively, and then executing a WAIT instruction. Also, if the DMC or DHC bits are set, the high-frequency oscillator and PLL may be disabled only after a WAIT instruction is executed and the Power Save, Idle, or Halt mode is entered. 0 – Mode transitions may occur immediately. 1 – Mode transitions are delayed until the next WAIT instruction is executed. The Disable Main Clock bit may be used to disable the high-frequency oscillator in Power Save mode. In Active mode, the high-frequency oscillator is enabled without regard to the DMC value. The DMC bit is cleared by hardware when a hardware wake-up event is detected. This bit must be set in Idle and Halt modes. 0 – High-frequency oscillator is not disabled in Power Save mode, unless disabled by the HCC mechanism. 1 – High-frequency oscillator is disabled in Power Save mode. The Disable High-Frequency (PLL) Clock bit and may be used to disable the PLL in Power Save modes. When the DHC bit is clear (and PLLPWD = 0), the PLL is enabled in Power Save mode. If the DHC bit is set, the PLL is disabled in Power Save mode. The DHC bit is cleared by hardware when a hardware wake- HCCH 12.6.2 OMC The Oscillating Main Clock bit indicates whether the high-frequency oscillator is producing a stable clock. When the high-frequency oscillator is unavailable, the PMM will not switch to Active mode. 0 – High-frequency oscillator is unstable, disabled, or not oscillating. 1 – High-frequency oscillator is available. The Oscillating High Frequency (PLL) Clock bit indicates whether the PLL is producing a stable clock. Because the PMM tests the stability of the PLL clock to qualify power mode state transitions, a stable clock is indicated when the PLL is disabled. This removes the stability of the PLL clock from the test when the PLL is disabled. When the PLL is enabled but unstable, the PMM will not switch to Active mode. 0 – PLL is enabled but unstable. 1 – PLL is stable or disabled (CRCTRL.PLLPWD = 0). OHC 12.7 SWITCHING BETWEEN POWER MODES Switching from a higher to a lower power consumption mode is performed by writing an appropriate value to the Power Management Control/Status Register (PMMCR). Switching from a lower power consumption mode to the Active mode is usually triggered by a hardware interrupt. Figure 9 shows the four power consumption modes and the events that trigger a transition from one mode to another. Reset WBPSM = 1 & HALT = 1 & "WAIT" Power Management Status Register (PMMSR) The Management Status Register (PMMR) is a byte-wide, read/write register that provides status signals for the various clocks. The reset value of PMSR register bits 0 to 2 depend on the status of the clock sources monitored by the PMM. The upper 5 bits are clear after reset. The format of the register is shown below. Active Mode WBPSM = 0 & PSM = 1 or WBPSM = 1 & PSM = 1 & "WAIT" WBPSM = 1 & IDLE = 1 & "WAIT" Power Save Mode Idle Mode 7 3 Reserved 2 1 OHC OMC 0 HW Event OLC Halt Mode OLC HW Event The Oscillating Low Frequency Clock bit indicates whether the low-frequency oscillator is producing a stable clock. When the low-frequency oscillator is unavailable, the PMM will not switch to Power Save, Idle, or Halt mode. 0 – Low-frequency oscillator is unstable, disabled, or not oscillating. 1 – Low-frequency oscillator is available. HW Event Note: HW Event = MIWU wake-up or NMI DS422 Figure 9. Power Mode State Diagram Some of the power-up transitions are based on the occurrence of a wake-up event. An event of this type can be either a maskable interrupt or a non-maskable interrupt (NMI). All of the maskable hardware wake-up events are monitored by the Multi-Input Wake-Up (MIWU) Module, which is active in all modes. Once a wake-up event is detected, it is latched until an interrupt acknowledge cycle occurs or a reset is applied. A wake-up event causes a transition to the Active mode and restores normal clock operation, but does not start execution of the program. It is the interrupt handler associated 59 www.national.com CP3BT10 HCCM up event is detected. This bit must be set in Idle and Halt modes. 0 – PLL is not disabled in Power Save mode, unless disabled by the HCC mechanism or the PLLPWD bit. 1 – PLL is disabled in Power Save mode. The Hardware Clock Control for Main Clock bit may be used in Power Save and Idle modes to disable the high-frequency oscillator conditionally, depending on whether the Bluetooth LLC is in Sleep mode. The DMC bit must be clear for this mechanism to operate. The HCCM bit is automatically cleared when the device enters Active mode. 0 – High-frequency oscillator is disabled in Power Save or Idle mode only if the DMC bit is set. 1 – High-frequency oscillator is also disabled if the Bluetooth LLC is idle. The Hardware Clock Control for High-Frequency (PLL) bit may be used in Power Save and Idle modes to disable the PLL conditionally, depending on whether the Bluetooth LLC is in Sleep mode. The DHC bit and the CRCTRL.PLLPWD bit must be clear for this mechanism to operate. The HCCH bit is automatically cleared when the device enters Active mode. 0 – PLL is disabled in Power Save or Idle mode only if the DMC bit or the CRCTRL.PLLPWD bit is set. 1 – PLL is also disabled if the Bluetooth LLC is idle. CP3BT10 with the wake-up source (MIWU or NMI) that causes program execution to resume. 12.7.5 Software-Controlled Transition to Active Mode A transition from Power Save mode to Active mode can be accomplished by either a software command or a hardware wake-up event. The software method is to write a 0 to the A transition from Active mode to Power Save mode is perPMMCR.PSM bit. The value of the register bit changes only formed by writing a 1 to the PMMCR.PSM bit. The transition after the transition to the Active mode is completed. to Power Save mode is either initiated immediately or at execution of the next WAIT instruction, depending on the state If the high-frequency oscillator is disabled for Power Save operation, the oscillator must be enabled and allowed to staof the PMMCR.WBPSM bit. bilize before the transition to Active mode. To enable the For an immediate transition to Power Save mode (PMhigh-frequency oscillator, software writes a 0 to the PMMCR.WBPSM = 0), the CPU continues to operate using the MCR.DMC bit. Before writing a 0 to the PMMCR.PSM bit, low-frequency clock. The PMMCR.PSM bit becomes set software must first monitor the PMMSR.OMC bit to deterwhen the transition to the Power Save mode is completed. mine when the oscillator has stabilized. For a transition at the next WAIT instruction (PMMCR.WBPSM = 1), the CPU continues to operate in Active 12.7.6 Wake-Up Transition to Active Mode 12.7.1 Active Mode to Power Save Mode mode until it executes a WAIT instruction. At execution of the WAIT instruction, the device enters the Power Save mode, and the CPU waits for the next interrupt event. In this case, the PMMCR.PSM bit becomes set when it is written, even before the WAIT instruction is executed. 12.7.2 A hardware wake-up event switches the device directly from Power Save, Idle, or Halt mode to Active mode. Hardware wake-up events are: Non-Maskable Interrupt (NMI) Valid wake-up event on a Multi-Input Wake-Up channel Entering Idle Mode When a wake-up event occurs, the on-chip hardware perEntry into Idle mode is performed by writing a 1 to the PM- forms the following steps: MCR.IDLE bit and then executing a WAIT instruction. The 1. Clears the PMMCR.DMC bit, which enables the highPMMCR.WBPSM bit must be set before the WAIT instrucfrequency clock (if it was disabled). tion is executed. Idle mode can be entered only from the Ac- 2. Waits for the PMMSR.OMC bit to become set, which intive mode. The DHC and DMC bits must be set when dicates that the high-frequency clock is operating and entering Idle mode. is stable. 3. Clears the PMMCR.DHC bit, which enables the PLL. 12.7.3 Disabling the High-Frequency Clock 4. Waits for the PMMSR.OHC bit to become set. When the low-frequency oscillator is used to generate the 5. Switches the device into Active mode. Slow Clock, power consumption can be reduced further in the Power Save mode by disabling the high-frequency oscil- 12.7.7 Power Mode Switching Protection lator. This is accomplished by writing a 1 to the PM- The Power Management Module has several mechanisms MCR.DHC bit before executing the WAIT instruction that to protect the device from malfunctions caused by missing puts the device in the Power Save mode. The high-frequen- or unstable clock signals. cy clock is turned off only after the device enters the Power The PMMSR.OHC, PMMSR.OMC, and PMMSR.OLC bits Save mode. indicate the current status of the PLL, high-frequency oscilThe CPU operates on the low-frequency clock in Power lator, and low-frequency oscillator, respectively. Software Save mode. It can turn off the high-frequency clock at any can check the appropriate bit before switching to a power time by writing a 1 to the PMMCR.DHC bit. The high-fre- mode that requires the clock. A set status bit indicates an quency oscillator is always enabled in Active mode and al- operating, stable clock. A clear status bit indicates a clock ways disabled in Halt mode, without regard to the that is disabled, not available, or not yet stable. (Except in PMMCR.DHC bit setting. the case of the PLL, which has a set status bit when disImmediately after power-up and entry into Active mode, abled.) software must wait for the low-frequency clock to become During a power mode transition, if there is a request to stable before it can put the device in Power Save mode. It switch to a mode with a clear status bit, the switch is delayed should monitor the PMMSR.OLC bit for this purpose. Once until that bit is set by the hardware. this bit is set, Slow Clock is stable and Power Save mode When the system is built without an external crystal network can be entered. for the low-frequency clock, Main Clock is divided by a pres12.7.4 Entering Halt Mode caler factor to produce the low-frequency clock. In this situEntry into Halt mode is accomplished by writing a 1 to the ation, Main Clock is disabled only in the Idle and Halt PMMCR.HALT bit and then executing a WAIT instruction. modes, and cannot be disabled for the Power Save mode. The PMMCR.WBPSM bit must be set before the WAIT instruction is executed. Halt mode can be entered only from Active mode. The DHC and DMC bits must be set when entering Idle mode. www.national.com 60 Without an external crystal network for the low-frequency clock, the device comes out of Halt or Idle mode and enters Active mode with Main Clock driving Slow Clock. Note: For correct operation in the absence of a low-frequency crystal, X2CKI must be tied low (not left floating) so that the hardware can detect the absence of the crystal. The Multi-Input Wake-Up Unit (MIWU) monitors its 16 input channels for a software-selectable trigger condition. On detection of a trigger condition, the module generates an interrupt request and if enabled, a wake-up request. A wake-up request can be used by the power management unit to exit the Halt, Idle, or Power Save mode and return to the active mode. An interrupt request generates an interrupt to the CPU (interrupt IRQ2–IRQ5), which allows an interrupt handler to respond to MIWU events. The MIWU is active at all times, including the Halt mode. All device clocks are stopped in this mode. Therefore, detecting an external trigger condition and the subsequent setting of the pending bit are not synchronous to the System Clock. 13.1 MULTI-INPUT WAKE-UP REGISTERS Table 29 lists the MIWU unit registers. Table 29 Multi-Input Wake-Up Registers The wake-up event only activates the clocks and CPU, but does not by itself initiate execution of any code. It is the interrupt request associated with the MIWU that gets the CPU to start executing code, by jumping to the corresponding interrupt handler. Therefore, setting up the MIWU interrupt handler is essential for any wake-up operation. Name Address Description WKEDG FF FC80h Wake-Up Edge Detection Register WKENA FF FC82h Wake-Up Enable Register There are four interrupt requests that can be routed to the ICU as shown in Figure 10. Each of the 16 MIWU channels can be programmed to activate one of these four interrupt requests. WKIENA FF FC8Ch Wake-Up Interrupt Enable Register WKICTL1 FF FC84h Wake-Up Interrupt Control Register 1 WKICTL2 FF FC86h Wake-Up Interrupt Control Register 2 WKPND FF FC88h Wake-Up Pending Register WKPCL FF FC8Ah Wake-Up Pending Clear Register The MIWU channels are named WUI0 through WUI15, as shown in Table 28. Table 28 MIWU Sources MIWU Channel Source WUI0 TWM-T0OUT WUI1 ACCESS.bus WUI2 Reserved WUI3 MWCS WUI4 CTS WUI5 RXD WUI6 Bluetooth LLC WUI7 AAI SFS WUI8 USB Wake-Up WUI9 PI6 WUI10 PG0 WUI11 PG1 WUI12 PG2 WUI13 PG3 WUI14 PG6 WUI15 PG7 13.1.1 Wake-Up Edge Detection Register (WKEDG) The WKEDG register is a word-wide read/write register that controls the edge sensitivity of the MIWU channels. The WKEDG register is cleared upon reset, which configures all channels to be triggered on rising edges. The register format is shown below. 15 0 WKED WKED The Wake-Up Edge Detection bits control the edge sensitivity for MIWU channels. The WKED15:0 bits correspond to the WUI[15:0] channels, respectively. 0 – Triggered on rising edge (low-to-high transition). 1 – Triggered on falling edge (high-to-low transition). Each channel can be configured to trigger on rising or falling edges, as determined by the setting in the WKEDG register. Each trigger event is latched into the WKPND register. If a trigger event is enabled by its respective bit in the WKENA register, an active wake-up/interrupt signal is generated. Software can determine which channel has generated the active signal by reading the WKPND register. 61 www.national.com CP3BT10 13.0 Multi-Input Wake-Up CP3BT10 Peripheral BUS ........... 15 0 WKICTL 1-2 WKIENA WUI0 0 Encoder 4 EXINT3:0 to ICU 15 WUI15 WKEDG WKPND Wake-Up Signal To Power Mgt WKENA ........... 15 0 DS009 Figure 10. 13.1.2 Multi-Input Wake-Up Module Block Diagram Wake-Up Enable Register (WKENA) 13.1.4 The Wake-Up Enable (WKENA) register is a word-wide read/write register that individually enables or disables wake-up events from the MIWU channels. The WKENA register is cleared upon reset, which disables all wake-up/interrupt channels. The register format is shown below. 15 Wake-Up Interrupt Control Register 1 (WKICTL1) The WKICTL1 register is a word-wide read/write register that selects the interrupt request signal for the associated MIWU channels WUI7:0. At reset, the WKICTL1 register is cleared, which selects MIWU Interrupt Request 0 for all eight channels. The register format is shown below. 0 15 14 13 12 11 10 9 WKEN 8 7 6 5 4 3 2 1 0 WKIN WKIN WKIN WKIN WKIN WKIN WKIN WKIN TR7 TR6 TR5 TR4 TR3 TR2 TR1 TR0 WKEN 13.1.3 The Wake-Up Enable bits enable and disable the MIWU channels. The WKEN15:0 bits correspond to the WUI15:0 channels, respectively. 0 – MIWU channel wake-up events disabled. 1 – MIWU channel wake-up events enabled. Wake-Up Interrupt Enable Register (WKIENA) The WKIENA register is a word-wide read/write register that enables and disables interrupts from the MIWU channels. The register format is shown below. 15 0 WKIEN WKIEN The Wake-Up Interrupt Enable bits control whether MIWU channels generate interrupts. 0 – Interrupt disabled. 1 – Interrupt enabled. www.national.com 62 WKINTR The Wake-Up Interrupt Request Select fields select which of the four MIWU interrupt requests are activated for the corresponding channel. 00 – Selects MIWU interrupt request 0. 01 – Selects MIWU interrupt request 1. 10 – Selects MIWU interrupt request 2. 11 – Selects MIWU interrupt request 3. Wake-Up Interrupt Control Register 2 (WKICTL2) 13.1.7 The WKICTL2 register is a word-wide read/write register that selects the interrupt request signal for the associated MIWU channels WUI15 to WUI8. At reset, the WKICTL2 register is cleared, which selects MIWU Interrupt Request 0 for all eight channels. The register format is shown below. 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 13.1.6 The Wake-Up Pending Clear (WKPCL) register is a wordwide write-only register that lets the CPU clear bits in the WKPND register. Writing a 1 to a bit position in the WKPCL register clears the corresponding bit in the WKPND register. Writing a 0 has no effect. Do not modify this register with instructions that access the register as a read-modify-write operand, such as the bit manipulation instructions. Reading this register location returns undefined data. Therefore, do not use a read-modify-write sequence (such as the SBIT instruction) to set individual bits. Do not attempt to read the register, then perform a logical OR on the register value. Instead, write the mask directly to the register address. The register format is shown below. 0 WKIN WKIN WKIN WKIN WKIN WKIN WKIN WKIN TR15 TR14 TR13 TR12 TR11 TR10 TR9 TR8 WKINTR The Wake-Up Interrupt Request Select fields select which of the four MIWU interrupt re15 quests are activated for the corresponding channel. 00 – Selects MIWU interrupt request 0. 01 – Selects MIWU interrupt request 1. 10 – Selects MIWU interrupt request 2. WKCL 11 – Selects MIWU interrupt request 3. Wake-Up Pending Register (WKPND) The WKPND register is a word-wide read/write register in which the Multi-Input Wake-Up module latches any detected trigger conditions. The CPU can only write a 1 to any bit position in this register. If the CPU attempts to write a 0, it has no effect on that bit. To clear a bit in this register, the CPU must use the WKPCL register. This implementation prevents a potential hardware-software conflict during a read-modify-write operation on the WKPND register. 13.2 0 WKPD WKPD 0 WKCL Writing 1 to a bit clears it. 0 – Writing 0 has no effect. 1 – Writing 1 clears the corresponding bit in the WKPD register. PROGRAMMING PROCEDURES To set up and use the Multi-Input Wake-Up function, use the following procedure. Performing the steps in the order shown will prevent false triggering of a wake-up condition. This same procedure should be used following a reset because the wake-up inputs are left floating, resulting in unknown data on the input pins. This register is cleared upon reset. The register format is shown below. 15 Wake-Up Pending Clear Register (WKPCL) 1. Clear the WKENA register to disable the MIWU channels. 2. Write the WKEDG register to select the desired type of edge sensitivity (clear for rising edge, set for falling edge). 3. Set all bits in the WKPCL register to clear any pending bits in the WKPND register. 4. Set up the WKICTL1 and WKICTL2 registers to define the interrupt request signal used for each channel. 5. Set the bits in the WKENA register corresponding to the wake-up channels to be activated. The Wake-Up Pending bits indicate which MIWU channels have been triggered. The WKPD[15:0] bits correspond to the WUI[15:0] channels. Writing 1 to a bit sets it. To change the edge sensitivity of a wake-up channel, use 0 – Trigger condition did not occur. 1 – Trigger condition occurred. the following procedure. Performing the steps in the order shown will prevent false triggering of a wake-up/interrupt condition. 1. Clear the WKENA bit associated with the input to be reprogrammed. 2. Write the new value to the corresponding bit position in the WKEDG register to reprogram the edge sensitivity of the input. 3. Set the corresponding bit in the WKPCL register to clear the pending bit in the WKPND register. 4. Set the same WKENA bit to re-enable the wake-up function. 63 www.national.com CP3BT10 13.1.5 CP3BT10 14.0 Input/Output Ports Each device has up to 40 software-configurable I/O pins, organized into five 8-bit ports. The ports are named Port B, Port C, Port G, Port H, and Port I. In addition to their general-purpose I/O capability, the I/O pins of Ports G, H, and I have alternate functions for use with on-chip peripheral modules such as the UART or the Multi-Input Wake-Up module. The alternate functions of all I/O pins are shown in Table 2. Different pins within the same port can be individually configured to operate in different modes. Figure 11 is a diagram showing the I/O port pin logic. The register bits, multiplexers, and buffers allow the port pin to be configured into the various operating modes.The output buffer is a TRI-STATE buffer with weak pull-up capability. The weak pull-up, if used, prevents the port pin from going to an undefined state when it operates as an input. Ports B and C are used as the 16-bit data bus when an external bus is enabled (100-pin devices only). This alternate function is selected by enabling the DEV or ERE operating environments, not by programming the port registers. To reduce power consumption, input buffers configured for general-purpose I/O are only enabled when they are read. When configured for an alternate function, the input buffers are enabled continuously. To minimize power consumption, The I/O pin characteristics are fully programmable. Each pin input signals to enabled buffers must be held within 0.2 volts can be configured to operate as a TRI-STATE output, push- of the VCC or GND voltage. pull output, weak pull-up input, or high-impedance input. The electrical characteristics and drive capabilities of the input and output buffers are described in Section 27.0. D Q D Q D Q PxALTS Register VCC PxALT Register Weak Pull-Up Enable PxWKPU Register Alt. A Device Direction Output Enable Alt. B Device Direction D Q PxDIR Register Pin Alt. A Device Data Outout Data Out Alt. B Device Data Outout D Q PxDOUT Register Alt. A Data Input Data In PxDIN Register Alt. B Data Input 1 Data In Read Strobe DS190 Analog Input Figure 11. I/O Port Pin Logic Each port has an associated set of memory-mapped regis ters used for controlling the port and for holding the port da ta: 14.1 PORT REGISTERS www.national.com 64 PxALT: Port alternate function register PxALTS: Port alternate function select register PxDIR: Port direction register PxDIN: Port data input register PxDOUT: Port data output register PxWPU: Port weak pull-up register PxHDRV: Port high drive strength register Table 30 Port Registers Name PBALT PBDIR PBDIN PBDOUT PBWPU PBHDRV PBALTS PCALT PCDIR PCDIN PCDOUT PCWPU PCHDRV Address FF FB00h FF FB02h FF FB04h FF FB06h FF FB08h FF FCC0h Port H Alternate Function Register PHDIR FF FCC2h Port H Direction Register PHDIN FF FCC4h Port H Data Input Register PHDOUT FF FCC6h Port H Data Output Register PHWPU FF FCC8h Port H Weak Pull-Up Register PHHDRV FF FCCAh Port H High Drive Strength Register PHALTS FF FCCCh Port H Alternate Function Select Register PIALT FF FEE0h Port I Alternate Function Register PIDIR FF FEE2h Port I Direction Register PIDIN FF FEE4h Port I Data Input Register PIDOUT FF FEE6h Port I Data Output Register PIWPU FF FEE8h Port I Weak Pull-Up Register PIHDRV FF FEEAh Port I High Drive Strength Register PIALTS FF FEECh Port I Alternate Function Select Register Port B Data Input Register Port B Data Output Register Port B Weak Pull-Up Register FF FB0Ch Port C Alternate Function Register Port C Direction Register FF FB14h Port C Data Input Register FF FB16h Port C Data Output Register FF FB18h Port C Weak Pull-Up Register Port C High Drive Strength Register FF FB1Ch Port C Alternate Function Select Register PGALT FF FCA0h Port G Alternate Function Register PGDIR FF FCA2h Port G Direction Register PGDIN FF FCA4h Port G Data Input Register PGDOUT FF FCA6h Port G Data Output Register PGWPU FF FCA8h Port G Weak Pull-Up Register PGHDRV FF FCAAh Port G High Drive Strength Register PGALTS FF FCACh Port G Alternate Function Select Register PCALTS PHALT Port B Direction Register Port B Alternate Function Select Register FF FB1Ah Description Port B Alternate Function Register Port B High Drive Strength Register FF FB12h Address Description FF FB0Ah FF FB10h Name In the descriptions of the ports and port registers, the lowercase letter “x” represents the port designation, either B, C, G, H, or I. For example, “PxDIR register” means any one of the port direction registers: PBDIR, PCDIR, PGDIR, PHDIR, or PIDIR. All of the port registers are byte-wide read/write registers, except for the port data input registers, which are read-only registers. Each register bit controls the function of the corresponding port pin. For example, PGDIR.2 (bit 2 of the PGDIR register) controls the direction of port pin PG2. 65 www.national.com CP3BT10 Table 30 Port Registers CP3BT10 14.1.1 14.1.3 Port Alternate Function Register (PxALT) The PxALT registers control whether the port pins are used for general-purpose I/O or for their alternate function. Each port pin can be controlled independently. A clear bit in the alternate function register causes the corresponding pin to be used for general-purpose I/O. In this configuration, the output buffer is controlled by the direction register (PxDIR) and the data output register (PxDOUT). The input buffer is visible to software as the data input register (PxDIN). A set bit in the alternate function register (PxALT) causes the corresponding pin to be used for its peripheral I/O function. When the alternate function is selected, the output buffer data and TRI-STATE configuration are controlled by signals from the on-chip peripheral device. Port Data Input Register (PxDIN) The data input register (PxDIN) is a read-only register that returns the current state on each port pin. The CPU can read this register at any time even when the pin is configured as an output. 7 0 PxDIN PxDIN The PxDIN bits indicate the state on the corresponding port pin. 0 – Pin is low. 1 – Pin is high. 14.1.4 Port Data Output Register (PxDOUT) A reset operation clears the port alternate function registers, which initializes the pins as general-purpose I/O ports. The data output register (PxDOUT) holds the data to be This register must be enabled before the corresponding al- driven on output port pins. In this configuration, writing to the register changes the output value. Reading the register ternate function is enabled. returns the last value written to the register. 7 A reset operation leaves the register contents unchanged. At power-up, the PxDOUT registers contain unknown values. 0 PxALT PxALT 14.1.2 7 The PxALT bits control whether the corresponding port pins are general-purpose I/O ports or are used for their alternate function by an on-chip peripheral. PxDOUT 0 – General-purpose I/O selected. 1 – Alternate function selected. Port Direction Register (PxDIR) The port direction register (PxDIR) determines whether each port pin is used for input or for output. A clear bit in this register causes the corresponding pin to operate as an input, which puts the output buffer in the high-impedance state. A set bit causes the pin to operate as an output, which enables the output buffer. 14.1.5 0 PxDOUT The PxDOUT bits hold the data to be driven on pins configured as outputs in general-purpose I/O mode. 0 – Drive the pin low. 1 – Drive the pin high. Port Weak Pull-Up Register (PxWPU) The weak pull-up register (PxWPU) determines whether the port pins have a weak pull-up on the output buffer. The pullup device, if enabled by the register bit, operates in the genA reset operation clears the port direction registers, which eral-purpose I/O mode whenever the port output buffer is disabled. In the alternate function mode, the pull-ups are alinitializes the pins as inputs. ways disabled. 7 A reset operation clears the port weak pull-up registers, which disables all pull-ups. 0 PxDIR 7 PxDIR The PxDIR bits select the direction of the corresponding port pin. 0 – Input. 1 – Output. www.national.com 66 0 PxWPU PxWPU The PxWPU bits control whether the weak pull-up is enabled. 0 – Weak pull-up disabled. 1 – Weak pull-up enabled. Port High Drive Strength Register (PxHDRV) Table 31 The PxHDRV register is a byte-wide, read/write register that controls the slew rate of the corresponding pins. The high drive strength function is enabled when the corresponding bits of the PxHDRV register are set. In both GPIO and alternate function modes, the drive strength function is enabled by the PxHDRV registers. At reset, the PxHDRV registers are cleared, making the ports low speed. 7 0 PxHDRV PxHDRV 14.1.7 The PxHDRV bits control whether output pins are driven with slow or fast slew rate. 0 – Slow slew rate. 1 – Fast slew rate. Port Alternate Function Select Register (PxALTS) The PxALTS register selects which of two alternate functions are selected for the port pin. These bits are ignored unless the corresponding PxALT bits are set. Each port pin can be controlled independently. 7 0 PxALTS PxALTS The PxALTS bits select among two alternate functions. Table 31 shows the mapping of the PxALTS bits to the alternate functions. Unused PxALTS bits must be clear. 14.2 Alternate Function Select Port Pin PxALTS = 0 PxALTS = 1 PG0 RXD WUI10 PG1 TXD WUI11 PG2 RTS WUI12 PG3 CTS WUI13 PG4 Reserved TB PG5 SRFS NMI PG6 Reserved WUI14 PG7 Reserved WUI15 PH0 MSK TIO1 PH1 MDIDO TIO2 PH2 MDODI TIO3 PH3 MWCS TIO4 PH4 SCK TIO5 PH5 SFS TIO6 PH6 STD TIO7 PH7 SRD TIO8 PI0 RFSYNC Reserved PI1 RFCE Reserved PI2 BTSEQ1 SRCLK PI3 SCLK Reserved PI4 SDAT Reserved PI5 SLE Reserved PI6 WUI9 BTSEQ2 PI7 TA BTSEQ3 OPEN-DRAIN OPERATION A port pin can be configured to operate as an inverting open-drain output buffer. To do this, the CPU must clear the bit in the data output register (PxDOUT) and then use the port direction register (PxDIR) to set the value of the port pin. With the direction register bit set (direction = out), the value zero is forced on the pin. With the direction register bit clear (direction = in), the pin is placed in the TRI-STATE mode. If desired, the internal weak pull-up can be enabled to pull the signal high when the output buffer is in TRISTATE mode. 67 www.national.com CP3BT10 14.1.6 CP3BT10 15.0 Bluetooth Controller The integrated hardware Bluetooth Lower Link Controller Figure 13 shows the interface between the CP3BT10 and (LLC) complies to the Bluetooth Specification Version 1.1 the LMX5252 radio chip. and integrates the following functions: +2.8V 4.5K-byte dedicated Bluetooth data RAM 1K-byte dedicated Bluetooth Sequencer RAM Support of all Bluetooth 1.1 packet types Support for fast frequency hopping of 1600 hops/s Access code correlation and slot timing recovery circuit Power Management Control Logic BlueRF-compatible interface to connect with National’s LMX5252 and other RF transceiver chips IOVCC RFDATA PI1/RFCE BBDATA_1 BXTLEN CP3BT10 LMX5252 PI2/BTSEQ1 For a detailed description of the interface to the LMX5252, consult the LMX5252 data sheet which is available from the National Semiconductor wireless group. National provides software libraries for using the Bluetooth LLC. Documentation for the software libraries is also available from National Semiconductor. 15.1 VCC RF INTERFACE BPKTCTL PI3/SCLK BDCLK PI4/SDAT BDDATA PI5/SLE BDEN# X1CKI/BBCLK BRCLK The CP3BT10 interfaces to the LMX5251 or LMX5252 radio chips though the RF interface. Figure 12 shows the interface between the CP3BT10 and the LMX5251 radio chip. DS317 Figure 13. LMX5252 Interface VCC IOVCC VDD_DIG_IN The CP3BT10 implements a BlueRF-compatible interface, which may be used with other RF transceiver chips. RFDATA TX_RX_DATA 15.1.1 PI0/RFSYNC CP3BT10 PI1/RFCE The RF interface signals are grouped as follows: TX_RX_SYNC LMX5251 CE PI3/SCLK CCB_CLOCK PI4/SDAT CCB_DATA PI5/SLE CCB_LATCH X1CKI/BBCLK BBP_CLOCK Modem Signals (BBCLK, RFDATA, and RFSYNC) Control Signal (RFCE) Serial Interface Signals (SCLK, SDAT, and SLE) Bluetooth Sequencer Status Signals (BTSEQ1, BTSEQ2, and BTSEQ2) X1CKI/BBCLK The X1CKI/BBCLK pin is the input signal for the 12-MHz clock signal. The radio chip uses this signal internally as the 12× oversampling clock and provides it externally to the CP3BT10 for use as the Main Clock. DS011 Figure 12. RF Interface Signals RFDATA LMX5251 Interface The RFDATA signal is the multiplexed Bluetooth data receive and transmit signal. The data is provided at a bit rate of 1Mbit/s with 12× oversampling, synchronized to the 12 MHz BBCLK. The RFDATA signal is a dedicated RF interface pin. This signal is driven to a logic high level after reset. RFSYNC In receive mode (data direction from the radio chip to the CP3BT10), the RFSYNC signal acts as the frequency correction/DC compensation circuit control output to the radio chip. The RFSYNC signal is driven low throughout the correlation phase and driven high when synchronization to the received access code is achieved. In transmit mode (data direction from the CP3BT10 to the radio chip), the RFSYNC signal enables the RF output of the radio chip. When the RFSYNC pin is driven high, the RF transmitter circuit of the radio chip is enabled, correspondwww.national.com 68 SDAT Data The SDAT signal is the multiplexed serial data receive and transmit path between the radio chip and the CP3BT10. The data field is used to transfer data to or from a radio chip register. The timing is modified for reads, to transfer control over the data signal from the CP3BT10 to the radio chip. The SDAT signal is the alternate function of the general-purpose I/O pin PI4. At reset, this pin is in TRI-STATE mode. Software must enable the alternate function of the PI4 pin to give control over this signal to the RF interface. Figure 14 shows the serial interface protocol format. 15 0 SLE Data[15:0] The SLE pin is the serial load enable output of the serial interface of the CP3BT10. 24 During write operations (to the radio chip registers), the data received by the shift register of the radio chip is copied into the address register on the next rising edge of SCLK after the SLE signal goes high. During read operations (read from the registers), the radio chip releases the SDAT line on the next rising edge of SCLK after the SLE signal goes high. 22 Header[2:0] 21 R/W 20 16 Address[4:0] Figure 14. Serial Interface Protocol Format Data is transferred on the serial interface with the most significant bit (MSB) first. SLE is the alternate function of the general-purpose I/O pin PI5. At reset, this pin is in TRI-STATE mode. Software must enable the alternate function of the PI5 pin to give control over this signal to the RF interface. 69 www.national.com CP3BT10 ing to the settings of the power control register in the radio BTSEQ[3:1] chip. The BTSEQ[3:1] signals indicate internal states of the BlueThe RFSYNC signal is the alternate function of the general- tooth sequencer, which are used for interfacing to some expurpose I/O pin PI0. At reset, this pin is in TRI-STATE mode. ternal devices. Software must enable the alternate function of the PI0 pin to 15.2 SERIAL INTERFACE give control over this signal to the RF interface. The radio chip register set can be accessed by the RFCE CP3BT10 through the serial interface. The serial interface The RFCE signal is the chip enable output to the external uses three pins of the RF interface: SDAT, SCLK, and SLE. RF chip. When the RFCE signal is driven high, the RF chip The serial interface of the CP3BT10 always operates as the power is controlled by the settings of its power control regmaster, providing the shift clock (SCLK) and load enable isters. When the RFCE signal is driven low, the RF chip is (SLE) signal to the radio chip. The radio chip always acts as powered-down. However, the serial interface is still operathe slave. tional and the CP3BT10 can still access the RF chip internal A 25-bit shift protocol is used to perform read/write accesscontrol registers. es to the radio chip internal registers. The complete protocol The RFCE signal is the alternate function of the generalis comprised of the following sections: purpose I/O pin PI1. At reset, this pin is in TRI-STATE mode. Software must enable the alternate function of the PI1 pin to 3-bit Header Field Read/Write Bit give control over this signal to the RF interface. 5-bit Address Field During Bluetooth power-down phases, the CP3BT10 pro 16-bit Data Field vides a mechanism to reduce the power consumption of an external RF chip by driving the RFCE signal of the RF inter- Header face to a logic low level. This feature is available when the The 3-bit header contains the fixed data 101b (except for Power Management Module of the CP3BT10 has enabled Fast Write Operations). the Hardware Clock Control mechanism. Read/Write Bit SCLK The header is followed by the read/write control bit (R/W). If The SCLK signal is the serial interface shift clock output. the Read/Write bit is clear, a write operation is performed The CP3BT10 always acts as the master of the serial inter- and the 16-bit data portion is copied into the addressed raface and therefore always provides the shift clock. The dio chip register. SCLK signal is the alternate function of the general-purpose I/O pin PI3. At reset, this pin is in TRI-STATE mode. Soft- Address ware must enable the alternate function of the PI3 pin to The address field is used to select one of the radio chip ingive control over this signal to the RF interface. ternal registers. CP3BT10 Write Operation When the R/W bit is clear, the 16 bits of the data field are shifted out of the CP3BT10 on the falling edge of SCLK. Data is sampled by the radio chip on the rising edge of SCLK. When SLE is high, the 16-bit data are copied into the radio chip register on the next rising edge of SCLK. The data is loaded in the appropriate radio chip register depending on the state of the four address bits, Address[4:0]. Figure 15 shows the timing for the write operation. SDAT H2 H1 H0 W A4 A3 A2 A1 A0 D15 D14 D0 used to address the write-only registers of the radio chip . Fast writes load the same physical register as the corresponding normal write operation. For the power control and CMOS output registers of the RF chip, it is only necessary to transmit a total of 8 bits (3 address bits and 5 data bits), because the remaining eight bits are unused. While the FW bit is set, normal Read/Write operations are still valid and may be used to access non-time-critical control registers. Figure 17 shows the timing for a 16-bit FastWrite transaction, and Figure 18 shows the timing for an 8bit Fast-Write transaction. SCLK SDAT SLE A2 A1 A0 D12 D11 D10 D9 D8 D7 D6 D1 D0 SCLK DS012 SLE Figure 15. Serial Interface Write Timing DS014 Read Operation When the R/W bit is set, data is shifted out of the radio chip on the rising edge of SCLK. Data is sampled by the CP3BT10 on the falling edge of SCLK. On reception of the read command (R/W = 1), the radio chip takes control of the serial interface data line. The received 16-bit data is loaded by the CP3BT10 after the first falling edge of SCLK when SLE is high. When SLE is high, the radio chip releases the SDAT line again on the next rising edge of SCLK. The CP3BT10 takes control of the SDAT line again after the following rising edge of SCLK. Which radio chip register is read, depends on the state of the four address bits, Address[4:0]. The transfer is always 16 bits, without regard to the actual size of the register. Unimplemented bits contain undefined data. Figure 16 shows the timing for the read operation. Figure 17. Serial Interface 16-bit Fast-Write Timing SDAT A2 A1 A0 D12 D11 D10 D9 D8 SCLK SLE DS015 Figure 18. Serial Interface 8-bit Fast-Write Timing 32-Bit Write Operation On the LMX5252, a 32-bit register is loaded by writing to the same register address twice. The first write loads the high word (bits 31:16), and the second write loads the low word (bits 15:0). The two writes must be separated by at least two clock cycles. For a 4-MHz clock, the minimum separation time is 500 ns. SDAT Floating Slave drives SDAT Master drives SDAT SDAT H2 H1 H0 R A4 A3 A2 A1 A0 D15 D1 D0 The value read from a 32-bit register is a counter value, not the contents of the register. The counter value indicates which words have been written. If the high word has been written, the counter reads as 0000h. If both words have been written, the counter reads as 0001h. The value returned by reading a 32-bit register is independent of the contents of the register. SCLK SLE DS013 Figure 16. Serial Interface Read Timing Figure 19 and Figure 20 show the timing for 32-bit register writing and reading. Fast-Write Operation An enhanced serial interface mode including fast write capability is enabled when the FW bit in the radio chip is set. The order for accessing the registers is from high to low: 17, This bit activates a mode with decreased addressing and 15, 14, 12, 11, 10, 9, 8, 7, 6, 5, 4, 2, and 1. These registers control overhead, which allows fast loading of time-critical must be written during the initialization of the LMX5252. registers during normal operation. When the FW bit is set, the 3-bit header may have a value other than 101b, and it is www.national.com 70 H2 H1 H0 W A4 A3 A2 A1 A0 D31 D30 D16 H2 H1 H0 W A4 A3 A2 A1 A0 D15 D14 CP3BT10 SDAT D0 SCLK >500 ns SLE DS322 Figure 19. 32-Bit Write Timing SDAT H2 H1 H0 R A4 A3 A2 A1 A0 D31 D16 H2 H1 H0 R A4 A3 A2 A1 A0 D15 D0 SCLK >500 ns SLE DS323 Figure 20. 32-Bit Read Timing An example of a 32-bit write is shown in Table 32. In this example, the 32-bit value FFFF DC04h is written to register address 0Ah. In cycle 1, the high word (FFFFh) is written. In the first part of cycle 2, the CP3BT10 drives the header, R/ W bit, and register address for a read cycle. In the second part of cycle 2, the LMX5252 drives the counter value. The Table 32 Cycle 1 counter value is 0, which indicates one word has been written. In cycle 3, the low word (DC04h) is written. In the first part of cycle 4, the CP3BT10 drives the header, R/W bit, and register address for a read cycle. In the second part of cycle 4, the LMX5252 drives the counter value. The counter value is 1, which indicates two words have been written. Example of 32-Bit Write with Interleaved Reads Serial Data on SDAT Description 101 0 01010 1111111111111111 Write cycle driven by CP3BT10. Data is FFFFh. Address is 0Ah. 101 1 01010 First part of read cycle driven by CP3BT10. Address is 0Ah. 2 0000000000000000 Second part of read cycle driven by LMX5252. Counter value is 0. 3 101 0 01010 1101110000000100 Write cycle driven by CP3BT10. Data is DC04h. Address is 0Ah. 101 1 01010 First part of read cycle driven by CP3BT10. Address is 0Ah. 4 0000000000000001 Second part of read cycle driven by LMX5252. Counter value is 1. 71 www.national.com CP3BT10 15.3 LMX5251 POWER-UP SEQUENCE 15.4 To power-up a Bluetooth system based on the CP3BT10 and LMX5251 devices, the following sequence must be performed: 1. Apply VDD to the LMX5251. 2. Apply IOVCC and VCC to the CP3BT10. 3. Drive the RESET# pin of the LMX5251 high a minimum of 2 ms after the LMX5251 and CP3000 supply rails are powered up. This resets the LMX5251 and CP3BT10. 4. After internal Power-On Reset (POR) of the CP3BT10, the RFDATA pin is driven high. The RFCE, RFSYNC, and SDAT pins are in TRI-STATE mode. Internal pullup/pull-down resistors on the CCB_CLOCK (SCLK), CCB_DATA (SDAT), CCB_LATCH (SLE), and TX_RX_SYNC (RFSYNC) inputs of the LMX5251 pull these signals to states required during the power-up sequence. 5. When the RFDATA pin is driven high, the LMX5251 enables its oscillator. After an oscillator start-up delay, the LMX5251 drives a stable 12-MHz BBP_CLOCK (BBCLK) to the CP3BT10. 6. The Bluetooth baseband processor on the CP3BT10 now directly controls the RF interface pins and drives the logic levels required during the power-up phase. When the RFCE pin is driven high, the LMX5251 switches from “power-up” to “normal” mode and disables the internal pull-up/pull-down resistors on its RF interface inputs. 7. In “normal” mode, the oscillator of the LMX5251 is controlled by the RFCE signal. Driving RFCE high enables the oscillator, and the LMX5251 drives its BBP_CLOCK (BBCLK) output. LMX5252 POWER-UP SEQUENCE A Bluetooth system based on the CP3BT10 and LMX5252 devices has the following states: Off—When the LMX5252 enters Off mode, all configuration data is lost. In this state, the LMX5252 drives BPOR low. Power-Up—When the power supply is on and the LMX5252 RESET# input is high, the LMX5252 starts up its crystal oscillator and enters Power-Up mode. After the crystal oscillator is settled, the LMX5252 sends four clock cycles on BRCLK (BBCLK) before driving BPOR high. RF Init—The baseband controller on the CP3BT10 now drives RFCE high and takes control of the crystal oscillator. The baseband performs all the needed initialization (such as writing the registers in the LMX5252 and crystal oscillator trim). Idle—The baseband controller on the CP3BT10 drives RFDATA low when the initialization is ready. The LMX5252 is now ready to start transmitting, receiving, or enter Sleep mode. Sleep—The LMX5252 can be forced into Sleep mode at any time by driving RFCE low. All configuration settings are kept, only the Bluetooth low power clock is running (B3k2). Wait XTL—When RFCE goes high, the crystal oscillator becomes operational. When it is stable, the LMX5252 enters Idle mode and drives BRCLK (BBCLK). Any State RESET# = Low or Power is cycled VDDLMX5251 VCCCP3000 IOVCCCP3000 RESET#LMX5251 Off tPTOR RESET# = High and Power is On RESETCP3000 RFCE Low BBCLK Low RFDATA High RFSYNC Low SDAT Low SCLK Low Any State After RF Init RFCE = Low High Wait for Crystal Osc. To Stabilize Power-Up Sleep Crystal Osc. Stable RFCE = High RFDATA = Don't Care Write Registers RF Init Wait for Crystal Osc. To Stabilize RFCE = High Wait XTL SLE LMX5251 Oscillator Start-Up CP3000 LMX5251 Initialization Initialization LMX5251 in Power-Up Mode Figure 21. Standby Crystal Osc. Stable Active Idle LMX5251 in Normal Mode DS324 DS016 Figure 22. LMX5252 Power States LMX5251 Power-Up Sequence The power-up sequence for a Bluetooth system based on the CP3BT10 and LMX5252 devices is shown in Figure 23. www.national.com 72 RESET RFDATA t5 t3 RFCE BBCLK BPOR t1 t2 B3k2 t4 SLE SCLK CPU SDAT DS321 Figure 23. 15.5 System Clock LMX5252 Power-Up Sequence HCC BLUETOOTH SLEEP MODE BT LCC Clock The Bluetooth controller is capable of putting itself into a sleep mode for a specified number of Slow Clock cycles. In this mode, the controller clocks are stopped internally. The only circuitry which remains active are two counters (counter N and counter M) running at the Slow Clock rate. These counters determine the duration of the sleep mode. HCC The sequence of events when entering the LLC sleep mode is as follows: 1. The current Bluetooth counter contents are read by the CPU. 2. Software “estimates” the Bluetooth counter value after leaving the sleep mode. 3. The new Bluetooth counter value is written into the Bluetooth counter register. 4. The Bluetooth sequencer RAM is updated with the code required by the Bluetooth sequencer to enter/exit Sleep mode. 5. The Bluetooth sequencer RAM and the Bluetooth LLC registers are switched from the System Clock domain to the local 12 MHz Bluetooth clock domain. At this point, the Bluetooth sequencer RAM and Bluetooth LLC registers cannot be updated by the CPU, because the CPU no longer has access to the Bluetooth LLC. 6. Hardware Clock Control (HCC) is enabled, and the CP3BT10 enters a power-saving mode (Power Save or Idle mode). While in Power Save mode, the Slow Clock is used as the System Clock. While in Idle mode, the System Clock is turned off. 7. The Bluetooth sequencer checks if HCC is enabled. If HCC is enabled, the sequencer asserts HCC to the PMM. On the next rising edge of the low-frequency clock, the 1MHz clock and the 12 MHz clock are stopped locally within the Bluetooth LLC. At this point, the Bluetooth sequencer is stopped. 8. The M-counter starts counting. After M + 1 Slow Clock cycles, the HCC signal to the PMM is deasserted. 9. The PMM restarts the 12 MHz Main Clock (and the PLL, if required). The N-counter starts counting. After N + 1 Slow Clock cycles, the Bluetooth clocks (1 MHz Active Power Save Active Stopped/Slow Enabled Disabled System Clock Main Clock Asserted Deasserted Active 12 MHz Main Clock Stopped 1 MHz/12 MHz BT Clock Stopped Sequencer Active Active Stopped Start-up CPU Prepare for Sleep Mode N M CPU Handles Wake-Up IRQ from MIWU DS017 Figure 24. 15.6 Bluetooth Sleep Mode Sequence BLUETOOTH GLOBAL REGISTERS Table 33 shows the memory map of the Bluetooth LLC global registers. Table 33 Memory Map of Bluetooth Global Registers Address (offset from 0E F180h) Description 0000h–0048h Global LLC Configuration 0049h–007Fh Unused 15.7 BLUETOOTH SEQUENCER RAM The sequencer RAM is a 1K memory-mapped section of RAM that contains the sequencer program. This RAM can be read and written by the CPU in the same way as the Static RAM space and can also be read by the sequencer in the Bluetooth LLC. Arbitration between these devices is performed in hardware. 73 www.national.com CP3BT10 and 12 MHz) are turned on again. The Bluetooth sequencer starts operating. 10. The Bluetooth sequencer waits for the completion of the sleep mode. When completed, the Bluetooth sequencer asserts a wake-up signal to the MIWU (see Section 13.0). 11. The PMM switches the System Clock to the high-frequency clock and the CP3BT10 enters Active mode again. HCC is disabled. The Bluetooth sequencer RAM and Bluetooth LLC registers are switched back from the local 12 MHz Bluetooth clock to the System Clock. At this point, the Bluetooth sequencer RAM and Bluetooth LLC registers are once again accessible by the CPU. If enabled, an interrupt is issued to the CPU. CP3BT10 15.8 BLUETOOTH SHARED DATA RAM The shared data RAM is a 4.5K memory-mapped section of RAM that contains the link control data, RF programming look-up table, and the link payload. This RAM can be read and written in the same way as the Static RAM space and can also be read by the sequencer in the Bluetooth LLC. Arbitration between these devices is performed in hardware. Table 34 shows the memory map of the Bluetooth LLC shared Data RAM. Table 34 Memory Map of Bluetooth Shared RAM Address Description 0000h–01D9h RF Programming Look-up Table 01DAh–01FFh Unused 0200h–023Fh Link Control 0 0240h–027Fh Link Control 1 0280h–02BFh Link Control 2 02C0h–02FFh Link Control 3 0300h–033Fh Link Control 4 0340h–037Fh Link Control 5 0380h–03BFh Link Control 6 03C0h–03FFh Link Control 7 0400h–11FFh Link Payload 0–6 www.national.com 74 The USB node is an integrated USB node controller that fea- NodeOperational tures enhanced DMA support with many automatic data This is the normal operating state of the node. In this state, handling features. It is compatible with USB specification the node is configured for operation on the USB. versions 1.0 and 1.1. NodeSuspend It integrates the required USB transceiver, a Serial Interface Engine (SIE), and USB endpoint (EP) FIFOs. Seven end- A USB node is expected to enter NodeSuspend state when point pipes are supported: one for the mandatory control 3 ms have elapsed without any detectable bus activity. The endpoint and six to support interrupt, bulk, and isochronous USB node looks for this event and signals it by setting the endpoints. Each endpoint pipe has a dedicated FIFO, 8 SD3 bit in the ALTEV register, which causes an interrupt, to bytes for the control endpoint and 64 bytes for the other end- be generated (if enabled). Software should respond by putting the USB node in the NodeSuspend state. points. The USB node can resume normal operation under software control in response to a local event in the device. It can 16.1.1 Line Condition Detection wake up the USB bus via a NodeResume, or when detectAt any given time, the USB node is in one of the following ing a resume command on the USB bus, which signals an interrupt to the CPU. states 16.1 FUNCTIONAL STATES NodeResume Table 35 State Descriptions State If the host has enabled remote wake-ups from the node, the USB node can initiate a remote wake-up. Descriptions NodeOperational Normal operation NodeSuspend Device operation suspend due to USB inactivity NodeResume Device wake-up from suspended state NodeReset Device reset The NodeSuspend, NodeResume, or NodeReset line condition causes a transition from one operating state to another. These conditions are detected by specialized hardware and reported in the Alternate Event (ALTEV) register. If interrupts are enabled, an interrupt is generated on the occurrence of any of the specified conditions. In addition to the dedicated input to the ICU for generating interrupts on these USB state changes, a wake-up signal is sent to the MIWU (see Section 13.0) when any activity is detected on the USB, if the bus was in the Idle state and the USB node is in the NodeSuspend state. The MIWU can be programmed to generate an edge-triggered interrupt when this occurs. Once software detects the event, which wakes up the bus, it releases the USB node from NodeSuspend state by initiating a NodeResume on the USB using the NFSR register. The node software must ensure at least 5 ms of Idle on the USB. While in NodeResume state, a constant “K” is signalled on the USB. This should last for at least 1 ms and no more than 5 ms, after which the USB host should continue sending the NodeResume signal for at least an additional 20 ms, and then completes the NodeResume operation by issuing the End Of Packet (EOP) sequence. To successfully detect the EOP, software must enter the USB NodeOperational state by setting the NFSR register. If no EOP is received from the host within 100 ms, software must re-initiate NodeResume. NodeReset When detecting a NodeResume or NodeReset signal while in NodeSuspend state, the USB node can signal this to the CPU by generating an interrupt. USB specifications require that a device must be ready to respond to USB tokens within 10 ms after wake-up or reset. 75 www.national.com CP3BT10 16.0 USB Controller CP3BT10 16.2 ENDPOINT OPERATION 16.2.2 Transmit and Receive Endpoint FIFOs The USB node uses a total of seven transmit and receive FIFOs: one bidirectional transmit and receive FIFO for the Packets are broadcast from the host controller to all nodes mandatory control endpoint, three transmit FIFOs, and on the USB network. Address detection is implemented in three receive FIFOs. As shown in Table 36, the bidirectional hardware to allow selective reception of packets and to per- FIFO for the control endpoint is 8 bytes deep. The additional mit optimal use of CPU bandwidth. One function address unidirectional FIFOs are 64 bytes each for both transmit and with seven different endpoint combinations is decoded in receive. Each FIFO can be programmed for one exclusive parallel. If a match is found, then that particular packet is re- USB endpoint, used together with one globally decoded ceived into the FIFO; otherwise it is ignored. USB function address. Software must not enable both transThe incoming USB Packet Address field and Endpoint field mit and receive FIFOs for endpoint zero at any given time. are extracted from the incoming bit stream. Then the adTable 36 Endpoint FIFO Sizes dress field is compared to the Function Address register (FADR). If a match is detected, the Endpoint field is comTX FIFO RX FIFO pared to all of the Endpoint Control registers (EPCn) in parEndpoint allel. A match then causes the payload data to be received Size Size Number Name Name or transmitted using the respective endpoint FIFO. (Bytes) (Bytes) 16.2.1 Address Detection 0 FIFO0 (bidirectional, 8 bytes) USB Packet ADDR Field FADR Register Endpoint Field 1 64 TXFIFO1 - - 2 - - 64 RXFIFO1 3 64 TXFIFO2 - - 4 - - 64 RXFIFO2 5 64 TXFIFO3 - - 6 - - 64 RXFIFO3 Match Match Receive/ Transmit FIFO0 EPC0 Register Transmit FIFO1 If two endpoints in the same direction are programmed with the same endpoint number and both are enabled, data is received or transmitted to/from the endpoint with the lower number, until that endpoint is disabled for bulk or interrupt transfers, or becomes full or empty for ISO transfers. For example, if receive EP2 and receive EP4 both use endpoint 5 and are both isochronous, the first OUT packet is received into EP2 and the second OUT packet into EP4, assuming no software interaction in between. For ISO endpoints, this allows implementing a ping-pong buffer scheme together with the frame number match logic. EPC1 Register Receive FIFO1 EPC2 Register Transmit FIFO2 EPC3 Register Receive FIFO2 EPC4Register Endpoints in different directions programmed with the same endpoint number operate independently. Transmit FIFO3 EPC5 Register Receive FIFO3 EPC6 Register Figure 25. DS049 USB Function Address/Endpoint Decoding www.national.com 76 FIFO0 should be used for the bidirectional control endpoint 0. It can be configured to receive data sent to the default address with the DEF bit in the EPC0 register. Isochronous transfers are not supported for the control endpoint. The Endpoint 0 FIFO can hold a single receive or transmit packet with up to 8 bytes of data. Figure 26 shows the basic operation in both receive and transmit direction. Transmit Endpoint FIFO Operation (TXFIFO1, TXFIFO2, TXFIFO3) The Transmit FIFOs for endpoints 1, 3, and 5 support bulk, interrupt, and isochronous USB packet transfers larger than the actual FIFO size. Therefore, software must update the FIFO contents while the USB packet is transmitted on the bus. Figure 27 illustrates the operation of the transmit FIFOs. Note: The actual current operating state is not directly visible to software. FLUSH Bit, TXC0 Register FLUSH (Resets TXRP and TXWP) FLUSH Bit, RXC0 Register TXRP TFnS - 1 0X0 + IDLE Write to TXD0 TXFL = TXWP - TXRP + RX_EN Bit, RXC0 Register TXWP TX FIFO n TXFILL + RXWAIT SETUP Token TX_EN Bit, TXC0 Register TX_EN Bit, TXC0 Register (Zero-Length Packet) TXWAIT OUT or SETUP Token TCOUNT = TXRP - TXWP (= TFnS - TXFL) DS051 Transmission Done Figure 27. Transmit FIFO Operation FIFO0 Empty (All Data Read) IN Token TFnS TXRP RX TX DS050 Figure 26. Endpoint 0 Operation A packet written to the FIFO is transmitted if an IN token for the respective endpoint is received. If an error condition is detected, the packet data remains in the FIFO and transmission is retried with the next IN token. TXWP The FIFO contents can be flushed to allow response to an OUT token or to write new data into the FIFO for the next IN token. If an OUT token is received for the FIFO, software is informed that the FIFO has received data only if there was no error condition (CRC or STUFF error). Erroneous receptions are automatically discarded. TXFL TCOUNT 77 The Transmit FIFO n Size is the total number of bytes available within the FIFO. The Transmit Read Pointer is incremented every time the Endpoint Controller reads from the transmit FIFO. This pointer wraps around to zero if TFnS is reached. TXRP is never incremented beyond the value of the write pointer TXWP. An underrun condition occurs if TXRP equals TXWP and an attempt is made to transmit more bytes when the LAST bit in the TXCMDx register is not set. The Transmit Write Pointer is incremented every time software writes to the transmit FIFO. This pointer wraps around to zero if TFnS is reached. If an attempt is made to write more bytes to the FIFO than actual space available (FIFO overrun), the write to the FIFO is ignored. If so, TCOUNT is checked for an indication of the number of empty bytes remaining. The Transmit FIFO Level indicates how many bytes are currently in the FIFO. A FIFO warning is issued if TXFL decreases to a specific value. The respective WARNn bit in the FWR register is set if TXFL is equal to or less than the number specified by the TFWL bit in the TXCn register. The Transmit FIFO Count indicates how many empty bytes can be filled within the transmit FIFO. This value is accessible by software in the TXSn register. www.national.com CP3BT10 Bidirectional Control Endpoint FIFO0 Operation CP3BT10 16.3 Receive Endpoint FIFO Operation (RXFIFO1, RXFIFO2, RXFIFO3) The Receive FIFOs for endpoints 2, 4, and 6 support bulk, interrupt, and isochronous USB packet transfers larger than the actual FIFO size. If the packet length exceeds the FIFO size, software must read the FIFO contents while the USB packet is being received on the bus. Figure 28 shows the detailed behavior of receive FIFOs. USB CONTROLLER REGISTERS The USB node has a set of memory-mapped registers that can be read/written from the CPU bus to control the USB interface. Some register bits are reserved; reading from these bits returns undefined data. Reserved register bits must always be written with 0. Table 37 USB Controller Registers Name Address Description MCNTRL FF FD80h Main Control Register NFSR FF FD8Ah Node Functional State Register MAEV FF FD8Ch Main Event Register ALTEV FF FD90h Alternate Event Register MAMSK FF FD8Eh Main Mask Register ALTMSK FF FD92h Alternate Mask Register TXEV FF FD94h Transmit Event Register TXMSK FF FD96h Transmit Mask Register RXEV FF FD98h Receive Event Register RXMSK FF FD9Ah Receive Mask Register NAKEV FF FD9Ch NAK Event Register NAKMSK FF FD9Eh NAK Mask Register FWEV FF FDA0h FIFO Warning Event Register FWMSK FF FDA2h FIFO Warning Mask Register FNH FF FDA4h Frame Number High Byte Register FNL FF FDA6h Frame Number Low Byte Register FAR FF FD88h Function Address Register DMACNTRL FF FDA8h DMA Control Register DMAEV FF FDAAh DMA Event Register DMAMSK FF FDACh DMA Mask Register MIR FF FDAEh Mirror Register DMACNT FF FDB0h DMA Count Register DMAERR FF FDB2h DMA Error Register FLUSH (Resets RXRP and RXWP) RXRP RFnS - 1 0X0 + RCOUNT = RXWP - RXRF + RXWP RX FIFO n + RXFL = RXRP - RXWP (= RFnS - RCOUNT) DS052 Figure 28. Receive FIFO Operation RFnS RXRP RXWP RXFL RCOUNT The Receive FIFO n Size is the total number of bytes available within the FIFO. The Receive Read Pointer is incremented with every read by software from the receive FIFO. This pointer wraps around to zero if RFnS is reached. RXRP is never incremented beyond the value of RXWP. If an attempt is made to read more bytes than are actually available (FIFO underrun), the last byte is read repeatedly. The Receive Write Pointer is incremented every time the Endpoint Controller writes to the receive FIFO. This pointer wraps around to zero if RFnS is reached. An overrun condition occurs if RXRP equals RXWP and an attempt is made to write an additional byte. The Receive FIFO Level indicates how many more bytes can be received until an overrun condition occurs with the next write to the FIFO. A FIFO warning is issued if RXFL decreases to a specific value. The respective WARNn bit in the FWR register is set if RXFL is equal to or less than the number specified by the RFWL bit in the RXCn register. The Receive FIFO Count indicates how many bytes can be read from the receive FIFO. This value is accessible by software from the RXSn register. www.national.com 78 Name Address Description Name Address Description EPC0 FF FDC0h Endpoint Control 0 Register RXS3 FF FDFCh Receive Status 3 Register EPC1 FF FDD0h Endpoint Control 1 Register RXC0 FF FDCEh Receive Command 0 Register EPC2 FF FDD8h Endpoint Control 2 Register RXC1 FF FDDEh Receive Command 1 Register EPC3 FF FDE0h Endpoint Control 3 Register RXC2 FF FDEEh Receive Command 2 Register EPC4 FF FDDE8h Endpoint Control 4 Register RXC3 FF FDFEh Receive Command 3 Register EPC5 FF FDF0h Endpoint Control 5 Register RXD0 FF FDCAh Receive Data 0 Register EPC6 FF FDF8h Endpoint Control 6 Register RXD1 FF FDDAh Receive Data 2 Register TXS0 FF FDC4h Transmit Status 0 Register RXD2 FF FDEAh Receive Data 2 Register TXS1 FF FDD4h Transmit Status 1 Register RXD3 FF FDFAh Receive Data 3 Register TXS2 FF FDE4h Transmit Status 2 Register 16.3.1 The MCNTRL register controls the main functions of the USB node. The MCNTRL register provides read/write access from the CPU bus. Reserved bits must be written with 0, and they return 0 when read. It is clear after reset. TXS3 FF FDF4h Transmit Status 3 Register TXC0 FF FDC6h Transmit Command 0 Register TXC1 FF FDD6 Transmit Command 1 Register TXC2 FF FDE6h Transmit Command 2 Register TXC3 FF FDF6h Transmit Command 3 Register TXD0 FF FDC2h Transmit Data 0 Register TXD1 FF FDD2h Transmit Data 1 Register TXD2 FF FDE2h Transmit Data 2 Register TXD3 FF FDF2h Transmit Data 3 Register RXS0 FF FDCCh Receive Status 0 Register RXS1 FF FDDCh Receive Status 1 Register RXS2 FF FDECh Receive Status 2 Register Main Control Register (MCNTRL) 7 4 Reserved USBEN 79 3 NAT 2 1 Reserved 0 USBEN The USB Enable controls whether the USB module is enabled. If the USB module is disabled, the 48 MHz clock within the USB node is stopped, all USB registers are initialized to their reset state, and the USB transceiver forces SE0 on the bus to prevent the hub from detected the USB node. The USBEN bit is clear after reset. 0 – The USB module is disabled. 1 – The USB module is enabled. www.national.com CP3BT10 Table 37 USB Controller Registers Table 37 USB Controller Registers CP3BT10 NAT The Node Attached indicates that this node is ready to be detected as attached to USB. When clear, the transceiver forces SE0 on the USB node controller to prevent the hub (to which this node is connected) from detecting an attach event. After reset or when the USB node is disabled, this bit is cleared to give the device time before it must respond to commands. After this bit has been set, the device no longer drives the USB and should be ready to receive Reset signaling from the hub. 0 – Node not ready to be detected as attached. 1 – Node ready to be detected as attached. 16.3.2 Node Functional State Register (NFSR) The NFSR register reports and controls the current functional state of the USB node. The NFSR register provides read/write access. It is clear after reset. 7 2 Reserved NFS 1 0 NFS The Node Functional State bits set the node state, as shown in Table 38. Software should initiate all required state transitions according to the respective status bits in the Alternate Event (ALTEV) register. Table 38 USB Functional States NFS Node State Description 00 NodeReset This is the USB Reset state. This is entered upon a module reset or by software upon detection of a USB Reset. Upon entry, all endpoint pipes are disabled. DEF in the Endpoint Control 0 (EPC0) register and AD_EN in the Function Address (FAR) register should be cleared by software on entry to this state. On exit, DEF should be reset so the device responds to the default address. 01 NodeResume In this state, resume “K” signalling is generated. This state should be entered by software to initiate a remote wake-up sequence by the device. The node must remain in this state for at least 1 ms and no more than 15 ms. 10 11 NodeOperational This is the normal operational state for operation on the USB bus. NodeSuspend www.national.com Suspend state should be entered by software on detection of a Suspend event while in Operational state. While in Suspend state, the transceivers operate in their low-power suspend mode. All endpoint controllers and the bits TX_EN, LAST, and RX_EN are reset, while all other internal states are frozen. On detection of bus activity, the RESUME bit in the ALTEV register is set. In response, software can cause entry to NodeOperational state. 80 Main Event Register (MAEV) RX_EV The Receive Event bit is set if any of the unmasked bits in the Receive Event (RXEV) register is set. It indicates that a SETUP or OUT transaction has been completed. This bit is cleared when all of the RX_LAST bits in each Receive Status (RXSn) register and all RXOVRRN bits in the RXEV register are cleared. 0 – No receive event has occurred. 1 – A receive event has occurred. The Master Interrupt Enable bit is hardwired to 0 in the Main Event (MAEV) register; bit 7 in the Main Mask (MAMSK) register is the Master Interrupt Enable. 0 – USB interrupts disabled. 1 – USB interrupts enabled. The Main Event Register summarizes and reports the main events of the USB transactions. This register provides readonly access. The MAEV register is clear after reset. 7 6 5 4 3 2 1 0 INTR RX_EV ULD NAK FRAME TX_EV ALT WARN INTR WARN ALT TX_EV FRAME NAK UL The Warning Event bit indicates whether one of the unmasked bits in the FIFO Warning Event (FWEV) register has been set. This bit is cleared by reading the FWEV register. 0 – No warning event occurred. 1 – A warning event has occurred. The Alternate Event bit indicates whether one of the unmasked ALTEV register bits has been set. This bit is cleared by reading the ALTEV register. 0 – No alternate event has occurred. 1 – An alternate event has occurred. The Transmit Event bit indicates whether any of the unmasked bits in the Transmit Event (TXEV) register (TXFIFOn or TXUNDRNn) is set. Therefore, it indicates that an IN transaction has been completed. This bit is cleared when all the TX_DONE bits and the TXUNDRN bits in each Transmit Status (TXSn) register are cleared. 0 – No transmit event has occurred. 1 – A transmit event has occurred. The Frame Event bit indicates whether the frame counter has been updated with a new value, due to receipt of a valid SOF packet on the USB or to an artificial update if the frame counter was unlocked or a frame was missed. This bit is cleared when the register is read. 0 – The frame counter has not been updated. 1 – Frame counter has been updated. The Negative Acknowledge Event indicates whether one of the unmasked NAK Event (NAKEV) register bits has been set. This bit is cleared when the NAKEV register is read. 0 – No unmasked NAK event has occurred. 1 – An unmasked NAK event has occurred. The Unlocked/Locked Detected bit is set when the frame timer has either entered unlocked condition from a locked condition, or has re-entered a locked condition from an unlocked condition as determined by the UL bit in the Frame Number (FNH or FNL) register. This bit is cleared when the register is read. 0 – Frame timer has not entered an unlocked condition from a locked condition or reentered a locked condition from an unlocked condition. 1 – Frame timer has either entered an unlocked condition from a locked condition or re-entered a locked condition from an unlocked condition. 16.3.4 Main Mask Register (MAMSK) The MAMSK register masks out events reported in the MAEV registers. A set bit enables the interrupts for the respective event in the MAEV register. If the corresponding bit is clear, interrupt generation for this event is disabled. This register provides read/write access. The MAMSK register is clear after reset. 7 6 5 4 3 2 1 0 INTR RX_EV ULD NAK FRAME TX_EV ALT WARN 16.3.5 Alternate Event Register (ALTEV) The ALTEV register summarizes and reports the further events in the USB node. This register provides read-only access. The ALTEV register is clear after reset. 7 6 5 RESUME RESET SD5 DMA EOP 81 4 3 2 1 0 SD3 EOP DMA Reserved The DMA Event bit indicates that one of the unmasked bits in the DMA Event (DMAEV) register has been set. The DMA bit is readonly and clear, when the DMAEV register is cleared. 0 – No DMA event has occurred. 1 – A DMA event has occurred. The End of Packet bit indicates whether a valid EOP sequence has been detected on the USB. It is used when this device has initiated a Remote wake-up sequence to indicate that the Resume sequence has been acknowledged and completed by the host. This bit is cleared when the register is read. 0 – No EOP sequence detected. 1 – EOP sequence detected. www.national.com CP3BT10 16.3.3 CP3BT10 SD3 SD5 RESET RESUME 16.3.6 The Suspend Detect 3 ms bit is set after 3 ms of IDLE have been detected on the upstream port, indicating that the device should be suspended. The suspend occurs under software control by writing the suspend value to the Node Functional State (NFSR) register. This bit is cleared when the register is read. 0 – No 3 ms in IDLE has been detected. 1 – 3 ms in IDLE has been detected. The Suspend Detect 5 ms bit is set after 5 ms of IDLE have been detected on the upstream port, indicating that this device is permitted to perform a remote wake-up operation. The resume may be initiated under software control by writing the resume value to the NFSR register. This bit is cleared when the register is read. 0 – No 5 ms in IDLE has been detected. 1 – 5 ms in IDLE has been detected. The Reset bit is set when 2.5 µs of SEO have been detected on the upstream port. In response, the functional state should be reset (NFS in the NFSR register is set to RESET), where it must remain for at least 100 µs. The functional state can then return to Operational state. This bit is cleared when the register is read. 0 – No 2.5 µs in SEO have been detected. 1 – 2.5 µs in SEO have been detected. The Resume bit indicates whether resume signalling has been detected on the USB when the device is in Suspend state (NFS in the NFSR register is set to SUSPEND), and a non-IDLE signal is present on the USB, indicating that this device should begin its wakeup sequence and enter Operational state. Resume signalling can only be detected when the 48 MHz PLL clock is enabled to the USB controller. This bit is cleared when the register is read. 0 – No resume signalling detected. 1 – Resume signalling detected. Alternate Mask Register (ALTMSK) A set bit in the ALTMSK register enables automatic setting of the ALT bit in the MAEV register when the respective event in the ALTEV register occurs. Otherwise, setting MAEV.ALT bit is disabled. The ALTMSK register is clear after reset. It provides read/write access from the CPU bus. 7 6 5 RESUME RESET SD5 www.national.com 4 3 2 1 0 SD3 EOP DMA Reserved 82 16.3.7 Transmit Event Register (TXEV) The TXEV register reports the current status of the FIFOs, used by the three Transmit Endpoints. The TXEV register is clear after reset. It provides read-only access. 7 4 3 TXUDRRN TXFIFO TXUDRRN 16.3.8 0 TXFIFO The Transmit FIFO n bits are copies of the TX_DONE bits from the corresponding Transmit Status registers (TXSn). A bit is set when the IN transaction for the corresponding transmit endpoint n has been completed. These bits are cleared when the corresponding TXSn register is read. The Transmit Underrun n bits are copies of the respective TX_URUN bits from the corresponding Transmit Status registers (TXSn). Whenever any of the Transmit FIFOs underflows, the respective TXUDRRN bit is set. These bits are cleared when the corresponding Transmit Status register is read. Note: Since Endpoint 0 implements a store and forward principle, an underrun condition for FIFO0 cannot occur. This results in the TXUDRRN0 bit always being read as 0. Transmit Mask Register (TXMSK) The TXMSK register is used to select the bits of the TXEV registers, which causes the TX_EV bit in the MAEV register to be set. When a bit is set and the corresponding bit in the TXEV register is set, the TX_EV bit in the MAEV register is set. When clear, the corresponding bit in the TXEV register does not cause TX_EV to be set. The TXMSK register provides read/write access. It is clear after reset. 7 4 TXUDRRN 3 0 TXFIFO Receive Event Register (RXEV) 16.3.11 NAK Event Register (NAKEV) The RXEV register reports the current status of the FIFO, used by the three Receive Endpoints. The RXEV register is clear after reset. It provides read-only access from the CPU bus. 7 4 3 RXOVRRN RXFIFO RXOVRRN A bit in the NAKEV register is set when a Negative Acknowledge (NAK) was generated by the corresponding endpoint. The NAKEV register provides read-only access from the CPU bus. It is clear after reset. 0 7 RXFIFO 4 3 OUT The Receive FIFO n are set whenever either RX_ERR or RX_LAST in the respective Receive Status registers (RXSn) are set. Reading the corresponding RXSn register automatically clears these bits. The USB node discards all packets for Endpoint 0 received with errors. This is necessary in case of retransmission due to media errors, ensuring that a good copy of a SETUP packet is captured. Otherwise, the FIFO may potentially be tied up, holding corrupted data and unable to receive a retransmission of the same packet (the RXFIFO0 bit only reflects the value of RX_LAST for Endpoint 0). If data streaming is used for the receive endpoints (EP2, EP4 and EP6), software must check the respective RX_ERR bits to ensure the packets received are not corrupted by errors. The Receive Overrun n bits are set when an overrun condition is indicated in the corresponding receive FIFO n. They are cleared when the register is read. Software must check the respective RX_ERR bits that packets received for the other receive endpoints (EP2, EP4 and EP6) are not corrupted by errors, as these endpoints support data streaming (packets which are longer than the actual FIFO depth). IN OUT 0 IN The IN n bits are set when a NAK handshake is generated for an enabled address/endpoint combination (AD_EN in the Function Address, FAR, register is set and EP_EN in the Endpoint Control, EPCx, register is set) in response to an IN token. These bits are cleared when the register is read. The OUT n bits are set when a NAK handshake is generated for an enabled address/ endpoint combination (AD_EN in the FAR register is set and EP_EN in the EPCx register is set) in response to an OUT token. These bits are not set if NAK is generated as result of an overrun condition. They are cleared when the register is read. 16.3.12 NAK Mask Register (NAKMSK) The NAKMSK register is used to select the bits of the NAKEV register, which cause the NAK bit in the MAEV register to be set. When set and the corresponding bit in the NAKEV register is set, the NAK bit in the MAEV register is set. When cleared, the corresponding bit in the NAKEV register does not cause NAK to be set. The NAKMSK register provides read/write access. It is clear after reset. 7 4 OUT 3 0 IN 16.3.10 Receive Mask Register (RXMSK) The RXMSK register is used to select the bits of the RXEV register, which cause the RX_EV bit in the MAEV register to be set. When set and the corresponding bit in the RXEV register is set, RX_EV bit in the MAEV register is set. When clear, the corresponding bit in the RXEV register does not cause the RX_EV bit to be set. The RXMSK register provides read/write access. This register is clear after reset. 7 4 RXOVRRN 3 0 RXFIFO 83 www.national.com CP3BT10 16.3.9 CP3BT10 16.3.13 FIFO Warning Event Register (FWEV) 16.3.15 Frame Number High Byte Register (FNH) The FWEV register signals whether a receive or transmit FIFO has reached its warning limit. It reports the status for all FIFOs, except for the Endpoint 0 FIFO, as no warning limit can be specified for this FIFO. The FWEV register provides read-only access from the CPU bus. It is clear after reset. The FNH register contains the three most significant bits (MSB) of the current frame counter as well as status and control bits for the frame counter. This register is loaded with C0h after reset. It provides access from the CPU bus as described below. 7 5 RXWARN3:1 4 3 Res. 1 TXWARN3:1 0 7 6 5 MF UL RFC FN10:8 The Transmit Warning n bits are set when the respective transmit endpoint FIFO reaches the warning limit, as specified by the TFWL bits of the respective TXCn register, and transmission from the respective endpoint is enabled. These bits are cleared when the warning condition is cleared by either writing new data to the FIFO when the FIFO is flushed, or when transmission is done, as indicated by the TX_DONE bit in the TXSn register. RXWARN3:1 The Receive Warning n bits are set when the respective receive endpoint FIFO reaches the warning limit, as specified by the RFWL bits of the respective EPCx register. These bits are cleared when the warning condition is cleared by either reading data from the FIFO or when the FIFO is flushed. 16.3.14 FIFO Warning Mask Register (FWMSK) The FWMSK register selects which FWEV bits are reported in the MAEV register. A set FWMSK bit with the corresponding bit in the FWEV register set, causes the WARN bit in the RFC MAEV register to be set. When clear, the corresponding bit in the FWEV register does not cause WARN to be set. The FWMSK register provides read/write access. This register is clear after reset. 5 RXWARN3:1 4 Res. 3 1 TXWARN3:1 0 Res. UL www.national.com 3 2 0 FN10:8 Res. TXWARN3:1 7 4 Reserved 84 The Frame Number field holds the three most significant bits (MSB) of the current frame number, received in the last SOF packet. If a valid frame number is not received within 12060 bit times (Frame Length Maximum, FLMAX, with tolerance) of the previous change, the frame number is incremented artificially. If two successive frames are missed or are incorrect, the current FN is frozen and loaded with the next frame number from a valid SOF packet. If the frame number low byte was read by software before reading the FNH register, software actually reads the contents of a buffer register which holds the value of the three frame number bits of this register when the low byte was read. Therefore, the correct sequence to read the frame number is: FNL, FNH. Read operations to the FNH register, without first reading the Frame Number Low Byte (FNL) register directly, read the actual value of the three MSBs of the frame number. The FN bits provide read-only access. On reset, the FN bits are cleared. The Reset Frame Count bit is used to reset the frame number to 000h. This bit always reads as 0. Due to the synchronization elements the frame counter reset actually occurs a maximum of 3 USB clock cycles (12 MHz) plus 2.5 CPU clock cycles after the write to the RFC bit. 0 – Writing 0 has no effect. 1 – Writing 1 resets the frame counter. The Unlock Flag bit indicates that at least two frames were received without an expected frame number, or that no valid SOF was received within 12060 bit times. If this bit is set, the frame number from the next valid SOF packet is loaded in FN. The UL bit provides read-only access. After reset, this bit is set. This bit is set by the hardware and is cleared by reading the FNH register. 0 – No condition indicated. 1 – At least two frames were received without an expected frame number, or no valid SOF was received within 12060 bit times. The Missed SOF bit is set when the frame number in a valid received SOF does not match the expected next value, or when an SOF is not received within 12060 bit times. The MF bit provides read-only access. On reset, this bit is set. This bit is set by the hardware and is cleared by reading the FNH register. 0 – No condition indicated. 1 – The frame number in a valid SOF does not match the expected next value, or no valid SOF was received within 12060 bit times. 16.3.18 Control Register (DMACNTRL) The DMACNTRL register controls the main DMA functions of the USB node. The DMACTRL register provides read/ write access. This register is clear after reset. 7 6 DEN IGNRXTGL DSRC 16.3.16 Frame Number Low Byte Register (FNL) The FNL register holds the low byte of the frame number, as described above. To ensure consistency, reading this low byte causes the three frame number bits in the FNH register to be locked until this register is read. The correct sequence to read the frame number is: FNL first, followed by FNH. This register provides read-only access. After reset, the FNL register is clear. 7 FN7:0 DMOD 16.3.17 Function Address Register (FAR) The Function Address Register specifies the device function address. The different endpoint numbers are set for each endpoint individually using the Endpoint Control registers. The FAR register provides read/write access. After reset, this register is clear. If the DEF bit in the Endpoint Control 0 register is set, Endpoint 0 responds to the default address. 7 AD_EN AD AD_EN 6 4 3 DTGL ADMA DMOD 2 0 DSRC The DMA Source bit field holds the binary-encoded value that specifies which of the endpoints, 1 to 6, is enabled for DMA support. The DSRC bits are cleared on reset. Table 39 summarizes the DSRC bit settings. Table 39 DSRC Bit Description 0 Note: If the frame counter is updated due to a receipt of a valid SOF or an artificial update (i.e. missed frame or unlocked/locked detect), it will take the synchronization elements a maximum of 2.5 CPU clock cycles to update the FNH and FNL registers. 5 0 AD The Address field holds the 7-bit function ad- ADMA dress used to transmit and receive all tokens addressed to this device. The Address Enable bit controls whether the AD field is used for address comparison. If not, the device does not respond to any token on the USB bus. 0 – The device does not respond to any token on the USB bus. 1 – The AD field is used for address comparison. 85 DSRC Endpoint Number 000 1 001 2 010 3 011 4 100 5 101 6 11x Reserved The DMA Mode bit specifies when a DMA request is issued. If clear, a DMA request is issued on transfer completion. For transmit endpoints EP1, EP3, and EP5, the data is completely transferred, as indicated by the TX_DONE bit (to fill the FIFO with new transmit data). For receive endpoints EP2, EP4, and EP6, this is indicated by the RX_LAST bit. When the DMOD bit is set, a DMA request is issued when the respective FIFO warning bit is set. The DMOD bit is cleared after reset. 0 – DMA request is issued on transfer completion. 1 – DMA request is issued when the respective FIFO warning bit is set. The Automatic DMA bit enables Automatic DMA (ADMA) and automatically enables the selected receive or transmit endpoint. Before ADMA mode can be enabled, the DEN bit in the DMA Control (DMACNTRL) register must be cleared. ADMA mode functions until any bit in the DMA Event (DMAEV) register is set, except for NTGL. To initiate ADMA mode, all bits in the DMAEV register must be cleared, except for NTGL. 0 – Automatic DMA disabled. 1 – Automatic DMA enabled. www.national.com CP3BT10 MF CP3BT10 DTGL The DMA Toggle bit is used to determine the initial state of Automatic DMA (ADMA) operations. Software initially sets this bit if starting with a DATA1 operation, and clears this bit if starting with a DATA0 operation. Writes to this bit also update the NTGL bit in the DMAEV register. IGNRXTGL The Ignore RX Toggle controls whether the compare between the NTGL bit in the DMAEV register and the TOGGLE bit in the respective RXSn register is ignored during receive operations. If the compare is ignored, a mismatch DCNT of the bits during a receive operation does not stop ADMA operation. If the compare is not ignored, the ADMA stops in case of a mismatch of the two toggle bits. After reset, this bit is cleared. 0 – Compare toggle bits. 1 – Ignore toggle bits. DEN The DMA Enable bit enables DMA mode. If DSIZ DMA mode is disabled and the current DMA cycle has been completed (or was not yet issued) the DMA transfer is terminated. This bit is cleared after reset. 0 – DMA mode disabled. 1 – DMA mode enabled. 16.3.19 DMA Event Register (DMAEV) The DMAEV register bits are used in ADMA mode. Bits 0 to 3 may cause an interrupt if not cleared, even if the device is not set to ADMA mode. Until all of these bits are cleared, ARDY ADMA mode cannot be initiated. Conversely, ADMA mode is automatically terminated when any of these bits are set. The DMAEV register provides access from the CPU bus as described below. It is clear after reset. 7 6 Reserved DSHLT DERR 5 4 3 2 1 0 NTGL ARDY DSIZ DCNT DERR DSHLT The DMA Software Halt bit is set when ADMA operations have been halted by software. This NTGL bit is set by the hardware only after the DMA engine completes any necessary cleanup operations and returns to Idle state. The DSHLST bits provide read access and can only be written with a 0 from the CPU bus. After reset these bits are cleared. 0 – No software ADMA halt. 1 – ADMA operations have been halted by software. The DMA Error bit is set to indicate that a packet has not been received or transmitted correctly. It is also set, if the TOGGLE bit in the RXSx/TXSx register does not equal the NTGL bit in the DMAEV register after packet reception/transmission. (Note that this comparison is made before the NTGL bit changes state due to packet transfer). For receiving, the DERR bit is equivalent to the RX_ERR bit. For transmitting, the DERR bit is equivalent to the www.national.com 86 TX_DONE bit (set) and the ACK_STAT bit (not set). If the AEH bit in the DMA Error Count (DMAERR) register is set, the DERR bit is not set until DMAERRCNT in the DMAERR register is cleared, and another error is detected. Errors are handled as specified in the DMAERR register. The DERR bit provides read access and can only be written with a 0 from the CPU bus. After reset this bit is cleared. 0 – No DMA error occurred. 1 – DMA error occurred. The DMA Count bit is set when the DMA Count (DMACNT) register is 0 (see the DMACNT register for more information). The DCNT bit provides read access and can only be written with a 0 from the CPU bus. After reset this bit is cleared. 0 – DMACNT register is not 0. 1 – DMACNT register is 0. The DMA Size bit is only significant for DMA receive operations. It indicates, by being set, that a packet has been received which is less than the full length of the FIFO. This normally indicates the end of a multi-packet transfer. The DSIZ bit provides read access and can only be written with a 0 from the CPU bus. After reset this bit is cleared. 0 – No condition indicated. 1 – A packet has been received which is less than the full length of the FIFO. The Automatic DMA Ready bit is set when the ADMA mode is ready and active. After setting the DMACNTRL.ADMA bit and the active USB transaction (if any) is finished and the specified endpoint (DMACNTRL.DSRC) is flushed, the USB node enters ADMA mode. This bit is automatically cleared when the ADMA mode is finished and the current DMA operation is completed. After reset the ARDY bit is cleared. 0 – ADMA mode not ready. 1 – ADMA mode ready and active. The Next Toggle bit determines the toggle state of the next data packet sent (if transmitting), or the expected toggle state of the next data packet (if receiving). This bit is initialized by writing to the DTGL bit of the DMACNTRL register. It then changes state with every packet sent or received on the endpoint presently selected by DSRC[2:0]. If DTGL write operation occurs simultaneously with the bit update operation, the write takes precedence. If transmitting, whenever ADMA operations are in progress the DTGL bit overrides the corresponding TOGGLE bit in the TXCx register. In this way, the alternating data toggle occurs correctly on the USB. Note that there is no corresponding mask bit for this event because it is not used to generate interrupts. The NTGL bit provides read-only access from the CPU bus and is cleared after reset. 16.3.23 DMA Error Register (DMAERR) Any set bit in the DMAMSK register enables automatic setting of the DMA bit in the ALTEV register when the respective event in the DMAEV register occurs. Otherwise, setting the DMA bit is disabled. For a description of bits 0 to 3, see the DMAEV register. The DMAMSK register provides read/ write access. After reset it is clear. Reading reserved bits returns undefined data. The DMAERR register holds the 7-bit DMA error counter and a control bit to specify DMA error handling. The DMAERR register provides read/write access. It is clear after reset. 7 AEH 7 4 Reserved 3 2 1 16.3.21 Mirror Register (MIR) The MIR register is a read-only register. Because reading it does not alter the state of the TXSn or RXSn register to which it points, software can freely check the status of the channel. At reset it is initialized to 1Fh. 0 STAT STAT The Status field mirrors the status bits of the transmitter or receiver n selected by the DSRC[2:0] field in the DMACNTRL register (DMA need not be active or enabled). It corresponds to TXSn or RXSn, respectively. 16.3.22 DMA Count Register (DMACNT) The DMACNT register specifies a maximum count for ADMA operations. The DMACNT register provides read/ write access. After reset this register is clear. 7 0 DCOUNT DCOUNT 0 DMAERRCNT 0 DSIZ DCNT DERR DSHLT 7 6 The DMA Count field is decremented on completion of a DMA operation until it reaches 0. Then the DCNT bit in the DMA Event register is set, only when the next successful DMA operation is completed. This register does not underflow. For receive operations, this count decrements when the packet is received successfully, and then transferred to memory using DMA. For transmit operations, this count decrements when the packet is transferred from memory using DMA, and then transmitted successfully. Software loads DCOUNT with (number of packets to transfer) - 1. If a DMACNT write operation occurs simultaneously with the decrement operation, the write takes precedence. DMAERRCNT The DMA Error Counter, together with the automatic error handling feature, defines the maximum number of consecutive bus errors before ADMA mode is stopped. Software can set the 7-bit counter to a preset value. Once ADMA is started, the counter decrements from the preset value by 1 every time a bus error is detected. Every successful transaction resets the counter back to the preset value. When ADMA mode is stopped, the counter is also set back to the preset value. If the counter reaches 0 and another erroneous packet is detected, the DERR bit in the DMA Event register is set. This register cannot underrun. Software loads DMAERRCNT with 3D (maximum number of allowable transfer attempts) - 1. A write access to this register is only possible when ADMA is inactive. Otherwise, it is ignored. Reading from this register while ADMA is active returns the current counter value. Reading from it while ADMA is inactive returns the preset value. The counter decrements only if the AEH bit is set (automatic error handling activated). AEH The Automatic Error Handling bit has two different meanings, depending on the current mode: Non-Isochronous mode—This mode is used for bulk, interrupt and control transfers. Setting AEH in this mode enables automatic handling of packets containing CRC or bit-stuffing errors. If this bit is set during transmit operations, the USB node automatically reloads the FIFO and reschedules the packet to which the host did not return an ACK. If this bit is clear, automatic error handling ceases. If this bit is set during receive operations, a packet received with an error (as specified in the DERR bit description in the DMAEV register) is automatically flushed from the FIFO being used so that the packet can be received again. If this bit is cleared, automatic error handling ceases. Isochronous mode—Setting this bit allows the USB node to ignore packets received with errors (as specified in the DERR bit description in the DMAMSK register). If this bit is set during receive operations, the USB node is automatically flushed and the receive FIFO is reset to 87 www.national.com CP3BT10 16.3.20 DMA Mask Register (DMAMSK) CP3BT10 receive the next packet. The erroneous packet is ignored and not transferred via DMA. If this bit is cleared, automatic error handling ceases. 16.3.25 Transmit Status 0 Register (TXS0) The TXS0 register reports the transmit status of the mandatory Endpoint 0. It is loaded with 08h after reset. This register allows read-only access from the CPU bus. 16.3.24 Endpoint Control 0 Register (EPC0) The EPC0 register controls the mandatory Endpoint 0. It is clear after reset. Reserved bits read undefined data. 7 6 STALL DEF EP DEF STALL 5 4 Reserved 3 6 5 4 3 Res. ACK_STAT TX_DONE Res. 0 TCOUNT 0 TCOUNT EP The Endpoint Address field holds the 4-bit endpoint address. For Endpoint 0, these bits are hardwired to 0000b. Writing a 1 to any of the EP bits is ignored. The Default Address aids in the transition from the default address to the assigned address. When set, the device responds to the default address without regard to the contents of FAR6-0/EP03-0 fields. When an IN packet is transmitted for the endpoint, the DEF bit is automatically cleared. This bit provides read/ write access from the CPU bus. After reset, this bit is clear. The transition from the default address 00000000000b to an address assigned during bus enumeration may not occur in the middle of the SET_ADDRESS control sequence. This is necessary to complete the control sequence. However, the address must change immediately after this sequence finishes in order to avoid errors when another control sequence immediately follows the SET_ADDRESS command. On USB reset, software has 10 ms for set-up, and should write 80h to the FAR register and 00h to the EPC0 register. On receipt of a SET_ADDRESS command, software must write 40h to the EPC0 register and 80h to the FAR register. It must then queue a zero length IN packet to complete the status phase of the SET_ADDRESS control sequence. 0 – Do not respond to the default address. 1 – Respond to default address. The Stall bit can be used to enable STALL handshakes under the following conditions: The transmit FIFO is enabled and an IN token is received. The receive FIFO is enabled and an OUT token is received. A SETUP token does not cause a STALL handshake to be generated when this bit is set. After transmitting the STALL handshake, the RX_LAST and the TX_DONE bits in the respective Receive/Transmit Status registers are set. This bit allows read/write access from the CPU bus. After reset this bit is cleared. 0 – Disable STALL handshakes. 1 – Enable STALL handshakes. www.national.com 7 88 TX_DONE ACK_STAT The Transmission Count field indicates the number of empty bytes available in the FIFO. This field is never larger than 8 for Endpoint 0. The Transmission Done bit indicates whether a packet has completed transmission. The TX_DONE bit is cleared when this register is read. 0 – No completion of packet transmission has occurred. 1 – A packet has completed transmission. The Acknowledge Status bit indicates the status, as received from the host, of the ACK for the packet previously sent. This bit is to be interpreted when TX_DONE is set. It is set when an ACK is received; otherwise, it remains cleared. This bit is cleared when this register is read. 0 – No ACK received. 1 – ACK received. 16.3.26 Transmit Command 0 Register (TXC0) The TXC0 register controls the mandatory Endpoint 0 when used in transmit direction. This register allows read/write access from the CPU bus. It is clear after reset. Reading reserved bits returns undefined data. 7 5 Reserved TX_EN TOGGLE 4 3 2 1 0 IGN_IN FLUSH TOGGLE Res. TX_EN The Transmission Enable bit enables data transmission from the FIFO. It is cleared by hardware after transmitting a single packet, or a STALL handshake, in response to an IN token. It must be set by software to start packet transmission. The RX_EN bit in the Receive Command 0 (RXC0) register takes precedence over this bit; i.e. if the RX_EN bit is set, the TX_EN bit is ignored until RX_EN is reset. Zero length packets are indicated by setting this bit without writing any data to the FIFO. 0 – Transmission from the FIFO disabled. 1 – Transmission from the FIFO enabled. The Toggle bit specifies the PID used when transmitting the packet. A value of 0 causes a DATA0 PID to be generated, while a value of 1 causes a DATA1 PID to be generated. This bit is not altered by the hardware. 0 – DATA0 PID is used. 1 – DATA1 PID is used. Writing a 1 to the Flush FIFO bit flushes all TOGGLE The Toggle bit reports the PID used when redata from the control endpoint FIFOs, resets ceiving the packet. When clear, this bit indithe endpoint to Idle state, clears the FIFO cates that the last successfully received read and write pointer, and then clears itself. packet had a DATA0 PID. When set, this bit inIf the endpoint is currently using the FIFO0 to dicates that the packet had a DATA1 PID. This transfer data on USB, flushing is delayed until bit is unchanged for zero-length packets. It is after the transfer is complete. The FLUSH bit cleared when this register is read. is cleared on reset. It is equivalent to the 0 – DATA0 PID was used. FLUSH bit in the RXC0 register. 1 – DATA1 PID was used. 0 – Writing 0 has no effect. SETUP The Setup bit indicates that the setup packet 1 – Writing 1 flushed the FIFOs. has been received. This bit is unchanged for IGN_IN When the Ignore IN Tokens bit is set, the endzero-length packets. It is cleared when this point will ignore any IN tokens directed to its register is read. configured address. 0 – Setup packet has not been received. 0 – Do not ignore IN tokens. 1 – Setup packet has been received. 1 – Ignore IN tokens. 16.3.29 Receive Command 0 Register (RXC0) 16.3.27 Transmit Data 0 Register (TXD0) The RXC0 register controls the mandatory Endpoint 0 when Data written to the TXD0 register is copied into the FIFO of used in receive direction. This register provides read/write Endpoint 0 at the current location of the transmit write point- access from the CPU bus. It is clear after reset. er. The register allows write-only access from the CPU bus. 7 7 0 4 Reserved 3 2 1 0 FLUSH IGN_SETUP IGN_OUT RX_EN TXFD RX_EN The Receive Enable bit enables receiving packets. OUT packet reception is disabled after every data packet is received, or when a STALL handshake is returned in response to an OUT token. The RX_EN bit must be set to re-enable data reception. Reception of SET16.3.28 Receive Status 0 Register (RXS0) UP packets is always enabled. In the case of The RXS0 register indicates status conditions for the bidiback-to-back SETUP packets (for a given rectional Control Endpoint 0. To receive a SETUP packet afendpoint) where a valid SETUP packet is reter receiving a zero length OUT/SETUP packet, there are ceived with no other intervening non-SETUP two copies of this register in hardware. One holds the retokens, the Endpoint Controller discards the ceive status of a zero length packet, and another holds the new SETUP packet and returns an ACK handstatus of the next SETUP packet with data. If a zero length shake. If any other reasons prevent the Endpacket is followed by a SETUP packet, the first read of this point Controller from accepting the SETUP register indicates the status of the zero length packet (with packet, it must not generate a handshake. RX_LAST set and RCOUNT clear), and the second read inThis allows recovery from a condition where dicates the status of the SETUP packet. This register prothe ACK of the first SETUP token was lost by vides read-only access from the CPU bus. After reset it is the host. clear. 0 – Receive disabled. 1 – Receive enabled. IGN_OUT The Ignore OUT Tokens bit controls whether 7 6 5 4 3 0 OUT tokens are ignored. When this bit is set, Res. SETUP TOGGLE RX_LAST RCOUNT the endpoint ignores any OUT tokens directed to its configured address. 0 – Do not ignore OUT tokens. RCOUNT The Receive Count field reports the number of 1 – Ignore OUT tokens. bytes presently in the RX FIFO. This number IGN_SETUP The Ignore SETUP Tokens bit controls whethis never larger than 8 for Endpoint 0. er SETUP tokens are ignored. When this bit is RX_LAST The Receive Last Bytes bit indicates that an set, the endpoint ignores any SETUP tokens ACK was sent on completion of a successful directed to its configured address. receive operation. This bit is unchanged for 0 – Do not ignore SETUP tokens. zero-length packets. It is cleared when this 1 – Ignore SETUP tokens. register is read. 0 – No ACK was sent. 1 – An ACK was sent. TXFD The Transmit FIFO Data Byte is used to load the transmit FIFO. Software is expected to write only the packet payload data. The PID and CRC16 are created automatically. 89 www.national.com CP3BT10 FLUSH CP3BT10 FLUSH Writing 1 to the Flush bit flushes all data from ISO the control endpoint FIFOs, resets the endpoint to Idle state, clears the FIFO read and write pointer, and then clears itself. If the endpoint is currently using FIFO0 to transfer data on USB, flushing is delayed until after the transfer is done. This bit is cleared on reset. This bit is equivalent to FLUSH in the TXC0 register. 0 – Writing 0 has no effect. 1 – Writing 1 flushes the FIFOs. STALL 16.3.30 Receive Data 0 Register (RXD0) Reading the RXD0 register returns the data located at the current position of the receive read pointer of the Endpoint 0 FIFO. The register allows read-only access from the CPU bus. After reset, reading this register returns undefined data. 7 0 RXFD7:0 When the Isochronous bit is set, the endpoint is isochronous. This implies that no NAK is sent if the endpoint is not ready but enabled; i.e. if an IN token is received and no data is available in the FIFO to transmit, or if an OUT token is received and the FIFO is full since there is no USB handshake for isochronous transfers. 0 – Isochronous mode disabled. 1 – Isochronous mode enabled. The Stall bit can be used to enable STALL handshakes under the following conditions: The transmit FIFO is enabled and an IN token is received. The receive FIFO is enabled and an OUT token is received. A SETUP token does not cause a STALL handshake to be generated when this bit is set. 0 – Disable STALL handshakes. 1 – Enable STALL handshakes. 16.3.32 Transmit Status Register n (TXSn) Each of the three transmit endpoints has a TXSn register. The Receive FIFO Data Byte is used to un- The format of the TXSn registers is given below. The regisload the FIFO. Software should expect to read ters provide read-only access from the CPU bus. They are only the packet payload data. The PID and loaded with 1Fh at reset. CRC16 are removed from the incoming data stream automatically. 7 6 5 4 0 16.3.31 Endpoint Control Register n (EPCn) TX_URUN ACK_STAT TX_DONE TCOUNT Each unidirectional endpoint has an EPCn register. The format of the EPCn registers is defined below. These registers provide read/write access from the CPU bus. After reset, the TCOUNT The Transmission Count field reports the EPCn registers are clear. number of empty bytes available in the FIFO. If this number is greater than 31, a value of 31 is reported. 7 6 5 4 3 0 TX_DONE When set, the Transmission Done bit indiSTALL Res. ISO EP_EN EP cates that the endpoint responded to a USB packet. Three conditions can cause this bit to be set: EP The Endpoint Address field holds the end A data packet completed transmission in point address. response to an IN token with non-ISO opEP_EN When the Endpoint Enable bit is set, the eration. EP[3:0] field is used in address comparison, The endpoint sent a STALL handshake in together with the AD[6:0] field in the FAR regresponse to an IN token. ister. When clear, the endpoint does not re A scheduled ISO frame was transmitted or spond to any token on the USB bus. (The discarded. AD_EN bit in the FAR register is the global adThis bit is cleared when this register is read. dress compare enable for the USB node. If it is clear, the device does not respond to any address, without regard to the EP_EN state.) 0 – Address comparison is disabled. 1 – If the AD_EN bit is also set, address comparison is enabled. RXFD www.national.com 90 TX_URUN The Acknowledge Status bit is valid when the LAST TX_DONE bit is set. The meaning of the ACK_STAT bit differs depending on whether ISO or non-ISO operation is used (as selected by the ISO bit in the EPCn register). Non-Isochronous mode—This bit indicates the acknowledge status (from the host) about the ACK for the previously sent packet. This bit itself is set when an ACK is received; otherwise, it is clear. Isochronous mode—This bit is set if a frame number LSB match occurs (see Section 16.3.33), and data was sent in response to an IN token. Otherwise, this bit is cleared, the FIFO is flushed, and TX_DONE is set. The ACK_STAT bit is cleared when this regis- TOGGLE ter is read. The Transmit FIFO Underrun indicates whether the transmit FIFO became empty during a transmission, and no new data was written to the FIFO. If so, the Media Access Controller (MAC) forces a bit stuff error followed by an EOP. This bit is cleared when this register is read. 0 – No transmit FIFO underrun event occurred. 1 – Transmit FIFO underrun event occurred. 16.3.33 Transmit Command Register n (TXCn) Each of the transmit endpoints (1, 3, and 5) has a Transmit Command Register, TXCn. These registers provide read/ write access from the CPU bus. After reset the registers are clear. 7 6 5 4 3 2 1 0 IGN_ISOMSK TFWL RFF FLUSH TOGGLE LAST TX_EN TX_EN FLUSH The Transmission Enable bit enables data transmission from the FIFO. It is cleared by hardware after transmitting a single packet or after a STALL handshake in response to an IN token. It must be set by software to start packet transmission. 0 – Transmission disabled. 1 – Transmission enabled. RFF 91 The Last Byte bit indicates whether the entire packet has been written into the FIFO. This is used especially for streaming data to the FIFO while the actual transmission occurs. If the LAST bit is not set and the transmit FIFO becomes empty during a transmission, a stuff error followed by an EOP is forced on the bus. Zero length packets are indicated by setting this bit without writing any data to the FIFO. The transmit state machine transmits the payload data, CRC16, and the EOP signal before clearing this bit. 0 – Last byte of the packet has not been written to the FIFO. 1 – Last byte of the packet has been written to the FIFO. The function of the Toggle bit differs depending on whether ISO or non-ISO operation is used (as selected by the ISO bit in the EPCn register). Non-Isochronous mode—The TOGGLE bit specifies the PID used when transmitting the packet. A value of 0 causes a DATA0 PID to be generated, while a value of 1 causes a DATA1 PID to be generated. Isochronous mode—The TOGGLE bit and the LSB of the frame counter (FNL0) act as a mask for the TX_EN bit to allow pre-queueing of packets to specific frame numbers. (I.e. transmission is enabled only if bit 0 in the FNL register is set to TOGGLE.) If an IN token is not received while this condition is true, the contents of the FIFO are flushed with the next SOF. If the endpoint is set to ISO, data is always transferred with a DATA0 PID. This bit is not altered by hardware. Writing 1 to the Flush bit flushes all data from the corresponding transmit FIFO, resets the endpoint to Idle state, and clears both the FIFO read and write pointers. If the MAC is currently using the FIFO to transmit, data is flushed after the transmission is complete. After data flushing, this bit is cleared by hardware. 0 – Writing 0 has no effect. 1 – Writing 1 flushes the FIFO. The Refill FIFO bit is used to repeat a transmission for which no ACK was received. Setting the LAST bit to 1 automatically saves the Transmit Read Pointer (TXRP) to a buffer. When the RFF bit is set, the buffered TXRP is reloaded into the TXRP. This allows software to repeat the last transaction if no ACK was received from the host. If the MAC is currently using the FIFO to transmit, TXRP is reloaded only after the transmission is complete. After reload, this bit is cleared by hardware. 0 – No action. 1 – Reload the saved TXRP. www.national.com CP3BT10 ACK_STAT CP3BT10 TFWL The Transmit FIFO Warning Limit bits specify how many more bytes can be transmitted from the respective FIFO before an underrun condition occurs. If the number of bytes remaining in the FIFO is equal to or less than the selected warning limit, the TXWARN bit in the FWEV register is set. To avoid interrupts caused by setting this bit while the FIFO is being filled before a transmission begins, TXWARN is only set when transmission from the endpoint is enabled (TX_ENn in the TXCn register is set). See Table 40. 16.3.35 Receive Status Register n (RXSn) Each receive endpoint pipe (2, 4, and 6) has one RXSn register with the bits defined below. To allow a SETUP packet to be received after a zero length OUT packet is received, hardware contains two copies of this register. One holds the receive status of a zero length packet, and another holds the status of the next SETUP packet with data. If a zero length packet is followed by a SETUP packet, the first read of this register indicates the zero-length packet status, and the second read, the SETUP packet status. This register provides read-only access from the CPU bus. After reset it is clear. Table 40 Transmit FIFO Warning Limit TFWL Bytes Remaining in FIFO 00 TFWL disabled 01 ≤4 10 ≤8 11 ≤ 16 7 RCOUNT IGN_ISOMSK The Ignore ISO Mask bit has an effect only if the endpoint is set to be isochronous. If set, this bit disables locking of specific frame numbers with the alternate function of the TOGGLE bit. Therefore, data is transmitted upon TOGGLE reception of the next IN token. If clear, data is only transmitted when FNL0 matches TOGGLE. This bit is cleared after reset. 0 – Data transmitted only when FNL0 matches TOGGLE. 1 – Locking of frame numbers disabled. 16.3.34 Transmit Data Register n (TXDn) Each transmit FIFO has one TXDn register. Data written to the TXDn register is loaded into the transmit FIFO n at the current location of the transmit write pointer. The TXDn registers provide write-only access from the CPU bus. 0 SETUP TXFD TXFD The Transmit FIFO Data Byte is used to load the transmit FIFO. Software is expected to RX_ERR write only the packet payload data. The PID and CRC16 are inserted automatically in the transmit data stream. www.national.com 5 4 RX_ERR SETUP TOGGLE RX_LAST RX_LAST 7 6 92 3 0 RCOUNT The Receive Counter holds the number of bytes presently in the endpoint receive FIFO. If this number is greater than 15, a value of 15 is actually reported. The Receive Last Bytes bit indicates that an ACK was sent on completion of a successful receive operation. This bit is cleared when this register is read. 0 – No ACK was sent. 1 – An ACK was sent. The function of the Toggle bit differs depending on whether ISO or non-ISO operation is used (as controlled by the ISO bit in the EPCn register). Non-Isochronous mode—A value of 0 indicates that the last successfully received packet had a DATA0 PID, while a value of 1 indicates that this packet had a DATA1 PID. Non-Isochronous mode—This bit reflects the LSB of the frame number (FNL0) after a packet was successfully received for this endpoint. This bit is cleared by reading the RXSn register. The Setup bit indicates that the setup packet has been received. This bit is cleared when this register is read. 0 – Setup packet has not been received. 1 – Setup packet has been received. The Receive Error indicates a media error, such as bit-stuffing or CRC. If this bit is set, software must flush the respective FIFO. 0 – No receive error occurred. 1 – Receive error occurred. 16.3.37 Receive Data Register n (RXD) Each of the receive endpoints (2, 4, and 6) has one RXCn register. The registers provide read/write access from the CPU bus. Reading reserved bits returns undefined data. After reset, it is clear. Each of the three Receive Endpoint FIFOs has one RXD register. Reading the Receive Data register n returns the data located in the receive FIFO n at the current position of the receive read pointer. These registers provide read-only access from the CPU bus. 7 6 5 4 3 2 1 0 7 Res. RFWL Res. FLUSH IGN_SETUP Res. RX_EN 0 RXFD RX_EN The Receive Enable bit enables receiving packets. OUT packet reception is disabled after every data packet is received, or when a STALL handshake is returned in response to an OUT token. The RX_EN bit must be set to re-enable data reception. Reception of SETUP packets is always enabled. In the case of back-to-back SETUP packets (for a given endpoint) where a valid SETUP packet is received with no other intervening non-SETUP tokens, the Endpoint Controller discards the new SETUP packet and returns an ACK handshake. If any other reasons prevent the Endpoint Controller from accepting the SETUP packet, it must not generate a handshake. 0 – Receive disabled. 1 – Receive enabled. IGN_SETUP The Ignore SETUP Tokens bit controls whether SETUP tokens are ignored. When this bit is set, the endpoint ignores any SETUP tokens directed to its configured address. 0 – Do not ignore SETUP tokens. 1 – Ignore SETUP tokens. FLUSH Writing 1 to the Flush bit flushes all data from the corresponding receive FIFO, resets the endpoint to Idle state, and clears the FIFO read and write pointers. If the endpoint is currently using FIFO to receive data, flushing is delayed until after the transfer is complete. 0 – Writing 0 has no effect. 1 – Writing 1 flushes the FIFOs. RFWL The Receive FIFO Warning Limit field specifies how many more bytes can be received to the respective FIFO before an overrun condition occurs. If the number of empty bytes remaining in the FIFO is equal to or less than the selected warning limit, the RXWARN bit in the FWEV register is set. RXFD 16.4 The Receive FIFO Data Byte is used to read the receive FIFO. Software should expect to read only the packet payload data. The PID and CRC16 are terminated by the receive state machine. TRANSCEIVER INTERFACE Separate UVCC and UGND pins are provided for the USB transceiver, so it can be powered at the standard USB voltage of 3.3V while the other parts of the device run at other voltages. The USB transceiver is powered by the system, not the USB cable, so these pins must be connected to a power supply and the system ground. The on-chip USB transceiver does not have enough impedance to meet the USB specification requirement, so external 22-ohm resistors are required in series with the D+ and D- pins, as shown in Figure 29. +3.3V UVCC 22 D+ CP3BT10 22 D- USB Cable UGND DS123 Figure 29. USB Transceiver Interface Table 41 Receive FIFO Warning Limit RFWL Bytes Remaining in FIFO 00 RFWL disabled 01 ≤4 10 ≤8 11 ≤ 16 93 www.national.com CP3BT10 16.3.36 Receive Command Register n (RXCn) CP3BT10 17.0 Advanced Audio Interface The Advanced Audio Interface (AAI) provides a serial synchronous, full duplex interface to codecs and similar serial devices. The transmit and receive paths may operate asynchronously with respect to each other. Each path uses a 3wire interface consisting of a bit clock, a frame synchronization signal, and a data signal. The CPU interface can be either interrupt-driven or DMA. If the interface is configured for interrupt-driven I/O, data is buffered in the receive and transmit FIFOs. If the interface is configured for DMA, the data is buffered in registers. The AAI is functionally similar to a MotorolaTM Synchronous Serial Interface (SSI). Compared to a standard SSI implementation, the AAI interface does not support the so-called “On-demand Mode”. It also does not allow gating of the shift clocks, so the receive and transmit shift clocks are always active while the AAI is enabled. The AAI also does not support 12- and 24-bit data word length or more than 4 slots (words) per frame. The reduction of supported modes is acceptable, because the main purpose of the AAI is to connect to audio codecs, rather than to other processors (DSPs). 17.1.3 Serial Transmit Frame Sync (SFS) The SFS pin is a bidirectional signal which provides frame synchronization. In asynchronous mode, this signal is used as frame sync only by the transmitter. In synchronous mode, this signal is used as frame sync by both the transmitter and receiver. The frame sync signal may be generated internally, or it may be provided by an external source. 17.1.4 Serial Receive Data (SRD) The SRD pin is used as an input when data is shifted into the Audio Receive Shift Register (ARSR). In asynchronous mode, data on the SRD pin is sampled on the negative edge of the serial receive shift clock (SRCLK). In synchronous mode, data on the SRD pin is sampled on the negative edge of the serial shift clock (SCK). The data is shifted into ARSR with the most significant bit (MSB) first. 17.1.5 Serial Receive Clock (SRCLK) The SRCLK pin is a bidirectional signal that provides the receive serial shift clock in asynchronous mode. In this mode, data is sampled on the negative edge of SRCLK. The SRThe implementation of a FIFO as a 16-word receive and CLK signal may be generated internally or it may be providtransmit buffer is an additional feature, which simplifies ed by an external clock source. In synchronous mode, the communication and reduces interrupt load. Independent SCK pin is used as shift clock for both the receiver and DMA is provided for each of the four supported audio chan- transmitter, so the SRCLK pin is available for use as a gennels (slots). The AAI also provides special features and op- eral-purpose port pin or an auxiliary frame sync signal to acerating modes to simplify gain control in an external codec cess multiple slave devices (e.g. codecs) within a network and to connect to an ISDN controller through an IOM-2 (see Network mode). compatible interface. 17.1.6 Serial Receive Frame Sync (SRFS) 17.1 AUDIO INTERFACE SIGNALS 17.1.1 Serial Transmit Data (STD) The STD pin is used to transmit data from the serial transmit shift register (ATSR). The STD pin is an output when data is being transmitted and is in high-impedance mode when no data is being transmitted. The data on the STD pin changes on the positive edge of the transmit shift clock (SCK). The STD pin goes into high-impedance mode on the negative edge of SCK of the last bit of the data word to be transmitted, assuming no other data word follows immediately. If another data word follows immediately, the STD pin will not change to the high-impedance mode, instead remaining active. The data is shifted out with the most significant bit (MSB) first. 17.1.2 Serial Transmit Clock (SCK) The SCK pin is a bidirectional signal that provides the serial shift clock. In asynchronous mode, this clock is used only by the transmitter to shift out data on the positive edge. The serial shift clock may be generated internally or it may be provided by an external clock source. In synchronous mode, the SCK pin is used by both the transmitter and the receiver. Data is shifted out from the STD pin on the positive edge, and data is sampled on the SRD pin on the negative edge of SCK. www.national.com 94 The SRFS pin is a bidirectional signal that provides frame synchronization for the receiver in asynchronous mode. The frame sync signal may be generated internally, or it may be provided by an external source. In synchronous mode, the SFS signal is used as the frame sync signal for both the transmitter and receiver, so the SRFS pin is available for use as a general-purpose port pin or an auxiliary frame sync signal to access multiple slave devices (e.g. codecs) within a network (see Network mode). 17.2 AUDIO INTERFACE MODES There are two clocking modes: asynchronous mode and synchronous mode. These modes differ in the source and timing of the clock signals used to transfer data. When the AAI is generating the bit shift clock and frame sync signals internally, synchronous mode must be used. In asynchronous mode, an external frame sync signal must be used. There are two framing modes: normal mode and network mode. In normal mode, one word is transferred per frame. In network mode, up to four words are transferred per frame. A word may be 8 or 16 bits. The part of the frame which carries a word is called a slot. Network mode supports multiple external devices sharing the interface, in which each device is assigned its own slot. Separate frame sync signals are provided, so that each device is triggered to send or receive its data during its assigned slot. Asynchronous Mode IRQ Support In asynchronous mode, the receive and transmit paths of the audio interface operate independently, with each path using its own bit clock and frame sync signal. Independent clocks for receive and transmit are only used when the bit clock and frame sync signal are supplied externally. If the bit clock and frame sync signals are generated internally, both paths derive their clocks from the same set of clock prescalers. 17.2.2 Synchronous Mode In synchronous mode, the receive and transmit paths of the audio interface use the same shift clock and frame sync signal. The bit shift clock and frame sync signal for both paths are derived from the same set of clock prescalers. If the receiver interface is configured for interrupt-driven I/O (RXDSA0 = 0), all received data are loaded into the receive FIFO. An IRQ is asserted as soon as the number of data bytes or words in the receive FIFO is greater than a programmable warning limit. If the transmitter interface is configured for interrupt-driven I/O (TXDSA0 = 0), all data to be transmitted is read from the transmit FIFO. An IRQ is asserted as soon as the number data bytes or words available in the transmit FIFO is equal or less than a programmable warning limit. DMA Support If the receiver interface is configured for DMA (RXDSA0 = 1), received data is transferred from the ARSR into the DMA receive buffer 0 (ARDR0). A DMA request is asserted when 17.2.3 Normal Mode the ARDR0 register is full. If the transmitter interface is conIn normal mode, each rising edge on the frame sync signal figured for DMA (TXDSA0 = 1), data to be transmitted are marks the beginning of a new frame and also the beginning read from the DMA transmit buffer 0 (ATDR0). A DMA reof a new slot. A slot does not necessarily occupy the entire quest is asserted to the DMA controller when the ATDR0 frame. (A frame can be longer than the data word transmitregister is empty. ted after the frame sync pulse.) Typically, a codec starts transmitting a fixed length data word (e.g. 8-bit log PCM da- Figure 31 shows the data flow for IRQ and DMA mode in ta) with the frame sync signal, then the codec’s transmit pin normal Mode. returns to the high-impedance state for the remainder of the DMA frame. SRD Request 1 ARSR The Audio Receive Shift Register (ARSR) de-serializes received on the SRD pin (serial receiver data). Only the data sampled after the frame sync signal are treated as valid. If the interface is interrupt-driven, valid data bits are transferred from the ARSR to the receive FIFO. If the interface is configured for DMA, the data is transferred to the receive DMA register 0 (ARDR0). If the interface is configured for DMA, the DMA slot assignment bits must also be programmed to select slot 0. In this case, the audio data is transferred to or from the receive or transmit DMA register 0 (ARDR0/ATDR0). Figure 30 shows the frame timing while operating in normal mode with a long frame sync interval. Long Frame Sync (SFS/SRFS) Shift Data (STD/SRD) Data High-impedance Data Frame DS053 Figure 30. =1 A DS TX DMA Slot Assignment TXDSA = 0 RX FIFO IRQ DMA Request 0 STD ATSR The serial transmit data (STD) pin is only an active output while data is shifted out. After the defined number of data bits have been shifted out, the STD pin returns to the highimpedance state. For operation in normal mode, the Slot Count Select bits (SCS[1:0]) in the Global Configuration register (AGCR) must be loaded with 00b (one slot per frame). In addition, the Slot Assignment bits for receive and transmit must be programmed to select slot 0. ARDR 0 SA =1 ATDR 0 D RX DMA Slot Assignment RXDSA = 0 TX FIFO IRQ DS054 Figure 31. IRQ/DMA Support in Normal Mode Network Mode In network mode, each frame is composed of multiple slots. Each slot may transfer 8 or 16 bits. All of the slots in a frame must have the same length. In network mode, the sync signal marks the beginning of a new frame. Only frames with up to four slots are supported by this audio interface. More than two devices can communicate within a network using the same clock and data lines. The devices connected to the same bus use a time-multiplexed approach to share access to the bus. Each device has certain slots assigned to it, in which only that device is allowed to transfer data. One master device provides the bit clock and the frame sync signal(s). On all other (slave) devices, the bit clock and frame sync pins are inputs. Up to four slots can be assigned to the interface, as it supports up to four slots per frame. Any other slots within the frame are reserved for other devices. Normal Mode Frame 95 www.national.com CP3BT10 17.2.1 DMA Support On the receiver side, only the valid data bits which were received during the slots assigned to this interface are copied into the receive FIFO or DMA registers. The assignment of slots to the receiver is specified by the Receive Slot Assignment bits (RXSA) in the ATCR register. It can also be specified whether the received data is copied into the receive FIFO or into the corresponding DMA receive register. There is one DMA receive register (ARDRn) for each of the maximum four data slots. Each slot may be configured individually. Figure 33 illustrates the data flow for IRQ and DMA support in network mode, using four slots per frame and DMA support enabled for slots 0 and 1 in receive and transmit direction. If DMA support is enabled for a receive slot n (RXDSA0 = 1), all data received in this slot is only transferred from the ARSR into the corresponding DMA receive register (ARDRn). A DMA request is asserted when the ARDRn register is full. If DMA is enabled for a transmit slot n (TXDSAn = 1), all data to be transmitted in slot n are read from the corresponding DMA transmit register (ATDRn). A DMA request is asserted to the DMA controller when the ATDRn register is empty. ARDR 0 ta SRD DMA Slot Assignment Sl ot an 3 da ta RX FIFO High-impedance Slot1 Data (ignored) ATDR 0 Unused Slots STD ta Slot0 da ATSR ATDR 1 ata DS055 Figure 32. IRQ DMA Request 0 DMA Request 2 ot 0 Frame ot Sl DMA Slot Assignment Network Mode Frame ot If DMA is not enabled for a receive slot n (RXDSAn = 0), all data received in this slot is loaded into the receive FIFO. An IRQ is asserted as soon as the number of data bytes or words in the receive FIFO is greater than a configured warning limit. If DMA is not enabled for a transmit slot n (TXDSAn = 0), all data to be transmitted in this slot are read from the transmit FIFO. An IRQ is asserted as soon as the number data bytes or words available in the transmit FIFO is equal or less than a configured warning limit. 96 1d ATDR 2 ATDR 3 Sl IRQ Support www.national.com ARDR 2 ARDR 3 2 d Data (valid) DMA Request 3 0 ata 1d ot Sl Long Frame Sync (SFS/SRFS) Data (ignored) DMA Request 1 ot Sl Figure 32 shows the frame timing while operating in network mode with four slots per frame, slot 1 assigned to the interface, and a long frame sync interval. Shift Data (STD/SRD) ARDR 1 da ARSR Sl CP3BT10 The transmitter only drives data on the STD pin during slots which have been assigned to this interface. During all other slots, the STD output is in high-impedance mode, and data can be driven by other devices. The assignment of slots to the transmitter is specified by the Transmit Slot Assignment bits (TXSA) in the ATCR register. It can also be specified whether the data to be transmitted is transferred from the transmit FIFO or the corresponding DMA transmit register. There is one DMA transmit register (ATDRn) for each of the maximum four data slots. Each slot can be configured independently. 2 an d 3 da ta TX FIFO IRQ DS056 Figure 33. IRQ/DMA Support in Network Mode If the interface operates in synchronous mode, the receiver uses the transmit bit clock (SCK) and transmit frame sync signal (SFS). This allows the pins used for the receive bit clock (SRCLK) and receive frame sync (SRFS) to be used as additional frame sync signals in network mode. The extra frame sync signals are useful when the audio interface communicates to more than one codec, because codecs typically start transmission immediately after the frame sync pulse. The SRCLK pin is driven with a frame sync pulse at the beginning of the second slot (slot 1), and the SRFS pin is driven with a frame sync pulse at the beginning of slot 2. Figure 34 shows a frame timing diagram for this configuration, using the additional frame sync signals on SRCLK and SRFS to address up to three devices. Pideal = fAudio In / fbit = 12 MHz / 256 kHz = 46.875 SFS Therefore, the real prescaler value is 47. This results in a bit clock error equal to: SRCLK (auxiliary frame sync) fbit_error = (fbit - fAudio In/Preal) / fbit × 100 = (256 kHz - 12 MHz/47) / 256 kHz × 100 = 0.27% SRFS (auxiliary frame sync) 17.4 Data from/to Data from/to Data from/to Codec 1 Codec 2 Codec 3 STD/SRD Slot 0 Slot 1 Slot 2 Slot 3 Frame DS057 Figure 34. 17.3 Accessing Three Devices in Network Mode BIT CLOCK GENERATION An 8-bit prescaler is provided to divide the audio interface input clock down to the required bit clock rate. Software can choose between two input clock sources, a primary and a secondary clock source. On the CP3BT10, the two optional input clock sources are the 12-MHz Aux1 clock (also used for the Bluetooth LLC) and the 48-MHz PLL output clock (also used by the USB node). The input clock is divided by the value of the prescaler BCPRS[7:0] + 1 to generate the bit clock. FRAME CLOCK GENERATION The clock for the frame synchronization signals is derived from the bit clock of the audio interface. A 7-bit prescaler is used to divide the bit clock to generate the frame sync clock for the receive and transmit operations. The bit clock is divided by FCPRS + 1. In other words, the value software must write into the ACCR.FCPRS field is equal to the bit number per frame minus one. The frame may be longer than the valid data word but it must be equal to or larger than the 8- or 16-bit word. Even if 13-, 14-, or 15-bit data is being used, the frame width must always be at least 16 bits wide. In addition, software can specify the length of a long frame sync signal. A long frame sync signal can be either 6, 13, 14, 15, or 16 bits long, depending on the external codec being used. The frame sync length can be configured by the Frame Sync Length field (FSL) in the AGCR register. 17.5 AUDIO INTERFACE OPERATION 17.5.1 Clock Configuration The Aux1 clock (generated by the Clock module described The bit clock rate fbit can be calculated by the following in Section 11.8) must be configured, because it is the time base for the AAI module. Software must write an appropriequation: ate divisor to the ACDIV1 field of the PRSAC register to profbit = n × fSample × Data Length vide a 12 MHz input clock. Software also must enable the Aux1 clock by setting the ACE1 bit in the CRCTRL register. n = Number of Slots per Frame For example: fSample = Sample Frequency in Hz Data Length = Length of data word in multiples of 8 bits PRSAC &= 0xF0; The ideal required prescaler value Pideal can be calculated as follows: // Set Aux1 prescaler to 1 (F = 12 MHz) CRCTRL |= ACE1; // Enable Aux1 clk Pideal = fAudio In / fbit 17.5.2 Interrupts The real prescaler must be set to an integer value, which The interrupt logic of the AAI combines up to four interrupt should be as close as possible to the ideal prescaler value, sources and generates one interrupt request signal to the to minimize the bit clock error, fbit_error. Interrupt Control Unit (ICU). fbit_error [%] = (fbit - fAudio In/Preal) / fbit × 100 The four interrupt sources are: Example: The audio interface is used to transfer 13-bit linear PCM data for one audio channel at a sample rate of 8k samples per second. The input clock of the audio interface is 12 MHz. Furthermore, the codec requires a minimum bit clock of 256 kHz to operate properly. Therefore, the number of slots per frame must be set to 2 (network mode) although actually only one slot (slot 0) is used. The codec and the audio interface will put their data transmit pins in TRI-STATE mode after the PCM data word has been transferred. The required bit clock rate fbit can be calculated by the following equation: RX FIFO Overrun - ASCR.RXEIP = 1 RX FIFO Almost Full (Warning Level) - ASCR.RXIP = 1 TX FIFO Under run - ASCR.TXEIP = 1 TX FIFO Almost Empty (Warning Level) - ASCR.TXIP=1 In addition to the dedicated input to the ICU for handling these interrupt sources, the Serial Frame Sync (SFS) signal is an input to the MIWU (see Section 13.0), which can be programmed to generate edge-triggered interrupts. fbit = n × fSample × Data Length = 2 × 8 kHz × 16 = 256 kHz 97 www.national.com CP3BT10 The ideal required prescaler value Pideal can be calculated as follows: CP3BT10 Figure 35 shows the interrupt structure of the AAI. from the FIFO to ATSR is performed (while the FIFO is already empty), a transmit FIFO underrun occurs. In this event, the read pointer (TRP) will be decremented by 1 (incremented by 15) and the previous data word will be transmitted again. A transmit FIFO underrun is indicated by the TXU bit in the Audio Interface Transmit Status and Control Register (ATSCR). Also, no transmit interrupt will be generated (even if enabled). RXIE RXIP = 1 RXEIE When the TRP is equal to the TWP and the last access to the FIFO was a write operation (to the ATFR), the FIFO is full. If an additional write to ATFR is performed, a transmit FIFO overrun occurs. This error condition is not prevented by hardware. Software must ensure that no transmit overrun occurs. AAI Interrupt RXEIP = 1 TXIE TXIP = 1 The transmit frame synchronization pulse on the SFS pin and the transmit shift clock on the SCK pin may be generated internally, or they can be supplied by an external source. TXEIE TXEIP = 1 17.5.5 DS155 Figure 35. AAI Interrupt Structure 17.5.3 Normal Mode In normal mode, each frame sync signal marks the beginning of a new frame and also the beginning of a new slot, since each frame only consists of one slot. All 16 receive and transmit FIFO locations hold data for the same (and only) slot of a frame. If 8-bit data are transferred, only the low byte of each 16-bit FIFO location holds valid data. 17.5.4 Receive At the receiver, the received data on the SRD pin is shifted into ARSR on the negative edge of SRCLK (or SCK in synchronous mode), following the receive frame sync pulse, SRFS (or SFS in synchronous mode). Transmit Once the interface has been enabled, transmit transfers are initiated automatically at the beginning of every frame. The beginning of a new frame is identified by a frame sync pulse. Following the frame sync pulse, the data is shifted out from the ATSR to the STD pin on the positive edge of the transmit data shift clock (SCK). DMA Operation When a complete data word has been received through the SRD pin, the new data word is copied to the receive DMA register 0 (ARDR0). A DMA request is asserted when the ARDR0 register is full. If a new data word is received while the ARDR0 register is still full, the ARDR0 register will be overwritten with the new data. FIFO Operation When a complete word has been received, it is transferred to the receive FIFO at the current location of the Receive FIFO Write Pointer (RWP). Then, the RWP is automatically incremented by 1. A read from the Audio Receive FIFO Register (ARFR) results in a read from the receive FIFO at the current location When a complete data word has been transmitted through of the Receive FIFO Read Pointer (RRP). After every read the STD pin, a new data word is reloaded from the transmit operation from the receive FIFO, the RRP is automatically DMA register 0 (ATDR0). A DMA request is asserted when incremented by 1. the ATDR0 register is empty. If a new data word must be When the RRP is equal to the RWP and the last access to transmitted while the ATDR0 register is still empty, the prethe FIFO was a copy operation from the ARFR, the receive vious data will be re-transmitted. FIFO is full. When a new complete data word has been shifted into ARSR while the receive FIFO was already full, the FIFO Operation shift register overruns. In this case, the new data in the When a complete data word has been transmitted through ARSR will not be copied into the FIFO and the RWP will not the STD pin, a new data word is loaded from the transmit be incremented. A receive FIFO overrun is indicated by the FIFO from the current location of the Transmit FIFO Read RXO bit in the Audio Interface Receive Status and Control Pointer (TRP). After that, the TRP is automatically increRegister (ARSCR). No receive interrupt will be generated mented by 1. (even if enabled). A write to the Audio Transmit FIFO Register (ATFR) results When the RWP is equal to the TWP and the last access to in a write to the transmit FIFO at the current location of the the receive FIFO was a read from the ARFR, a receive FIFO Transmit FIFO Write Pointer (TWP). After every write operunderrun has occurred. This error condition is not prevented ation to the transmit FIFO, TWP is automatically incrementby hardware. Software must ensure that no receive undered by 1. run occurs. When the TRP is equal to the TWP and the last access to The receive frame synchronization pulse on the SRFS pin the FIFO was a read operation (a transfer to the ATSR), the (or SFS in synchronous mode) and the receive shift clock on transmit FIFO is empty. When an additional read operation the SRCLK (or SCK in synchronous mode) may be generDMA Operation www.national.com 98 17.5.6 Network Mode In network mode, each frame sync signal marks the beginning of new frame. Each frame can consist of up to four slots. The audio interface operates in a similar way to normal mode, however, in network mode the transmitter and receiver can be assigned to specific slots within each frame as described below. 17.5.7 Transmit The transmitter only shifts out data during the assigned slot. During all other slots the STD output is in TRI-STATE mode. DMA Operation ferred to the receive FIFO or DMA receive register which were received during the assigned time slots. A receive interrupt or DMA request is initiated when this occurs. DMA Operation When a complete data word has been received through the SRD pin in a slot n, the new data word is transferred to the corresponding receive DMA register n (ARDRn). A DMA request is asserted when the ARDRn register is full. If a new slot n data word is received while the ARDRn register is still full, the ARDRn register will be overwritten with the new data. FIFO Operation When a complete word has been received, it is transferred to the receive FIFO at the current location of the Receive FIFO Write Pointer (RWP). After that, the RWP is automatically incremented by 1. Therefore, data received in the next slot is copied to the next higher FIFO location. When a complete data word has been transmitted through the STD pin, a new data word is reloaded from the corresponding transmit DMA register n (ATDRn). A DMA request is asserted when ATDRn is empty. If a new data word must A read from the Audio Receive FIFO Register (ARFR) rebe transmitted in a slot n while ATDRn is still empty, the pre- sults in a read from the receive FIFO at the current location vious slot n data will be retransmitted. of the Receive FIFO Read Pointer (RRP). After every read operation from the receive FIFO, the RRP is automatically FIFO Operation incremented by 1. When a complete data word has been transmitted through the STD pin, a new data word is reloaded from the transmit When the RRP is equal to the RWP and the last access to FIFO from the current location of the Transmit FIFO Read the FIFO was a transfer to the ARFR, the receive FIFO is Pointer (TRP). After that, the TRP is automatically incre- full. When a new complete data word has been shifted into mented by 1. Therefore, the audio data to be transmitted in the ARSR while the receive FIFO was already full, the shift the next slot of the frame is read from the next FIFO loca- register overruns. In this case, the new data in the ARSR will not be transferred to the FIFO and the RWP will not be intion. cremented. A receive FIFO overrun is indicated by the RXO A write to the Audio Transmit FIFO Register (ATFR) results bit in the Audio Interface Receive Status and Control Regisin a write to the transmit FIFO at the current location of the ter (ARSCR). No receive interrupt will be generated (even if Transmit FIFO Write Pointer (TWP). After every write operenabled). ation to the transmit FIFO, the TWP is automatically increWhen the current RWP is equal to the TWP and the last acmented by 1. cess to the receive FIFO was a read from ARFR, a receive When the TRP is equal to the TWP and the last access to FIFO underrun has occurred. This error condition is not prethe FIFO was a read operation (transfer to the ATSR), the vented by hardware. Software must ensure that no receive transmit FIFO is empty. When an additional read operation underrun occurs. from the FIFO to the ATSR is performed (while the FIFO is already empty), a transmit FIFO underrun occurs. In this The receive frame synchronization pulse on the SRFS pin case, the read pointer (TRP) will be decremented by 1 (in- (or SFS in synchronous mode) and the receive shift clock on cremented by 15) and the previous data word will be trans- the SRCLK (or SCK in synchronous mode) may be genermitted again. A transmit FIFO underrun is indicated by the ated internally, or they can be supplied by an external TXU bit in the Audio Interface Transmit Status and Control source. Register (ATSCR). No transmit interrupt will be generated 17.6 COMMUNICATION OPTIONS (even if enabled). If the current TRP is equal to the TWP and the last access 17.6.1 Data Word Length to the FIFO was a write operation (to the ATFR), the FIFO is full. If an additional write to the ATFR is performed, a transmit FIFO overrun occurs. This error condition is not prevented by hardware. Software must ensure that no transmit overrun occurs. The word length of the audio data can be selected to be either 8 or 16 bits. In 16-bit mode, all 16 bits of the transmit and receive shift registers (ATSR and ARSR) are used. In 8bit mode, only the lower 8 bits of the transmit and receive shift registers (ATSR and ARSR) are used. The transmit frame synchronization pulse on the SFS pin 17.6.2 Frame Sync Signal and the transmit shift clock on the SCK pin may be generated internally, or they can be supplied by an external source. The audio interface can be configured to use either long or short frame sync signals to mark the beginning of a new 17.5.8 Receive data frame. If the corresponding Frame Sync Select (FSS) The receive shift register (ARSR) receives data words of all bit in the Audio Control and Status register is clear, the reslots in the frame, regardless of the slot assignment of the ceive and/or transmit path generates or recognizes short interface. However, only those ARSR contents are trans- frame sync pulses with a length of one bit shift clock period. When these short frame sync pulses are used, the transfer 99 www.national.com CP3BT10 ated internally, or they can be supplied by an external source. CP3BT10 of the first data bit or the first slot begins at the first positive edge of the shift clock after the negative edge on the frame sync pulse. Some codecs require an inverted frame sync signal. This is available by setting the Inverted Frame Sync bit in the AGCR register. If the corresponding Frame Sync Select (FSS) bit in the Audio Control and Status register is set, the receive and/or transmit path generates or recognizes long frame sync pulses. For 8-bit data, the frame sync pulse generated will be 6 bit shift clock periods long, and for 16-bit data the frame sync pulse can be configured to be 13, 14, 15, or 16 bit shift clock periods long. When receiving frame sync, it should be active on the first bit of data and stay active for a least two bit clock periods. It must go low for at least one bit clock period before starting a new frame. When long frame sync pulses are used, the transfer of the first word (first slot) begins at the first positive edge of the bit shift clock after the positive edge of the frame sync pulse. Figure 36 shows examples of short and long frame sync pulses. 17.6.3 Bit Shift Clock (SCK/SRCLK) Shift Data (STD/SRD) D0 D1 D2 D3 D4 D5 D6 Audio Control Data The audio interface provides the option to fill a 16-bit slot with up to three data bits if only 13, 14, or 15 PCM data bits are transmitted. These additional bits are called audio control data and are appended to the PCM data stream. The AAI can be configured to append either 1, 2, or 3 audio control bits to the PCM data stream. The number of audio data bits to be used is specified by the 2-bit Audio Control On (ADMACR. ACO[1:0]) field. If the ACO field is not equal to 0, the specified number of bits are taken from the Audio Control Data field (ADMACR. ACD[2:0]) and appended to the data stream during every transmit operation. The ADC[0] bit is the first bit added to the transmit data stream after the last PCM data bit. Typically, these bits are used for gain control, if this feature is supported by the external PCM codec.Figure 37 shows a 16-bit slot comprising a 13-bit PCM data word plus three audio control bits. D7 Short Frame Sync Pulse Long Frame Sync Pulse DS156 Figure 36. Short and Long Frame Sync Pulses SCK SFS STD D0 D1 D2 D3 D4 D5 D6 D7 D8 D9 D10 D11 D12 ACD2 ACD1 ACD0 13-bit PCM Data Word Audio Control Bits 16-bit Slot DS161 Figure 37. Audio Slot with Audio Control Data www.national.com 100 IOM-2 Mode The IOM-2 interface has the following properties: The AAI can operate in a special IOM-2 compatible mode to allow to connect to an external ISDN controller device. In this IOM-2 mode, the AAI can only operate as a slave, i.e. the bit clock and frame sync signal is provided by the ISDN controller. The AAI only supports the B1 and B2 data of the IOM-2 channel 0, but ignores the other two IOM-2 channels. The AAI handles the B1 and B2 data as one 16-bit data word. Bit clock of 1536 kHz (output from the ISDN controller) Frame repetition rate of 8 ksps (output from the ISDN controller) Double-speed bit clock (one data bit is two bit clocks wide) B1 and B2 data use 8-bit log PCM format Long frame sync pulse Figure 38 shows the structure of an IOM-2 Frame. SFS STD/SRD B1 B2 M C IC1 IC2 M IOM-2 Channel 1 IOM-2 Channel 0 C C IOM-2 Channel 2 IOM-2 Frame (125 µs) DS162 Figure 38. IOM-2 Frame Structure Figure 39 shows the connections between an ISDN controller and a CP3BT10 using a standard IOM-2 interface for the B1/B2 data communication and the external bus interface (IO Expansion) for controlling the ISDN controller. SCK Bit Clock SFS Frame Sync STD Data In SRD Data Out A[7:0] Address D[7:0] Data SELIO Chip Select CP3BT10 ISDN Controller To connect the AAI to an ISDN controller through an IOM-2 compatible interface, the AAI needs to be configured in this way: The AAI must be in IOM-2 Mode (AGCR.IOM2 = 1). The AAI operates in synchronous mode (AGCR.ASS = 0). The AAI operates as a slave, therefore the bit clock and frame sync source selection must be set to external (ACGR.IEFS = 1, ACGR.IEBC = 1). The frame sync length must be set to long frame sync (ACGR.FSS = 1). The data word length must be set to 16-bit (AGCR.DWL = 1). The AAI must be set to normal mode (AGCR.SCS[1:0] = 0). The internal frame rate must be 8 ksps (ACCR = 00BE). 17.6.5 RD Output Enable DS157 Loopback Mode In loopback mode, the STD and SRD pins are internally connected together, so data shifted out through the ATSR register will be shifted into the ARSR register. This mode may be used for development, but it also allows testing the transmit and receive path without external circuitry, for example during Built-In-Self-Test (BIST). Figure 39. CP3BT10/ISDN Controller Connections 101 www.national.com CP3BT10 17.6.4 CP3BT10 17.6.6 17.7 Freeze Mode The audio interface provides a FREEZE input, which allows to freeze the status of the audio interface while a development system examines the contents of the FIFOs and registers. When the FREEZE input is asserted, the audio interface behaves as follows: The receive FIFO or receive DMA registers are not updated with new data. The receive status bits (RXO, RXE, RXF, and RXAF) are not changed, even though the receive FIFO or receive DMA registers are read. The transmit shift register (ATSR) is not updated with new data from the transmit FIFO or transmit DMA registers. The transmit status bits (TXU, TXF, TXE, and TXAE) are not changed, even though the transmit FIFO or transmit DMA registers are written. The time at which these registers are frozen will vary because they operate from a different clock than the one used to generate the freeze signal. www.national.com 102 AUDIO INTERFACE REGISTERS Table 42 Audio Interface Registers Name Address Description ARFR FF FD40h Audio Receive FIFO Register ARDR0 FF FD42h Audio Receive DMA Register 0 ARDR1 FF FD44h Audio Receive DMA Register 1 ARDR2 FF FD46h Audio Receive DMA Register 2 ARDR3 FF FD48h Audio Receive DMA Register 3 ATFR FF FD4Ah Audio Transmit FIFO Register ATDR0 FF FD4Ch Audio Transmit DMA Register 0 ATDR1 FF FD4Eh Audio Transmit DMA Register 1 ATDR2 FF FD50h Audio Transmit DMA Register 2 ATDR3 FF FD52h Audio Transmit DMA Register 3 AGCR FF FD54h Audio Global Configuration Register AISCR FF FD56h Audio Interrupt Status and Control Register ARSCR FF FD58h Audio Receive Status and Control Register ATSCR FF FD5Ah Audio Transmit Status and Control Register ACCR FF FD5Ch Audio Clock Control Register ADMACR FF FD5Eh Audio DMA Control Register Audio Receive FIFO Register (ARFR) 17.7.3 The Audio Receive FIFO register shows the receive FIFO location currently addressed by the Receive FIFO Read Pointer (RRP). The receive FIFO receives 8-bit or 16-bit data from the Audio Receive Shift Register (ARSR), when the ARSR is full. In 8-bit mode, only the lower byte of the ARFR is used, and the upper byte contains undefined data. In 16-bit mode, a 16-bit word is copied from ARSR into the receive FIFO. The CPU bus master has read-only access to the receive FIFO, represented by the ARFR register. After reset, the receive FIFO (ARFR) contains undefined data. 7 The ATFR register shows the transmit FIFO location currently addressed by the Transmit FIFO Write Pointer (TWP). The Audio Transmit Shift Register (ATSR) receives 8-bit or 16-bit data from the transmit FIFO, when the ATSR is empty. In 8-bit mode, only the lower 8-bit portion of the ATSR is used, and the upper byte is ignored (not transferred into the ATSR). In 16-bit mode, a 16-bit word is copied from the transmit FIFO into the ATSR. The CPU bus master has write-only access to the transmit FIFO, represented by the ATFR register. After reset, the transmit FIFO (ATFR) contains undefined data. 7 0 15 8 ARFH 17.7.2 The Audio Receive FIFO Low Byte shows the lower byte of the receive FIFO location currently addressed by the Receive FIFO Read Pointer (RRP). The Audio Receive FIFO High Byte shows the upper byte of the receive FIFO location currently addressed by the Receive FIFO Read Pointer (RRP). In 8-bit mode, ARFH contains undefined data. ATFL ATFH 17.7.4 Audio Receive DMA Register n (ARDRn) The ARDRn register contains the data received within slot n, assigned for DMA support. In 8-bit mode, only the lower 8-bit portion of the ARDRn register is used, and the upper byte contains undefined data. In 16-bit mode, a 16-bit word is transferred from the Audio Receive Shift Register (ARSR) into the ARDRn register. The CPU bus master, typically a DMA controller, has read-only access to the receive DMA registers. After reset, these registers are clear. 7 0 ATDL 15 8 8 ATDH ARDH ARDH Audio Transmit DMA Register n (ATDRn) 7 ARDL ARDL The Audio Transmit Low Byte field represents the lower byte of the transmit FIFO location currently addressed by the Transmit FIFO Write Pointer (TWP). In 16-bit mode, the Audio Transmit FIFO High Byte field represents the upper byte of the transmit FIFO location currently addressed by the Transmit FIFO Write Pointer (TWP). In 8bit mode, the ATFH field is not used. The ATDRn register contains the data to be transmitted in slot n, assigned for DMA support. In 8-bit mode, only the lower 8-bit portion of the ATDRn register is used, and the upper byte is ignored (not transferred into the ATSR). In 16bit mode, the whole 16-bit word is transferred into the ATSR. The CPU bus master, typically a DMA controller, has writeonly access to the transmit DMA registers. After reset, these registers are clear. 0 15 8 ATFH ARFH ARFL 0 ATFL ARFL 15 Audio Transmit FIFO Register (ATFR) The Audio Receive DMA Low Byte field receives the lower byte of the audio data copied from the ARSR. In 16-bit mode, the Audio Receive DMA High Byte field receives the upper byte of the audio data word copied from ARSR. In 8-bit mode, the ARDH register holds undefined data. ATDL ATDH 103 The Audio Transmit DMA Low Byte field holds the lower byte of the audio data. In 16-bit mode, the Audio Transmit DMA High Byte field holds the upper byte of the audio data word. In 8-bit mode, the ATDH field is ignored. www.national.com CP3BT10 17.7.1 CP3BT10 17.7.5 Audio Global Configuration Register (AGCR) IEFS The AGCR register controls the basic operation of the interface. The CPU bus master has read/write access to the AGCR register. After reset, this register is clear. 7 6 5 4 IEBC FSS IEFS 3 SCS 2 1 0 LPB DWL ASS 10 9 8 CTF CRF FSS 15 14 13 CLKEN AAIEN IOM2 ASS DWL LPB SCS 12 11 IFS FSL The Asynchronous/Synchronous Mode Select bit controls whether the audio interface operates in Asynchronous or in Synchronous mode. After reset the ASS bit is clear, so the Synchronous mode is selected by default. 0 – Synchronous mode. 1 – Asynchronous mode. The Data Word Length bit controls whether the transferred data word has a length of 8 or 16 bits. After reset, the DWL bit is clear, so 8bit data words are used by default. 0 – 8-bit data word length. 1 – 16-bit data word length. The Loop Back bit enables the loop back mode. In this mode, the SRD and STD pins are internally connected. After reset the LPB bit is clear, so by default the loop back mode is disabled. 0 – Loop back mode disabled. 1 – Loop back mode enabled. The Slot Count Select field specifies the number of slots within each frame. If the number of slots per frame is equal to 1, the audio interface operates in normal mode. If the number of slots per frame is greater than 1, the interface operates in network mode. After reset all SCS bits are cleared, so by default the audio interface operates in normal mode. IEBC CRF CTF FSL SCS Number of Slots per Frame Mode 00 1 Normal mode 01 2 Network mode FSL Frame Sync Length 10 3 Network mode 00 13 bit clocks 11 4 Network mode 01 14 bit clocks 10 15 bit clocks 11 16 bit clocks IFS www.national.com The Internal/External Frame Sync bit controls, whether the frame sync signal for the receiver and transmitter are generated internally or provided from an external source. After reset, the IEFS bit is clear, so the frame synchronization signals are generated internally by default. 0 – Internal frame synchronization signal. 1 – External frame synchronization signal. The Frame Sync Select bit controls whether the interface (receiver and transmitter) uses long or short frame synchronization signals. After reset the FSS bit is clear, so short frame synchronization signals are used by default. 0 – Short (bit length) frame synchronization signal. 1 – Long (word length) frame synchronization signal. The Internal/External Bit Clock bit controls whether the bit clocks for receiver and transmitter are generated internally or provided from an external source. After reset, the IEBC bit is clear, so the bit clocks are generated internally by default. 0 – Internal bit clock. 1 – External bit clock. The Clear Receive FIFO bit is used to clear the receive FIFO. When this bit is written with a 1, all pointers of the receive FIFO are set to their reset state. After updating the pointers, the CRF bit will automatically be cleared again. 0 – Writing 0 has no effect. 1 – Writing 1 clears the receive FIFO. The Clear Transmit FIFO bit is used to clear the transmit FIFO. When this bit is written with a 1, all pointers of the transmit FIFO are set to their reset state. After updating the pointers, the CTF bit will automatically be cleared again. 0 – Writing 0 has no effect. 1 – Writing 1 clears the transmit FIFO. The Frame Sync Length field specifies the length of the frame synchronization signal, when a long frame sync signal (FSS = 1) and a 16-bit data word length (DWL = 1) are used. If an 8-bit data word length is used, long frame syncs are always 6 bit clocks in length. 104 The Inverted Frame Sync bit controls the polarity of the frame sync signal. 0 – Active-high frame sync signal. 1 – Active-low frame sync signal. The IOM-2 Mode bit selects the normal PCM interface mode or a special IOM-2 mode used to connect to external ISDN controller devices. The AAI can only operate as a slave in the IOM-2 mode, i.e. the bit clock and frame sync signals are provided by the ISDN controller. If the IOM2 bit is clear, the AAI operates in the normal PCM interface mode used to connect to external PCM codecs and other PCM audio devices. 0 – IOM-2 mode disabled. 1 – IOM-2 mode enabled. The AAI Enable bit controls whether the Advanced Audio Interface is enabled. All AAI registers provide read/write access while (CLKEN = 1) AAIEN is clear. The AAIEN bit is clear after reset. 0 – AAI module disabled. 1 – AAI module enabled. The Clock Enable bit controls whether the Advanced Audio Interface clock is enabled. The CLKEN bit must be set to allow access to any AAI register. It must also be set before any other bit of the AGCR can be set. The CLKEN bit is clear after reset. 0 – AAI module clock disabled. 1 – AAI module clock enabled. AAIEN CLKEN 17.7.6 TXIE TXEIE RXIP RXEIP Audio Interrupt Status and Control Register (AISCR) The ASCR register is used to specify the source and the conditions, when the audio interface interrupt is asserted to TXIP the Interrupt Control Unit. It also holds the interrupt pending bits and the corresponding interrupt clear bits for each audio interface interrupt source. The CPU bus master has read/ write access to the ASCR register. After reset, this register is clear. 7 6 5 4 3 2 1 TXEIP 0 TXEIP TXIP RXEIP RXIP TXEIE TXIE RXEIE RXIE 15 12 Reserved 11 10 9 8 TXEIC TXIC RXEIC RXIC RXIC RXIE RXEIE The Receive Interrupt Enable bit controls whether receive interrupts are generated. If the RXIE bit is clear, no receive interrupt will RXEIC be generated. 0 – Receive interrupt disabled. 1 – Receive interrupt enabled. The Receive Error Interrupt Enable bit con- TXIC trols whether receive error interrupts are generated. Setting this bit enables a receive error interrupt, when the Receive Buffer Overrun (RXOR) bit is set. If the RXEIE bit is clear, no TXEIC receive error interrupt will be generated. 0 – Receive error interrupt disabled. 1 – Receive error interrupt enabled. 105 The Transmit Interrupt Enable bit controls whether transmit interrupts are generated. Setting this bit enables a transmit interrupt, when the Transmit Buffer Almost Empty (TXAE) bit is set. If the TXIE bit is clear, no interrupt will be generated. 0 – Transmit interrupt disabled. 1 – Transmit interrupt enabled. The Transmit Error Interrupt Enable bit controls whether transmit error interrupts are generated. Setting this bit to 1 enables a transmit error interrupt, when the Transmit Buffer Underrun (TXUR) bit is set. If the TXEIE bit is clear, no transmit error interrupt will be generated. 0 – Transmit error interrupt disabled. 1 – Transmit error interrupt enabled. The Receive Interrupt Pending bit indicates that a receive interrupt is currently pending. The RXIP bit is cleared by writing a 1 to the RXIC bit. The RXIP bit provides read-only access. 0 – No receive interrupt pending. 1 – Receive interrupt pending. The Receive Error Interrupt Pending bit indicates that a receive error interrupt is currently pending. The RXEIP bit is cleared by writing a 1 to the RXEIC bit. The RXEIP bit provides read-only access. 0 – No receive error interrupt pending. 1 – Receive error interrupt pending. The Transmit Interrupt Pending bit indicates that a transmit interrupt is currently pending. The TXIP bit is cleared by writing a 1 to the TXIC bit. The TXIP bit provides read-only access. 0 – No transmit interrupt pending. 1 – Transmit interrupt pending. Transmit Error Interrupt Pending. This bit indicates that a transmit error interrupt is currently pending. The TXEIP bit is cleared by software by writing a 1 to the TXEIC bit. The TXEIP bit provides read-only access. 0 – No transmit error interrupt pending. 1 – Transmit error interrupt pending. The Receive Interrupt Clear bit is used to clear the RXIP bit. 0 – Writing a 0 to the RXIC bit is ignored. 1 – Writing a 1 clears the RXIP bit. The Receive Error Interrupt Clear bit is used to clear the RXEIP bit. 0 – Writing a 0 to the RXEIC bit is ignored. 1 – Writing a 1 clears the RXEIP bit. The Transmit Interrupt Clear bit is used to clear the TXIP bit. 0 – Writing a 0 to the TXIC bit is ignored. 1 – Writing a 1 clears the TXIP bit. The Transmit Error Interrupt Clear bit is used to clear the TXEIP bit. 0 – Writing a 0 to the TXEIC bit is ignored. 1 – Writing a 1 clears the TXEIP bit. www.national.com CP3BT10 IOM2 CP3BT10 17.7.7 Audio Receive Status and Control Register (ARSCR) The following table shows the slot assignment scheme. The ARSCR register is used to control the operation of the receiver path of the audio interface. It also holds bits which report the current status of the receive FIFO. The CPU bus master has read/write access to the ASCR register. At reset, this register is loaded with 0004h. 7 4 RXSA 15 12 RXFWL RXAF RXF RXE RXO RXSA 3 2 RXO RXE 1 0 RXF RXAF 11 8 RXDSA RXDSA The Receive Buffer Almost Full bit is set when the number of data bytes/words in the receive buffer is equal to the specified warning limit. 0 – Receive FIFO below warning limit. 1 – Receive FIFO is almost full. The Receive Buffer Full bit is set when the receive buffer is full. The RXF bit is set when the RWP is equal to the RRP and the last access was a write to the FIFO. 0 – Receive FIFO is not full. 1 – Receive FIFO full. The Receive Buffer Empty bit is set when the the RRP is equal to the RWP and the last access to the FIFO was a read operation (read from ARDR). 0 – Receive FIFO is not empty. 1 – Receive FIFO is empty. The Receive Overflow bit indicates that a receive shift register has overrun. This occurs, when a completed data word has been shifted RXFWL into ARSR, while the receive FIFO was already full (the RXF bit was set). In this case, the new data in ARSR will not be copied into the FIFO and the RWP will not be incremented. Also, no receive interrupt and DMA request will generated (even if enabled). 0 – No overflow has occurred. 1 – Overflow has occurred. The Receive Slot Assignment field specifies which slots are recognized by the receiver of the audio interface. Multiple slots may be enabled. If the frame consists of less than 4 slots, the RXSA bits for unused slots are ignored. For example, if a frame only consists of 2 slots, RXSA bits 2 and 3 are ignored. www.national.com 106 RXSA Bit Slots Enabled RXSA0 0 RXSA1 1 RXSA2 2 RXSA3 3 After reset the RXSA field is clear, so software must load the correct slot assignment. The Receive DMA Slot Assignment field specifies which slots (audio channels) are supported by DMA. If the RXDSA bit is set for an assigned slot n (RXSAn = 1), the data received within this slot will not be transferred into the receive FIFO, but will instead be written into the corresponding Receive DMA data register (ARDRn). A DMA request n is asserted, when the ARDRn is full and if the RMA bit n is set. If the RXSD bit for a slot is clear, the RXDSA bit is ignored. The following table shows the DMA slot assignment scheme. RXDSA Bit Slots Enabled for DMA RXDSA0 0 RXDSA1 1 RXDSA2 2 RXDSA3 3 The Receive FIFO Warning Level field specifies when a receive interrupt is asserted. A receive interrupt is asserted, when the number of bytes/words in the receive FIFO is greater than the warning level value. An RXFWL value of 0 means that a receive interrupt is asserted if one or more bytes/words are in the RX FIFO. After reset, the RXFWL bit is clear. Audio Transmit Status and Control Register (ATSCR) The ASCR register controls the basic operation of the interface. It also holds bits which report the current status of the audio communication. The CPU bus master has read/write access to the ASCR register. At reset, this register is loaded with F003h. 7 4 TXSA 15 12 TXFWL TXAE TXE TXF TXU TXSA 3 2 TXU TXF 1 0 TXSA Bit Slots Enabled TXSA0 0 TXSA1 1 TXSA2 2 TXSA3 3 TXE TXAE 11 8 TXDSA TXDSA The Transmit FIFO Almost Empty bit is set when the number of data bytes/words in transmit buffer is equal to the specified warning limit. 0 – Transmit FIFO above warning limit. 1 – Transmit FIFO at or below warning limit. The Transmit FIFO Empty bit is set when the transmit buffer is empty. The TXE bit is set to one every time the TRP is equal to the TWP and the last access to the FIFO was read operation (into ATSR). 0 – Transmit FIFO not empty. 1 – Transmit FIFO empty. The Transmit FIFO Full bit is set when the TWP is equal to the TRP and the last access to the FIFO was write operation (write to ATDR). 0 – Transmit FIFO not full. 1 – Transmit FIFO full. The Transmit Underflow bit indicates that the TFWL transmit shift register (ATSR) has underrun. This occurs when the transmit FIFO was already empty and a complete data word has been transferred. In this case, the TRP will be decremented by 1 and the previous data will be retransmitted. No transmit interrupt and no DMA request will be generated (even if enabled). 0 – Transmit underrun occurred. 1 – Transmit underrun did not occur. The Transmit Slot Assignment field specifies during which slots the transmitter is active and drives data through the STD pin. The STD pin is in high impedance state during all other slots. If the frame consists of less than 4 slots, the TXSA bits for unused slots are ignored. For example, if a frame only consists of 2 slots, TXSA bits 2 and 3 are ignored. The following table shows the slot assignment scheme. 107 After reset, the TXSA field is clear, so software must load the correct slot assignment. The Transmit DMA Slot Assignment field specifies which slots (audio channels) are supported by DMA. If the TXDSA bit is set for an assigned slot n (TXSAn = 1), the data to be transmitted within this slot will not be read from the transmit FIFO, but will instead be read from the corresponding Transmit DMA data register (ATDRn). A DMA request n is asserted when the ATDRn is empty. If the TSA bit for a slot is clear, the TXDSA bit is ignored. The following table shows the DMA slot assignment scheme. TXDSA Bit Slots Enabled for DMA TXDSA0 0 TXDSA1 1 TXDSA2 2 TXDSA3 3 The Transmit FIFO Warning Level field specifies when a transmit interrupt is asserted. A transmit interrupt is asserted when the number of bytes or words in the transmit FIFO is equal or less than the warning level value. A TXFWL value of Fh means that a transmit interrupt is asserted if one or more bytes or words are available in the transmit FIFO. At reset, the TXFWL field is loaded with Fh. www.national.com CP3BT10 17.7.8 CP3BT10 17.7.9 Audio Clock Control Register (ACCR) ignored. The following table shows the receive DMA request scheme. The ACCR register is used to control the bit timing of the audio interface. After reset, this register is clear. 7 1 FCPRS 15 RMD DMA Request Condition 0 0000 None CSS 0001 ARDR0 full 0010 ARDR1 full 0011 ARDR0 full or ARDR1 full x1xx Not supported on CP3BT10 8 BCPRS CSS FCPRS BCPRS The Clock Source Select bit selects one out of two possible clock sources for the audio interTMD face. After reset, the CSS bit is clear. 0 – The Aux1 clock is used to clock the Audio Interface. 1 – The 48-MHz USB clock is used to clock the Audio Interface. The Frame Clock Prescaler is used to divide the bit clock to generate the frame clock for the receive and transmit operations. The bit clock is divided by (FCPRS + 1). After reset, the FCPRS field is clear. The maximum allowed bit clock rate to achieve an 8 kHz frame clock is 1024 kHz. This value must be set correctly even if the frame sync is generated externally. The Bit Clock Prescaler is used to divide the audio interface clock (selected by the CSS bit) to generate the bit clock for the receive and transmit operations. The audio interface input clock is divided by (BCPRS + 1). After reset, the BCPRS[7:0] bits are clear. 17.7.10 Audio DMA Control Register (ADMACR) ACD ACO 4 3 TMD 15 13 Reserved RMD 0 RMD 12 11 ACO 10 8 ACD 17.8 The Receive Master DMA field specify which slots (audio channels) are supported by DMA, i.e. when a DMA request is asserted to the DMA controller. If the RMDn bit is set for an assigned slot n (RXDSAn = 1), a DMA request n is asserted, when the ARDRn is full. If the RXDSAn bit for a slot is clear, the RMDn bit is www.national.com The Transmit Master DMA field specifies which slots (audio channels) are supported by DMA, i.e. when a DMA request is asserted to the DMA controller. If the TMD bit is set for an assigned slot n (TXDSAn = 1), a DMA request n is asserted, when the ATDRn register is empty. If the TXDSA bit for a slot is clear, the TMD bit is ignored. The following table shows the transmit DMA request scheme. TMD DMA Request Condition 0000 None 0001 ATDR0 empty 0010 ATDR1 empty 0011 ATDR0 empty or ATDR1 empty x1xx 1xxx The ADMACR register is used to control the DMA support of the audio interface. In addition, it is used to configure the automatic transmission of the audio control bits. After reset, this register is clear. 7 1xxx Not supported on CP3BT10 The Audio Control Data field is used to fill the remaining bits of a 16-bit slot if only 13, 14, or 15 bits of PCM audio data are transmitted. The Audio Control Output field controls the number of control bits appended to the PCM data word. 00 – No Audio Control bits are appended. 01 – Append ACD0. 10 – Append ACD1:0. 11 – Append ACD2:0. USAGE HINTS When the Advanced Audio Interface is active, it can lock up if the receive FIFO is cleared by writing 1 to the AGCR.CRF bit, the transmit FIFO is cleared by writing 1 to the AGCR.CTF bit, or the module is disabled by clearing the AGCR.AAIEN bit. Follow this procedure to disable the Advanced Audio Interface: 108 1. Clear the ARSCR.RXSA and ATSCR.TXSA fields. 2. Wait at least 10 receive/transmit clock cycles. 3. Clear the AGCR.AAIEN bit. The CVSD/PCM module performs conversion between CVSD data and PCM data, in which the CVSD encoding is as defined in the Bluetooth specification and the PCM encoding may be 8-bit µ-Law, 8-bit A-Law, or 13-bit to 16-bit Linear. The CVSD conversion module operates at a fixed rate of 125 µs (8 kHz) per PCM sample. On the CVSD side, there 2 MHz Clock Input is a read and a write FIFO allowing up to 8 words of data to be read or written at the same time. On the PCM side, there is a double-buffered register requiring data to be read and written every 125 µs. The intended use is to move CVSD data into the module with a CVSD interrupt handler, and to move PCM data with DMA. Figure 40 shows a block diagram of the CVSD to PCM module. Interrupt DMA 16-Bit 8 kHz 16-Bit 64 kHz u/A-Law 16-Bit 8 kHz 1-Bit 64 kHz CVSD Encoder 16-Bit Shift Reg CVSD Decoder 16-Bit Shift Reg Filter Engine 16-Bit u/A-Law 64 kHz 1-Bit 64 kHz Peripheral Bus DS058 Figure 40. CVSD/PCM Converter Block Diagram 18.1 OPERATION Inside the module, a filter engine receives the 8 kHz stream of 16-bit samples and interpolates to generate a 64 kHz The Aux2 clock (generated by the Clock module described stream of 16-bit samples. This goes into a CVSD encoder in Section 11.8) must be configured, because it drives the which converts the data into a single-bit delta stream using CVSD module. Software must set its prescaler to provide a the CVSD parameters as defined by the Bluetooth specifi2 MHz input clock based upon the System Clock (usually cation. There is a similar path that reverses this process 12 MHz). This is done by writing an appropriate divisor to converting the CVSD 64 kHz bit stream into a 64 kHz 16-bit the ACDIV2 field of the PRSAC register. Software must also data stream. The filter engine then decimates this stream enable the Aux2 clock by setting the ACE2 bit within the into an 8 kHz, 16-bit data stream. CRCTRL register. For example: PRSAC &= 0x0f; 18.2 // Set Aux2 prescaler to generate During conversion between CVSD and PCM, any PCM format changes are done automatically depending on whether the PCM data is µ-Law, A-Law, or Linear. In addition to this, a separate function can be used to convert between the various PCM formats as required. Conversion is performed by setting up the control bit CVCTL1.PCMCONV to define the conversion and then writing to the LOGIN and LINEARIN registers and reading from the LOGOUT and LINEAROUT registers. There is no delay in the conversion operation and it does not have to operate at a fixed rate. It will only convert between µ-Law/A-Law and linear, not directly between µLaw and A-Law. (This could easily be achieved by converting between µ-Law and linear and between linear and ALaw.) // 2 MHz (Fsys = 12 MHz) PRSAC |= 0x50; CRCTRL |= ACE2; // Enable Aux2 clk The module converts between PCM data and CVSD data at a fixed rate of 8 kHz per PCM sample. Due to compression, the data rate on the CVSD side is only 4 kHz per CVSD sample. PCM CONVERSIONS If PCM interrupts are enabled (PCMINT is set) every 125 µs (8 kHz) an interrupt will occur and the interrupt handler can operate on some or all of the four audio streams CVSD in, CVSD out, PCM in, and PCM out. Alternatively, a DMA request is issued every 125 µs and the DMA controller is used If a conversion is performed between linear and µ-Law log to move the PCM data between the CVSD/PCM module PCM data, the linear PCM data are treated in the leftand the audio interface. aligned 14-bit linear data format with the two LSBs unused. If CVSD interrupts are enabled, an interrupt is issued when If a conversion is performed between linear and A-Law log either one of the CVSD FIFOs is almost empty or almost full. PCM data, the linear PCM data are treated in the leftOn the PCM data side there is double buffering, and on the aligned 13-bit linear data format with the three LSBs unCVSD side there is an eight word (8 × 16-bit) FIFO for the used. read and write paths. 109 www.national.com CP3BT10 18.0 CVSD/PCM Conversion Module CP3BT10 If the module is only used for PCM conversions, the CVSD been transferred to the audio interface, it will be overwritten clock can be disabled by clearing the CVSD Clock Enable with the new PCM sample. bit (CLKEN) in the control register. If there are only three unread words left, the CVSD In Nearly Empty bit (CVNE) is set and, if enabled (CVSDINT = 1), an 18.3 CVSD CONVERSION interrupt request is generated. The CVSD/PCM converter module transforms either 8-bit logarithmic or 13- to 16-bit linear PCM samples at a fixed If the CVSD In FIFO is empty, the CVSD In Empty bit (CVE) rate of 8 ksps. The CVSD to PCM conversion format must is set and, if enabled (CVSDERRINT = 1), an interrupt rebe specified by the CVSDCONV control bits in the CVSD quest is generated. If the converter core reads from an already empty CVSD In FIFO, the FIFO automatically returns Control register (CVCTRL). a checkerboard pattern to guarantee a minimum level of disThe CVSD algorithm is designed for 2’s complement 16-bit tortion of the audio stream. data and is tuned for best performance with typical voice daINTERRUPT GENERATION ta. Mild distortion will occur for peak signals greater than -6 18.6 dB. The Bluetooth CVSD standard is designed for best per- An interrupt is generated in any of the following cases: formace with typical voice signals: nominaly -6dB with occasional peaks to 0dB rather than full-scale inputs. Distortion When a new PCM sample has been written into the PCMOUT register and the CVCTRL.PCMINT bit is set. of signals greater than -6dB is not considered detrimental to subjective quality tests for voice-band applications and al- When a new PCM sample has been read from the PCMIN register and the CVCTRL.PCMINT bit is set. lows for greater clarity for signals below -6dB. The gain of When the CVSD In FIFO is nearly empty the input device should be tuned with this in mind. (CVSTAT.CVNE = 1) and the CVCTRL.CVSDINT bit is If required, the RESOLUTION field of the CVCTRL register set. can be used to optimize the level of the 16-bit linear input When the CVSD Out FIFO is nearly full data by providing attenuations (right-shifts with sign exten(CVSTAT.CVNF = 1) and the CVCTRL.CVSDINT bit is tion) of 1, 2, or 3 bits. set. Log data is always 8 bit, but to perform the CVSD conver- When the CVSD In FIFO is empty (CVSTAT.CVE = 1) and the CVCTRL.CVSDERRINT bit is set. sion, the log data is first converted to 16-bit 2’s complement linear data. A-law and u-law conversion can also slightly af- When the CVSD Out FIFO is full (CVSTAT.CVF = 1) and the CVCTRL.CVSDERRINT bit is set. fect the optimum gain of the input data. The CVCTRL.RESOLUTION field can be used to attenuate the data if required. Both the CVSD In and CVSD Out FIFOs have a size of If the resolution is not set properly, the audio signal may be 8 × 16 bit (8 words). The warning limits for the two FIFOs is set at 5 words. (The CVSD In FIFO interrupt will occur when clipped or have reduced attenuation. there are 3 words left in the FIFO, and the CVSD Out FIFO 18.4 PCM TO CVSD CONVERSION interrupt will occur when there are 3 or less empty words left The converter core reads out the double-buffered PCMIN in the FIFO.) The limit is set to 5 words because Bluetooth register every 125 µs and writes a new 16-bit CVSD data audio data is transferred in packages composed of 10 or stream into the CVSD Out FIFO every 250 µs. If the PCMIN multiples of 10 bytes. buffer has not been updated with a new PCM sample beDMA SUPPORT tween two reads from the CVSD core, the old PCM data is 18.7 used again to maintain a fixed conversion rate. Once a new The CVSD module can operate with any of four DMA chan16-bit CVSD data stream has been calculated, it is copied nels. Four DMA channels are required for processor independent operation. Both receive and transmit for CVSD into the 8 × 16-bit wide CVSD Out FIFO. If there are only three empty words (16-bit) left in the FIFO, data and PCM data can be enabled individually. The CVSD/ the nearly full bit (CVNF) is set, and, if enabled PCM module asserts a DMA request to the on-chip DMA controller under the following conditions: (CVSDINT = 1), an interrupt request is asserted. If the CVSD Out FIFO is full, the full bit (CVF) is set, and, if The DMAPO bit is set and the PCMOUT register is full, because it has been updated by the converter core with enabled (CVSDERRINT = 1), an interrupt request is asserta new PCM sample. (The DMA controller can read out ed. In this case, the CVSD Out FIFO remains unchanged. one PCM data word from the PCMOUT register.) Within the interrupt handler, the CPU can read out the new The DMAPI bit is set and the PCMIN register is empty, CVSD data. If the CPU reads from an already empty CVSD because it has been read by the converter core. (The Out FIFO, a lockup of the FIFO logic may occur which perDMA controller can write one new PCM data word into sists until the next reset. Software must check the the PCMIN register.) CVOUTST field of the CVSTAT register to read the number The DMACO bit is set and a new 16-bit CVSD data of valid words in the FIFO. Software must not use the CVNF stream has been copied into the CVSD Out FIFO. (The bit as an indication of the number of valid words in the FIFO. DMA controller can read out one 16-bit CVSD data word from the CVSD Out FIFO.) 18.5 CVSD TO PCM CONVERSION The DMACI bit is set and a 16-bit CVSD data stream has The converter core reads from the CVSD In FIFO every been read from the CVSD In FIFO. (The DMA controller 250 µs and writes a new PCM sample into the PCMOUT can write one new 16-bit CVSD data word into the CVSD buffer every 125 µs. If the previous PCM data has not yet In FIFO.) www.national.com 110 Table 43 CVSD/PCM Registers Name Address Description The trigger for DMA may also trigger an interrupt if the corresponding enable bits in the CVCTRL register is set. Therefore care must be taken when setting the desired interrupt and DMA enable bits. The following conditions must be avoided: LINEAROUT FF FC2Eh Linear PCM Data Output Register CVCTRL FF FC30h CVSD Control Register Setting the PCMINT bit and either of the DMAPO or DMAPI bits. Setting the CVSDINT bit and either of the DMACO or DMACI bits. CVSTAT FF FC32h CVSD Status Register 18.8 FREEZE The CVSD/PCM module provides support for an In-SystemEmulator by means of a special FREEZE input. While FREEZE is asserted the module will exhibit the following behavior: CVSD In FIFO will not have data removed by the converter core. CVSD Out FIFO will not have data added by the converter core. PCM Out buffer will not be updated by the converter core. The Clear-on-Read function of the following status bits in the CVSTAT register is disabled: PCMINT CVE CVF 18.9 18.9.1 CVSD Data Input Register (CVSDIN) The CVSDIN register is a 16-bit wide, write-only register. It is used to write CVSD data into the CVSD to PCM converter FIFO. The FIFO is 8 words deep. The CVSDIN bit 15 represents the CVSD data bit at t = t0, CVSDIN bit 0 represents the CVSD data bit at t = t0 - 250 ms. 15 0 CVSDIN 18.9.2 CVSD Data Output Register (CVSDOUT) The CVSDOUT register is a 16-bit wide read-only register. It is used to read the CVSD data from the PCM to CVSD converter. The FIFO is 8 words deep. Reading the CVSDOUT register after reset returns undefined data. 15 CVSD/PCM CONVERTER REGISTERS 0 CVSDOUT Table 43 lists the CVSD/PCM registers. Table 43 CVSD/PCM Registers Name Address Description CVSDIN FF FC20h CVSD Data Input Register CVSDOUT FF FC22h CVSD Data Output Register PCMIN FF FC24h PCM Data Input Register PCMOUT FF FC26h PCM Data Output Register LOGIN FF FC28h Logarithmic PCM Data Input Register LOGOUT FF FC2Ah Logarithmic PCM Data Output Register LINEARIN FF FC2Ch Linear PCM Data Input Register 18.9.3 PCM Data Input Register (PCMIN) The PCMIN register is a 16-bit wide write-only register. It is used to write PCM data to the PCM to CVSD converter via the peripheral bus. It is double-buffered, providing a 125 µs period for an interrupt or DMA request to respond. 15 0 PCMIN 18.9.4 PCM Data Output Register (PCMOUT) The PCMOUT register is a 16-bit wide read-only register. It is used to read PCM data from the CVSD to PCM converter. It is double-buffered, providing a 125 µs period for an interrupt or DMA request to respond. After reset the PCMOUT register is clear. 15 0 PCMOUT 111 www.national.com CP3BT10 The CVSD/PCM module only supports indirect DMA transfers. Therefore, transferring PCM data between the CVSD/ PCM module and another on-chip module requires two bus cycles. CP3BT10 18.9.5 Logarithmic PCM Data Input Register (LOGIN) The LOGIN register is an 8-bit wide write-only register. It is used to receive 8-bit logarithmic PCM data from the peripheral bus and convert it into 13-bit linear PCM data. 7 0 LOGIN 18.9.6 Logarithmic PCM Data Output Register (LOGOUT) The LOGOUT register is an 8-bit wide read-only register. It holds logarithmic PCM data that has been converted from linear PCM data. After reset, the LOGOUT register is clear. 7 0 LOGOUT 18.9.7 Linear PCM Data Input Register (LINEARIN) The LINEARIN register is a 16-bit wide write-only register. The data is left-aligned. When converting to A-law, bits 2:0 are ignored. When converting to µ-law, bits 1:0 are ignored. 15 0 LINEARIN 18.9.8 Linear PCM Data Output Register (LINEAROUT) The LINEAROUT register is a 16-bit wide read-only register. The data is left-aligned. When converting from A-law, bits 2:0 are clear. When converting from µ-law, bits 1:0 are clear. After reset, this register is clear. 15 0 LINEAROUT 18.9.9 CVSD Control Register (CVCTRL) The CVCTRL register is a 16-bit wide, read/write register that controls the mode of operation and of the module’s interrupts. At reset, all implemented bits are cleared. 7 6 DMA PO DMA CI 15 14 13 5 4 3 2 CVSD DMA CVSD PCM ERRCO INT INT INT 12 11 10 1 0 CLK CVEN EN 9 8 Res. RESOLUTION PCMCONV CVSDCONV DMAPI www.national.com CVEN The Module Enable bit enables or disables the CVSD conversion module interface. When the bit is set, the interface is enabled which allows read and write operations to the rest of the module. When the bit is clear, the module is disabled. When the module is disabled the status register CVSTAT will be cleared to its reset state. 0 – CVSD module enabled. 1 – CVSD module disabled. CLKEN The CVSD Clock Enable bit enables the 2MHz clock to the filter engine and CVSD encoders and decoders. 0 – CVSD module clock disabled. 1 – CVSD module clock enabled. PCMINT The PCM Interrupt Enable bit controls generation of the PCM interrupt. If set, this bit enables the PCM interrupt. If the PCMINT bit is clear, the PCM interrupt is disabled. After reset, this bit is clear. 0 – PCM interrupt disabled. 1 – PCM interrupt enabled. CVSDINT The CVSD FIFO Interrupt Enable bit controls generation of the CVSD interrupt. If set, this bit enables the CVSD interrupt that occurs if the CVSD In FIFO is nearly empty or the CVSD Out FIFO is nearly full. If the CVSDINT bit is clear, the CVSD nearly full/nearly empty interrupt is disabled. After reset, this bit is clear. 0 – CVSD interrupt disabled. 1 – CVSD interrupt enabled. CVSDERRINT The CVSD FIFO Error Interrupt Enable bit controls generation of the CVSD error interrupt. If set, this bit enables an interrupt to occur when the CVSD Out FIFO is full or the CVSD In FIFO is empty. If the CVSDERRORINT bit is clear, the CVSD full/empty interrupt is disabled. After reset, this bit is clear. 0 – CVSD error interrupt disabled. 1 – CVSD error interrupt enabled. DMACO The DMA Enable for CVSD Out bit enables hardware DMA control for reading CVSD data from the CVSD Out FIFO. If clear, DMA support is disabled. After reset, this bit is clear. 0 – CVSD output DMA disabled. 1 – CVSD output DMA enabled. DMACI The DMA Enable for CVSD In bit enables hardware DMA control for writing CVSD data into the CVSD In FIFO. If clear, DMA support is disabled. After reset, this bit is clear. 0 – CVSD input DMA disabled. 1 – CVSD input DMA enabled. DMAPO The DMA Enable for PCM Out bit enables hardware DMA control for reading PCM data from the PCMOUT register. If clear, DMA support is disabled. After reset, this bit is clear. 0 – PCM output DMA disabled. 1 – PCM output DMA enabled. 112 The DMA Enable for PCM In bit enables hard- CVNF ware DMA control for writing PCM data into the PCMIN register. If cleared, DMA support is disabled. After reset, this bit is clear. 0 – PCM input DMA disabled. 1 – PCM input DMA enabled. CVSDCONV The CVSD to PCM Conversion Format field specifies the PCM format for CVSD/PCM conversions. After reset, this field is clear. 00 – CVSD <-> 8-bit µ-Law PCM. 01 – CVSD <-> 8-bit A-Law PCM. 10 – CVSD <-> Linear PCM. 11 – Reserved. PCMCONV The PCM to PCM Conversion Format bit selects the PCM format for PCM/PCM conversions. PCMINT 0 – Linear PCM <-> 8-bit µ-Law PCM 1 – Linear PCM <-> 8-bit A-Law PCM RESOLUTION The Linear PCM Resolution field specifies the attenuation of the PCM data for the linear PCM to CVSD conversions by right shifting and sign extending the data. This affects the log PCM data as well as the linear PCM data. The log data is converted to either left-justified CVE zero-stuffed 13-bit (A-law) or 14-bit (u-law). The RESOLUTION field can be used to compensate for any change in average levels resulting from this conversion. After reset, these two bits are clear. 00 – No shift. 01 – 1-bit attentuation. 10 – 2-bit attentuation. 11 – 3-bit attentuation. 18.9.10 CVSD Status Register (CVSTAT) The CVSTAT register is a 16-bit wide, read-only register that holds the status information of the CVSD/PCM module. At reset, and if the CVCTL1.CVEN bit is clear, all implemented bits are cleared. 7 5 CVINST 4 CVF 15 3 2 0 CVE PCMINT CVNF CVNE 11 Reserved 1 CVF 10 8 CVOUTST CVINST CVNE The CVSD In FIFO Nearly Empty bit indicates when only three CVSD data words are left in the CVSD In FIFO, so new CVSD data should be written into the CVSD In FIFO. If the CVSDINT bit is set, an interrupt will be asserted CVOUTST when the CVNE bit is set. If the DMACI bit is set, a DMA request will be asserted when this bit is set. The CVNE bit is cleared when the CVSTAT register is read. 0 – CVSD In FIFO is not nearly empty. 1 – CVSD In FIFO is nearly empty. 113 The CVSD Out FIFO Nearly Full bit indicates when only three empty word locations are left in the CVSD Out FIFO, so the CVSD Out FIFO should be read. If the CVSDINT bit is set, an interrupt will be asserted when the CVNF bit is set. If the DMACO bit is set, a DMA request will be asserted when this bit is set. Software must not rely on the CVNF bit as an indicator of the number of valid words in the FIFO. Software must check the CVOUTST field to read the number of valid words in the FIFO. The CVNF bit is cleared when the CVSTAT register is read. 0 – CVSD Out FIFO is not nearly full. 1 – CVSD Out FIFO is nearly full. The PCM Interrupt bit set indicates that the PCMOUT register is full and needs to be read or the PCMIN register is empty and needs to be loaded with new PCM data. The PCMINT bit is cleared when the CVSTAT register is read, unless the device is in FREEZE mode. 0 – PCM does not require service. 1 – PCM requires loading or unloading. The CVSD In FIFO Empty bit indicates when the CVSD In FIFO has been read by the CVSD converter while the FIFO was already empty. If the CVSDERRORINT bit is set, an interrupt will be asserted when the CVE bit is set. The CVE bit is cleared when the CVSTAT register is read, unless the device is in FREEZE mode. 0 – CVSD In FIFO has not been read while empty. 1 – CVSD In FIFO has been read while empty. The CVSD Out FIFO Full bit set indicates whether the CVSD Out FIFO has been written by the CVSD converter while the FIFO was already full. If the CVSDERRORINT bit is set, an interrupt will be asserted when the CVF bit is set. The CVF bit is cleared when the CVSTAT register is read, unless the device is in FREEZE mode. 0 – CVSD Out FIFO has not been written while full. 1 – CVSD Out FIFO has been written while full. The CVSD In FIFO Status field reports the current number of empty 16-bit word locations in the CVSD In FIFO. When the FIFO is empty, the CVINST field will read as 111b. When the FIFO holds 7 or 8 words of data, the CVINST field will read as 000b. CVSD Out FIFO Status field reports the current number of valid 16-bit CVSD data words in the CVSD Out FIFO. When the FIFO is empty, the CVOUTST field will read as 000b. When the FIFO holds 7 or 8 words of data, the CVOUTST field will read as 111b. www.national.com CP3BT10 DMAPI CP3BT10 19.0 UART Module The UART module is a full-duplex Universal Asynchronous Receiver/Transmitter that supports a wide range of software-programmable baud rates and data formats. It handles automatic parity generation and several error detection schemes. of data from the UART, it de-asserts the clear-to-send (CTS) signal which causes the UART to pause after sending the current frame (if any). The UART asserts the ready-to-send (RTS) signal to the peripheral when it is ready to send a character. The UART module offers the following features: 19.2 Full-duplex double-buffered receiver/transmitter Programmable baud rate Programmable framing formats: 7, 8, or 9 data bits; even, odd, or no parity; one or two stop bits (mark or space) Hardware parity generation for data transmission and parity check for data reception Interrupts on “transmit ready” and “receive ready” conditions, separately enabled Software-controlled break transmission and detection Internal diagnostic capability Automatic detection of parity, framing, and overrun errors Hardware flow control (CTS and RTS signals) DMA capability UART OPERATION The UART normally operates in asynchronous mode. There are two special-purpose modes, called attention and diagnostic. This section describes the operating modes of the UART. 19.2.1 Asynchronous Mode The asynchronous mode of the UART enables the device to communicate with other devices using just two communication signals: transmit and receive. In asynchronous mode, the transmit shift register (TSFT) and the transmit buffer (UTBUF) double-buffer the data for transmission. To transmit a character, a data byte is loaded in the UTBUF register. The data is then transferred to the TSFT register. While the TSFT register is shifting out the 19.1 FUNCTIONAL OVERVIEW current character (LSB first) on the TXD pin, the UTBUF Figure 41 is a block diagram of the UART module showing register is loaded by software with the next byte to be transthe basic functional units in the UART: mitted. When TSFT finishes transmission of the last stop bit Transmitter of the current frame, the contents of UTBUF are transferred Receiver to the TSFT register and the Transmit Buffer Empty bit (UT Baud Rate Generator BE) is set. The UTBE bit is automatically cleared by the Control and Error Detection UART when software loads a new character into the UTBUF The Transmitter block consists of an 8-bit transmit shift reg- register. During transmission, the UXMIP bit is set high by ister and an 8-bit transmit buffer. Data bytes are loaded in the UART. This bit is reset only after the UART has sent the parallel from the buffer into the shift register and then shifted last stop bit of the current character and the UTBUF register is empty. The UTBUF register is a read/write register. The out serially on the TXD pin. TSFT register is not software accessible. The Receiver block consists of an 8-bit receive shift register and an 8-bit receive buffer. Data is received serially on the In asynchronous mode, the input frequency to the UART is RXD pin and shifted into the shift register. Once eight bits 16 times the baud rate. In other words, there are 16 clock have been received, the contents of the shift register are cycles per bit time. In asynchronous mode, the baud rate generator is always the UART clock source. transferred in parallel to the receive buffer. The receive shift register (RSFT) and the receive buffer (URBUF) double buffer the data being received. The UART receiver continuously monitors the signal on the RXD pin for a low level to detect the beginning of a start bit. On sensing The Baud Rate Generator generates the bit shift clock. It this low level, the UART waits for seven input clock cycles consists of two registers and a two-stage counter. The regand samples again three times. If all three samples still inisters are used to specify a prescaler value and a baud rate dicate a valid low, then the receiver considers this to be a divisor. The first stage of the counter divides the UART clock valid start bit, and the remaining bits in the character frame based on the value of the programmed prescaler to create are each sampled three times, around the mid-bit position. a slower clock. The second stage of the counter creates the For any bit following the start bit, the logic value is found by baud rate clock by dividing the output of the first stage majority voting, i.e. the two samples with the same value debased on the programmed baud rate divisor. fine the value of the data bit. Figure 42 illustrates the proThe Control and Error Detection block contains the UART cess of start bit detection and bit sampling. control registers, control logic, error detection circuit, parity Data bits are sensed by taking a majority vote of three samgenerator/checker, and interrupt generation logic. The conples latched near the midpoint of each baud (bit time). Nortrol registers and control logic determine the data format, mally, the position of the samples within the baud is mode of operation, clock source, and type of parity used. determined automatically, but software can override the auThe error detection circuit generates parity bits and checks tomatic selection by setting the USMD bit in the UMDSL2 for parity, framing, and overrun errors. register and programming the USPOS register. The Flow Control Logic block provides the capability for Serial data input on the RXD pin is shifted into the RSFT hardware handshaking between the UART and a peripheral register. On receiving the complete character, the contents device. When the peripheral device needs to stop the flow The Transmitter and Receiver blocks both contain extensions for 9-bit data transfers, as required by the 9-bit and loopback operating modes. www.national.com 114 Transmitter TXD Baud Clock RTS Flow Control Logic System Clock Internal Bus CTS Control and Error Detection Baud Rate Generator Parity Generator/Checker Baud Clock Receiver RXD DS163 Figure 41. 16 1 2 3 4 5 6 UART Block Diagram 7 8 9 Sample 10 11 12 13 14 15 1 2 1 Sample DATA (LSB) STARTBIT 16 16 3 4 5 6 7 8 9 10 11 12 13 14 15 16 1 Sample DATABIT DS061 Figure 42. 19.2.2 UART Asynchronous Communication Attention Mode The Attention mode is available for networking this device with other processors. This mode requires the 9-bit data format with no parity. The number of start bits and number of stop bits are programmable. In this mode, two types of 9-bit characters are sent on the network: address characters consisting of 8 address bits and a 1 in the ninth bit position and data characters consisting of 8 data bits and a 0 in the ninth bit position. While in Attention mode, the UART receiver monitors the communication flow but ignores all characters until an address character is received. On receiving an address char- acter, the contents of the receive shift register are copied to the receive buffer. The URBF bit is set and an interrupt (if enabled) is generated. The UATN bit is automatically cleared, and the UART begins receiving all subsequent characters. Software must examine the contents of the URBUF register and respond by accepting the subsequent characters (by leaving the UATN bit reset) or waiting for the next address character (by setting the UATN bit again). The operation of the UART transmitter is not affected by the selection of this mode. The value of the ninth bit to be transmitted is programmed by setting or clearing the UXB9 bit in 115 www.national.com CP3BT10 of the RSFT register are copied into the URBUF register from the URBUF register. The RSFT register is not software and the Receive Buffer Full bit (URBF) is set. The URBF bit accessible. is automatically reset when software reads the character CP3BT10 the UART Frame Select register. The value of the ninth bit received is read from URB9 in the UART Status Register. 19.2.3 the control registers, called UXB9 and URB9. Parity is not generated or verified in this mode. Diagnostic Mode The Diagnostic mode is available for testing of the UART. In this mode, the TXD and RXD pins are internally connected together, and data shifted out of the transmit shift register is immediately transferred to the receive shift register. This mode supports only the 9-bit data format with no parity. The number of start and stop bits is programmable. 19.2.4 3 Start Bit 9-Bit Data 3a Start Bit 9-Bit Data 1S 2S DS065 Frame Format Selection Figure 45. 9-bit Data Frame Options The format shown in Figure 43 consists of a start bit, seven 19.2.5 Baud Rate Generator data bits (excluding parity), and one or two stop bits. If parity bit generation is enabled by setting the UPEN bit, a parity bit The Baud Rate Generator creates the basic baud clock from is generated and transmitted following the seven data bits. the System Clock. The System Clock is passed through a two-stage divider chain consisting of a 5-bit baud rate prescaler (UPSC) and an 11-bit baud rate divisor (UDIV). Start 1 Bit 7-Bit Data 1a Start Bit 7-Bit Data 1b Start Bit 7-Bit Data 1c Start Bit 7-Bit Data 1S The relationship between the 5-bit prescaler select (UPSC) setting and the prescaler factors is shown in Table 44. Table 44 Prescaler Factors 2S PA PA 2S DS063 Figure 43. 7-Bit Data Frame Options The format shown in Figure 44 consists of one start bit, eight data bits (excluding parity), and one or two stop bits. If parity bit generation is enabled by setting the UPEN bit, a parity bit is generated and transmitted following the eight data bits. 2 Start Bit 2a Start Bit 2b Start Bit 8-Bit Data PA 2c Start Bit 8-Bit Data PA 8-Bit Data 1S 8-Bit Data 2S 1S 2S DS064 Figure 44. 8-Bit Data Frame Options The format shown in Figure 45 consists of one start bit, nine data bits, and one or two stop bits. This format also supports the UART attention feature. When operating in this format, all eight bits of UTBUF and URBUF are used for data. The ninth data bit is transmitted and received using two bits in www.national.com Prescaler Select Prescaler Factor 00000 No clock 00001 1 00010 1.5 00011 2 00100 2.5 00101 3 00110 3.5 00111 4 01000 4.5 01001 5 01010 5.5 01011 6 01100 6.5 01101 7 01110 7.5 01111 8 10000 8.5 10001 9 10010 9.5 10011 10 10100 10.5 10101 11 10110 11.5 10111 12 11000 12.5 11001 13 1S 116 Prescaler Select Prescaler Factor 11010 13.5 11011 14 11100 14.5 11101 15 11110 15.5 11111 16 SYS_CLKBR = ----------------------------(O × N × P) where BR is the baud rate, SYS_CLK is the System Clock frequency, O is the oversample rate, N is the value of the baud rate divisor + 1, and P is the prescaler divide factor selected by the value in the UPSR register. 19.2.6 The UART is capable of generating interrupts on: A prescaler factor of zero corresponds to “no clock.” The “no clock” condition is the UART power down mode, in which the UART clock is turned off to reduce power consumption. Software must select the “no clock” condition before entering a new baud rate. Otherwise, it could cause incorrect data to be received or transmitted. Receive Buffer Full Receive Error Transmit Buffer Empty Figure 46 shows a diagram of the interrupt sources and associated enable bits. UEEI UFE UDOE Interrupts UERR RX Interrupt UPE UERI URBF UETI TX Interrupt UTBE UEFCI FC Interrupt UDCTS DS066 Figure 46. UART Interrupts The interrupts can be individually enabled or disabled using the Enable Transmit Interrupt (UETI), Enable Receive Interrupt (UERI), and Enable Receive Error Interrupt (UEER) bits in the UICTRL register. bit or read the UICTRL register (which clears the UDCTS bit). In addition to the dedicated inputs to the ICU for UART interrupts, the UART receive (RXD) and Clear To Send (CTS) A transmit interrupt is generated when both the UTBE and signals are inputs to the MIWU (see Section 13.0), which UETI bits are set. To remove this interrupt, software must ei- can be programmed to generate edge-triggered interrupts. ther disable the interrupt by clearing the UETI bit or write to 19.2.7 DMA Support the UTBUF register (which clears the UTBE bit). The UART can operate with one or two DMA channels. Two A receive interrupt is generated on these conditions: DMA channels must be used for processor-independent Both the URBF and UERI bits are set. To remove this in- full-duplex operation. Both receive and transmit DMA can terrupt, software must either disable the interrupt by be enabled simultaneously. clearing the UERI bit or read from the URBUF register If transmit DMA is enabled (the UETD bit is set), the UART (which clears the URBF bit). generates a DMA request when the UTBE bit changes state Both the UERR and the UEEI bits are set. To remove this from clear to set. Enabling transmit DMA automatically disinterrupt, software must either disable the interrupt by ables transmit interrupts, without regard to the state of the clearing the UEEI bit or read the USTAT register (which UETI bit. clears the UERR bit). If receive DMA is enabled (the UERD bit is set), the UART A flow control interrupt is generated when both the UDCTS generates a DMA request when the URBF bit changes state and the UEFCI bits are set. To remove this interrupt, softfrom clear to set. Enabling receive DMA automatically disware must either disable the interrupt by clearing the UEFCI 117 www.national.com CP3BT10 In asynchronous mode, the baud rate is calculated by: Table 44 Prescaler Factors (Continued) CP3BT10 ables receive interrupts, without regard to the state of the UERI bit. However, receive error interrupts should be enabled (the UEEI bit is set) to allow detection of receive errors when DMA is used. 19.2.8 19.3.1 UART Receive Data Buffer (URBUF) The URBUF register is a byte-wide, read/write register used to receive each data byte. Break Generation and Detection 7 0 A line break is generated when the UBRK bit is set in the UMDSL1 register. The TXD line remains low until the program resets the UBRK bit. URBUF A line break is detected if RXD remains low for 10 bit times 19.3.2 UART Transmit Data Buffer (UTBUF) or longer after a missing stop bit is detected. The UTBUF register is a byte-wide, read/write register used to transmit each data byte. 19.2.9 Parity Generation and Detection Parity is only generated or checked with the 7-bit and 8-bit 7 0 data formats. It is not generated or checked in the diagnostic loopback mode, the attention mode, or in normal mode with UTBUF the 9-bit data format. Parity generation and checking are enabled and disabled using the PEN bit in the UFRS register. The UPSEL bits in the UFRS register are used to select 19.3.3 UART Baud Rate Prescaler (UPSR) odd, even, or no parity. The UPSR register is a byte-wide, read/write register that contains the 5-bit clock prescaler and the upper three bits of 19.3 UART REGISTERS the baud rate divisor. This register is cleared upon reset. Software interacts with the UART by accessing the UART The register format is shown below. registers. There are eight registers, as listed in Table 45. Table 45 UART Registers Name Address Description URBUF FF FE42h UART Receive Data Buffer UTBUF FF FE40h UART Transmit Data Buffer UPSR FF FE4Eh UART Baud Rate Prescaler UBAUD FF FE4Ch UART Baud Rate Divisor UFRS FF FE48h UART Frame Select Register UMDSL1 FF FE4Ah UART Mode Select Register 1 USTAT FF FE46h UART Status Register UICTRL FF FE44h UART Interrupt Control Register UOVR FF FE50h UART Oversample Rate Register UMDSL2 FF FE52h UART Mode Select Register 2 USPOS FF FE54h UART Sample Position Register www.national.com 7 3 UPSC UPSC UDIV10:8 19.3.4 2 0 UDIV10:8 The Prescaler field specifies the prescaler value used for dividing the System Clock in the first stage of the two-stage divider chain. For the prescaler factors corresponding to each 5bit value, see Table 44. The Baud Rate Divisor field holds the three most significant bits (bits 10, 9, and 8) of the UART baud rate divisor used in the second stage of the two-stage divider chain. The remaining bits of the baud rate divisor are held in the UBAUD register. UART Baud Rate Divisor (UBAUD) The UBAUD register is a byte-wide, read/write register that contains the lower eight bits of the baud rate divisor. The register contents are unknown at power-up and are left unchanged by a reset operation. The register format is shown below. 7 0 UDIV7:0 UDIV7:0 118 The Baud Rate Divisor field holds the eight lowest-order bits of the UART baud rate divisor used in the second stage of the two-stage divider chain. The three most significant bits are held in the UPSR register. The divisor value used is (UDIV[10:0] + 1). UART Frame Select Register (UFRS) 19.3.6 The UFRS register is a byte-wide, read/write register that controls the frame format, including the number of data bits, number of stop bits, and parity type. This register is cleared upon reset. The register format is shown below. 7 6 Reserved UPEN 5 4 UPSEL 3 2 UXB9 USTP 1 0 UART Mode Select Register 1 (UMDSL1) The UMDSL1 register is a byte-wide, read/write register that selects the clock source, synchronization mode, attention mode, and line break generation. This register is cleared at reset. When software writes to this register, the reserved bits must be written with 0 for proper operation. The register format is shown below. UCHAR 7 6 5 4 3 2 1 URTS UFCE UERD UETD Res. UBRK UATN UCHAR USTP UXB9 UPSEL UPEN The Character Frame Format field selects the number of data bits per frame, not including the parity bit, as follows: 00 – 8 data bits per frame. 01 – 7 data bits per frame. 10 – 9 data bits per frame. 11 – Loop-back mode, 9 data bits per frame. The Stop Bits bit specifies the number of stop bits transmitted in each frame. If this bit is 0, one stop bit is transmitted. If this bit is 1, two stop bits are transmitted. 0 – One stop bit per frame. 1 – Two stop bits per frame. The Transmit 9th Data Bit holds the value of the ninth data bit, either 0 or 1, transmitted when the UART is configured to transmit nine data bits per frame. It has no effect when the UART is configured to transmit seven or eight data bits per frame. The Parity Select field selects the treatment of the parity bit. When the UART is configured to transmit nine data bits per frame, the parity bit is omitted and the UPSEL field is ignored. 00 – Odd parity. 01 – Even parity. 10 – No parity, transmit 1 (mark). 11 – No parity, transmit 0 (space). The Parity Enable bit enables or disables parity generation and parity checking. When the UART is configured to transmit nine data bits per frame, there is no parity bit and the UPEN bit is ignored. 0 – Parity generation and checking disabled. 1 – Parity generation and checking enabled. UATN UBRK UETD UERD UFCE URTS 119 0 Res. The Attention Mode bit is used to enable Attention mode. When set, this bit selects the attention mode of operation for the UART. When clear, the attention mode is disabled. The hardware clears this bit after an address frame is received. An address frame is a 9-bit character with a 1 in the ninth bit position. 0 – Attention mode disabled. 1 – Attention mode enabled. The Force Transmission Break bit is used to force the TXD output low. Setting this bit to 1 causes the TXD pin to go low. TXD remains low until the UBRK bit is cleared by software. 0 – Normal operation. 1 – TXD pin forced low. The Enable Transmit DMA bit controls whether DMA is used for UART transmit operations. Enabling transmit DMA automatically disables transmit interrupts, without regard to the state of the UETI bit. 0 – Transmit DMA disabled. 1 – Transmit DMA enabled. The Enable Receive DMA bit controls whether DMA is used for UART receive operations. Enabling receive DMA automatically disables receive interrupts, without regard to the state of the UERI bit. Receive error interrupts are unaffected by the UERD bit. 0 – Receive DMA disabled. 1 – Receive DMA enabled. The Flow Control Enable bit controls whether flow control interrupts are enabled. 0 – Flow control interrupts disabled. 1 – Flow control interrupts enabled. The Ready To Send bit directly controls the state of the RTS output. 0 – RTS output is high. 1 – RTS output is low. www.national.com CP3BT10 19.3.5 CP3BT10 19.3.7 UART Status Register (USTAT) UXMIP The USTAT register is a byte-wide, read-only register that contains the receive and transmit status bits. This register is cleared upon reset. Any attempt by software to write to this register is ignored. The register format is shown below. 7 Res. UPE UFE UDOE UERR UBKD URB9 6 5 4 3 2 1 0 UXMIP URB9 UBKD UERR UDOE UFE UPE 19.3.8 The Transmit In Progress bit indicates when the UART is transmitting. The hardware sets this bit when the UART is transmitting data and clears the bit at the end of the last frame bit. 0 – UART is not transmitting. 1 – UART is transmitting. UART Interrupt Control Register (UICTRL) The UICTRL register is a byte-wide register that contains the receive and transmit interrupt status bits (read-only bits) The Parity Error bit indicates whether a parity and the interrupt enable bits (read/write bits). The register is error is detected within a received character. initialized to 01h at reset. The register format is shown beThis bit is automatically cleared by the hard- low. ware when the USTAT register is read. 0 – No parity error occurred. 7 6 5 4 3 2 1 0 1 – Parity error occurred. UEEI UERI UETI UEFCI UCTS UDCTS URBF UTBE The Framing Error bit indicates whether the UART fails to receive a valid stop bit at the end of a frame. This bit is automatically cleared by UTBE The Transmit Buffer Empty bit is set by hardthe hardware when the USTAT register is ware when the UART transfers data from the read. UTBUF register to the transmit shift register 0 – No framing error occurred. for transmission. It is automatically cleared by 1 – Framing error occurred. the hardware on the next write to the UTBUF The Data Overrun Error bit is set when a new register. character is received and transferred to the 0 – Transmit buffer is loaded. URBUF register before software has read the 1 – Transmit buffer is empty. previous character from the URBUF register. URBF The Receive Buffer Full bit is set by hardware This bit is automatically cleared by the hardwhen the UART has received a complete data ware when the USTAT register is read. frame and has transferred the data from the 0 – No receive overrun error occurred. receive shift register to the URBUF register. It 1 – Receive overrun error occurred. is automatically cleared by the hardware The Error Status bit indicates when a parity, when the URBUF register is read. framing, or overrun error occurs (any time that 0 – Receive buffer is empty. the UPE, UFE, or UDOE bit is set). It is auto1 – Receive buffer is loaded. matically cleared by the hardware when the UDCTS The Delta Clear To Send bit indicates whether UPE, UFE, and UDOE bits are all 0. the CTS input has changed state since the 0 – No receive error occurred. CPU last read this register. 1 – Receive error occurred. 0 – No change since last read. The Break Detect bit indicates when a line 1 – State has changed since last read. break condition occurs. This condition is deUCTS The Clear To Send bit indicates the state on tected if RXD remains low for at least ten bit the CTS input. times after a missing stop bit has been detect0 – CTS input is high. ed at the end of a frame. The hardware auto1 – CTS input is low. matically clears the UBKD bit upon read of the UEFCI The Enable Flow Control Interrupt bit controls USTAT register, but only if the break condition whether a flow control interrupt is generated on RXD no longer exists. If reading the USTAT when the UDCTS bit changes from clear to register does not clear the UBKD bit because set. the break is still actively driven on the line, the 0 – Flow control interrupt disabled. hardware clears the bit as soon as the break 1 – Flow control interrupt enabled. condition no longer exists (when the RXD inUETI The Enable Transmitter Interrupt bit, when put returns to a high level). set, enables generation of an interrupt when 0 – No break condition occurred. the hardware sets the UTBE bit. 1 – Break condition occurred. 0 – Transmit buffer empty interrupt disabled. The Received 9th Data Bit holds the ninth 1 – Transmit buffer empty interrupt enabled. data bit, when the UART is configured to opUERI The Enable Receiver Interrupt bit, when set, erate in the 9-bit data format. enables generation of an interrupt when the hardware sets the URBF bit. 0 – Receive buffer full interrupt disabled. 1 – Receive buffer full interrupt enabled. www.national.com 120 19.3.9 The Enable Receive Error Interrupt bit, when set, enables generation of an interrupt when the hardware sets the UERR bit in the USTAT register. 0 – Receive error interrupt disabled. 1 – Receive error interrupt enabled. 19.3.11 UART Sample Position Register (USPOS) The USPOS register is a byte-wide, read/write register that specifies the sample position when the USMD bit in the UMDSL2 register is set. At reset, the USPOS register is initialized to 06h. The register format is shown below. UART Oversample Rate Register (UOVR) 7 The UOVR register is a byte-wide, read/write register that specifies the oversample rate. At reset, the UOVR register is cleared. The register format is shown below. 4 Reserved UOVSR 3 0 UOVSR The Oversampling Rate field specifies the oversampling rate, as given in the following table. UOVSR3:0 Oversampling Rate 0000–0110 16 0111 7 1000 8 1001 0 USAMP The Sample Position field specifies the oversample clock period at which to take the first of three samples for sensing the value of data bits. The clocks are numbered starting at 0 and may range up to 15 for 16× oversampling. The maximum value for this field is (oversampling rate - 3). The table below shows the clock period at which each of the three samples is taken, when automatic sampling is enabled (UMDSL2.USMD = 0). Sample Position Oversampling Rate 1 2 3 7 2 3 4 9 8 2 3 4 1010 10 9 3 4 5 1011 11 10 3 4 5 1100 12 11 4 5 6 1101 13 12 4 5 6 1110 14 13 5 6 7 1111 15 14 5 6 7 15 6 7 8 16 6 7 8 19.3.10 UART Mode Select Register 2 (UMDSL2) The UMDSL2 register is a byte-wide, read/write register that controls the sample mode used to recover asynchronous data. At reset, the UOVR register is cleared. The register format is shown below. 7 1 Reserved USMD 3 Reserved USAMP 7 4 0 The USAMP field may be used to override the automatic selection, to choose any other clock period at which to start taking the three samples. USMD The USMD bit controls the sample mode for asynchronous transmission. 0 – UART determines the sample position automatically. 1 – The USPOS register determines the sample position. 121 www.national.com CP3BT10 UEEI CP3BT10 19.4 BAUD RATE CALCULATIONS The UART baud rate is determined by the System Clock frequency and the values in the UOVR, UPSR, and UBAUD registers. Unless the System Clock is an exact multiple of the baud rate, there will be a small amount of error in the resulting baud rate. The equation to calculate the baud rate is: SYS_CLKBR = ----------------------------(O × N × P) The N × P term is then divided by each Prescaler Factor from Table 44 to obtain a value closest to an integer. The factor for this example is 6.5. N = 32.552 ------------------ = 5.008 (N = 5) 6.5 The baud rate register is programmed with a baud rate divisor of 4 (N = baud rate divisor + 1). This produces a baud clock of: where BR is the baud rate, SYS_CLK is the System Clock, O is the oversample rate, N is the baud rate divisor + 1, and P is the prescaler divisor selected by the UPSR register. Assuming a System Clock of 5 MHz, a desired baud rate of 9600, and an oversample rate of 16, the N × P term according to the equation above is: 6 ( 5 ×10 ) - = 32.552 N × P = -----------------------------( 16 × 9600 ) 6 ( 5 ×10 ) = 9615.385 BR = ----------------------------------( 16 × 5 × 6.5 ) 9615.385 – 9600 )- = 0.16 %error = (-----------------------------------------------9600 Note that the percent error is much lower than would be possible without the non-integer prescaler factor. Error greater than 3% is marginal and may result in unreliable operation. Refer to Table 46 below for more examples. Table 46 Baud Rate Programming Baud Rate SYS_CLK = 48 MHz SYS_CLK = 24 MHz SYS_CLK = 12 MHz SYS_CLK = 10 MHz O N P %err O N P %err O N P %err O N P %err 300 16 2000 5.0 0.00 16 2000 2.5 0.00 16 1250 2.0 0.00 13 1282 2.0 0.00 600 16 2000 2.5 0.00 16 1250 2.0 0.00 16 1250 1.0 0.00 13 1282 1.0 0.00 1200 16 1250 2.0 0.00 16 1250 1.0 0.00 16 625 1.0 0.00 13 641 1.0 0.00 1800 7 401 9.5 0.00 8 1111 1.5 0.01 12 101 5.5 0.01 12 463 1.0 0.01 2000 16 1500 1.0 0.00 16 750 1.0 0.00 16 250 1.5 0.00 16 125 2.5 0.00 2400 16 1250 1.0 0.00 16 625 1.0 0.00 16 125 2.5 0.00 9 463 1.0 0.01 3600 8 1111 1.5 0.01 12 101 5.5 0.01 11 202 1.5 0.01 11 101 2.5 0.01 4800 16 625 1.0 0.00 16 125 2.5 0.00 10 250 1.0 0.00 7 119 2.5 0.04 7200 12 101 5.5 0.01 11 303 1.0 0.01 11 101 1.5 0.01 10 139 1.0 0.08 9600 16 125 2.5 0.00 10 250 1.0 0.00 10 125 1.0 0.00 7 149 1.0 0.13 14400 11 202 1.5 0.01 11 101 1.5 0.01 14 17 3.5 0.04 14 33 1.5 0.21 19200 10 250 1.0 0.00 10 125 1.0 0.00 10 25 2.5 0.00 16 13 2.5 0.16 38400 10 125 1.0 0.00 10 25 2.5 0.00 16 13 1.5 0.16 8 13 2.5 0.16 56000 7 49 2.5 0.04 13 33 1.0 0.10 13 11 1.5 0.10 7 17 1.5 0.04 115200 7 17 3.5 0.04 13 16 1.0 0.16 13 8 1.0 0.16 7 5 2.5 0.79 128000 15 25 1.0 0.00 15 5 2.5 0.00 11 1 8.5 0.27 12 1 6.5 0.16 230400 13 16 1.0 0.16 13 8 1.0 0.16 13 4 1.0 0.16 11 4 1.0 1.36 345600 9 1 15.5 0.44 10 7 1.0 0.79 10 1 3.5 0.79 460800 13 8 1.0 0.16 13 4 1.0 0.16 13 2 1.0 0.16 11 2 1.0 1.36 576000 8 7 1.5 0.79 12 1 3.5 0.79 14 1 1.5 0.79 7 1 2.5 0.79 691200 10 7 1.0 0.79 10 1 3.5 0.79 7 1 2.5 0.79 806400 7 1 8.5 0.04 15 2 1.0 0.79 10 1 1.5 0.79 921600 13 4 1.0 0.16 13 2 1.0 0.16 13 1 1.0 0.16 1105920 11 4 1.0 1.36 11 2 1.0 1.36 9 1 1.0 0.47 1382400 10 1 3.5 0.79 7 1 2.5 0.79 1536000 9 1 3.5 0.79 8 2 1.0 2.34 www.national.com 122 SYS_CLK = 8 MHz SYS_CLK = 6 MHz SYS_CLK = 5 MHz SYS_CLK = 4 MHz Baud Rate O N P %err O N P %err O N P %err O N P %err 300 7 401 9.5 0.00 16 1250 1.0 0.00 11 202 7.5 0.01 12 202 5.5 0.01 600 12 1111 1.0 0.01 16 625 1.0 0.00 11 101 7.5 0.01 12 101 5.5 0.01 1200 12 101 5.5 0.01 16 125 2.5 0.00 10 119 3.5 0.04 11 202 1.5 0.01 1800 8 101 5.5 0.01 11 303 1.0 0.01 11 101 2.5 0.01 11 202 1.0 0.01 2000 16 250 1.0 0.00 16 125 1.5 0.00 10 250 1.0 0.00 16 125 1.0 0.00 2400 11 303 1.0 0.01 10 250 1.0 0.00 7 119 2.5 0.04 11 101 1.5 0.01 3600 11 202 1.0 0.01 11 101 1.5 0.01 10 139 1.0 0.08 11 101 1.0 0.01 4800 11 101 1.5 0.01 10 125 1.0 0.00 7 149 1.0 0.13 14 17 3.5 0.04 7200 11 101 1.0 0.01 14 17 3.5 0.04 14 33 1.5 0.21 15 37 1.0 0.10 9600 14 17 3.5 0.04 10 25 2.5 0.00 16 13 2.5 0.16 7 17 3.5 0.04 14400 15 37 1.0 0.10 7 17 3.5 0.04 7 33 1.5 0.21 9 31 1.0 0.44 19200 7 17 3.5 0.04 16 13 1.5 0.16 8 13 2.5 0.16 16 13 1.0 0.16 38400 16 13 1.0 0.16 8 13 1.5 0.16 13 10 1.0 0.16 16 1 6.5 0.16 56000 13 11 1.0 0.10 9 12 1.0 0.79 15 6 1.0 0.79 13 1 5.5 0.10 115200 10 7 1.0 0.79 13 4 1.0 0.16 11 4 1.0 1.36 10 1 3.5 0.79 128000 9 7 1.0 0.79 16 3 1.0 2.34 13 3 1.0 0.16 9 1 3.5 0.79 230400 10 1 3.5 0.79 13 2 1.0 0.16 11 2 1.0 1.36 7 1 2.5 0.79 345600 15 1 1.5 2.88 7 1 2.5 0.79 460800 7 1 2.5 0.79 13 1 1.0 0.16 576000 7 2 1.0 0.79 7 1 1.5 0.79 SYS_CLK = 3 MHz SYS_CLK = 2 MHz SYS_CLK = 1 MHz SYS_CLK = 500 kHz Baud Rate O N P %err O N P %err O N P %err O N P %err 300 16 250 2.5 0.00 12 101 5.5 0.01 11 202 1.5 0.01 11 101 1.5 0.01 600 16 125 2.5 0.00 11 202 1.5 0.01 11 101 1.5 0.01 14 17 3.5 0.04 1200 10 250 1.0 0.00 11 101 1.5 0.01 14 17 3.5 0.04 7 17 3.5 0.04 1800 11 101 1.5 0.01 11 101 1.0 0.01 15 37 1.0 0.10 9 31 1.0 0.44 2000 15 100 1.0 0.00 16 25 2.5 0.00 10 50 1.0 0.00 10 25 1.0 0.00 2400 10 125 1.0 0.00 14 17 3.5 0.04 7 17 3.5 0.04 16 13 1.0 0.16 3600 14 17 3.5 0.04 15 37 1.0 0.10 9 31 1.0 0.44 9 1 15.5 0.44 4800 10 25 2.5 0.00 7 17 3.5 0.04 16 13 1.0 0.16 16 1 6.5 0.16 7200 7 17 3.5 0.04 9 31 1.0 0.44 9 1 15.5 0.44 10 7 1.0 0.79 9600 16 13 1.5 0.16 16 13 1.0 0.16 16 1 6.5 0.16 8 1 6.5 0.16 14400 13 16 1.0 0.16 9 1 15.5 0.44 10 7 1.0 0.79 10 1 3.5 0.79 19200 8 13 1.5 0.16 16 1 6.5 0.16 8 1 6.5 0.16 13 2 1.0 0.16 38400 13 6 1.0 0.16 8 1 6.5 0.16 13 2 1.0 0.16 13 1 1.0 0.16 56000 9 6 1.0 0.79 9 4 1.0 0.79 9 2 1.0 0.79 115200 13 2 1.0 0.16 7 1 2.5 0.79 128000 16 1 1.5 2.34 8 2 1.0 2.34 230400 13 1 1.0 0.16 123 www.national.com CP3BT10 Table 47 Baud Rate Programming CP3BT10 20.0 Microwire/SPI Interface Microwire/Plus is a synchronous serial communications protocol, originally implemented in National Semiconductor's COP8® and HPC families of microcontrollers to minimize the number of connections, and therefore the cost, of communicating with peripherals. The CP3BT10 has an enhanced Microwire/SPI interface module (MWSPI) that can communicate with all peripherals that conform to Microwire or Serial Peripheral Interface (SPI) specifications. This enhanced Microwire interface is capable of operating as either a master or slave and in 8- or 16-bit mode. Figure 47 shows a typical enhanced Microwire interface application. MWCS GPIO I/O Lines Master DO CS CS CS CS 8-Bit A/D 1K Bit EEPROM LCD Display Driver VF Display Driver SK DI DO SK DI SK DI MDIDO MDODI MDODI MSK Figure 47. Programmable operation as a Master or Slave Programmable shift-clock frequency (master only) Programmable 8- or 16-bit mode of operation 8- or 16-bit serial I/O data shift register Two modes of clocking data Serial clock can be low or high when idle 16-bit read buffer Busy bit, Read Buffer Full bit, and Overrun bit for polling and as interrupt sources Supports multiple masters Maximum bit rate of 10M bits/second (master mode) 5M bits/second (slave mode) at 20 MHz System Clock Supports very low-end slaves with the Slave Ready output Echo back enable/disable (Slave only) 20.1 The three-wire system includes: the serial data in signal (MDIDO for master mode, MDODI for slave mode), the serial data out signal (MDODI for master mode, MDIDO for slave mode), and the serial clock (MSK). In slave mode, an optional fourth signal (MWCS) may be used to enable the slave transmit. At any given time, only one slave can respond to the master. Each slave device has its own chip select signal (MWCS) for this purpose. Figure 48 shows a block diagram of the enhanced Microwire serial interface in the device. MICROWIRE OPERATION The Microwire interface allows several devices to be connected on one three-wire system. At any given time, one of these devices operates as the master while all other devices operate as slaves. The Microwire interface allows the device to operate either as a master or slave transferring 8- or 16bits of data. The master device supplies the synchronous clock (MSK) for the serial interface and initiates the data transfer. The slave devices respond by sending (or receiving) the requested data. Each slave device uses the master’s clock for serially shifting data out (or in), while the master shifts the data in (or out). www.national.com DS067 Microwire Interface The enhanced Microwire interface module includes the following features: I/O Lines DI MDIDO MSK SK Slave 124 Write Data Control + Status CP3BT10 Interrupt Request MWCS 16-BIt Read Buffer Write Data 8 8 MWDAT 16-BIt Shift Register Data Out Slave Master MDODI Slave Data In Master MDIDO MSK System Clock Clock Prescaler + Select Master Figure 48. 20.1.1 MSK Microwire Block Diagram Shifting The Microwire interface is a full duplex transmitter/receiver. A 16-bit shifter, which can be split into a low and high byte, is used for both transmitting and receiving. In 8-bit mode, only the lower 8-bits are used to transfer data. The transmitted data is shifted out through MDODI pin (master mode) or MDIDO pin (slave mode), starting with the most significant bit. At the same time, the received data is shifted in through MDIDO pin (master mode) or MDODI pin (slave mode), also starting with the most significant bit first. The shift in and shift out are controlled by the MSK clock. In each clock cycle of MSK, one bit of data is transmitted/received. The 16-bit shifter is accessible as the MWDAT register. Reading the MWDAT register returns the value in the read buffer. Writing to the MWDAT register updates the 16bit shifter. 20.1.2 DS068 Reading The enhanced Microwire interface implements a double buffer on read. As illustrated in Figure 48, the double read buffer consists of the 16-bit shifter and a buffer, called the read buffer. The “Receive Buffer Full” (RBF) bit indicates if the MWDAT register holds valid data. The OVR bit indicates that an overrun condition has occurred. 20.1.3 Writing The “Microwire Busy” (BSY) bit indicates whether the MWDAT register can be written. All write operations to the MWDAT register update the shifter while the data contained in the read buffer is not affected. Undefined results will occur if the MWDAT register is written to while the BSY bit is set. 20.1.4 Clocking Modes Two clocking modes are supported: the normal mode and the alternate mode. In the normal mode, the output data, which is transmitted on the MDODI pin (master mode) or the MDIDO pin (slave mode), is clocked out on the falling edge of the shift clock MSK. The input data, which is received via the MDIDO pin (master mode) or the MDODI pin (slave mode), is sampled on the rising edge of MSK. In the alternate mode, the output data is shifted out on the rising edge of MSK on the MDODI pin (master mode) or MDIDO pin (slave mode). The input data, which is received The 16-bit shifter loads the read buffer with new data when via MDIDO pin (master mode) or MDODI pin (slave mode), the data transfer sequence is completed and previous data is sampled on the falling edge of MSK. in the read buffer has been read. In master mode, an Overrun error occurs when the read buffer is full, the 16-bit shifter The clocking modes are selected with the MSKM bit. The SCIDL bit allows selection of the value of MSK when it is idle is full and a new data transfer sequence starts. (when there is no data being transferred). Various MSK When 8-bit mode is selected, the lower byte of the shift regclock frequencies can be programmed via the MCDV bits. ister is loaded into the lower byte of the read buffer and the Figures 27, 28, 29, and 30 show the data transfer timing for read buffer’s higher byte remains unchanged. 125 www.national.com CP3BT10 the normal and the alternate modes with the SCIDL bit equal to 0 and equal to 1. Note that when data is shifted out on MDODI (master mode) or MDIDO (slave mode) on the leading edge of the MSK clock, bit 14 (16-bit mode) is shifted out on the second leading edge of the MSK clock. When data are shifted out on MDODI (master mode) or MDIDO (slave mode) on the trailing edge of MSK, bit 14 (16-bit mode) is shifted out on the first trailing edge of MSK. 20.2 MASTER MODE In Master mode, the MSK pin is an output for the shift clock, MSK. When data is written to the (MWDAT register), eight or sixteen MSK clocks, depending on the mode selected, are generated to shift the 8 or 16 bits of data and then MSK goes idle again. The MSK idle state can be either high or low, depending on the SCIDL bit. End of Transfer MSK Shift Out Data Out MSB MSB - 1 MSB - 2 Bit 1 Bit 0 (LSB) MSB - 1 MSB - 2 Bit 1 Bit 0 (LSB) Sample Point Data In MSB DS069 Figure 49. Normal Mode (SCIDL = 0) End of Transfer MSK Shift Out MSB Data Out MSB - 1 MSB - 2 Bit 1 Bit 0 (LSB) MSB - 1 MSB - 2 Bit 1 Bit 0 (LSB) Sample Point MSB Data In DS070 Figure 50. Normal Mode (SCIDL = 1) End of Transfer MSK Shift Out Data Out MSB MSB - 1 MSB - 2 Bit 1 Bit 0 (LSB) MSB - 1 MSB - 2 Bit 1 Bit 0 (LSB) Sample Point Data In MSB DS071 Figure 51. Alternate Mode (SCIDL = 0) www.national.com 126 MSK Shift Out Data Out MSB MSB - 1 MSB - 2 Bit 1 Bit 0 (LSB) MSB - 1 MSB - 2 Bit 1 Bit 0 (LSB) Sample Point Data In MSB DS072 Figure 52. Alternate Mode (SCIDL = 1) 20.3 SLAVE MODE In Slave mode, the MSK pin is an input for the shift clock MSK. MDIDO is placed in TRI-STATE mode when MWCS is inactive. Data transfer is enabled when MWCS is active. Figure 53 illustrates the various interrupt capabilities of this module. EIO The slave starts driving MDIDO when MWCS is activated. The most significant bit (lower byte in 8-bit mode or upper byte in 16-bit mode) is output onto the MDIDO pin first. After eight or sixteen clocks (depending on the selected mode), the data transfer is completed. OVR = 1 EIR If a new shift process starts before MWDAT was written, i.e., while MWDAT does not contain any valid data, and the “Echo Enable” (ECHO) bit is set, the data received from MDODI is transmitted on MDIDO in addition to being shifted to MWDAT. If the ECHO bit is clear, the data transmitted on MDIDO is the data held in the MWDAT register, regardless of its validity. The master may negate the MWCS signal to synchronize the bit count between the master and the slave. In the case that the slave is the only slave in the system, MWCS can be tied to VSS. 20.5 20.4 INTERRUPT GENERATION MWSPI Interrupt RBF = 1 EIW BSY = 0 DS073 Figure 53. MWSPI Interrupts MICROWIRE INTERFACE REGISTERS Software interacts with the Microwire interface by accessing the Microwire registers. There are three such registers: An interrupt is generated in any of the following cases: Table 48 Microwire Interface Registers When the read buffer is full (RBF = 1) and the “Enable Interrupt for Read” bit is set (EIR = 1). Whenever the shifter is not busy, i.e. the BSY bit is clear (BSY = 0) and the “Enable Interrupt for Write” bit is set (EIW = 1). When an overrun condition occurs (OVR is set) and the “Enable Interrupt on Overrun” bit is set (MEIO = 1). This usage is restricted to master mode. In addition, MWCS is an input to the MIWU (see Section 13.0), which can be programmed to generate an edge-triggered interrupt. Name Address Description MWDAT FF FE60h Microwire Data Register MWCTL1 FF FE62h Microwire Control Register MWSTAT FF FE64h Microwire Status Register 20.5.1 Microwire Data Register (MWDAT) The MWDAT register is a word-wide, read/write register used to transmit and receive data through the MDODI and MDIDO pins. Figure 54 shows the hardware structure of the register. 127 www.national.com CP3BT10 End of Transfer CP3BT10 MWDAT Write Shifter (Low Byte) DIN Shifter (High Byte) 1 DOUT 0 Read Buffer (Low Byte) Read Buffer (High Byte) MOD Read DS074 Figure 54. 20.5.2 MWDAT Register Microwire Control Register (MWCTL1) MNS The MWCTL1 register is a word-wide, read/write register used to control the Microwire module. To avoid clock glitches, the MWEN bit must be clear while changing the states of any other bits in the register. At reset, all non-reserved bits are cleared. The register format is shown below. 7 6 5 4 SCM EIW EIR EIO 3 2 ECHO MOD 15 1 0 MNS MWEN 9 SCDV MWEN MOD 8 SCIDL ECHO The Microwire Enable bit controls whether the Microwire interface module is enabled. 0 – Microwire module disabled. 1 – Microwire module enabled. Clearing this bit disables the module, clears the status bits in the Microwire status register (the BSY, RBF, and OVR bits in MWSTAT), and places the Microwire interface pins in the states described below. Pin MSK State When Disabled Master – SCIDL Bit Slave – Input MWCS Input MDIDO Master – Input Slave – TRI-STATE MDODI Master – Known value Slave – Input www.national.com EIO 128 The Master/Slave Select bit controls whether the CP3BT10 is a master or slave. When clear, the device operates as a slave. When set, the device operates as the master. 0 – CP3BT10 is slave. 1 – CP3BT10 is master. The Mode Select bit controls whether 8- or 16bit mode is used. When clear, the device operates in 8-bit mode. When set, the device operates in 16-bit mode. This bit must only be changed when the module is disabled or idle (MWSTAT.BSY = 0). 0 – 8-bit mode. 1 – 16-bit mode. The Echo Back bit controls whether the echo back function is enabled in slave mode. This bit must be written only when the Microwire interface is idle (MWSTAT.BSY=0). The ECHO bit is ignored in master mode. The MWDAT register is valid from the time the register has been written until the end of the transfer. In the echo back mode, MDODI is transmitted (echoed back) on MDIDO if the MWDAT register does not contain any valid data. With the echo back function disabled, the data held in the MWDAT register is transmitted on MDIDO, whether or not the data is valid. 0 – Echo back disabled. 1 – Echo back enabled. The Enable Interrupt on Overrun bit enables or disables the overrun error interrupt. When set, an interrupt is generated when the Receive Overrun Error bit (MWSTAT.OVR) is set. Otherwise, no interrupt is generated when an overrun error occurs. This bit must only be enabled in master mode. 0 – Disable overrun error interrupts. 1 – Enable overrun error interrupts. EIW SCM SCIDL SCDV The Enable Interrupt for Read bit controls whether an interrupt is generated when the read buffer becomes full. When set, an interrupt is generated when the Read Buffer Full bit (MWSTAT.RBF) is set. Otherwise, no interrupt is generated when the read buffer is full. 0 – No read buffer full interrupt. 1 – Interrupt when read buffer becomes full. The Enable Interrupt for Write bit controls whether an interrupt is generated when the Busy bit (MWSTAT.BSY) is cleared, which indicates that a data transfer sequence has been completed and the read buffer is ready to receive the new data. Otherwise, no interrupt is generated when the Busy bit is cleared. 0 – No interrupt on data transfer complete. 1 – Interrupt on data transfer complete. The Shift Clock Mode bit selects between the normal clocking mode and the alternate clocking mode. In the normal mode, the output data is clocked out on the falling edge of MSK and the input data is sampled on the rising edge of MSK. In the alternate mode, the output data is clocked out on the rising edge of MSK and the input data is sampled on the falling edge of MSK. 0 – Normal clocking mode. 1 – Alternate clocking mode. The Shift Clock Idle bit controls the value of the MSK output when the Microwire module is idle. This bit must be changed only when the Microwire module is disabled (MWEN = 0) or when no bus transaction is in progress (MWSTAT.BSY = 0). 0 – MSK is low when idle. 1 – MSK is high when idle The Shift Clock Divider Value field specifies the divisor used for generating the MSK shift clock from the System Clock. The divisor is 2 × (MCDV[6:0] + 1). Valid values are 0000001b to 1111111b, so the division ratio may range from 3 to 256. This field is ignored in slave mode (MWCTL1.MMNS=0). 20.5.3 Microwire Status Register (MWSTAT) The MWSTAT register is a word-wide, read-only register that shows the current status of the Microwire interface module. At reset, all non-reserved bits are clear. The register format is shown below. 15 3 Reserved BSY RBF OVR 129 2 1 0 OVR RBF BSY The Busy bit, when set, indicates that the Microwire shifter is busy. In master mode, the BSY bit is set when the MWDAT register is written. In slave mode, the bit is set on the first leading edge of MSK when MWCS is asserted or when the MWDAT register is written, whichever occurs first. In both master and slave modes, this bit is cleared when the Microwire data transfer sequence is completed and the read buffer is ready to receive the new data; in other words, when the previous data held in the read buffer has already been read. If the previous data in the read buffer has not been read and new data has been received into the shift register, the BSY bit will not be cleared, as the transfer could not be completed because the contents of the shift register could not be transferred into the read buffer. 0 – Microwire shifter is not busy. 1 – Microwire shifter is busy. The Read Buffer Full bit, when set, indicates that the Microwire read buffer is full and ready to be read by software. It is set when the shifter loads the read buffer, which occurs upon completion of a transfer sequence if the read buffer is empty. The RBF bit is updated when the MWDAT register is read. At that time, the RBF bit is cleared if the shifter does not contain any new data (in other words, the shifter is not receiving data or has not yet received a full byte of data). The RBF bit remains set if the shifter already holds new data at the time that MWDAT is read. In that case, MWDAT is immediately reloaded with the new data and is ready to be read by software. 0 – Microwire read buffer is not full. 1 – Microwire read buffer is full. The Receive Overrun Error bit, when set in master mode, indicates that a receive overrun error has occurred. This error occurs when the read buffer is full, the 8-bit shifter is full, and a new data transfer sequence starts. This bit is undefined in slave mode. The OVR bit, once set, remains set until cleared by software. Software clears this bit by writing a 1 to its bit position. Writing a 0 to this bit position has no effect. No other bits in the MWSTAT register are affected by a write operation to the register. 0 – No receive overrun error has occurred. 1 – Receive overrun error has occurred. www.national.com CP3BT10 EIR CP3BT10 21.0 ACCESS.bus Interface The ACCESS.bus interface module (ACB) is a two-wire se- mand/control information and data using the synchronous rial interface compatible with the ACCESS.bus physical lay- serial clock. er. It permits easy interfacing to a wide range of low-cost memories and I/O devices, including: EEPROMs, SRAMs, timers, A/D converters, D/A converters, clock chips, and peSDA ripheral drivers. It is compatible with Intel’s SMBus and Philips’ I2C bus. The module can be configured as a bus master or slave, and can maintain bidirectional communications SCL with both multiple master and slave devices. This section presents an overview of the bus protocol, and its implementation by the module. Data Line Stable: Data Valid ACCESS.bus master and slave Supports polling and interrupt-controlled operation Generate a wake-up signal on detection of a Start Condition, while in power-down mode Optional internal pull-up on SDA and SCL pins Change of Data Allowed DS075 Figure 55. Bit Transfer Each data transaction is composed of a Start Condition, a number of byte transfers (programmed by software), and a Stop Condition to terminate the transaction. Each byte is 21.1 ACB PROTOCOL OVERVIEW transferred with the most significant bit first, and after each The ACCESS.bus protocol uses a two-wire interface for bi- byte, an Acknowledge signal must follow. directional communication between the devices connected At each clock cycle, the slave can stall the master while it to the bus. The two interface signals are the Serial Data Line handles the previous data, or prepares new data. This can (SDA) and the Serial Clock Line (SCL). These signals be performed for each bit transferred or on a byte boundary should be connected to the positive supply, through pull-up by the slave holding SCL low to extend the clock-low period. resistors, to keep the signals high when the bus is idle. Typically, slaves extend the first clock cycle of a transfer if a The ACCESS.bus protocol supports multiple master and slave transmitters and receivers. Each bus device has a unique address and can operate as a transmitter or a receiver (though some peripherals are only receivers). byte read has not yet been stored, or if the next byte to be transmitted is not yet ready. Some microcontrollers with limited hardware support for ACCESS.bus extend the access after each bit, to allow software time to handle this bit. During data transactions, the master device initiates the transaction, generates the clock signal, and terminates the transaction. For example, when the ACB initiates a data transaction with an ACCESS.bus peripheral, the ACB becomes the master. When the peripheral responds and transmits data to the ACB, their master/slave (data transaction initiator and clock generator) relationship is unchanged, even though their transmitter/receiver functions are reversed. Start and Stop 21.1.1 The ACCESS.bus master generates Start and Stop Conditions (control codes). After a Start Condition is generated, the bus is considered busy and it retains this status until a certain time after a Stop Condition is generated. A high-tolow transition of the data line (SDA) while the clock (SCL) is high indicates a Start Condition. A low-to-high transition of the SDA line while the SCL is high indicates a Stop Condition (Figure 56). Data Transactions One data bit is transferred during each clock period. Data is sampled during the high phase of the serial clock (SCL). Consequently, throughout the clock high phase, the data must remain stable (see Figure 55). Any change on the SDA signal during the high phase of the SCL clock and in the middle of a transaction aborts the current transaction. New data must be driven during the low phase of the SCL clock. This protocol permits a single data line to transfer both com- SDA SCL P S Start Condition Stop Condition DS076 Figure 56. Start and Stop Conditions In addition to the first Start Condition, a repeated Start Condition can be generated in the middle of a transaction. This allows another device to be accessed, or a change in the direction of the data transfer. www.national.com 130 Addressing Transfer Formats The Acknowledge Cycle consists of two signals: the acknowledge clock pulse the master sends with each byte transferred, and the acknowledge signal sent by the receiving device (Figure 57). Each device on the bus has a unique address. Before any data is transmitted, the master transmits the address of the slave being addressed. The slave device should send an acknowledge signal on the SDA signal, once it recognizes its address. Acknowledgment Signal from Receiver The address is the first seven bits after a Start Condition. The direction of the data transfer (R/W) depends on the bit sent after the address (the eighth bit). A low-to-high transition during a SCL high period indicates the Stop Condition, and ends the transaction (Figure 59). SDA MSB SCL 1 2 3-6 7 8 S Start Condition 9 ACK 1 2 3-8 9 ACK P Stop Condition Clock Line Held Low by Receiver While Interrupt is Serviced Byte Complete Interrupt Within Receiver SDA DS077 SCL 1-7 8 9 1-7 8 9 1-7 8 9 S Figure 57. ACCESS.bus Data Transaction P Address R/W ACK Data ACK Data ACK Start Stop The master generates the acknowledge clock pulse on the Condition Condition ninth clock pulse of the byte transfer. The transmitter releasDS079 es the SDA line (permits it to go high) to allow the receiver to send the acknowledge signal. The receiver must pull down the SDA line during the acknowledge clock pulse, which signals the correct reception of the last data byte, and Figure 59. A Complete ACCESS.bus Data Transaction its readiness to receive the next byte. Figure 58 illustrates When the address is sent, each device in the system comthe acknowledge cycle. pares this address with its own. If there is a match, the device considers itself addressed and sends an acknowledge Data Output signal. Depending upon the state of the R/W bit (1 = read, by Transmitter Transmitter Stays Off 0 = write), the device acts as a transmitter or a receiver. the Bus During the Acknowledgment Clock The ACCESS.bus protocol allows sending a general call address to all slaves connected to the bus. The first byte sent specifies the general call address (00h) and the second byte specifies the meaning of the general call (for example, “Write slave address by software only”). Those slaves that require the data acknowledge the call and become slave receivers; the other slaves ignore the call. Data Output by Receiver Acknowledgment Signal from Receiver SCL 1 S Start Condition 2 3-6 7 8 9 DS078 Arbitration on the Bus Figure 58. ACCESS.bus Acknowledge Cycle The master generates an acknowledge clock pulse after each byte transfer. The receiver sends an acknowledge signal after every byte received. There are two exceptions to the “acknowledge after every byte” rule. When the master is the receiver, it must indicate to the transmitter an end-of-data condition by not-acknowledging (“negative acknowledge”) the last byte clocked out of the slave. This “negative acknowledge” still includes the acknowledge clock pulse (generated by the master), but the SDA line is not pulled down. When the receiver is full, otherwise occupied, or a problem has occurred, it sends a negative acknowledge to indicate that it cannot accept additional data bytes. Arbitration is required when multiple master devices attempt to gain control of the bus simultaneously. Control of the bus is initially determined according to address bits and clock cycle. If the masters are trying to address the same bus device, data comparisons determine the outcome of this arbitration. In master mode, the device immediately aborts a transaction if the value sampled on the SDA lines differs from the value driven by the device. (Exceptions to this rule are SDA while receiving data; in these cases the lines may be driven low by the slave without causing an abort.) The SCL signal is monitored for clock synchronization and allows the slave to stall the bus. The actual clock period will be the one set by the master with the longest clock period or by the slave stall period. The clock high period is determined by the master with the shortest clock high period. When an abort occurs during the address transmission, the master that identifies the conflict should give up the bus, switch to slave mode, and continue to sample SDA to see if it is being addressed by the winning master on the ACCESS.bus. 131 www.national.com CP3BT10 Acknowledge Cycle CP3BT10 21.2 ACB FUNCTIONAL DESCRIPTION 4. If the requested direction is transmit, and the start transaction was completed successfully (i.e., neither the ACBST.NEGACK nor ACBST.BER bit is set, and no other master has accessed the device), the ACBST.SDAST bit is set to indicate that the module is waiting for service. 5. If the requested direction is receive, the start transaction was completed successfully, and the ACBCTL1.STASTRE bit is clear, the module starts receiving the first byte automatically. 6. Check that both the ACBST.BER and ACBST.NEGACK bits are clear. If the ACBCTL1.INTEN bit is set, an interrupt is generated when either the ACBST.BER or ACBST.NEGACK bit is set. The ACB module provides the physical layer for an ACCESS.bus compliant serial interface. The module is configurable as either a master or slave device. As a slave, the ACB module may issue a request to become the bus master. 21.2.1 Master Mode An ACCESS.bus transaction starts with a master device requesting bus mastership. It sends a Start Condition, followed by the address of the device it wants to access. If this transaction is successfully completed, software can assume that the device has become the bus master. For a device to become the bus master, software should perform the following steps: 1. Set the ACBCTL1.START bit, and configure the ACBCTL1.INTEN bit to the desired operation mode (Polling or Interrupt). This causes the ACB to issue a Start Condition on the ACCESS.bus, as soon as the ACCESS.bus is free (ACBCST.BB=0). It then stalls the bus by holding SCL low. 2. If a bus conflict is detected, (i.e., some other device pulls down the SCL signal before this device does), the ACBST.BER bit is set. 3. If there is no bus conflict, the ACBST.MASTER and ACBST.SDAST bits are set. 4. If the ACBCTL1.INTEN bit is set, and either the ACBST.BER bit or the ACBST.SDAST bit is set, an interrupt is sent to the ICU. Master Transmit After becoming the bus master, the device can start transmitting data on the ACCESS.bus. To transmit a byte, software must: 1. Check that the BER and NEGACK bits in the ACBST register are clear and the ACBST.SDAST bit is set. Also, if the ACBCTL1.STASTRE bit is set, check that the ACBST.STASTR bit is clear. 2. Write the data byte to be transmitted to the ACBSDA register. When the slave responds with a negative acknowledge, the ACBST.NEGACK bit is set and the ACBST.SDAST bit remains cleared. In this case, if the ACBCTL1.INTEN bit is set, an interrupt is sent to the core. Master Receive Sending the Address Byte After becoming the bus master, the device can start receivOnce this device is the active master of the ACCESS.bus ing data on the ACCESS.bus. To receive a byte, software (ACBST.MASTER = 1), it can send the address on the bus. must: The address should not be this device’s own address as specified in the ACBADDR.ADDR field if the ACBAD- 1. Check that the ACBST.SDAST bit is set and the ACBST.BER bit is clear. Also, if the ACBCTL1.STASTRE bit DR.SAEN bit is set or the ACBADDR2.ADDR field if the is set, check that the ACBST.STASTR bit is clear. ACBADDR2.SAEN bit is set, nor should it be the global call 2. Set the ACBCTL1.ACK bit, if the next byte is the last address if the ACBST.GCMTCH bit is set. byte that should be read. This causes a negative acTo send the address byte use the following sequence: knowledge to be sent. 1. Configure the ACBCTL1.INTEN bit according to the de- 3. Read the data byte from the ACBSDA register. sired operation mode. For a receive transaction where software wants only one byte of data, it should set the Master Stop ACBCTL1.ACK bit. If only an address needs to be sent, A Stop Condition may be issued only when this device is the set the ACBCTL1.STASTRE bit. active bus master (ACBST.MASTRER = 1). To end a trans2. Write the address byte (7-bit target device address), action, set the ACBCTL1.STOP bit before clearing the curand the direction bit, to the ACBSDA register. This rent stall bit (i.e., the ACBST.SDAST, ACBST.NEGACK, or causes the module to generate a transaction. At the ACBST.STASTR bit). This causes the module to send a end of this transaction, the acknowledge bit received is Stop Condition immediately, and clear the ACBCTL1.STOP copied to the ACBST.NEGACK bit. During the transac- bit. tion, the SDA and SCL signals are continuously checked for conflict with other devices. If a conflict is Master Bus Stall detected, the transaction is aborted, the ACBST.BER bit is set, and the ACBST.MASTER bit is cleared. 3. If the ACBCTL1.STASTRE bit is set, and the transaction was successfully completed (i.e., both the ACBST.BER and ACBST.NEGACK bits are cleared), the ACBST.STASTR bit is set. In this case, the ACB stalls any further ACCESS.bus operations (i.e., holds SCL low). If the ACBCTL1.INTE bit is set, it also sends an interrupt to the ICU. www.national.com The ACB module can stall the ACCESS.bus between transfers while waiting for the core’s response. The ACCESS.bus is stalled by holding the SCL signal low after the acknowledge cycle. Note that this is interpreted as the beginning of the following bus operation. Software must make sure that the next operation is prepared before the bit that causes the bus stall is cleared. 132 21.2.2 Slave Mode Negative acknowledge after sending a byte A slave device waits in Idle mode for a master to initiate a (ACBSTNEGACK = 1). bus transaction. Whenever the ACB is enabled, and it is not ACBST.SDAST bit is set. acting as a master (i.e., ACBST.MASTER = 0), it acts as a If the ACBCTL1.STASTRE bit is set, after a successful slave device. start (ACBST.STASTR = 1). Once a Start Condition on the bus is detected, this device checks whether the address sent by the current master Repeated Start matches either: A repeated start is performed when this device is already the bus master (ACBST.MASTER = 1). In this case, the AC- The ACBADDR.ADDR value if the ACBADDR.SAEN bit is set. CESS.bus is stalled and the ACB waits for the core handling due to: negative acknowledge (ACBST.NEGACK = 1), emp- The ACBADDR2.ADDR value if the ACBADDR2.SAEN bit is set. ty buffer (ACBST.SDAST = 1), or a stop-after-start (ACB The general call address if the ACBCTL1.GCM bit is set. ST.STASTR = 1). This match is checked even when the ACBST.MASTER bit For a repeated start: is set. If a bus conflict (on SDA or SCL) is detected, the 1. Set the ACBCTL1.START bit. ACBST.BER bit is set, the ACBST.MASTER bit is cleared, 2. In master receive mode, read the last data item from and this device continues to search the received message the ACBSDA register. for a match. If an address match, or a global match, is de3. Follow the address send sequence, as described in tected: “Sending the Address Byte” on page 132. 4. If the ACB was waiting for handling due to ACB- 1. This device asserts its data pin during the acknowledge cycle. ST.STASTR = 1, clear it only after writing the requested 2. The ACBCST.MATCH, ACBCST.MATCHAF (or address and direction to the ACBSDA register. ACBCST.GCMTCH if it is a global call address match, Master Error Detections or ACBCST.ARPMATCH if it is an ARP address), and ACBST.NMATCH in the ACBCST register are set. If the The ACB detects illegal Start or Stop Conditions (i.e., a ACBST.XMIT bit is set (i.e., slave transmit mode), the Start or Stop Condition within the data transfer, or the acACBST.SDAST bit is set to indicate that the buffer is knowledge cycle) and a conflict on the data lines of the ACempty. CESS.bus. If an illegal action is detected, the BER bit is set, and the MASTER mode is exited (the MASTER bit is 3. If the ACBCTL1.INTEN bit is set, an interrupt is generated if both the INTEN and NMINTE bits in the cleared). ACBCTL1 register are set. Bus Idle Error Recovery 4. Software then reads the ACBST.XMIT bit to identify the When a request to become the active bus master or a redirection requested by the master device. It clears the start operation fails, the ACBST.BER bit is set to indicate the ACBST.NMATCH bit so future byte transfers are identierror. In some cases, both this device and the other device fied as data bytes. may identify the failure and leave the bus idle. In this case, Slave Receive and Transmit the start sequence may not be completed and the ACSlave Receive and Transmit are performed after a match is CESS.bus may remain deadlocked. detected and the data transfer direction is identified. After a To recover from deadlock, use the following sequence: byte transfer, the ACB extends the acknowledge clock until 1. Clear the ACBST.BER and ACBCST.BB bits. software reads or writes the ACBSDA register. The receive 2. Wait for a time-out period to check that there is no other and transmit sequence are identical to those used in the active master on the bus (i.e., the ACBCST.BB bit re- master routine. mains clear). 3. Disable, and re-enable the ACB to put it in the non-ad- Slave Bus Stall dressed slave mode. When operating as a slave, this device stalls the AC4. At this point, some of the slaves may not identify the CESS.bus by extending the first clock cycle of a transaction bus error. To recover, the ACB becomes the bus master in the following cases: by issuing a Start Condition and sends an address — The ACBST.SDAST bit is set. field; then issue a Stop Condition to synchronize all the — The ACBST.NMATCH, and ACBCTL1.NMINTE bits slaves. are set. Slave Error Detections The ACB detects illegal Start and Stop Conditions on the ACCESS.bus (i.e., a Start or Stop Condition within the data transfer or the acknowledge cycle). When an illegal Start or Stop Condition is detected, the BER bit is set and the MATCH and GMATCH bits are cleared, causing the module to be an unaddressed slave. 133 www.national.com CP3BT10 The bits that can cause a stall in master mode are: CP3BT10 21.3 Power Down ACCESS.BUS INTERFACE REGISTERS When this device is in Power Save, Idle, or Halt mode, the The ACCESS.bus interface uses the registers listed in ACB module is not active but retains its status. If the ACB is Table 49. enabled (ACBCTL2.ENABLE = 1) on detection of a Start Table 49 ACCESS.bus Interface Registers Condition, a wake-up signal is issued to the MIWU module (see Section 13.0). Use this signal to switch this device to Name Address Description Active mode. The ACB module cannot check the address byte for a match following the start condition that caused the wake-up event for this device. The ACB responds with a negative acknowledge, and the device should resend both the Start Condition and the address after this device has had time to wake up. Check that the ACBCST.BUSY bit is inactive before entering Power Save, Idle, or Halt mode. This guarantees that the device does not acknowledge an address sent and stop responding later. 21.2.3 SDA and SCL Pins Configuration The SDA and SCL pins are driven as open-drain signals. For more information, see the I/O configuration section. ACBSDA FF FEC0h ACB Serial Data Register ACBST FF FEC2h ACB Status Register ACBCST FF FEC4h ACB Control Status Register ACBCTL1 FF FEC6h ACB Control Register 1 ACBCTL2 FF FECAh ACB Control Register 2 ACBCTL3 FF FECEh ACB Control Register 3 21.2.4 ACB Clock Frequency Configuration ACB Own Address The ACB module permits software to set the clock frequenACBADDR1 FF FEC8h Register 1 cy used for the ACCESS.bus clock. The clock is set by the ACBCTL2.SCLFRQ field. This field determines the SCL ACB Own Address ACBADDR2 FF FECCh clock period used by this device. This clock low period may Register 2 be extended by stall periods initiated by the ACB module or by another ACCESS.bus device. In case of a conflict with 21.3.1 ACB Serial Data Register (ACBSDA) another bus master, a shorter clock high period may be forced by the other bus master until the conflict is resolved. The ACBSDA register is a byte-wide, read/write shift register used to transmit and receive data. The most significant bit is transmitted (received) first and the least significant bit is transmitted (received) last. Reading or writing to the ACBSDA register is allowed when ACBST.SDAST is set; or for repeated starts after setting the START bit. An attempt to access the register in other cases produces unpredictable results. 7 0 DATA 21.3.2 ACB Status Register (ACBST) The ACBST register is a byte-wide, read-only register that maintains current ACB status. At reset, and when the module is disabled, ACBST is cleared. 7 6 5 4 3 2 1 0 SLVSTP SDAST BER NEGACK STASTR NMATCH MASTER XMIT XMIT www.national.com 134 The Direction Bit bit is set when the ACB module is currently in master/slave transmit mode. Otherwise it is cleared. 0 – Receive mode. 1 – Transmit mode. NMATCH STASTR NEGACK BER The Master bit indicates that the module is currently in master mode. It is set when a request for bus mastership succeeds. It is cleared upon arbitration loss (BER is set) or the recognition of a Stop Condition. 0 – Slave mode. 1 – Master mode. The New match bit is set when the address byte following a Start Condition, or repeated starts, causes a match or a global-call match. The NMATCH bit is cleared when written with 1. Writing 0 to NMATCH is ignored. If the ACBCTL1.INTEN bit is set, an interrupt is sent when this bit is set. 0 – No match. 1 – Match or global-call match. The Stall After Start bit is set by the successful completion of an address sending (i.e., a Start Condition sent without a bus error, or negative acknowledge), if the ACBCTL1.STASTRE bit is set. This bit is ignored in slave mode. When the STASTR bit is set, it stalls the bus by pulling down the SCL line, and suspends any other action on the bus (e.g., receives first byte in master receive mode). In addition, if the ACBCTL1.INTEN bit is set, it also sends an interrupt to the ICU. Writing 1 to the STASTR bit clears it. It is also cleared when the module is disabled. Writing 0 to the STASTR bit has no effect. 0 – No stall after start condition. 1 – Stall after successful start. The Negative Acknowledge bit is set by hardware when a transmission is not acknowledged on the ninth clock. (In this case, the SDAST bit is not set.) Writing 1 to NEGACK clears it. It is also cleared when the module is disabled. Writing 0 to the NEGACK bit is ignored. 0 – No transmission not acknowledged condition. 1 – Transmission not acknowledged. The Bus Error bit is set by the hardware when a Start or Stop Condition is detected during data transfer (i.e., Start or Stop Condition during the transfer of bits 2 through 8 and acknowledge cycle), or when an arbitration problem is detected. Writing 1 to the BER bit clears it. It is also cleared when the module is disabled. Writing 0 to the BER bit is ignored. 0 – No bus error occurred. 1 – Bus error occurred. SDAST SLVSTP 21.3.3 The SDA Status bit indicates that the SDA data register is waiting for data (transmit, as master or slave) or holds data that should be read (receive, as master or slave). This bit is cleared when reading from the ACBSDA register during a receive, or when written to during a transmit. When the ACBCTL1.START bit is set, reading the ACBSDA register does not clear the SDAST bit. This enables the ACB to send a repeated start in master receive mode. 0 – ACB module is not waiting for data transfer. 1 – ACB module is waiting for data to be loaded or unloaded. The Slave Stop bit indicates that a Stop Condition was detected after a slave transfer (i.e., after a slave transfer in which MATCH or GCMATCH is set). Writing 1 to SLVSTP clears it. It is also cleared when the module is disabled. Writing 0 to SLVSTP is ignored. 0 – No stop condition after slave transfer occurred. 1 – Stop condition after slave transfer occurred. ACB Control Status Register (ACBCST) The ACBCST register is a byte-wide, read/write register that maintains current ACB status. At reset and when the module is disabled, the non-reserved bits of ACBCST are cleared. 7 6 5 4 3 2 1 0 Reserved TGSCL TSDA GCMTCH MATCH BB BUSY BUSY 135 The BUSY bit indicates that the ACB module is: Generating a Start Condition In Master mode (ACBST.MASTER is set) In Slave mode (ACBCST.MATCH or ACBCST.GCMTCH is set) In the period between detecting a Start and completing the reception of the address byte. After this, the ACB either becomes not busy or enters slave mode. The BUSY bit is cleared by the completion of any of the above states, and by disabling the module. BUSY is a read only bit. It must always be written with 0. 0 – ACB module is not busy. 1 – ACB module is busy. www.national.com CP3BT10 MASTER CP3BT10 BB MATCH GCMTCH TSDA TGSCL The Bus Busy bit indicates the bus is busy. It is set when the bus is active (i.e., a low level on either SDA or SCL) or by a Start Condition. It is cleared when the module is disabled, on detection of a Stop Condition, or when writing 1 to this bit. See “Usage Hints” on page 138 for a description of the use of this bit. This bit should be set when either the SDA or SCL signals are low. This is done by sampling the SDA and SCL signals continuously and setting the bit if one of them is low. The bit remains set until cleared by a STOP condition or written with 1. 0 – Bus is not busy. 1 – Bus is busy. The Address Match bit indicates in slave mode when ACBADDR.SAEN is set and the first seven bits of the address byte (the first byte transferred after a Start Condition) matches the 7-bit address in the ACBADDR register, or when ACBADDR2.SAEN is set and the first seven bits of the address byte matches the 7-bit address in the ACBADDR2 register. It is cleared by Start Condition or repeated Start and Stop Condition (including illegal Start or Stop Condition). 0 – No address match occurred. 1 – Address match occurred. The Global Call Match bit is set in slave mode when the ACBCTL1.GCMEN bit is set and the address byte (the first byte transferred after a Start Condition) is 00h. It is cleared by a Start Condition or repeated Start and Stop Condition (including illegal Start or Stop Condition). 0 – No global call match occurred. 1 – Global call match occurred. The Test SDA bit samples the state of the SDA signal. This bit can be used while recovering from an error condition in which the SDA signal is constantly pulled low by a slave that went out of sync. This bit is a read-only bit. Data written to it is ignored. The Toggle SCL bit enables toggling the SCL signal during error recovery. When the SDA signal is low, writing 1 to this bit drives the SCL signal high for one cycle. Writing 1 to TGSCL when the SDA signal is high is ignored. The bit is cleared when the clock toggle is completed. 0 – Writing 0 has no effect. 1 – Writing 1 toggles the SDA signal high for one cycle. www.national.com 21.3.4 ACB Control Register 1 (ACBCTL1) The ACBCTL1 register is a byte-wide, read/write register that configures and controls the ACB module. At reset and while the module is disabled (ACBCTL2.ENABLE = 0), the ACBCTL1 register is cleared. 7 6 5 4 3 2 1 0 STASTRE NMINTE GCMEN ACK Res. INTEN STOP START START STOP 136 The Start bit is set to generate a Start Condition on the ACCESS.bus. The START bit is cleared when the Start Condition is sent, or upon detection of a Bus Error (ACBST.BER = 1). This bit should be set only when in Master mode, or when requesting Master mode. If this device is not the active master of the bus (ACBST.MASTER = 0), setting the START bit generates a Start Condition as soon as the ACCESS.bus is free (ACBCST.BB = 0). An address send sequence should then be performed. If this device is the active master of the bus (ACBST.MASTER = 1), when the START bit is set, a write to the ACBSDA register generates a Start Condition, then the ACBSDA data is transmitted as the slave’s address and the requested transfer direction. This case is a repeated Start Condition. It may be used to switch the direction of the data flow between the master and the slave, or to choose another slave device without using a Stop Condition in between. 0 – Writing 0 has no effect. 1 – Writing 1 generates a Start condition. The Stop bit in master mode generates a Stop Condition that completes or aborts the current message transfer. This bit clears itself after the the Stop condition is issued. 0 – Writing 0 has no effect. 1 – Writing 1 generates a Stop condition. ACK GCMEN NMINTE STASTRE The Interrupt Enable bit controls generating ACB interrupts. When the INTEN bit is cleared ACB interrupt is disabled. When the INTEN bit is set, interrupts are enabled. 0 – ACB interrupts disabled. 1 – ACB interrupts enabled. An interrupt is generated (the interrupt signal to the ICU is high) on any of the following events: An address MATCH is detected (ACBST.NMATCH = 1) and the NMINTE bit is set. A Bus Error occurs (ACBST.BERR = 1). Negative acknowledge after sending a byte (ACBST.NEGACK = 1). An interrupt is generated on acknowledge of each transaction (same as hardware setting the ACBST.SDAST bit). If ACBCTL1.STASTRE = 1, in master mode after a successful start (ACBST.STASTR = 1). Detection of a Stop Condition while in slave receive mode (ACBST.SLVSTP = 1). The Acknowledge bit holds the value this device sends in master or slave mode during the next acknowledge cycle. Setting this bit to 1 instructs the transmitting device to stop sending data, since the receiver either does not need, or cannot receive, any more data. This bit is cleared after the first acknowledge cycle. This bit is ignored when in transmit mode. The Global Call Match Enable bit enables the match of an incoming address byte to the general call address (Start Condition followed by address byte of 00h) while the ACB is in slave mode. When cleared, the ACB does not respond to a global call. 0 – Global call matching disabled. 1 – Global call matching enabled. The New Match Interrupt Enable controls whether ACB interrupts are generated on new matches. Set the NMINTE bit to enable the interrupt on a new match (i.e., when ACBST.NMATCH is set). The interrupt is issued only if the ACBCTL1.INTEN bit is set. 0 – New match interrupts disabled. 1 – New match interrupts enabled. The Stall After Start Enable bit enables the stall after start mechanism. When enabled, the ACB is stalled after the address byte. When the STASTRE bit is clear, the ACBST.STASTR bit is always clear. 0 – No stall after start. 1 – Stall-after-start enabled. 21.3.5 ACB Control Register 2 (ACBCTL2) The ACBCTL2 register is a byte-wide, read/write register that controls the module and selects the ACB clock rate. At reset, the ACBCTL2 register is cleared. 7 1 0 SCLFRQ6:0 ENABLE The Enable bit controls the ACB module. When this bit is set, the ACB module is enabled. When the Enable bit is clear, the ACB module is disabled, the ACBCTL1, ACBST, and ACBCST registers are cleared, and the clocks are halted. 0 – ACB module disabled. 1 – ACB module enabled. The SCL Frequency field specifies the SCL period (low time and high time) in master mode. The clock low time and high time are defined as follows: tSCLl = tSCLh = 2 × SCLFRQ × tCLK Where tCLK is this device’s clock period when in Active mode. The SCLFRQ field may be programmed to values in the range of 0001000b through 1111111b. Using any other value has unpredictable results. SCLFRQ 21.3.6 ENABLE ACB Control Register 3 (ACBCTL3) The ACBCTL3 register is a byte-wide, read/write register that expands the clock prescaler field and enables ARP matches. At reset, the ACBCTL3 register is cleared. 7 3 Reserved ARPMEN SCLFRQ 137 2 ARPMEN 1 0 SCLFRQ8:7 The ARP Match Enable bit enables the matching of an incoming address byte to the SMBus ARP address 110 0001b general call address (Start condition followed by address byte of 00h), while the ACB is in slave mode. 0 – ACB does not respond to ARP addresses. 1 – ARP address matching enabled. The SCL Frequency field specifies the SCL period (low time and high time) in master mode. The ACBCTL3 register provides a 2-bit expansion of this field, with the remaining 7 bits being held in the ACBCTL2 register. www.national.com CP3BT10 INTEN CP3BT10 21.3.7 21.4 ACB Own Address Register 1 (ACBADDR1) The ACBADDR1 register is a byte-wide, read/write register that holds the module’s first ACCESS.bus address. After reset, its value is undefined. 7 6 0 SAEN ADDR ADDR The Own Address field holds the first 7-bit ACCESS.bus address of this device. When in slave mode, the first 7 bits received after a Start Condition are compared to this field (first bit received to bit 6, and the last to bit 0). If the address field matches the received data and the SAEN bit is set, a match is detected. The Slave Address Enable bit controls whether address matching is performed in slave mode. When set, the SAEN bit indicates that the ADDR field holds a valid address and enables the match of ADDR to an incoming address byte. When cleared, the ACB does not check for an address match. 0 – Address matching disabled. 1 – Address matching enabled. SAEN 21.3.8 ACB Own Address Register 2 (ACBADDR2) The ACBADDR2 register is a byte-wide, read/write register that holds the module’s second ACCESS.bus address. After reset, its value is undefined. 7 6 0 SAEN ADDR SAEN ADDR The Own Address field holds the second 7-bit ACCESS.bus address of this device. When in slave mode, the first 7 bits received after a Start Condition are compared to this field (first bit received to bit 6, and the last to bit 0). If the address field matches the received data and the SAEN bit is set, a match is detected. The Slave Address Enable bit controls whether address matching is performed in slave mode. When set, the SAEN bit indicates that the ADDR field holds a valid address and enables the match of ADDR to an incoming address byte. When cleared, the ACB does not check for an address match. 0 – Address matching disabled. 1 – Address matching enabled. www.national.com USAGE HINTS When the ACB module is disabled, the ACBCST.BB bit is cleared. After enabling the ACB (ACBCTL2.ENABLE = 1) in systems with more than one master, the bus may be in the middle of a transaction with another device, which is not reflected in the BB bit. There is a need to allow the ACB to synchronize to the bus activity status before issuing a request to become the bus master, to prevent bus errors. Therefore, before issuing a request to become the bus master for the first time, software should check that there is no activity on the bus by checking the BB bit after the bus allowed time-out period. When waking up from power down, before checking the ACBCST.MATCH bit, test the ACBCST.BUSY bit to make sure that the address transaction has finished. The BB bit is intended to solve a deadlock in which two, or more, devices detect a usage conflict on the bus and both devices cease being bus masters at the same time. In this situation, the BB bits of both devices are active (because each deduces that there is another master currently performing a transaction, while in fact no device is executing a transaction), and the bus would stay locked until some device sends a ACBCTL1.STOP condition. The ACBCST.BB bit allows software to monitor bus usage, so it can avoid sending a STOP signal in the middle of the transaction of some other device on the bus. This bit detects whether the bus remains unused over a certain period, while the BB bit is set. In some cases, the bus may get stuck with the SCL or SDA lines active. A possible cause is an erroneous Start or Stop Condition that occurs in the middle of a slave receive session. When the SCL signal is stuck active, there is nothing that can be done, and it is the responsibility of the module that holds the bus to release it. When the SDA signal is stuck active, the ACB module enables the release of the bus by using the following sequence. Note that in normal cases, the SCL signal may be toggled only by the bus master. This protocol is a recovery scheme which is an exception that should be used only in the case when there is no other master on the bus. The recovery scheme is as follows: 1. Disable and re-enable the module to set it into the not addressed slave mode. 2. Set the ACBCTL1.START bit to make an attempt to issue a Start Condition. 3. Check if the SDA signal is active (low) by reading ACBCST.TSDA bit. If it is active, issue a single SCL cycle by writing 1 to ACBCST.TGSCL bit. If the SDA line is not active, continue from step 5. 4. Check if the ACBST.MASTER bit is set, which indicates that the Start Condition was sent. If not, repeat step 3 and 4 until the SDA signal is released. 5. Clear the BB bit. This enables the START bit to be executed. Continue according to “Bus Idle Error Recovery” on page 133. 138 The Timing and Watchdog Module (TWM) generates the clocks and interrupts used for timing periodic functions in the system; it also provides Watchdog protection over software execution. Slow Clock period. The prescaled clock signal is called T0IN. The TWM is designed to provide flexibility in system design by configuring various clock ratios and by selecting the Watchdog clock source. After setting the TWM configuration, software can lock it for a higher level of protection against erroneous software action. Once the TWM is locked, only reset can release it. Timer T0 is a programmable 16-bit down counter that can be used as the time base for real-time operations such as a periodic audible tick. It can also be used to drive the Watchdog circuit. 22.1 TWM STRUCTURE Figure 60 is a block diagram showing the internal structure of the Timing and Watchdog module. There are two main sections: the Real-Time Timer (T0) section at the top and the Watchdog section on the bottom. All counting activities of the module are based on the Slow Clock (SLCLK). A prescaler counter divides this clock to make a slower clock. The prescaler factor is defined by a 3bit field in the Timer and Watchdog Prescaler register, which selects either 1, 2, 4, 8, 16, or 32 as the divisor. Therefore, the prescaled clock period can be 2, 4, 8, 16, or 32 times the 22.2 TIMER T0 OPERATION The timer starts counting from the value loaded into the TWMT0 register and counts down on each rising edge of T0IN. When the timer reaches zero, it is automatically reloaded from the TWMT0 register and continues counting down from that value. Therefore, the frequency of the timer is: fSLCLK / [(TWMT0 + 1) × prescaler] When an external crystal oscillator is used as the SLCLK source or when the fast clock is divided accordingly, fSLCLK is 32.768 kHz. The value stored in TWMT0 can range from 0001h to FFFFh. REAL TIME TIMER (T0) Slow Clock 5-Bit Prescaler Counter (TWCP) TWW/MT0 Register T0IN T0CSR Contrl. Reg. T0LINT (to ICU) Restart 16-Bit Timer (Timer0) Underflow WATCHDOG Timer Underflow T0OUT (to Multi-InputWake-Up) Restart WDSDM WATCHDOG Service Logic WDCNT Watchdog Error WDERR WATCHDOG DS080 Figure 60. Timing and Watchdog Module Block Diagram When the counter reaches zero, an internal timer signal called T0OUT is set for one T0IN clock cycle. This signal sets the TC bit in the TWMT0 Control and Status Register (T0CSR). It also generates an interrupt (IRQ14), when enabled by the T0CSR.T0INTE bit. T0OUT is also an input to the MIWU (see Section 13.0), so an edge-triggered interrupt is also available through this alternative mechanism. If software loads the TWMT0 register with a new value, the timer uses that value the next time that it reloads the 16-bit timer register (in other words, after reaching zero). Software can restart the timer at any time (on the very next edge of the T0IN clock) by setting the Restart (RST) bit in the T0CSR register. The T0CSR.RST bit is cleared automatically upon restart of the 16-bit timer. Note: If software wishes to switch to Power Save or Idle mode after setting the T0CSR.RST bit, software must wait for the reset operation to complete before performing the switch. 139 www.national.com CP3BT10 22.0 Timing and Watchdog Module CP3BT10 22.3 WATCHDOG OPERATION 22.3.2 The Watchdog is an 8-bit down counter that operates on the rising edge of a specified clock source. At reset, the Watchdog is disabled; it does not count and no Watchdog signal is generated. A write to either the Watchdog Count (WDCNT) register or the Watchdog Service Data Match (WDSDM) register starts the counter. The Watchdog counter counts down from the value programmed in the WDCNT register. Once started, only a reset can stop the Watchdog from operating. The Watchdog can be programmed to use either T0OUT or T0IN as its clock source (the output and input of Timer T0, respectively). The TWCFG.WDCT0I bit controls this clock selection. Software must periodically “service” the Watchdog. There are two ways to service the Watchdog, the choice depending on the programmed value of the WDSDME bit in the Timer and Watchdog Configuration (TWCFG) register. If the TWCFG.WDSDME bit is clear, the Watchdog is serviced by writing a value to the WDCNT register. The value written to the register is reloaded into the Watchdog counter. The counter then continues counting down from that value. Power Save Mode Operation The Timer and Watchdog Module is active in both the Power Save and Idle modes. The clocks and counters continue to operate normally in these modes. The WDSDM register is accessible in the Power Save and Idle modes, but the other TWM registers are accessible only in the Active mode. Therefore, Watchdog servicing must be carried out using the WDSDM register in the Power Save or Idle mode. In the Halt mode, the entire device is frozen, including the Timer and Watchdog Module. On return to Active mode, operation of the module resumes at the point at which it was stopped. Note: After a restart or Watchdog service through WDCNT, do not enter Power Save mode for a period equivalent to 5 Slow Clock cycles. 22.4 TWM REGISTERS The TWM registers controls the operation of the Timing and Watchdog Module. There are six such registers: If the TWCFG.WDSDME bit is set, the Watchdog is serviced by writing the value 5Ch to the Watchdog Service Data Match (WDSDM) register. This reloads the Watchdog counter with the value previously programmed into the WDCNT register. The counter then continues counting down from that value. A Watchdog error signal is generated by any of the following events: The Watchdog serviced too late. The Watchdog serviced too often. The WDSDM register is written with a value other than 5Ch when WDSDM type servicing is enabled (TWCFG.WDSDME = 1). Table 50 TWM Registers Name Address Description TWCFG FF FF20h Timer and Watchdog Configuration Register TWCP FF FF22h Timer and Watchdog Clock Prescaler Register TWMT0 FF FF24h TWM Timer 0 Register T0CSR FF FF26h TWMT0 Control and Status Register WDCNT FF FF28h Watchdog Count Register WDSDM FF FF2Ah Watchdog Service Data Match Register A Watchdog error condition resets the device. 22.3.1 Register Locking The Timer and Watchdog Configuration (TWCFG) register is used to set the Watchdog configuration. It controls the The WDSDM register is accessible in both Active and PowWatchdog clock source (T0IN or T0OUT), the type of er Save mode. The other TWM registers are accessible only Watchdog servicing (using WDCNT or WDSDM), and the in Active mode. locking state of the TWCFG, TWCPR, TIMER0, T0CSR, and WDCNT registers. A register that is locked cannot be read or written. A write operation is ignored and a read operation returns unpredictable results. If the TWCFG register is itself locked, it remains locked until the device is reset. Any other locked registers also remain locked until the device is reset. This feature prevents a runaway program from tampering with the programmed Watchdog function. www.national.com 140 Timer and Watchdog Configuration Register (TWCFG) 22.4.2 The TWCFG register is a byte-wide, read/write register that selects the Watchdog clock input and service method, and also allows the Watchdog registers to be selectively locked. A locked register cannot be read or written; a read operation returns unpredictable values and a write operation is ignored. Once a lock bit is set, that bit cannot be cleared until the device is reset. At reset, the non-reserved bits of the register are cleared. The register format is shown below. Timer and Watchdog Clock Prescaler Register (TWCP) The TWCP register is a byte-wide, read/write register that specifies the prescaler value used for dividing the low-frequency clock to generate the T0IN clock. At reset, the nonreserved bits of the register are cleared. The register format is shown below. 7 3 2 0 Reserved 7 6 5 4 3 2 1 0 Res. WDSDME WDCT0I LWDCNT LTWMT0 LTWCP LTWCFG LTWCFG LTWCP LTWMT0 LWDCNT WDCT0I WDSDME MDIV The Lock TWCFG Register bit controls access to the TWCFG register. When clear, access to the TWCFG register is allowed. When set, the TWCFG register is locked. 0 – TWCFG register unlocked. 1 – TWCFG register locked. The Lock TWCP Register bit controls access to the TWCP register. When clear, access to the TWCP register is allowed. When set, the TWCP register is locked. 0 – TWCP register unlocked. 1 – TWCP register locked. The Lock TWMT0 Register bit controls access to the TWMT0 register. When clear, access to the TWMT0 and T0CSR registers are allowed. When set, the TWMT0 and T0CSR registers are locked. 0 – TWMT0 register unlocked. 1 – TWMT0 register locked. The Lock LDWCNT Register bit controls access to the LDWCNT register. When clear, access to the LDWCNT register is allowed. When set, the LDWCNT register is locked. 0 – LDWCNT register unlocked. 1 – LDWCNT register locked. The Watchdog Clock from T0IN bit selects the clock source for the Watchdog timer. When clear, the T0OUT signal (the output of Timer T0) is used as the Watchdog clock. When set, the T0IN signal (the prescaled Slow Clock) is used as the Watchdog clock. 0 – Watchdog timer is clocked by T0OUT. 1 – Watchdog timer is clocked by T0IN. The Watchdog Service Data Match Enable bit controls which method is used to service the Watchdog timer. When clear, Watchdog servicing is accomplished by writing a count value to the WDCNT register; write operations to the Watchdog Service Data Match (WDSDM) register are ignored. When set, Watchdog servicing is accomplished by writing the value 5Ch to the WDSDM register. 0 – Write a count value to the WDCNT register to service the Watchdog timer. 1 – Write 5Ch to the WDSDM register to service the Watchdog timer. MDIV 22.4.3 Main Clock Divide. This 3-bit field defines the prescaler factor used for dividing the low speed device clock to create the T0IN clock. The allowed 3-bit values and the corresponding clock divisors and clock rates are listed below. MDIV Clock Divisor (fSCLK = 32.768 kHz) T0IN Frequency 000 1 32.768 kHz 001 2 16.384 kHz 010 4 8.192 kHz 011 8 4.096 kHz 100 16 2.056 kHz 101 32 1.024 kHz Other Reserved N/A TWM Timer 0 Register (TWMT0) The TWMT0 register is a word-wide, read/write register that defines the T0OUT interrupt rate. At reset, TWMT0 register is initialized to FFFFh. The register format is shown below. 15 0 PRESET PRESET 141 The Timer T0 Preset field holds the value used to reload Timer T0 on each underflow. Therefore, the frequency of the Timer T0 interrupt is the frequency of T0IN divided by (PRESET+1). The allowed values of PRESET are 0001h through FFFFh. www.national.com CP3BT10 22.4.1 CP3BT10 22.4.4 TWMT0 Control and Status Register (T0CSR) 22.4.5 The T0CSR register is a byte-wide, read/write register that controls Timer T0 and shows its current status. At reset, the non-reserved bits of the register are cleared. The register format is shown below. 7 5 Reserved 4 3 FRZT0E WDLTD 2 1 0 T0INTE TC RST Watchdog Count Register (WDCNT) The WDCNT register is a byte-wide, write-only register that holds the value that is loaded into the Watchdog counter each time the Watchdog is serviced. The Watchdog is started by the first write to this register. Each successive write to this register restarts the Watchdog count with the written value. At reset, this register is initialized to 0Fh. 7 0 PRESET RST TC T0INTE WDLTD FRZT0E The Restart bit is used to reset Timer T0. When this bit is set, it forces the timer to reload the value in the TWMT0 register on the next rising edge of the selected input clock. The RST bit is reset automatically by the hardware on the same rising edge of the selected input clock. Writing a 0 to this bit position has no effect. At reset, the non-reserved bits of the register are cleared. 0 – Writing 0 has no effect. 1 – Writing 1 resets Timer T0. The Terminal Count bit is set by hardware when the Timer T0 count reaches zero and is cleared when software reads the T0CSR register. It is a read-only bit. Any data written to this bit position is ignored. The TC bit is not cleared if FREEZE mode is asserted by an external debugging system. 0 – Timer T0 did not count down to 0. 1 – Timer T0 counted down to 0. The Timer T0 Interrupt Enable bit enables an interrupt to the CPU each time the Timer T0 count reaches zero. When this bit is clear, Timer T0 interrupts are disabled. 0 – Timer T0 interrupts disabled. 1 – Timer T0 interrupts enabled. The Watchdog Last Touch Delay bit is set when either WDCNT or WDSDM is written and the data transfer to the Watchdog is in progress (see WDCNT and WDSDM register description). When clear, it is safe to switch to Power Save mode. 0 – No data transfer to the Watchdog is in progress, safe to enter Power Save mode. 1 – Data transfer to the Watchdog in progress. The Freeze Timer0 Enable bit controls whether TImer 0 is stopped in FREEZE mode. If this bit is set, the Timer 0 is frozen (stopped) when the FREEZE input to the TWM is asserted. If the FRZT0E bit is clear, only the Watchdog timer is frozen by asserting the FREEZE input signal. After reset, this bit is clear. 0 – Timer T0 unaffected by FREEZE mode. 1 – Timer T0 stopped in FREEZE mode. www.national.com 22.4.6 Watchdog Service Data Match Register (WDSDM) The WSDSM register is a byte-wide, write-only register used for servicing the Watchdog. When this type of servicing is enabled (TWCFG.WDSDME = 1), the Watchdog is serviced by writing the value 5Ch to the WSDSM register. Each such servicing reloads the Watchdog counter with the value previously written to the WDCNT register. Writing any data other than 5Ch triggers a Watchdog error. Writing to the register more than once in one Watchdog clock cycle also triggers a Watchdog error signal. If this type of servicing is disabled (TWCFG.WDSDME = 0), any write to the WSDSM register is ignored. 7 0 RSTDATA 22.5 WATCHDOG PROGRAMMING PROCEDURE The highest level of protection against software errors is achieved by programming and then locking the Watchdog registers and using the WDSDM register for servicing. This is the procedure: 142 1. Write the desired values into the TWM Clock Prescaler register (TWCP) and the TWM Timer 0 register (TWMT0) to control the T0IN and T0OUT clock rates. The frequency of T0IN can be programmed to any of six frequencies ranging from 1/32 × fSLCLK to fSLCLK. The frequency of T0OUT is equal to the frequency of T0IN divided by (1+ PRESET), in which PRESET is the value written to the TWMT0 register. 2. Configure the Watchdog clock to use either T0IN or T0OUT by setting or clearing the TWCFG.WDCT0I bit. 3. Write the initial value into the WDCNT register. This starts operation of the Watchdog and specifies the maximum allowed number of Watchdog clock cycles between service operations. 4. Set the T0CSR.RST bit to restart the TWMT0 timer. 5. Lock the Watchdog registers and enable the Watchdog Service Data Match Enable function by setting bits 0, 1, 2, 3, and 5 in the TWCFG register. 6. Service the Watchdog by periodically writing the value 5Ch to the WDSDM register at an appropriate rate. Servicing must occur at least once per period programmed into the WDCNT register, but no more than once in a single Watchdog input clock cycle. Processor-Independent Pulse Width Modulation (PWM) mode, which generates pulses of a specified width and duty cycle, and which also provides a general-purpose timer/counter. Input Capture mode, which measures the elapsed time between occurrences of external events, and which also provides a general-purpose timer/counter. The timer unit uses an I/O pin called TA, which is an alternate function of the PI7 port pin. 23.1 TIMER STRUCTURE Figure 61 is a block diagram showing the internal structure of the MFT. There are two main functional blocks: a Timer/ Counter and Action block and a Clock Source block. The Timer/Counter and Action block contains two separate timer/counter units, called Timer/Counter 1 and Timer/Counter 2. Timer/Counter Clock Source Action Reload/Capture A TCRA Clock Prescaler/Selector System Clock Dual Independent Timer mode, which generates system timing signals. Timer/Counter 1 TCNT1 Reload/Capture B TCRB Timer/Counter 2 TCNT2 External Event Toggle/Capture/Interrupt The Multi-Function Timer module contains a pair of 16-bit timer/counters. Each timer/counter unit offers a choice of clock sources for operation and can be configured to operate in any of the following modes: TA Interrupt A Interrupt B PWM/Capture/Counter Mode Select + Control DS165 Figure 61. Multi-Function Timer Block Diagram 23.1.1 Timer/Counter Block The Timer/Counter block contains the following functional blocks: Two 16-bit counters, Timer/Counter 1 (TCNT1) and Timer/Counter 2 (TCNT2) Two 16-bit reload/capture registers, TCRA and TCRB Control logic necessary to configure the timer to operate in any of the four operating modes Interrupt control and I/O control logic In a power-saving mode that uses the low-frequency (32.768 kHz) clock as the System Clock, the synchronization circuit requires that the Slow Clock operate at no more than one-fourth the speed of the 32.768 kHz System Clock. 23.1.2 Clock Source Block The Clock Source block generates the signals used to clock the two timer/counter registers. The internal structure of the Clock Source block is shown in Figure 62. No Clock Counter 1 Clock Select Counter 1 Clock Counter 2 Clock Select Counter 2 Clock Prescaler Register TPRSC Reset System Clock 5-Bit Prescaler Counter Prescaled Clock DS164 Figure 62. Multi-Function Timer Clock Source 143 www.national.com CP3BT10 23.0 Multi-Function Timer CP3BT10 23.2 Counter Clock Source Select TIMER OPERATING MODES There are two clock source selectors that allow software to Each timer/counter unit can be configured to operate in any independently select the clock source for each of the two of the following modes: 16-bit counters from any one of the following sources: Processor-Independent Pulse Width Modulation (PWM) No clock (which stops the counter) mode Prescaled System Clock Input Capture mode Slow Clock (derived from the low-frequency oscillator or Dual Independent Timer mode divided from the high-speed oscillator) At reset, the timers are disabled. To configure and start the timers, software must write a set of values to the registers Prescaler that control the timers. The registers are described in The 5-bit clock prescaler allows software to run the timer Section 23.5. with a prescaled clock signal. The prescaler consists of a 5bit read/write prescaler register (TPRSC) and a 5-bit down counter. The System Clock is divided by the value contained in the prescaler register plus 1. Therefore, the timer clock period can be set to any value from 1 to 32 divisions of the System Clock period. The prescaler register and down counter are both cleared upon reset. Slow Clock The Slow Clock is generated by the Triple Clock and Reset module. The clock source is either the divided fast clock or the external 32.768 kHz crystal oscillator (if available and selected). The Slow Clock can be used as the clock source for the two 16-bit counters. Because the Slow Clock can be asynchronous to the System Clock, a circuit is provided to synchronize the clock signal to the high-frequency System Clock before it is used for clocking the counters. The synchronization circuit requires that the Slow Clock operate at no more than one-fourth the speed of the System Clock. Limitations in Low-Power Modes The Power Save mode uses the Slow Clock as the System Clock. In this mode, the Slow Clock cannot be used as a clock source for the timers because that would drive both clocks at the same frequency, and the clock ratio needed for synchronization to the System Clock would not be maintained. However, the External Event Clock and Pulse Accumulate Mode will still work, as long as the external event pulses are at least the size of the whole slow-clock period. Using the prescaled System Clock will also work, but at a much slower rate than the original System Clock. Idle and Halt modes stop the System Clock (the high-frequency and/or low-frequency clock) completely. If the System Clock is stopped, the timer stops counting until the System Clock resumes operation. In the Idle or Halt mode, the System Clock stops completely, which stops the operation of the timers. In that case, the timers stop counting until the System Clock resumes operation. www.national.com 144 Mode 1: Processor-Independent PWM functions as the time base for the PWM timer. It counts Mode 1 is the Processor-Independent Pulse Width Modula- down at the clock rate selected for the counter. When an untion (PWM) mode, which generates pulses of a specified derflow occurs, the timer register is reloaded alternately width and duty cycle, and which also provides a separate from the TCRA and TCRB registers, and counting proceeds downward from the loaded value. general-purpose timer/counter. Figure 63 is a block diagram of the Multi-Function Timer configured to operate in Mode 1. Timer/Counter 1 (TCNT1) Reload A = Time 1 TCRA TAPND Timer Interrupt A Underflow TAIEN Timer 1 Clock Timer/Counter 1 TCNT1 TA TAEN Underflow Timer Interrupt B TBIEN Reload B = Time 2 TCRB Timer 2 Clock TBPND Timer/Counter 2 TCNT2 Timer Interrupt D TDIEN TDPND Figure 63. DS166 Processor-Independent PWM Mode On the first underflow, the timer is loaded from the TCRA register, then from the TCRB register on the next underflow, then from the TCRA register again on the next underflow, and so on. Every time the counter is stopped and restarted, it always obtains its first reload value from the TCRA register. This is true whether the timer is restarted upon reset, after entering Mode 1 from another mode, or after stopping and restarting the clock with the Timer/Counter 1 clock selector. The timer can be configured to toggle the TA output bit on each underflow. This generates a clock signal on the TA output with the width and duty cycle determined by the values stored in the TCRA and TCRB registers. This is a “processor-independent” PWM clock because once the timer is set up, no more action is required from the CPU to generate a continuous PWM signal. The timer can be configured to generate separate interrupts upon reload from the TCRA and TCRB registers. The interrupts can be enabled or disabled under software control. The CPU can determine the cause of each interrupt by looking at the TAPND and TBPND bits, which are updated by the hardware on each occurrence of a timer reload. In Mode 1, Timer/Counter 2 (TCNT2) can be used either as a simple system timer, an external event counter, or a pulseaccumulate counter. The clock counts down using the clock selected with the Timer/Counter 2 clock selector. It generates an interrupt upon each underflow if the interrupt is enabled with the TDIEN bit. 145 www.national.com CP3BT10 23.2.1 CP3BT10 23.2.2 Mode 2: Input Capture Mode 2 is the Input Capture mode, which measures the elapsed time between occurrences of external events, and which also provides a separate general-purpose timer/ counter. Figure 64 is a block diagram of the Multi-Function Timer configured to operate in Mode 2. The time base of the cap- ture timer depends on Timer/Counter 1, which counts down using the clock selected with the Timer/Counter 1 clock selector. The TA pin functions as a capture input. A transition received on the TA pin transfers the timer contents to the TCRA register. The TA pin can be configured to sense either rising or falling edges. Timer Interrupt 1 TAIEN TAPND Capture A TCRA TA Preset TAEN Timer 1 Clock Timer/Counter 1 TCNT1 TCPND Underflow Timer Interrupt 1 TCIEN TDPND Timer 2 Clock Timer/Counter 2 TnCNT2 Underflow Timer Interrupt 2 TDIEN DS167 Figure 64. Input Capture Mode The TA input can be configured to preset the counter to FFFFh on reception of a valid capture event. In this case, the current value of the counter is transferred to the corresponding capture register and then the counter is preset to FFFFh. Using this approach allows software to determine the on-time and off-time and period of an external signal with a minimum of CPU overhead. In Mode 2, Timer/Counter 2 (TCNT2) can be used as a simple system timer. The clock counts down using the clock selected with the Timer/Counter 2 clock selector. It generates an interrupt upon each underflow if the interrupt is enabled with the TDIEN bit. The values captured in the TCRA register at different times reflect the elapsed time between transitions on the TA pin. The input signal on the TA pin must have a pulse width equal to or greater than one System Clock cycle. There are two separate interrupts associated with the capture timer, each with its own enable bit and pending bit. The interrupt events are reception of a transition on the TA pin and underflow of the TCNT1 counter. The enable bits for these events are TAIEN and TCIEN, respectively. www.national.com 146 Mode 3: Dual Independent Timer/Counter Mode 3 is the Dual Independent Timer mode, which generates system timing signals or counts occurrences of external events. Figure 65 is a block diagram of the Multi-Function Timer configured to operate in Mode 3. The timer is configured to operate as a dual independent system timer or dual external event counter. In addition, Timer/Counter 1 can generate a 50% duty cycle PWM signal on the TA pin. Reload A TCRA TAPND Timer Interrupt 1 Underflow TAIEN Timer 1 Clock Timer/Counter 1 TCNT1 TA TAEN Reload B TCRB Timer Interrupt 2 Underflow TDIEN Timer 2 Clock Timer/Counter 2 TCNT2 TDPND DS168 Figure 65. Dual-Independent Timer/Counter Mode Timer/Counter 1 (TCNT1) counts down at the rate of the selected clock. On underflow, it is reloaded from the TCRA register and counting proceeds down from the reloaded value. In addition, the TA pin is toggled on each underflow if this function is enabled by the TAEN bit. The initial state of the TA pin is software-programmable. When the TA pin is toggled from low to high, it sets the TCPND interrupt pending bit and also generates an interrupt if enabled by the TAIEN bit. Timer/Counter 2 (TCNT2) counts down at the rate of the selected clock. On underflow, it is reloaded from the TCRB register and counting proceeds down from the reloaded value. In addition, each underflow sets the TDPND interrupt pending bit and generates an interrupt if the interrupt is enabled by the TDIEN bit. Because the TA pin toggles on every underflow, a 50% duty cycle PWM signal can be generated on the TA pin without any further action from the CPU. 147 www.national.com CP3BT10 23.2.3 CP3BT10 23.3 TIMER INTERRUPTS 23.4 Each Multi-Function Timer unit has four interrupt sources, designated A, B, C, and D. Interrupt sources A, B, and C are mapped into a single system interrupt called Timer Interrupt 1, while interrupt source D is mapped into a system interrupt called Timer Interrupt 2. Each of the four interrupt sources has its own enable bit and pending bit. The enable bits are named TAIEN, TBIEN, TCIEN, and TDIEN. The pending bits are named TAPND, TBPND, TCPND, and TDPND. Timer Interrupts 1 and 2 are system interrupts TA and TB (IRQ14 and IRQ13), respectively. TIMER I/O FUNCTIONS Table 52 shows the functions of the TA pin in each operating mode, and for each combination of enable bit settings. When the TA pin is configured to operate as a PWM output (TAEN = 1), the state of the pin is toggled on each underflow of the TCNT1 counter. In this case, the initial value on the pin is determined by the TAOUT bit. For example, to start with TA high, software must set the TAOUT bit before enabling the timer clock. This option is available only when the timer is configured to operate in Mode 1 or 3 (in other words, when TCRA is not used in Capture mode). Table 51 shows the events that trigger interrupts A, B, C, and D in each of the four operating modes. Note that some interrupt sources are not used in some operating modes. Table 51 Timer Interrupts Overview Interrupt Pending Bit Sys. Int. Timer Int. 1 (TA Int.) Timer Int. 2 (TB Int.) Mode 1 Mode 2 Mode 3 PWM + Counter Dual Input Capture + Counter Dual Counter TAPND TCNT1 reload from TCRA Input capture on TA transition TCNT1 reload from TCRA TBPND TCNT1 reload from TCRB Input Capture on TB transition N/A TCPND N/A TCNT1 underflow N/A TDPND TCNT2 underflow TCNT2 underflow TCNT2 reload from TCRB Table 52 Timer I/O Functions TAEN TBEN I/O TA Mode 1 Mode 2 Mode 3 PWM + Counter Dual Input Capture + counter Dual Counter TAEN = 0 TBEN = X No Output Capture TCNT1 into TCRA No Output Toggle TAEN = 1 TBEN = X Toggle Output on Underflow of TCNT1 Capture TCNT1 into TCRA and Preset TCNT1 Toggle Output on Underflow of TCNT1 www.national.com 148 TIMER REGISTERS 23.5.2 Table 53 lists the CPU-accessible registers used to control the Multi-Function Timers. Table 53 Multi-Function Timer Registers Name Address Description TPRSC FF FF48h Clock Prescaler Register TCKC FF FF4Ah Clock Unit Control Register TCNT1 FF FF40h Timer/Counter 1 Register TCNT2 FF FF46h Timer/Counter 2 Register TCRA FF FF42h Reload/Capture A Register TCRB FF FF44h Reload/Capture B Register TCTRL FF FF4Ch Timer Mode Control Register TICTL FF FF4Eh Timer Interrupt Control Register TICLR FF FF50h Timer Interrupt Clear Register The TCKC register is a byte-wide, read/write register that selects the clock source for each timer/counter. Selecting the clock source also starts the counter. This register is cleared on reset, which disables the timer/counters. The register format is shown below. 7 C2CSEL Clock Prescaler Register (TPRSC) The TPRSC register is a byte-wide, read/write register that holds the current value of the 5-bit clock prescaler (CLKPS). This register is cleared on reset. The register format is shown below. 7 5 Reserved CLKPS 4 6 Reserved C1CSEL 23.5.1 Clock Unit Control Register (TCKC) 5 3 C2CSEL 2 0 C1CSEL The Counter 1 Clock Select field specifies the clock mode for Timer/Counter 1 as follows: 000 – No clock (Timer/Counter 1 stopped, modes 1, 2, and 3 only). 001 – Prescaled System Clock. 010 – Reserved. 011 – Reserved. 100 – Slow Clock.* 101 – Reserved. 110 – Reserved. 111 – Reserved. The Counter 2 Clock Select field specifies the clock mode for Timer/Counter 2 as follows: 000 – No clock (Timer/Counter 2 stopped, modes 1, 2, and 3 only). 001 – Prescaled System Clock. 010 – Reserved. 011 – Reserved. 100 – Slow Clock* 101 – Reserved. 110 – Reserved. 111 – Reserved. * Operation of the Slow Clock is determined by the CRCTRL.SCLK control bit, as described in Section 11.8.1. 23.5.3 Timer/Counter 1 Register (TCNT1) The TCNT1 register is a word-wide, read/write register that holds the current count value for Timer/Counter 1. The register contents are not affected by a reset and are unknown after power-up. 0 CLKPS The Clock Prescaler field specifies the divisor used to generate the Timer Clock from the System Clock. When the timer is configured to use the prescaled clock, the System Clock is divided by (CLKPS + 1) to produce the timer clock. Therefore, the System Clock divisor can range from 1 to 32. 15 0 TCNT1 23.5.4 Timer/Counter 2 Register (TCNT2) The TCNT2 register is a word-wide, read/write register that holds the current count value for Timer/Counter 2. The register contents are not affected by a reset and are unknown after power-up. 15 0 TCNT2 149 www.national.com CP3BT10 23.5 CP3BT10 23.5.5 Reload/Capture A Register (TCRA) TAEN The TA Enable bit controls whether the TA pin is enabled to operate as a preset input or as a PWM output, depending on the timer operating mode. In Mode 2 (Dual Input Capture), a transition on the TA pin presets the TCNT1 counter to FFFFh. In the other modes, TA functions as a PWM output. When this bit is clear, operation of the pin for the timer/counter is disabled. 0 – TA input disabled. 1 – TA input enabled. The TA Output Data bit indicates the current state of the TA pin when the pin is used as a PWM output. The hardware sets and clears this bit, but software can also read or write this bit at any time and therefore control the state of the output pin. In case of conflict, a software write has precedence over a hardware update. This bit setting has no effect when the TA pin is used as an input. 0 – TA pin is low. 1 – TA pin is high. The Timer Enable bit controls whether the Multi-Function Timer is enabled. When the module is disabled all clocks to the counter unit are stopped to minimize power consumption. For that reason, the timer/counter registers (TCNT1 and TCNT2), the capture/reload registers (TCRA and TCRB), and the interrupt pending bits (TXPND) cannot be written in this mode. Also, the 5-bit clock prescaler and the interrupt pending bits are cleared, and the TA I/O pin becomes an input. 0 – Multi-Function Timer is disabled. 1 – Multi-Function Timer is enabled. The TCRA register is a word-wide, read/write register that holds the reload or capture value for Timer/Counter 1. The register contents are not affected by a reset and are unknown after power-up. 15 0 TCRA 23.5.6 TAOUT Reload B Register (TCRB) The TCRB register is a word-wide, read/write register that holds the reload value for Timer/Counter 2. The register contents are not affected by a reset and are unknown after power-up. 15 0 TCRB 23.5.7 TEN Timer Mode Control Register (TCTRL) The TCTRL register is a byte-wide, read/write register that sets the operating mode of the timer/counter and the TA pin. This register is cleared at reset. The register format is shown below. 7 6 5 TEN TAOUT Res. MDSEL TAEDG 4 3 TAEN Res. 2 1 0 TAEDG MDSEL The Mode Select field sets the operating mode of the timer/counter as follows: 00 – Mode 1: PWM plus system timer. 01 – Mode 2: Input Capture plus system timer. 10 – Mode 3: Dual Timer/Counter. 11 – Reserved. The TA Edge Polarity bit selects the polarity of the edges that trigger the TA input. 0 – TA input is sensitive to falling edges (high to low transitions). 1 – TA input is sensitive to rising edges (low to high transitions). 23.5.8 Timer Interrupt Control Register (TICTL) The TICTL register is a byte-wide, read/write register that contains the interrupt enable bits and interrupt pending bits for the four timer interrupt sources, designated A, B, C, and D. The condition that causes each type of interrupt depends on the operating mode, as shown in Table 51. This register is cleared upon reset. The register format is shown below. 7 6 5 4 3 2 1 0 TDIEN TCIEN TBIEN TAIEN TDPND TCPND TBPND TAPND TAPND www.national.com 150 The Timer Interrupt Source A Pending bit indicates that timer interrupt condition A has occurred. For an explanation of interrupt conditions A, B, C, and D, see Table 51. This bit can be set by hardware or by software. To clear this bit, software must use the Timer Interrupt Clear Register (TICLR). Any attempt by software to directly write a 0 to this bit is ignored. 0 – Interrupt source A has not triggered. 1 – Interrupt source A has triggered. TCPND TDPND TAIEN TBIEN TCIEN TDIEN The Timer Interrupt Source B Pending bit indicates that timer interrupt condition B has occurred. For an explanation of interrupt conditions A, B, C, and D, see Table 51. This bit can be set by hardware or by software. To clear this bit, software must use the Timer Interrupt Clear Register (TICLR). Any attempt by software to directly write a 0 to this bit is ignored. 0 – Interrupt source B has not triggered. 1 – Interrupt source B has triggered. The Timer Interrupt Source C Pending bit indicates that timer interrupt condition C has occurred. For an explanation of interrupt conditions A, B, C, and D, see Table 51. This bit can be set by hardware or by software. To clear this bit, software must use the Timer Interrupt Clear Register (TICLR). Any attempt by software to directly write a 0 to this bit is ignored. 0 – Interrupt source C has not triggered. 1 – Interrupt source C has triggered. The Timer Interrupt Source D Pending bit indicates that timer interrupt condition D has occurred. For an explanation of interrupt conditions A, B, C, and D, see Table 51. This bit can be set by hardware or by software. To clear this bit, software must use the Timer Interrupt Clear Register (TICLR). Any attempt by software to directly write a 0 to this bit is ignored. 0 – Interrupt source D has not triggered. 1 – Interrupt source D has triggered. The Timer Interrupt A Enable bit controls whether an interrupt is generated on each occurrence of interrupt condition A. For an explanation of interrupt conditions A, B, C, and D, see Table 51. 0 – Condition A interrupts disabled. 1 – Condition A interrupts enabled. The Timer Interrupt B Enable bit controls whether an interrupt is generated on each occurrence of interrupt condition B. For an explanation of interrupt conditions A, B, C, and D, see Table 51. 0 – Condition B interrupts disabled. 1 – Condition B interrupts enabled. The Timer Interrupt C Enable bit controls whether an interrupt is generated on each occurrence of interrupt condition C. For an explanation of interrupt conditions A, B, C, and D, see Table 51. 0 – Condition C interrupts disabled. 1 – Condition C interrupts enabled. The Timer Interrupt D Enable bit controls whether an interrupt is generated on each occurrence of interrupt condition D. For an explanation of interrupt conditions A, B, C, and D, see Table 51. 0 – Condition D interrupts disabled. 1 – Condition D interrupts enabled. 23.5.9 Timer Interrupt Clear Register (TICLR) The TICLR register is a byte-wide, write-only register that allows software to clear the TAPND, TBPND, TCPND, and TDPND bits in the Timer Interrupt Control (TICTRL) register. Do not modify this register with instructions that access the register as a read-modify-write operand, such as the bit manipulation instructions. The register reads as FFh. The register format is shown below. 7 4 Reserved TACLR TBCLR TCCLR TDCLR 151 3 2 1 0 TDCLR TCCLR TBCLR TACLR The Timer Pending A Clear bit is used to clear the Timer Interrupt Source A Pending bit (TAPND) in the Timer Interrupt Control register (TICTL). 0 – Writing a 0 has no effect. 1 – Writing a 1 clears the TAPND bit. The Timer Pending A Clear bit is used to clear the Timer Interrupt Source B Pending bit (TBPND) in the Timer Interrupt Control register (TICTL). 0 – Writing a 0 has no effect. 1 – Writing a 1 clears the TBPND bit. The Timer Pending C Clear bit is used to clear the Timer Interrupt Source C Pending bit (TCPND) in the Timer Interrupt Control register (TICTL). 0 – Writing a 0 has no effect. 1 – Writing a 1 clears the TCPND bit. The Timer Pending D Clear bit is used to clear the Timer Interrupt Source D Pending bit (TDPND) in the Timer Interrupt Control register (TICTL). 0 – Writing a 0 has no effect. 1 – Writing a 1 clears the TDPND bit. www.national.com CP3BT10 TBPND CP3BT10 24.0 Versatile Timer Unit (VTU) The VTU contains four fully independent 16-bit timer sub- The VTU controls a total of eight I/O pins, each of which systems. Each timer subsystem can operate either as dual can function as either: 8-bit PWM timers, as a single 16-bit PWM timer, or as a 16— PWM output with programmable output polarity bit counter with 2 input capture channels. These timer sub— Capture input with programmable event detection and systems offers an 8-bit clock prescaler to accommodate a timer reset wide range of system frequencies. A flexible interrupt scheme with — Four separate system level interrupt requests The VTU offers the following features: — A total of 16 interrupt sources each with a separate in The VTU can be configured to provide: terrupt pending bit and interrupt enable bit — Eight fully independent 8-bit PWM channels 24.1 VTU FUNCTIONAL DESCRIPTION — Four fully independent 16-bit PWM channels — Eight 16-bit input capture channels The VTU is comprised of four timer subsystems. Each timer The VTU consists of four timer subsystems, each of subsystem contains an 8-bit clock prescaler, a 16-bit upwhich contains: counter, and two 16-bit registers. Each timer subsystem — A 16-bit counter controls two I/O pins which either function as PWM outputs — Two 16-bit capture / compare registers or capture inputs depending on the mode of operation. — An 8-bit fully programmable clock prescaler There are four system-level interrupt requests, one for each Each of the four timer subsystems can operate in the fol- timer subsystem. Each system-level interrupt request is lowing modes: controlled by four interrupt pending bits with associated en— Low power mode, i.e. all clocks are stopped able/disable bits. All four timer subsystems are fully inde— Dual 8-bit PWM mode pendent, and each may operate as a dual 8-bit PWM timer, — 16-bit PWM mode a 16-bit PWM timer, or as a dual 16-bit capture timer. — Dual 16-bit input capture mode Figure 66 shows the main elements of the VTU. 15 0 15 0 MODE 15 0 INTCTL IO1CTL 15 0 15 0 INTPND IO2CTL Timer Subsystem 2 Timer Subsystem 1 Timer Subsystem 3 7 7 Timer Subsystem 4 7 7 C1 PRSC C2 PRSC C3 PRSC C4RSC == Prescaler Counter == Prescaler Counter == Prescaler Counter == Prescaler Counter 15 0 15 0 15 0 15 0 Count1 Count2 Count3 Count4 Compare - Capture Compare - Capture Compare - Capture Compare - Capture PERCAP1 PERCAP2 PERCAP3 PERCAP4 Compare - Capture Compare - Capture Compare - Capture Compare - Capture DTYCAP1 DTYCAP2 DTYCAP3 DTYCAP4 I/O Control TIO1 I/O Control TIO2 I/O Control TIO3 I/O Control I/O Control TIO5 TIO4 I/O Control TIO6 I/O Control TIO7 I/O Control TIO8 DS088 Figure 66. Versatile Timer Unit Block Diagram www.national.com 152 Dual 8-bit PWM Mode The period of the PWM output waveform is determined by Each timer subsystem may be configured to generate two the value of the PERCAPx register. The TIOx output starts fully independent PWM waveforms on the respective TIOx at the default value as programmed in the IOxCTL.PxPOL pins. In this mode, the counter COUNTx is split and oper- bit. Once the counter value reaches the value of the period ates as two independent 8-bit counters. Each counter incre- register PERCAPx, the counter is cleared on the next counter increment. On the following increment from 00h to ments at the rate determined by the clock prescaler. 01h, the TIOx output will change to the opposite of the deEach of the two 8-bit counters may be started and stopped fault value. separately using the corresponding TxRUN bits. Once either of the two 8-bit timers is running, the clock prescaler The duty cycle of the PWM output waveform is controlled by starts counting. Once the clock prescaler counter value the DTYCAPx register value. Once the counter value reachmatches the value of the associated CxPRSC register field, es the value of the duty cycle register DTYCAPx, the PWM output TIOx changes back to its default value on the next COUNTx is incremented. counter increment. Figure 67 illustrates this concept. COUNTx 0A PERCAPx 0A 09 09 08 08 07 07 06 06 05 05 04 DTYCAPx 04 03 03 02 02 01 01 00 00 TxRUN = 1 TIOx (PxPOL = 0) TIOx (PxPOL = 1) DS089 Figure 67. VTU PWM Generation Reading the PERCAPx or DTYCAPx register will always return the most recent value written to it. The period time is determined by the following formula: PWM Period = (PERCAPx + 1) × (CxPRSC + 1) × TCLK The duty cycle in percent is calculated as follows: Duty Cycle = (DTYCAPx / (PERCAPx + 1)) × 100 If the duty cycle register (DTYCAPx) holds a value which is greater than the value held in the period register (PERCAPx) the TIOx output will remain at the opposite of its default value which corresponds to a duty cycle of 100%. If the duty cycle register (DTYCAPx) register holds a value of 00h, the TIOx output will remain at the default value which corresponds to a duty cycle of 0%, in which case the value in the PERCAPx register is irrelevant. This scheme allows the duty cycle to be programmed in a range from 0% to 100%. The counter registers can be written if both 8-bit counters are stopped. This allows software to preset the counters before starting, which can be used to generate PWM output waveforms with a phase shift relative to each other. If the counter is written with a value other than 00h, it will start incrementing from that value. The TIOx output will remain at its default value until the first 00h to 01h transition of the counter value occurs. If the counter is preset to values which are less than or equal to the value held in the period register (PERCAPx) the counter will count up until a match between the counter value and the PERCAPx register value occurs. The counter will then be cleared and continue counting up. Alternatively, the counter may be written with a value which is greater than the value held in the period register. In that case the counter will count up to FFh, then roll over to 00h. In any case, the TIOx pin always changes its state at the 00h to 01h transition of the counter. In order to allow fully synchronized updates of the period and duty cycle compare values, the PERCAPx and DTYCAPx registers are double buffered when operating in PWM mode. Therefore, if software writes to either the period or duty cycle register while either of the two PWM channels is enabled, the new value will not take effect until the counter Software may only write to the COUNTx register if both value matches the previous period value or the timer is TxRUN bits of a timer subsystem are clear. Any writes to the counter register while either timer is running will be ignored. stopped. 153 www.national.com CP3BT10 24.1.1 CP3BT10 The two I/O pins associated with a timer subsystem function as independent PWM outputs in the dual 8-bit PWM mode. If a PWM timer is stopped using its associated MODE.TxRUN bit the following actions result: Figure 69 illustrates the configuration of a timer subsystem while operating in 16-bit PWM mode. The numbering in Figure 69 refers to timer subsystem 1 but equally applies to the other three timer subsystems. The associated TIOx pin will return to its default value as defined by the IOxCTL.PxPOL bit. The counter will stop and will retain its last value. Any pending updates of the PERCAPx and DTYCAPx register will be completed. The prescaler counter will be stopped and reset if both MODE.TxRUN bits are cleared. 7 0 C1PRSC TMOD1 = 10 == Prescaler Counter T1RUN Figure 68 illustrates the configuration of a timer subsystem while operating in dual 8-bit PWM mode. The numbering in Figure 68 refers to timer subsystem 1 but equally applies to the other three timer subsystems. 15 0 [15:0] Restart Count1[15:0] Compare 7 0 PERCAP1[15:0] C1PRSC TMOD1 = 01 == Prescaler Counter Compare DTYCAP1[15:0] T2RUN T1RUN R Q R S 15 0 7 COUNT1[15:8] S 0 [15:8] Res Q [7:0] Res P2POL COUNT1[7:0] P1POL TIO2 Compare Compare PERCAP1[15:8] PERCAP1[7:0] Compare Compare DTYCAP1[15:8] DTYCAP1[7:0] TIO1 DS091 Figure 69. VTU 16-bit PWM Mode R Q R S 24.1.3 Q S P2POL P1POL TIO2 In capture mode the counter COUNTx operates as a 16-bit up-counter while the two TIOx pins associated with a timer subsystem operate as capture inputs. A capture event on the TIOx pins causes the contents of the counter register (COUNTx) to be copied to the PERCAPx or DTYCAPx registers respectively. TIO1 DS090 Figure 68. VTU Dual 8-Bit PWM Mode 24.1.2 Dual 16-Bit Capture Mode In addition to the two PWM modes, each timer subsystem may be configured to operate in an input capture mode which provides two 16-bit capture channels. The input capture mode can be used to precisely measure the period and duty cycle of external signals. 16-Bit PWM Mode Each of the four timer subsystems may be independently configured to provide a single 16-bit PWM channel. In this case the lower and upper bytes of the counter are concatenated to form a single 16-bit counter. Starting the counter is identical to the 16-bit PWM mode, i.e. setting the lower of the two MODE.TxRUN bits will start the counter and the clock prescaler. In addition, the capture event inputs are enabled once the MODE.TxRUN bit is set. Operation in 16-bit PWM mode is conceptually identical to the dual 8-bit PWM operation as outlined under Dual 8-bit PWM Mode on page 153. The 16-bit timer may be started or stopped with the lower MODE.TxRUN bit, i.e. T1RUN for timer subsystem 1. The TIOx capture inputs can be independently configured to detect a capture event on either a positive transition, a negative transition or both a positive and a negative transition. In addition, any capture event may be used to reset the counter COUNTx and the clock prescaler counter. This avoids the need for software to keep track of timer overflow conditions and greatly simplifies the direct frequency and duty cycle measurement of an external signal. The two TIOx outputs associated with a timer subsystem can be used to produce either two identical PWM waveforms or two PWM waveforms of opposite polarities. This can be accomplished by setting the two PxPOL bits of the respective timer subsystem to either identical or opposite values. www.national.com 154 7 0 C1PRSC TMOD1=11 == Prescaler Counter 24.1.5 Interrupts The VTU has a total of 16 interrupt sources, four for each of the four timer subsystems. All interrupt sources have a pending bit and an enable bit associated with them. All interrupt pending bits are denoted IxAPD through IxDPD where “x” relates to the specific timer subsystem. There is one system level interrupt request for each of the four timer subsystems. Figure 71 illustrates the interrupt structure of the versatile timer module. T1RUN I1AEN 15 0 I1BEN 15:0 Count1[15:0] Restart I1CEN I1DEN Compare PERCAP1[15:0] I1APD Compare I1BPD DTYCAP1[15:0] I1CPD System Interrupt Request 1 I1DPD cap cap rst rst 2 0 2 C1EDG I4AEN 0 C2EDG I4BEN TIO1 TIO2 I4CEN DS092 Figure 70. 24.1.4 I4DEN VTU Dual 16-bit Capture Mode I4APD Low Power Mode I4BPD In case a timer subsystem is not used, software can place it in a low-power mode. All clocks to a timer subsystem are stopped and the counter and prescaler contents are frozen once low-power mode is entered. Software may continue to write to the MODE, INTCTL, IOxCTL, and CLKxPS registers. Write operations to the INTPND register are allowed; but if a timer subsystem is in low-power mode, its associated interrupt pending bits cannot be cleared. Software cannot write to the COUNTx, PERCAPx, and DTYCAPx registers of a timer subsystem while it is in low-power mode. All registers can be read at any time. Table 54 Pending Flag System Interrupt Request 4 I4CPD I4DPD DS093 Figure 71. VTU Interrupt Request Structure Each of the timer pending bits - IxAPD through IxDPD - is set by a specific hardware event depending on the mode of operation, i.e., PWM or Capture mode. Table 54 outlines the specific hardware events relative to the operation mode which cause an interrupt pending bit to be set. VTU Interrupt Sources Dual 8-bit PWM Mode 16-bit PWM Mode Capture Mode IxAPD Low Byte Duty Cycle match Duty Cycle match Capture to PERCAPx IxBPD Low Byte Period match Period match Capture to DTYCAPx IxCPD High Byte Duty Cycle match N/A Counter Overflow IxDPD High Byte Period match N/A N/A 24.1.6 ISE Mode operation isters will be frozen; in capture mode, all further capture The VTU supports breakpoint operation of the In-System- events are disabled. Once FREEZE becomes inactive, Emulator (ISE). If FREEZE is asserted, all timer counter counting will resume from the previous value and the capclocks will be inhibited and the current value of the timer reg- ture input events are re-enabled. 155 www.national.com CP3BT10 Figure 70 illustrates the configuration of a timer subsystem while operating in capture mode. The numbering in Figure 70 refers to timer subsystem 1 but equally applies to the other three timer subsystems. CP3BT10 24.2 VTU REGISTERS 24.2.1 Mode Control Register (MODE) The VTU contains a total of 19 user accessible registers, as The MODE register is a word-wide read/write register which listed in Table 55. All registers are word-wide and are initial- controls the mode selection of all four timer subsystems. ized to a known value upon reset. All software accesses to The register is clear after reset. the VTU registers must be word accesses. 7 Table 55 VTU Registers 5 4 3 2 1 0 TMOD2 T4RUN T3RUN TMOD1 T2RUN T1RUN Name Address Description MODE FF FF80h Mode Control Register IO1CTL FF FF82h I/O Control Register 1 IO2CTL FF FF84h I/O Control Register 2 INTCTL FF FF86h Interrupt Control Register INTPND FF FF88h Interrupt Pending Register CLK1PS FF FF8Ah Clock Prescaler Register 1 CLK2PS FF FF98h Clock Prescaler Register 2 COUNT1 FF FF8Ch Counter 1 Register PERCAP1 FF FF8Eh Period/Capture 1 Register DTYCAP1 FF FF90h Duty Cycle/Capture 1 Register COUNT2 FF FF92h Counter 2 Register PERCAP2 FF FF94h Period/Capture 2 Register DTYCAP2 FF FF96h Duty Cycle/Capture 2 Register COUNT3 FF FF9Ah Counter 3 Register PERCAP3 FF FF9Ch Period/Capture 3 Register DTYCAP3 FF FF9Eh Duty Cycle/Capture 3 Register COUNT4 FF FFA0h Counter 4 Register PERCAP4 FF FFA2h Period/Capture 4 Register DTYCAP4 FF FFA4h Duty Cycle/Capture 4 Register www.national.com 6 15 14 13 12 11 10 9 8 TMOD4 T8RUN T7RUN TMOD3 T6RUN T5RUN TxRUN TMODx 156 The Timer Run bit controls whether the corresponding timer is stopped or running. If set, the associated counter and clock prescaler is started depending on the mode of operation. Once set, the clock to the clock prescaler and the counter are enabled and the counter will increment each time the clock prescaler counter value matches the value defined in the associated clock prescaler field (CxPRSC). 0 – Timer stopped. 1 – Timer running. The Timer System Operating Mode field enables or disables the Timer Subsystem and defines its operating mode. 00 – Low-Power Mode. All clocks to the counter subsystem are stopped. The counter is stopped regardless of the value of the TxRUN bits. Read operations to the Timer Subsystem will return the last value; software must not perform any write operations to the Timer Subsystem while it is disabled since those will be ignored. 01 – Dual 8-bit PWM mode. Each 8-bit counter may individually be started or stopped via its associated TxRUN bit. The TIOx pins will function as PWM outputs. 10 – 16-bit PWM mode. The two 8-bit counters are concatenated to form a single 16-bit counter. The counter may be started or stopped with the lower of the two TxRUN bits, i.e. T1RUN, T3RUN, T5RUN, and T7RUN. The TIOx pins will function as PWM outputs. 11 – Capture Mode. Both 8-bit counters are concatenated and operate as a single 16-bit counter. The counter may be started or stopped with the lower of the two TxRUN bits, i.e., T1RUN, T3RUN, T5RUN, and T7RUN. The TIOx pins will function as capture inputs. I/O Control Register 1 (IO1CTL) 24.2.3 The I/O Control Register 1 (IO1CTL) is a word-wide read/ write register. The register controls the function of the I/O pins TIO1 through TIO4 depending on the selected mode of operation. The register is clear after reset. 7 6 P2POL 15 P4POL CxEDG 4 3 C2EDG 14 P1POL 12 C4EDG 2 11 P3POL The IO2CTL register is a word-wide read/write register. The register controls the functionality of the I/O pins TIO5 through TIO8 depending on the selected mode of operation. The register is cleared at reset. 0 C1EDG 10 I/O Control Register 2 (IO2CTL) 7 6 P6POL 8 C3EDG 15 4 C6EDG 14 P8POL 3 2 0 P5POL 12 C8EDG 11 C5EDG 10 P7POL 8 C7EDG The Capture Edge Control field specifies the The functionality of the bit fields of the IO2CTL register is polarity of a capture event and the reset of the identical to the ones described in the IO1CTL register seccounter. The value of this three bit field has no tion. effect while operating in PWM mode. 24.2.4 Interrupt Control Register (INTCTL) CxEDG Capture Counter Reset The INTCTL register is a word-wide read/write register. It 000 Rising edge No 001 Falling edge No 010 Rising edge Yes 011 Falling edge Yes 100 Both edges No 101 Both edges Rising edge 110 Both edges Falling edge 111 Both edges Both edges contains the interrupt enable bits for all 16 interrupt sources of the VTU. Each interrupt enable bit corresponds to an interrupt pending bit located in the Interrupt Pending Register (INTPND). All INTCTL register bits are solely under software control. The register is clear after reset. 7 6 5 4 3 2 1 0 I2DEN I2CEN I2BEN I2AEN I1DEN I1CEN I1BEN I1AEN PxPOL 15 14 13 12 11 10 9 8 I4DEN I4CEN I4BEN I4AEN I3DEN I3CEN I3BEN I3AEN The PWM Polarity bit selects the output polarity. While operating in PWM mode the bit specifies the polarity of the corresponding IxAEN PWM output (TIOx). Once a counter is stopped, the output will assume the value of PxPOL, i.e., its initial value. The PxPOL bit has no effect while operating in capture mode. 0 – The PWM output goes high at the 00h to 01h transition of the counter and will go low once the counter value matches the duty cycle value. 1 – The PWM output goes low at the 00h to IxBEN 01h transition of the counter and will go high once the counter value matches the duty cycle value. 157 The Timer x Interrupt A Enable bit controls interrupt requests triggered on the corresponding IxAPD bit being set. The associated IxAPD bit will be updated regardless of the value of the IxAEN bit. 0 – Disable system interrupt request for the IxAPD pending bit. 1 – Enable system interrupt request for the IxAPD pending bit. The Timer x Interrupt B Enable bit controls interrupt requests triggered on the corresponding IxBPD bit being set. The associated IxBPD bit will be updated regardless of the value of the IxBEN bit. 0 – Disable system interrupt request for the IxBPD pending bit. 1 – Enable system interrupt request for the IxBPD pending bit. www.national.com CP3BT10 24.2.2 CP3BT10 IxCEN The Timer x Interrupt C Enable bit controls interrupt requests triggered on the corresponding IxCPD bit being set. The associated IxCPD bit will be updated regardless of the value of the IxCEN bit. 0 – Disable system interrupt request for the IxCPD pending bit. 1 – Enable system interrupt request for the IxCPD pending bit. Timer x Interrupt D Enable bit controls interrupt requests triggered on the corresponding IxDPD bit being set. The associated IxDPD bit will be updated regardless of the value of the IxDEN bit. 0 – Disable system interrupt request for the IxDPD pending bit. 1 – Enable system interrupt request for the IxDPD pending bit. IxDEN 24.2.5 IxDPD 24.2.6 The CLK1PS register is a word-wide read/write register. The register is split into two 8-bit fields called C1PRSC and C2PRSC. Each field holds the 8-bit clock prescaler compare value for timer subsystems 1 and 2 respectively. The register is cleared at reset. 15 C1PRSC 6 5 4 3 2 1 0 I2DPD I2CPD I2BPD I2APD I1DPD I1CPD I1BPD I1APD 14 13 12 11 10 9 8 I4DPD I4CPD I4BPD I4APD I3DPD I3CPD I3BPD I3APD IxAPD IxBPD IxCPD 8 7 C2PRSC C2PRSC 15 Clock Prescaler Register 1 (CLK1PS) 0 C1PRSC Interrupt Pending Register (INTPND) The INTPND register is a word-wide read/write register which contains all 16 interrupt pending bits. There are four interrupt pending bits called IxAPD through IxDPD for each timer subsystem. Each interrupt pending bit is set by a hardware event and can be cleared if software writes a 1 to the bit position. The value will remain unchanged if a 0 is written to the bit position. All interrupt pending bits are cleared (0) upon reset. 7 The Timer x Interrupt D Pending bit indicates that an interrupt condition for the related timer subsystem has occurred. Table 54 on page 155 lists the hardware condition which causes this bit to be set. 0 – No interrupt pending. 1 – Timer interrupt condition occurred. The Timer x Interrupt A Pending bit indicates that an interrupt condition for the related timer subsystem has occurred. Table 54 on page 155 lists the hardware condition which causes this bit to be set. 0 – No interrupt pending. 1 – Timer interrupt condition occurred. The Timer x Interrupt B Pending bit indicates that an interrupt condition for the related timer subsystem has occurred. Table 54 on page 155 lists the hardware condition which causes this bit to be set. 0 – No interrupt pending. 1 – Timer interrupt condition occurred. The Timer x Interrupt C Pending bit indicates that an interrupt condition for the related timer subsystem has occurred. Table 54 on page 155 lists the hardware condition which causes this bit to be set. 0 – No interrupt pending. 1 – Timer interrupt condition occurred. www.national.com 24.2.7 The Clock Prescaler 1 Compare Value field holds the 8-bit prescaler value for timer subsystem 1. The counter of timer subsystem is incremented each time when the clock prescaler compare value matches the value of the clock prescaler counter. The division ratio is equal to (C1PRSC + 1). For example, 00h is a ratio of 1, and FFh is a ratio of 256. The Clock Prescaler 2 Compare Value field holds the 8-bit prescaler value for timer subsystem 2. The counter of timer subsystem is incremented each time when the clock prescaler compare value matches the value of the clock prescaler counter. The division ratio is equal to (C2PRSC + 1). Clock Prescaler Register 2 (CLK2PS) The Clock Prescaler Register 2 (CLK2PS) is a word-wide read/write register. The register is split into two 8-bit fields called C3PRSC and C4PRSC. Each field holds the 8-bit clock prescaler compare value for timer subsystems 3 and 4 respectively. The register is cleared at reset. 15 8 C4PRSC C3PRSC C4PRSC 158 7 0 C3PRSC The Clock Prescaler 3 Compare Value field holds the 8-bit prescaler value for timer subsystem 3. The counter of timer subsystem is incremented each time when the clock prescaler compare value matches the value of the clock prescaler counter. The division ratio is equal to (C3PRSC + 1). The Clock Prescaler 4 Compare Value field holds the 8-bit prescaler value for timer subsystem 4. The counter of timer subsystem is incremented each time when the clock prescaler compare value matches the value of the clock prescaler counter. The division ratio is equal to (C4PRSC + 1). Counter Register n (COUNTx) 24.2.10 Duty Cycle/Capture Register n (DTYCAPx) The Counter (COUNTx) registers are word-wide read/write registers. There are a total of four registers called COUNT1 through COUNT4, one for each of the four timer subsystems. Software may read the registers at any time. Reading the register will return the current value of the counter. The register may only be written if the counter is stopped (i.e. if both TxRUN bits associated with a timer subsystem are clear). The registers are cleared at reset. 15 0 CNTx 24.2.9 The Duty Cycle/Capture (DTYCAPx) registers are wordwide read/write registers. There are a total of four registers called DTYCAP1 through DTYCAP4, one for each timer subsystem. The registers hold the period compare value in PWM mode or the counter value at the time the last associated capture event occurred. In PWM mode, the register is double buffered. If a new duty cycle compare value is written while the counter is running, the write will not take effect until the counter value matches the previous period compare value or until the counter is stopped. The update takes effect on period boundaries only. Reading may take place at any time and will return the most recent value which was written. The DTYCAPx registers are cleared at reset. Period/Capture Register n (PERCAPx) The PERCAPx registers are word-wide read/write registers. There are a total of four registers called PERCAP1 through PERCAP4, one for each timer subsystem. The registers hold the period compare value in PWM mode of the counter value at the time the last associated capture event occurred. In PWM mode the register is double buffered. If a new period compare value is written while the counter is running, the write will not take effect until counter value matches the previous period compare value or until the counter is stopped. Reading may take place at any time and will return the most recent value which was written. The PERCAPx registers are cleared at reset. 15 15 0 DCAPx 0 PCAPx 159 www.national.com CP3BT10 24.2.8 CP3BT10 25.0 Register Map Table 56 is a detailed memory map showing the specific memory address of the memory, I/O ports, and registers. The table shows the starting address, the size, and a brief description of each memory block and register. For detailed information on using these memory locations, see the applicable sections in the data sheet. All addresses not listed in the table are reserved and must not be read or written. An attempt to access an unlisted address will have unpredictable results. the byte-wide and word-wide registers reside at word boundaries (even addresses). Therefore, each byte-wide register uses only the lowest eight bits of the internal data bus. Most device registers are read/write registers. However, some registers are read-only or write-only, as indicated in the table. An attempt to read a write-only register or to write a read-only register will have unpredictable results. When software writes to a register in which one or more bits Each byte-wide register occupies a single address and can are reserved, it must write a zero to each reserved bit unless be accessed only in a byte-wide transaction. Each word- indicated otherwise in the description of the register. Readwide register occupies two consecutive memory addresses ing a reserved bit returns an undefined value. and can be accessed only in a word-wide transaction. Both Table 56 Detailed Device Mapping Register Name Size Address Access Type Bluetooth LLC Registers PLN Byte 0E F180h Write-Only WHITENING_CHANNEL_SELECTION Byte 0E F181h Write-Only SINGLE_FREQUENCY_SELECTION Byte 0E F182h Write-Only LN_BT_CLOCK_0 Byte 0E F198h Read-Only LN_BT_CLOCK_1 Byte 0E F199h Read-Only LN_BT_CLOCK_2 Byte 0E F19Ah Read-Only LN_BT_CLOCK_3 Byte 0E F19Bh Read-Only RX_CN Byte 0E F19Ch Read-Only TX_CN Byte 0E F19Dh Read-Only AC_ACCEPTLVL Word 0E F19Eh Write-Only LAP_ACCEPTLVL Byte 0E F1A0h Write-Only RFSYNCH_DELAY Byte 0E F1A1h Write-Only SPI_READ Word 0E F1A2h Read-Only SPI_MODE_CONFIG Byte 0E F1A4h Write-Only M_COUNTER_0 Byte 0E F1A6h Read/Write M_COUNTER_1 Byte 0E F1A7h Read/Write M_COUNTER_2 Byte 0E F1A8h Read/Write N_COUNTER_0 Byte 0E F1AAh Write-Only N_COUNTER_1 Byte 0E F1ABh Write-Only BT_CLOCK_WR_0 Byte 0E F1ACh Write-Only BT_CLOCK_WR_1 Byte 0E F1ADh Write-Only BT_CLOCK_WR_2 Byte 0E F1AEh Write-Only BT_CLOCK_WR_3 Byte 0E F1AFh Write-Only www.national.com 160 Value After Reset Comments Address Access Type WTPTC_1SLOT Word 0E F1B0h Write-Only WTPTC_3SLOT Word 0E F1B2h Write-Only WTPTC_5SLOT Word 0E F1B4h Write-Only SEQ_RESET Byte 0E F1B6h Write-Only SEQ_CONTINUE Byte 0E F1B7h Write-Only RX_STATUS Byte 0E F1B8h Read-Only CHIP_ID Byte 0E F1BAh Read-Only INT_VECTOR Byte 0E F1BCh Read-Only SYSTEM_CLK_EN Byte 0E F1BEh Write-Only LINKTIMER_WR_RD Word 0E F1C0h Read-Only LINKTIMER_SELECT Byte 0E F1C2h Read-Only LINKTIMER_STATUS_EXP_FLAG Byte 0E F1C4h Read-Only LINKTIMER_STATUS_RD_WR_FLAG Byte 0E F1C5h Read-Only LINKTIMER_ADJUST_PLUS Byte 0E F1C6h Read-Only LINKTIMER_ADJUST_MINUS Byte 0E F1C7h Read-Only SLOTTIMER_WR_RD Byte 0E F1C8h Read-Only Value After Reset Comments USB Node Registers MCNTRL Byte FF FD80h Read/Write 00h FAR Byte FF FD88h Read/Write 00h NFSR Byte FF FD8Ah Read/Write 00h MAEV Byte FF FD8Ch Read/Write 00h MAMSK Byte FF FD8Eh Read/Write 00h ALTEV Byte FF FD90h Read/Write 00h ALTMSK Byte FF FD92h Read/Write 00h TXEV Byte FF FD94h Read/Write 00h TXMSK Byte FF FD96h Read/Write 00h RXEV Byte FF FD98h Read/Write 00h RXMSK Byte FF FD9Ah Read/Write 00h NAKEV Byte FF FD9Ch Read/Write 00h NAKMSK Byte FF FD9Eh Read/Write 00h FWEV Byte FF FDA0h Read/Write 00h FWMSK Byte FF FDA2h Read/Write 00h FNH Byte FF FDA4h Read/Write C0h FNL Byte FF FDA6h Read/Write 00h DMACNTRL Byte FF FDA8h Read/Write 00h 161 www.national.com CP3BT10 Size Register Name CP3BT10 Size Address Access Type Value After Reset DMAEV Byte FF FDAAh Read/Write 00h DMAMSK Byte FF FDACh Read/Write 00h MIR Byte FF FDAEh Read/Write 1Fh DMACNT Byte FF FDB0h Read/Write 00h DMAERR Byte FF FDB2h Read/Write 00h EPC0 Byte FF FDC0h Read/Write 00h TXD0 Byte FF FDC2h Read/Write TXS0 Byte FF FDC4h Read/Write 08h TXC0 Byte FF FDC6h Read/Write 00h RXD0 Byte FF FDCAh Read/Write XXh RXS0 Byte FF FDCCh Read/Write 00h RXC0 Byte FF FDCEh Read/Write 00h EPC1 Byte FF FDD0h Read/Write 00h TXD1 Byte FF FDD2h Read/Write XXh TXS1 Byte FF FDD4h Read/Write 1Fh TXC1 Byte FF FDD6h Read/Write 00h EPC2 Byte FF FDD8h Read/Write 00h RXD1 Byte FF FDDAh Read/Write XXh RXS1 Byte FF FDDCh Read/Write 00h RXC1 Byte FF FDDEh Read/Write 00h EPC3 Byte FF FDE0h Read/Write 00h TXD2 Byte FF FDE2h Read/Write XXh TXS2 Byte FF FDE4h Read/Write 1Fh TXC2 Byte FF FDE6h Read/Write 00h EPC4 Byte FF FDE8h Read/Write 00h RXD2 Byte FF FDEAh Read/Write XXh RXS2 Byte FF FDECh Read/Write 00h RXC2 Byte FF FDEEh Read/Write 00h EPC5 Byte FF FDF0h Read/Write 00h TXD3 Byte FF FDF2h Read/Write XXh TXS3 Byte FF FDF4h Read/Write 1Fh TXC3 Byte FF FDF6h Read/Write 00h EPC6 Byte FF FDF8h Read/Write 00h RXD3 Byte FF FDFAh Read/Write XXh RXS3 Byte FF FDFCh Read/Write 00h RXC3 Byte FF FDFEh Read/Write 00h Register Name www.national.com 162 Comments Size Address Access Type Value After Reset Comments DMA Controller ADCA0 Double Word FF F800h Read/Write 0000 0000h ADRA0 Double Word FF F804h Read/Write 0000 0000h ADCB0 Double Word FF F808h Read/Write 0000 0000h ADRB0 Double Word FF F80Ch Read/Write 0000 0000h BLTC0 Word FF F810h Read/Write 0000h BLTR0 Word FF F814h Read/Write 0000h DMACNTL0 Word FF F81Ch Read/Write 0000h DMASTAT0 Byte FF F81Eh Read/Write 00h ADCA1 Double Word FF F820h Read/Write 0000 0000h ADRA1 Double Word FF F824h Read/Write 0000 0000h ADCB1 Double Word FF F828h Read/Write 0000 0000h ADRB1 Double Word FF F82Ch Read/Write 0000 0000h BLTC1 Word FF F830h Read/Write 0000h BLTR1 Word FF F834h Read/Write 0000h DMACNTL1 Word FF F83Ch Read/Write 0000h DMASTAT1 Byte FF F83Eh Read/Write 00h ADCA2 Double Word FF F840h Read/Write 0000 0000h ADRA2 Double Word FF F844h Read/Write 0000 0000h ADCB2 Double Word FF F848h Read/Write 0000 0000h ADRB2 Double Word FF F84Ch Read/Write 0000 0000h BLTC2 Word FF F850h Read/Write 0000h BLTR2 Word FF F854h Read/Write 0000h DMACNTL2 Word FF F85Ch Read/Write 0000h DMASTAT2 Byte FF F85Eh Read/Write 00h Double Word FF F860h Read/Write 0000 0000h ADCA3 163 www.national.com CP3BT10 Register Name CP3BT10 Size Address Access Type Value After Reset ADRA3 Double Word FF F864h Read/Write 0000 0000h ADCB3 Double Word FF F868h Read/Write 0000 0000h ADRB3 Double Word FF F86Ch Read/Write 0000 0000h BLTC3 Word FF F870h Read/Write 0000h BLTR3 Word FF F874h Read/Write 0000h DMACNTL3 Word FF F87Ch Read/Write 0000h DMASTAT3 Byte FF F87Eh Read/Write 00h Register Name Bus Interface Unit BCFG Byte FF F900h Read/Write 07h IOCFG Word FF F902h Read/Write 069Fh SZCFG0 Word FF F904h Read/Write 069Fh SZCFG1 Word FF F906h Read/Write 069Fh SZCFG2 Word FF F908h Read/Write 069Fh System Configuration MCFG Byte FF F910h Read/Write 00h DBGCFG Byte FF F912h Read/Write 00h MSTAT Byte FF F914h Read Only ENV2:0 pins Flash Program Memory Interface FMIBAR Word FF F940h Read/Write 0000h FMIBDR Word FF F942h Read/Write 0000h FM0WER Word FF F944h Read/Write 0000h FM1WER Word FF F946h Read/Write 0000h FMCTRL Word FF F94Ch Read/Write 0000h FMSTAT Word FF F94Eh Read/Write 0000h FMPSR Byte FF F950h Read/Write 04h FMSTART Byte FF F952h Read/Write 18h FMTRAN Byte FF F954h Read/Write 30h FMPROG Byte FF F956h Read/Write 16h FMPERASE Byte FF F958h Read/Write 04h FMMERASE0 Byte FF F95Ah Read/Write EAh www.national.com 164 Comments Address Access Type Value After Reset FMEND Byte FF F95Eh Read/Write 18h FMMEND Byte FF F960h Read/Write 3Ch FMRCV Byte FF F962h Read/Write 04h FMAR0 Word FF F964h Read Only FMAR1 Word FF F966h Read Only FMAR2 Word FF F968h Read Only Comments Flash Data Memory Interface FSMIBAR Word FF F740h Read/Write 0000h FSMIBDR Word FF F742h Read/Write 0000h FSM0WER Word FF F744h Read/Write 0000h FSMCTRL Word FF F74Ch Read/Write 0000h FSMSTAT Word FF F74Eh Read/Write 0000h FSMPSR Byte FF F750h Read/Write 04h FSMSTART Byte FF F752h Read/Write 18h FSMTRAN Byte FF F754h Read/Write 30h FSMPROG Byte FF F756h Read/Write 16h FSMPERASE Byte FF F758h Read/Write 04h FSMMERASE0 Byte FF F75Ah Read/Write EAh FSMEND Byte FF F75Eh Read/Write 18h FSMMEND Byte FF F760h Read/Write 3Ch FSMRCV Byte FF F762h Read/Write 04h FSMAR0 Word FF F764h Read Only FSMAR1 Word FF F766h Read Only FSMAR2 Word FF F768h Read Only CVSD/PCM Converter CVSDIN Word FF FC20h Write Only 0000h CVSDOUT Word FF FC22h Read Only 0000h PCMIN Word FF FC24h Write Only 0000h PCMOUT Word FF FC26h Read Only 0000h LOGIN Byte FF FC28h Write Only 0000h LOGOUT Byte FF FC2Ah Read Only 0000h LINEARIN Word FF FC2Ch Write Only 0000h LINEAROUT Word FF FC2Eh Read Only 0000h 165 www.national.com CP3BT10 Size Register Name CP3BT10 Size Address Access Type Value After Reset CVCTRL Word FF FC30h Read/Write 0000h CVSTAT Word FF FC32h Read Only 0000h CVTEST Word FF FC34h Read/Write 0000h CVRADD Word FF FC36h Read/Write 0000h CVRDAT Word FF FC38h Read/Write 0000h CVDECOUT Word FF FC3Ah Read Only 0000h CVENCIN Word FF FC3Ch Read Only 0000h CVENCPR Word FF FC3Eh Read Only 0000h Register Name Comments Triple Clock + Reset CRCTRL Byte FF FC40h Read/Write 00X0 0110b PRSFC Byte FF FC42h Read/Write 4Fh PRSSC Byte FF FC44h Read/Write B6h PRSAC Byte FF FC46h Read/Write FFh Power Management PMMCR Byte FF FC60h Read/Write 00h PMMSR Byte FF FC62h Read/Write 0000 0XXXb Multi-Input Wake-Up WKEDG Word FF FC80h Read/Write 00h WKENA Word FF FC82h Read/Write 00h WKICTL1 Word FF FC84h Read/Write 00h WKICTL2 Word FF FC86h Read/Write 00h WKPND Word FF FC88h Read/Write 00h WKPCL Word FF FC8Ah Write Only XXh WKIENA Word FF FC8Ch Read/Write 00h General-Purpose I/O ports PBALT Byte FF FB00h Read/Write 00h PBDIR Byte FF FB02h Read/Write 00h PBDIN Byte FF FB04h Read Only XXh PBDOUT Byte FF FB06h Read/Write XXh PBWPU Byte FF FB08h Read/Write 00h www.national.com 166 Bits may only be set; writing 0 has no effect. Address Access Type Value After Reset PBHDRV Byte FF FB0Ah Read/Write 00h PBALTS Byte FF FB0Ch Read/Write 00h PCALT Byte FF FB10h Read/Write 00h PCDIR Byte FF FB12h Read Only 00h PCDIN Byte FF FB14h Read/Write XXh PCDOUT Byte FF FB16h Read/Write XXh PCWPU Byte FF FB18h Read/Write 00h PCHDRV Byte FF FB1Ah Read/Write 00h PCALTS Byte FF FB1Ch Read/Write 00h Comments I/O ports with Alternate Functions PGALT Byte FF FCA0h Read/Write 00h PGDIR Byte FF FCA2h Read/Write 00h PGDIN Byte FF FCA4h Read Only XXh PGDOUT Byte FF FCA6h Read/Write XXh PGWPU Byte FF FCA8h Read/Write 00h PGHDRV Byte FF FCAAh Read/Write 00h PGALTS Byte FF FCACh Read/Write 00h PHALT Byte FF FCC0h Read/Write 00h PHDIR Byte FF FCC2h Read/Write 00h PHDIN Byte FF FCC4h Read Only XXh PHDOUT Byte FF FCC6h Read/Write XXh PHWPU Byte FF FCC8h Read/Write 00h PHHDRV Byte FF FCCAh Read/Write 00h PHALTS Byte FF FCCCh Read/Write 00h PIALT Byte FF FEE0h Read/Write 00h PIDIR Byte FF FEE2h Read/Write 00h PIDIN Byte FF FEE4h Read Only XXh PIDOUT Byte FF FEE6h Read/Write XXh PIWPU Byte FF FEE8h Read/Write 00h PIHDRV Byte FF FEEAh Read/Write 00h PIALTS Byte FF FEECh Read/Write 00h 167 www.national.com CP3BT10 Size Register Name CP3BT10 Register Name Size Access Type Address Value After Reset Comments Advanced Audio Interface ARFR Word FF FD40h Read Only 0000h ARDR0 Word FF FD42h Read Only 0000h ARDR1 Word FF FD44h Read Only 0000h ARDR2 Word FF FD46h Read Only 0000h ARDR3 Word FF FD48h Read Only 0000h ATFR Word FF FD4Ah Write Only XXXXh ATDR0 Word FF FD4Ch Write Only 0000h ATDR1 Word FF FD4Eh Write Only 0000h ATDR2 Word FF FD50h Write Only 0000h ATDR3 Word FF FD52h Write Only 0000h AGCR Word FF FD54h Read/Write 0000h AISCR Word FF FD56h Read/Write 0000h ARSCR Word FF FD58h Read/Write 0004h ATSCR Word FF FD5Ah Read/Write F003h ACCR Word FF FD5Ch Read/Write 0000h ADMACR Word FF FD5Eh Read/Write 0000h Interrupt Control Unit IVCT Byte FF FE00h Read Only 10h NMISTAT Byte FF FE02h Read Only 00h EXNMI Byte FF FE04h Read/Write XXXX 00X0b ISTAT0 Word FF FE0Ah Read Only 0000h ISTAT1 Word FF FE0Ch Read Only 0000h IENAM0 Word FF FE0Eh Read/Write 0000h IENAM1 Word FF FE10h Read/Write 0000h Fixed Addr. UART UTBUF Byte FF FE40h Read/Write XXh URBUF Byte FF FE42h Read Only XXh UICTRL Byte FF FE44h Read/Write 01h USTAT Byte FF FE46h Read only 00h UFRS Byte FF FE48h Read/Write 00h UMDSL1 Byte FF FE4Ah Read/Write 00h www.national.com 168 Bits 0:1 read only Address Access Type Value After Reset UBAUD Byte FF FE4Ch Read/Write 00h UPSR Byte FF FE4Eh Read/Write 00h UOVR Byte FF FE50h Read/Write 00h UMDSL2 Byte FF FE52h Read/Write 00h USPOS Byte FF FE54h Read/Write 06h Comments Microwire/SPI interface MWDAT Word FF FE60h Read/Write XXXXh MWCTL1 Word FF FE62h Read/Write 0000h MWSTAT Word FF FE64h Read Only All implemented bits are 0 ACCESS.bus ACBSDA Byte FF FEC0h Read/Write XXh ACBST Byte FF FEC2h Read/Write 00h ACBCST Byte FF FEC4h Read/Write 00h ACBCTL1 Byte FF FEC6h Read/Write 00h ACBADDR Byte FF FEC8h Read/Write XXh ACBCTL2 Byte FF FECAh Read/Write 00h ACBADDR2 Byte FF FECCh Read/Write XXh ACBCTL3 Byte FF FECEh Read/Write 00h Timing and Watchdog TWCFG Byte FF FF20h Read/Write 00h TWCP Byte FF FF22h Read/Write 00h TWMT0 Word FF FF24h Read/Write FFFFh T0CSR Byte FF FF26h Read/Write 00h WDCNT Byte FF FF28h Write Only 0Fh WDSDM Byte FF FF2Ah Write Only 5Fh Multi-Function Timer TCNT1 Word FF FF40h Read/Write XXh TCRA Word FF FF42h Read/Write XXh TCRB Word FF FF44h Read/Write XXh 169 www.national.com CP3BT10 Size Register Name CP3BT10 Size Address Access Type Value After Reset TCNT2 Word FF FF46h Read/Write XXh TPRSC Byte FF FF48h Read/Write 00h TCKC Byte FF FF4Ah Read/Write 00h TCTRL Byte FF FF4Ch Read/Write 00h TICTL Byte FF FF4Eh Read/Write 00h TICLR Byte FF FF50h Read/Write 00h Register Name Versatile Timer Unit MODE Word FF FF80h Read/Write 0000h IO1CTL Word FF FF82h Read/Write 0000h IO2CTL Word FF FF84h Read/Write 0000h INTCTL Word FF FF86h Read/Write 0000h INTPND Word FF FF88h Read/Write 0000h CLK1PS Word FF FF8Ah Read/Write 0000h COUNT1 Word FF FF8Ch Read/Write 0000h PERCAP1 Word FF FF8Eh Read/Write 0000h DTYCAP1 Word FF FF90h Read/Write 0000h COUNT2 Word FF FF92h Read/Write 0000h PERCAP2 Word FF FF94h Read/Write 0000h DTYCAP2 Word FF FF96h Read/Write 0000h CLK2PS Word FF FF98h Read/Write 0000h COUNT3 Word FF FF9Ah Read/Write 0000h PERCAP3 Word FF FF9Ch Read/Write 0000h DTYCAP3 Word FF FF9Eh Read/Write 0000h COUNT4 Word FF FFA0h Read/Write 0000h PERCAP4 Word FF FFA2h Read/Write 0000h DTYCAP4 Word FF FFA4h Read/Write 0000h www.national.com 170 Comments The following tables show the functions of the bit fields of the device registers. For more information on using these registers, see the detailed description of the applicable function elsewhere in this data sheet. Bluetooth LLC Registers 7 6 5 4 PLN Reserved WHITENING_ CHANNEL_ SELECTION Reserved SINGLE_FREQUENCY _SELECTION Reserved 3 2 CHANNEL_ SELECTION[1:0] LN_BT_CLOCK_1 LN_BT_CLOCK[15:8] LN_BT_CLOCK_2 LN_BT_CLOCK[23:16] LN_BT_CLOCK_3 Reserved LN_BT_CLOCK[27:23] RX_CN Reserved RX_CN[6:0] TX_CN Reserved TX_CN[6:0] AC_ACCEPTLVL[7:0] AC_ACCEPTLVL[7:0] AC_ACCEPTLVL[15:8] Reserved AC_ACCEPTLVL[9:8] LAP_ACCEPTLVL Reserved LAP_ACCEPTLVL[5:0] RFSYNCH_DELAY Reserved RFSYNCH_DELAY[5:0] SPI_READ[7:0] SPI_READ[7:0] SPI_READ[15:8] SPI_READ[15:8] Reserved SPI_CLK_CONF[1:0] SPI_LEN_ SPI_DATA SPI_DATA SPI_DATA_ CONF _CONF3 _CONF2 CONF1 M_COUNTER_0 M_COUNTER[7:0] M_COUNTER_1 M_COUNTER[15:8] Reserved M_COUNTER[20:16] N_COUNTER_0 N_COUNTER[7:0] N_COUNTER_1 Reserved N_COUNTER[9:8] BT_CLOCK_WR_0 BT_CLOCK_WR[7:0] BT_CLOCK_WR_1 BT_CLOCK_WR[15:8] BT_CLOCK_WR_2 BT_CLOCK_WR[23:16] BT_CLOCK_WR_3 WHITENING SINGLE_FREQUENCY_SEL[6:0] LN_BT_CLOCK[7:0] M_COUNTER_2 0 PLN[2:0] LN_BT_CLOCK_0 SPI_MODE_CONFIG 1 Reserved BT_CLOCK_WR[27:24] WTPTC_1SLOT[7:0] WTPTC_1SLOT[7:0] WTPTC_1SLOT[15:8] WTPTC_1SLOT[15:8] WTPTC_3SLOT[7:0] WTPTC_3SLOT[7:0] WTPTC_3SLOT[15:8] WTPTC_3SLOT[15:8] WTPTC_5SLOT[7:0] WTPTC_5SLOT[7:0] 171 www.national.com CP3BT10 26.0 Register Bit Fields CP3BT10 Bluetooth LLC Registers 7 6 5 4 WTPTC_5SLOT[15:8] 3 2 1 0 WTPTC_5SLOT[15:8] SEQ_RESET Reserved SEQ_RESET SEQ_CONTINUE Reserved SEQ_ CONTINUE RX_STATUS Header Error Correction Reserved HEC Error CHIP_ID AM_ ADDR Error Payload CRC Error Payload Error Correction Reserved INT_VECTOR[7:0] SYSTEM_CLK_EN Reserved CLK_EN3 CLK_EN2 LINK_TIMER_WR_RD[7:0] LINKTIMER_WR_RD[7:0] LINK_TIMER_WR_RD[15:8] LINKTIMER_WR_RD[15:8] LINK_TIMER_SELECT Reserved LINK_TIMER_STATUS_ EXP_FLAG LINKLINKTIMER_ TIMER READ_ _WRITE_ VALID DONE Reserved LINKTIMER_ADJUST_PLUS[7:0] LINK_TIMER_AD_JUST _MINUS LINKTIMER_ADJUST_MINUS[7:0] 7 MCNTRL BUS_EN LINKTIMER_SELECT LINK_TIMER_AD_JUST _PLUS SLOTTIMER_WR_RD INT_SEQ_ EN LINK_TIMER_STATUS_EXP_FLAG[7:0] LINK_TIMER_STATUS_ RD_WR_FLAG FAR PACKET_ DONE CHIP_ID INT_VECTOR USB Registers Payload Length Error Reserved 6 SLOT_TIMER_WR_RD[5:0] 5 Reserved 4 3 2 1 0 HOS NAT HALT Reserved USBEN AD_EN AD[6:0] NFSR Reserved NSF[1:0] MAEV INTR RX_EV ULD NAK FRAME TX_EV ALT WARN MAMSK INTR RX_EV ULD NAK FRAME TX_EV ALT WARN ALTEV RESUME RESET SD5 SD3 EOP DMA CLKSTB Reserved ALTMSK RESUME RESET SD5 SD3 EOP DMA CLKSTB Reserved TXEV TXUDRRUN[3:0] TXFIFO[3:0] TXMSK TXUDRRUN[3:0] TXFIFO[3:0] RXEV RXOVRRUN[3:0] RXFIFO[3:0] RXMSK RXOVRRUN[3:0] RXFIFO[3:0] www.national.com 172 7 6 5 4 3 2 1 NAKEV OUT[3:0] IN[3:0] NAKMSK OUT[3:0] IN[3:0] 0 FWEV RXWARN[3:1] Reserved TXWARN[3:1] Reserved FWMSK RXWARN[3:1] Reserved TXWARN[3:1] Reserved FNH MF UL RFC Reserved FNL DMACNTRL DMAEV FN[7:0] DEN IGNRXTGL Reserved DMAMSK DTGL ADMA DMOD NTGL ARDY DSIZ DCNT DERR DSHLT DSIZ DCNT DERR DSHLT Reserved MIR EPC0 DCOUNT[7:0] AEH STALL DMAERRCNT[6:0] DEF Reserved TXD0 TXS0 Reserved ACK_STAT TX_DONE Red TCOUNT[4:0] IGN_IN RXD0 Res. SETUP TOGGLE RX_LAST Reserved STALL Reserved TX_EN Reserved ISO IGN_ SETUP EP_EN IGN_OUT RX_EN EP[3:0] TXFD[7:0] TX_URUN ACK_STAT TX_DONE TXC1 IGN_ ISOMSK EPC2 STALL TFWL[1:0] Reserved ISO TCOUNT[4:0] RFF FLUSH TOGGLE EP_EN RXD1 LAST TX_EN EP[3:0] RXFD[7:0] RXS1 RX_ERR RXC1 Reserved EPC3 STALL SETUP TOGGLE RFWL[1:0] Reserved ISO RX_LAST Res. RCOUNT[4:0] FLUSH EP_EN TXD2 TXS2 TOGGLE RCOUNT[3:0] FLUSH TXD1 TXS1 FLUSH RXFD[7:0] RXC0 EPC1 EP[3:0] TXFD[7:0] TXC0 RXS0 DSRC[2:0] STAT[7:0] DMACNT DMAERR FN[10:8] IGN_ SETUP Reserved RX_EN EP[3:0] TXFD[7:0] TX_URUN ACK_STAT TX_DONE TXC2 IGN_ ISOMSK EPC4 STALL TFWL[1:0] Reserved ISO TCOUNT[4:0] RFF FLUSH EP_EN RXD2 TOGGLE LAST TX_EN EP[3:0] RXFD[7:0] 173 www.national.com CP3BT10 USB Registers CP3BT10 USB Registers 7 6 5 4 RXS2 RX_ERR SETUP TOGGLE RX_LAST RXC2 Reserved EPC5 STALL RFWL[1:0] Reserved 3 IGN_ SETUP FLUSH EP_EN TXD3 TXS3 1 0 RCOUNT[4:0] Reserved ISO 2 Reserved RX_EN EP[3:0] TXFD[7:0] TX_URUN ACK_STAT TX_DONE TXC3 IGN_ ISOMSK EPC6 STALL TCOUNT[4:0] TFWL[1:0] Reserved RFF ISO FLUSH TOGGLE EP_EN RXD3 LAST TX_EN EP[3:0] RXFD[7:0] RXS3 RX_ERR RXC3 Reserved DMAC 20..16 15 Registers SETUP TOGGLE RX_LAST RFWL[1:0] 14 13 12 RCOUNT[4:0] Reserved 11 10 IGN_ SETUP FLUSH 9 8 7 6 ADCA Device A Address Counter ADRA Device A Address ADCB Device B Address Counter ADRB Device B Address BLTC N/A Block Length Counter BLTR N/A Block Length DMACNTL N/A Res. INCB DMASTAT System Configuration Registers MCFG ADB www.national.com SW Res. RQ ADA OT N/A 7 Reserved 6 5 MEM_IO_ MISC_IO_ SPEED SPEED DBGCFG MSTAT INCA 5 Reserved 4 DIR IND TCS Reserved VLD 4 3 USB_ ENABLE SCLKOE 2 DPGM BUSY 174 PGMBUSY 2 1 0 EO VR ETC CH EN CH OVR AC TC 1 MCLKOE PLLCLKOE Reserved Reserved 3 RX_EN OENV2 0 EXIOE FREEZE ON OENV1 OENV0 15 12 11 10 9 8 BCFG 7 6 5 4 3 2 1 Reserved IOCFG Reserved EWR IPST Res. BW Reserved HOLD WAIT SZCFG0 Reserved FRE IPRE IPST Res. BW WBR RBE HOLD WAIT SZCFG1 Reserved FRE IPRE IPST Res. BW WBR RBE HOLD WAIT SZCFG2 Reserved FRE IPRE IPST Res. BW WBR RBE HOLD WAIT TBI Register 7 6 TMODE Flash Program Memory Interface Registers FMIBAR 5 4 Reserved 15 14 13 12 11 3 TSTEN 10 9 8 2 1 ENMEM 7 6 5 Reserved 0 TMSEL 4 3 2 1 0 IBA FMIBDR IBD FM0WER FM0WE[15:0] FM1WER FM1WE[15:0] FM2WER FM2WE[15:0] FM3WER FM3WE[15:0] FMCTRL 0 Reserved MER PER PE IENP DIS LOW Res. CWD ROG VRF PRW FMSTAT Reserved FM DE FM PERR EERR RR FULL BUSY FMPSR Reserved FTDIV[4:0] FMSTART Reserved FTSTART[7:0] FMTRAN Reserved FTTRAN[7:0] FMPROG Reserved FTPROG[7:0] FMPERASE Reserved FTPER[7:0] FMMERASE0 Reserved FTMER[7:0] FMEND Reserved FTEND[7:0] FMMEND Reserved FTMEND[7:0] FMRCV Reserved FTRCV[7:0] 175 www.national.com CP3BT10 BIU Registers CP3BT10 Flash Program Memory Interface Registers 15 14 13 12 11 10 9 FMAR0 FMAR1 8 6 5 4 3 2 RDPROT WRPROT Res. ISPE EMPTY 15 14 13 12 11 10 9 8 7 BOOTAREA 6 5 4 Reserved IBD FSM0WER FM0WE[15:0] FSM1WER FM1WE[15:0] FSM2WER FM2WE[15:0] FSM3WER FM3WE[15:0] FSMCTRL Reserved FSMSTAT 3 2 1 MER PER PE IENP DIS LOW Res. CWD ROG VRF PRW DE FM FM PE RR FULL BUSY RR Reserved FSMPSR Reserved Reserved FTSTART[7:0] FSMTRAN Reserved FTTRAN[7:0] FSMPROG Reserved FTPROG[7:0] FSMPERASE Reserved FTPER[7:0] FSMMERASE0 Reserved FTMER[7:0] FSMEND Reserved FTEND[7:0] FSMMEND Reserved FTMEND[7:0] FSMRCV Reserved FTRCV[7:0] FSMAR0 EE RR FTDIV[3:0] FSMSTART Res. Reserved WRPROT 0 IBA FSMIBDR RDPROT ISPE FSMAR2 www.national.com 0 CADR15:0 FSMIBAR FSMAR1 1 Reserved FMAR2 Flash Data Memory Interface Registers 7 CADR15:0 176 EMPTY BOOTAREA 15 14 13 12 11 10 9 8 CVSDIN 7 6 5 4 3 2 CVSDOUT PCMIN PCMIN PCMOUT PCMOUT LOGIN Reserved LOGIN LOGOUT Reserved LOGOUT LINEARIN LINEARIN LINEAROUT LINEAROUT PCM CO NV Reserved CVSTAT CVSD CONV Reserved CVS DMA DMA DMA DMA CVS PCM CLK DER PI PO CI CO DINT INT EN RINT CV EN PCM CVN INT F CV NE CVOUTST CVTEST CVINST Reserved CVDECOUT[15:0] CVENCIN CVENCIN[15:0] CVENCPR CVENCPRT[15:0] 7 6 Reserved Reserved 5 4 3 2 1 0 POR ACE2 ACE1 PLLPWD FCLK SCLK MODE FCDIV PRSSC SCDIV PRSAC PMM Register PMMCR PMMSR TB CVRDAT[15:0] CVDECOUT PRSFC RT CVRADD[6:0] CVRDAT CRCTRL CVF CVE TEST ENC DEC _VAL _IN _EN Reserved CVRADD CLK3RES Registers 0 CVSDIN CVSDOUT CVCTRL 1 ACDIV2 ACDIV1 7 6 5 4 3 2 1 0 HCCH HCCM DHC DMC WBPSM HALT IDLE PSM OHC OMC OLC Reserved 177 www.national.com CP3BT10 CVSD/PCM Registers CP3BT10 MIWU16 Registers 15 14 13 12 11 10 9 8 7 WKEDG WKED WKENA WKEN WKINTR6 WKINTR5 WKINTR4 6 WKINTR3 5 4 3 2 1 0 WKICTL1 WKINTR7 WKINTR2 WKINTR1 WKINTR0 WKICTL2 WKINTR15 WKINTR14 WKINTR13 WKINTR12 WKINTR11 WKINTR10 WKINTR9 WKINTR8 WKPND WKPD WKPCL WKCL WKIENA WKIEN GPIO Registers 7 6 5 4 3 2 1 PxALT Px Pins Alternate Function Enable PxDIR Px Port Direction PxDIN Px Port Output Data PxDOUT Px Port Input Data PxWPU Px Port Weak Pull-Up Enable PxHDRV Px Port High Drive Strength Enable PxALTS Px Pins Alternate Function Source Selection AAI Registers 15 14 13 12 11 10 9 8 7 6 5 4 3 ARSR ARSH ARSL ATSR ATSH ATSL ARFR ARFH ARFL ARDR0 ARDH ARDL ARDR1 ARDH ARDL ARDR2 ARDH ARDL ARDR3 ARDH ARDL ATFR ATFH ARFL ATDR0 ATDH ATDL ATDR1 ATDH ATDL ATDR2 ATDH ATDL ATDR3 ATDH ATDL AGCR CLK EN www.national.com AAI IOM2 IFS EN FSL[1:0] CTF CRF IEBC FSS IEFS 178 SCS[1:0] 2 0 1 0 LPB DWL ASS 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 TX EIC TX IC RX EIC RX IC TX EIP TX IP RX EIP RX IP TX EIE TX IE RX EIE RX IE RX AF AISCR Reserved ARSCR RXFWM[3:0] RXDSA[3:0] RXSA[3:0] RXO RXE RXF ATSCR TXFWM[3:0] TXDSA[3:0] TXSA[3:0] TXU TXF TXE TXAE ACCR BCPRS[7:0] ADMACR Reserved ICU Registers FCPRS[6:0] ACO[1:0] ACD{2:0] 15 . . . 12 11 . . . 8 7 6 Reserved 0 0 IVCT TMD[3:0] 5 4 ISTAT1 IST(31:16) IENAM0 IENA(15:0) IENAM1 IENA(31:16) 6 2 1 0 INTVECT[5:0] IST(15:0) 7 RMD[3:0] 3 ISTAT0 UART Registers CSS 5 4 UTBUF UTBUF URBUF URBUF 3 2 1 0 UICTRL UEEI UERI UETI UEFCI UCTS UDCTS URBF UTBE USTAT Reserved UXMIP URB9 UBKD UERR UDOE UFE UPE UFRS Reserved UPEN UXB9 USTP URTS UFCE UCKS UBRK UMDSL1 UPSEL UERD UETD UBAUD UPSC[4:0] UOVR UOVSR[3:0] Reserved USPOS USMD Reserved 15 . . . 9 8 USAMP[3:0] 7 6 MWDAT MWSTAT UMOD UDIV[10:8] Reserved UMDSL2 MWCTL1 UATN UDIV[7:0] UPSR MWSPI16 Registers UCHAR 5 4 3 2 1 0 EIO ECHO MOD MNS MWEN OVR RBF BSY MWDAT SCDV SCIDL SCM EIW Reserved 179 EIR www.national.com CP3BT10 AAI Registers CP3BT10 ACB Registers 7 6 5 4 ACBSDA 2 1 0 DATA ACBST ACBCST 3 SLVSTP SDAST BER NEGACK STASTR NMATCH MASTER XMIT TGSCL TSDA GMATCH MATCH BB BUSY GCMEN ACK Reserved INTEN STOP START ARPMATCH MATCHAF ACBCTL1 STASTRE ACBADDR SAEN NMINTE ADDR ACBCTL2 SCLFRQ[6:0] ACBADDR2 ENABLE SAEN ADDR ACBCTL3 Reserved TWM Registers 15 . . . 8 7 TWCFG Reserved TWCP Reserved ARPEN 6 5 Reserved 4 3 2 1 0 WDSDME WDCT0I LWDCNT LTWMT0 LTWCP LTWCFG Reserved TWMT0 MDIV PRESET T0CSR Reserved WDCNT Reserved PRESET WDSDM Reserved RSTDATA MFT16 Registers SCLFRQ[8:7] 15 . . . 8 Reserved 7 FRZT0E WDTLD 6 5 4 TCNT1 TCNT1 TCRA TCRA TCRB TCRB TCNT2 TCNT2 3 2 TC RST 1 0 TPRSC Reserved TCKC Reserved TCTRL Reserved TEN TAOUT TBEN TAEN TBEDG TAEDG TICTL Reserved TDIEN TCIEN TBIEN TAIEN TDPND TCPND TBPND TAPND TICLR Reserved TDCLR TCCLR TBCLR TACLR www.national.com Reserved T0INTE CLKPS Reserved C2CSEL Reserved 180 C1CSEL TMDSEL MODE 15 14 TMOD4 13 12 T8 T7 RUN RUN 11 10 TMOD3 9 8 T6 T5 RUN RUN 7 6 TMOD2 5 4 T4 T3 RUN RUN 3 2 TMOD1 1 0 T2 T1 RUN RUN IO1CTL P4 POL C4EDG P3 POL C3EDG P2 POL C2EDG P1 POL C1EDG IO2CTL P7 POL C7EDG P6 POL C6EDG P5 POL C5EDG P5 POL C5EDG INTCTL I4DEN I4CEN I4BEN I4AEN I3DEN I3CEN I3BEN I3AEN I2DEN I2CEN I2BEN I2AEN I1DEN I1CEN I1BEN I1AEN INTPND I4DPD I4CPD I4BPD I4APD I3DPD I3CPD I3BPD I3APD I2DPD I2CPD I2BPD I2APD I1DPD I1CPD I1BPD I1APD CLK1PS C2PRSC C1PRSC COUNT1 CNT1 PERCAP1 PCAP1 DTYCAP1 DCAP1 COUNT2 CNT2 PERCAP2 PCAP2 DTYCAP2 DCAP2 CLK2PS C4PRSC C3PRSC COUNT3 CNT3 PERCAP3 PCAP3 DTYCAP3 DCAP3 COUNT4 CNT4 PERCAP4 PCAP4 DTYCAP4 DCAP4 181 www.national.com CP3BT10 VTU Registers CP3BT10 27.0 Electrical Characteristics 27.1 ABSOLUTE MAXIMUM RATINGS If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/Distributors for availability and specifications. Supply voltage (VCC) All input and output voltages with respect to GND* 3.6V -0.5V to IOVCC + 0.5V ESD protection level 2 kV (Human Body Model) Allowable sink/source current per signal pin 27.2 Total current into IOVCC pins Total current into VCC pins (source) Total current out of GND pins (sink) Latch-up immunity Storage temperature range 200 mA 200 mA 200 mA ±200 mA -65°C to +150°C Note: Absolute maximum ratings indicate limits beyond which damage to the device may occur. DC and AC electrical specifications are not ensured when operating the device at absolute maximum ratings. *The latch-up tolerance on ACCESS.bus pins exceeds 150 mA. ±10 mA DC ELECTRICAL CHARACTERISTICS (Temperature: -40°C ≤ TA ≤ +85°C) Symbol Parameter Conditions Min Max Units Vcc Digital Logic Supply Voltage 2.25 2.75 V IOVcc I/O Supply Voltage 2.25 3.63 V AVcc Analog PLL Supply Voltage 2.25 2.75 V UVcc USB Transceiver Power Supply 2.97 3.63 V 0.3 Vcc V a VIL Logical 0 Input Voltage (except X2CKI) -0.5 VIH Logical 1 Input Voltage (except X2CKI) 0.7 IOVcc IOVcc + 0.5 a V Vxl1 X1CKI Low Level Input Voltage External X1 clock -0.5 a 0.3 Vcc V Vxh1 X1CKI High Level Input Voltage OSC External X1 clock 0.7 Vcc Vcc + 0.5 V 0.6 V Vcc + 0.5 V a Vxl2 X2CKI Logical 0 Input Voltage External X2 clock -0.5 Vxh2 X2CKI Logical 1 Input Voltage External X2 clock 0.7 Vcc a Vhys Hysteresis Loop Width IOH Logical 1 Output Current IOL 0.1 IOVcc V VOH = 1.8V, IOVcc = 2.25V -1.6 mA Logical 0 Output Current VOL = 0.45V, IOVcc = 2.25V 1.6 mA IOLACB SDA, SCL Logical 0 Output Current VOL = 0.4V, IOVcc = 2.25V 3.0 mA IOHW Weak Pull-up Current VOH = 1.8V, IOVcc =2.25V -10 µA IIL RESET pin Weak Pull-down Current VIL = 0.45V, IOVcc = 2.25V 0.4 µA IL High Impedance Input Leakage Current 0V ≤ Vin ≤ IOVcc -2.0 2.0 µA IO(Off) Output Leakage Current (I/O pins in input mode) 0V ≤ Vout ≤ Vcc -2.0 2.0 µA Icca1 Digital Supply Current Active Mode b Vcc = 2.75V, IOVcc = 3.63V 12 mA Icca2 Digital Supply Current Active Mode c Vcc = 2.75V, IOVcc = 3.63V 8 mA www.national.com 182 Parameter Conditions Min Max Units Iccprog Digital Supply Current Active Mode d Vcc = 2.75V, IOVcc = 3.63V 15 mA Iccps Digital Supply Current Power Save Mode e Vcc = 2.75V, IOVcc = 3.63V 4.0 mA Iccid Digital Supply Current Idle Mode f Vcc = 2.75V, IOVcc = 3.63V 950 µA Iccq Digital Supply Current Halt Mode f,g,h Vcc = 2.75V, IOVcc = 3.63V 700 µA a. Guaranteed by design b. Test code executing from internal RAM. No peripheral blocks other than PLL and Auxiliary Clock enabled. X1CLKI is 24 MHz. Not programming Flash memory. Typical applications will show 16 mA (Icca1 + 4 mA) at 24 MHz executing code from flash memory. c. Waiting for interrupt on executing WAIT instruction, Iout = 0 mA, X1CKI = 12 MHz, PLL enabled (4×), internal system clock is 24 MHz, not programming Flash memory d. Same conditions as Icca1, but programming or erasing Flash memory page e. Running from internal memory (RAM), Iout = 0 mA, XCKI1 = 12 MHz, PLL disabled, X2CKI = 32.768 kHz, device put in power-save mode, Slow Clock derived from XCKI1 f. Iout = 0 mA, XCKI1 = off, X2CKI = 32.768 kHz g. USB switched off (suspend) h. Halt current approximately doubles for every 20°C. 27.3 Symbol USB TRANSCEIVER ELECTRICAL CHARACTERISTICS (Temperature: -40°C ≤ TA ≤ +85°C) Parameter Conditions Max Units VDI Differential Input Sensitivity -0.2 0.2 V VCM Differential Common Mode Range 0.8 2.5 V VSE Single-Ended Receiver Threshold 0.8 2.0 V VOL Output Low Voltage VOH Output High Voltage VOZ TRI-STATE Data Line Leakage CTRN Transceiver Capacitance (D+) - (D-) Min RL = 1.5K ohm to 3.6V 0.3 2.8 0V < VIN < 3.3V 183 -10 V V 10 µA 20 pF www.national.com CP3BT10 Symbol CP3BT10 27.4 FLASH MEMORY ON-CHIP PROGRAMMING Symbol Parameter Conditions tSTART Program/Erase to NVSTR Setup Time (NVSTR = Non-Volatile Storage tTRAN NVSTR to Program Setup Timeb tPROG tPERASE tMERASE tEND tMEND Max 5 - µs 10 - µs 20 40 µs 20 - ms 200 - ms 5 - µs 100 - µs 1 - µs 128K program blocks - 8 ms 8K data block - 4 ms 20,000 - cycles 100 - years c Programming Pulse Width d Page Erase Pulse Width Module Erase Pulse Width NVSTR Hold Time e f NVSTR Hold Time (Module Erase) g h tRCV Recovery Time tHV Cumulative Program High Voltage Period For Each Row After Erasei tHV Min Write/Erase Endurance Data Retention Units a 25°C a. Program/erase to NVSTR Setup Time is determined by the following equation: tSTART = Tclk × (FTDIV + 1) × (FTSTART + 1), where Tclk is the System Clock period, FTDIV is the contents of the FMPSR or FSMPSR register, and FTSTART is the contents of the FMSTART or FSMSTART register b. NVSTR to Program Setup Time is determined by the following equation: tTRAN = Tclk × (FTDIV + 1) × (FTTRAN + 1), where Tclk is the System Clock period, FTDIV is the contents of the FMPSR or FSMPSR register, and FTTRAN is the contents of the FMTRAN or FSMTRAN register c. Programming Pulse Width is determined by the following equation: tPROG = Tclk × (FTDIV + 1) × 8 × (FTPROG + 1), where Tclk is the System Clock period, FTDIV is the contents of the FMPSR or FSMPSR register, and FTPROG is the contents of the FMPROG or FSMPROG register d. Page Erase Pulse Width is determined by the following equation: tPERASE = Tclk × (FTDIV + 1) × 4096 × (FTPER + 1), where Tclk is the System Clock period, FTDIV is the contents of the FMPSR or FSMPSR register, and FTPER is the contents of the FMPERASE or FSMPERASE register e. Module Erase Pulse Width is determined by the following equation: tMERASE = Tclk × (FTDIV + 1) × 4096 × (FTMER + 1), where Tclk is the System Clock period, FTDIV is the contents of the FMPSR or FSMPSR register, and FTMER is the contents of the FMMERASE0 or FSMMERASE0 register f. NVSTR Hold Time is determined by the following equation: tEND = Tclk × (FTDIV + 1) × (FTEND + 1), where Tclk is the System Clock period, FTDIV is the contents of the FMPSR or FSMPSR register, and FTEND is the contents of the FMEND or FSMEND register g. NVSTR Hold Time (Module Erase) is determined by the following equation: tMEND = Tclk × (FTDIV + 1) × 8 × (FTMEND + 1), where Tclk is the System Clock period, FTDIV is the contents of the FMPSR or FSMPSR register, and FTMEND is the contents of the FMMEND or FSMMEND register h. Recovery Time is determined by the following equation: tRCV = Tclk × (FTDIV + 1) × (FTRCV + 1), where Tclk is the System Clock period, FTDIV is the contents of the FMPSR or FSMPSR register, and FTRCV is the contents of the FMRCV or FSMRCV register i. Cumulative program high voltage period for each row after erase tHV is the accumulated duration a flash cell is exposed to the programming voltage after the last erase cycle. www.national.com 184 OUTPUT SIGNAL LEVELS The RESET and NMI input pins are active during the Power Save mode. In order to guarantee that the Power Save curAll output signals are powered by the digital supply (VCC). rent not exceed 1 mA, these inputs must be driven to a voltTable 57 summarizes the states of the output signals during age lower than 0.5V or higher than VCC - 0.5V. An input the reset state (when VCC power exists in the reset state) voltage between 0.5V and (VCC - 0.5V) may result in power and during the Power Save mode. consumption exceeding 1 mA. Table 57 Output Pins During Reset and Power-Save Reset State (with Vcc) Signals on a Pin Power Save Mode PB7:0 TRI-STATE Previous state PC7:0 TRI-STATE Previous state PG5, PG3:0 TRI-STATE Previous state PH7:0 TRI-STATE Previous state PI7:0 TRI-STATE Previous state 27.6 Comments I/O ports will maintain their values when entering power-save mode CLOCK AND RESET TIMING Table 58 Clock and Reset Signals Symbol Figure Description Reference Min (ns) Max (ns) 83.33 83.33 Clock Input Signals tX1p 72 X1 period Rising Edge (RE) on X1 to next RE on X1 tX1h 72 X1 high time, external clock At 2V level (Both Edges) (0.5 Tclk) - 5 tX1l 72 X1 low time, external clock At 0.8V level (Both Edges) (0.5 Tclk) - 5 a tX2p 72 X2 period tX2h 72 X2 high time, external clock RE on X2 to next RE on X2 At 2V level (both edges) (0.5 Tclk) - 500 10,000 tX2l 72 X2 low time, external clock At 0.8V level (both edges) (0.5 Tclk) - 500 tIH 73 Input hold time (NMI, RXD1, RXD2) After RE on CLK 0 Reset and NMI Input Signals tIW 73 NMI Pulse Width NMI Falling Edge (FE) to RE 20 tRST 74 RESET Pulse Width RESET FE to RE 100 tR 74 Vcc Rise Time 0.1 Vcc to 0.9 Vcc a. Only when operating with an external square wave on X2CKI; otherwise a 32 kHz crystal network must be used between X2CKI and X2CKO. If Slow Clock is internally generated from Main Clock, it may not exceed this given limit. 185 www.national.com CP3BT10 27.5 CP3BT10 tX1p X1CKI tX1h tX1l tX2p X2CKI tX2h tX2l DS095 Figure 72. Clock Timing CLK tlS tlH tIW NMI DS096 Figure 73. NMI Signal Timing CLK tRST RESET DS097 Figure 74. Non-Power-On Reset 0.9 VCC VCC 0.1 VCC tR Figure 75. www.national.com DS115 Power-On Reset 186 CP3BT10 27.7 I/O PORT TIMING Table 59 I/O Port Signals Symbol Figure Description Reference Min (ns) Max (ns) I/O Port Input Signals tIS 76 Input Setup Time Before Falling Edge (FE) on System Clock 22.5 - tIH 76 Input Hold Time After FE on System Clock 0 - - 3 I/O Port Output Signals tCOv1 76 Output Valid Time After FE on System Clock CLK tIS Port Input tlH Port Output tCOv1 tCOv1 DS100 Figure 76. I/O Port Timing 187 www.national.com CP3BT10 27.8 ADVANCED AUDIO INTERFACE (AAI) TIMING Table 60 Advanced Audio Interface (AAI) Signals Symbol Figure Description Reference Min (ns) Max (ns) AAI Input Signals tRDS 77,79 Receive Data Setup Time Before Falling Edge (FE) on SRCLK 20 - tRDH 77,79 Receive Data Hold Time After FE on SRCLK 20 - tFSS 77 Frame Sync Setup Time Before Rising Edge (RE) on SRCLK 20 - tFSH 77 Frame Sync Hold Time After RE on SRCLK 20 - AAI Output Signals tCP 77 Receive/Transmit Clock Period RE on SRCLK/SCK to RE on SRCLK/SCK 976.6 - tCL 77 Receive/Transmit Low Time FE on SRCLK/SCK to RE on SRCLK/SCK 488.3 - tCH 77 Receive/Transmit High Time RE on SRCLK/SCK to FE on SRCLK/SCK 488.3 - tFSVH 77,79 Frame Sync Valid High RE on SRCLK/SCK to RE on SRFS/SFS - 20 tFSVL 77,79 Frame Sync Valid Low RE on SRCLK/SCK to FE on SRFS/SFS - 20 tTDV 78,80 Transmit Data Valid RE on SCK to STD Valid - 20 tCP SRCLK 0 1 tCH 2 tCL SRFS tFSVH tFSVL SRD 0 1 tRDH tRDS DS116 Figure 77. Receive Timing, Short Frame Sync www.national.com 188 0 1 CP3BT10 SCK 2 SFS STD 0 1 tTDV DS117 Figure 78. SRCLK 0 Transmit Timing, Short Frame Sync 1 2 N SRFS tFSVL tFSVH SRD 0 1 tRDH tRDS DS118 Figure 79. Receive Timing, Long Frame Sync SCK 0 1 2 N SFS STD 0 1 tTDV DS119 Figure 80. Transmit Timing, Long Frame Sync 189 www.national.com CP3BT10 27.9 MICROWIRE/SPI TIMING Table 61 Microwire/SPI Signals Symbol Figure Description Reference Min (ns) Max (ns) Microwire/SPI Input Signals tMSKh 81 Microwire Clock High At 2.0V (both edges) 80 - tMSKl 81 Microwire Clock Low At 0.8V (both edges) 80 - SCIDL bit = 0; Rising Edge (RE) MSK to next RE MSK 81 tMSKp Microwire Clock Period SCIDL bit = 1; Falling Edge (FE) MSK to next FE MSK 82 200 - tMSKh 81 MSK Hold (slave only) After MWCS goes inactive 40 - tMSKs 81 MSK Setup (slave only) Before MWCS goes active 80 - SCIDL bit = 0; After FE MSK 81 MWCS Hold (slave only) tMCSh 82 SCIDL bit = 1; After RE MSK 81 SCIDL bit = 0; Before RE MSK tMCSs MWCS Setup (slave only) 82 SCIDL bit = 1; Before FE MSK 81 Normal Mode; After RE MSK Microwire Data In Hold (master) 83 Alternate Mode; After FE MSK 81 Normal Mode; After RE MSK tMDIh Microwire Data In Hold (slave) 83 Alternate Mode; After FE MSK 81 Normal Mode; Before RE MSK Microwire Data In Setup tMDIs Alternate Mode; Before FE MSK 83 40 80 0 40 80 - Microwire/SPI Output Signals tMSKh 81 Microwire Clock High At 2.0V (both edges) 40 - tMSKl 81 Microwire Clock Low At 0.8V (both edges) 40 - 81 tMSKp Microwire Clock Period 82 SCIDL bit = 0: Rising Edge (RE) MSK to next RE MSK SCIDL bit = 1: Falling Edge (FE) MSK to next FE MSK tMSKd 81 MSK Leading Edge Delayed (master only) Data Out Bit #7 Valid tMDOf 81 Microwire Data Float b (slave only) After RE on MCSn 81 tMDOh Microwire Data Out Hold 82 tMDOnf 85 www.national.com Microwire Data No Float (slave only) Normal Mode; After FE MSK Alternate Mode; After RE MSK After FE on MWCS 190 100 0.5 tMSK 1.5 tMSK - 25 - 0.0 0 25 Symbol Figure tMDOv tMITOp Description 81 Microwire Data Out Valid 85 MDODI to MDIDO (slave only) Reference Normal Mode; After FE on MSK Alternate Mode; After RE on MSK Propagation Time Value is the same in all clocking modes of the Microwire Min (ns) Max (ns) - 25 - 25 tMSKp MSK tMSKh tMSKs Data In tMSKl tMSKhd msb tMDls MDIDO (slave) lsb tMDlh msb lsb tMDOf tMDOv tMDOff tMDOh MDODI (master) msb lsb tMSKd MCS (slave) tMCSs Figure 81. tMCSh DS101 Microwire Transaction Timing, Normal Mode, SCIDL = 0 191 www.national.com CP3BT10 Table 61 Microwire/SPI Signals CP3BT10 tMSKp MSK tMSKh tMSKh tMSKhd tMSKs Data In msb tMDls MDIDO (slave) lsb tMDlh msb lsb tMDOv tMDOf tMDOf tMDOh MDODO (master) msb lsb MCS (slave) tMCSs tMCSh DS102 Figure 82. www.national.com Microwire Transaction Timing, Normal Mode, SCIDL = 1 192 CP3BT10 tMSKp MSK tMSKhd tMSKs tMSKh Data In tMSKl msb tMDls MDIDO (slave) lsb tMDlh msb lsb tMDOv tMDOf tMDOf tMDOh MDODO (master) msb lsb MCS (slave) tMCSs tMCSh DS103 Figure 83. Microwire Transaction Timing, Alternate Mode, SCIDL = 0 193 www.national.com CP3BT10 tMSKp MSK tMSKhd tMSKs tMSKh Data In tMSKh msb lsb tMDlh tMDls MDIDO (slave) msb lsb tMDOf tMDOv tMDOff tMDOh MDODI (master) msb lsb tSKd MCS (slave only) tMCSs tMCSh DS104 Figure 84. Microwire Transaction Timing, Alternate Mode, SCIDL = 1 tMSKp MSK tMSKhd tMSKs tMSKh MDODI (slave) tMSKl Dl msb tMDls Dl lsb tMDlh tMITOp MDIDO (slave) tMITOp DO msb DO lsb tMDOnf tMDOf MCS tMCSs tMCSh Figure 85. Microwire Transaction Timing, Data Echoed to Output, Normal Mode, SCIDL = 0, ECHO = 1, Slave Mode www.national.com 194 DS105 CP3BT10 27.10 ACCESS.BUS TIMING Table 62 ACCESS.bus Signals Symbol Figure Description Reference Min (ns) Max (ns) tSCLhigho - ACCESS.bus Input Signals tBUFi 87 Bus free time between Stop and Start Condition tCSTOsi 87 SCL setup time Before Stop Condition tCSTRhi 87 SCL hold time After Start Condition (8 × tCLK) - tSCLri (8 × tCLK) - tSCLri tCSTRsi 87 SCL setup time Before Start Condition (8 × tCLK) - tSCLri - 2 × tCLK - - tDHCsi 88 Data High setup time Before SCL Rising Edge (RE) tDLCsi 87 Data Low setup time Before SCL RE 2 × tCLK - tSCLfi 86 SCL signal Rise time - 300 tSCLri 86 SCL signal Fall time - 1000 tSCLlowi 89 SCL low time After SCL Falling Edge (FE) 16 × tCLK - tSCLhighi 89 SCL high time After SCL RE - tSDAfl 86 SDA signal Fall time 16 × tCLK - 300 tSDAri 86 SDA signal Rise time tSDAhi 89 SDA hold time After SCL FE tSDAsi 89 SDA setup time Before SCL RE - 1000 0 - 2 × tCLK - ACCESS.bus Output Signals tBUFo 87 Bus free time between Stop and Start Condition tCSTOso 87 SCL setup time tCSTRho 87 SCL hold time tCSTRso 88 SCL setup time tDHCso 88 Data High setup time tDLCso 87 Data Low setup time tSCLfo 86 tSCLro 86 tSCLlowo 89 tSCLhigho - tSCLhigho - After Start Condition tSCLhigho - Before Start Condition tSCLhigho - Before SCL R.E. tSCLhigho -tSDAro - Before SCL R.E. tSCLhigho -tSDAfo - SCL signal Fall time - 300 c SCL signal Rise time - SCL low time Before Stop Condition After SCL F.E. -d (K × tCLK) -1e (K × tCLK) -1e - 89 SCL high time tSDAfo 86 SDA signal Fall time - 300 tSDAro 86 SDA signal Rise time - - tSDAho 89 SDA hold time After SCL F.E. (7 × tCLK) - tSCLfo - tSDAvo 89 SDA valid time After SCL F.E. - (7 × tCLK) + tRD tSCLhigh After SCL R.E. - o 195 www.national.com CP3BT10 0.7VCC 0.7VCC 0.3VCC 0.3VCC SDA tSDAr tSDAf 0.7VCC 0.7VCC 0.3VCC 0.3VCC SCL tSCLr tSCLf Note: In the timing tables the parameter name is added with an "o" for output signal timing and "i" for input signal timing. DS106 Figure 86. ACB Signals (SDA and SCL) Timing Stop Condition Start Condition SDA tDLCs SCL tCSTOs tBUF tCSTRh Note: In the timing tables the parameter name is added with an "o" for output signal timing and "i" for input signal timing. Figure 87. ACB Start and Stop Condition Timing Start Condition SDA SCL tCSTRh tCSTRs tDHCs Note: In the timing tables the parameter name is added with an "o" for output signal timing and "i" for input signal timing. DS108 Figure 88. www.national.com ACB Start Condition Timing 196 DS107 CP3BT10 SDA tSDAsi SCL tSCAvo tSDAh tCSLlow tSCLhigh Note: In the timing tables the parameter name is added with an "o" for output signal timing and "i" for input signal timing. unless the parameter already includes the suffix. DS109 Figure 89. ACB Data Timing 197 www.national.com CP3BT10 27.11 USB PORT AC CHARACTERISTICS Table 63 USB Port Signals Symbol Conditionsa Description Min Typ Max Units TR Rise Time CL = 50 pF 4 20 ns TF Fall Time CL = 50 pF 4 20 ns TRFM Fall/Rise Time Matching (TR/TF) CL = 50 pF 90 110 % VCRS Output Signal Crossover Voltage CL = 50 pF 1.3 2.0 V ZDRV Driver Output Impedance CL = 50 pF 28 43 ohms a. Waveforms measured at 10% to 90%. 27.12 MULTI-FUNCTION TIMER (MFT) TIMING Table 64 Multi-Function Timer Input Signals Symbol Figur e tTAH 90 TA High Time Rising Edge (RE) on CLK TCLK + 5 tTAL 90 TA Low Time RE on CLK TCLK + 5 Description Reference Min (ns) CLK tTAL /tTBH tTAL /tTBL TA/TB DS169 Figure 90. www.national.com Multi-Function Timer Input Timing 198 Max (ns) CP3BT10 27.13 VERSATILE TIMING UNIT (VTU) TIMING Table 65 Versatile Timing Unit Input Signals Symbol Figur e tTIOH 90 TIOx Input High Time Rising Edge (RE) on CLK tTIOL 90 TIOx Input Low Time RE on CLK Description Reference Min (ns) Max (ns) 1.5 × TCLK + 5ns 1.5 × TCLK + 5ns CLK tTIOL tTIOH TIOx DS110 Figure 91. Versatile Timing Unit Input Timing 199 www.national.com CP3BT10 27.14 EXTERNAL BUS TIMING Table 66 Symbol Figure External Bus Signals Description Reference Min (ns) Max (ns) External Bus Input Signals t1 92, Input Setup Time 94, D[15:0] 95, 96 Before Rising Edge (RE) on CLK 8 - t2 92, Output Hold Time 94, D[15:0] 95, 96 After RE on CLK 0 - After RE on CLK - 8 External Bus Output Signals Output Valid Time D[15:0] t3 92, 93 t4 92, Output Valid Time 93, A[21:0] (CP3BT10) 94, A[22:0] (CP3BT13) 95, 96 After RE on CLK - 8 t5 92, 93, 94, 95, 96 Output Active/Inactive Time RD SEL[1:0] SELIO After RE on CLK - 8 t6 92, 93 Output Active/Inactive Time WR[1:0] After RE on CLK - 0.5 Tclk + 8 t7 94 Minimum Inactive Time RD At 2.0V Tclk - 4 - t8 92 Output Float Time D[15:0] After RE on CLK - 8 t9 92 Minimum Delay Time From RD Trailing Edge (TE) to D[15:0] driven Tclk - 4 - From RD TE to SELn Leading Edge (LE) 0 - From SELx TE to SELy LE 0 - After RE on CLK 0 - After RE on CLK 0.5 Tclk - 3 - t10 t11 92, 93 Minimum Delay Time 93 Minimum Delay Time t12 Output Hold Time A22 (CP3BT13 only) 92, A[21:0] 93, D[15:0] 94, RD 95, 96 SEL[2:0] SELIO t13 92, 93 www.national.com Output Hold Time WR[1:0] 200 Bus State T1 Early Write T2 T1 T2 CP3BT10 Normal Read Normal Read T3 T1 T2 CLK t4 t4, t12 t5, t12 t5, t12 A[21:0] A22 ('13 only) SELx t5, t12 t5, t12 SELy (y ≠ x) t2 t3 D[15:0] In t1 t8, t12 Out In t5, t12 RD t5, t12 t9 t6, t13 t6, t13 WR[1:0] DS124 Figure 92. Early Write Between Normal Read Cycles (No Wait States) 201 www.national.com CP3BT10 Normal Read Bus State T1 Late Write T2 T1 Normal Read T2 T1 T2 CLK t4, t12 t4, t12 A[21:0] A22 ('13 only) t5, t12 t5, t12 SELx (y ≠ x) t11 SELy (y ≠ x) t5, t12 t5, t12 t3 D[15:0] t8, t12 In Out In t10 RD t9 t5, t12 t5, t12 t6, t13 WR[1:0] t6, t13 DS125 Figure 93. Late Write Between Normal Read Cycles (No Wait States) www.national.com 202 T1 Bus State CP3BT10 Normal Read Normal Read T2 T2B T1 T2 T2B CLK t4, t12 t4, t12 t4 A[21:0] A22 ('13 only) t5, t12 t5, t12 SELx (y ≠ x) t5, t12 SELy (y ≠ x) t5, t12 t2 t2 t1 D[15:0] t1 In In In In t5, t12 RD t5, t12 t7 WR[1:0] DS126 Figure 94. Consecutive Normal Read Cycles (Burst, No Wait States) 203 www.national.com CP3BT10 T1 Bus State TW T2 TH CLK t4, t12 t4 A21:0 A22 ('13 only) t5, t12 t5, t12 SELn, SELIO t2 t1 D[15:0] t5, t12 t5, t12 RD WR[1:0] DS127 Figure 95. Normal Read Cycle (Wait Cycle Followed by Hold Cycle) www.national.com 204 Bus State Tidle Early Write T1-2 T1 T2 CP3BT10 Fast Read Fast Read T3 T1-2 T1 CLK t4, t12 t4 A[21:0] A22 ('13 only) SELx (y ≠ x) t5, t12 t5, t12 SELy (y ≠ x) t1 t2 D[15:0] In Out In RD t5, t12 t5, t12 WR[1:0] DS128 Figure 96. Early Write Between Fast Read Cycles 205 www.national.com PG2/RTS/WUI12 PG3/CTS/WUI13 PC1 PC2 PC3 PC4 PC5 PC6 PC7 PG5/SRFS/NMI TMS TCK TDI GND IOVCC ENV2 SEL0 SCL SDA TDO D- D+ UVCC UGND RDY SEL1 PC0 SEL2 PG1/TXD/WUI11 SELIO PG0/RXD/WUI10 A21 PI7/BTSEQ3/TA A20 PI6/BTSEQ2/WUI9 PH0/MSK/TIO1 PI5/SLE PH1/MDIDO/TIO2 PI4/SDAT PH2/MDODO/TIO3 PI3/SCLK IOVCC PH3/MWCS/TIO4 ENV0 GND IOVCC PB7 PB6 GND VCC PB5 CP3BT10 GND PB4 RESET PB3 RD PB2 WR0 PB1 WR1 PB0 A19 PI2/BTSEQ1/SRCLK A18 PI1/RFCE A17 PI0/RFSYNC A16 A0 A15 A1 PH4/SCK/TIO5 A2 A3 PH5/SFS/TIO6 RFDATA GND X1CKI/BBCLK X1CKO IOVCC AGND AVCC GND X2CKO X2CKI VCC A4 A5 A6 A7 A8 A9 ENV1 PH7/SRD/TIO8 PH6/STD/TIO7 A10 A11 A12 A13 1 A14 CP3BT10 28.0 Pin Assignments Figure 97. CP3BT10 in the 100-pin LQFP Package (Top View) www.national.com 206 DS111 PG2/RTS/WUI12 PG3/CTS/WUI13 PG5/SRFS/NMI TMS TCK TDI GND IOVCC TDO D- D+ UVCC UGND RDY CP3BT10 PH0/MSK/TIO1 PG1/TXD/WUI11 PH1/MDIDO/TIO2 PG0/RXD/WUI10 PH2/MDODI/TIO3 PI7/BTSEQ3/TA PH3/MWCS/TIO4 PI6/BTSEQ2/WUI9 ENV0 PI5/SLE CP3BT10 VCC PI4/SDAT PI3/SCLK GND PI2/BTSEQ1/SRCLK RESET PI1/RFCE PH4/SCK/TIO5 RFDATA GND X1CKI/BBCLK X1CKO IOVCC AGND AVCC GND X2CKO X2CKI VCC ENV1 PH6/STD/TIO7 Figure 98. PI0/RFSYNC 1 PH7/SRD/TIO8 PH5/SFS/TIO6 DS113 CP3BT10 in the 48-pin CSP Package (Top View) 207 www.national.com CP3BT10 29.0 Revision History Table 67 Revision History (Continued) Table 67 Revision History Date Date Major Changes From Previous Version 2/28/04 Changed NSID designations in the product selection guide. Updated Bluetooth section for LMX5251 and LMX5252 radio chips. Added BTSEQ[3:1] signals to pin descriptions, GPIO alternate functions, and package pin assignments. Changed CVSD Conversion section. Changed definition of the RESOLUTION field of the CVSD Control register (CVCTRL). Changed DC specification for Vxl2. Major Changes From Previous Version 8/5/02 Split the CP3BT10/CP3BT13 data sheet into separate data sheets for each chip. Added description of RDPROT field. 8/15/02 Clarified conditions for software DMA transfer request in Section 9.4. Removed commercial temperature range device. 9/26/02 Changed I/O Zone bus width to allow 8 bits. Removed UART synchronous mode. 3/16/04 10/8/02 Changed flash programming sequence to remove checking FMBUSY after each row. Changed LMX5251 interface circuit. Updated DC specifications Iccid and Iccq. 10/16/02 Corrections to flash memory programming sequence and MFT block diagrams. 5/20/04 Moved revision history in front of physical dimensions. Changed back page disclaimers. 11/11/02 Numerous minor corrections. Added more description to AAI section. Added external reset circuit. Fixed problems with figures. 6/23/04 Changed absolute maximum supply voltage to 3.6V. Changed processor selection guide table. 11/21/02 Converted to new data sheet format. Removed TB functionality from MFT section. 7/3/04 Changed footnote b in DC specs. Changed product selection guide table. 7/16/04 Changed product selection guide table. 8/24/04 Added AC timing specifications for GPIO. Deleted AC timing section for UART. 1/13/03 Removed erroneous warning to always write the IOCFG register with bit 1 set. Alternate clock source for Advanced Audio Interface changed to Aux1 clock. Changed warning about clock glitches to say Microwire interface must be disabled when modifying bits in MWCTL1 register. Changed bit settings which occur in step 2 of the sequence of ACCESS.bus slave mode address match or global match. Timer Mode Control Register bit 3 is reserved and bit 2 is TAEDG. Bit 7 is the TEN bit (a bit description has been added). Polarity of all of the bits in the INTCTL register has been inverted. 9/7/04 In Section 17.2, added sentence that an external frame sync must be used in asynchronous mode. In Section 12, in several places noted that Idle and Halt modes may only be entered from Active mode, and the DHC and DMC bits must be set when entering Idle and Halt modes. Added usage hints Section 17.8. Removed Section 21.4.1. 4/4/05 Added new reset circuits. Added note about fluctuations in response due to SDI activity. New back page. 5/20/03 Updated DC specifications. Fixed errors in Microwire bit and pin names. Changed UART pin names to TXD and RXD. Added Section 11.6 “Auxiliary Clocks”. Changed diagram of I/O Port Pin Logic (Section 14). 11/14/03 Defined valid range of SCDV field in Microwire/SPI module. Noted default PRSSC register value generates a Slow Clock frequency slightly higher than 32768 Hz. Clarified usage of CVSTAT register bits and fields in CVSD/PCM module. Updated layout of Bluetooth LLC registers. Added usage hint for avoiding ACCESS.bus module bus error. www.national.com 208 CP3BT10 30.0 Physical Dimensions (millimeters) unless otherwise noted Figure 99. Figure 100. 100-Pin LQFP Package 48-Pin CSP Package 209 www.national.com CP3BT10 Reprogrammable Connectivity Processor with Bluetooth and USB Interfaces National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications. For the most current product information visit us at www.national.com. LIFE SUPPORT POLICY NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT AND GENERAL COUNSEL OF NATIONAL SEMICONDUCTOR CORPORATION. As used herein: 1. Life support devices or systems are devices or systems which, (a) are intended for surgical implant into the body, or (b) support or sustain life, and whose failure to perform, when properly used in accordance with instructions for use provided in the labeling, can be reasonably expected to result in a significant injury to the user. 2. A critical component is any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system, or to affect its safety or effectiveness. BANNED SUBSTANCE COMPLIANCE National Semiconductor certifies that the products and packing materials meet the provisions of the Customer Products Stewardship Specification (CSP-9-111C2) and the Banned Substances and Materials of Interest Specification (CSP-9-111S2) and contain no “Banned Substances” as defined in CSP-9-111S2. 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