PIC18F87K90 Family Data Sheet 64/80-Pin, High-Performance Microcontrollers with LCD Driver and nanoWatt XLP Technology 2010 Microchip Technology Inc. Preliminary DS39957B Note the following details of the code protection feature on Microchip devices: • Microchip products meet the specification contained in their particular Microchip Data Sheet. • Microchip believes that its family of products is one of the most secure families of its kind on the market today, when used in the intended manner and under normal conditions. • There are dishonest and possibly illegal methods used to breach the code protection feature. All of these methods, to our knowledge, require using the Microchip products in a manner outside the operating specifications contained in Microchip’s Data Sheets. Most likely, the person doing so is engaged in theft of intellectual property. • Microchip is willing to work with the customer who is concerned about the integrity of their code. • Neither Microchip nor any other semiconductor manufacturer can guarantee the security of their code. Code protection does not mean that we are guaranteeing the product as “unbreakable.” Code protection is constantly evolving. We at Microchip are committed to continuously improving the code protection features of our products. Attempts to break Microchip’s code protection feature may be a violation of the Digital Millennium Copyright Act. If such acts allow unauthorized access to your software or other copyrighted work, you may have a right to sue for relief under that Act. Information contained in this publication regarding device applications and the like is provided only for your convenience and may be superseded by updates. It is your responsibility to ensure that your application meets with your specifications. MICROCHIP MAKES NO REPRESENTATIONS OR WARRANTIES OF ANY KIND WHETHER EXPRESS OR IMPLIED, WRITTEN OR ORAL, STATUTORY OR OTHERWISE, RELATED TO THE INFORMATION, INCLUDING BUT NOT LIMITED TO ITS CONDITION, QUALITY, PERFORMANCE, MERCHANTABILITY OR FITNESS FOR PURPOSE. Microchip disclaims all liability arising from this information and its use. Use of Microchip devices in life support and/or safety applications is entirely at the buyer’s risk, and the buyer agrees to defend, indemnify and hold harmless Microchip from any and all damages, claims, suits, or expenses resulting from such use. No licenses are conveyed, implicitly or otherwise, under any Microchip intellectual property rights. Trademarks The Microchip name and logo, the Microchip logo, dsPIC, KEELOQ, KEELOQ logo, MPLAB, PIC, PICmicro, PICSTART, PIC32 logo, rfPIC and UNI/O are registered trademarks of Microchip Technology Incorporated in the U.S.A. and other countries. FilterLab, Hampshire, HI-TECH C, Linear Active Thermistor, MXDEV, MXLAB, SEEVAL and The Embedded Control Solutions Company are registered trademarks of Microchip Technology Incorporated in the U.S.A. Analog-for-the-Digital Age, Application Maestro, CodeGuard, dsPICDEM, dsPICDEM.net, dsPICworks, dsSPEAK, ECAN, ECONOMONITOR, FanSense, HI-TIDE, In-Circuit Serial Programming, ICSP, Mindi, MiWi, MPASM, MPLAB Certified logo, MPLIB, MPLINK, mTouch, Octopus, Omniscient Code Generation, PICC, PICC-18, PICDEM, PICDEM.net, PICkit, PICtail, REAL ICE, rfLAB, Select Mode, Total Endurance, TSHARC, UniWinDriver, WiperLock and ZENA are trademarks of Microchip Technology Incorporated in the U.S.A. and other countries. SQTP is a service mark of Microchip Technology Incorporated in the U.S.A. All other trademarks mentioned herein are property of their respective companies. © 2010, Microchip Technology Incorporated, Printed in the U.S.A., All Rights Reserved. Printed on recycled paper. ISBN: 978-1-60932-224-3 Microchip received ISO/TS-16949:2002 certification for its worldwide headquarters, design and wafer fabrication facilities in Chandler and Tempe, Arizona; Gresham, Oregon and design centers in California and India. The Company’s quality system processes and procedures are for its PIC® MCUs and dsPIC® DSCs, KEELOQ® code hopping devices, Serial EEPROMs, microperipherals, nonvolatile memory and analog products. In addition, Microchip’s quality system for the design and manufacture of development systems is ISO 9001:2000 certified. DS39957B-page 2 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 64/80-Pin, High-Performance Microcontrollers with LCD Driver and nanoWatt XLP Technology PIC18F65K90 32K 2K 1K I/O LCD Pixels 53 132 CCP/ ECCP SPI I2C™ RTCC Device Flash SRAM Program Data EEPROM Memory Memory (Bytes) (Bytes) (Bytes) CTMU • Direct LCD Panel Drive Capability: - Can drive LCD panel while in Sleep mode • Up to 48 Segments and 192 Pixels, Software-Selectable • Programmable LCD Timing module: - Multiple LCD timing sources available - Up to four commons: static, 1/2, 1/3 or 1/4 multiplex - Bias configuration: Static, 1/2 or 1/3 • Low-Power Resistor Bias Network for LCD Comparators LCD Driver and Keypad Features: 12-Bit A/D (Channels) • Ten or eight CCP/ECCP modules: - Seven Capture/Compare/PWM (CCP) modules - Three Enhanced Capture/Compare/PWM (ECCP) modules • Eleven 8/16-Bit Timer/Counter modules: - Timer0 – 8/16-bit timer/counter with 8-bit programmable prescaler - Timer1,3,5,7 – 16-bit timer/counter - Timer2,4,6,8,10,12 – 8-bit timer/counter • Three Analog Comparators • Configurable Reference Clock Output • Hardware Real-Time Clock and Calendar (RTCC) module with Clock, Calendar and Alarm Functions - Time-out from 0.5s to 1 year • Charge Time Measurement Unit (CTMU): - Capacitance measurement for mTouch™ Sensing - Time measurement with 1 ns typical resolution • High-Current Sink/Source 25 mA/25 mA (PORTB and PORTC) • Up to Four External Interrupts • Two Master Synchronous Serial Port (MSSP) modules: - 3/4-wire SPI (supports all four SPI modes) - I2C™ Master and Slave mode EUSART Peripheral Highlights: • Power-Managed modes: - Run: CPU on, peripherals on - Idle: CPU off, peripherals on - Sleep: CPU off, peripherals off • Two-Speed Oscillator Start-up • Fail-Safe Clock Monitor • Power-Saving Peripheral Module Disable (PMD) • Ultra Low-Power Wake-up • Fast Wake-up, 2 s Typical • Low-Power WDT, 300 nA Typical • Ultra Low 50 nA Input Leakage • Run mode Currents Down to very low 5.5 A, Typical • Idle mode Currents Down to very low 2.2 A, Typical • Sleep mode Current Down to very low 20 nA, Typical • RTCC Current Down to very low 700 nA, Typical • LCD Current Down to very low 300 nA, Typical Timers 8/16-Bit Low-Power Features: 4/4 5/3 Yes Yes 2 16 3 Y Y PIC18F66K90 64K 4K 1K 53 132 6/5 7/3 Yes Yes 2 16 3 Y Y PIC18F67K90 128K 4K 1K 53 132 6/5 7/3 Yes Yes 2 16 3 Y Y PIC18F85K90 32K 2K 1K 69 192 4/4 5/3 Yes Yes 2 24 3 Y Y PIC18F86K90 64K 4K 1K 69 192 6/5 7/3 Yes Yes 2 24 3 Y Y PIC18F87K90 128K 4K 1K 69 192 6/5 7/3 Yes Yes 2 24 3 Y Y 2010 Microchip Technology Inc. Preliminary DS39957B-page 3 PIC18F87K90 FAMILY Special Microcontroller Features: • • • • • • • • • • • Operating Voltage Range: 1.8V to 5.5V On-Chip 3.3V Regulator Operating Speed up to 64 MHz Up to 128 Kbytes On-Chip Flash Program Memory Data EEPROM of 1,024 Bytes 4K x 8 General Purpose Registers (SRAM) 10,000 Erase/Write Cycle Flash Program Memory, Typical 1,000,000 Erase/write Cycle Data EEPROM Memory, Typical Flash Retention 40 Years, Minimum Three Internal Oscillators: LF-INTRC (31 kHz), MF-INTOSC (500 kHz) and HF-INTOSC (16 MHz) Self-Programmable under Software Control DS39957B-page 4 • Priority Levels for Interrupts • 8 x 8 Single-Cycle Hardware Multiplier • Extended Watchdog Timer (WDT): - Programmable period from 4 ms to 4,194s (about 70 minutes) • In-Circuit Serial Programming™ (ICSP™) via Two Pins • In-Circuit Debug via Two Pins • Programmable: - BOR - LVD • Two Enhanced Addressable USART modules: - LIN/J2602 support - Auto-Baud Detect (ABD) • 12-Bit A/D Converter with up to 24 Channels: - Auto-acquisition and Sleep operation - Differential Input mode of operation Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY Pin Diagrams – PIC18F6XK90 RE2/LCDBIAS3/P2B/CCP10(2) RE3/COM0/P3C/CCP9/REFO RE4/COM1/P3B/CCP8 RE5/COM2/P1C/CCP7 RE6/COM3/P1B/CCP6 RE7/ECCP2(1)/SEG31/P2A RD0/SEG0/CTPLS VDD VSS RD1/SEG1/T5CKI/T7G RD2/SEG2 RD3/SEG3 RD4/SEG4/SDO2 RD5/SEG5/SDI2/SDA2 RD6/SEG6/SCK2/SCL2 RD7/SEG7/SS2 64-Pin QFN, TQFP RE1/LCDBIAS2/P2C RE0/LCDBIAS1/P2D RG0/ECCP3/P3A RG1/TX2/CK2/AN19/C3OUT RG2/RX2/DT2/AN18/C3INA RG3/CCP4/AN17/P3D/C3INB MCLR/RG5 RG4/SEG26/RTCC/T7CKI/T5G/CCP5/AN16/P1D/C3INC VSS VDDCORE/VCAP RF7/AN5/SS1/SEG25 RF6/AN11/SEG24/C1INA RF5/AN10/CVREF/SEG23/C1INB 15 34 16 33 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 RB0/INT0/SEG30/FLTO RB1/INT1/SEG8 RB2/INT2/SEG9/CTED1 RB3/INT3/SEG10/CTED2/P2A RB4/KBI0/SEG11 RB5/KBI1/SEG29/T3CKI/T1G RB6/KBI2/PGC VSS OSC2/CLKO/RA6 OSC1/CLKI/RA7 VDD RB7/KBI3/PGD RC5/SDO1/SEG12 RC4/SDI1/SDA1/SEG16 RC3/SCK1/SCL1/SEG17 RC2/ECCP1/P1A/SEG13 RF1/AN6/C2OUT/SEG19/CTDIN ENVREG AVDD AVSS RA3/AN3/VREF+ RA2/AN2/VREFRA1/AN1/SEG18 RA0/AN0/ULPWU VSS VDD RA5/AN4/T1CKI/SEG15/T3G/HLVDIN RA4/T0CKI/SEG14 RC1/SOSCI/ECCP2(1)/P2A/SEG32 RC0/SOSCO/SCLKI RC6/TX1/CK1/SEG27 RC7/RX1/DT1/SEG28 RF4/AN9/SEG22/C2INA RF3/AN8/SEG21/C2INB/CTMUI RF2/AN7/C1OUT/SEG20 64 63 62 61 60 59 58 57 56 55 54 53 52 51 50 49 1 48 2 47 3 46 45 4 5 44 6 43 PIC18F65K90 7 42 PIC18F66K90 8 41 PIC18F67K90 9 40 10 39 11 38 12 37 13 36 14 35 Note 1: 2: The ECCP2 pin placement depends on the CCP2MX Configuration bit setting. Not available in the PIC18F65K90 and PIC18F85K90. 2010 Microchip Technology Inc. Preliminary DS39957B-page 5 PIC18F87K90 FAMILY Pin Diagrams – PIC18F8XK90 RH1/SEG46/AN22 RH0/SEG47/AN23 RE2/LCDBIAS3/P2B/CCP10(2) RE3/COM0/P3C/CCP9(3)/REFO RE4/COM1/P3B/CCP8(3) RE5/COM2/P1C/CCP7(3) RE6/COM3/P1B/CCP6(3) RE7/ECCP2(1)/P2A/SEG31 RD0/SEG0/CTPLS VDD VSS RD1/SEG1/T5CKI/T7G RD2/SEG2 RD3/SEG3 RD4/SEG4/SDO2 RD5/SEG5/SDI2/SDA2 RD6/SEG6/SCK2/SCL2 RD7/SEG7/SS2 RJ0 RJ1/SEG33 80-Pin TQFP RH2/SEG45/AN21 RH3/SEG44/AN20 RE1/LCDBIAS2/P2C RE0/LCDBIAS1/P2D RG0/ECCP3/P3A RG1/TX2/CK2/AN19/C3OUT RG2/RX2/DT2/AN18/C3INA RG3/CCP4/AN17/P3D/C3INB MCLR/RG5 RG4/SEG26/RTCC/T7CKI/T5G/CCP5/AN16/P1D/C3INC VSS VDDCORE/VCAP RF7/AN5/SS1/SEG25 RF6/AN11/SEG24/C1INA RF5/AN10/CVREF/SEG23/C1INB RF4/AN9/SEG22/C2INA RF3/AN8/SEG21/C2INB/CTMUI RF2/AN7/C1OUT/SEG20 RH7/SEG43/CCP6(3)/P1B/AN15 RH6/SEG42/CCP7(3)/P1C/AN14/C1INC 80 79 78 77 76 75 74 73 72 71 70 69 68 6766 65 64 63 62 61 60 59 58 57 56 55 54 53 PIC18F85K90 52 51 PIC18F86K90 50 PIC18F87K90 49 48 47 46 45 44 43 42 41 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 RJ2/SEG34 RJ3/SEG35 RB0/INT0/SEG30/FLT0 RB1/INT1/SEG8 RB2/INT2/SEG9/CTED1 RB3/INT3/SEG10/CTED2/P2A RB4/KBI0/SEG11 RB5/KBI1/SEG29/T3CKI/T1G RB6/KBI2/PGC VSS OSC2/CLKO/RA6 OSC1/CLKI/RA7 VDD RB7/KBI3/PGD RC5/SDO1/SEG12 RC4/SDI1/SDA1/SEG16 RC3/SCK1/SCL1/SEG17 RC2/ECCP1/P1A/SEG13 RJ7/SEG36 RJ6/SEG37 RH5/SEG41/CCP8(3)/P3B/AN13/C2IND RH4/SEG40/CCP9(3)/P3C/AN12/C2INC RF1/AN6/C2OUT/SEG19/CTDIN ENVREG AVDD AVSS RA3/AN3/VREF+ RA2/AN2/VREFRA1/AN1/SEG18 RA0/AN0/ULPWU VSS VDD RA5/AN4/T1CKI/SEG15/T3G/HLVDIN RA4/T0CKI/SEG14 RC1/SOSCI/ECCP2(1)I/SEG32/P2A RC0/SOSCO/SCKLI RC6/TX1/CK1/SEG27 RC7/RX1/DT1/SEG28 RJ4/SEG39 RJ5/SEG38 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 Note 1: The ECCP2 pin placement depends on the CCP2MX Configuration bit setting. 2: Not available in the PIC18F65K90 and PIC18F85K90. 3: The CCP6, CCP7, CCP8 and CCP9 pin placement depends on the ECCPMX Configuration bit setting DS39957B-page 6 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY Table of Contents 1.0 Device Overview .......................................................................................................................................................................... 9 2.0 Guidelines for Getting Started with PIC18FXXKXX Microcontrollers ......................................................................................... 35 3.0 Oscillator Configurations ............................................................................................................................................................ 39 4.0 Power-Managed Modes ............................................................................................................................................................. 51 5.0 Reset .......................................................................................................................................................................................... 67 6.0 Memory Organization ................................................................................................................................................................. 83 7.0 Flash Program Memory............................................................................................................................................................ 109 8.0 Data EEPROM Memory ........................................................................................................................................................... 119 9.0 8 x 8 Hardware Multiplier.......................................................................................................................................................... 125 10.0 Interrupts .................................................................................................................................................................................. 127 11.0 I/O Ports ................................................................................................................................................................................... 151 12.0 Timer0 Module ......................................................................................................................................................................... 181 13.0 Timer1 Module ......................................................................................................................................................................... 185 14.0 Timer2 Module ......................................................................................................................................................................... 197 15.0 Timer3/5/7 Modules.................................................................................................................................................................. 199 16.0 Timer4/6/8/10/12 Modules........................................................................................................................................................ 211 17.0 Real-Time Clock and Calendar (RTCC)................................................................................................................................... 215 18.0 Capture/Compare/PWM (CCP) Modules ................................................................................................................................. 235 19.0 Enhanced Capture/Compare/PWM (ECCP) Module................................................................................................................ 249 20.0 Liquid Crystal Display (LCD) Driver Module............................................................................................................................. 271 21.0 Master Synchronous Serial Port (MSSP) Module .................................................................................................................... 301 22.0 Enhanced Universal Synchronous Asynchronous Receiver Transmitter (EUSART) ............................................................... 347 23.0 12-Bit Analog-to-Digital Converter (A/D) Module ..................................................................................................................... 371 24.0 Comparator Module.................................................................................................................................................................. 387 25.0 Comparator Voltage Reference Module................................................................................................................................... 395 26.0 High/Low-Voltage Detect (HLVD)............................................................................................................................................. 399 27.0 Charge Time Measurement Unit (CTMU) ................................................................................................................................ 405 28.0 Special Features of the CPU.................................................................................................................................................... 423 29.0 Instruction Set Summary .......................................................................................................................................................... 449 30.0 Development Support............................................................................................................................................................... 499 31.0 Electrical Characteristics .......................................................................................................................................................... 503 32.0 Packaging Information.............................................................................................................................................................. 541 Appendix A: Revision History............................................................................................................................................................. 549 Appendix B: Migration From PIC18F85J90 and PIC18F87J90 to PIC18F87K90 .............................................................................. 549 Index ................................................................................................................................................................................................. 551 The Microchip Web Site ..................................................................................................................................................................... 563 Customer Change Notification Service .............................................................................................................................................. 563 Customer Support .............................................................................................................................................................................. 563 Reader Response .............................................................................................................................................................................. 564 Product Identification System ............................................................................................................................................................ 565 2010 Microchip Technology Inc. Preliminary DS39957B-page 7 PIC18F87K90 FAMILY TO OUR VALUED CUSTOMERS It is our intention to provide our valued customers with the best documentation possible to ensure successful use of your Microchip products. To this end, we will continue to improve our publications to better suit your needs. Our publications will be refined and enhanced as new volumes and updates are introduced. If you have any questions or comments regarding this publication, please contact the Marketing Communications Department via E-mail at [email protected] or fax the Reader Response Form in the back of this data sheet to (480) 792-4150. We welcome your feedback. Most Current Data Sheet To obtain the most up-to-date version of this data sheet, please register at our Worldwide Web site at: http://www.microchip.com You can determine the version of a data sheet by examining its literature number found on the bottom outside corner of any page. The last character of the literature number is the version number, (e.g., DS30000A is version A of document DS30000). Errata An errata sheet, describing minor operational differences from the data sheet and recommended workarounds, may exist for current devices. As device/documentation issues become known to us, we will publish an errata sheet. The errata will specify the revision of silicon and revision of document to which it applies. To determine if an errata sheet exists for a particular device, please check with one of the following: • Microchip’s Worldwide Web site; http://www.microchip.com • Your local Microchip sales office (see last page) When contacting a sales office, please specify which device, revision of silicon and data sheet (include literature number) you are using. Customer Notification System Register on our web site at www.microchip.com to receive the most current information on all of our products. DS39957B-page 8 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 1.0 DEVICE OVERVIEW This document contains device-specific information for the following devices: • PIC18F65K90 • PIC18F66K90 • PIC18F67K90 • PIC18F85K90 • PIC18F86K90 • PIC18F87K90 This family combines the traditional advantages of all PIC18 microcontrollers – namely, high computational performance and a rich feature set – with a versatile on-chip LCD driver, while maintaining an extremely competitive price point. These features make the PIC18F87K90 family a logical choice for many high-performance applications where price is a primary consideration. 1.1 1.1.1 Core Features nanoWatt TECHNOLOGY All of the devices in the PIC18F87K90 family incorporate a range of features that can significantly reduce power consumption during operation. Key items include: • Alternate Run Modes: By clocking the controller from the Timer1 source or the internal RC oscillator, power consumption during code execution can be reduced. • Multiple Idle Modes: The controller can also run with its CPU core disabled but the peripherals still active. In these states, power consumption can be reduced even further. • On-the-Fly Mode Switching: The power-managed modes are invoked by user code during operation, allowing the user to incorporate power-saving ideas into their application’s software design. • nanoWatt XLP: An extra low-power BOR, RTCC and low-power Watchdog Timer. Also, an ultra low-power regulator for Sleep mode is provided in regulator enabled modes. 1.1.2 OSCILLATOR OPTIONS AND FEATURES All of the devices in the PIC18F87K90 family offer different oscillator options, allowing users a range of choices in developing application hardware. These include: • External Resistor/Capacitor (RC); RA6 available • External Resistor/Capacitor with Clock Out (RCIO) • Three External Clock modes: - External Clock (EC); RA6 available - External Clock with Clock Out (ECIO) - External Crystal (XT, HS, LP) • A Phase Lock Loop (PLL) frequency multiplier, available to the External Oscillator modes which allows clock speeds of up to 64 MHz. PLL can also be used with the internal oscillator. 2010 Microchip Technology Inc. • An internal oscillator block that provides a 16 MHz clock (±2% accuracy) and an INTRC source (approximately 31 kHz, stable over temperature and VDD) - Operates as HF-INTOSC or MF-INTOSC when block selected for 16 MHz or 500 kHz - Frees the two oscillator pins for use as additional general purpose I/O The internal oscillator block provides a stable reference source that gives the family additional features for robust operation: • Fail-Safe Clock Monitor: This option constantly monitors the main clock source against a reference signal provided by the internal oscillator. If a clock failure occurs, the controller is switched to the internal oscillator, allowing for continued low-speed operation or a safe application shutdown. • Two-Speed Start-up: This option allows the internal oscillator to serve as the clock source from Power-on Reset, or wake-up from Sleep mode, until the primary clock source is available. 1.1.3 MEMORY OPTIONS The PIC18F87K90 family provides ample room for application code, from 32 Kbytes to 128 Kbytes of code space. The Flash cells for program memory are rated to last up to 10,000 erase/write cycles. Data retention without refresh is conservatively estimated to be greater than 40 years. The Flash program memory is readable and writable. During normal operation, the PIC18F87K90 family also provides plenty of room for dynamic application data with up to 3,828 bytes of data RAM. 1.1.4 EXTENDED INSTRUCTION SET The PIC18F87K90 family implements the optional extension to the PIC18 instruction set, adding 8 new instructions and an Indexed Addressing mode. Enabled as a device configuration option, the extension has been specifically designed to optimize re-entrant application code originally developed in high-level languages, such as ‘C’. 1.1.5 EASY MIGRATION Regardless of the memory size, all devices share the same rich set of peripherals (except the 32-Kbyte parts, which have two less CCPs and three less Timers), allowing for a smooth migration path as applications grow and evolve. The consistent pinout scheme, used throughout the entire family, also aids in migrating to the next larger device. This is true when moving between the 64-pin members, between the 80-pin members, or even jumping from 64-pin to 80-pin devices. Preliminary DS39957B-page 9 PIC18F87K90 FAMILY The PIC18F87K90 family is also largely pin-compatible with other PIC18 families, such as the PIC18F8720, PIC18F8722, PIC18F85J11, PIC18F8490, PIC18F85J90, PIC18F87J90 and PIC18F87J93 families of microcontrollers with LCD drivers. This allows a new dimension to the evolution of applications, allowing developers to select different price points within Microchip’s PIC18 portfolio, while maintaining a similar feature set. 1.2 LCD Driver The on-chip LCD driver includes many features that ease the integration of displays in low-power applications. These include an integrated internal resistor ladder, so bias voltages can be generated internally. This enables software-controlled contrast control and eliminates the need for external bias voltage resistors. 1.3 Other Special Features • Communications: The PIC18F87K90 family incorporates a range of serial communication peripherals including two Enhanced USART, that support LIN/J2602, and two Master SSP modules capable of both SPI and I2C™ (Master and Slave) modes of operation. • CCP Modules: PIC18F87K90 family devices incorporate up to seven or five Capture/ Compare/PWM (CCP) modules. Up to six different time bases can be used to perform several different operations at once. • ECCP Modules: The PIC18F87K90 family has three Enhanced CCP (ECCP) modules to maximize flexibility in control applications: - Up to eight different time bases for performing several different operations at once - Up to four PWM outputs for each module, for a total of 12 PWMs - Other beneficial features, such as polarity selection, programmable dead time, auto-shutdown and restart, and Half-Bridge and Full-Bridge Output modes • 12-Bit A/D Converter: The PIC18F87K90 family has differential ADC. It incorporates programmable acquisition time, allowing for a channel to be selected and a conversion to be initiated without waiting for a sampling period, and thus, reducing code overhead. • Charge Time Measurement Unit (CTMU): The CTMU is a flexible analog module that provides accurate differential time measurement between pulse sources, as well as asynchronous pulse generation. Together with other on-chip analog modules, the CTMU can precisely measure time, measure capacitance or relative changes in capacitance, or generate output pulses that are independent of the system clock. DS39957B-page 10 • LP Watchdog Timer (WDT): This enhanced version incorporates a 22-bit prescaler, allowing an extended time-out range that is stable across operating voltage and temperature. See Section 31.0 “Electrical Characteristics” for time-out periods. • Real-Time Clock and Calendar Module (RTCC): The RTCC module is intended for applications requiring that accurate time be maintained for extended periods of time with minimum to no intervention from the CPU. The module is a 100-year clock and calendar with automatic leap year detection. The range of the clock is from 00:00:00 (midnight) on January 1, 2000 to 23:59:59 on December 31, 2099. 1.4 Details on Individual Family Members Devices in the PIC18F87K90 family are available in 64-pin and 80-pin packages. Block diagrams for the two groups are shown in Figure 1-1 and Figure 1-2. The devices are differentiated from each other in these ways: • Flash Program Memory – - PIC18FX5K90 (PIC18F65K90 and PIC18F85K90) – 32 Kbytes - PIC18FX6K90 (PIC18F66K90 and PIC18F86K90) – 64 Kbytes - PIC18FX7K90 (PIC18F67K90 and PIC18F87K90) – 128 Kbytes • Data RAM - All devices except PIC18FX5K90 – 4 Kbytes - PIC18FX5K90 – 2 Kbytes • I/O Ports - PIC18F6XK90 (64-pin devices) – Seven bidirectional ports - PIC18F8XK90 (80-pin devices) – Nine bidirectional ports • LCD Pixels: - PIC18F6XK90 – 132 pixels (33 SEGs x 4 COMs) - PIC18F8XK90 – 192 pixels (48 SEGs x 4 COMs) • CCP Module - All devices except PIC18FX5K90 have seven CCP modules, PIC18FX5K90 has only five CCP modules • Timers - All devices except 18FX5K90 have six 8-bit timers and five 16-bit timers, PIC18FX5K90 has only four 8-bit timers and four 16-bit timers. • A/D Channels - All PIC18F8XK90 devices have 24 A/D channels, all PIC18F6XK90 devices have 16 A/D channels All other features for devices in this family are identical. These are summarized in Table 1-1 and Table 1-2. The pinouts for all devices are listed in Table 1-3 and Table 1-4. Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY TABLE 1-1: DEVICE FEATURES FOR THE PIC18F6XK90 (64-PIN DEVICES) Features PIC18F65K90 PIC18F66K90 Operating Frequency Program Memory (Bytes) Program Memory (Instructions) PIC18F67K90 DC – 64 MHz 32K 64K 128K 16,384 32,768 65,536 Data Memory (Bytes) 2K 4K 4K Interrupt Sources 42 48 I/O Ports Ports A, B, C, D, E, F, G LCD Driver (available pixels to drive) Timers 132 (33 SEGs x 4 COMs) 8 11 Comparators 3 CTMU Yes RTCC Yes Capture/Compare/PWM (CCP) Modules 5 7 Enhanced CCP (ECCP) Modules Serial Communications 3 Two MSSP and two Enhanced USART (EUSART) 12-Bit Analog-to-Digital Module Resets (and Delays) Instruction Set 7 16 Input Channels POR, BOR, RESET Instruction, Stack Full, Stack Underflow, MCLR, WDT (PWRT, OST) 75 Instructions, 83 with Extended Instruction Set Enabled Packages 64-Pin QFN, 64-Pin TQFP TABLE 1-2: DEVICE FEATURES FOR THE PIC18F8XK90 (80-PIN DEVICES) Features PIC18F85K90 PIC18F86K90 Operating Frequency Program Memory (Bytes) PIC18F87K90 DC – 64 MHz 32K 64K 128K 16,384 32,768 65,536 Data Memory (Bytes) 2K 4K Interrupt Sources 42 Program Memory (Instructions) I/O Ports Ports A, B, C, D, E, F, G, H, J LCD Driver (available pixels to drive) Timers 192 (48 SEGs x 4 COMs) 8 11 Comparators 3 CTMU Yes RTCC Yes Capture/Compare/PWM (CCP) Modules 5 Enhanced CCP (ECCP) Modules Serial Communications Instruction Set 7 Two MSSP and two Enhanced USART (EUSART) 24 Input Channels POR, BOR, RESET Instruction, Stack Full, Stack Underflow, MCLR, WDT (PWRT, OST) 75 Instructions, 83 with Extended Instruction Set Enabled Packages 2010 Microchip Technology Inc. 7 3 12-Bit Analog-to-Digital Module Resets (and Delays) 4K 48 80-Pin TQFP Preliminary DS39957B-page 11 PIC18F87K90 FAMILY FIGURE 1-1: PIC18F6XK90 (64-PIN) BLOCK DIAGRAM Data Bus<8> Table Pointer<21> 20 Address Latch PCU PCH PCL Program Counter 12 Data Address<12> 31-Level Stack 4 BSR Address Latch Program Memory STKPTR 12 PORTC RC0:RC7(1) inc/dec logic Table Latch Instruction Bus <16> PORTB RB0:RB7(1) 4 Access Bank 12 FSR0 FSR1 FSR2 Data Latch 8 RA0:RA7(1,2) Data Memory (2/4 Kbytes) PCLATU PCLATH 21 PORTA Data Latch 8 8 inc/dec logic Address Decode ROM Latch PORTD RD0:RD7(1) IR OSC2/CLKO OSC1/CLKI PRODH PRODL Power-up Timer INTRC Oscillator 16 MHz Oscillator Oscillator Start-up Timer 8 BITOP W 8 8 8 8 Power-on Reset PORTE RE0:RE7(1) 8 x 8 Multiply 3 Timing Generation Precision Band Gap Reference ENVREG 8 State Machine Control Signals Instruction Decode and Control PORTF 8 RF1:RF7(1) ALU<8> Watchdog Timer 8 BOR and LVD Voltage Regulator PORTG RG0:RG5(1) VDDCORE/VCAP VDD, VSS MCLR Timer0 Timer1 Timer 2/4/6/8/10(3)/12(3) Timer 3/5/7(3) CTMU ADC 12-Bit Comparator 1/2/3 CCP 4/5/6/7/8/9(3)/10(3) ECCP 1/2/3 EUSART1 EUSART2 RTCC MSSP1/2 LCD Driver Note 1: See Table 1-3 for I/O port pin descriptions. 2: RA6 and RA7 are only available as digital I/O in select oscillator modes. For more information, see Section 3.0 “Oscillator Configurations”. 3: Unimplemented on the PIC18F65K90. DS39957B-page 12 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY FIGURE 1-2: PIC18F8XK90 (80-PIN) BLOCK DIAGRAM Data Bus<8> Table Pointer<21> 20 Address Latch PCU PCH PCL Program Counter 31-Level Stack 4 BSR STKPTR PORTC RC0:RC7(1) 12 inc/dec logic Table Latch Instruction Bus <16> RB0:RB7(1) 4 Access Bank 12 FSR0 FSR1 FSR2 Data Latch 8 PORTB 12 Data Address<12> Address Latch Program Memory RA0:RA7(1,2) Data Memory (2/4 Kbytes) PCLATU PCLATH 21 PORTA Data Latch 8 8 inc/dec logic PORTD RD0:RD7(1) Address Decode ROM Latch PORTE RE0:RE7 IR OSC2/CLKO OSC1/CLKI ENVREG 8 State Machine Control Signals Instruction Decode and Control PORTF PRODH PRODL 3 Timing Generation Power-up Timer INTRC Oscillator 16 MHz Oscillator Oscillator Start-up Timer Precision Band Gap Reference Watchdog Timer Voltage Regulator BOR and LVD 8 x 8 Multiply 8 BITOP W 8 8 8 8 Power-on Reset RF1:RF7(1) PORTG RG0:RG5(1) 8 ALU<8> PORTH RH0:RH7(1) 8 PORTJ VDDCORE/VCAP VDD,VSS RJ0:RJ7(1) MCLR Timer0 Timer1 Timer 2/4/6/8/10(3)/12(3) Timer 3/5/7(3) CTMU ADC 12-Bit Comparator 1/2/3 CCP 4/5/6/7/8/9(3)/10(3) ECCP 1/2/3 EUSART1 EUSART2 RTCC MSSP1/2 LCD Driver Note 1: See Table 1-3 for I/O port pin descriptions. 2: RA6 and RA7 are only available as digital I/O in select oscillator modes. See Section 3.0 “Oscillator Configurations” for more information. 3: Unimplemented on the PIC18F85K90. 2010 Microchip Technology Inc. Preliminary DS39957B-page 13 PIC18F87K90 FAMILY TABLE 1-3: PIC18F6XK90 PINOUT I/O DESCRIPTIONS Pin Name MCLR/RG5 MCLR Pin Number QFN/TQFP Pin Buffer Type Type 7 I ST I ST I I CMOS CMOS I/O TTL O — CLKO O — RA6 I/O TTL RG5 OSC1/CLKI/RA7 OSC1 CLKI 39 RA7 OSC2/CLKO/RA6 OSC2 Description 40 Master Clear (input) or programming voltage (input). This pin is an active-low Reset to the device. General purpose, input only pin. Oscillator crystal or external clock input. Oscillator crystal input. External clock source input. Always associated with pin function, OSC1. (See related OSC1/CLKI, OSC2/CLKO pins.) General purpose I/O pin. Oscillator crystal or clock output. Oscillator crystal output. Connects to crystal or resonator in Crystal Oscillator mode. In certain oscillator modes, OSC2 pin outputs CLKO, which has 1/4 the frequency of OSC1 and denotes the instruction cycle rate. General purpose I/O pin. Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output ST = Schmitt Trigger input with CMOS levels Analog = Analog input I = Input O = Output P = Power OD = Open-Drain (no P diode to VDD) I2C™ = I2C/SMBus Note 1: Default assignment for ECCP2 when the CCP2MX Configuration bit is set. 2: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared. 3: Not available on PIC18F65K90 and PIC18F85K90 devices. DS39957B-page 14 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY TABLE 1-3: PIC18F6XK90 PINOUT I/O DESCRIPTIONS (CONTINUED) Pin Name Pin Number QFN/TQFP Pin Buffer Type Type Description PORTA is a bidirectional I/O port. RA0/AN0/ULPWU RA0 AN0 ULPWU 24 RA1/AN1/SEG18 RA1 AN1 SEG18 23 RA2/AN2/VREFRA2 AN2 VREF- 22 RA3/AN3/VREF+ RA3 AN3 VREF+ 21 RA4/T0CKI/SEG14 RA4 T0CKI SEG14 28 RA5/AN4/SEG15/T1CKI/ T3G/HLVDIN RA5 AN4 SEG15 T1CKI T3G HLVDIN 27 I/O I I TTL Analog Analog Digital I/O. Analog Input 0. Ultra low-power wake-up input. I/O I O TTL Analog Analog Digital I/O. Analog Input 1. SEG18 output for LCD. I/O I I TTL Analog Analog Digital I/O. Analog Input 2. A/D reference voltage (low) input. I/O I I TTL Analog Analog Digital I/O. Analog Input 3. A/D reference voltage (high) input. I/O I O ST ST Analog Digital I/O. Timer0 external clock input. SEG14 output for LCD. I/O I O I I I TTL Analog Analog ST ST Analog Digital I/O. Analog Input 4. SEG15 output for LCD. Timer1 clock input. Timer3 external clock gate input. High/Low-Voltage Detect (HLVD) input. RA6 See the OSC2/CLKO/RA6 pin. RA7 See the OSC1/CLKI/RA7 pin. Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output ST = Schmitt Trigger input with CMOS levels Analog = Analog input I = Input O = Output P = Power OD = Open-Drain (no P diode to VDD) I2C™ = I2C/SMBus Note 1: Default assignment for ECCP2 when the CCP2MX Configuration bit is set. 2: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared. 3: Not available on PIC18F65K90 and PIC18F85K90 devices. 2010 Microchip Technology Inc. Preliminary DS39957B-page 15 PIC18F87K90 FAMILY TABLE 1-3: PIC18F6XK90 PINOUT I/O DESCRIPTIONS (CONTINUED) Pin Name Pin Number QFN/TQFP Pin Buffer Type Type Description PORTB is a bidirectional I/O port. PORTB can be software programmed for internal weak pull-ups on all inputs. RB0/INT0/SEG30/FLTO RB0 INT0 SEG30 FLTO 48 RB1/INT1/SEG8 RB1 INT1 SEG8 47 RB2/INT2/SEG9/CTED1 RB2 INT2 CTED1 SEG9 46 RB3/INT3/SEG10/CTED2/ ECCP2/P2A RB3 INT3 SEG10 CTED2 ECCP2 P2A 45 RB4/KBI0/SEG11 RB4 KBI0 SEG11 44 RB5/KBI1/SEG29/T3CKI/ T1G RB5 KBI1 SEG29 T3CKI T1G 43 RB6/KBI2/PGC RB6 KBI2 PGC 42 RB7/KBI3/PGD RB7 KBI3 PGD 37 I/O I O I TTL ST Analog ST Digital I/O. External Interrupt 0. SEG30 output for LCD. Enhanced PWM Fault input for ECCP1/2/3. I/O I O TTL ST Analog Digital I/O. External Interrupt 1. SEG8 output for LCD. I/O I I O TTL ST ST Analog Digital I/O. External Interrupt 2. CTMU Edge 1 input. SEG9 output for LCD. I/O I O I I/O O TTL ST Analog ST ST — Digital I/O. External Interrupt 3. SEG10 output for LCD. CTMU Edge 2 input. Capture 2 input/Compare 2 output/PWM2. Enhanced PWM2 Output A. I/O I O TTL TTL Analog Digital I/O. Interrupt-on-change pin. SEG11 output for LCD. I/O I O I I TTL TTL Analog ST ST Digital I/O. Interrupt-on-change pin. SEG29 output for LCD. Timer3 clock input. Timer1 external clock gate input. I/O I I/O TTL TTL ST Digital I/O. Interrupt-on-change pin. In-Circuit Debugger and ICSP™ programming clock pin. I/O I I/O TTL TTL ST Digital I/O. Interrupt-on-change pin. In-Circuit Debugger and ICSP programming data pin. Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output ST = Schmitt Trigger input with CMOS levels Analog = Analog input I = Input O = Output P = Power OD = Open-Drain (no P diode to VDD) I2C™ = I2C/SMBus Note 1: Default assignment for ECCP2 when the CCP2MX Configuration bit is set. 2: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared. 3: Not available on PIC18F65K90 and PIC18F85K90 devices. DS39957B-page 16 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY TABLE 1-3: PIC18F6XK90 PINOUT I/O DESCRIPTIONS (CONTINUED) Pin Name Pin Number QFN/TQFP Pin Buffer Type Type Description PORTC is a bidirectional I/O port. RC0/SOSCO/SCLKI RC0 SOSCO SCLKI 30 RC1/SOSCI/ECCP2/P2A/ SEG32 RC1 SOSCI ECCP2(1) P2A SEG32 29 RC2/ECCP1/P1A/SEG13 RC2 ECCP1 P1A SEG13 33 RC3/SCK1/SCL1/SEG17 RC3 SCK1 SCL1 SEG17 34 RC4/SDI1/SDA1/SEG16 RC4 SDI1 SDA1 SEG16 35 RC5/SDO1/SEG12 RC5 SDO1 SEG12 36 RC6/TX1/CK1/SEG27 RC6 TX1 CK1 SEG27 31 RC7/RX1/DT1/SEG28 RC7 RX1 DT1 SEG28 32 I/O O I ST — ST I/O I I/O O O ST CMOS ST — Analog Digital I/O. SOSC oscillator input. Capture 2 input/Compare 2 output/PWM2 output. Enhanced PWM2 Output A. SEG32 output for LCD. I/O I/O O O ST ST — Analog Digital I/O. Capture 1 input/Compare 1 output/PWM1 output. Enhanced PWM1 Output A. SEG13 output for LCD. I/O I/O I/O O ST ST I2C Analog Digital I/O. Synchronous serial clock input/output for SPI mode. Synchronous serial clock input/output for I2C™ mode. SEG17 output for LCD. I/O I I/O O ST ST I2C Analog Digital I/O. SPI data in. I2C data I/O. SEG16 output for LCD. I/O O O ST — Analog Digital I/O. SPI data out. SEG12 output for LCD. I/O O I/O O ST — ST Analog Digital I/O. EUSART asynchronous transmit. EUSART synchronous clock (see related RX1/DT1). SEG27 output for LCD. I/O I I/O O ST ST ST Analog Digital I/O. EUSART asynchronous receive. EUSART synchronous data (see related TX1/CK1). SEG28 output for LCD. Digital I/O. SOSC oscillator output. Digital SOSC input. Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output ST = Schmitt Trigger input with CMOS levels Analog = Analog input I = Input O = Output P = Power OD = Open-Drain (no P diode to VDD) I2C™ = I2C/SMBus Note 1: Default assignment for ECCP2 when the CCP2MX Configuration bit is set. 2: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared. 3: Not available on PIC18F65K90 and PIC18F85K90 devices. 2010 Microchip Technology Inc. Preliminary DS39957B-page 17 PIC18F87K90 FAMILY TABLE 1-3: PIC18F6XK90 PINOUT I/O DESCRIPTIONS (CONTINUED) Pin Name Pin Number QFN/TQFP Pin Buffer Type Type Description PORTD is a bidirectional I/O port. RD0/SEG0/CTPLS RD0 SEG0 CTPLS 58 RD1/SEG1/T5CKI/T7G RD1 SEG1 T5CKI T7G 55 RD2/SEG2 RD2 SEG2 54 RD3/SEG3 RD3 SEG3 53 RD4/SEG4/SDO2 RD4 SEG4 SDO2 52 RD5/SEG5/SDI2/SDA2 RD5 SEG5 SDI2 SDA2 51 RD6/SEG6/SCK2/SCL2 RD6 SEG6 SCK2 SCL2 50 RD7/SEG7/SS2 RD7 SEG7 SS2 49 I/O O O ST Analog — Digital I/O. SEG0 output for LCD. CTMU pulse generator output. I/O O I I ST Analog ST ST Digital I/O. SEG1 output for LCD. Timer5 clock input. Timer7 external clock gate input. I/O O ST Analog Digital I/O. SEG2 output for LCD. I/O O ST Analog Digital I/O. SEG3 output for LCD. I/O O O ST Analog — Digital I/O. SEG4 output for LCD. SPI data out. I/O O I I/O ST Analog ST I2C Digital I/O. SEG5 output for LCD. SPI data in. I2C™ data I/O. I/O O I/O I/O ST Analog ST I2C Digital I/O. SEG6 output for LCD. Synchronous serial clock. Synchronous serial clock for I2C mode. I/O O I ST Analog TTL Digital I/O. SEG7 output for LCD. SPI slave select input. Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output ST = Schmitt Trigger input with CMOS levels Analog = Analog input I = Input O = Output P = Power OD = Open-Drain (no P diode to VDD) I2C™ = I2C/SMBus Note 1: Default assignment for ECCP2 when the CCP2MX Configuration bit is set. 2: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared. 3: Not available on PIC18F65K90 and PIC18F85K90 devices. DS39957B-page 18 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY TABLE 1-3: PIC18F6XK90 PINOUT I/O DESCRIPTIONS (CONTINUED) Pin Name Pin Number QFN/TQFP Pin Buffer Type Type Description PORTE is a bidirectional I/O port. RE0/LCDBIAS1/P2D RE0 LCDBIAS1 P2D 2 RE1/LCDBIAS2/P2C RE1 LCDBIAS2 P2C 1 RE2/LCDBIAS3/P2B/ CCP10 RE2 LCDBIAS3 P2B CCP10(3) 64 RE3/COM0/P3C/CCP9/ REFO RE3 COM0 P3C CCP9(3) REFO 63 RE4/COM1/P3B/CCP8 RE4 COM1 P3B CCP8 62 RE5/COM2/P1C/CCP7 RE5 COM2 P1C CCP7 61 RE6/COM3/P1B/CCP6 RE6 COM3 P1B CCP6 60 RE7/ECCP2/SEG31/P2A RE7 ECCP2(2) SEG31 P2A 59 I/O I O ST Analog — Digital I/O. BIAS1 input for LCD. EECP2 PWM Output D. I/O I O ST Analog — Digital I/O. BIAS2 input for LCD. ECCP2 PWM Output C. I/O I O I/O ST Analog — S/T Digital I/O. BIAS3 input for LCD. ECCP2 PWM Output B. Capture 10 input/Compare 10 output/PWM10 output. I/O O O I/O O ST Analog — S/T — Digital I/O. COM0 output for LCD. ECCP3 PWM Output C. Capture 9 input/Compare 9 output/PWM9 output. Reference clock out. I/O O O I/O ST Analog — S/T Digital I/O. COM1 output for LCD. ECCP3 PWM Output B. Capture 8 input/Compare 8 output/PWM8 output. I/O O O I/O ST Analog — S/T Digital I/O. COM2 output for LCD. ECCP1 PWM Output C. Capture 7 input/Compare 7 output/PWM7 output. I/O O O I/O ST Analog — S/T Digital I/O. COM3 output for LCD. ECCP1 PWM Output B. Capture 6 input/Compare 6 output/PWM6 output. I/O I/O O O ST ST Analog — Digital I/O. Capture 2 input/Compare 2 output/PWM2 output. SEG31 Output for LCD. ECCP2 PWM output A. Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output ST = Schmitt Trigger input with CMOS levels Analog = Analog input I = Input O = Output P = Power OD = Open-Drain (no P diode to VDD) I2C™ = I2C/SMBus Note 1: Default assignment for ECCP2 when the CCP2MX Configuration bit is set. 2: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared. 3: Not available on PIC18F65K90 and PIC18F85K90 devices. 2010 Microchip Technology Inc. Preliminary DS39957B-page 19 PIC18F87K90 FAMILY TABLE 1-3: PIC18F6XK90 PINOUT I/O DESCRIPTIONS (CONTINUED) Pin Name Pin Number QFN/TQFP Pin Buffer Type Type Description PORTF is a bidirectional I/O port. RF1/AN6/C2OUT/SEG19/ CTDIN RF1 AN6 C2OUT SEG19 CTDIN 17 RF2/AN7/C1OUT/SEG20 RF2 AN7 C1OUT SEG20 16 RF3/AN8/SEG21/C2INB/ CTMUI RF3 AN8 SEG21 C2INB CTMUI 15 RF4/AN9/SEG22/C2INA RF4 AN9 SEG22 C2INA 14 RF5/AN10/CVREF/ SEG23/C1INB RF5 AN10 CVREF SEG23 C1INB 13 RF6/AN11/SEG24/C1INA RF6 AN11 SEG24 C1INA 12 RF7/AN5/SS1/SEG25 RF7 AN5 SS1 SEG25 11 I/O I O O I ST Analog — Analog ST Digital I/O. Analog Input 6. Comparator 2 output. SEG19 output for LCD. CTMU pulse delay input. I/O I O O ST Analog — Analog Digital I/O. Analog Input 7. Comparator 1 output. SEG20 output for LCD. I/O I O I O ST Analog Analog Analog — Digital I/O. Analog Input 8. SEG21 output for LCD. Comparator 2 Input B. CTMU pulse generator charger for the C2INB comparator input. I/O I O I ST Analog Analog Analog Digital I/O. Analog Input 9. SEG22 output for LCD Comparator 2 Input A. I/O I O O I ST Analog Analog Analog Analog Digital I/O. Analog Input 10. Comparator reference voltage output. SEG23 output for LCD. Comparator 1 Input B. I/O I O I ST Analog Analog Analog Digital I/O. Analog Input 11. SEG24 output for LCD Comparator 1 Input A. I/O ST O AnalogT I TL O Analog Digital I/O. Analog Input 5. SPI1 slave select input. SEG25 output for LCD. Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output ST = Schmitt Trigger input with CMOS levels Analog = Analog input I = Input O = Output P = Power OD = Open-Drain (no P diode to VDD) I2C™ = I2C/SMBus Note 1: Default assignment for ECCP2 when the CCP2MX Configuration bit is set. 2: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared. 3: Not available on PIC18F65K90 and PIC18F85K90 devices. DS39957B-page 20 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY TABLE 1-3: PIC18F6XK90 PINOUT I/O DESCRIPTIONS (CONTINUED) Pin Name Pin Number QFN/TQFP Pin Buffer Type Type Description PORTG is a bidirectional I/O port. RG0/ECCP3/P3A RG0 ECCP3 P3A 3 RG1/TX2/CK2/AN19/ C3OUT RG1 TX2 CK2 AN19 C3OUT 4 RG2/RX2/DT2/AN18/ C3INA RG2 RX2 DT2 AN18 C3INA 5 RG3/CCP4/AN17/P3D/ C3INB RG3 CCP4 AN17 P3D C3INB 6 RG4/SEG26/RTCC/ T7CKI/T5G/CCP5/AN16/ P1D/C3INC RG4 SEG26 RTCC T7CKI(3) T5G CCP5 AN16 P1D C3INC 8 RG5 7 I/O I/O O ST ST — I/O O I/O I O ST — ST Analog — Digital I/O. USART asynchronous transmit. USART synchronous clock (see related RX2/DT2). Analog Input 19. Comparator 3 output. I/O I I/O I I ST ST ST Analog Analog Digital I/O. EUSART asynchronous receive. EUSART synchronous data (see related TX2/CK2). Analog Input 18. Comparator 3 Input A. I/O I/O I O I ST S/T Analog — Analog Digital I/O. Capture 4 input/Compare 4 output/PWM4 output. Analog Input 18. ECCP3 PWM Output D. Comparator 3 Input B. I/O O O I I I/O I O I ST Analog — ST ST ST Analog — Analog Digital I/O. SEG26 output for LCD. RTCC output Timer7 clock input. Timer5 external clock gate input. Capture 5 input/Compare 5 output/PWM5 output. Analog Input 16. ECCP1 PWM Output D. Comparator 3 Input C. Digital I/O. Capture 3 input/Compare 3 output/PWM3 output. ECCP3 PWM Output A. See the MCLR/RG5 pin. Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output ST = Schmitt Trigger input with CMOS levels Analog = Analog input I = Input O = Output P = Power OD = Open-Drain (no P diode to VDD) I2C™ = I2C/SMBus Note 1: Default assignment for ECCP2 when the CCP2MX Configuration bit is set. 2: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared. 3: Not available on PIC18F65K90 and PIC18F85K90 devices. 2010 Microchip Technology Inc. Preliminary DS39957B-page 21 PIC18F87K90 FAMILY TABLE 1-3: PIC18F6XK90 PINOUT I/O DESCRIPTIONS (CONTINUED) Pin Name Pin Number QFN/TQFP Pin Buffer Type Type Description VSS 9, 25, 41, 56 P — VDD 26, 38, 57 P — Ground reference for logic and I/O pins. Positive supply for logic and I/O pins. AVSS 20 P — Ground reference for analog modules. AVDD 19 P — Positive supply for analog modules. ENVREG 18 I ST Enable for on-chip voltage regulator. VDDCORE/VCAP VDDCORE VCAP 10 Core logic power or external filter capacitor connection. P — External filter capacitor connection (regulator enabled/disabled). Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output ST = Schmitt Trigger input with CMOS levels Analog = Analog input I = Input O = Output P = Power OD = Open-Drain (no P diode to VDD) I2C™ = I2C/SMBus Note 1: Default assignment for ECCP2 when the CCP2MX Configuration bit is set. 2: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared. 3: Not available on PIC18F65K90 and PIC18F85K90 devices. TABLE 1-4: PIC18F8XK90 PINOUT I/O DESCRIPTIONS Pin Name MCLR/RG5 Pin Number TQFP Pin Buffer Type Type 9 I ST I ST I I CMOS CMOS I/O TTL O — CLKO O — RA6 I/O TTL RG5 OSC1/CLKI/RA7 OSC1 CLKI 49 RA7 OSC2/CLKO/RA6 OSC2 Description 50 Master Clear (input) or programming voltage (input). This pin is an active-low Reset to the device. General purpose, input only pin. Oscillator crystal or external clock input. Oscillator crystal input. External clock source input. Always associated with pin function, OSC1. (See related OSC1/CLKI, OSC2/CLKO pins.) General purpose I/O pin. Oscillator crystal or clock output. Oscillator crystal output. Connects to crystal or resonator in Crystal Oscillator mode. In certain oscillator modes, OSC2 pin outputs CLKO, which has 1/4 the frequency of OSC1 and denotes the instruction cycle rate. General purpose I/O pin. Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output ST = Schmitt Trigger input with CMOS levels Analog = Analog input I = Input O = Output P = Power OD = Open-Drain (no P diode to VDD) I2C™ = I2C/SMBus Note 1: Default assignment for ECCP2 when the CCP2MX Configuration bit is set. 2: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared. 3: Not available on PIC18F65K90 and PIC18F85K90 devices. 4: The CCP6, CCP7, CCP8 and CCP9 pin placement depends on the ECCPMX Configuration bit setting. DS39957B-page 22 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY TABLE 1-4: PIC18F8XK90 PINOUT I/O DESCRIPTIONS (CONTINUED) Pin Name Pin Number TQFP Pin Buffer Type Type Description PORTA is a bidirectional I/O port. RA0/AN0/ULPWU RA0 AN0 ULPWU 30 RA1/AN1/SEG18 RA1 AN1 SEG18 29 RA2/AN2/VREFRA2 AN2 VREF- 28 RA3/AN3/VREF+ RA3 AN3 VREF+ 27 RA4/T0CKI/SEG14 RA4 T0CKI SEG14 34 RA5/AN4/SEG15/T1CKI/ T3G/HLVDIN RA5 AN4 SEG15 T1CKI T3G HLVDIN 33 I/O I I TTL Analog Analog Digital I/O. Analog Input 0. Ultra low-power wake-up input. I/O I O TTL Analog Analog Digital I/O. Analog Input 1. SEG18 output for LCD. I/O I I TTL Analog Analog Digital I/O. Analog Input 2. A/D reference voltage (low) input. I/O I I TTL Analog Analog Digital I/O. Analog Input 3. A/D reference voltage (high) input. I/O I O ST ST Analog Digital I/O. Timer0 external clock input. SEG14 output for LCD. I/O I O I I I TTL Analog Analog ST ST Analog Digital I/O. Analog Input 4. SEG15 output for LCD. Timer1 clock input. Timer3 external clock gate input. High/Low-Voltage Detect (HLVD) input. RA6 See the OSC2/CLKO/RA6 pin. RA7 See the OSC1/CLKI/RA7 pin. Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output ST = Schmitt Trigger input with CMOS levels Analog = Analog input I = Input O = Output P = Power OD = Open-Drain (no P diode to VDD) I2C™ = I2C/SMBus Note 1: Default assignment for ECCP2 when the CCP2MX Configuration bit is set. 2: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared. 3: Not available on PIC18F65K90 and PIC18F85K90 devices. 4: The CCP6, CCP7, CCP8 and CCP9 pin placement depends on the ECCPMX Configuration bit setting. 2010 Microchip Technology Inc. Preliminary DS39957B-page 23 PIC18F87K90 FAMILY TABLE 1-4: PIC18F8XK90 PINOUT I/O DESCRIPTIONS (CONTINUED) Pin Name Pin Number TQFP Pin Buffer Type Type Description PORTB is a bidirectional I/O port. PORTB can be software programmed for internal weak pull-ups on all inputs. RB0/INT0/SEG30/FLT0 RB0 INT0 SEG30 FLT0 58 RB1/INT1/SEG8 RB1 INT1 SEG8 57 RB2/INT2/SEG9/CTED1 RB2 INT2 SEG9 CTED1 56 RB3/INT3/SEG10/ CTED2/ECCP2/P2A RB3 INT3 SEG10 CTED2 ECCP2 P2A 55 RB4/KBI0/SEG11 RB4 KBI0 SEG11 54 RB5/KBI1/SEG29/T3CKI/ T1G RB5 KBI1 SEG29 T3CKI T1G 53 I/O I O I TTL ST Analog ST Digital I/O. External Interrupt 0. SEG30 output for LCD. Enhanced PWM Fault input for ECCP1/2/3. I/O I O TTL ST Analog Digital I/O. External Interrupt 1. SEG8 output for LCD. I/O I O I TTL ST Analog ST Digital I/O. External Interrupt 2. SEG9 output for LCD. CTMU Edge 1 input. I/O I O I I/O O TTL ST Analog ST ST ST Digital I/O. External Interrupt 3. SEG10 output for LCD. CTMU Edge 2 input. Capture 2 input/Compare 2 output/PWM2 output. Enhanced PWM 2 Output A. I/O I O TTL TTL Analog Digital I/O. Interrupt-on-change pin. SEG11 output for LCD. I/O I O I I TTL TTL Analog ST ST Digital I/O. Interrupt-on-change pin. SEG29 output for LCD. Timer3 clock input. Timer1 external clock gate input. Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output ST = Schmitt Trigger input with CMOS levels Analog = Analog input I = Input O = Output P = Power OD = Open-Drain (no P diode to VDD) I2C™ = I2C/SMBus Note 1: Default assignment for ECCP2 when the CCP2MX Configuration bit is set. 2: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared. 3: Not available on PIC18F65K90 and PIC18F85K90 devices. 4: The CCP6, CCP7, CCP8 and CCP9 pin placement depends on the ECCPMX Configuration bit setting. DS39957B-page 24 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY TABLE 1-4: PIC18F8XK90 PINOUT I/O DESCRIPTIONS (CONTINUED) Pin Name Pin Number TQFP RB6/KBI2/PGC RB6 KBI2 PGC 52 RB7/KBI3/PGD RB7 KBI3 PGD 47 Pin Buffer Type Type Description I/O I I/O TTL TTL ST Digital I/O. Interrupt-on-change pin. In-Circuit Debugger and ICSP™ programming clock pin. I/O I I/O TTL TTL ST Digital I/O. Interrupt-on-change pin. In-Circuit Debugger and ICSP programming data pin. Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output ST = Schmitt Trigger input with CMOS levels Analog = Analog input I = Input O = Output P = Power OD = Open-Drain (no P diode to VDD) I2C™ = I2C/SMBus Note 1: Default assignment for ECCP2 when the CCP2MX Configuration bit is set. 2: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared. 3: Not available on PIC18F65K90 and PIC18F85K90 devices. 4: The CCP6, CCP7, CCP8 and CCP9 pin placement depends on the ECCPMX Configuration bit setting. 2010 Microchip Technology Inc. Preliminary DS39957B-page 25 PIC18F87K90 FAMILY TABLE 1-4: PIC18F8XK90 PINOUT I/O DESCRIPTIONS (CONTINUED) Pin Name Pin Number TQFP Pin Buffer Type Type Description PORTC is a bidirectional I/O port. RC0/SOSCO/SCKLI RC0 SOSCO SCKLI 36 RC1/SOSCI/ECCP2/ SEG32/P2A RC1 SOSCI ECCP2(1) SEG32 P2A 35 RC2/ECCP1/P1A/SEG13 RC2 ECCP1 P1A SEG13 43 RC3/SCK1/SCL1/SEG17 RC3 SCK1 SCL1 SEG17 44 RC4/SDI1/SDA1/SEG16 RC4 SDI1 SDA1 SEG16 45 RC5/SDO1/SEG12 RC5 SDO1 SEG12 46 RC6/TX1/CK1/SEG27 RC6 TX1 CK1 SEG27 37 RC7/RX1/DT1/SEG28 RC7 RX1 DT1 SEG28 38 I/O O I ST — ST I/O I I/O O O ST CMOS ST Analog — Digital I/O. SOSC oscillator input. Capture 2 input/Compare 2 output/PWM2 output. SEG32 output for LCD. Enhanced PWM 2 Output A. I/O I/O O O ST ST — Analog Digital I/O. Capture 1 input/Compare 1 output/PWM1 output. Enhanced PWM 1 Output A. SEG13 output for LCD. I/O I/O I/O O ST ST ST Analog Digital I/O. Synchronous serial clock input/output for SPI mode. Synchronous serial clock input/output for I2C™ mode. SEG17 output for LCD. I/O I I/O O ST ST ST Analog Digital I/O. SPI data in. I2C data I/O. SEG16 output for LCD. I/O O O ST — Analog Digital I/O. SPI data out. SEG12 output for LCD. I/O O I/O O ST — ST Analog Digital I/O. EUSART asynchronous transmit. EUSART synchronous clock (see related RX1/DT1). SEG27 output for LCD. I/O I I/O O ST ST ST Analog Digital I/O. EUSART asynchronous receive. EUSART synchronous data (see related TX1/CK1). SEG28 output for LCD. Digital I/O. SOSC oscillator output. Digital SOSC input. Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output ST = Schmitt Trigger input with CMOS levels Analog = Analog input I = Input O = Output P = Power OD = Open-Drain (no P diode to VDD) I2C™ = I2C/SMBus Note 1: Default assignment for ECCP2 when the CCP2MX Configuration bit is set. 2: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared. 3: Not available on PIC18F65K90 and PIC18F85K90 devices. 4: The CCP6, CCP7, CCP8 and CCP9 pin placement depends on the ECCPMX Configuration bit setting. DS39957B-page 26 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY TABLE 1-4: PIC18F8XK90 PINOUT I/O DESCRIPTIONS (CONTINUED) Pin Name Pin Number TQFP Pin Buffer Type Type Description PORTD is a bidirectional I/O port. RD0/SEG0/CTPLS RD0 SEG0 CTPLS 72 RD1/SEG1/T5CKI/T7G RD1 SEG1 T5CKI T7G 69 RD2/SEG2 RD2 SEG2 68 RD3/SEG3 RD3 SEG3 67 RD4/SEG4/SDO2 RD4 SEG4 SDO2 66 RD5/SEG5/SDI2/SDA2 RD5 SEG5 SDI2 SDA2 65 RD6/SEG6/SCK2/SCL2 RD6 SEG6 SCK2 SCL2 64 RD7/SEG7/SS2 RD7 SEG7 SS2 63 I/O O O ST Analog ST Digital I/O. SEG0 output for LCD. CTMU pulse generator output. I/O O I I ST Analog ST ST Digital I/O. SEG1 output for LCD. Timer5 clock input. Timer7 external clock gate input. I/O O ST Analog Digital I/O. SEG2 output for LCD. I/O O ST Analog Digital I/O. SEG3 output for LCD. I/O O O ST Analog — Digital I/O. SEG4 output for LCD. SPI data out. I/O O I I/O ST Analog ST I2C Digital I/O. SEG5 output for LCD. SPI data in. I2C™ data in. I/O O I/O I/O ST Analog ST I2C Digital I/O. SEG6 output for LCD. Synchronous serial clock input/output for SPI mode. Synchronous serial clock input/output for I2C™ mode. I/O O I ST Analog TTL Digital I/O. SEG7 output for LCD. SPI slave select input. Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output ST = Schmitt Trigger input with CMOS levels Analog = Analog input I = Input O = Output P = Power OD = Open-Drain (no P diode to VDD) I2C™ = I2C/SMBus Note 1: Default assignment for ECCP2 when the CCP2MX Configuration bit is set. 2: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared. 3: Not available on PIC18F65K90 and PIC18F85K90 devices. 4: The CCP6, CCP7, CCP8 and CCP9 pin placement depends on the ECCPMX Configuration bit setting. 2010 Microchip Technology Inc. Preliminary DS39957B-page 27 PIC18F87K90 FAMILY TABLE 1-4: PIC18F8XK90 PINOUT I/O DESCRIPTIONS (CONTINUED) Pin Name Pin Number TQFP Pin Buffer Type Type Description PORTE is a bidirectional I/O port. RE0/LCDBIAS1/P2D RE0 LCDBIAS1 P2D 4 RE1/LCDBIAS2/P2C RE1 LCDBIAS2 P2C 3 RE2/LCDBIAS3/P2B/ CCP10 RE2 LCDBIAS3 P2B CCP10(3) 78 RE3/COM0/P3C/CCP9/ REFO RE3 COM0 P3C CCP9(4) REFO 77 RE4/COM1/P3B/CCP8 RE4 COM1 P3B CCP8(4) 76 RE5/COM2/P1C/CCP7 RE5 COM2 P1C CCP7(4) 75 RE6/COM3/P1B/CCP6 RE6 COM3 P1B CCP6(4) 74 RE7/ECCP2/P2A/SEG31 RE7 ECCP2(2) P2A SEG31 73 I/O I O ST Analog — Digital I/O. BIAS1 input for LCD. ECCP2 PWM Output D. I/O I O ST Analog — Digital I/O. BIAS2 input for LCD. ECCP2 PWM Output C. I/O I O I/O ST Analog ST ST Digital I/O. BIAS3 input for LCD. ECCP2 PWM Output B. Capture 10 input/Compare 10 output/PWM10 output. I/O O O I/O O ST Analog — S/T — Digital I/O. COM0 output for LCD. ECCP3 PWM Output C. Capture 9 input/Compare 9 output/PWM9 output. Reference clock out. I/O O O I/O ST Analog — ST Digital I/O. COM1 output for LCD. ECCP4 PWM Output B. Capture 8 input/Compare 8 output/PWM8 output. I/O O O I/O ST Analog — ST Digital I/O. COM2 output for LCD. ECCP1 PWM Output C. Capture 7 input/Compare 7 output/PWM7 output. I/O O O I/O ST Analog — ST Digital I/O. COM3 output for LCD. ECCP1 PWM Output B. Capture 6 input/Compare 6 output/PWM6 output. I/O I/O O O ST ST — Analog Digital I/O. Capture 2 input/Compare 2 output/PWM2 output. ECCP2 PWM Output A. SEG31 output for LCD. Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output ST = Schmitt Trigger input with CMOS levels Analog = Analog input I = Input O = Output P = Power OD = Open-Drain (no P diode to VDD) I2C™ = I2C/SMBus Note 1: Default assignment for ECCP2 when the CCP2MX Configuration bit is set. 2: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared. 3: Not available on PIC18F65K90 and PIC18F85K90 devices. 4: The CCP6, CCP7, CCP8 and CCP9 pin placement depends on the ECCPMX Configuration bit setting. DS39957B-page 28 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY TABLE 1-4: PIC18F8XK90 PINOUT I/O DESCRIPTIONS (CONTINUED) Pin Name Pin Number TQFP Pin Buffer Type Type Description PORTF is a bidirectional I/O port. RF1/AN6/C2OUT/SEG19/ CTDIN RF1 AN6 C2OUT SEG19 CTDIN 23 RF2/AN7/C1OUT/ SEG20/CTMUI RF2 AN7 C1OUT SEG20 CTMUI 18 RF3/AN8/SEG21/C2INB RF3 AN8 SEG21 C2INB 17 RF4/AN9/SEG22/C2INA RF4 AN9 SEG22 C2INA 16 RF5/AN10/CVREF/ SEG23/C1INB RF5 AN10 CVREF SEG23 C1INB 15 RF6/AN11/SEG24/C1INA RF6 AN11 SEG24 C1INA 14 RF7/AN5/SS1/SEG25 RF7 AN5 SS1 SEG25 13 I/O I O O I ST Analog — Analog ST Digital I/O. Analog Input 6. Comparator 2 output. SEG19 output for LCD. CTMU pulse delay input. I/O I O O O ST Analog — Analog — Digital I/O. Analog Input 7. Comparator 1 output. SEG20 output for LCD. CTMU pulse generator charger for the C2INB comparator input. I/O I O I ST Analog Analog Analog Digital I/O. Analog Input 8. SEG21 output for LCD. Comparator 2 Input B. I/O I O I ST Analog Analog Analog Digital I/O. Analog Input 9. SEG22 output for LCD. Comparator 2 Input A. I/O I O O I ST Analog Analog Analog Analog Digital I/O. Analog Input 10. Comparator reference voltage output. SEG23 output for LCD. Comparator 1 Input B. I/O I O I ST Analog Analog Analog Digital I/O. Analog Input 11. SEG24 output for LCD. Comparator 1 Input A. I/O O I O ST Analog TTL Analog Digital I/O. Analog Input 5. SPI slave select input. SEG25 output for LCD. Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output ST = Schmitt Trigger input with CMOS levels Analog = Analog input I = Input O = Output P = Power OD = Open-Drain (no P diode to VDD) I2C™ = I2C/SMBus Note 1: Default assignment for ECCP2 when the CCP2MX Configuration bit is set. 2: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared. 3: Not available on PIC18F65K90 and PIC18F85K90 devices. 4: The CCP6, CCP7, CCP8 and CCP9 pin placement depends on the ECCPMX Configuration bit setting. 2010 Microchip Technology Inc. Preliminary DS39957B-page 29 PIC18F87K90 FAMILY TABLE 1-4: PIC18F8XK90 PINOUT I/O DESCRIPTIONS (CONTINUED) Pin Name Pin Number TQFP Pin Buffer Type Type Description PORTG is a bidirectional I/O port. RG0/ECCP3/P3A RG0 ECCP3 P3A 5 RG1/TX2/CK2/AN19/ C3OUT RG1 TX2 CK2 AN19 C3OUT 6 RG2/RX2/DT2/AN18/ C3INA RG2 RX2 DT2 AN18 C3INA 7 RG3/CCP4/AN17/P3D/ C3INB RG3 CCP4 AN17 P3D C3INB 8 RG4/SEG26/RTCC/ T7CKI/T5G/CCP5/AN16/ P1D/C3INC RG4 SEG26 RTCC T7CKI(3) T5G CCP5 AN16 P1D C3INC 10 RG5 9 I/O I/O O ST ST — I/O O I/O I O ST — ST Analog — Digital I/O. EUSART asynchronous transmit. EUSART synchronous clock (see related RX2/DT2). Analog Input 19. Comparator 3 output. I/O I I/O I I ST ST ST Analog Analog Digital I/O. EUSART asynchronous receive. EUSART synchronous data (see related TX2/CK2). Analog Input 18. Comparator 3 Input A. I/O I/O I O I ST ST Analog — Analog Digital I/O. Capture 4 input/Compare 4 output/PWM4 output. Analog Input 17. ECCP3 PWM Output D. Comparator 3 Input B. I/O O O I I I/O I O I ST Analog — ST ST ST Analog — Analog Digital I/O. SEG26 output for LCD. RTCC output. Timer7 clock input. Timer5 external clock gate input. Capture 5 input/Compare 5 output/PWM5 output. Analog Input 16. ECCP1 PWM Output D. Comparator 3 Input C. Digital I/O. Capture 3 input/Compare 3 output/PWM3 output. ECCP3 PWM Output A. See the MCLR/RG5 pin. Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output ST = Schmitt Trigger input with CMOS levels Analog = Analog input I = Input O = Output P = Power OD = Open-Drain (no P diode to VDD) I2C™ = I2C/SMBus Note 1: Default assignment for ECCP2 when the CCP2MX Configuration bit is set. 2: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared. 3: Not available on PIC18F65K90 and PIC18F85K90 devices. 4: The CCP6, CCP7, CCP8 and CCP9 pin placement depends on the ECCPMX Configuration bit setting. DS39957B-page 30 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY TABLE 1-4: PIC18F8XK90 PINOUT I/O DESCRIPTIONS (CONTINUED) Pin Name Pin Number TQFP Pin Buffer Type Type Description PORTH is a bidirectional I/O port. RH0/SEG47/AN23 RH0 SEG47 AN23 79 RH1/SEG46/AN22 RH1 SEG46 AN22 80 RH2/SEG45/AN21 RH2 SEG45 AN21 1 RH3/SEG44/AN20 RH3 SEG44 AN20 2 RH4/SEG40/CCP9/P3C/ AN12/C2INC RH4 SEG40 CCP9(4) P3C AN12 C2INC 22 RH5/SEG41/CCP8/P3B/ AN13/C2IND RH5 SEG41 CCP8(4) P3B AN13 C2IND 21 RH6/SEG42/CCP7/P1C/ AN14/C1INC RH6 SEG42 CCP7(4) P1C AN14 C1INC 20 I/O O I ST Analog Analog Digital I/O. SEG47 output for LCD. Analog Input 23. I/O O I ST Analog Analog Digital I/O. SEG46 output for LCD. Analog Input 22. I/O O I ST Analog Analog Digital I/O. SEG45 output for LCD. Analog Input 21. I/O O I ST Analog Analog Digital I/O. SEG44 output for LCD. Analog Input 20. I/O O I/O O I I ST Analog ST — Analog Analog Digital I/O. SEG40 output for LCD. Capture 9 input/Compare 9 output/PWM9 output. ECCP3 PWM Output C. Analog Input 12. Comparator 2 Input C. I/O O I/O O I I ST Analog ST — Analog Analog Digital I/O. SEG41 output for LCD. Capture 8 input/Compare 8 output/PWM8 output. ECCP3 PWM Output B. Analog Input 13. Comparator 1 Input D. I/O O I/O O I I ST Analog ST — Analog Analog Digital I/O. SEG42 output for LCD. Capture 7 input/Compare 7 output/PWM7 output. ECCP1 PWM Output C. Analog Input 14. Comparator 1 Input C. Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output ST = Schmitt Trigger input with CMOS levels Analog = Analog input I = Input O = Output P = Power OD = Open-Drain (no P diode to VDD) I2C™ = I2C/SMBus Note 1: Default assignment for ECCP2 when the CCP2MX Configuration bit is set. 2: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared. 3: Not available on PIC18F65K90 and PIC18F85K90 devices. 4: The CCP6, CCP7, CCP8 and CCP9 pin placement depends on the ECCPMX Configuration bit setting. 2010 Microchip Technology Inc. Preliminary DS39957B-page 31 PIC18F87K90 FAMILY TABLE 1-4: PIC18F8XK90 PINOUT I/O DESCRIPTIONS (CONTINUED) Pin Name RH7/SEG43/CCP6/P1B/ AN15 RH7 SEG43 CCP6(4) P1B AN15 Pin Number TQFP Pin Buffer Type Type Description 19 I/O O I/O O I ST Analog ST — Analog Digital I/O. SEG43 output for LCD. Capture 6 input/Compare 6 output/PWM6 output. ECCP1 PWM Output B. Analog Input 15. Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output ST = Schmitt Trigger input with CMOS levels Analog = Analog input I = Input O = Output P = Power OD = Open-Drain (no P diode to VDD) I2C™ = I2C/SMBus Note 1: Default assignment for ECCP2 when the CCP2MX Configuration bit is set. 2: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared. 3: Not available on PIC18F65K90 and PIC18F85K90 devices. 4: The CCP6, CCP7, CCP8 and CCP9 pin placement depends on the ECCPMX Configuration bit setting. DS39957B-page 32 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY TABLE 1-4: PIC18F8XK90 PINOUT I/O DESCRIPTIONS (CONTINUED) Pin Name Pin Number TQFP Pin Buffer Type Type Description PORTJ is a bidirectional I/O port. RJ0 62 RJ1/SEG33 RJ1 SEG33 61 RJ2/SEG34 RJ2 SEG34 60 RJ3/SEG35 RJ3 SEG35 59 RJ4/SEG39 RJ4 SEG39 39 RJ5/SEG38 RJ5 SEG38 40 RJ6/SEG37 RJ6 SEG37 41 RJ7/SEG36 RJ7 SEG36 42 I/O ST Digital I/O. I/O O ST Analog Digital I/O. SEG33 output for LCD. I/O O ST Analog Digital I/O. SEG34 output for LCD. I/O O ST Analog Digital I/O. SEG35 output for LCD. I/O O ST Analog Digital I/O. SEG39 output for LCD. I/O O ST Analog Digital I/O SEG38 output for LCD. I/O O ST Analog Digital I/O. SEG37 output for LCD. I/O O ST Analog Digital I/O. SEG36 output for LCD. VSS 11, 31, 51, 70 P — Ground reference for logic and I/O pins. VDD 32, 48, 71 P — Positive supply for logic and I/O pins. AVSS 26 P — Ground reference for analog modules. AVDD 25 P — Positive supply for analog modules. ENVREG 24 I ST VDDCORE/VCAP VDDCORE VCAP 12 Enable for on-chip voltage regulator. Core logic power or external filter capacitor connection. P — External filter capacitor connection (regulator enabled/disabled). Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output ST = Schmitt Trigger input with CMOS levels Analog = Analog input I = Input O = Output P = Power OD = Open-Drain (no P diode to VDD) I2C™ = I2C/SMBus Note 1: Default assignment for ECCP2 when the CCP2MX Configuration bit is set. 2: Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared. 3: Not available on PIC18F65K90 and PIC18F85K90 devices. 4: The CCP6, CCP7, CCP8 and CCP9 pin placement depends on the ECCPMX Configuration bit setting. 2010 Microchip Technology Inc. Preliminary DS39957B-page 33 PIC18F87K90 FAMILY NOTES: DS39957B-page 34 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY RECOMMENDED MINIMUM CONNECTIONS C2(2) VDD R1 R2 VCAP/VDDCORE C1 C7(2) PIC18FXXKXX VSS VDD VDD VSS C3(2) C5(2) VSS C6(2) VDD • All VDD and VSS pins (see Section 2.2 “Power Supply Pins”) • All AVDD and AVSS pins, regardless of whether or not the analog device features are used (see Section 2.2 “Power Supply Pins”) • MCLR pin (see Section 2.3 “Master Clear (MCLR) Pin”) • ENVREG (if implemented) and VCAP/VDDCORE pins (see Section 2.4 “Voltage Regulator Pins (ENVREG and VCAP/VDDCORE)”) (1) (1) ENVREG MCLR The following pins must always be connected: C4(2) Key (all values are recommendations): These pins must also be connected if they are being used in the end application: C1 through C6: 0.1 F, 20V ceramic • PGC/PGD pins used for In-Circuit Serial Programming™ (ICSP™) and debugging purposes (see Section 2.5 “ICSP Pins”) • OSCI and OSCO pins when an external oscillator source is used (see Section 2.6 “External Oscillator Pins”) R2: 100Ω to 470Ω R1: 10 kΩ Note 1: Additionally, the following pins may be required: • VREF+/VREF- pins are used when external voltage reference for analog modules is implemented Note: VSS Getting started with the PIC18F87K90 family family of 8-bit microcontrollers requires attention to a minimal set of device pin connections before proceeding with development. VDD Basic Connection Requirements FIGURE 2-1: AVSS 2.1 GUIDELINES FOR GETTING STARTED WITH PIC18FXXKXX MICROCONTROLLERS AVDD 2.0 2: See Section 2.4 “Voltage Regulator Pins (ENVREG and VCAP/VDDCORE)” for explanation of ENVREG pin connections. The example shown is for a PIC18F device with five VDD/VSS and AVDD/AVSS pairs. Other devices may have more or less pairs; adjust the number of decoupling capacitors appropriately. The AVDD and AVSS pins must always be connected, regardless of whether any of the analog modules are being used. The minimum mandatory connections are shown in Figure 2-1. 2010 Microchip Technology Inc. Preliminary DS39957B-page 35 PIC18F87K90 FAMILY 2.2 2.2.1 Power Supply Pins 2.3 DECOUPLING CAPACITORS The use of decoupling capacitors on every pair of power supply pins, such as VDD, VSS, AVDD and AVSS, is required. Consider the following criteria when using decoupling capacitors: • Value and type of capacitor: A 0.1 F (100 nF), 10-20V capacitor is recommended. The capacitor should be a low-ESR device, with a resonance frequency in the range of 200 MHz and higher. Ceramic capacitors are recommended. • Placement on the printed circuit board: The decoupling capacitors should be placed as close to the pins as possible. It is recommended to place the capacitors on the same side of the board as the device. If space is constricted, the capacitor can be placed on another layer on the PCB using a via; however, ensure that the trace length from the pin to the capacitor is no greater than 0.25 inch (6 mm). • Handling high-frequency noise: If the board is experiencing high-frequency noise (upward of tens of MHz), add a second ceramic type capacitor in parallel to the above described decoupling capacitor. The value of the second capacitor can be in the range of 0.01 F to 0.001 F. Place this second capacitor next to each primary decoupling capacitor. In high-speed circuit designs, consider implementing a decade pair of capacitances as close to the power and ground pins as possible (e.g., 0.1 F in parallel with 0.001 F). • Maximizing performance: On the board layout from the power supply circuit, run the power and return traces to the decoupling capacitors first, and then to the device pins. This ensures that the decoupling capacitors are first in the power chain. Equally important is to keep the trace length between the capacitor and the power pins to a minimum, thereby reducing PCB trace inductance. 2.2.2 TANK CAPACITORS The MCLR pin provides two specific device functions: Device Reset, and Device Programming and Debugging. If programming and debugging are not required in the end application, a direct connection to VDD may be all that is required. The addition of other components, to help increase the application’s resistance to spurious Resets from voltage sags, may be beneficial. A typical configuration is shown in Figure 2-1. Other circuit designs may be implemented, depending on the application’s requirements. During programming and debugging, the resistance and capacitance that can be added to the pin must be considered. Device programmers and debuggers drive the MCLR pin. Consequently, specific voltage levels (VIH and VIL) and fast signal transitions must not be adversely affected. Therefore, specific values of R1 and C1 will need to be adjusted based on the application and PCB requirements. For example, it is recommended that the capacitor, C1, be isolated from the MCLR pin during programming and debugging operations by using a jumper (Figure 2-2). The jumper is replaced for normal run-time operations. Any components associated with the MCLR pin should be placed within 0.25 inch (6 mm) of the pin. FIGURE 2-2: EXAMPLE OF MCLR PIN CONNECTIONS VDD R1 R2 JP MCLR PIC18FXXKXX C1 Note 1: R1 10 k is recommended. A suggested starting value is 10 k. Ensure that the MCLR pin VIH and VIL specifications are met. 2: R2 470 will limit any current flowing into MCLR from the external capacitor, C, in the event of MCLR pin breakdown, due to Electrostatic Discharge (ESD) or Electrical Overstress (EOS). Ensure that the MCLR pin VIH and VIL specifications are met. On boards with power traces running longer than six inches in length, it is suggested to use a tank capacitor for integrated circuits, including microcontrollers, to supply a local power source. The value of the tank capacitor should be determined based on the trace resistance that connects the power supply source to the device, and the maximum current drawn by the device in the application. In other words, select the tank capacitor so that it meets the acceptable voltage sag at the device. Typical values range from 4.7 F to 47 F. DS39957B-page 36 Master Clear (MCLR) Pin Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY Voltage Regulator Pins (ENVREG and VCAP/VDDCORE) The on-chip voltage regulator enable pin, ENVREG, must always be connected directly to either a supply voltage or to ground. Tying ENVREG to VDD enables the regulator, while tying it to ground disables the regulator. Refer to Section 28.3 “On-Chip Voltage Regulator” for details on connecting and using the on-chip regulator. When the regulator is enabled, a low-ESR (< 5Ω) capacitor is required on the VCAP/VDDCORE pin to stabilize the voltage regulator output voltage. The VCAP/VDDCORE pin must not be connected to VDD and must use a capacitor of 10 F connected to ground. The type can be ceramic or tantalum. A suitable example is the Murata GRM21BF50J106ZE01 (10 F, 6.3V) or equivalent. Designers may use Figure 2-3 to evaluate ESR equivalence of candidate devices. It is recommended that the trace length not exceed 0.25 inch (6 mm). Refer to Section 31.0 “Electrical Characteristics” for additional information. When the regulator is disabled, a 0.1 F capacitor should be connected from the VCAP/VDDCORE pin to ground. This capacitor’s characteristics must be similar to those of the “decoupling” capacitors explained in Section 2.2.1 “Decoupling Capacitors”. For details on the VDD requirement, when the regulator is disabled, see parameter D001 in Section 31.0 “Electrical Characteristics”. Some PIC18FXXKXX families or some devices within a family do not provide the option of enabling or disabling the on-chip voltage regulator: • Some devices (with the name, PIC18LFXXKXX) permanently disable the voltage regulator. These devices’ do not have the ENVREG pin and require a 0.1 F capacitor on the VCAP/VDDCORE pin. The VDD level of these devices must comply with the “voltage regulator disabled” specification for parameter D001, in Section 31.0 “Electrical Characteristics”. • Some devices permanently enable the voltage regulator. These devices also do not have the ENVREG pin. The 10F capacitor is still required on the VCAP/VDDCORE pin. FIGURE 2-3: FREQUENCY vs. ESR PERFORMANCE FOR SUGGESTED VCAP 10 1 ESR () 2.4 0.1 0.01 0.001 0.01 Note: 2.5 0.1 1 10 100 Frequency (MHz) 1000 10,000 Data for Murata GRM21BF50J106ZE01 shown. Measurements at 25°C, 0V DC bias. ICSP Pins The PGC and PGD pins are used for In-Circuit Serial Programming™ (ICSP™) and debugging purposes. It is recommended to keep the trace length between the ICSP connector and the ICSP pins on the device as short as possible. If the ICSP connector is expected to experience an ESD event, a series resistor is recommended, with the value in the range of a few tens of ohms, not to exceed 100Ω. Pull-up resistors, series diodes and capacitors on the PGC and PGD pins are not recommended as they will interfere with the programmer/debugger communications to the device. If such discrete components are an application requirement, they should be removed from the circuit during programming and debugging. Alternatively, refer to the AC/DC characteristics and timing requirements information in the respective device Flash programming specification for information on capacitive loading limits, and pin input voltage high (VIH) and input low (VIL) requirements. For device emulation, ensure that the “Communication Channel Select” (i.e., PGCx/PGDx pins) programmed into the device matches the physical connections for the ICSP to the Microchip debugger/emulator tool. For more information on available Microchip development tools connection requirements, refer to Section 30.0 “Development Support”. For details on all members of the PIC18F87K90 family, see Section 28.3 “On-Chip Voltage Regulator”. 2010 Microchip Technology Inc. Preliminary DS39957B-page 37 PIC18F87K90 FAMILY 2.6 External Oscillator Pins FIGURE 2-4: Many microcontrollers have options for at least two oscillators: a high-frequency primary oscillator and a low-frequency secondary oscillator (refer to Section 3.0 “Oscillator Configurations” for details). Single-Sided and In-Line Layouts: Copper Pour (tied to ground) The oscillator circuit should be placed on the same side of the board as the device. Place the oscillator circuit close to the respective oscillator pins with no more than 0.5 inch (12 mm) between the circuit components and the pins. The load capacitors should be placed next to the oscillator itself, on the same side of the board. Use a grounded copper pour around the oscillator circuit to isolate it from surrounding circuits. The grounded copper pour should be routed directly to the MCU ground. Do not run any signal traces or power traces inside the ground pour. Also, if using a two-sided board, avoid any traces on the other side of the board where the crystal is placed. Primary Oscillator OSC1 C1 ` OSC2 GND C2 ` T1OSO T1OS I Timer1 Oscillator Crystal ` T1 Oscillator: C1 T1 Oscillator: C2 Fine-Pitch (Dual-Sided) Layouts: Top Layer Copper Pour (tied to ground) Bottom Layer Copper Pour (tied to ground) For additional information and design guidance on oscillator circuits, please refer to these Microchip Application Notes, available at the corporate web site (www.microchip.com): • AN826, “Crystal Oscillator Basics and Crystal Selection for rfPIC™ and PICmicro® Devices” • AN849, “Basic PICmicro® Oscillator Design” • AN943, “Practical PICmicro® Oscillator Analysis and Design” • AN949, “Making Your Oscillator Work” 2.7 Primary Oscillator Crystal DEVICE PINS Layout suggestions are shown in Figure 2-4. In-line packages may be handled with a single-sided layout that completely encompasses the oscillator pins. With fine-pitch packages, it is not always possible to completely surround the pins and components. A suitable solution is to tie the broken guard sections to a mirrored ground layer. In all cases, the guard trace(s) must be returned to ground. In planning the application’s routing and I/O assignments, ensure that adjacent port pins and other signals in close proximity to the oscillator are benign (i.e., free of high frequencies, short rise and fall times, and other similar noise). SUGGESTED PLACEMENT OF THE OSCILLATOR CIRCUIT OSCO C2 Oscillator Crystal GND C1 OSCI Unused I/Os DEVICE PINS Unused I/O pins should be configured as outputs and driven to a logic low state. Alternatively, connect a 1 kΩ to 10 kΩ resistor to VSS on unused pins and drive the output to logic low. DS39957B-page 38 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 3.0 OSCILLATOR CONFIGURATIONS 3.1 Oscillator Types To optimize power consumption when using EC/HS/ XT/LP/RC as the primary oscillator, the frequency input range can be configured to yield an optimized power bias: The PIC18F87K90 family of devices can be operated in the following oscillator modes: • EC • ECIO • • • • HS XT LP RC • RCIO • INTIO2 • INTIO1 External Clock, RA6 available External Clock, Clock Out RA6 (FOSC/4 on RA6) High-Speed Crystal/Resonator Crystal/Resonator Low-Power Crystal External Resistor/Capacitor, RA6 available External Resistor/Capacitor, Clock Out RA6 (FOSC/4 on RA6) Internal Oscillator with I/O on RA6 and RA7 Internal Oscillator with FOSC/4 Output on RA6 and I/O on RA7 There is also an option for running the 4xPLL on any of the clock sources in the input frequency range of 4 to 16 MHz. • Low-Power Bias – External frequency less than 160 kHz • Medium Power Bias – External frequency between 160 kHz and 16 MHz • High-Power Bias – External frequency greater than 16 MHz All of these modes are selected by the user by programming the OSC<3:0> Configuration bits (CONFIG1H<3:0>). In addition, PIC18F87K90 family devices can switch between different clock sources, either under software control or under certain conditions, automatically. This allows for additional power savings by managing device clock speed in real time without resetting the application. The clock sources for the PIC18F87K90 family of devices are shown in Figure 3-1. For the HS and EC mode, there are additional power modes of operation – depending on the frequency of operation. For the EC and HS mode, the PLLEN (software) or PLLCFG (CONFIG) bit can be used to enable the PLL. HS1 is the Medium Power mode with a frequency range of 4 MHz to 16 MHz. HS2 is the High-Power mode where the oscillator frequency can go from 16 MHz to 25 MHz. HS1 and HS2 are achieved by setting the CONFIG1H<3:0> correctly. (For details, see Register 28-2 on page 426.) For the INTIOx modes (HF-INTOSC): EC mode has these modes of operation: • Only the PLLEN can enable the PLL (PLLCFG is ignored). • When the oscillator is configured for the internal oscillator (OSC<3:0> = 100x), the PLL can be enabled only when the HF-INTOSC frequency is 8 or 16 MHz. • EC1 – For low power with a frequency range up to 160 kHz • EC2 – Medium power with a frequency range of 160 kHz to 16 MHz • EC3 – High power with a frequency range of 16 MHz to 64 MHz When the RA6 and RA7 pins are not used for an oscillator function or CLKOUT function, they are available as general purpose I/Os. EC1, EC2 and EC3 are achieved by setting the CONFIG1H<3:0> correctly. (For details, see Register 28-2 on page 426.) The PLL is enabled by setting the PLLCFG bit (CONFIG1H<4>) or the PLLEN bit (OSCTUNE<6>). Table 3-1 shows the HS and EC modes’ frequency range and OSC<3:0> settings. 2010 Microchip Technology Inc. Preliminary DS39957B-page 39 PIC18F87K90 FAMILY TABLE 3-1: HS, EC, XT, LP AND RC MODES: RANGES AND SETTINGS Mode Frequency Range EC1 (low power) OSC<3:0> Setting 1101 DC-160 kHz (EC1 & EC1IO) EC2 (medium power) 1100 160 kHz-16 MHz 1011 16 MHz-64 MHz 0101 HS1 (medium power) 4 MHz-16 MHz 0011 HS2 (high power) 16 MHz-25 MHz 0010 XT 100 kHz-4 MHz 0001 LP 31.25 kHz 0000 RC (External) 0-4 MHz 011x INTIO 32 kHz-16 MHz 100x (and OSCCON, OSCCON2) (EC2 & EC2IO) EC3 (high power) (EC3 & EC3IO) FIGURE 3-1: 1010 0100 PIC18F87K90 FAMILY CLOCK DIAGRAM SOSCO SOSCI Peripherals MUX MUX MUX 4x PLL OSC2 CPU OSC1 PLLEN and PLLCFG FOSC<3:0> IDLEN 16 MHz 111 8 MHz 4 MHz 4 MHz 2 MHz 2 MHz 1 MHz 1 MHz 250 kHz 500 kHz DS39957B-page 40 011 FOSC<3:0> IRCF<2:0> MUX 250 kHz 31 kHz MFIOSEL LF INTOSC 31 kHz 100 MUX MF INTOSC 500 kHz to 31 kHz Postscaler 31 kHz SCS<1:0> 101 500 kHz 010 250 kHz 001 31 kHz 000 500 kHz Clock Control 110 MUX HF INTOSC 16 MHz to 31 kHz Postscaler 16 MHz 8 MHz INTSRC 31 kHz Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 3.2 Control Registers The OSCCON register (Register 3-1) controls the main aspects of the device clock’s operation. It selects the oscillator type to be used, which of the power-managed modes to invoke and the output frequency of the INTOSC source. It also provides status on the oscillators. OSCCON: OSCILLATOR CONTROL REGISTER(1) REGISTER 3-1: R/W-0 R/W-1 IDLEN The OSCTUNE register (Register 3-3) controls the tuning and operation of the internal oscillator block. It also implements the PLLEN bit which controls the operation of the Phase Locked Loop (PLL) (see Section 3.5.2 “PLL Frequency Multiplier”). IRCF2 R/W-1 (2) (2) IRCF1 R/W-0 IRCF0 (2) R(1) OSTS R-0 HFIOFS R/W-0 SCS1 (4) R/W-0 SCS0(4) bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 IDLEN: Idle Enable bit 1 = Device enters an Idle mode when a SLEEP instruction is executed 0 = Device enters Sleep mode when a SLEEP instruction is executed bit 6-4 IRCF<2:0>: Internal Oscillator Frequency Select bits(2) 111 = HF-INTOSC output frequency used (16 MHz) 110 = HF-INTOSC/2 output frequency used (8 MHz, default) 101 = HF-INTOSC/4 output frequency used (4 MHz) 100 = HF-INTOSC/8 output frequency used (2 MHz) 011 = HF-INTOSC/16 output frequency used (1 MHz) If INTSRC = 0 and MFIOSEL = 0:(3,5) 010 = HF-INTOSC/32 output frequency used (500 kHz) 001 = HF-INTOSC/64 output frequency used (250 kHz) 000 = LF-INTOSC output frequency used (31.25 kHz) If INTSRC = 1 and MFIOSEL = 0:(3,5) 010 = HF-INTOSC/32 output frequency used (500 kHz) 001 = HF-INTOSC/64 output frequency used (250 kHz) 000 = HF-INTOSC/512 output frequency used (31.25 kHz) If INTSRC = 0 and MFIOSEL = 1:(3,5) 010 = MF-INTOSC output frequency used (500 kHz) 001 = MF-INTOSC/2 output frequency used (250 kHz) 000 = LF-INTOSC output frequency used (31.25 kHz) If INTSRC = 1 and MFIOSEL = 1:(3,5) 010 = MF-INTOSC output frequency used (500 kHz) 001 = MF-INTOSC/2 output frequency used (250 kHz) 000 = MF-INTOSC/16 output frequency used (31.25 kHz) bit 3 OSTS: Oscillator Start-up Timer Time-out Status bit(1) 1 = Oscillator Start-up Timer (OST) time-out has expired: primary oscillator is running, as defined by OSC<3:0> 0 = Oscillator Start-up Timer (OST) time-out is running: primary oscillator is not ready, device is running from an internal oscillator (HF-INTOSC, MF-INTOSC or LF-INTOSC) Note 1: 2: 3: 4: 5: Reset state depends on the state of the IESO Configuration bit (CONFIG1H<7>). Modifying these bits will cause an immediate clock frequency switch if the internal oscillator is providing the device clocks. Source selected by the INTSRC bit (OSCTUNE<7>). Modifying these bits will cause an immediate clock source switch. INTSRC = OSCTUNE<7> and MFIOSEL = OSCCON2<0>. 2010 Microchip Technology Inc. Preliminary DS39957B-page 41 PIC18F87K90 FAMILY REGISTER 3-1: OSCCON: OSCILLATOR CONTROL REGISTER(1) (CONTINUED) bit 2 HFIOFS: INTOSC Frequency Stable bit 1 = HF-INTOSC oscillator frequency is stable 0 = HF-INTOSC oscillator frequency is not stable bit 1-0 SCS<1:0>: System Clock Select bits(4) 1x = Internal oscillator block (LF-INTOSC, MF-INTOSC or HF-INTOSC) 01 = SOSC oscillator 00 = Default primary oscillator (OSC1/OSC2 or HF-INTOSC with or without PLL. Defined by the OSC<3:0> Configuration bits, CONFIG1H<3:0>.) Note 1: 2: 3: 4: 5: Reset state depends on the state of the IESO Configuration bit (CONFIG1H<7>). Modifying these bits will cause an immediate clock frequency switch if the internal oscillator is providing the device clocks. Source selected by the INTSRC bit (OSCTUNE<7>). Modifying these bits will cause an immediate clock source switch. INTSRC = OSCTUNE<7> and MFIOSEL = OSCCON2<0>. REGISTER 3-2: OSCCON2: OSCILLATOR CONTROL REGISTER 2 U-0 R-0 U-0 U-0 R/W-0 U-0 R-x R/W-0 — SOSCRUN — — SOSCGO — MFIOFS MFIOSEL bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 Unimplemented: Read as ‘0’ bit 6 SOSCRUN: SOSC Run Status bit 1 = System clock comes from a secondary SOSC 0 = System clock comes from an oscillator other than SOSC bit 5-4 Unimplemented: Read as ‘0’ bit 3 SOSCGO: Oscillator Start Control bit 1 = Oscillator is running, even if no other sources are requesting it 0 = Oscillator is shut off if no other sources are requesting it (When the SOSC is selected to run from a digital clock input, rather than an external crystal, this bit has no effect.) bit 2 Unimplemented: Read as ‘0’ bit 1 MFIOFS: MF-INTOSC Frequency Stable bit 1 = MF-INTOSC is stable 0 = MF-INTOSC is not stable bit 0 MFIOSEL: MF-INTOSC Select bit 1 = MF-INTOSC is used in place of HF-INTOSC frequencies of 500 kHz, 250 kHz and 31.25 kHz 0 = MF-INTOSC is not used DS39957B-page 42 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY REGISTER 3-3: OSCTUNE: OSCILLATOR TUNING REGISTER R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 INTSRC PLLEN TUN5 TUN4 TUN3 TUN2 TUN1 TUN0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 INTSRC: Internal Oscillator Low-Frequency Source Select bit 1 = 31.25 kHz device clock is derived from 16 MHz INTOSC source (divide-by-512 enabled, HF-INTOSC) 0 = 31 kHz device clock is derived from INTRC 31 kHz oscillator (LF-INTOSC) bit 6 PLLEN: Frequency Multiplier PLL Enable bit 1 = PLL is enabled 0 = PLL is disabled bit 5-0 TUN<5:0>: Fast RC Oscillator (INTOSC) Frequency Tuning bits 011111 = Maximum frequency • • 000001 000000 = Center frequency. Fast RC oscillator is running at the calibrated frequency. 111111 • • 100000 = Minimum frequency 3.3 Clock Sources and Oscillator Switching Essentially, PIC18F87K90 family devices have these independent clock sources: • Primary oscillators • Secondary oscillators • Internal oscillator The primary oscillators can be thought of as the main device oscillators. These are any external oscillators connected to the OSC1 and OSC2 pins, and include the External Crystal and Resonator modes and the External Clock modes. If selected by the OSC<3:0> Configuration bits (CONFIG1H<3:0>), the internal oscillator block may be considered a primary oscillator. The internal oscillator block can be one of the following: • 31 kHz LF-INTRC source • 31 kHz to 500 kHz MF-INTOSC source • 31 kHz to 16 MHz HF-INTOSC source The particular mode is defined by the OSC Configuration bits. The details of these modes are covered in Section 3.4 “External Oscillator Modes”. The secondary oscillators are external clock sources that are not connected to the OSC1 or OSC2 pin. These sources may continue to operate, even after the controller is placed in a power-managed mode. PIC18F87K90 family devices offer the SOSC 2010 Microchip Technology Inc. (Timer1/3/5/7) oscillator as a secondary oscillator source. This oscillator, in all power-managed modes, is often the time base for functions, such as a Real-Time Clock (RTC). The SOSCEN bit in the corresponding timer should be set correctly for the enabled SOSC. The SOSCEL<1:0> bits (CONFIG1L<4:3>) decide the SOSC mode of operation: • 11 = High-power SOSC circuit • 10 = Digital (SCLKI) mode • 01 = Low-power SOSC circuit In addition to being a primary clock source in some circumstances, the internal oscillator is available as a power-managed mode clock source. The LF-INTOSC source is also used as the clock source for several special features, such as the WDT and Fail-Safe Clock Monitor. The internal oscillator block is discussed in more detail in Section 3.6 “Internal Oscillator Block”. The PIC18F87K90 family includes features that allow the device clock source to be switched from the main oscillator, chosen by device configuration, to one of the alternate clock sources. When an alternate clock source is enabled, various power-managed operating modes are available. Preliminary DS39957B-page 43 PIC18F87K90 FAMILY 3.3.1 OSC1/OSC2 OSCILLATOR 3.3.2.1 The OSC1/OSC2 oscillator block is used to provide the oscillator modes and frequency ranges: Mode Design Operating Frequency LP 31.25-100 kHz XT 100 kHz to 4 MHz HS 4 MHz to 25 MHz EC 0 to 64 MHz (external clock) EXTRC 0 to 4 MHz (external RC) The crystal-based oscillators (XT, HS and LP) have a built-in start-up time. The operation of the EC and EXTRC clocks is immediate. 3.3.2 CLOCK SOURCE SELECTION The System Clock Select bits, SCS<1:>0 (OSCCON2<1:0>), select the clock source. The available clock sources are the primary clock defined by the OSC<3:0> Configuration bits, the secondary clock (SOSC oscillator) and the internal oscillator. The clock source changes after one or more of the bits is written to, following a brief clock transition interval. The OSTS (OSCCON<3>) and SOSCRUN (OSCCON2<6>) bits indicate which clock source is currently providing the device clock. The OSTS bit indicates that the Oscillator Start-up Timer (OST) has timed out and the primary clock is providing the device clock in primary clock modes. The SOSCRUN bit indicates when the SOSC oscillator (from Timer1/3/5/7) is providing the device clock in secondary clock modes. In power-managed modes, only one of these bits will be set at any time. If neither of these bits is set, the INTRC is providing the clock, or the internal oscillator has just started and is not yet stable. The IDLEN bit (OSCCON<7>) determines if the device goes into Sleep mode or one of the Idle modes when the SLEEP instruction is executed. The use of the flag and control bits in the OSCCON register is discussed in more detail in Section 4.0 “Power-Managed Modes”. Note 1: The secondary oscillator must be enabled to select the secondary clock source. The SOSC oscillator is enabled by setting the SOSCGO bit in the OSCCON2 register (OSCCON<3>). If the SOSC oscillator is not enabled, then any attempt to select a secondary clock source when executing a SLEEP instruction will be ignored. Since the SCS bits are cleared on all forms of Reset, this means the primary oscillator defined by the OSC<3:0> Configuration bits is used as the primary clock source on device Resets. This could either be the internal oscillator block by itself, or one of the other primary clock source (HS, EC, XT, LP, External RC and PLL-enabled modes). In those cases when the internal oscillator block, without PLL, is the default clock on Reset, the Fast RC oscillator (INTOSC) will be used as the device clock source. It will initially start at 8 MHz; the postscaler selection that corresponds to the Reset value of the IRCF<2:0> bits (‘110’). Regardless of which primary oscillator is selected, INTRC will always be enabled on device power-up. It serves as the clock source until the device has loaded its configuration values from memory. It is at this point that the OSC Configuration bits are read and the oscillator selection of the operational mode is made. Note that either the primary clock source or the internal oscillator will have two bit setting options for the possible values of the SCS<1:0> bits, at any given time. 3.3.3 OSCILLATOR TRANSITIONS PIC18F87K90 family devices contain circuitry to prevent clock “glitches” when switching between clock sources. A short pause in the device clock occurs during the clock switch. The length of this pause is the sum of two cycles of the old clock source and three to four cycles of the new clock source. This formula assumes that the new clock source is stable. Clock transitions are discussed in greater detail in Section 4.1.2 “Entering Power-Managed Modes”. 3.4 3.4.1 External Oscillator Modes CRYSTAL OSCILLATOR/CERAMIC RESONATORS (HS MODES) In HS or HSPLL Oscillator modes, a crystal or ceramic resonator is connected to the OSC1 and OSC2 pins to establish oscillation. Figure 3-2 shows the pin connections. The oscillator design requires the use of a crystal rated for parallel resonant operation. Note: 2: It is recommended that the secondary oscillator be operating and stable before executing the SLEEP instruction or a very long delay may occur while the SOSC oscillator starts. DS39957B-page 44 System Clock Selection and Device Resets Preliminary Use of a crystal rated for series resonant operation may give a frequency out of the crystal manufacturer’s specifications. 2010 Microchip Technology Inc. PIC18F87K90 FAMILY TABLE 3-2: CAPACITOR SELECTION FOR CERAMIC RESONATORS Typical Capacitor Values Used: Mode Freq. OSC1 OSC2 HS 8.0 MHz 16.0 MHz 27 pF 22 pF 27 pF 22 pF Note 1: Higher capacitance increases the stability of oscillator but also increases the start-up time. 2: Since each resonator/crystal has its own characteristics, the user should consult the resonator/crystal manufacturer for appropriate values of external components. Capacitor values are for design guidance only. Different capacitor values may be required to produce acceptable oscillator operation. The user should test the performance of the oscillator over the expected VDD and temperature range for the application. Refer to the following application notes for oscillator-specific information: • AN588, “PIC® Microcontroller Oscillator Design Guide” • AN826, “Crystal Oscillator Basics and Crystal Selection for rfPIC® and PIC® Devices” • AN849, “Basic PIC® Oscillator Design” • AN943, “Practical PIC® Oscillator Analysis and Design” • AN949, “Making Your Oscillator Work” 3: Rs may be required to avoid overdriving crystals with low drive level specification. 4: Always verify oscillator performance over the VDD and temperature range that is expected for the application. FIGURE 3-2: C1(1) HS CAPACITOR SELECTION FOR CRYSTAL OSCILLATOR Crystal Freq. RF(3) OSC2 C2(1) Osc Type OSC1 XTAL See the notes following Table 3-3 for additional information. TABLE 3-3: CRYSTAL/CERAMIC RESONATOR OPERATION (HS OR HSPLL CONFIGURATION) RS(2) To Internal Logic Sleep PIC18F87K90 Note 1: See Table 3-2 and Table 3-3 for initial values of C1 and C2. 2: A series resistor (RS) may be required for AT strip cut crystals. 3: RF varies with the oscillator mode chosen. Typical Capacitor Values Tested: C1 C2 4 MHz 27 pF 27 pF 3.5 8 MHz 22 pF 22 pF 20 MHz 15 pF 15 pF For timing-insensitive applications, the RC and RCIO Oscillator modes offer additional cost savings. The actual oscillator frequency is a function of several factors: Capacitor values are for design guidance only. Different capacitor values may be required to produce acceptable oscillator operation. The user should test the performance of the oscillator over the expected VDD and temperature range for the application. Refer to the Microchip application notes cited in Table 3-2 for oscillator-specific information. Also see the notes following this table for additional information. 2010 Microchip Technology Inc. RC Oscillator • Supply voltage • Values of the external resistor (REXT) and capacitor (CEXT) • Operating temperature – Given the same device, operating voltage and temperature and component values, there will also be unit-to-unit frequency variations. These are due to factors such as: - normal manufacturing variation - difference in lead frame capacitance between package types (especially for low CEXT values) - variations within the tolerance of limits of REXT and CEXT Preliminary DS39957B-page 45 PIC18F87K90 FAMILY In the RC Oscillator mode, the oscillator frequency divided by 4 is available on the OSC2 pin. This signal may be used for test purposes or to synchronize other logic. Figure 3-3 shows how the R/C combination is connected. FIGURE 3-3: RC OSCILLATOR MODE FIGURE 3-5: EXTERNAL CLOCK INPUT OPERATION (EC CONFIGURATION) OSC1/CLKI Clock from Ext. System VDD PIC18F87K90 FOSC/4 REXT Internal Clock OSC1 CEXT PIC18FXXXX VSS FOSC/4 OSC2/CLKO Recommended values: 3 k REXT 100 k 20 pF CEXT 300 pF The RCIO Oscillator mode (Figure 3-4) functions like the RC mode, except that the OSC2 pin becomes an additional general purpose I/O pin. The I/O pin becomes bit 6 of PORTA (RA6). FIGURE 3-4: RCIO OSCILLATOR MODE OSC2/CLKO An external clock source may also be connected to the OSC1 pin in the HS mode, as shown in Figure 3-6. In this configuration, the divide-by-4 output on OSC2 is not available. Current consumption in this configuration will be somewhat higher than EC mode, as the internal oscillator’s feedback circuitry will be enabled (in EC mode, the feedback circuit is disabled). FIGURE 3-6: EXTERNAL CLOCK INPUT OPERATION (HS OSC CONFIGURATION) OSC1 Clock from Ext. System PIC18F87K90 (HS Mode) VDD Open REXT Internal Clock OSC1 3.5.2 CEXT PIC18FXXXX VSS RA6 I/O (OSC2) Recommended values: 3 k REXT 100 k 20 pF CEXT 300 pF 3.5.1 EXTERNAL CLOCK INPUT (EC MODES) In the EC Oscillator mode, the oscillator frequency divided by 4 is available on the OSC2 pin. This signal may be used for test purposes or to synchronize other logic. Figure 3-5 shows the pin connections for the EC Oscillator mode. PLL FREQUENCY MULTIPLIER A Phase Lock Loop (PLL) circuit is provided as an option for users who want to use a lower frequency oscillator circuit, or to clock the device up to its highest rated frequency from a crystal oscillator. This may be useful for customers who are concerned with EMI due to high-frequency crystals, or users who require higher clock speeds from an internal oscillator. 3.5.2.1 The EC and ECPLL Oscillator modes require an external clock source to be connected to the OSC1 pin. There is no oscillator start-up time required after a Power-on Reset or after an exit from Sleep mode. OSC2 HSPLL and ECPLL Modes The HSPLL and ECPLL modes provide the ability to selectively run the device at four times the external oscillating source to produce frequencies up to 64 MHz. The PLL is enabled by setting the PLLEN bit (OSCTUNE<6>) or the PLLCFG bit (CONFIG1H<4>). For the HF-INTOSC as primary, the PLL must be enabled with the PLLEN. This provides software control for the PLL, enabling even if PLLCFG is set to ‘1’, so that the PLL is enabled only when the HF-INTOSC frequency is within the 4 MHz to 16 MHz input range. This also enables additional flexibility for controlling the application’s clock speed in software. The PLLEN should be enabled in HF-INTOSC mode only if the input frequency is in the range of 4 MHz-16 MHz. DS39957B-page 46 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY FIGURE 3-7: PLL BLOCK DIAGRAM For MF-INTOSC mode to provide a frequency range of 500 kHz to 31 kHz, INTSRC = 1 and MFIOSEL = 1. The postscaler (IRCF<2:0>), in this mode, provides the frequency range of 31 kHz to 500 kHz. The LF-INTRC can provide only 31 kHz if INTSRC = 0. PLLCFG (CONFIG1H<4>) PLL Enable (OSCTUNE) OSC2 OSC1 HS or EC Mode FIN Phase Comparator FOUT Loop Filter VCO MUX 4 3.5.2.2 SYSCLK PLL and HF-INTOSC The operation of INTOSC with the PLL is described in Section 3.6.2 “INTPLL Modes”. Care should be taken that the PLL is enabled only if the HF-INTOSC postscaler is configured for 4 MHz, 8 MHz or 16 MHz. Internal Oscillator Block The PIC18F87K90 family of devices includes an internal oscillator block which generates two different clock signals. Either clock can be used as the microcontroller’s clock source, which may eliminate the need for an external oscillator circuit on the OSC1 and/or OSC2 pins. The internal oscillator consists of three blocks, depending on the frequency of operation. They are HF-INTOSC, MF-INTOSC and LF-INTRC. In HF-INTOSC mode, the internal oscillator can provide a frequency, ranging from 31 KHz to 16 MHz, with the postscaler deciding the selected frequency (IRCF<2:0>). The INTSRC bit (OSCTUNE<7>) and MFIOSEL bit (OSCCON2<0>) also decide which INTOSC provides the lower frequency (500 kHz to 31 KHz). For the HF-INTOSC to provide these frequencies, INTSRC = 1 and MFI0SEL = 0. In HF-INTOSC, the postscaler (IRCF<2:0>) provides the frequency range of 31 kHz to 16 MHz. If HF-INTOSC is used with the PLL, the input frequency to the PLL should be 4 MHz to 16 MHz (IRCF<2:0> = 111, 110 or 101). 2010 Microchip Technology Inc. is is is in The clock source frequency (HF-INTOSC, MF-INTOSC or LF-INTRC direct) is selected by configuring the IRCF bits of the OSCCON register, as well the INTSRC and MFIOSEL bits. The default frequency on device Resets is 8 MHz. The PLL is available to the internal oscillator block when the internal oscillator block is configured as the primary clock source. In this configuration, the PLL is enabled in software and generates a clock output of up to 64 MHz. 3.6 The LF-INTRC provides 31 kHz and is enabled if it selected as the device clock source. The mode enabled automatically when any of the following enabled: • Power-up Timer • Fail-Safe Clock Monitor • Watchdog Timer • Two-Speed Start-up These features are discussed in greater detail Section 28.0 “Special Features of the CPU”. 3.6.1 INTIO MODES Using the internal oscillator as the clock source eliminates the need for up to two external oscillator pins, which can then be used for digital I/O. Two distinct oscillator configurations, which are determined by the OSC Configuration bits, are available: • In INTIO1 mode, the OSC2 pin (RA6) outputs FOSC/4, while OSC1 functions as RA7 (see Figure 3-8) for digital input and output. • In INTIO2 mode, OSC1 functions as RA7 and OSC2 functions as RA6 (see Figure 3-9). Both are available as digital input and output ports. FIGURE 3-8: RA7 INTIO1 OSCILLATOR MODE I/O (OSC1) PIC18F87K90 FOSC/4 FIGURE 3-9: Preliminary RA7 OSC2 INTIO2 OSCILLATOR MODE I/O (OSC1) PIC18F87K90 RA6 I/O (OSC2) DS39957B-page 47 PIC18F87K90 FAMILY 3.6.2 INTPLL MODES The 4x Phase Locked Loop (PLL) can be used with the HF-INTOSC to produce faster device clock speeds than are normally possible with the internal oscillator sources. When enabled, the PLL produces a clock speed of 16 MHz or 64 MHz. PLL operation is controlled through software. The control bits, PLLEN (OSCTUNE<6>) and PLLCFG (CONFIG1H<4>), are used to enable or disable its operation. The PLL is available only to HF-INTOSC and the other oscillator is set with HS and EC modes. Additionally, the PLL will only function when the selected output frequency is either 4 MHz or 16 MHz (OSCCON<6:4> = 111, 110 or 101). Like the INTIO modes, there are two distinct INTPLL modes available: • In INTPLL1 mode, the OSC2 pin outputs FOSC/4, while OSC1 functions as RA7 for digital input and output. Externally, this is identical in appearance to INTIO1 (Figure 3-8). • In INTPLL2 mode, OSC1 functions as RA7 and OSC2 functions as RA6, both for digital input and output. Externally, this is identical to INTIO2 (Figure 3-9). 3.6.3 INTERNAL OSCILLATOR OUTPUT FREQUENCY AND TUNING The internal oscillator block is calibrated at the factory to produce an INTOSC output frequency of 16 MHz. It can be adjusted in the user’s application by writing to TUN<5:0> (OSCTUNE<5:0>) in the OSCTUNE register (Register 3-3). When the OSCTUNE register is modified, the INTOSC (HF-INTOSC and MF-INTOSC) frequency will begin shifting to the new frequency. The oscillator will require some time to stabilize. Code execution continues during this shift and there is no indication that the shift has occurred. The LF-INTOSC oscillator operates independently of the HF-INTOSC or the MF-INTOSC source. Any changes in the HF-INTOSC or the MF-INTOSC source, across voltage and temperature, are not necessarily reflected by changes in LF-INTOSC or vice versa. The frequency of LF-INTOSC is not affected by OSCTUNE. 3.6.4 INTOSC FREQUENCY DRIFT The INTOSC frequency may drift as VDD or temperature changes, and can affect the controller operation in a variety of ways. It is possible to adjust the INTOSC frequency by modifying the value in the OSCTUNE register. Depending on the device, this may have no effect on the LF-INTOSC clock source frequency. DS39957B-page 48 Tuning INTOSC requires knowing when to make the adjustment, in which direction it should be made, and in some cases, how large a change is needed. Three compensation techniques are shown here. 3.6.4.1 Compensating with the EUSART An adjustment may be required when the EUSART begins to generate framing errors or receives data with errors while in Asynchronous mode. Framing errors indicate that the device clock frequency is too high. To adjust for this, decrement the value in OSCTUNE to reduce the clock frequency. On the other hand, errors in data may suggest that the clock speed is too low. To compensate, increment OSCTUNE to increase the clock frequency. 3.6.4.2 Compensating with the Timers This technique compares device clock speed to some reference clock. Two timers may be used; one timer is clocked by the peripheral clock, while the other is clocked by a fixed reference source, such as the SOSC oscillator. Both timers are cleared, but the timer clocked by the reference generates interrupts. When an interrupt occurs, the internally clocked timer is read and both timers are cleared. If the internally clocked timer value is much greater than expected, then the internal oscillator block is running too fast. To adjust for this, decrement the OSCTUNE register. 3.6.4.3 Compensating with the CCP Module in Capture Mode A CCP module can use free-running Timer1 (or Timer3), clocked by the internal oscillator block and an external event with a known period (i.e., AC power frequency). The time of the first event is captured in the CCPRxH:CCPRxL registers and is recorded for use later. When the second event causes a capture, the time of the first event is subtracted from the time of the second event. Since the period of the external event is known, the time difference between events can be calculated. If the measured time is much greater than the calculated time, the internal oscillator block is running too fast. To compensate, decrement the OSCTUNE register. If the measured time is much less than the calculated time, the internal oscillator block is running too slow. To compensate, increment the OSCTUNE register. Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 3.7 Reference Clock Output In addition to the FOSC/4 clock output in certain oscillator modes, the device clock in the PIC18F87K90 family can also be configured to provide a reference clock output signal to a port pin. This feature is available in all oscillator configurations and allows the user to select a greater range of clock submultiples to drive external devices in the application. This reference clock output is controlled by the REFOCON register (Register 3-4). Setting the ROON bit (REFOCON<7>) makes the clock signal available on the REFO (RE3) pin. The RODIV<3:0> bits enable the selection of 16 different clock divider options. REGISTER 3-4: R/W-0 To use the reference clock output in Sleep mode, both the ROSSLP and ROSEL bits must be set. The device clock must also be configured for an EC or HS mode; otherwise, the oscillator on OSC1 and OSC2 will be powered down when the device enters Sleep mode. Clearing the ROSEL bit allows the reference output frequency to change as the system clock changes during any clock switches. REFOCON: REFERENCE OSCILLATOR CONTROL REGISTER U-0 ROON The ROSSLP and ROSEL bits (REFOCON<5:4>) control the availability of the reference output during Sleep mode. The ROSEL bit determines if the oscillator on OSC1 and OSC2, or the current system clock source, is used for the reference clock output. The ROSSLP bit determines if the reference source is available on RE3 when the device is in Sleep mode. — R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 ROSSLP ROSEL(1) RODIV3 RODIV2 RODIV1 RODIV0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 ROON: Reference Oscillator Output Enable bit 1 = Reference oscillator output is available on REFO pin 0 = Reference oscillator output is disabled bit 6 Unimplemented: Read as ‘0’ bit 5 ROSSLP: Reference Oscillator Output Stop in Sleep bit 1 = Reference oscillator continues to run in Sleep 0 = Reference oscillator is disabled in Sleep bit 4 ROSEL: Reference Oscillator Source Select bit(1) 1 = Primary oscillator (EC or HS) is used as the base clock 0 = System clock is used as the base clock; base clock reflects any clock switching of the device bit 3-0 RODIV<3:0>: Reference Oscillator Divisor Select bits 1111 = Base clock value divided by 32,768 1110 = Base clock value divided by 16,384 1101 = Base clock value divided by 8,192 1100 = Base clock value divided by 4,096 1011 = Base clock value divided by 2,048 1010 = Base clock value divided by 1,024 1001 = Base clock value divided by 512 1000 = Base clock value divided by 256 0111 = Base clock value divided by 128 0110 = Base clock value divided by 64 0101 = Base clock value divided by 32 0100 = Base clock value divided by 16 0011 = Base clock value divided by 8 0010 = Base clock value divided by 4 0001 = Base clock value divided by 2 0000 = Base clock value Note 1: For ROSEL (REFOCON<4>), the primary oscillator is only available when configured as default via the FOSC settings (regardless of whether the device is in Sleep mode). 2010 Microchip Technology Inc. Preliminary DS39957B-page 49 PIC18F87K90 FAMILY 3.8 Effects of Power-Managed Modes on the Various Clock Sources When PRI_IDLE mode is selected, the designated primary oscillator continues to run without interruption. For all other power-managed modes, the oscillator using the OSC1 pin is disabled. The OSC1 pin (and OSC2 pin if used by the oscillator) will stop oscillating. In secondary clock modes (SEC_RUN and SEC_IDLE), the SOSC oscillator is operating and providing the device clock. The SOSC oscillator may also run in all power-managed modes if required to clock SOSC. In RC_RUN and RC_IDLE modes, the internal oscillator provides the device clock source. The 31 kHz LF-INTOSC output can be used directly to provide the clock and may be enabled to support various special features, regardless of the power-managed mode (see Section 28.2 “Watchdog Timer (WDT)” through Section 28.5 “Fail-Safe Clock Monitor” for more information on WDT, Fail-Safe Clock Monitor and Two-Speed Start-up). If the Sleep mode is selected, all clock sources are stopped. Since all the transistor switching currents have been stopped, Sleep mode achieves the lowest current consumption of the device (only leakage currents). Enabling any on-chip feature that will operate during Sleep will increase the current consumed during Sleep. The INTOSC is required to support WDT operation. TABLE 3-4: The SOSC oscillator may be operating to support a Real-Time Clock (RTC). Other features may be operating that do not require a device clock source (i.e., MSSP slave, INTx pins and others). Peripherals that may add significant current consumption are listed in Section 31.2 “DC Characteristics: Power-Down and Supply Current PIC18F87K90 Family (Industrial)”. 3.9 Power-up Delays Power-up delays are controlled by two timers, so that no external Reset circuitry is required for most applications. The delays ensure that the device is kept in Reset until the device power supply is stable under normal circumstances and the primary clock is operating and stable. For additional information on power-up delays, see Section 5.6 “Power-up Timer (PWRT)”. The first timer is the Power-up Timer (PWRT), which provides a fixed delay on power-up time of about 64 ms (parameter 33, Table 31-10); it is always enabled. The second timer is the Oscillator Start-up Timer (OST), intended to keep the chip in Reset until the crystal oscillator is stable (HS, XT or LP modes). The OST does this by counting 1,024 oscillator cycles before allowing the oscillator to clock the device. There is a delay of interval, TCSD (parameter 38, Table 31-10), following POR, while the controller becomes ready to execute instructions. OSC1 AND OSC2 PIN STATES IN SLEEP MODE Oscillator Mode OSC1 Pin OSC2 Pin EC, ECPLL Floating, pulled by external clock At logic low (clock/4 output) HS, HSPLL Feedback inverter disabled at quiescent voltage level Feedback inverter disabled at quiescent voltage level INTOSC, INTPLL1/2 I/O pin, RA6, direction controlled by TRISA<6> I/O pin, RA6, direction controlled by TRISA<7> Note: See Section 5.0 “Reset” for time-outs due to Sleep and MCLR Reset. DS39957B-page 50 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 4.0 POWER-MANAGED MODES The PIC18F87K90 family of devices offers a total of seven operating modes for more efficient power management. These modes provide a variety of options for selective power conservation in applications where resources may be limited (such as battery-powered devices). There are three categories of power-managed modes: • Run modes • Idle modes • Sleep mode There is an Ultra Low-Power Wake-up (ULPWU) for waking from the Sleep mode. These categories define which portions of the device are clocked, and sometimes, at what speed. The Run and Idle modes may use any of the three available clock sources (primary, secondary or internal oscillator block). The Sleep mode does not use a clock source. The ULPWU mode, on the RA0 pin, enables a slow falling voltage to generate a wake-up, even from Sleep, without excess current consumption. (See Section 4.7 “Ultra Low-Power Wake-up”.) The power-managed modes include several powersaving features offered on previous PIC® devices. One is the clock switching feature, offered in other PIC18 devices. This feature allows the controller to use the SOSC oscillator instead of the primary one. Another power-saving feature is Sleep mode, offered by all PIC devices, where all device clocks are stopped. 4.1 Selecting Power-Managed Modes Selecting a power-managed mode requires two decisions: • Will the CPU be clocked or not • What will be the clock source TABLE 4-1: 4.1.1 CLOCK SOURCES The SCS<1:0> bits select one of three clock sources for power-managed modes. Those sources are: • The primary clock, as defined by the OSC<3:0> Configuration bits • The secondary clock (the SOSC oscillator) • The internal oscillator block (for LF-INTOSC modes) 4.1.2 ENTERING POWER-MANAGED MODES Switching from one power-managed mode to another begins by loading the OSCCON register. The SCS<1:0> bits select the clock source and determine which Run or Idle mode is used. Changing these bits causes an immediate switch to the new clock source, assuming that it is running. The switch may also be subject to clock transition delays. These considerations are discussed in Section 4.1.3 “Clock Transitions and Status Indicators” and subsequent sections. Entering the power-managed Idle or Sleep modes is triggered by the execution of a SLEEP instruction. The actual mode that results depends on the status of the IDLEN bit. Depending on the current and impending mode, a change to a power-managed mode does not always require setting all of the previously discussed bits. Many transitions can be done by changing the oscillator select bits, or changing the IDLEN bit, prior to issuing a SLEEP instruction. If the IDLEN bit is already configured as desired, it may only be necessary to perform a SLEEP instruction to switch to the desired mode. POWER-MANAGED MODES OSCCON Bits Mode The IDLEN bit (OSCCON<7>) controls CPU clocking, while the SCS<1:0> bits (OSCCON<1:0>) select the clock source. The individual modes, bit settings, clock sources and affected modules are summarized in Table 4-1. Module Clocking Available Clock and Oscillator Source IDLEN<7>(1) SCS<1:0> CPU Peripherals 0 N/A Off Off PRI_RUN N/A 00 Clocked Clocked Primary – XT, LP, HS, EC, RC and PLL modes. This is the normal, full-power execution mode. SEC_RUN N/A 01 Clocked Clocked Secondary – SOSC Oscillator RC_RUN N/A 1x Clocked Clocked Internal oscillator block(2) PRI_IDLE 1 00 Off Clocked Primary – LP, XT, HS, RC, EC SEC_IDLE 1 01 Off Clocked Secondary – SOSC oscillator RC_IDLE 1 1x Off Clocked Internal oscillator block(2) Sleep Note 1: 2: None – All clocks are disabled IDLEN reflects its value when the SLEEP instruction is executed. Includes INTOSC (HF-INTOSC and MG-INTOSC) and INTOSC postscaler, as well as the LF-INTISC source. 2010 Microchip Technology Inc. Preliminary DS39957B-page 51 PIC18F87K90 FAMILY 4.1.3 CLOCK TRANSITIONS AND STATUS INDICATORS The length of the transition between clock sources is the sum of two cycles of the old clock source and three to four cycles of the new clock source. This formula assumes that the new clock source is stable. The HFINTOSC and MF-INTOSC are termed as INTOSC in this chapter. Three bits indicate the current clock source and its status, as shown in Table 4-2. The three bits are: • OSTS (OSCCON<3>) • HFIOFS (OSCCON<2>) • SOSCRUN (OSCCON2<6>) TABLE 4-2: HFIOFS or OSTS SOSCRUN MFIOFS Primary Oscillator 1 0 0 INTOSC (HF-INTOSC or MF-INTOSC) 0 1 0 Secondary Oscillator 0 0 1 MF-INTOSC or HF-INTOSC as Primary Clock Source 1 1 0 LF-INTOSC is Running or INTOSC is Not Yet Stable 0 The power-managed mode that is invoked with the SLEEP instruction is determined by the setting of the IDLEN bit at the time the instruction is executed. If another SLEEP instruction is executed, the device will enter the power-managed mode specified by IDLEN at that time. If IDLEN has changed, the device will enter the new power-managed mode specified by the new setting. 4.2 0 4.2.1 Run Modes 0 If the internal oscillator block is configured as the primary clock source by the OSC<3:0> Configuration bits (CONFIG1H<3:0>). Then, the OSTS and HFIOFS or MFIOFS bits can be set when in PRI_RUN or PRI_IDLE modes. This indicates that the primary clock (INTOSC output) is generating a stable output. Entering another INTOSC power-managed mode at the same frequency would clear the OSTS bit. Note 1: Caution should be used when modifying a single IRCF bit. At a lower VDD, it is possible to select a higher clock speed than is supportable by that VDD. Improper device operation may result if the VDD/ FOSC specifications are violated. 2: Executing a SLEEP instruction does not necessarily place the device into Sleep mode. It acts as the trigger to place the controller into either the Sleep mode or one of the Idle modes, depending on the setting of the IDLEN bit. PRI_RUN MODE The PRI_RUN mode is the normal, full-power execution mode of the microcontroller. This is also the default mode upon a device Reset, unless Two-Speed Start-up is enabled. (For details, see Section 28.4 “Two-Speed Start-up”.) In this mode, the OSTS bit is set. The HFIOFS or MFIOFS bit may be set if the internal oscillator block is the primary clock source. (See Section 3.2 “Control Registers”.) 4.2.2 When the OSTS bit is set, the primary clock is providing the device clock. When the HFIOFS or MFIOFS bit is set, the INTOSC output is providing a stable clock source to a divider that actually drives the device clock. When the SOSCRUN bit is set, the SOSC oscillator is providing the clock. If none of these bits are set, either the LF-INTOSC clock source is clocking the device or the INTOSC source is not yet stable. DS39957B-page 52 MULTIPLE SLEEP COMMANDS In the Run modes, clocks to both the core and peripherals are active. The difference between these modes is the clock source. SYSTEM CLOCK INDICATOR Main Clock Source 4.1.4 SEC_RUN MODE The SEC_RUN mode is the compatible mode to the “clock-switching” feature offered in other PIC18 devices. In this mode, the CPU and peripherals are clocked from the SOSC oscillator. This enables lower power consumption while retaining a high-accuracy clock source. SEC_RUN mode is entered by setting the SCS<1:0> bits to ‘01’. The device clock source is switched to the SOSC oscillator (see Figure 4-1), the primary oscillator is shut down, the SOSCRUN bit (OSCCON2<6>) is set and the OSTS bit is cleared. Note: The SOSC oscillator can be enabled by setting the SOSCGO bit (OSCCON2<3>). If this bit is set, the clock switch to the SEC_RUN mode can switch immediately once SCS<1:0> are set to ‘01’. On transitions from SEC_RUN mode to PRI_RUN mode, the peripherals and CPU continue to be clocked from the SOSC oscillator while the primary clock is started. When the primary clock becomes ready, a clock switch back to the primary clock occurs (see Figure 4-2). When the clock switch is complete, the SOSCRUN bit is cleared, the OSTS bit is set and the primary clock is providing the clock. The IDLEN and SCS bits are not affected by the wake-up and the SOSC oscillator continues to run. Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY FIGURE 4-1: TRANSITION TIMING FOR ENTRY TO SEC_RUN MODE Q1 Q2 Q3 Q4 Q1 Q2 1 SOSCI 2 3 n-1 Q3 Q4 Q1 Q2 Q3 n Clock Transition(1) OSC1 CPU Clock Peripheral Clock Program Counter PC PC + 2 PC + 4 Note 1: Clock transition typically occurs within 2-4 TOSC. FIGURE 4-2: TRANSITION TIMING FROM SEC_RUN MODE TO PRI_RUN MODE (HSPLL) Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 SOSC OSC1 TOST(1) TPLL(1) 1 PLL Clock Output 2 n-1 n Clock Transition(2) CPU Clock Peripheral Clock Program Counter PC + 2 PC SCS<1:0> bits Changed PC + 4 OSTS bit Set Note 1: TOST = 1024 TOSC; TPLL = 2 ms (approx). These intervals are not shown to scale. 2: Clock transition typically occurs within 2-4 TOSC. 4.2.3 RC_RUN MODE In RC_RUN mode, the CPU and peripherals are clocked from the internal oscillator block using the INTOSC multiplexer. In this mode, the primary clock is shut down. When using the LF-INTOSC source, this mode provides the best power conservation of all the Run modes, while still executing code. It works well for user applications which are not highly timing-sensitive or do not require high-speed clocks at all times. This mode is entered by setting the SCS1 bit to ‘1’. To maintain software compatibility with future devices, it is recommended that the SCS0 bit also be cleared, even though the bit is ignored. When the clock source is switched to the INTOSC multiplexer (see Figure 4-3), the primary oscillator is shut down and the OSTS bit is cleared. The IRCF bits may be modified at any time to immediately change the clock speed. Note: If the primary clock source is the internal oscillator block – either LF-INTOSC or INTOSC (MF-INTOSC or HF-INTOSC) – there are no distinguishable differences between the PRI_RUN and RC_RUN modes during execution. Entering or exiting RC_RUN mode, however, causes a clock switch delay. Therefore, if the primary clock source is the internal oscillator block, using RC_RUN mode is not recommended. 2010 Microchip Technology Inc. Preliminary Caution should be used when modifying a single IRCF bit. At a lower VDD, it is possible to select a higher clock speed than is supportable by that VDD. Improper device operation may result if the VDD/ FOSC specifications are violated. DS39957B-page 53 PIC18F87K90 FAMILY If the IRCF bits and the INTSRC bit are all clear, the INTOSC output (HF-INTOSC/MF-INTOSC) is not enabled and the HFIOFS and MFIOFS bits will remain clear. There will be no indication of the current clock source. The LF-INTOSC source is providing the device clocks. TABLE 4-3: If the IRCF bits are changed from all clear (thus, enabling the INTOSC output) or if INTSRC or MFIOSEL is set, the HFIOFS or MFIOFS bit is set after the INTOSC output becomes stable. For details, see Table 4-3. INTERNAL OSCILLATOR FREQUENCY STABILITY BITS IRCF<2:0> INTSRC MFIOSEL Status of MFIOFS or HFIOFS when INTOSC is Stable 000 0 x MFIOFS = 0, HFIOFS = 0 and clock source is LF-INTOSC 000 1 0 MFIOFS = 0, HFIOFS = 1 and clock source is HF-INTOSC 000 1 1 MFIOFS = 1, HFIOFS = 0 and clock source is MF-INTOSC Non-Zero x 0 MFIOFS = 0, HFIOFS = 1 and clock source is HF-INTOSC Non-Zero x 1 MFIOFS = 1, HFIOFS = 0 and clock source is MF-INTOSC Clocks to the device continue while the INTOSC source stabilizes after an interval of TIOBST (parameter 39, Table 31-10). If the IRCF bits were previously at a non-zero value, or if INTSRC was set before setting SCS1 and the INTOSC source was already stable, the HFIOFS or MFIOFS bit will remain set. DS39957B-page 54 On transitions from RC_RUN mode to PRI_RUN mode, the device continues to be clocked from the INTOSC multiplexer while the primary clock is started. When the primary clock becomes ready, a clock switch to the primary clock occurs (see Figure 4-4). When the clock switch is complete, the HFIOFS or MFIOFS bit is cleared, the OSTS bit is set and the primary clock is providing the device clock. The IDLEN and SCS bits are not affected by the switch. The LF-INTOSC source will continue to run if either the WDT or the Fail-Safe Clock Monitor is enabled. Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY FIGURE 4-3: TRANSITION TIMING TO RC_RUN MODE Q1 Q2 Q3 Q4 Q1 Q2 1 LF-INTOSC 2 3 n-1 Q3 Q4 Q1 Q2 Q3 n Clock Transition(1) OSC1 CPU Clock Peripheral Clock Program Counter PC PC + 2 PC + 4 Note 1: Clock transition typically occurs within 2-4 TOSC. FIGURE 4-4: TRANSITION TIMING FROM RC_RUN MODE TO PRI_RUN MODE Q1 Q2 Q3 Q4 Q2 Q3 Q4 Q1 Q2 Q3 Q1 INTOSC Multiplexer OSC1 TOST(1) TPLL(1) 1 PLL Clock Output 2 n-1 n Clock Transition(2) CPU Clock Peripheral Clock Program Counter SCS<1:0> bits Changed PC + 2 PC PC + 4 OSTS bit Set Note1: TOST = 1024 TOSC; TPLL = 2 ms (approx). These intervals are not shown to scale. 2: Clock transition typically occurs within 2-4 TOSC. 2010 Microchip Technology Inc. Preliminary DS39957B-page 55 PIC18F87K90 FAMILY 4.3 Sleep Mode 4.4 The power-managed Sleep mode in the PIC18F87K90 family of devices is identical to the legacy Sleep mode offered in all other PIC devices. It is entered by clearing the IDLEN bit (the default state on device Reset) and executing the SLEEP instruction. This shuts down the selected oscillator (Figure 4-5). All clock source status bits are cleared. Idle Modes The Idle modes allow the controller’s CPU to be selectively shut down while the peripherals continue to operate. Selecting a particular Idle mode allows users to further manage power consumption. If the IDLEN bit is set to a ‘1’ when a SLEEP instruction is executed, the peripherals will be clocked from the clock source selected using the SCS<1:0> bits. The CPU, however, will not be clocked. The clock source status bits are not affected. This approach is a quick method to switch from a given Run mode to its corresponding Idle mode. Entering Sleep mode from any other mode does not require a clock switch. This is because no clocks are needed once the controller has entered Sleep. If the WDT is selected, the LF-INTOSC source will continue to operate. If the SOSC oscillator is enabled, it will also continue to run. If the WDT is selected, the LF-INTOSC source will continue to operate. If the SOSC oscillator is enabled, it will also continue to run. When a wake event occurs in Sleep mode (by interrupt, Reset or WDT time-out), the device will not be clocked until the clock source selected by the SCS<1:0> bits becomes ready (see Figure 4-6). Alternately, the device will be clocked from the internal oscillator block if either the Two-Speed Start-up or the Fail-Safe Clock Monitor is enabled (see Section 28.0 “Special Features of the CPU”). In either case, the OSTS bit is set when the primary clock is providing the device clocks. The IDLEN and SCS bits are not affected by the wake-up. Since the CPU is not executing instructions, the only exits from any of the Idle modes are by interrupt, WDT time-out or a Reset. When a wake event occurs, CPU execution is delayed by an interval of TCSD (parameter 38, Table 31-10) while it becomes ready to execute code. When the CPU begins executing code, it resumes with the same clock source for the current Idle mode. For example, when waking from RC_IDLE mode, the internal oscillator block will clock the CPU and peripherals (in other words, RC_RUN mode). The IDLEN and SCS bits are not affected by the wake-up. While in any Idle mode or Sleep mode, a WDT timeout will result in a WDT wake-up to the Run mode currently specified by the SCS<1:0> bits. FIGURE 4-5: TRANSITION TIMING FOR ENTRY TO SLEEP MODE Q1 Q2 Q3 Q4 Q1 OSC1 CPU Clock Peripheral Clock Sleep Program Counter PC FIGURE 4-6: PC + 2 TRANSITION TIMING FOR WAKE FROM SLEEP (HSPLL) Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 OSC1 PLL Clock Output TOST(1) TPLL(1) CPU Clock Peripheral Clock Program Counter PC + 2 PC Wake Event PC + 4 PC + 6 OSTS bit Set Note1: TOST = 1024 TOSC; TPLL = 2 ms (approx). These intervals are not shown to scale. DS39957B-page 56 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 4.4.1 PRI_IDLE MODE 4.4.2 This mode is unique among the three low-power Idle modes, in that it does not disable the primary device clock. For timing-sensitive applications, this allows for the fastest resumption of device operation with its more accurate, primary clock source, since the clock source does not have to “warm-up” or transition from another oscillator. PRI_IDLE mode is entered from PRI_RUN mode by setting the IDLEN bit and executing a SLEEP instruction. If the device is in another Run mode, set IDLEN first, then clear the SCS bits and execute SLEEP. Although the CPU is disabled, the peripherals continue to be clocked from the primary clock source specified by the OSC<3:0> Configuration bits. The OSTS bit remains set (see Figure 4-7). SEC_IDLE MODE In SEC_IDLE mode, the CPU is disabled but the peripherals continue to be clocked from the SOSC oscillator. This mode is entered from SEC_RUN by setting the IDLEN bit and executing a SLEEP instruction. If the device is in another Run mode, set the IDLEN bit first, then set the SCS<1:0> bits to ‘01’ and execute SLEEP. When the clock source is switched to the SOSC oscillator, the primary oscillator is shut down, the OSTS bit is cleared and the SOSCRUN bit is set. When a wake event occurs, the peripherals continue to be clocked from the SOSC oscillator. After an interval of TCSD following the wake event, the CPU begins executing code being clocked by the SOSC oscillator. The IDLEN and SCS bits are not affected by the wake-up and the SOSC oscillator continues to run (see Figure 4-8). When a wake event occurs, the CPU is clocked from the primary clock source. A delay of interval, TCSD (parameter 39, Table 31-10), is required between the wake event and the start of code execution. This is required to allow the CPU to become ready to execute instructions. After the wake-up, the OSTS bit remains set. The IDLEN and SCS bits are not affected by the wake-up (see Figure 4-8). FIGURE 4-7: TRANSITION TIMING FOR ENTRY TO IDLE MODE Q1 Q4 Q3 Q2 Q1 OSC1 CPU Clock Peripheral Clock Program Counter PC FIGURE 4-8: PC + 2 TRANSITION TIMING FOR WAKE FROM IDLE TO RUN MODE Q1 Q2 Q3 Q4 OSC1 TCSD CPU Clock Peripheral Clock Program Counter PC Wake Event 2010 Microchip Technology Inc. Preliminary DS39957B-page 57 PIC18F87K90 FAMILY 4.4.3 4.5 RC_IDLE MODE In RC_IDLE mode, the CPU is disabled but the peripherals continue to be clocked from the internal oscillator block using the INTOSC multiplexer. This mode provides controllable power conservation during Idle periods. From RC_RUN, this mode is entered by setting the IDLEN bit and executing a SLEEP instruction. If the device is in another Run mode, first set IDLEN, then set the SCS1 bit and execute SLEEP. To maintain software compatibility with future devices, it is recommended that SCS0 also be cleared, though its value is ignored. The INTOSC multiplexer may be used to select a higher clock frequency by modifying the IRCF bits before executing the SLEEP instruction. When the clock source is switched to the INTOSC multiplexer, the primary oscillator is shut down and the OSTS bit is cleared. If the IRCF bits are set to any non-zero value, or the INTSRC/MFIOSEL bit is set, the INTOSC output is enabled. The HFIOFS/MFIOFS bits become set, after the INTOSC output becomes stable after an interval of TIOBST (parameter 38, Table 31-10). (For information on the HFIOFS/MFIOFS bits, see Table 4-3.) Clocks to the peripherals continue while the INTOSC source stabilizes. The HFIOFS/MFIOFS bits will remain set if the IRCF bits were previously at a nonzero value or if INTSRC was set before the SLEEP instruction was executed and the INTOSC source was already stable. If the IRCF bits and INTSRC are all clear, the INTOSC output will not be enabled, the HFIOFS/MFIOFS bits will remain clear and there will be no indication of the current clock source. When a wake event occurs, the peripherals continue to be clocked from the INTOSC multiplexer. After a delay of TCSD (parameter 38, Table 31-10), following the wake event, the CPU begins executing code clocked by the INTOSC multiplexer. The IDLEN and SCS bits are not affected by the wake-up. The INTRC source will continue to run if either the WDT or the Fail-Safe Clock Monitor is enabled. DS39957B-page 58 Selective Peripheral Module Control Idle mode allows users to substantially reduce power consumption by stopping the CPU clock. Even so, peripheral modules still remain clocked, and thus, consume power. There may be cases where the application needs what this mode does not provide: the allocation of power resources to the CPU processing with minimal power consumption from the peripherals. PIC18F87K90 family devices address this requirement by allowing peripheral modules to be selectively disabled, reducing or eliminating their power consumption. This can be done with two control bits: • Peripheral Enable bit, generically named XXXEN – Located in the respective module’s main Control register • Peripheral Module Disable (PMD) bit, generically named XXXMD – Located in one of the PMDx Control registers (PMD0, PMD1, PMD2 or PMD3) Disabling a module by clearing its XXXEN bit disables the module’s functionality, but leaves its registers available to be read and written to. This reduces power consumption, but not by as much as the second approach. Most peripheral modules have an enable bit. In contrast, setting the PMD bit for a module disables all clock sources to that module, reducing its power consumption to an absolute minimum. In this state, the control and status registers associated with the peripheral are also disabled, so writes to those registers have no effect and read values are invalid. Many peripheral modules have a corresponding PMD bit. There are four PMD registers in PIC18F87K90 family devices: PMD0, PMD1, PMD2 and PMD3. These registers have bits associated with each module for disabling or enabling a particular peripheral. Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY REGISTER 4-1: R/W-0 (1) CCP10MD PMD3: PERIPHERAL MODULE DISABLE REGISTER 3 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 CCP9MD(1) CCP8MD CCP7MD CCP6MD CCP5MD CCP4MD TMR12MD(1) bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 CCP10MD: PMD CCP10 Enable/Disable bit(1) 1 = Peripheral Module Disable (PMD) is enabled for CCP10, disabling all of its clock sources 0 = PMD is disabled for CCP10 bit 6 CCP9MD: PMD CCP9 Enable/Disable bit(1) 1 = Peripheral Module Disable (PMD) is enabled for CCP9, disabling all of its clock sources 0 = PMD is disabled for CCP9 bit 5 CCP8MD: PMD CCP8 Enable/Disable bit 1 = Peripheral Module Disable (PMD) is enabled for CCP8, disabling all of its clock sources 0 = PMD is disabled for CCP8 bit 4 CCP7MD: PMD CCP7 Enable/Disable bit 1 = Peripheral Module Disable (PMD) is enabled for CCP7, disabling all of its clock sources 0 = PMD is disabled for CCP7 bit 3 CCP6MD: PMD CCP6 Enable/Disable bit 1 = Peripheral Module Disable (PMD) is enabled for CCP6, disabling all of its clock sources 0 = PMD is disabled for CCP6 bit 2 CCP5MD: PMD CCP5 Enable/Disable bit 1 = Peripheral Module Disable (PMD) is enabled for CCP5, disabling all of its clock sources 0 = PMD is disabled for CCP5 bit 1 CCP4MD: PMD CCP4 Enable/Disable bit 1 = Peripheral Module Disable (PMD) is enabled for CCP4, disabling all of its clock sources 0 = PMD is disabled for CCP4 bit 0 TMR12MD: TMR12MD Disable bit(1) 1 = PMD is enabled and all TMR12MD clock sources are disabled 0 = PMD is disabled and TMR12MD is enabled Note 1: Unimplemented on devices with a program memory of 32 Kbytes (PIC18FX5K90). 2010 Microchip Technology Inc. Preliminary DS39957B-page 59 PIC18F87K90 FAMILY REGISTER 4-2: PMD2: PERIPHERAL MODULE DISABLE REGISTER 2 R/W-0 (1) TMR10MD R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 TMR8MD TMR7MD(1) TMR6MD TMR5MD CMP3MD CMP2MD CMP1MD bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 TMR10MD: TMR10MD Disable bit(1) 1 = Peripheral Module Disable (PMD) is enabled and all TMR10MD clock sources are disabled 0 = PMD is disabled and TMR10MD is enabled bit 6 TMR8MD: TMR8MD Disable bit 1 = PMD is enabled and all TMR8MD clock sources are disabled 0 = PMD is disabled and TMR8MD is enabled bit 5 TMR7MD: TMR7MD Disable bit(1) 1 = PMD is enabled and all TMR7MD clock sources are disabled 0 = PMD is disabled and TMR7MD is enabled bit 4 TMR6MD: TMR6MD Disable bit 1 = PMD is enabled and all TMR6MD clock sources are disabled 0 = PMD is disabled and TMR6MD is enabled bit 3 TMR5MD: TMR5MD Disable bit 1 = PMD is enabled and all TMR5MD clock sources are disabled 0 = PMD is disabled and TMR5MD is enabled bit 2 CMP3MD: PMD Comparator 3 Enable/Disable bit 1 = PMD is enabled for Comparator 3, disabling all of its clock sources 0 = PMD is disabled for Comparator 3 bit 1 CMP2MD: PMD Comparator 3 Enable/Disable bit 1 = PMD is enabled for Comparator 2, disabling all of its clock sources 0 = PMD is disabled for Comparator 2 bit 0 CMP1MD: PMD Comparator 3 Enable/Disable bit 1 = PMD is enabled for Comparator 1, disabling all of its clock sources 0 = PMD is disabled for Comparator 1 Note 1: Unimplemented on devices with a program memory of 32 Kbytes (PIC18FX5K90). DS39957B-page 60 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY REGISTER 4-3: PMD1: PERIPHERAL MODULE DISABLE REGISTER 1 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 — CTMUMD RTCCMD(1) TMR4MD TMR3MD TMR2MD TMR1MD — bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 Unimplemented: Read as ‘0’ bit 6 CTMUMD: PMD CTMU Enable/Disable bit 1 = Peripheral Module Disable (PMD) is enabled for CMTU, disabling all of its clock sources 0 = PMD is disabled for CMTU bit 5 RTCCMD: PMD RTCC Enable/Disable bit(1) 1 = PMD is enabled for RTCC, disabling all of its clock sources 0 = PMD is disabled for RTCC bit 4 TMR4MD: TMR4MD Disable bit 1 = PMD is enabled and all TMR4MD clock sources are disabled 0 = PMD is disabled and TMR4MD is enabled bit 3 TMR3MD: TMR3MD Disable bit 1 = PMD is enabled and all TMR3MD clock sources are disabled 0 = PMD is disabled and TMR3MD is enabled bit 2 TMR2MD: TMR2MD Disable bit 1 = PMD is enabled and all TMR2MD clock sources are disabled 0 = PMD is disabled and TMR2MD is enabled bit 1 TMR1MD: TMR1MD Disable bit 1 = PMD is enabled and all TMR1MD clock sources are disabled 0 = PMD is disabled and TMR1MD is enabled bit 0 Unimplemented: Read as ‘0’ Note 1: RTCCMD can only be set to ‘1’ after an EECON2 unlock sequence; refer to Section 17.0 “Real-Time Clock and Calendar (RTCC)” for the unlock sequence (see Example 17-1). 2010 Microchip Technology Inc. Preliminary DS39957B-page 61 PIC18F87K90 FAMILY REGISTER 4-4: PMD0: PERIPHERAL MODULE DISABLE REGISTER 0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 CCP3MD CCP2MD CCP1MD UART2MD UART1MD SSP2MD SSP1MD ADCMD bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 CCP3MD: PMD ECCP3 Enable/Disable bit 1 = Peripheral Module Disable (PMD) is enabled for ECCP3, disabling all of its clock sources 0 = PMD is disabled for ECCP3 bit 6 CCP2MD: PMD ECCP2 Enable/Disable bit 1 = PMD is enabled for ECCP2, disabling all of its clock sources 0 = PMD is disabled for ECCP2 bit 5 CCP1MD: PMD ECCP1 Enable/Disable bit 1 = PMD is enabled for ECCP1, disabling all of its clock sources 0 = PMD is disabled for ECCP1 bit 4 UART2MD: PMD UART2 Enable/Disable bit 1 = PMD is enabled for UART2, disabling all of its clock sources 0 = PMD is disabled for UART2 bit 3 UART1MD: PMD UART1 Enable/Disable bit 1 = PMD is enabled for UART1, disabling all of its clock sources 0 = PMD is disabled for UART1 bit 2 SSP2MD: PMD MSSP2 Enable/Disable bit 1 = PMD is enabled for MSSP2, disabling all of its clock sources 0 = PMD is disabled for MSSP2 bit 1 SSP1MD: PMD MSSP1 Enable/Disable bit 1 = PMD is enabled for MSSP1, disabling all of its clock sources 0 = PMD is disabled for MSSP1 bit 0 ADCMD: PMD Analog/Digital Converter PMD Enable/Disable bit 1 = PMD is enabled for Analog/Digital Converter, disabling all of its clock sources 0 = PMD is disabled for Analog/Digital Converter DS39957B-page 62 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 4.6 Exiting Idle and Sleep Modes 4.6.3 An exit from Sleep mode or any of the Idle modes is triggered by an interrupt, a Reset or a WDT time-out. This section discusses the triggers that cause exits from power-managed modes. The clocking subsystem actions are discussed in each of the power-managed modes (see Section 4.2 “Run Modes”, Section 4.3 “Sleep Mode” and Section 4.4 “Idle Modes”). 4.6.1 EXIT BY INTERRUPT Any of the available interrupt sources can cause the device to exit from an Idle or Sleep mode to a Run mode. To enable this functionality, an interrupt source must be enabled by setting its enable bit in one of the INTCONx or PIEx registers. The exit sequence is initiated when the corresponding interrupt flag bit is set. On all exits from Idle or Sleep modes by interrupt, code execution branches to the interrupt vector if the GIE/ GIEH bit (INTCON<7>) is set. Otherwise, code execution continues or resumes without branching (see Section 10.0 “Interrupts”). 4.6.2 EXIT BY WDT TIME-OUT A WDT time-out will cause different actions depending on which power-managed mode the device is in when the time-out occurs. If the device is not executing code (all Idle modes and Sleep mode), the time-out will result in an exit from the power-managed mode (see Section 4.2 “Run Modes” and Section 4.3 “Sleep Mode”). If the device is executing code (all Run modes), the time-out will result in a WDT Reset (see Section 28.2 “Watchdog Timer (WDT)”). Executing a SLEEP or CLRWDT instruction clears the WDT timer and postscaler, loses the currently selected clock source (if the Fail-Safe Clock Monitor is enabled) and modifies the IRCF bits in the OSCCON register (if the internal oscillator block is the device clock source). 2010 Microchip Technology Inc. EXIT BY RESET Normally, the device is held in Reset by the Oscillator Start-up Timer (OST) until the primary clock becomes ready. At that time, the OSTS bit is set and the device begins executing code. If the internal oscillator block is the new clock source, the HFIOFS/MFIOFS bits are set instead. The exit delay time from Reset to the start of code execution depends on both the clock sources before and after the wake-up, and the type of oscillator if the new clock source is the primary clock. Exit delays are summarized in Table 4-4. Code execution can begin before the primary clock becomes ready. If either the Two-Speed Start-up (see Section 28.4 “Two-Speed Start-up”) or Fail-Safe Clock Monitor (see Section 28.5 “Fail-Safe Clock Monitor”) is enabled, the device may begin execution as soon as the Reset source has cleared. Execution is clocked by the INTOSC multiplexer driven by the internal oscillator block. Execution is clocked by the internal oscillator block until either the primary clock becomes ready or a power-managed mode is entered before the primary clock becomes ready; the primary clock is then shut down. 4.6.4 EXIT WITHOUT AN OSCILLATOR START-UP DELAY Certain exits from power-managed modes do not invoke the OST at all. The two cases are: • When in PRI_IDLE mode, where the primary clock source is not stopped • When the primary clock source is not any of the LP, XT, HS or HSPLL modes In these instances, the primary clock source either does not require an oscillator start-up delay, since it is already running (PRI_IDLE), or normally does not require an oscillator start-up delay (RC, EC and INTIO Oscillator modes). However, a fixed delay of interval, TCSD, following the wake event is still required when leaving Sleep and Idle modes to allow the CPU to prepare for execution. Instruction execution resumes on the first clock cycle following this delay. Preliminary DS39957B-page 63 PIC18F87K90 FAMILY 4.7 Ultra Low-Power Wake-up The Ultra Low-Power Wake-up (ULPWU) on pin, RA0, allows a slow falling voltage to generate an interrupt without excess current consumption. FIGURE 4-9: To use this feature: 1. 2. 3. 4. 5. A series resistor, between RA0 and the external capacitor, provides overcurrent protection for the RA0/AN0/ ULPWU pin and enables software calibration of the time-out (see Figure 4-9). Charge the capacitor on RA0 by configuring the RA0 pin to an output and setting it to ‘1’. Stop charging the capacitor by configuring RA0 as an input. Discharge the capacitor by setting the ULPEN and ULPSINK bits in the WDTCON register. Configure Sleep mode. Enter Sleep mode. ULTRA LOW-POWER WAKE-UP INITIALIZATION RA0/AN0/ULPWU When the voltage on RA0 drops below VIL, the device wakes up and executes the next instruction. This feature provides a low-power technique for periodically waking up the device from Sleep mode. The time-out is dependent on the discharge time of the RC circuit on RA0. When the ULPWU module wakes the device from Sleep mode, the ULPLVL bit (WDTCON<5>) is set. Software can check this bit upon wake-up to determine the wake-up source. See Example 4-1 for initializing the ULPWU module. EXAMPLE 4-1: ULTRA LOW-POWER WAKE-UP INITIALIZATION A timer can be used to measure the charge time and discharge time of the capacitor. The charge time can then be adjusted to provide the desired delay in Sleep. This technique compensates for the affects of temperature, voltage and component accuracy. The peripheral can also be configured as a simple programmable Low-Voltage Detect (LVD) or temperature sensor. Note: //*************************** //Charge the capacitor on RA0 //*************************** TRISAbits.TRISA0 = 0; PORTAbits.RA0 = 1; for(i = 0; i < 10000; i++) Nop(); //***************************** //Stop Charging the capacitor //on RA0 //***************************** TRISAbits.TRISA0 = 1; //***************************** //Enable the Ultra Low Power //Wakeup module and allow //capacitor discharge //***************************** WDTCONbits.ULPEN = 1; WDTCONbits.ULPSINK = 1; //For Sleep OSCCONbits.IDLEN = 0; //Enter Sleep Mode // Sleep(); //for sleep, execution will //resume here DS39957B-page 64 Preliminary For more information, see AN 879, “Using the Microchip Ultra Low-Power Wake-up Module” (DS00879). 2010 Microchip Technology Inc. PIC18F87K90 FAMILY TABLE 4-4: EXIT DELAY ON WAKE-UP BY RESET FROM SLEEP MODE OR ANY IDLE MODE (BY CLOCK SOURCES) Power-Managed Mode Clock Source(5) Exit Delay Clock Ready Status Bits LP, XT, HS HSPLL PRI_IDLE mode EC, RC HF-INTOSC(2) OSTS TCSD(1) MF-INTOSC(2) LF-INTOSC SEC_IDLE mode SOSC None TCSD(1) SOSCRUN TCSD(1) MFIOFS HF-INTOSC(2) RC_IDLE mode MF-INTOSC(2) HFIOFS LF-INTOSC Sleep mode TOST(3) HSPLL TOST + trc(3) EC, RC TCSD(1) HF-INTOSC(2) LF-INTOSC Note 1: 2: 3: 4: 5: None LP, XT, HS MF-INTOSC(2) HFIOFS MFIOFS OSTS HFIOFS TIOBST(4) MFIOFS None TCSD (parameter 38, Table 31-10) is a required delay when waking from Sleep and all Idle modes, and runs concurrently with any other required delays (see Section 4.4 “Idle Modes”). Includes postscaler derived frequencies. On Reset, INTOSC defaults to HF-INTOSC at 8 MHz. TOST is the Oscillator Start-up Timer (parameter 32, Table 31-10). TRC is the PLL Lock-out Timer (parameter F12, Table 31-7); it is also designated as TPLL. Execution continues during TIOBST (parameter 39, Table 31-10), the INTOSC stabilization period. The clock source is dependent upon the settings of the SCS (OSCCON<1:0>), IRCF (OSCCON<6:4>) and FOSC (CONFIG1H<3:0>) bits. 2010 Microchip Technology Inc. Preliminary DS39957B-page 65 PIC18F87K90 FAMILY NOTES: DS39957B-page 66 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 5.0 RESET The PIC18F87K90 family of devices differentiates between various kinds of Reset: a) b) c) d) e) f) g) h) i) Power-on Reset (POR) MCLR Reset during normal operation MCLR Reset during power-managed modes Watchdog Timer (WDT) Reset (during execution) Configuration Mismatch (CM) Reset Brown-out Reset (BOR) RESET Instruction Stack Full Reset Stack Underflow Reset 5.1 RCON Register Device Reset events are tracked through the RCON register (Register 5-1). The lower five bits of the register indicate that a specific Reset event has occurred. In most cases, these bits can only be set by the event and must be cleared by the application after the event. The state of these flag bits, taken together, can be read to indicate the type of Reset that just occurred. This is described in more detail in Section 5.7 “Reset State of Registers”. This section discusses Resets generated by MCLR, POR and BOR, and covers the operation of the various start-up timers. Stack Reset events are covered in Section 6.1.3.4 “Stack Full and Underflow Resets”. WDT Resets are covered in Section 28.2 “Watchdog Timer (WDT)”. FIGURE 5-1: A simplified block diagram of the on-chip Reset circuit is shown in Figure 5-1. The RCON register also has a control bit for setting interrupt priority (IPEN). Interrupt priority is discussed in Section 10.0 “Interrupts”. SIMPLIFIED BLOCK DIAGRAM OF ON-CHIP RESET CIRCUIT RESET Instruction Configuration Word Mismatch Stack Pointer Stack Full/Underflow Reset External Reset MCLR ( )_IDLE Sleep WDT Time-out VDD Rise Detect VDD POR Pulse Brown-out Reset S PWRT 32 s PWRT LF-INTOSC 2010 Microchip Technology Inc. 66 ms R 11-Bit Ripple Counter Preliminary Q Chip_Reset DS39957B-page 67 PIC18F87K90 FAMILY REGISTER 5-1: RCON: RESET CONTROL REGISTER R/W-0 R/W-1 R/W-1 R/W-1 R-1 R-1 R/W-0 R/W-0 IPEN SBOREN CM RI TO PD POR BOR bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 IPEN: Interrupt Priority Enable bit 1 = Enable priority levels on interrupts 0 = Disable priority levels on interrupts (PIC16CXXX Compatibility mode) bit 6 SBOREN: BOR Software Enable bit If BOREN<1:0> = 01: 1 = BOR is enabled 0 = BOR is disabled If BOREN<1:0> = 00, 10 or 11: Bit is disabled and read as ‘0’. bit 5 CM: Configuration Mismatch Flag bit 1 = A Configuration Mismatch Reset has not occurred 0 = A Configuration Mismatch Reset has occurred (must be set in software after a Configuration Mismatch Reset occurs) bit 4 RI: RESET Instruction Flag bit 1 = The RESET instruction was not executed (set by firmware only) 0 = The RESET instruction was executed, causing a device Reset (must be set in software after a Brown-out Reset occurs) bit 3 TO: Watchdog Time-out Flag bit 1 = Set by power-up, CLRWDT instruction or SLEEP instruction 0 = A WDT time-out has occurred bit 2 PD: Power-Down Detection Flag bit 1 = Set by power-up or by the CLRWDT instruction 0 = Set by execution of the SLEEP instruction bit 1 POR: Power-on Reset Status bit 1 = A Power-on Reset has not occurred (set by firmware only) 0 = A Power-on Reset has occurred (must be set in software after a Power-on Reset occurs) bit 0 BOR: Brown-out Reset Status bit 1 = A Brown-out Reset has not occurred (set by firmware only) 0 = A Brown-out Reset has occurred (must be set in software after a Brown-out Reset occurs) Note 1: It is recommended that the POR bit be set after a Power-on Reset has been detected, so that subsequent Power-on Resets may be detected. 2: Brown-out Reset is said to have occurred when BOR is ‘0’ and POR is ‘1’ (assuming that POR was set to ‘1’ by software immediately after a Power-on Reset). DS39957B-page 68 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 5.2 Master Clear (MCLR) The MCLR pin provides a method for triggering a hard external Reset of the device. A Reset is generated by holding the pin low. PIC18 extended microcontroller devices have a noise filter in the MCLR Reset path which detects and ignores small pulses. The MCLR pin is not driven low by any internal Resets, including the WDT. 5.3 Power-on Reset (POR) A Power-on Reset condition is generated on-chip whenever VDD rises above a certain threshold. This allows the device to start in the initialized state when VDD is adequate for operation. To take advantage of the POR circuitry, tie the MCLR pin through a resistor (1 k to 10 k) to VDD. This will eliminate external RC components usually needed to create a Power-on Reset delay. A minimum rise rate for VDD is specified (parameter D004). For a slow rise time, see Figure 5-2. When the device starts normal operation (exiting the Reset condition), device operating parameters (such as voltage, frequency and temperature) must be met to ensure operation. If these conditions are not met, the device must be held in Reset until the operating conditions are met. Power-on Reset events are captured by the POR bit (RCON<1>). The state of the bit is set to ‘0’ whenever a Power-on Reset occurs and does not change for any other Reset event. POR is not reset to ‘1’ by any hardware event. To capture multiple events, the user manually resets the bit to ‘1’ in software following any Power-on Reset. 5.4 In Zero-Power BOR (ZPBORMV), the module monitors the VDD voltage and re-arms the POR at about 2V. ZPBORMV does not cause a Reset, but re-arms the POR. The BOR accuracy varies with its power level. The lower the power setting, the less accurate the BOR trip levels are. So, the high-power BOR has the highest accuracy and the low-power has the lowest accuracy. The trip levels (BVDD, parameter D005), current consumption (Section 31.2 “DC Characteristics: Power-Down and Supply Current PIC18F87K90 Family (Industrial)”) and time required below BVDD (TBOR, parameter 35) can all be found in Section 31.0 “Electrical Characteristics” FIGURE 5-2: D MCLR C 2010 Microchip Technology Inc. PIC18F87K90 Note 1: External Power-on Reset circuit is required only if the VDD power-up slope is too slow. The diode, D, helps discharge the capacitor quickly when VDD powers down. 2: R < 40 k is recommended to make sure that the voltage drop across R does not violate the device’s electrical specification. 3: R1 1 k will limit any current flowing into MCLR from external capacitor, C, in the event of MCLR/VPP pin breakdown, due to Electrostatic Discharge (ESD) or Electrical Overstress (EOS). 5.4.1 Each power mode is selected by the BORPWR<1:0> setting (CONFIG2L<6:5>). For low, medium and highpower BOR, the module monitors the VDD depending on the BORV<1:0> setting (CONFIG1L<3:2>). A BOR event re-arms the Power-on Reset. It also causes a Reset depending on which of the trip levels has been set: 1.8V, 2V, 2.7V or 3V. The typical (IBOR) for the Low and Medium Power BOR will be 0.75 A and 3 A. R R1 Brown-out Reset (BOR) High-Power BOR Medium Power BOR Low-Power BOR Zero-Power BOR VDD VDD The PIC18F87K90 family has four BOR modes: • • • • EXTERNAL POWER-ON RESET CIRCUIT (FOR SLOW VDD POWER-UP) DETECTING BOR The BOR bit always resets to ‘0’ on any Brown-out Reset or Power-on Reset event. This makes it difficult to determine if a Brown-out Reset event has occurred just by reading the state of BOR alone. A more reliable method is to simultaneously check the state of both POR and BOR. This assumes that the POR bit is reset to ‘1’ in software immediately after any Power-on Reset event. If BOR is ‘0’ while POR is ‘1’, it can be reliably assumed that a Brown-out Reset event has occurred. LP-BOR cannot be detected with the BOR bit in the RCON register. LP-BOR can rearm the POR and can cause a Power-on Reset. Preliminary DS39957B-page 69 PIC18F87K90 FAMILY 5.5 Configuration Mismatch (CM) 5.6 Power-up Timer (PWRT) The Configuration Mismatch (CM) Reset is designed to detect, and attempt to recover from, random, memory corrupting events. These include Electrostatic Discharge (ESD) events that can cause widespread, single bit changes throughout the device and result in catastrophic failure. PIC18F87K90 family devices incorporate an on-chip Power-up Timer (PWRT) to help regulate the Power-on Reset process. The PWRT is enabled by setting the PWRTEN bit (CONFIG2L<0>). The main function is to ensure that the device voltage is stable before code is executed. In PIC18F87K90 family Flash devices, the device Configuration registers (located in the configuration memory space) are continuously monitored during operation by comparing their values to complimentary shadow registers. If a mismatch is detected between the two sets of registers, a CM Reset automatically occurs. These events are captured by the CM bit (RCON<5>). The state of the bit is set to ‘0’ whenever a CM event occurs and does not change for any other Reset event. The Power-up Timer (PWRT) of the PIC18F87K90 family devices is a 13-bit counter that uses the LF-INTOSC source as the clock input. This yields an approximate time interval of 2,048 x 32 s = 66 ms. While the PWRT is counting, the device is held in Reset. A CM Reset behaves similarly to a Master Clear Reset, RESET instruction, WDT time-out or Stack Event Reset. As with all hard and power Reset events, the device Configuration Words are reloaded from the Flash Configuration Words in program memory as the device restarts. The power-up time delay depends on the LF-INTOSC clock and will vary from chip-to-chip due to temperature and process variation. See DC parameter 33 for details. 5.6.1 TIME-OUT SEQUENCE If enabled, the PWRT time-out is invoked after the POR pulse has cleared. The total time-out will vary based on the status of the PWRT. Figure 5-3, Figure 5-4, Figure 5-5 and Figure 5-6 all depict time-out sequences on power-up with the Power-up Timer enabled. Since the time-outs occur from the POR pulse, if MCLR is kept low long enough, the PWRT will expire. Bringing MCLR high will begin execution immediately (Figure 5-5). This is useful for testing purposes, or for synchronizing more than one PIC18 device operating in parallel. FIGURE 5-3: TIME-OUT SEQUENCE ON POWER-UP (MCLR TIED TO VDD, VDD RISE < TPWRT) VDD MCLR INTERNAL POR TPWRT PWRT TIME-OUT INTERNAL RESET DS39957B-page 70 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY FIGURE 5-4: TIME-OUT SEQUENCE ON POWER-UP (MCLR NOT TIED TO VDD): CASE 1 VDD MCLR INTERNAL POR TPWRT PWRT TIME-OUT INTERNAL RESET TIME-OUT SEQUENCE ON POWER-UP (MCLR NOT TIED TO VDD): CASE 2 FIGURE 5-5: VDD MCLR INTERNAL POR TPWRT PWRT TIME-OUT INTERNAL RESET FIGURE 5-6: SLOW RISE TIME (MCLR TIED TO VDD, VDD RISE > TPWRT) 3.3V VDD 0V 1V MCLR INTERNAL POR TPWRT PWRT TIME-OUT INTERNAL RESET 2010 Microchip Technology Inc. Preliminary DS39957B-page 71 PIC18F87K90 FAMILY 5.7 Reset State of Registers different Reset situations, as indicated in Table 5-1. These bits are used in software to determine the nature of the Reset. Most registers are unaffected by a Reset. Their status is unknown on POR and unchanged by all other Resets. The other registers are forced to a “Reset state” depending on the type of Reset that occurred. Table 5-2 describes the Reset states for all of the Special Function Registers. These are categorized by Power-on and Brown-out Resets, Master Clear and WDT Resets, and WDT wake-ups. Most registers are not affected by a WDT wake-up, since this is viewed as the resumption of normal operation. Status bits from the RCON register (CM, RI, TO, PD, POR and BOR) are set or cleared differently in TABLE 5-1: STATUS BITS, THEIR SIGNIFICANCE AND THE INITIALIZATION CONDITION FOR RCON REGISTER RCON Register STKPTR Register Program Counter(1) CM RI TO PD POR BOR STKFUL STKUNF Power-on Reset 0000h 1 1 1 1 0 0 0 0 RESET instruction 0000h u 0 u u u u u u Brown-out Reset 0000h 1 1 1 1 u 0 u u Configuration Mismatch Reset 0000h 0 u u u u u u u MCLR Reset during power-managed Run modes 0000h u u 1 u u u u u MCLR Reset during powermanaged Idle modes and Sleep mode 0000h u u 1 0 u u u u MCLR Reset during full-power execution 0000h u u u u u u u u Stack Full Reset (STVREN = 1) 0000h u u u u u u 1 u Stack Underflow Reset (STVREN = 1) 0000h u u u u u u u 1 Stack Underflow Error (not an actual Reset, STVREN = 0) 0000h u u u u u u u 1 WDT time-out during full-power or power-managed Run modes 0000h u u 0 u u u u u WDT time-out during power-managed Idle or Sleep modes PC + 2 u u 0 0 u u u u Interrupt exit from power-managed modes PC + 2 u u u 0 u u u u Condition Legend: u = unchanged Note 1: When the wake-up is due to an interrupt and the GIEH or GIEL bit is set, the PC is loaded with the interrupt vector (0008h or 0018h). DS39957B-page 72 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY TABLE 5-2: INITIALIZATION CONDITIONS FOR ALL REGISTERS Applicable Devices Power-on Reset, Brown-out Reset MCLR Resets, WDT Reset, RESET Instruction, Stack Resets, CM Resets TOSU PIC18F6XK90 PIC18F8XK90 ---0 0000 ---0 0000 ---0 uuuu(1) TOSH PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu(1) TOSL PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu(1) STKPTR PIC18F6XK90 PIC18F8XK90 00-0 0000 uu-0 0000 uu-u uuuu(1) PCLATU PIC18F6XK90 PIC18F8XK90 ---0 0000 ---0 0000 ---u uuuu PCLATH PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu PCL PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 PC + 2(2) TBLPTRU PIC18F6XK90 PIC18F8XK90 --00 0000 --00 0000 --uu uuuu TBLPTRH PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu TBLPTRL PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu TABLAT PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu PRODH PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu PRODL PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu INTCON PIC18F6XK90 PIC18F8XK90 0000 000x 0000 000u uuuu uuuu(3) INTCON2 PIC18F6XK90 PIC18F8XK90 1111 1111 1111 1111 uuuu uuuu(3) INTCON3 PIC18F6XK90 PIC18F8XK90 1100 0000 1100 0000 uuuu uuuu(3) INDF0 PIC18F6XK90 PIC18F8XK90 N/A N/A N/A Register Wake-up via WDT or Interrupt POSTINC0 PIC18F6XK90 PIC18F8XK90 N/A N/A N/A POSTDEC0 PIC18F6XK90 PIC18F8XK90 N/A N/A N/A PREINC0 PIC18F6XK90 PIC18F8XK90 N/A N/A N/A PLUSW0 PIC18F6XK90 PIC18F8XK90 N/A N/A N/A FSR0H PIC18F6XK90 PIC18F8XK90 ---- xxx ---- uuuu ---- uuuu FSR0L PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu WREG PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu INDF1 PIC18F6XK90 PIC18F8XK90 N/A N/A N/A POSTINC1 PIC18F6XK90 PIC18F8XK90 N/A N/A N/A POSTDEC1 PIC18F6XK90 PIC18F8XK90 N/A N/A N/A PREINC1 PIC18F6XK90 PIC18F8XK90 N/A N/A N/A PLUSW1 PIC18F6XK90 PIC18F8XK90 N/A N/A N/A FSR1H PIC18F6XK90 PIC18F8XK90 ---- xxxx ---- uuuu ---- uuuu FSR1L PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu BSR PIC18F6XK90 PIC18F8XK90 ---- 0000 ---- 0000 ---- uuuu Legend: u = unchanged, x = unknown, - = unimplemented bit, read as ‘0’, q = value depends on condition. Shaded cells indicate conditions do not apply for the designated device. Note 1: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the TOSU, TOSH and TOSL are updated with the current value of the PC. The STKPTR is modified to point to the next location in the hardware stack. 2: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the PC is loaded with the interrupt vector (0008h or 0018h). 3: One or more bits in the INTCONx or PIRx registers will be affected (to cause wake-up). 4: See Table 5-1 for Reset value for specific condition. 2010 Microchip Technology Inc. Preliminary DS39957B-page 73 PIC18F87K90 FAMILY TABLE 5-2: INITIALIZATION CONDITIONS FOR ALL REGISTERS (CONTINUED) Applicable Devices Power-on Reset, Brown-out Reset MCLR Resets, WDT Reset, RESET Instruction, Stack Resets, CM Resets PIC18F6XK90 PIC18F8XK90 N/A N/A Register INDF2 Wake-up via WDT or Interrupt N/A POSTINC2 PIC18F6XK90 PIC18F8XK90 N/A N/A N/A POSTDEC2 PIC18F6XK90 PIC18F8XK90 N/A N/A N/A PREINC2 PIC18F6XK90 PIC18F8XK90 N/A N/A N/A PLUSW2 PIC18F6XK90 PIC18F8XK90 N/A N/A N/A FSR2H PIC18F6XK90 PIC18F8XK90 ---- xxxx ----uuuu ---- uuuu FSR2L PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu STATUS PIC18F6XK90 PIC18F8XK90 ---x xxxx ---u uuuu ---u uuuu TMR0H PIC18F6XK90 PIC18F8XK90 0000 0000 uuuu uuuu uuuu uuuu TMR0L PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu T0CON PIC18F6XK90 PIC18F8XK90 1111 1111 1111 1111 uuuu uuuu SPBRGH1 PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu OSCCON PIC18F6XK90 PIC18F8XK90 0110 q000 0110 q000 uuuu quuu IPR5 PIC18F6XK90 PIC18F8XK90 1111 1111 1111 1111 uuuu uuuu WDTCON PIC18F6XK90 PIC18F8XK90 0-x0 -000 0-x0 -000 u-uu -uuu RCON PIC18F6XK90 PIC18F8XK90 0111 11qq 0uqq qquu uuuu qquu TMR1H PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu TMR1L PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu T1CON PIC18F6XK90 PIC18F8XK90 0000 0000 uuuu uuuu uuuu uuuu TMR2 PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu PR2 PIC18F6XK90 PIC18F8XK90 1111 1111 1111 1111 uuuu uuuu T2CON PIC18F6XK90 PIC18F8XK90 -000 0000 -000 0000 -uuu uuuu SSP1BUF PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu SSP1ADD PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu SSP1STAT PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu SSP1CON1 PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu SSP1CON2 PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu ADRESH PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu ADRESL PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu ADCON0 PIC18F6XK90 PIC18F8XK90 -000 0000 -000 0000 -uuu uuuu ADCON1 PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu ADCON2 PIC18F6XK90 PIC18F8XK90 0-00 0000 0-00 0000 u-uu uuuu ECCP1AS PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu Legend: u = unchanged, x = unknown, - = unimplemented bit, read as ‘0’, q = value depends on condition. Shaded cells indicate conditions do not apply for the designated device. Note 1: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the TOSU, TOSH and TOSL are updated with the current value of the PC. The STKPTR is modified to point to the next location in the hardware stack. 2: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the PC is loaded with the interrupt vector (0008h or 0018h). 3: One or more bits in the INTCONx or PIRx registers will be affected (to cause wake-up). 4: See Table 5-1 for Reset value for specific condition. DS39957B-page 74 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY TABLE 5-2: INITIALIZATION CONDITIONS FOR ALL REGISTERS (CONTINUED) Applicable Devices Power-on Reset, Brown-out Reset MCLR Resets, WDT Reset, RESET Instruction, Stack Resets, CM Resets ECCP1DEL PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu CCPR1H PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu CCPR1L PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu CCP1CON PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu PIR5 PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu PIE5 PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu(1) IPR4 PIC18F6XK90 PIC18F8XK90 1111 1111 1111 1111 uuuu uuuu PIR4 PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu(1) PIE4 PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu CVRCON PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu CMSTAT PIC18F6XK90 PIC18F8XK90 111- ---- 111- ---- uuu- ---- TMR3H PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu TMR3L PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu T3CON PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0x00 0000 0x00 T3GCON PIC18F6XK90 PIC18F8XK90 0000 0x00 0000 0x00 uuuu uuuu SPBRG1 PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu RCREG1 PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu TXREG1 PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu TXSTA1 PIC18F6XK90 PIC18F8XK90 0000 0010 0000 0010 uuuu uuuu RCSTA1 PIC18F6XK90 PIC18F8XK90 0000 000x 0000 000x uuuu uuuu T1GCON PIC18F6XK90 PIC18F8XK90 0000 0x00 0000 0x00 uuuu uuuu IPR6 PIC18F6XK90 PIC18F8XK90 ---1 -111 ---1 -111 ---u -uuu HLVDCON PIC18F6XK90 PIC18F8XK90 0000 0101 0000 0101 uuuu uuuu PIR6 PIC18F6XK90 PIC18F8XK90 ---0 -000 ---0 -000 ---u -uuu IPR3 PIC18F6XK90 PIC18F8XK90 1111 1111 1111 1111 uuuu uuuu PIR3 PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu PIE3 PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu IPR2 PIC18F6XK90 PIC18F8XK90 1-11 1111 1-11 1111 u-uu uuuu PIR2 PIC18F6XK90 PIC18F8XK90 0-00 0000 0-00 0000 u-uu uuuu PIE2 PIC18F6XK90 PIC18F8XK90 0-00 0000 0-00 0000 u-uu uuuu IPR1 PIC18F6XK90 PIC18F8XK90 -111 1111 -111 1111 -uuu uuuu PIR1 PIC18F6XK90 PIC18F8XK90 -000 0000 -000 0000 -uuu uuuu PIE1 PIC18F6XK90 PIC18F8XK90 -000 0000 -000 0000 -uuu uuuu Register Wake-up via WDT or Interrupt Legend: u = unchanged, x = unknown, - = unimplemented bit, read as ‘0’, q = value depends on condition. Shaded cells indicate conditions do not apply for the designated device. Note 1: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the TOSU, TOSH and TOSL are updated with the current value of the PC. The STKPTR is modified to point to the next location in the hardware stack. 2: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the PC is loaded with the interrupt vector (0008h or 0018h). 3: One or more bits in the INTCONx or PIRx registers will be affected (to cause wake-up). 4: See Table 5-1 for Reset value for specific condition. 2010 Microchip Technology Inc. Preliminary DS39957B-page 75 PIC18F87K90 FAMILY TABLE 5-2: INITIALIZATION CONDITIONS FOR ALL REGISTERS (CONTINUED) Applicable Devices Power-on Reset, Brown-out Reset MCLR Resets, WDT Reset, RESET Instruction, Stack Resets, CM Resets PSTR1CON PIC18F6XK90 PIC18F8XK90 00-0 0001 00-0 0001 uu-u uuuu OSCTUNE PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu TRISJ PIC18F6XK90 PIC18F8XK90 1111 1111 1111 1111 uuuu uuuu TRISH PIC18F6XK90 PIC18F8XK90 1111 1111 1111 1111 uuuu uuuu TRISG PIC18F6XK90 PIC18F8XK90 ---1 1111 ---1 1111 ---u uuuu TRISF PIC18F6XK90 PIC18F8XK90 1111 111- 1111 111- uuuu uuu- TRISE PIC18F6XK90 PIC18F8XK90 1111 1111 1111 1111 uuuu uuuu TRISD PIC18F6XK90 PIC18F8XK90 1111 1111 1111 1111 uuuu uuuu TRISC PIC18F6XK90 PIC18F8XK90 1111 1111 1111 1111 uuuu uuuu TRISB PIC18F6XK90 PIC18F8XK90 1111 1111 1111 1111 uuuu uuuu TRISA PIC18F6XK90 PIC18F8XK90 1111 1111 1111 1111 uuuu uuuu LATJ PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu LATH PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu LATG PIC18F6XK90 PIC18F8XK90 ---x xxxx ---u uuuu ---u uuuu LATF PIC18F6XK90 PIC18F8XK90 xxxx xxx- uuuu uuu- uuuu uuu- LATE PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu LATD PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu LATC PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu LATB PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu LATA PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu PORTJ PIC18F6XK90 PIC18F8XK90 xxxx xxxx xxxx xxxx uuuu uuuu PORTH PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu PORTG PIC18F6XK90 PIC18F8XK90 --x0 000x --x0 000x --uu uuuu PORTF PIC18F6XK90 PIC18F8XK90 0000 000- 0000 000- uuuu uuu- PORTE PIC18F6XK90 PIC18F8XK90 xxxx xxxx xxxx xxxx uuuu uuuu PORTD PIC18F6XK90 PIC18F8XK90 xxxx xxxx xxxx xxxx uuuu uuuu PORTC PIC18F6XK90 PIC18F8XK90 xxxx xxxx xxxx xxxx uuuu uuuu PORTB PIC18F6XK90 PIC18F8XK90 xxxx xxxx xxxx xxxx uuuu uuuu PORTA PIC18F6XK90 PIC18F8XK90 xx0x 0000 uu0u 0000 uuuu uuuu Register Wake-up via WDT or Interrupt Legend: u = unchanged, x = unknown, - = unimplemented bit, read as ‘0’, q = value depends on condition. Shaded cells indicate conditions do not apply for the designated device. Note 1: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the TOSU, TOSH and TOSL are updated with the current value of the PC. The STKPTR is modified to point to the next location in the hardware stack. 2: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the PC is loaded with the interrupt vector (0008h or 0018h). 3: One or more bits in the INTCONx or PIRx registers will be affected (to cause wake-up). 4: See Table 5-1 for Reset value for specific condition. DS39957B-page 76 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY TABLE 5-2: INITIALIZATION CONDITIONS FOR ALL REGISTERS (CONTINUED) Applicable Devices Power-on Reset, Brown-out Reset MCLR Resets, WDT Reset, RESET Instruction, Stack Resets, CM Resets EECON1 PIC18F6XK90 PIC18F8XK90 xx-0 x000 uu-0 u000 EECON2 PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 0000 0000 LCDDATA23 PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu Register Wake-up via WDT or Interrupt uu-u uuuu LCDDATA22 PIC18F6XK90 PIC18F8XK90 ---- ---x ---- ---u ---- ---u LCDDATA22 PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu LCDDATA21 PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu LCDDATA20 PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu LCDDATA19 PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu LCDDATA18 PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu LCDDATA17 PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu LCDDATA16 PIC18F6XK90 PIC18F8XJ90 ---- ---x ---- ---u ---- ---u LCDDATA16 PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu LCDDATA15 PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu LCDDATA14 PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu LCDDATA13 PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu LCDDATA12 PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu LCDDATA11 PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu LCDDATA10 PIC18F6XK90 PIC18F8XK90 ---- ---x ---- ---u ---- ---u LCDDATA10 PIC18F6XK90 PIC18F8XJ90 xxxx xxxx uuuu uuuu uuuu uuuu LCDDATA9 PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu LCDDATA8 PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu LCDDATA7 PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu LCDDATA6 PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu LCDDATA5 PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu LCDDATA4 PIC18F6XK90 PIC18F8XJ90 ---- ---x ---- ---u ---- ---u LCDDATA4 PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu LCDDATA3 PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu LCDDATA2 PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu LCDDATA1 PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu LCDDATA0 PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu BAUDCON1 PIC18F6XK90 PIC18F8XK90 0100 0-00 0100 0-00 uuuu u-uu OSCCON2 PIC18F6XK90 PIC18F8XK90 -0-- 0-x0 -0-- 0-u0 -u-- u-uu EEADRH PIC18F6XK90 PIC18F8XK90 ---- --00 ---- --00 ---- --uu Legend: u = unchanged, x = unknown, - = unimplemented bit, read as ‘0’, q = value depends on condition. Shaded cells indicate conditions do not apply for the designated device. Note 1: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the TOSU, TOSH and TOSL are updated with the current value of the PC. The STKPTR is modified to point to the next location in the hardware stack. 2: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the PC is loaded with the interrupt vector (0008h or 0018h). 3: One or more bits in the INTCONx or PIRx registers will be affected (to cause wake-up). 4: See Table 5-1 for Reset value for specific condition. 2010 Microchip Technology Inc. Preliminary DS39957B-page 77 PIC18F87K90 FAMILY TABLE 5-2: INITIALIZATION CONDITIONS FOR ALL REGISTERS (CONTINUED) Applicable Devices Power-on Reset, Brown-out Reset MCLR Resets, WDT Reset, RESET Instruction, Stack Resets, CM Resets EEADR PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu EEDATA PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu PIE6 PIC18F6XK90 PIC18F8XK90 ---0 -000 ---0 -000 ---u -uuu RTCCFG PIC18F6XK90 PIC18F8XK90 0-00 0000 u-uu uuuu u-uu uuuu RTCCAL PIC18F6XK90 PIC18F8XK90 0000 0000 uuuu uuuu uuuu uuuu RTCVALH PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu RTCVALL PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu ALRMCFG PIC18F6XK90 PIC18F8XK90 0000 0000 uuuu uuuu uuuu uuuu ALRMRPT PIC18F6XK90 PIC18F8XK90 0000 0000 uuuu uuuu uuuu uuuu ALRMVALH PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu ALRMVALL PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu CTMUCONH PIC18F6XK90 PIC18F8XK90 0-00 0000 0-00 0000 u-uu uuuu CTMUCONL PIC18F6XK90 PIC18F8XK90 0000 0000 0000 00xx uuuu uuuu CTMUICON PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu CM1CON PIC18F6XK90 PIC18F8XK90 0001 1111 0001 1111 uuuu uuuu PADCFG1 PIC18F6XK90 PIC18F8XK90 000- -00- uuu- -uu- uuu- -uu- ECCP2AS PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu ECCP2DEL PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu CCPR2H PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu CCPR2L PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu CCP2CON PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu ECCP3AS PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu ECCP3DEL PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu CCPR3H PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu CCPR3L PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu CCP3CON PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu CCPR8H PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu CCPR8L PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu CCP8CON PIC18F6XK90 PIC18F8XK90 --00 0000 --00 0000 --uu uuuu CCPR9H PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu CCPR9L PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu CCP9CON PIC18F6XK90 PIC18F8XK90 --00 0000 --00 0000 --uu uuuu CCPR10H PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu Register Wake-up via WDT or Interrupt Legend: u = unchanged, x = unknown, - = unimplemented bit, read as ‘0’, q = value depends on condition. Shaded cells indicate conditions do not apply for the designated device. Note 1: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the TOSU, TOSH and TOSL are updated with the current value of the PC. The STKPTR is modified to point to the next location in the hardware stack. 2: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the PC is loaded with the interrupt vector (0008h or 0018h). 3: One or more bits in the INTCONx or PIRx registers will be affected (to cause wake-up). 4: See Table 5-1 for Reset value for specific condition. DS39957B-page 78 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY TABLE 5-2: INITIALIZATION CONDITIONS FOR ALL REGISTERS (CONTINUED) Applicable Devices Power-on Reset, Brown-out Reset MCLR Resets, WDT Reset, RESET Instruction, Stack Resets, CM Resets CCPR10L PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu CCP10CON PIC18F6XK90 PIC18F8XK90 --00 0000 --00 0000 --uu uuuu TMR7H PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu TMR7L PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu T7CON PIC18F6XK90 PIC18F8XK90 0000 0000 uuuu uuuu uuuu -uuu T7GCON PIC18F6XK90 PIC18F8XK90 0000 0x00 0000 0x00 uuuu uuuu TMR6 PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu PR6 PIC18F6XK90 PIC18F8XK90 1111 1111 1111 1111 uuuu uuuu T6CON PIC18F6XK90 PIC18F8XK90 -000 0000 -000 0000 -uuu uuuu TMR8 PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu PR8 PIC18F6XK90 PIC18F8XK90 1111 1111 1111 1111 uuuu uuuu T8CON PIC18F6XK90 PIC18F8XK90 -000 0000 -000 0000 -uuu uuuu TMR10 PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu PR10 PIC18F6XK90 PIC18F8XK90 1111 1111 1111 1111 uuuu uuuu T10CON PIC18F6XK90 PIC18F8XK90 -000 0000 -000 0000 -uuu uuuu TMR12 PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu PR12 PIC18F6XK90 PIC18F8XK90 1111 1111 1111 1111 uuuu uuuu Register Wake-up via WDT or Interrupt T12CON PIC18F6XK90 PIC18F8XK90 -000 0000 -000 0000 -uuu uuuu CM2CON PIC18F6XK90 PIC18F8XK90 0001 1111 0001 1111 uuuu uuuu CM3CON PIC18F6XK90 PIC18F8XK90 0001 1111 0001 1111 uuuu uuuu CCPTMRS0 PIC18F6XK90 PIC18F8XK90 0000 0000 uuuu uuuu uuuu uuuu CCPTMRS1 PIC18F6XK90 PIC18F8XK90 00-0 -000 uu-u -uuu uu-u -uuu CCPTMRS2 PIC18F6XK90 PIC18F8XK90 ---0 -000 ---u -uuu ---u -uuu REFOCON PIC18F6XK90 PIC18F8XK90 0-00 0000 u-uu uuuu u-uu uuuu ODCON1 PIC18F6XK90 PIC18F8XK90 000- ---0 uuu- ---u uuu- ---u ODCON2 PIC18F6XK90 PIC18F8XK90 0000 0000 uuuu uuuu uuuu uuuu ODCON3 PIC18F6XK90 PIC18F8XK90 00-- ---0 uu-- ---u uu-- ---u ANCON0 PIC18F6XK90 PIC18F8XK90 1111 1111 uuuu uuuu uuuu uuuu ANCON1 PIC18F6XK90 PIC18F8XK90 1111 1111 uuuu uuuu uuuu uuuu ANCON2 PIC18F6XK90 PIC18F8XK90 1111 1111 uuuu uuuu uuuu uuuu RCSTA2 PIC18F6XK90 PIC18F8XK90 0000 000x 0000 000x uuuu uuuu TXSTA2 PIC18F6XK90 PIC18F8XK90 0000 0010 0000 0010 uuuu uuuu BAUDCON2 PIC18F6XK90 PIC18F8XK90 0100 0-00 0100 0-00 uuuu u-uu Legend: u = unchanged, x = unknown, - = unimplemented bit, read as ‘0’, q = value depends on condition. Shaded cells indicate conditions do not apply for the designated device. Note 1: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the TOSU, TOSH and TOSL are updated with the current value of the PC. The STKPTR is modified to point to the next location in the hardware stack. 2: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the PC is loaded with the interrupt vector (0008h or 0018h). 3: One or more bits in the INTCONx or PIRx registers will be affected (to cause wake-up). 4: See Table 5-1 for Reset value for specific condition. 2010 Microchip Technology Inc. Preliminary DS39957B-page 79 PIC18F87K90 FAMILY TABLE 5-2: INITIALIZATION CONDITIONS FOR ALL REGISTERS (CONTINUED) Applicable Devices Power-on Reset, Brown-out Reset MCLR Resets, WDT Reset, RESET Instruction, Stack Resets, CM Resets SPBRGH2 PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu SPBRG2 PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu RCREG2 PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu TXREG2 PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu PSTR2CON PIC18F6XK90 PIC18F8XK90 00-0 0001 00-0 0001 uu-u uuuu PSTR3CON PIC18F6XK90 PIC18F8XK90 00-0 0001 00-0 0001 uu-u uuuu PMD0 PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu PMD1 PIC18F6XK90 PIC18F8XK90 -000 000- -000 000- -uuu uuu- PMD2 PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu PMD3 PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu TMR5H PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu TMR5L PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu T5CON PIC18F6XK90 PIC18F8XK90 0000 0000 uuuu uuuu uuuu uuuu T5GCON PIC18F6XK90 PIC18F8XK90 0000 0x00 0000 0x00 uuuu uuuu CCPR4H PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu CCPR4L PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu CCP4CON PIC18F6XK90 PIC18F8XK90 --00 0000 --00 0000 --uu uuuu CCPR5H PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu CCPR5L PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu CCP5CON PIC18F6XK90 PIC18F8XK90 --00 0000 --00 0000 --uu uuuu CCPR6H PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu CCPR6L PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu CCP6CON PIC18F6XK90 PIC18F8XK90 --00 0000 --00 0000 --uu uuuu CCPR7H PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu CCPR7L PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu CCP7CON PIC18F6XK90 PIC18F8XK90 --00 0000 --00 0000 --uu uuuu TMR4 PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu PR4 PIC18F6XK90 PIC18F8XK90 1111 1111 uuuu uuuu uuuu uuuu T4CON PIC18F6XK90 PIC18F8XK90 -000 0000 -000 0000 -uuu uuuu SSP2BUF PIC18F6XK90 PIC18F8XK90 xxxx xxxx uuuu uuuu uuuu uuuu SSP2ADD PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu SSP2STAT PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu SSP2CON1 PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu Register Wake-up via WDT or Interrupt Legend: u = unchanged, x = unknown, - = unimplemented bit, read as ‘0’, q = value depends on condition. Shaded cells indicate conditions do not apply for the designated device. Note 1: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the TOSU, TOSH and TOSL are updated with the current value of the PC. The STKPTR is modified to point to the next location in the hardware stack. 2: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the PC is loaded with the interrupt vector (0008h or 0018h). 3: One or more bits in the INTCONx or PIRx registers will be affected (to cause wake-up). 4: See Table 5-1 for Reset value for specific condition. DS39957B-page 80 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY TABLE 5-2: INITIALIZATION CONDITIONS FOR ALL REGISTERS (CONTINUED) Applicable Devices Power-on Reset, Brown-out Reset MCLR Resets, WDT Reset, RESET Instruction, Stack Resets, CM Resets PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu LCDREF PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu LCDRL PIC18F6XK90 PIC18F8XK90 0000 -000 0000 -000 uuuu -uuu Register SSP2CON2 Wake-up via WDT or Interrupt LCDSE5 PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu LCDSE4 PIC18F6XK90 PIC18F8XK90 ---- ---0 ---- ---u ---- ---u LCDSE4 PIC18F6XK90 PIC18F8XK90 0000 0000 uuuu uuuu uuuu uuuu LCDSE3 PIC18F6XK90 PIC18F8XK90 0000 0000 uuuu uuuu uuuu uuuu LCDSE2 PIC18F6XK90 PIC18F8XK90 0000 0000 uuuu uuuu uuuu uuuu LCDSE1 PIC18F6XK90 PIC18F8XK90 0000 0000 uuuu uuuu uuuu uuuu LCDSE0 PIC18F6XK90 PIC18F8XK90 0000 0000 uuuu uuuu uuuu uuuu LCDPS PIC18F6XK90 PIC18F8XK90 0000 0000 0000 0000 uuuu uuuu LCDCON PIC18F6XK90 PIC18F8XK90 000- 0000 000- 0000 uuu- uuuu Legend: u = unchanged, x = unknown, - = unimplemented bit, read as ‘0’, q = value depends on condition. Shaded cells indicate conditions do not apply for the designated device. Note 1: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the TOSU, TOSH and TOSL are updated with the current value of the PC. The STKPTR is modified to point to the next location in the hardware stack. 2: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the PC is loaded with the interrupt vector (0008h or 0018h). 3: One or more bits in the INTCONx or PIRx registers will be affected (to cause wake-up). 4: See Table 5-1 for Reset value for specific condition. 2010 Microchip Technology Inc. Preliminary DS39957B-page 81 PIC18F87K90 FAMILY NOTES: DS39957B-page 82 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 6.0 MEMORY ORGANIZATION PIC18F87K90 family devices have these types of memory: • Program Memory • Data RAM • Data EEPROM As Harvard architecture devices, the data and program memories use separate busses. This enables concurrent access of the two memory spaces. FIGURE 6-1: The data EEPROM, for practical purposes, can be regarded as a peripheral device because it is addressed and accessed through a set of control registers. Additional detailed information on the operation of the Flash program memory is provided in Section 7.0 “Flash Program Memory”. The data EEPROM is discussed separately in Section 8.0 “Data EEPROM Memory”. MEMORY MAPS FOR PIC18F87K90 FAMILY DEVICES PC<20:0> CALL, CALLW, RCALL, RETURN, RETFIE, RETLW, ADDULNK, SUBULNK 21 Stack Level 1 Stack Level 31 PIC18FX5K90 On-Chip Memory PIC18FX6K90 On-Chip Memory PIC18FX7K90 On-Chip Memory 000000h 007FFFh 01FFFFh Unimplemented Unimplemented Unimplemented Read as ‘0’ Read as ‘0’ Read as ‘0’ User Memory Space 00FFFFh 1FFFFFh Note: Sizes of memory areas are not to scale. Sizes of program memory areas are enhanced to show detail. 2010 Microchip Technology Inc. Preliminary DS39957B-page 83 PIC18F87K90 FAMILY 6.1 Program Memory Organization FIGURE 6-2: PIC18 microcontrollers implement a 21-bit program counter that is capable of addressing a 2-Mbyte program memory space. Accessing a location between the upper boundary of the physically implemented memory and the 2-Mbyte address will return all ‘0’s (a NOP instruction). The entire PIC18F87K90 family offers a range of on-chip Flash program memory sizes, from 32 Kbytes (up to 16,384 single-word instructions) to 128 Kbytes (65,536 single-word instructions). • PIC18F65K90 and PIC18F85K90 — 32 Kbytes of Flash memory, storing up to 16,384 single-word instructions • PIC18F66K90 and PIC18F86K90 — 64 Kbytes of Flash memory, storing up to 32,768 single-word instructions • PIC18F67K90 and PIC18F87K90 — 128 Kbytes of Flash memory, storing up to 65,536 single-word instructions The program memory maps for individual family members are shown in Figure 6-1. 6.1.1 Reset Vector 0000h High-Priority Interrupt Vector 0008h Low-Priority Interrupt Vector 0018h On-Chip Program Memory HARD MEMORY VECTORS Read ‘0’ All PIC18 devices have a total of three hard-coded return vectors in their program memory space. The Reset vector address is the default value to which the program counter returns on all device Resets. It is located at 0000h. PIC18 devices also have two interrupt vector addresses for handling high-priority and low-priority interrupts. The high-priority interrupt vector is located at 0008h and the low-priority interrupt vector is at 0018h. The locations of these vectors are shown, in relation to the program memory map, in Figure 6-2. DS39957B-page 84 HARD VECTOR FOR PIC18F87K90 FAMILY DEVICES 1FFFFFh Legend: Preliminary (Top of Memory) represents upper boundary of on-chip program memory space (see Figure 6-1 for device-specific values). Shaded area represents unimplemented memory. Areas are not shown to scale. 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 6.1.2 PROGRAM COUNTER The Program Counter (PC) specifies the address of the instruction to fetch for execution. The PC is 21 bits wide and contained in three separate 8-bit registers. The low byte, known as the PCL register, is both readable and writable. The high byte, or PCH register, contains the PC<15:8> bits and is not directly readable or writable. Updates to the PCH register are performed through the PCLATH register. The upper byte is called PCU. This register contains the PC<20:16> bits; it is also not directly readable or writable. Updates to the PCU register are performed through the PCLATU register. The contents of PCLATH and PCLATU are transferred to the program counter by any operation that writes PCL. Similarly, the upper two bytes of the program counter are transferred to PCLATH and PCLATU by an operation that reads PCL. This is useful for computed offsets to the PC (see Section 6.1.5.1 “Computed GOTO”). The PC addresses bytes in the program memory. To prevent the PC from becoming misaligned with word instructions, the Least Significant bit of PCL is fixed to a value of ‘0’. The PC increments by two to address sequential instructions in the program memory. The CALL, RCALL, GOTO and program branch instructions write to the program counter directly. For these instructions, the contents of PCLATH and PCLATU are not transferred to the program counter. 6.1.3 RETURN ADDRESS STACK The return address stack enables execution of any combination of up to 31 program calls and interrupts. The PC is pushed onto the stack when a CALL or RCALL instruction is executed, or an interrupt is Acknowledged. The PC value is pulled off the stack on a RETURN, RETLW or a RETFIE instruction. The value also is pulled off the stack on ADDULNK and SUBULNK instructions, if the extended instruction set is enabled. PCLATU and PCLATH are not affected by any of the RETURN or CALL instructions. FIGURE 6-3: The stack operates as a 31-word by 21-bit RAM and a 5-bit Stack Pointer, STKPTR. The stack space is not part of either program or data space. The Stack Pointer is readable and writable and the address on the top of the stack is readable and writable through the Top-of-Stack Special Function Registers. Data can also be pushed to, or popped from the stack, using these registers. A CALL type instruction causes a push onto the stack. The Stack Pointer is first incremented and the location pointed to by the Stack Pointer is written with the contents of the PC (already pointing to the instruction following the CALL). A RETURN type instruction causes a pop from the stack. The contents of the location pointed to by the STKPTR are transferred to the PC and then the Stack Pointer is decremented. The Stack Pointer is initialized to ‘00000’ after all Resets. There is no RAM associated with the location corresponding to a Stack Pointer value of ‘00000’; this is only a Reset value. Status bits indicate if the stack is full, has overflowed or has underflowed. 6.1.3.1 Top-of-Stack Access Only the top of the return address stack (TOS) is readable and writable. A set of three registers, TOSU:TOSH:TOSL, holds the contents of the stack location pointed to by the STKPTR register (Figure 6-3). This allows users to implement a software stack, if necessary. After a CALL, RCALL or interrupt (or ADDULNK and SUBULNK instructions, if the extended instruction set is enabled), the software can read the pushed value by reading the TOSU:TOSH:TOSL registers. These values can be placed on a user-defined software stack. At return time, the software can return these values to TOSU:TOSH:TOSL and do a return. While accessing the stack, users must disable the global interrupt enable bits to prevent inadvertent stack corruption. RETURN ADDRESS STACK AND ASSOCIATED REGISTERS Return Address Stack <20:0> Top-of-Stack Registers TOSU 00h TOSH 1Ah 11111 11110 11101 TOSL 34h Top-of-Stack 2010 Microchip Technology Inc. 001A34h 000D58h Preliminary Stack Pointer STKPTR<4:0> 00010 00011 00010 00001 00000 DS39957B-page 85 PIC18F87K90 FAMILY 6.1.3.2 Return Stack Pointer (STKPTR) The STKPTR register (Register 6-1) contains the Stack Pointer value, the STKFUL (Stack Full) status bit and the STKUNF (Stack Underflow) status bits. The value of the Stack Pointer can be 0 through 31. The Stack Pointer increments before values are pushed onto the stack and decrements after values are popped off the stack. On Reset, the Stack Pointer value will be zero. When the stack has been popped enough times to unload the stack, the next pop will return a value of zero to the PC and set the STKUNF bit, while the Stack Pointer remains at zero. The STKUNF bit will remain set until cleared by software or until a POR occurs. Note: The user may read and write the Stack Pointer value. This feature can be used by a Real-Time Operating System (RTOS) for return-stack maintenance. After the PC is pushed onto the stack 31 times (without popping any values off the stack), the STKFUL bit is set. The STKFUL bit is cleared by software or by a POR. What happens when the stack becomes full depends on the state of the STVREN (Stack Overflow Reset Enable) Configuration bit. (For a description of the device Configuration bits, see Section 28.1 “Configuration Bits”.) If STVREN is set (default), the 31st push will push the (PC + 2) value onto the stack, set the STKFUL bit and reset the device. The STKFUL bit will remain set and the Stack Pointer will be set to zero. If STVREN is cleared, the STKFUL bit will be set on the 31st push and the Stack Pointer will increment to 31. Any additional pushes will not overwrite the 31st push and the STKPTR will remain at 31. REGISTER 6-1: 6.1.3.3 Returning a value of zero to the PC on an underflow has the effect of vectoring the program to the Reset vector, where the stack conditions can be verified and appropriate actions can be taken. This is not the same as a Reset, as the contents of the SFRs are not affected. PUSH and POP Instructions Since the Top-of-Stack is readable and writable, the ability to push values onto the stack and pull values off the stack, without disturbing normal program execution, is a desirable feature. The PIC18 instruction set includes two instructions, PUSH and POP, that permit the TOS to be manipulated under software control. TOSU, TOSH and TOSL can be modified to place data or a return address on the stack. The PUSH instruction places the current PC value onto the stack. This increments the Stack Pointer and loads the current PC value onto the stack. The POP instruction discards the current TOS by decrementing the Stack Pointer. The previous value pushed onto the stack then becomes the TOS value. STKPTR: STACK POINTER REGISTER R/C-0 R/C-0 U-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 STKFUL(1) STKUNF(1) — SP4 SP3 SP2 SP1 SP0 bit 7 bit 0 Legend: C = Clearable bit R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7 STKFUL: Stack Full Flag bit(1) 1 = Stack became full or overflowed 0 = Stack has not become full or overflowed bit 6 STKUNF: Stack Underflow Flag bit(1) 1 = Stack underflow occurred 0 = Stack underflow did not occur bit 5 Unimplemented: Read as ‘0’ bit 4-0 SP<4:0>: Stack Pointer Location bits Note 1: x = Bit is unknown Bit 7 and bit 6 are cleared by user software or by a POR. DS39957B-page 86 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 6.1.3.4 Stack Full and Underflow Resets 6.1.5 Device Resets on stack overflow and stack underflow conditions are enabled by setting the STVREN bit (CONFIG4L<0>). When STVREN is set, a full or underflow condition will set the appropriate STKFUL or STKUNF bit and then cause a device Reset. When STVREN is cleared, a full or underflow condition will set the appropriate STKFUL or STKUNF bit, but not cause a device Reset. The STKFUL or STKUNF bits are cleared by the user software or a Power-on Reset. 6.1.4 FAST REGISTER STACK A Fast Register Stack is provided for the STATUS, WREG and BSR registers to provide a “fast return” option for interrupts. This stack is only one level deep and is neither readable nor writable. It is loaded with the current value of the corresponding register when the processor vectors for an interrupt. All interrupt sources will push values into the Stack registers. The values in the registers are then loaded back into the working registers if the RETFIE, FAST instruction is used to return from the interrupt. LOOK-UP TABLES IN PROGRAM MEMORY There may be programming situations that require the creation of data structures, or look-up tables, in program memory. For PIC18 devices, look-up tables can be implemented in two ways: • Computed GOTO • Table Reads 6.1.5.1 Computed GOTO A computed GOTO is accomplished by adding an offset to the program counter. An example is shown in Example 6-2. A look-up table can be formed with an ADDWF PCL instruction and a group of RETLW nn instructions. The W register is loaded with an offset into the table before executing a call to that table. The first instruction of the called routine is the ADDWF PCL instruction. The next instruction executed will be one of the RETLW nn instructions that returns the value ‘nn’ to the calling function. If both low and high-priority interrupts are enabled, the Stack registers cannot be used reliably to return from low-priority interrupts. If a high-priority interrupt occurs while servicing a low-priority interrupt, the Stack register values stored by the low-priority interrupt will be overwritten. In these cases, users must save the key registers in software during a low-priority interrupt. The offset value (in WREG) specifies the number of bytes that the program counter should advance and should be multiples of two (LSb = 0). If interrupt priority is not used, all interrupts may use the Fast Register Stack for returns from interrupt. If no interrupts are used, the Fast Register Stack can be used to restore the STATUS, WREG and BSR registers at the end of a subroutine call. To use the Fast Register Stack for a subroutine call, a CALL label, FAST instruction must be executed to save the STATUS, WREG and BSR registers to the Fast Register Stack. A RETURN, FAST instruction is then executed to restore these registers from the Fast Register Stack. EXAMPLE 6-2: Example 6-1 shows a source code example that uses the Fast Register Stack during a subroutine call and return. EXAMPLE 6-1: CALL SUB1, FAST FAST REGISTER STACK CODE EXAMPLE ;STATUS, WREG, BSR ;SAVED IN FAST REGISTER ;STACK RETURN FAST SUB1 ;RESTORE VALUES SAVED ;IN FAST REGISTER STACK 2010 Microchip Technology Inc. In this method, only one data byte may be stored in each instruction location and room on the return address stack is required. ORG TABLE 6.1.5.2 MOVF CALL nn00h ADDWF RETLW RETLW RETLW . . . COMPUTED GOTO USING AN OFFSET VALUE OFFSET, W TABLE PCL nnh nnh nnh Table Reads A better method of storing data in program memory allows two bytes of data to be stored in each instruction location. Look-up table data may be stored two bytes per program word while programming. The Table Pointer (TBLPTR) specifies the byte address and the Table Latch (TABLAT) contains the data that is read from the program memory. Data is transferred from program memory one byte at a time. The table read operation is discussed further in Section 7.1 “Table Reads and Table Writes”. Preliminary DS39957B-page 87 PIC18F87K90 FAMILY 6.2 PIC18 Instruction Cycle 6.2.1 6.2.2 An “Instruction Cycle” consists of four Q cycles, Q1 through Q4. The instruction fetch and execute are pipelined in such a manner that a fetch takes one instruction cycle, while the decode and execute take another instruction cycle. However, due to the pipelining, each instruction effectively executes in one cycle. If an instruction (such as GOTO) causes the program counter to change, two cycles are required to complete the instruction. (See Example 6-3.) CLOCKING SCHEME The microcontroller clock input, whether from an internal or external source, is internally divided by four to generate four non-overlapping quadrature clocks (Q1, Q2, Q3 and Q4). Internally, the program counter is incremented on every Q1, with the instruction fetched from the program memory and latched into the Instruction Register (IR) during Q4. The instruction is decoded and executed during the following Q1 through Q4. The clocks and instruction execution flow are shown in Figure 6-4. FIGURE 6-4: INSTRUCTION FLOW/PIPELINING A fetch cycle begins with the Program Counter (PC) incrementing in Q1. In the execution cycle, the fetched instruction is latched into the Instruction Register (IR) in cycle Q1. This instruction is then decoded and executed during the Q2, Q3 and Q4 cycles. Data memory is read during Q2 (operand read) and written during Q4 (destination write). CLOCK/INSTRUCTION CYCLE Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 OSC1 Q1 Q2 Internal Phase Clock Q3 Q4 PC PC PC + 2 PC + 4 OSC2/CLKO (RC mode) Execute INST (PC – 2) Fetch INST (PC) EXAMPLE 6-3: 1. MOVLW 55h 4. BSF Execute INST (PC + 2) Fetch INST (PC + 4) INSTRUCTION PIPELINE FLOW TCY0 TCY1 Fetch 1 Execute 1 2. MOVWF PORTB 3. BRA Execute INST (PC) Fetch INST (PC + 2) SUB_1 Fetch 2 TCY2 TCY3 TCY4 TCY5 Execute 2 Fetch 3 Execute 3 Fetch 4 PORTA, BIT3 (Forced NOP) Flush (NOP) Fetch SUB_1 Execute SUB_1 5. Instruction @ address SUB_1 All instructions are single cycle, except for any program branches. These take two cycles since the fetch instruction is “flushed” from the pipeline while the new instruction is being fetched and then executed. DS39957B-page 88 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 6.2.3 INSTRUCTIONS IN PROGRAM MEMORY The program memory is addressed in bytes. Instructions are stored as two or four bytes in program memory. The Least Significant Byte of an instruction word is always stored in a program memory location with an even address (LSB = 0). To maintain alignment with instruction boundaries, the PC increments in steps of two and the LSB will always read ‘0’ (see Section 6.1.2 “Program Counter”). Figure 6-5 shows an example of how instruction words are stored in the program memory. FIGURE 6-5: The CALL and GOTO instructions have the absolute program memory address embedded into the instruction. Since instructions are always stored on word boundaries, the data contained in the instruction is a word address. The word address is written to PC<20:1> which accesses the desired byte address in program memory. Instruction #2 in Figure 6-5 shows how the instruction, GOTO 0006h, is encoded in the program memory. Program branch instructions, which encode a relative address offset, operate in the same manner. The offset value stored in a branch instruction represents the number of single-word instructions that the PC will be offset by. For more details on the instruction set, see Section 29.0 “Instruction Set Summary”. INSTRUCTIONS IN PROGRAM MEMORY LSB = 1 LSB = 0 0Fh EFh F0h C1h F4h 55h 03h 00h 23h 56h Program Memory Byte Locations 6.2.4 Instruction 1: Instruction 2: MOVLW GOTO 055h 0006h Instruction 3: MOVFF 123h, 456h TWO-WORD INSTRUCTIONS The standard PIC18 instruction set has four two-word instructions: CALL, MOVFF, GOTO and LSFR. In all cases, the second word of the instructions always has ‘1111’ as its four Most Significant bits. The other 12 bits are literal data, usually a data memory address. The use of ‘1111’ in the 4 MSbs of an instruction specifies a special form of NOP. If the instruction is executed in proper sequence, immediately after the first word, the data in the second word is accessed and EXAMPLE 6-4: Word Address 000000h 000002h 000004h 000006h 000008h 00000Ah 00000Ch 00000Eh 000010h 000012h 000014h used by the instruction sequence. If the first word is skipped for some reason, and the second word is executed by itself, a NOP is executed instead. This is necessary for cases when the two-word instruction is preceded by a conditional instruction that changes the PC. Example 6-4 shows how this works. Note: For information on two-word instructions in the extended instruction set, see Section 6.5 “Program Memory and the Extended Instruction Set”. TWO-WORD INSTRUCTIONS CASE 1: Object Code Source Code 0110 0110 0000 0000 TSTFSZ REG1 1100 0001 0010 0011 MOVFF REG1, REG2 ; No, skip this word ADDWF REG3 ; continue code ; is RAM location 0? 1111 0100 0101 0110 0010 0100 0000 0000 ; is RAM location 0? ; Execute this word as a NOP CASE 2: Object Code Source Code 0110 0110 0000 0000 TSTFSZ REG1 1100 0001 0010 0011 MOVFF REG1, REG2 ; Yes, execute this word 1111 0100 0101 0110 0010 0100 0000 0000 2010 Microchip Technology Inc. ; 2nd word of instruction ADDWF REG3 ; continue code Preliminary DS39957B-page 89 PIC18F87K90 FAMILY 6.3 Note: Data Memory Organization 6.3.1 The operation of some aspects of data memory are changed when the PIC18 extended instruction set is enabled. See Section 6.6 “Data Memory and the Extended Instruction Set” for more information. The data memory in PIC18 devices is implemented as static RAM. Each register in the data memory has a 12-bit address, allowing up to 4,096 bytes of data memory. The memory space is divided into as many as 16 banks that contain 256 bytes each. PIC18FX6K90 and PIC18FX7K90 devices implement all 16 complete banks, for a total of 4 Kbytes. PIC18FX5K90 devices implement only the first eight complete banks, for a total of 2 Kbytes. Figure 6-6 and Figure 6-7 show the data memory organization for the devices. The data memory contains Special Function Registers (SFRs) and General Purpose Registers (GPRs). The SFRs are used for control and status of the controller and peripheral functions, while GPRs are used for data storage and scratchpad operations in the user’s application. Any read of an unimplemented location will read as ‘0’s. The instruction set and architecture allow operations across all banks. The entire data memory may be accessed by Direct, Indirect or Indexed Addressing modes. Addressing modes are discussed later in this section. To ensure that commonly used registers (select SFRs and select GPRs) can be accessed in a single cycle, PIC18 devices implement an Access Bank. This is a 256-byte memory space that provides fast access to select SFRs and the lower portion of GPR Bank 0 without using the Bank Select Register. For details on the Access RAM, see Section 6.3.2 “Access Bank”. BANK SELECT REGISTER Large areas of data memory require an efficient addressing scheme to make possible rapid access to any address. Ideally, this means that an entire address does not need to be provided for each read or write operation. For PIC18 devices, this is accomplished with a RAM banking scheme. This divides the memory space into 16 contiguous banks of 256 bytes. Depending on the instruction, each location can be addressed directly by its full 12-bit address, or an 8-bit, low-order address and a four-bit Bank Pointer. Most instructions in the PIC18 instruction set make use of the Bank Pointer, known as the Bank Select Register (BSR). This SFR holds the four Most Significant bits of a location’s address. The instruction itself includes the eight Least Significant bits. Only the four lower bits of the BSR are implemented (BSR<3:0>). The upper four bits are unused, always read as ‘0’ and cannot be written to. The BSR can be loaded directly by using the MOVLB instruction. The value of the BSR indicates the bank in data memory. The eight bits in the instruction show the location in the bank and can be thought of as an offset from the bank’s lower boundary. The relationship between the BSR’s value and the bank division in data memory is shown in Figure 6-7. Since up to 16 registers may share the same low-order address, the user must always be careful to ensure that the proper bank is selected before performing a data read or write. For example, writing what should be program data to an 8-bit address of F9h while the BSR is 0Fh, will end up resetting the program counter. While any bank can be selected, only those banks that are actually implemented can be read or written to. Writes to unimplemented banks are ignored, while reads from unimplemented banks will return ‘0’s. Even so, the STATUS register will still be affected as if the operation was successful. The data memory map in Figure 6-6 indicates which banks are implemented. In the core PIC18 instruction set, only the MOVFF instruction fully specifies the 12-bit address of the source and target registers. When this instruction executes, it ignores the BSR completely. All other instructions include only the low-order address as an operand and must use either the BSR or the Access Bank to locate their target registers. DS39957B-page 90 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY FIGURE 6-6: DATA MEMORY MAP FOR PIC18FX5K90 AND PIC18FX7K90 DEVICES BSR<3:0> Data Memory Map 00h = 0000 = 0001 = 0010 = 0011 = 0100 = 0101 = 0110 = 0111 = 1000 = 1001 = 1010 = 1011 = 1100 = 1101 = 1110 = 1111 Bank 0 FFh 00h Bank 1 Access RAM GPR GPR 1FFh 200h FFh 00h Bank 2 GPR FFh 00h Bank 3 2FFh 300h GPR FFh 00h Bank 4 The second 160 bytes are Special Function Registers (from Bank 15). When a = 1: 3FFh 400h The BSR specifies the bank used by the instruction. 5FFh 600h GPR Bank 6 FFh 00h 6FFh 700h GPR Bank 7 FFh 00h 7FFh 800h GPR(2) Bank 8 FFh 00h 8FFh 900h Access Bank Access RAM Low 00h 5Fh Access RAM High 60h (SFRs) FFh GPR(2) Bank 9 FFh 00h Bank 13 The first 96 bytes are general purpose RAM (from Bank 0). 4FFh 500h FFh 00h Bank 12 The BSR is ignored and the Access Bank is used. GPR Bank 5 Bank 11 When a = 0: GPR FFh 00h Bank 10 000h 05Fh 060h 0FFh 100h FFh 00h FFh 00h FFh 00h FFh 00h Bank 14 GPR(2) GPR(2) GPR(2) GPR(2) GPR(1,2) FFh 00h GPR(1,2) FFh SFR Bank 15 9FFh A00h AFFh B00h BFFh C00h CFFh D00h DFFh E00h EFFh F00h F5Fh F60h FFFh Note 1: Addresses, EF4h through F5Fh, are also used by SFRs, but are not part of the Access RAM. Users must always use the complete address, or load the proper BSR value, to access these registers. 2: These addresses are unused for devices with 32 Kbytes of program memory (PIC18FX5K90). For those devices, read these addresses at 00h. 2010 Microchip Technology Inc. Preliminary DS39957B-page 91 PIC18F87K90 FAMILY FIGURE 6-7: USE OF THE BANK SELECT REGISTER (DIRECT ADDRESSING) BSR(1) 7 0 0 0 0 0 0 0 Bank Select(2) 1 0 000h Data Memory Bank 0 100h Bank 1 7 FFh 00h 1 From Opcode(2) 1 11 1 11 1 0 11 11 FFh 00h 200h 300h 00h Bank 2 FFh 00h Bank 3 through Bank 13 FFh 00h E00h Bank 14 FFh 00h F00h FFFh Note 1: 2: 6.3.2 Bank 15 The Access RAM bit of the instruction can be used to force an override of the selected bank (BSR<3:0>) to the registers of the Access Bank. The MOVFF instruction embeds the entire 12-bit address in the instruction. ACCESS BANK While the use of the BSR, with an embedded 8-bit address, allows users to address the entire range of data memory, it also means that the user must ensure that the correct bank is selected. If not, data may be read from, or written to, the wrong location. This can be disastrous if a GPR is the intended target of an operation, but an SFR is written to instead. But verifying and/or changing the BSR for each read or write to data memory can become very inefficient. To streamline access for the most commonly used data memory locations, the data memory is configured with an Access Bank, which allows users to access a mapped block of memory without specifying a BSR. The Access Bank consists of the first 96 bytes of memory (00h-5Fh) in Bank 0 and the last 160 bytes of memory (60h-FFh) in Bank 15. The lower half is known as the “Access RAM” and is composed of GPRs. The upper half is where the device’s SFRs are mapped. These two areas are mapped contiguously in the Access Bank and can be addressed in a linear fashion by an 8-bit address (Figure 6-6). The Access Bank is used by core PIC18 instructions that include the Access RAM bit (the ‘a’ parameter in the instruction). When ‘a’ is equal to ‘1’, the instruction uses the BSR and the 8-bit address included in the opcode for the data memory address. When ‘a’ is ‘0’, however, the instruction is forced to use the Access Bank address map. In that case, the current value of the BSR is ignored entirely. DS39957B-page 92 FFh Using this “forced” addressing allows the instruction to operate on a data address in a single cycle without updating the BSR first. For 8-bit addresses of 60h and above, this means that users can evaluate and operate on SFRs more efficiently. The Access RAM below 60h is a good place for data values that the user might need to access rapidly, such as immediate computational results or common program variables. Access RAM also allows for faster and more code efficient context saving and switching of variables. The mapping of the Access Bank is slightly different when the extended instruction set is enabled (XINST Configuration bit = 1). This is discussed in more detail in Section 6.6.3 “Mapping the Access Bank in Indexed Literal Offset Mode”. 6.3.3 GENERAL PURPOSE REGISTER FILE PIC18 devices may have banked memory in the GPR area. This is data RAM which is available for use by all instructions. GPRs start at the bottom of Bank 0 (address 000h) and grow upwards towards the bottom of the SFR area. GPRs are not initialized by a Power-on Reset and are unchanged on all other Resets. Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 6.3.4 SPECIAL FUNCTION REGISTERS The Special Function Registers (SFRs) are registers used by the CPU and peripheral modules for controlling the desired operation of the device. These registers are implemented as static RAM. SFRs start at the top of data memory (FFFh) and extend downward to occupy all of Bank 15 (F00h to FFFh) and the top part of Bank 14 (EF4h to EFFh). A list of these registers is given in Table 6-1 and Table 6-2. The SFRs can be classified into two sets: those associated with the “core” device functionality (ALU, Resets and interrupts) and those related to the peripheral functions. The Reset and Interrupt registers are described in their respective chapters, while the ALU’s STATUS register is described later in this section. Registers related to the operation of the peripheral features are described in the chapter for that peripheral. The SFRs are typically distributed among the peripherals whose functions they control. Unused SFR locations are unimplemented and read as ‘0’s. PIC18F87K90 FAMILY SPECIAL FUNCTION REGISTER MAP(5) TABLE 6-1: Addr. Name Addr. Name Addr. Name Addr. Name Addr. Name Addr. Name FFFh TOSU FDFh INDF2(1) FBFh ECCP1AS F9Fh IPR1 F7Fh EECON1 F5Fh RTCCFG FFEh TOSH FDEh POSTINC2(1) FBEh ECCP1DEL F9Eh PIR1 F7Eh EECON2 F5Eh RTCCAL FFDh TOSL FDDh POSTDEC2(1) FBDh CCPR1H F9Dh PIE1 F7Dh LCDDATA23(3) F5Dh RTCVALH FFCh STKPTR FDCh PREINC2(1) CCPR1L F9Ch PSTR1CON F7Ch LCDDATA22(3) F5Ch RTCVALL FFBh PCLATU FDBh PLUSW2 (1) FBBh CCP1CON F9Bh OSCTUNE F7Bh LCDDATA21 F5Bh ALRMCFG FFAh PCLATH FDAh FBAh F9Ah TRISJ(3) F7Ah LCDDATA20 F5Ah ALRMRPT (3) F79h LCDDATA19 F59h ALRMVALH LCDDATA18 F58h ALRMVALL FSR2H FBCh PIR5 FF9h PCL FD9h FSR2L FB9h PIE5 F99h FF8h TBLPTRU FD8h STATUS FB8h IPR4 F98h TRISH TRISG F78h FF7h TBLPTRH FD7h TMR0H FB7h PIR4 F97h TRISF F77h LCDDATA17(3) F57h CTMUCONH FF6h TBLPTRL FD6h TMR0L FB6h PIE4 F96h TRISE F76h LCDDATA16(3) F56h CTMUCONL FF5h TABLAT FD5h T0CON FB5h CVRCON F95h TRISD F75h LCDDATA15 F55h CTMUICON FF4h PRODH FD4h SPBRGH1 FB4h CMSTAT F94h TRISC F74h LCDDATA14 F54h CMCON1 FF3h PRODL FD3h OSCCON FB3h TMR3H F93h TRISB F73h LCDDATA13 F53h PADCFG1 FF2h INTCON FD2h IPR5 FB2h TMR3L F92h TRISA F72h LCDDATA12 F52h ECCP2AS FF1h INTCON2 FD1h WDTCON FB1h T3CON F91h LATJ(3) F71h LCDDATA11(3) F51h ECCP2DEL FF0h INTCON3 FD0h RCON FB0h T3GCON F90h LATH(3) F70h LCDDATA10(3) F50h CCPR2H FEFh INDF0(1) FCFh TMR1H FAFh SPBRG1 F8Fh LATG F6Fh F4Fh CCPR2L (1) FEEh POSTINC0 LCDDATA9 FCEh TMR1L FAEh RCREG1 F8Eh LATF F6Eh LCDDATA8 F4Eh CCP2CON FEDh POSTDEC0(1) FCDh T1CON FADh TXREG1 F8Dh LATE F6Dh LCDDATA7 F4Dh ECCP3AS LCDDATA6 (1) FCCh TMR2 FACh TXSTA1 F8Ch LATD F6Ch F4Ch ECCP3DEL FEBh PLUSW0(1) FCBh PR2 FABh RCSTA1 F8Bh LATC F6Bh LCDDATA5(3) F4Bh CCPR3H FEAh FSR0H FCAh T2CON FAAh T1GCON F8Ah LATB F6Ah LCDDATA4(3) F4Ah CCPR3L FE9h FSR0L FC9h SSP1BUF FA9h IPR6 F89h LATA FE8h WREG FC8h SSP1ADD FA8h HLVDCON FE7h INDF1(1) FECh PREINC0 F69h LCDDATA3 F49h CCP3CON F88h PORTJ(3) F68h LCDDATA2 F48h CCPR8H FC7h SSP1STAT FA7h —(2) F87h PORTH(3) F67h LCDDATA1 F47h CCPR8L FE6h POSTINC1(1) FC6h SSP1CON1 FA6h PIR6 F86h PORTG F66h LCDDATA0 F46h CCP8CON FE5h POSTDEC1(1) FC5h SSP1CON2 FA5h IPR3 F85h PORTF F65h BAUDCON1 F45h CCPR9H(4) FE4h PREINC1(1) FC4h ADRESH FA4h PIR3 F84h PORTE F64h OSCCON2 F44h CCPR9L(4) (1) FC3h ADRESL FA3h PIE3 F83h PORTD F63h EEADRH F43h CCP9CON(4) FE3h PLUSW1 FE2h FSR1H FC2h ADCON0 FA2h IPR2 F82h PORTC F62h EEADR F42h CCPR10H(4) FE1h FSR1L FC1h ADCON1 FA1h PIR2 F81h PORTB F61h EEDATA F41h FE0h BSR FC0h ADCON2 FA0h PIE2 F80h PORTA F60h PIE6 Note 1: 2: 3: 4: 5: CCPR10L(4) F40h CCP10CON(4) This is not a physical register. Unimplemented registers are read as ‘0’. This register is not available on 64-pin devices (PIC18F6XK90). This register is not available on devices with a program memory of 32 Kbytes (PIC18FX5K90). Addresses, EF4h through F5Fh, are also used by SFRs, but are not part of the Access RAM. Users must always load the proper BSR value to access these registers. 2010 Microchip Technology Inc. Preliminary DS39957B-page 93 PIC18F87K90 FAMILY PIC18F87K90 FAMILY SPECIAL FUNCTION REGISTER MAP(5) (CONTINUED) TABLE 6-1: Name Addr. Addr. Name Name Name Addr. F3Fh TMR7H F32h F3Eh TMR7L(4) F31h F3Dh T7CON(4) F30h T12CON(4) F3Ch T7GCON(4) F2Fh F3Bh TMR6 F2Eh F3Ah PR6 F2Dh CCPTMRS0 F39H T6CON F2Ch CCPTMRS1 F38h TMR8 F2Bh CCPTMRS2 F1Eh F37h PR8 F2Ah REFOCON F1Dh TXREG2 F0Fh CCP4CON TMR12 (4) Addr. (4) Addr. Name Addr. Name F25h ANCON0 F18h PMD1 F0Bh CCPR6H EFEh SSP2CON2 F24h ANCON1 F17h PMD2 F0Ah CCPR6L EFDh LCDREF F23h ANCON2 F16h PMD3 F09h CCP6CON EFCh LCDRL CM2CON F22h RCSTA2 F15h TMR5H F08h CCPR7H EFBh LCDSE5(3) CM3CON F21h TXSTA2 F14h TMR5L F07h CCPR7L EFAh LCDSE4 F20h BAUDCON2 F13h T5CON F06h CCP7CON EF9h LCDSE3 F1Fh SPBRGH2 F12h T5GCON F05h TMR4 EF8h LCDSE2 SPBRG2 F11h CCPR4H F04h PR4 EF7h LCDSE1 RCREG2 F10h F03h T4CON EF6h LCDSE0 F02h LCDPS LCDCON PR12(4) CCPR4L F36h T8CON F29H ODCON1 F1Ch SSP2BUF EF5h F35h TMR10(4) F28h ODCON2 F1Bh PSTR2CON F0Eh CCPR5H F01h SSP2ADD EF4h F34h PR10(4) F27h ODCON3 F1Ah PSTR3CON F0Dh F00h SSP2STAT F26h — F19h F0Ch CCP5CON EFFh SSP2CON1 F33h T10CON Note 1: 2: 3: 4: 5: (4) PMD0 CCPR5L This is not a physical register. Unimplemented registers are read as ‘0’. This register is not available on 64-pin devices (PIC18F6XK90). This register is not available on devices with a program memory of 32 Kbytes (PIC18FX5K90). Addresses, EF4h through F5Fh, are also used by SFRs, but are not part of the Access RAM. Users must always load the proper BSR value to access these registers. DS39957B-page 94 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY TABLE 6-2: Address PIC18F87K90 FAMILY REGISTER FILE SUMMARY File Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Value on POR, BOR EF4h LCDCON LCDEN SLPEN WERR — CS1 CS0 LMUX1 LMUX0 000- 0000 EF5h LCDPS WFT BIASMD LCDA WA LP3 LP2 LP1 LP0 0000 0000 EF6h LCDSE0 SE07 SE06 SE05 SE04 SE03 SE02 SE01 SE00 0000 0000 EF7h LCDSE1 SE15 SE14 SE13 SE12 SE11 SE10 SE09 SE08 0000 0000 EF8h LCDSE2 SE23 SE22 SE21 SE20 SE19 SE18 SE17 SE16 0000 0000 EF9h LCDSE3 SE31 SE30 SE29 SE28 SE27 SE26 SE25 SE24 0000 0000 EFAh LCDSE4 SE39 SE38 S37 SE36 SE35 SE34 SE33 SE32 0000 0000 EFBh LCDSE5(2) SE47 SE46 SE45 SE44 SE43 SE42 SE41 SE40 0000 0000 EFCh LCDRL LRLAP1 LRLAP0 LRLBP1 LRLBP0 — LRLAT2 LRLAT1 LRLAT0 0000 -000 EFDh LCDREF LCDIRE LCDIRS LCDCST2 LCDCST1 LCDCST0 VLCD3PE VLCD2PE VLCD1PE 0000 0000 EFEh SSP2CON2 GCEN ACKSTAT ACKDT ACKEN RCEN PEN RSEN SEN 0000 0000 EFFh SSP2CON1 WCOL SSPOV SSPEN CKP SSPM3 SSPM2 SSPM1 SSPM0 0000 0000 F00h SSP2STAT SMP CKE D/A P S R/W UA BF 0000 0000 F01h SSP2ADD MSSP Address Register in I2C™ Slave Mode. SSP1 Baud Rate Reload Register in I2C Master Mode F02h SSP2BUF MSSP Receive Buffer/Transmit Register F03h T4CON — xxxx xxxx T4OUTPS3 T4OUTPS2 T4OUTPS1 T4OUTPS0 F04h PR4 Timer4 Period Register F05h TMR4 Timer4 Register F06h CCP7CON F07h CCPR7L Capture/Compare/PWM Register 7 Low Byte F08h CCPR7H Capture/Compare/PWM Register7 High Byte F09h CCP6CON F0Ah CCPR6L Capture/Compare/PWM Register 6 Low Byte F0Bh CCPR6H Capture/Compare/PWM Register6 High Byte F0Ch CCP5CON F0Dh CCPR5L Capture/Compare/PWM Register 5 Low Byte F0Eh CCPR5H Capture/Compare/PWM Register 5 High Byte F0Fh CCP4CON F10h CCPR4L Capture/Compare/PWM Register 4 Low Byte F11h CCPR4H Capture/Compare/PWM Register 4 High Byte F12h T5GCON F13h T5CON F14h TMR5L Timer5 Register Low Byte F15h TMR5H Timer5 Register High Byte F16h PMD3 CCP10MD(3) CCP9MD(3) — — — — 0000 0000 TMR4ON T4CKPS1 T4CKPS0 -000 0000 0000 0000 1111 1111 — — — — DC7B1 DC7B0 DC6B1 DC6B0 DC5B1 DC5B0 DC4B1 DC4B0 CCP7M3 CCP7M2 CCP7M1 CCP7M0 --00 0000 xxxx xxxx xxxx xxxx CCP6M3 CCP6M2 CCP6M1 CCP6M0 --00 0000 xxxx xxxx xxxx xxxx CCP5M3 CCP5M2 CCP5M1 CCP5M0 --00 0000 xxxx xxxx xxxx xxxx CCP4M3 CCP4M2 CCP4M1 CCP4M0 --00 0000 xxxx xxxx xxxx xxxx TMR5GE T5GPOL T5GTM T5GSPM T5GGO/ T5DONE T5GVAL T5GSS1 T5GSS0 0000 0000 TMR5CS1 TMR5CS0 T5CKPS1 T5CKPS0 SOSCEN T5SYNC RD16 TMR5ON 0000 0000 0000 0000 xxxx xxxx CCP8MD CCP7MD CCP6MD CCP5MD CCP4MD TMR12MD(3) 0000 0000 F17h PMD2 TMR10MD(3) TMR8MD TMR7MD(3) TMR6MD TMR5MD CMP3MD CMP2MD CMP1MD 0000 0000 F18h PMD1 — CTMUMD RTCCMD TMR4MD TMR3MD TMR2MD TMR1MD — -000 000- F19h PMD0 CCP3MD CCP2MD CCP1MD UART2MD UART1MD SSP2MD SSP1MD ADCMD 0000 0000 F1Ah PSTR3CON CMPL1 CMPL0 — STRSYNC STRD STRC STRB STRA 00-0 0001 F1Bh PSTR2CON CMPL1 CMPL0 — STRSYNC STRD STRC STRB STRA 00-0 0001 F1Ch TXREG2 Transmit Data FIFO xxxx xxxx F1Dh RCREG2 Receive Data FIFO 0000 0000 F1Eh SPBRG2 USART2 Baud Rate Generator Low Byte 0000 0000 F1Fh SPBRGH2 USART2 Baud Rate Generator High Byte F20h BAUDCON2 ABDOVF RCIDL RXDTP 0000 0000 TXCKP BRG16 — WUE ABDEN 0100 0-00 0000 0010 F21h TXSTA2 CSRC TX9 TXEN SYNC SENDB BRGH TRMT TX9D F22h RCSTA2 SPEN RX9 SREN CREN ADDEN FERR OERR RX9D 0000 000x F23h ANCON2 ANSEL23 ANSEL22 ANSEL21 ANSEL20 ANSEL19 ANSEL18 ANSEL17 ANSEL16 1111 1111 Note 1: 2: 3: Bit is available when Master Clear is disabled (MCLRE = 0). When MCLRE is set, bit is unimplemented. Unimplemented on 64-pin devices (PIC18F6XK90). Unimplemented on devices with a program memory of 32 Kbytes (PIC18FX5K90). 2010 Microchip Technology Inc. Preliminary DS39957B-page 95 PIC18F87K90 FAMILY TABLE 6-2: Address PIC18F87K90 FAMILY REGISTER FILE SUMMARY (CONTINUED) File Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Value on POR, BOR F24h ANCON1 ANSEL15 ANSEL14 ANSEL13 ANSEL12 ANSEL11 ANSEL10 ANSEL9 ANSEL8 1111 1111 F25h ANCON0 ANSEL7 ANSEL6 ANSEL5 ANSEL4 ANSEL3 ANSEL2 ANSEL1 ANSEL0 1111 1111 — — — — — — — — — ODCON3 U2OD U1OD — — — — — CTMUDS 00-- ---0 0000 0000 — F27h F28h ODCON2 CCP10OD CCP9OD CCP8OD CCP7OD CCP6OD CCP5OD CCP4OD CCP3OD F29H ODCON1 SSP1OD CCP2OD CCP1OD — — — — SSP2OD 000- ---0 F2Ah REFOCON ROON — ROSSLP ROSEL RODIV3 RODIV2 RODIV1 RODIV0 0-00 0000 F2Bh CCPTMRS2 — — — C10TSEL0 — C9TSEL0 C8TSEL1 C8TSEL0 ---0 -000 F2Ch CCPTMRS1 C7TSEL1 C7TSEL0 — C6TSEL0 — C5TSEL0 C4TSEL1 C4TSEL0 00-0 -000 F2Dh CCPTMRS0 C3TSEL1 C3TSEL0 C2TSEL2 C2TSEL1 C2TSEL0 C1TSEL2 C1TSEL1 C1TSEL0 0000 0000 F2Eh CM3CON CON COE CPOL EVPOL1 EVPOL0 CREF CCH1 CCH0 0001 1111 F2Fh CM2CON CON COE CPOL EVPOL1 EVPOL0 CREF CCH1 CCH0 0001 1111 F30h T12CON — T12CKPS1 T12CKPS0 -000 0000 F31h PR12 Timer12 Period Register F32h TMR12 TMR12 Register F33h T10CON F34h PR10 Timer10 Period Register F35h TMR10 TMR10 Register F36h T8CON F37h PR8 Timer8 Period Register F38h TMR8 Timer8 Register F39H T6CON F3Ah PR6 Timer6 Period Register F3Bh TMR6 Timer6 Register F3Ch T7GCON(3) F3Dh T7CON(3) F3Eh TMR7L(3) Timer7 Register Low Byte Timer7 Register High Byte — — — T12OUTPS3 T12OUTPS2 T12OUTPS1 T12OUTPS0 TMR12ON 1111 1111 0000 0000 T10OUTPS3 T10OUTPS2 T10OUTPS1 T10OUTPS0 TMR10ON TMR8ON T8CKPS1 T8CKPS0 0000 0000 T6OUTPS3 T6OUTPS2 T6OUTPS1 T6OUTPS0 TMR6ON T6CKPS1 T6CKPS0 0000 0000 T7GTM T7GSPM T7GGO/ T7DONE T7GVAL T7GSS1 T7GSS0 TMR7CS1 TMR7CS0 T7CKPS1 T7CKPS0 — T7SYNC RD16 TMR7ON TMR7H(3) F41h CCPR10L(3) Capture/Compare/PWM Register 10 Low Byte F42h CCPR10H(3) Capture/Compare/PWM Register 10 High Byte F43h CCP9CON(3) F44h CCPR9L(3) Capture/Compare/PWM Register 9 Low Byte F45h CCPR9H(3) Capture/Compare/PWM Register 9 High Byte F46h CCP8CON F47h CCPR8L Capture/Compare/PWM Register 8 Low Byte F48h CCPR8H Capture/Compare/PWM Register 8 High Byte F49h CCP3CON F4Ah CCPR3L Capture/Compare/PWM Register 3 Low Byte F4Bh CCPR3H Capture/Compare/PWM Register 3 High Byte F4Ch ECCP3DEL F4Dh ECCP3AS F4Eh CCP2CON F4Fh CCPR2L P3M1 P3RSEN — — — P3M0 P3DC6 P2M0 0000 0x00 xxxx xxxx DC10B1 DC9B1 DC8B1 DC3B1 P3DC5 DC10B0 DC9B0 DC8B0 DC3B0 P3DC4 ECCP3ASE ECCP3AS2 ECCP3AS1 ECCP3AS0 P2M1 0000 0x00 xxxx xxxx CCP10CON(3) — -000 0000 1111 1111 T7GPOL — -000 0000 1111 1111 TMR7GE — -000 0000 0000 0000 T8OUTPS3 T8OUTPS2 T8OUTPS1 T8OUTPS0 F3Fh 1: 2: 3: T10CKPS0 1111 1111 F40h Note T10CKPS1 DC2B1 DC2B0 CCP10M3 CCP10M2 CCP10M1 CCP10M0 --00 0000 xxxx xxxx xxxx xxxx CCP9M3 CCP9M2 CCP9M1 CCP9M0 --00 0000 xxxx xxxx xxxx xxxx CCP8M3 CCP8M2 CCP8M1 CCP8M0 --00 0000 xxxx xxxx xxxx xxxx CCP3M3 CCP3M2 CCP3M1 CCP3M0 0000 0000 xxxx xxxx xxxx xxxx P3DC3 P3DC2 P3DC1 P3DC0 0000 0000 PSS3AC1 PSS3AC0 PSS3BD1 PSS3BD0 0000 0000 CCP2M3 CCP2M2 CCP2M1 CCP2M0 0000 0000 Capture/Compare/PWM Register 2 Low Byte xxxx xxxx Bit is available when Master Clear is disabled (MCLRE = 0). When MCLRE is set, bit is unimplemented. Unimplemented on 64-pin devices (PIC18F6XK90). Unimplemented on devices with a program memory of 32 Kbytes (PIC18FX5K90). DS39957B-page 96 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY TABLE 6-2: Address PIC18F87K90 FAMILY REGISTER FILE SUMMARY (CONTINUED) File Name F50h CCPR2H F51h ECCP2DEL F52h ECCP2AS F53h PADCFG1 Bit 7 Bit 6 Bit 5 Bit 4 Bit 2 Bit 1 Bit 0 P2DC3 P2DC2 P2DC1 P2DC0 PSS2AC1 PSS2AC0 PSS2BD1 PSS2BD0 0000 0000 — 000- -00- Capture/Compare/PWM Register 2 High Byte P2RSEN P2DC6 P2DC5 xxxx xxxx P2DC4 ECCP2ASE ECCP2AS2 ECCP2AS1 ECCP2AS0 RDPU REPU Value on POR, BOR Bit 3 RJPU(2) — — RTSECSEL1 RTSECSEL0 0000 0000 F54h CM1CON CON COE CPOL EVPOL1 EVPOL0 CREF CCH1 CCH0 0001 1111 F55h CTMUICON ITRIM5 ITRIM4 ITRIM3 ITRIM2 ITRIM1 ITRIM0 IRNG1 IRNG1 0000 0000 F56h CTMUCONL EDG2POL F57h CTMUCONH CTMUEN F58h ALRMVALL Alarm Value High Register Window based on APTR<1:0> F59h ALRMVALH Alarm Value High Register Window based on APTR<1:0> F5Ah ALRMRPT ARPT7 ARPT6 ARPT5 ARPT4 ARPT3 ARPT2 F5Bh ALRMCFG ALRMEN CHIME AMASK3 AMASK2 AMASK1 AMASK0 F5Ch RTCVALL RTCC Value Low Register Window based on RTCPTR<1:0> F5Dh RTCVALH RTCC Value High Register Window based on RTCPTR<1:0> F5Eh RTCCAL CAL7 CAL6 CAL5 CAL4 CAL3 CAL2 CAL1 CAL0 xxxx xxxx F5Fh RTCCFG RTCEN — RTCWREN RTCSYNC HALFSEC RTCOE RTCPTR1 RTCPTR0 0-00 0000 F60h PIE6 — — — EEIE — CMP3IE CMP2IE CMP1IE F61h EEDATA EDG2SEL1 EDG2SEL0 — CTMUSIDL EDG1POL TGEN EDG1SEL1 EDG1SEL0 EDG2STAT EDG1STAT EDGEN EDGSEQEN IDISSEN CTTRIG 0000 0000 0-00 0000 0000 0000 xxxx xxxx ARPT1 ARPT0 0000 0000 ALRMPTR1 ALRMPTR0 0000 0000 0000 0000 xxxx xxxx EEPROM Data Register ---0 -000 0000 0000 F62h EEADR EEPROM Address Register Low Byte 0000 0000 F63h EEADRH EEPROM Address Register High Byte ---- --00 F64h OSCCON2 — SOSCRUN — — SOSCGO — MFIOFS MFIOSEL -0-- 0-x0 F65h BAUDCON1 ABDOVF RCIDL RXDTP TXCKP BRG16 — WUE ABDEN 0000 0-x0 F66h LCDDATA0 S07C0 S06C0 S05C0 S04C0 S03C0 S02C0 S01C0 S00C0 xxxx xxxx F67h LCDDATA1 S15C0 S14C0 S13C0 S12C0 S11C0 S10C0 S09C0 S08C0 xxxx xxxx F68h LCDDATA2 S23C0 S22C0 S21C0 S20C0 S19C0 S18C0 S17C0 S16C0 xxxx xxxx F69h LCDDATA3 S31C0 S30C0 S29C0 S28C0 S27C0 S26C0 S25C0 S24C0 xxxx xxxx F6Ah LCDDATA4 S39C0 S38C0 S37C0 S36C0 S35C0 S34C0 S33C0 S32C0 xxxx xxxx F6Bh LCDDATA5 S47C0 S46C0 S45C0 S44C0 S43C0 S42C0 S41C0 S40C0 xxxx xxxx F6Ch LCDDATA6 S07C1 S06C1 S05C1 S04C1 S03C1 S02C1 S01C1 S00C1 xxxx xxxx F6Dh LCDDATA7 S15C1 S14C1 S13C1 S12C1 S11C1 S10C1 S09C1 S08C1 xxxx xxxx F6Eh LCDDATA8 S23C1 S22C1 S21C1 S20C1 S19C1 S18C1 S17C1 S16C1 xxxxxxxx F6Fh LCDDATA9 S31C1 S30C1 S29C1 S28C1 S27C1 S26C1 S25C1 S24C1 xxxx xxxx F70h LCDDATA10(2) S39C1(2) S38C1(2) S37C1(2) S36C1(2) S35C1(2) S34C1(2) S33C1(2) S32C1 xxxx xxxx F71h LCDDATA11(2) S47C1 S46C1 S45C1 S44C1 S43C1 S42C1 S41C1 S40C1 xxxx xxxx F72h LCDDATA12 S07C2 S06C2 S05C2 S04C2 S03C2 S02C2 S01C2 S00C2 xxxx xxxx F73h LCDDATA13 S15C2 S14C2 S13C2 S12C2 S11C2 S10C2 S09C2 S08C2 xxxx xxxx F74h LCDDATA14 S23C2 S22C2 S21C2 S20C2 S19C2 S18C2 S17C2 S16C2 xxxx xxxx F75h LCDDATA15 S31C2 S30C2 S29C2 S28C2 S27C2 S26C2 S25C2 S24C2 xxxx xxxx F76h LCDDATA16(2) S39C2(2) S38C2(2) S37C2(2) S36C2(2) S35C2(2) S34C2(2) S33C2(2) S32C2 xxxx xxxx F77h LCDDATA17(2) S47C2 S46C2 S45C2 S44C2 S43C2 S42C2 S41C2 S40C2 xxxx xxxx F78h LCDDATA18 S07C3 S06C3 S05C3 S04C3 S03C3 S02C3 S01C3 S00C3 xxxx xxxx F79h LCDDATA19 S15C3 S14C3 S13C3 S12C3 S11C3 S10C3 S09C3 S08C3 xxxx xxxx F7Ah LCDDATA20 S23C3 S22C3 S21C3 S20C3 S19C3 S18C3 S17C3 S16C3 xxxx xxxx F7Bh LCDDATA21 S31C3 S30C3 S29C3 S28C3 S27C3 S26C3 S25C3 S24C3 xxxx xxxx F7Ch LCDDATA22 S39C3(2) S38C3(2) S37C3(2) S36C3(2) S35C3(2) S34C3(2) S33C3(2) S32C3 xxxx xxxx F7Dh LCDDATA23(2) S47C3 S46C3 S45C3 S44C3 S43C3 S42C3 S41C3 S40C3 xxxx xxxx F7Eh EECON2 F7Fh EECON1 F80h PORTA Note 1: 2: 3: EEPROM Control Register 2 (not a physical register) ---- ---- EEPGD CFGS — FREE WRERR WREN WR RD xx-0 x000 RA7 RA6 RA5 RA4 RA3 RA2 RA1 RA0 xxxx xxxx Bit is available when Master Clear is disabled (MCLRE = 0). When MCLRE is set, bit is unimplemented. Unimplemented on 64-pin devices (PIC18F6XK90). Unimplemented on devices with a program memory of 32 Kbytes (PIC18FX5K90). 2010 Microchip Technology Inc. Preliminary DS39957B-page 97 PIC18F87K90 FAMILY TABLE 6-2: Address PIC18F87K90 FAMILY REGISTER FILE SUMMARY (CONTINUED) File Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Value on POR, BOR F81h PORTB RB7 RB6 RB5 RB4 RB3 RB2 RB1 RB0 xxxx xxxx F82h PORTC RC7 RC6 RC5 RC4 RC3 RC2 RC1 RC0 xxxx xxxx F83h PORTD RD7 RD6 RD5 RD4 RD3 RD2 RD1 RD0 xxxx xxxx F84h PORTE RE7 RE6 RE5 RE4 RE3 RE2 RE1 RE0 xxxx xxxx F85h PORTF RF7 RF6 RF5 RF4 RF3 RF2 RF1 — xxxx xxx- F86h PORTG — — RG5(1) RG4 RG3 RG2 RG1 RG0 --xx xxxx F87h PORTH(2) RH7 RH6 RH5 RH4 RH3 RH2 RH1 RH0 xxxx xxxx F88h PORTJ(2) RJ7 RJ6 RJ5 RJ4 RJ3 RJ2 RJ1 RJ0 xxxx xxxx F89h LATA LATA7 LATA6 LATA5 LATA4 LATA3 LATA2 LATA1 LATA0 xxxx xxxx F8Ah LATB LATB7 LATB6 LATB5 LATB4 LATB3 LATB2 LATB1 LATB0 xxxx xxxx F8Bh LATC LATC7 LATC6 LATC5 LATC4 LATC3 LATC2 LATC1 LATC0 xxxx xxxx F8Ch LATD LATD7 LATD6 LATD5 LATD4 LATD3 LATD2 LATD1 LATD0 xxxx xxxx F8Dh LATE LATE7 LATE6 LATE5 LATE4 LATE3 LATE2 LATE1 LATE0 xxxx xxxx F8Eh LATF LATF7 LATF6 LATF5 LATF4 LATF3 LATF2 LATF1 — xxxx xxx- F8Fh LATG — — — LATG4 LATG3 LATG2 LATG1 LATG0 ---x xxxx F90h LATH(2) LATH7 LATH6 LATH5 LATH4 LATH3 LATH2 LATH1 LATH0 xxxx xxxx F91h LATJ(2) LATJ7 LATJ6 LATJ5 LATJ4 LATJ3 LATJ2 LATJ1 LATJ0 xxxx xxxx F92h TRISA TRISA7 TRISA6 TRISA5 TRISA4 TRISA3 TRISA2 TRISA1 TRISA0 1111 1111 F93h TRISB TRISB7 TRISB6 TRISB5 TRISB4 TRISB3 TRISB2 TRISB1 TRISB0 1111 1111 F94h TRISC TRISC7 TRISC6 TRISC5 TRISC4 TRISC3 TRISC2 TRISC1 TRISC0 1111 1111 F95h TRISD TRISD7 TRISD6 TRISD5 TRISD4 TRISD3 TRISD2 TRISD1 TRISD0 1111 1111 F96h TRISE TRISE7 TRISE6 TRISE5 TRISE4 TRISE3 TRISE2 TRISE1 TRISE0 1111 1111 F97h TRISF TRISF7 TRISF6 TRISF5 TRISF4 TRISF3 TRISF2 TRISF1 — 1111 111- F98h TRISG — — — TRISG4 TRISG3 TRISG2 TRISG1 TRISG0 ---1 1111 F99h TRISH(2) TRISH7 TRISH6 TRISH5 TRISH4 TRISH3 TRISH2 TRISH1 TRISH0 1111 1111 F9Ah TRISJ(2) TRISJ7 TRISJ6 TRISJ5 TRISJ4 TRISJ3 TRISJ2 TRISJ1 TRISJ0 1111 1111 F9Bh OSCTUNE INTSRC PLLEN TUN5 TUN4 TUN3 TUN2 TUN1 TUN0 0000 0000 F9Ch PSTR1CON CMPL1 CMPL0 — STRSYNC STRD STRC STRB STRA 00-0 0001 F9Dh PIE1 — ADIE RC1IE TX1IE SSP1IE TMR1GIE TMR2IE TMR1IE -000 0000 F9Eh PIR1 — ADIF RC1IF TX1IF SSP1IF TMR1GIF TMR2IF TMR1IF -000 0000 F9Fh IPR1 — ADIP RC1IP TX1IP SSP1IP TMR1GIP TMR2IP TMR1IP -111 1111 FA0h PIE2 OSCFIE — SSP2IE BCL2IE BCL1IE HLVDIE TMR3IE TMR3GIE 0-10 0000 FA1h PIR2 OSCFIF — SSP2IF BCL2IF BCL1IF HLVDIF TMR3IF TMR3GIF 0-10 0000 FA2h IPR2 OSCFIP — SSP2IP BCL2IP BCL1IP HLVDIP TMR3IP TMR3GIP 1-00 1110 FA3h PIE3 TMR5GIE LCDIE RC2IE TX2IE CTMUIE CCP2IE CCP1IE RTCCIE 0000 0000 FA4h PIR3 TMR5GIF LCDIF RC2IF TX2IF CTMUIF CCP2IF CCP1IF RTCCIF 0000 0000 FA5h IPR3 TMR5GIP LCDIP RC2IP TX2IP CTMUIP CCP2IP CCP1IP RTCCIP 1111 1111 FA6h PIR6 — — — EEIF — CMP3IF CMP2IF CMP1IF ---0 -000 FA7h — — — — — — — — — ---- ---- FA8h HLVDCON VDIRMAG BGVST IRVST HLVDEN HLVDL3 HLVDL2 HLVDL1 HLVDL0 0000 0000 FA9h IPR6 — — — EEIP — CMP3IP CMP2IP CMP1IP ---1 -111 FAAh T1GCON TMR1GE T1GPOL T1GTM T1GSPM T1GGO/ T1DONE T1GVAL T1GSS1 T1GSS0 0000 0x00 FABh RCSTA1 SPEN RX9 SREN CREN ADDEN FERR OERR RX9D 0000 000x FACh TXSTA1 CSRC TX9 TXEN SYNC SENDB BRGH TRMT TX9D 0000 0010 FADh TXREG1 USART1 Transmit Register xxxx xxxx FAEh RCREG1 USART1 Receive Register 0000 0000 FAFh SPBRG1 USART1 Baud Rate Generator 0000 0000 Note 1: 2: 3: Bit is available when Master Clear is disabled (MCLRE = 0). When MCLRE is set, bit is unimplemented. Unimplemented on 64-pin devices (PIC18F6XK90). Unimplemented on devices with a program memory of 32 Kbytes (PIC18FX5K90). DS39957B-page 98 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY TABLE 6-2: Address PIC18F87K90 FAMILY REGISTER FILE SUMMARY (CONTINUED) File Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Value on POR, BOR TMR3GE T3GPOL T3GTM T3GSPM T3GGO/ T3DONE T3GVAL T3GSS1 T3GSS0 0000 0x00 TMR3CS1 TMR3CS0 T3CKPS1 T3CKPS0 SOSCEN T3SYNC RD16 TMR3ON FB0h T3GCON FB1h T3CON FB2h TMR3L Timer3 Register Low Byte FB3h TMR3H Timer3 Register High Byte FB4h CMSTAT CMP3OUT CMP2OUT 0000 0000 xxxx xxxx xxxx xxxx CMP1OUT — — — — — 111- ---- FB5h CVRCON CVREN CVROE CVRSS CVR4 CVR3 CVR2 CVR1 CVR0 0000 0000 FB6h PIE4 CCP10IE(3) CCP9IE(3) CCP8IE CCP7IE(3) CCP6IE CCP5IE CCP4IE CCP3IE 0000 0000 FB7h PIR4 CCP10IF(3) CCP9IF(3) CCP8IF CCP7IF(3) CCP6IF CCP5IF CCP4IF CCP3IF 0000 0000 FB8h IPR4 CCP10IP(3) CCP9IP(3) CCP8IP CCP7IP(3) CCP6IP CCP5IP CCP4IP CCP3IP 1111 1111 FB9h PIE5 TMR7GIE(3) TMR12IE(3) TMR10IE(3) TMR8IE TMR7IE(3) TMR6IE TMR5IE TMR4IE 0000 0000 TMR8IF TMR7IF(3) TMR6IF TMR5IF TMR4IF 0000 0000 DC1B0 CCP1M3 CCP1M2 CCP1M1 CCP1M0 0000 0000 TMR7GIF (3) TMR12IF (3) TMR10IF (3) FBAh PIR5 FBBh CCP1CON FBCh CCPR1L Capture/Compare/PWM Register 1 Low Byte FBDh CCPR1H Capture/Compare/PWM Register 1 High Byte FBEh ECCP1DEL FBFh ECCP1AS FC0h ADCON2 ADFM — ACQT2 FC1h ADCON1 TRIGSEL1 TRIGSEL0 FC2h ADCON0 — CHS4 FC3h ADRESL A/D Result Register Low Byte FC4h ADRESH A/D Result Register High Byte FC5h SSP1CON2 GCEN ACKSTAT ACKDT ACKEN RCEN PEN RSEN SEN 0000 0000 FC6h SSP1CON1 WCOL SSPOV SSPEN CKP SSPM3 SSPM2 SSPM1 SSPM0 0000 0000 SMP CKE D/A P S R/W UA BF 0000 0000 P1M1 P1M0 P1RSEN DC1B1 P1DC6 P1DC5 xxxx xxxx xxxx xxxx P1DC4 P1DC3 P1DC2 P1DC1 P1DC0 PSS1AC1 PSS1AC0 PSS1BD1 PSS1BD0 0000 0000 ACQT1 ACQT0 ADCS2 ADCS1 ADCS0 0—00 0000 VCFG1 VCFG0 VNCFG CHSN2 CHSN1 CHSN0 0000 0000 CHS3 CHS2 CHS1 CHS0 GO/DONE ADON -000 0000 ECCP1ASE ECCP1AS2 ECCP1AS1 ECCP1AS0 xxxx xxxx xxxx xxxx FC7h SSP1STAT FC8h SSP1ADD MSSP Address Register in I2C™ Slave Mode. SSP1 Baud Rate Reload Register in I2C Master Mode FC9h SSP1BUF MSSP Receive Buffer/Transmit Register FCAh T2CON — PR2 Timer2 Period Register FCCh TMR2 Timer2 Register FCDh T1CON FCEh TMR1L Timer1 Register Low Byte FCFh TMR1H Timer1 Register High Byte FD0h RCON FD1h WDTCON FD2h IPR5 TMR1CS1 TMR2ON T2CKPS1 T2CKPS0 0000 0000 TMR1CS0 T1CKPS1 T1CKPS0 RI REGSLP — ULPLVL SRETEN TMR8IP IRCF0 T0SE TMR7GIP(3) TMR12IP(3) TMR10I(3) P OSCCON FD4h SPBRGH1 IRCF2 FD5h T0CON FD6h TMR0L Timer0 Register Low Byte FD7h TMR0H Timer0 Register High Byte FD8h STATUS T1SYNC RD16 TMR1ON IRCF1 TO PD POR BOR — ULPEN ULPSINK SWDTEN 0—x0 —000 TMR7IP(3) TMR6IP TMR5IP TMR4IP 1111 1111 OSTS HFIOFS SCS1 SCS0 0110 q000 PSA TOPS2 TOPS1 TOPS0 USART1 Baud Rate Generator High Byte — T08BIT — 0000 0000 xxxx xxxx CM FD3h SOSCEN xxxx xxxx SBOREN TMR0ON —000 0000 1111 1111 IPEN IDLEN 0000 0000 xxxx xxxx T2OUTPS3 T2OUTPS2 T2OUTPS1 T2OUTPS0 FCBh 0000 0000 T0CS 0111 11qq 0000 0000 1111 1111 xxxx xxxx 0000 0000 — N OV Z DC C FD9h FSR2L FDAh FSR2H FDBh PLUSW2 Uses contents of FSR2 to address data memory – value of FSR2 pre-incremented (not a physical register) – value of FSR2 offset by W ---- ---- FDCh PREINC2 Uses contents of FSR2 to address data memory – value of FSR2 pre--incremented (not a physical register) ---- ---- FDDh POSTDEC2 Uses contents of FSR2 to address data memory – value of FSR2 post-decremented (not a physical register) ---- ---- FDEh POSTINC2 Uses contents of FSR2 to address data memory – value of FSR2 post-incremented (not a physical register) ---- ---- Note 1: 2: 3: Indirect Data Memory Address Pointer 2 Low Byte ----x xxxx — — — — xxxx xxxx Indirect Data Memory Address Pointer 2 High Byte ---- xxxx Bit is available when Master Clear is disabled (MCLRE = 0). When MCLRE is set, bit is unimplemented. Unimplemented on 64-pin devices (PIC18F6XK90). Unimplemented on devices with a program memory of 32 Kbytes (PIC18FX5K90). 2010 Microchip Technology Inc. Preliminary DS39957B-page 99 PIC18F87K90 FAMILY TABLE 6-2: Address PIC18F87K90 FAMILY REGISTER FILE SUMMARY (CONTINUED) File Name FDFh INDF2 FE0h BSR Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Uses contents of FSR2 to address data memory – value of FSR2 not changed (not a physical register) — — — — Bank Select Register Value on POR, BOR ---- ------- 0000 FE1h FSR1L FE2h FSR1H Indirect Data Memory Address Pointer 1 Low Byte FE3h PLUSW1 Uses contents of FSR1 to address data memory – value of FSR1 pre-incremented (not a physical register) – ---- ---value of FSR1 offset by W FE4h PREINC1 Uses contents of FSR1 to address data memory – value of FSR1 pre-incremented (not a physical register) ---- ---- FE5h POSTDEC1 Uses contents of FSR1 to address data memory – value of FSR1 post-decremented (not a physical register) ---- ---- FE6h POSTINC1 Uses contents of FSR1 to address data memory – value of FSR1 post-incremented (not a physical register) ---- ---- FE7h INDF1 Uses contents of FSR1 to address data memory – value of FSR1 not changed (not a physical register) ---- ---- FE8h WREG Working Register xxxx xxxx FE9h FSR0L Indirect Data Memory Address Pointer 0 Low Byte FEAh FSR0H FEBh PLUSW0 Uses contents of FSR0 to address data memory – value of FSR0 pre-incremented (not a physical register) – ---- ---value of FSR0 offset by W FECh PREINC0 Uses contents of FSR0 to address data memory – value of FSR0 pre-incremented (not a physical register) ---- ---- FEDh POSTDEC0 Uses contents of FSR0 to address data memory – value of FSR0 post-decremented (not a physical register) ---- ---- FEEh POSTINC0 Uses contents of FSR0 to address data memory – value of FSR0 post-incremented (not a physical register) ---- ---- FEFh INDF0 Uses contents of FSR0 to address data memory – value of FSR0 not changed (not a physical register) ---- ---- FF0h INTCON3 INT2IP INT1IP INT3IE INT2IE INT1IE INT3IF INT2IF INT1IF 1100 0000 FF1h INTCON2 RBPU INTEDG0 INTEDG1 INTEDG2 INTEDG3 TMR0IP INT3IP RBIP 1111 1111 FF2h INTCON GIE/GIEH PEIE/GIEL TMR0IE INT0IE RBIE TMR0IF INT0IF RBIF 0000 000x FF3h PRODL Product Register Low Byte FF4h PRODH Product Register High Byte xxxxxxxx FF5h TABLAT Program Memory Table Latch 0000 0000 FF6h TBLPTRL Program Memory Table Pointer Low Byte (TBLPTR<7:0>) 0000 0000 FF7h TBLPTRH Program Memory Table Pointer High Byte (TBLPTR<15:8>) FF8h TBLPTRU — — — — — — — — — — xxxx xxxx Indirect Data Memory Address Pointer 1 High Byte ---- xxxx xxxx xxxx Indirect Data Memory Address Pointer 0 High Byte ---- xxxx xxxx xxxx bit 21 0000 0000 Program Memory Table Pointer Upper Byte (TBLPTR<20:16>) --00 0000 FF9h PCL PC Low Byte (PC<7:0>) FFAh PCLATH Holding Register for PC<15:8> FFBh PCLATU — — — Holding Register for PC<20:16> ---0 0000 FFCh STKPTR STKFUL STKUNF — Return Stack Pointer uu-0 0000 FFDh TOSL Top-of-Stack Low Byte (TOS<7:0>) FFEh TOSH Top-of-Stack High Byte (TOS<15:8>) FFFh TOSU Note 1: 2: 3: — — 0000 0000 0000 0000 — 0000 0000 0000 0000 Top-of-Stack Upper Byte (TOS<20:16>) ---0 0000 Bit is available when Master Clear is disabled (MCLRE = 0). When MCLRE is set, bit is unimplemented. Unimplemented on 64-pin devices (PIC18F6XK90). Unimplemented on devices with a program memory of 32 Kbytes (PIC18FX5K90). DS39957B-page 100 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 6.3.5 STATUS REGISTER The STATUS register, shown in Register 6-2, contains the arithmetic status of the ALU. The STATUS register can be the operand for any instruction, as with any other register. If the STATUS register is the destination for an instruction that affects the Z, DC, C, OV or N bits, the write to these five bits is disabled. These bits are set or cleared according to the device logic. Therefore, the result of an instruction with the STATUS register as destination may be different than intended. For example, CLRF STATUS will set the Z bit but leave the other bits unchanged. The STATUS register then reads back as ‘000u u1uu’. REGISTER 6-2: U-0 For other instructions not affecting any Status bits, see the instruction set summaries in Table 29-2 and Table 29-3. Note: The C and DC bits operate, in subtraction, as borrow and digit borrow bits, respectively. STATUS REGISTER U-0 — It is recommended, therefore, that only BCF, BSF, SWAPF, MOVFF and MOVWF instructions be used to alter the STATUS register because these instructions do not affect the Z, C, DC, OV or N bits in the STATUS register. U-0 — — R/W-x N R/W-x R/W-x R/W-x R/W-x Z DC(1) C(2) OV bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7-5 Unimplemented: Read as ‘0’ bit 4 N: Negative bit This bit is used for signed arithmetic (2’s complement). It indicates whether the result was negative (ALU MSB = 1). 1 = Result was negative 0 = Result was positive bit 3 OV: Overflow bit This bit is used for signed arithmetic (2’s complement). It indicates an overflow of the 7-bit magnitude which causes the sign bit (bit 7) to change state. 1 = Overflow occurred for signed arithmetic (in this arithmetic operation) 0 = No overflow occurred bit 2 Z: Zero bit 1 = The result of an arithmetic or logic operation is zero 0 = The result of an arithmetic or logic operation is not zero bit 1 DC: Digit Carry/Borrow bit(1) For ADDWF, ADDLW, SUBLW and SUBWF instructions: 1 = A carry-out from the 4th low-order bit of the result occurred 0 = No carry-out from the 4th low-order bit of the result bit 0 C: Carry/Borrow bit(2) For ADDWF, ADDLW, SUBLW and SUBWF instructions: 1 = A carry-out from the Most Significant bit of the result occurred 0 = No carry-out from the Most Significant bit of the result occurred Note 1: 2: For borrow, the polarity is reversed. A subtraction is executed by adding the 2’s complement of the second operand. For rotate (RRF, RLF) instructions, this bit is loaded with either bit 4 or bit 3 of the source register. For borrow, the polarity is reversed. A subtraction is executed by adding the 2’s complement of the second operand. For rotate (RRF, RLF) instructions, this bit is loaded with either the high or low-order bit of the source register. 2010 Microchip Technology Inc. Preliminary DS39957B-page 101 PIC18F87K90 FAMILY 6.4 Data Addressing Modes Note: The execution of some instructions in the core PIC18 instruction set are changed when the PIC18 extended instruction set is enabled. For more information, see Section 6.6 “Data Memory and the Extended Instruction Set”. While the program memory can be addressed in only one way, through the program counter, information in the data memory space can be addressed in several ways. For most instructions, the addressing mode is fixed. Other instructions may use up to three modes, depending on which operands are used and whether or not the extended instruction set is enabled. The addressing modes are: • • • • Inherent Literal Direct Indirect An additional addressing mode, Indexed Literal Offset, is available when the extended instruction set is enabled (XINST Configuration bit = 1). For details on this mode’s operation, see Section 6.6.1 “Indexed Addressing with Literal Offset”. 6.4.1 INHERENT AND LITERAL ADDRESSING Many PIC18 control instructions do not need any argument at all. They either perform an operation that globally affects the device or they operate implicitly on one register. This addressing mode is known as Inherent Addressing. Examples of this mode include SLEEP, RESET and DAW. Other instructions work in a similar way, but require an additional explicit argument in the opcode. This method is known as the Literal Addressing mode because the instructions require some literal value as an argument. Examples of this include ADDLW and MOVLW which, respectively, add or move a literal value to the W register. Other examples include CALL and GOTO, which include a 20-bit program memory address. 6.4.2 DIRECT ADDRESSING Direct Addressing specifies all or part of the source and/or destination address of the operation within the opcode itself. The options are specified by the arguments accompanying the instruction. In the core PIC18 instruction set, bit-oriented and byte-oriented instructions use some version of Direct Addressing by default. All of these instructions include some 8-bit literal address as their Least Significant Byte. This address specifies the instruction’s data source as either a register address in one of the banks DS39957B-page 102 of data RAM (see Section 6.3.3 “General Purpose Register File”) or a location in the Access Bank (see Section 6.3.2 “Access Bank”). The Access RAM bit ‘a’ determines how the address is interpreted. When ‘a’ is ‘1’, the contents of the BSR (Section 6.3.1 “Bank Select Register”) are used with the address to determine the complete 12-bit address of the register. When ‘a’ is ‘0’, the address is interpreted as being a register in the Access Bank. Addressing that uses the Access RAM is sometimes also known as Direct Forced Addressing mode. A few instructions, such as MOVFF, include the entire 12-bit address (either source or destination) in their opcodes. In these cases, the BSR is ignored entirely. The destination of the operation’s results is determined by the destination bit, ‘d’. When ‘d’ is ‘1’, the results are stored back in the source register, overwriting its original contents. When ‘d’ is ‘0’, the results are stored in the W register. Instructions without the ‘d’ argument have a destination that is implicit in the instruction, either the target register is being operated on or the W register. 6.4.3 INDIRECT ADDRESSING Indirect Addressing allows the user to access a location in data memory without giving a fixed address in the instruction. This is done by using File Select Registers (FSRs) as pointers to the locations to be read or written to. Since the FSRs are themselves located in RAM as Special Function Registers, they can also be directly manipulated under program control. This makes FSRs very useful in implementing data structures such as tables and arrays in data memory. The registers for Indirect Addressing are also implemented with Indirect File Operands (INDFs) that permit automatic manipulation of the pointer value with auto-incrementing, auto-decrementing or offsetting with another value. This allows for efficient code using loops, such as the example of clearing an entire RAM bank in Example 6-5. It also enables users to perform Indexed Addressing and other Stack Pointer operations for program memory in data memory. EXAMPLE 6-5: NEXT LFSR CLRF BTFSS BRA CONTINUE Preliminary HOW TO CLEAR RAM (BANK 1) USING INDIRECT ADDRESSING FSR0, 100h ; POSTINC0 ; Clear INDF ; register then ; inc pointer FSR0H, 1 ; All done with ; Bank1? NEXT ; NO, clear next ; YES, continue 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 6.4.3.1 FSR Registers and the INDF Operand are mapped in the SFR space, but are not physically implemented. Reading or writing to a particular INDF register actually accesses its corresponding FSR register pair. A read from INDF1, for example, reads the data at the address indicated by FSR1H:FSR1L. At the core of Indirect Addressing are three sets of registers: FSR0, FSR1 and FSR2. Each represents a pair of 8-bit registers: FSRnH and FSRnL. The four upper bits of the FSRnH register are not used, so each FSR pair holds a 12-bit value. This represents a value that can address the entire range of the data memory in a linear fashion. The FSR register pairs, then, serve as pointers to data memory locations. Instructions that use the INDF registers as operands actually use the contents of their corresponding FSR as a pointer to the instruction’s target. The INDF operand is just a convenient way of using the pointer. Because Indirect Addressing uses a full 12-bit address, data RAM banking is not necessary. Thus, the current contents of the BSR and the Access RAM bit have no effect on determining the target address. Indirect Addressing is accomplished with a set of Indirect File Operands, INDF0 through INDF2. These can be thought of as “virtual” registers. The operands FIGURE 6-8: INDIRECT ADDRESSING 000h Using an instruction with one of the Indirect Addressing registers as the operand.... Bank 0 ADDWF, INDF1, 1 100h Bank 1 200h ...uses the 12-bit address stored in the FSR pair associated with that register.... 300h FSR1H:FSR1L 7 0 x x x x 1 1 1 1 7 Bank 2 0 1 1 0 0 1 1 0 0 Bank 3 through Bank 13 ...to determine the data memory location to be used in that operation. E00h In this case, the FSR1 pair contains FCCh. This means the contents of location, FCCh, will be added to that of the W register and stored back in FCCh. Bank 14 F00h FFFh Bank 15 Data Memory 2010 Microchip Technology Inc. Preliminary DS39957B-page 103 PIC18F87K90 FAMILY 6.4.3.2 FSR Registers and POSTINC, POSTDEC, PREINC and PLUSW In addition to the INDF operand, each FSR register pair also has four additional indirect operands. Like INDF, these are “virtual” registers that cannot be indirectly read or written to. Accessing these registers actually accesses the associated FSR register pair, but also performs a specific action on its stored value. These operands are: • POSTDEC – Accesses the FSR value, then automatically decrements it by ‘1’ afterwards • POSTINC – Accesses the FSR value, then automatically increments it by ‘1’ afterwards • PREINC – Increments the FSR value by ‘1’, then uses it in the operation • PLUSW – Adds the signed value of the W register (range of -127 to 128) to that of the FSR and uses the new value in the operation In this context, accessing an INDF register uses the value in the FSR registers without changing them. Similarly, accessing a PLUSW register gives the FSR value, offset by the value in the W register – with neither value actually changed in the operation. Accessing the other virtual registers changes the value of the FSR registers. Operations on the FSRs with POSTDEC, POSTINC and PREINC affect the entire register pair. Rollovers of the FSRnL register, from FFh to 00h, carry over to the FSRnH register. On the other hand, results of these operations do not change the value of any flags in the STATUS register (for example, Z, N and OV bits). The PLUSW register can be used to implement a form of Indexed Addressing in the data memory space. By manipulating the value in the W register, users can reach addresses that are fixed offsets from pointer addresses. In some applications, this can be used to implement some powerful program control structure, such as software stacks, inside of data memory. DS39957B-page 104 6.4.3.3 Operations by FSRs on FSRs Indirect Addressing operations that target other FSRs or virtual registers represent special cases. For example, using an FSR to point to one of the virtual registers will not result in successful operations. As a specific case, assume that the FSR0H:FSR0L registers contain FE7h, the address of INDF1. Attempts to read the value of the INDF1, using INDF0 as an operand, will return 00h. Attempts to write to INDF1, using INDF0 as the operand, will result in a NOP. On the other hand, using the virtual registers to write to an FSR pair may not occur as planned. In these cases, the value will be written to the FSR pair, but without any incrementing or decrementing. Thus, writing to INDF2 or POSTDEC2 will write the same value to the FSR2H:FSR2L. Since the FSRs are physical registers mapped in the SFR space, they can be manipulated through all direct operations. Users should proceed cautiously when working on these registers, however, particularly if their code uses Indirect Addressing. Similarly, operations by Indirect Addressing are generally permitted on all other SFRs. Users should exercise the appropriate caution, so that they do not inadvertently change settings that might affect the operation of the device. 6.5 Program Memory and the Extended Instruction Set The operation of program memory is unaffected by the use of the extended instruction set. Enabling the extended instruction set adds five additional two-word commands to the existing PIC18 instruction set: ADDFSR, CALLW, MOVSF, MOVSS and SUBFSR. These instructions are executed as described in Section 6.2.4 “Two-Word Instructions”. Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 6.6 Data Memory and the Extended Instruction Set 6.6.2 INSTRUCTIONS AFFECTED BY INDEXED LITERAL OFFSET MODE Enabling the PIC18 extended instruction set (XINST Configuration bit = 1) significantly changes certain aspects of data memory and its addressing. Using the Access Bank for many of the core PIC18 instructions introduces a new addressing mode for the data memory space. This mode also alters the behavior of Indirect Addressing using FSR2 and its associated operands. Any of the core PIC18 instructions that can use Direct Addressing are potentially affected by the Indexed Literal Offset Addressing mode. This includes all byte-oriented and bit-oriented instructions, or almost one-half of the standard PIC18 instruction set. Instructions that only use Inherent or Literal Addressing modes are unaffected. What does not change is just as important. The size of the data memory space is unchanged, as well as its linear addressing. The SFR map remains the same. Core PIC18 instructions can still operate in both Direct and Indirect Addressing mode. Inherent and literal instructions do not change at all. Indirect Addressing with FSR0 and FSR1 also remains unchanged. Additionally, byte-oriented and bit-oriented instructions are not affected, if they do not use the Access Bank (Access RAM bit = 1) or include a file address of 60h or above. Instructions meeting these criteria will continue to execute as before. A comparison of the different possible addressing modes when the extended instruction set is enabled is shown in Figure 6-9. 6.6.1 INDEXED ADDRESSING WITH LITERAL OFFSET Enabling the PIC18 extended instruction set changes the behavior of Indirect Addressing using the FSR2 register pair and its associated file operands. Under the proper conditions, instructions that use the Access Bank – that is, most bit-oriented and byte-oriented instructions – can invoke a form of Indexed Addressing using an offset specified in the instruction. This special addressing mode is known as Indexed Addressing with Literal Offset or the Indexed Literal Offset mode. Those who desire to use byte-oriented or bit-oriented instructions in the Indexed Literal Offset mode should note the changes to assembler syntax for this mode. This is described in more detail in Section 29.2.1 “Extended Instruction Syntax”. When using the extended instruction set, this addressing mode requires the following: • Use of the Access Bank (‘a’ = 0) • A file address argument that is less than or equal to 5Fh Under these conditions, the file address of the instruction is not interpreted as the lower byte of an address (used with the BSR in Direct Addressing) or as an 8-bit address in the Access Bank. Instead, the value is interpreted as an offset value to an Address Pointer specified by FSR2. The offset and the contents of FSR2 are added to obtain the target address of the operation. 2010 Microchip Technology Inc. Preliminary DS39957B-page 105 PIC18F87K90 FAMILY FIGURE 6-9: COMPARING ADDRESSING OPTIONS FOR BIT-ORIENTED AND BYTE-ORIENTED INSTRUCTIONS (EXTENDED INSTRUCTION SET ENABLED) EXAMPLE INSTRUCTION: ADDWF, f, d, a (Opcode: 0010 01da ffff ffff) When a = 0 and f 60h: The instruction executes in Direct Forced mode. ‘f’ is interpreted as a location in the Access RAM between 060h and FFFh. This is the same as locations, F60h to FFFh (Bank 15), of data memory. Locations below 060h are not available in this addressing mode. 000h 060h Bank 0 100h 00h Bank 1 through Bank 14 F00h 60h Valid range for ‘f’ Access RAM FFh Bank 15 F40h SFRs FFFh When a = 0 and f5Fh: The instruction executes in Indexed Literal Offset mode. ‘f’ is interpreted as an offset to the address value in FSR2. The two are added together to obtain the address of the target register for the instruction. The address can be anywhere in the data memory space. Note that in this mode, the correct syntax is now: ADDWF [k], d where ‘k’ is the same as ‘f’. When a = 1 (all values of f): The instruction executes in Direct mode (also known as Direct Long mode). ‘f’ is interpreted as a location in one of the 16 banks of the data memory space. The bank is designated by the Bank Select Register (BSR). The address can be in any implemented bank in the data memory space. Data Memory 000h Bank 0 060h 100h 001001da ffffffff Bank 1 through Bank 14 FSR2H FSR2L F00h Bank 15 F40h SFRs FFFh Data Memory BSR 00000000 000h Bank 0 060h 100h Bank 1 through Bank 14 001001da ffffffff F00h Bank 15 F40h SFRs FFFh DS39957B-page 106 Data Memory Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 6.6.3 MAPPING THE ACCESS BANK IN INDEXED LITERAL OFFSET MODE The use of Indexed Literal Offset Addressing mode effectively changes how the lower part of Access RAM (00h to 5Fh) is mapped. Rather than containing just the contents of the bottom part of Bank 0, this mode maps the contents from Bank 0 and a user-defined “window” that can be located anywhere in the data memory space. The value of FSR2 establishes the lower boundary of the addresses mapped into the window, while the upper boundary is defined by FSR2 plus 95 (5Fh). Addresses in the Access RAM above 5Fh are mapped as previously described. (See Section 6.3.2 “Access Bank”.) An example of Access Bank remapping in this addressing mode is shown in Figure 6-10. FIGURE 6-10: Remapping the Access Bank applies only to operations using the Indexed Literal Offset mode. Operations that use the BSR (Access RAM bit = 1) will continue to use Direct Addressing as before. Any Indirect or Indexed Addressing operation that explicitly uses any of the indirect file operands (including FSR2) will continue to operate as standard Indirect Addressing. Any instruction that uses the Access Bank, but includes a register address of greater than 05Fh, will use Direct Addressing and the normal Access Bank map. 6.6.4 BSR IN INDEXED LITERAL OFFSET MODE Although the Access Bank is remapped when the extended instruction set is enabled, the operation of the BSR remains unchanged. Direct Addressing, using the BSR to select the data memory bank, operates in the same manner as previously described. REMAPPING THE ACCESS BANK WITH INDEXED LITERAL OFFSET ADDRESSING Example Situation: ADDWF f, d, a FSR2H:FSR2L = 120h Locations in the region from the FSR2 Pointer (120h) to the pointer plus 05Fh (17Fh) are mapped to the bottom of the Access RAM (000h-05Fh). 000h 05Fh Bank 0 100h 120h 17Fh 200h Window 00h Bank 1 Bank 1 “Window” 5Fh 60h Special Function Registers at F60h through FFFh are mapped to 60h through FFh, as usual. Bank 0 addresses below 5Fh are not available in this mode. They can still be addressed by using the BSR. Not Accessible Bank 2 through Bank 14 SFRs FFh Access Bank F00h Bank 15 F60h FFFh SFRs Data Memory 2010 Microchip Technology Inc. Preliminary DS39957B-page 107 PIC18F87K90 FAMILY NOTES: DS39957B-page 108 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 7.0 FLASH PROGRAM MEMORY 7.1 Table Reads and Table Writes The Flash program memory is readable, writable and erasable during normal operation over the entire VDD range. In order to read and write program memory, there are two operations that allow the processor to move bytes between the program memory space and the data RAM: A read from program memory is executed on one byte at a time. For execution of a write to or erasure of program memory: • Table Read (TBLRD) • Table Write (TBLWT) • Memory of 32 Kbytes and 64 Kbytes (PIC18FX5K90 and PIC18FX6K90 devices) – Blocks of 64 bytes • Memory of 128 Kbytes (PIC18FX7K90 devices) – Blocks of 128 bytes Writing or erasing program memory will cease instruction fetches until the operation is complete. The program memory cannot be accessed during the write or erase, therefore, code cannot execute. An internal programming timer terminates program memory writes and erases. A value written to program memory does not need to be a valid instruction. Executing a program memory location that forms an invalid instruction results in a NOP. FIGURE 7-1: The program memory space is 16 bits wide, while the data RAM space is 8 bits wide. Table reads and table writes move data between these two memory spaces through an 8-bit register (TABLAT). Table read operations retrieve data from program memory and place it into the data RAM space. Figure 7-1 shows the operation of a table read with program memory and data RAM. Table write operations store data from the data memory space into holding registers in program memory. The procedure to write the contents of the holding registers into program memory is detailed in Section 7.5 “Writing to Flash Program Memory”. Figure 7-2 shows the operation of a table write with program memory and data RAM. Table operations work with byte entities. A table block containing data, rather than program instructions, is not required to be word-aligned. Therefore, a table block can start and end at any byte address. If a table write is being used to write executable code into program memory, program instructions will need to be word-aligned. TABLE READ OPERATION Instruction: TBLRD* Program Memory Table Pointer(1) TBLPTRU TBLPTRH Table Latch (8-bit) TBLPTRL TABLAT Program Memory (TBLPTR) Note 1: The Table Pointer register points to a byte in program memory. 2010 Microchip Technology Inc. Preliminary DS39957B-page 109 PIC18F87K90 FAMILY FIGURE 7-2: TABLE WRITE OPERATION Instruction: TBLWT* Program Memory Holding Registers Table Pointer(1) TBLPTRU TBLPTRH Table Latch (8-bit) TBLPTRL TABLAT Program Memory (TBLPTR) Note 1: The Table Pointer actually points to one of 64 holding registers; the address of which is determined by TBLPTRL<5:0>. The process for physically writing data to the program memory array is discussed in Section 7.5 “Writing to Flash Program Memory”. 7.2 Control Registers Several control registers are used in conjunction with the TBLRD and TBLWT instructions. These include the: • • • • EECON1 register EECON2 register TABLAT register TBLPTR registers 7.2.1 EECON1 AND EECON2 REGISTERS The EECON1 register (Register 7-1) is the control register for memory accesses. The EECON2 register, not a physical register, is used exclusively in the memory write and erase sequences. Reading EECON2 will read all ‘0’s. The EEPGD control bit determines if the access is a program or data EEPROM memory access. When clear, any subsequent operations operate on the data EEPROM memory. When set, any subsequent operations operate on the program memory. The FREE bit, when set, allows a program memory erase operation. When FREE is set, the erase operation is initiated on the next WR command. When FREE is clear, only writes are enabled. The WREN bit, when set, allows a write operation. On power-up, the WREN bit is clear. The WRERR bit is set in hardware when the WR bit is set and cleared when the internal programming timer expires and the write operation is complete. Note: The WR control bit initiates write operations. The bit cannot be cleared, only set, in software. It is cleared in hardware at the completion of the write operation. Note: The CFGS control bit determines if the access is to the Configuration/Calibration registers or to program memory/data EEPROM memory. When set, subsequent operations operate on Configuration registers regardless of EEPGD (see Section 28.0 “Special Features of the CPU”). When clear, memory selection access is determined by EEPGD. DS39957B-page 110 During normal operation, the WRERR is read as ‘1’. This can indicate that a write operation was prematurely terminated by a Reset, or a write operation was attempted improperly. Preliminary The EEIF interrupt flag bit (PIR6<4>) is set when the write is complete. It must be cleared in software. 2010 Microchip Technology Inc. PIC18F87K90 FAMILY REGISTER 7-1: R/W-x EEPGD EECON1: EEPROM CONTROL REGISTER 1 R/W-x U-0 R/W-0 R/W-x R/W-0 R/S-0 R/S-0 CFGS — FREE WRERR(1) WREN WR RD bit 7 bit 0 Legend: S = Settable bit R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 EEPGD: Flash Program or Data EEPROM Memory Select bit 1 = Access Flash program memory 0 = Access data EEPROM memory bit 6 CFGS: Flash Program/Data EEPROM or Configuration Select bit 1 = Access Configuration registers 0 = Access Flash program or data EEPROM memory bit 5 Unimplemented: Read as ‘0’ bit 4 FREE: Flash Block Erase Enable bit 1 = Erase the program memory row addressed by TBLPTR on the next WR command (cleared by completion of erase operation) 0 = Perform write-only bit 3 WRERR: Flash Program/Data EEPROM Error Flag bit(1) 1 = A write operation is prematurely terminated (any Reset during self-timed programming in normal operation or an improper write attempt) 0 = The write operation completed bit 2 WREN: Flash Program/Data EEPROM Write Enable bit 1 = Allows write cycles to Flash program/data EEPROM 0 = Inhibits write cycles to Flash program/data EEPROM bit 1 WR: Write-Control bit 1 = Initiates a data EEPROM erase/write cycle, or a program memory erase cycle or write cycle. (The operation is self-timed and the bit is cleared by hardware once write is complete. The WR bit can only be set (not cleared) in software.) 0 = Write cycle to the EEPROM is complete bit 0 RD: Read Control bit 1 = Initiates an EEPROM read (Read takes one cycle. RD is cleared in hardware. The RD bit can only be set (not cleared) in software. RD bit cannot be set when EEPGD = 1 or CFGS = 1.) 0 = Does not initiate an EEPROM read Note 1: When a WRERR occurs, the EEPGD and CFGS bits are not cleared. This allows tracing of the error condition. 2010 Microchip Technology Inc. Preliminary DS39957B-page 111 PIC18F87K90 FAMILY 7.2.2 TABLAT – TABLE LATCH REGISTER 7.2.4 The Table Latch (TABLAT) is an 8-bit register mapped into the SFR space. The Table Latch register is used to hold 8-bit data during data transfers between program memory and data RAM. 7.2.3 TBLPTR is used in reads, writes and erases of the Flash program memory. When a TBLRD is executed, all 22 bits of the TBLPTR determine which byte is read from program memory into TABLAT. TBLPTR – TABLE POINTER REGISTER When a TBLWT is executed, the six LSbs of the Table Pointer register (TBLPTR<5:0>) determine which of the 64 program memory holding registers is written to. When the timed write to program memory begins (via the WR bit), the 16 MSbs of the TBLPTR (TBLPTR<21:6>) determine which program memory block of 64 bytes is written to. For more detail, see Section 7.5 “Writing to Flash Program Memory”. The Table Pointer (TBLPTR) register addresses a byte within the program memory. The TBLPTR is comprised of three SFR registers: Table Pointer Upper Byte, Table Pointer High Byte and Table Pointer Low Byte (TBLPTRU:TBLPTRH:TBLPTRL). These three registers join to form a 22-bit wide pointer. The low-order 21 bits allow the device to address up to 2 Mbytes of program memory space. The 22nd bit allows access to the Device ID, the User ID and the Configuration bits. When an erase of program memory is executed, the 16 MSbs of the Table Pointer register (TBLPTR<21:6>) point to the 64-byte block that will be erased. The Least Significant bits (TBLPTR<5:0>) are ignored. The Table Pointer register, TBLPTR, is used by the TBLRD and TBLWT instructions. These instructions can update the TBLPTR in one of four ways, based on the table operation. These operations are shown in Table 7-1 and only affect the low-order 21 bits. TABLE 7-1: TABLE POINTER BOUNDARIES Figure 7-3 describes the relevant boundaries of TBLPTR based on Flash program memory operations. TABLE POINTER OPERATIONS WITH TBLRD AND TBLWT INSTRUCTIONS Example Operation on Table Pointer TBLRD* TBLWT* TBLPTR is not modified TBLRD*+ TBLWT*+ TBLPTR is incremented after the read/write TBLRD*TBLWT*- TBLPTR is decremented after the read/write TBLRD+* TBLWT+* TBLPTR is incremented before the read/write FIGURE 7-3: 21 TABLE POINTER BOUNDARIES BASED ON OPERATION TBLPTRU 16 15 TBLPTRH 8 TABLE ERASE/WRITE TBLPTR<21:6> 7 TBLPTRL 0 TABLE WRITE TBLPTR<5:0> TABLE READ – TBLPTR<21:0> DS39957B-page 112 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 7.3 Reading the Flash Program Memory The TBLRD instruction is used to retrieve data from program memory and places it into data RAM. Table reads from program memory are performed one byte at a time. FIGURE 7-4: TBLPTR points to a byte address in program space. Executing TBLRD places the byte pointed to into TABLAT. In addition, TBLPTR can be modified automatically for the next table read operation. The internal program memory is typically organized by words. The Least Significant bit of the address selects between the high and low bytes of the word. Figure 7-4 shows the interface between the internal program memory and the TABLAT. READS FROM FLASH PROGRAM MEMORY Program Memory (Even Byte Address) (Odd Byte Address) TBLPTR = xxxxx1 Instruction Register (IR) EXAMPLE 7-1: FETCH TBLRD TBLPTR = xxxxx0 TABLAT Read Register READING A FLASH PROGRAM MEMORY WORD MOVLW MOVWF MOVLW MOVWF MOVLW MOVWF CODE_ADDR_UPPER TBLPTRU CODE_ADDR_HIGH TBLPTRH CODE_ADDR_LOW TBLPTRL ; Load TBLPTR with the base ; address of the word READ_WORD TBLRD*+ MOVF MOVWF TBLRD*+ MOVF MOVF TABLAT, W WORD_EVEN TABLAT, W WORD_ODD 2010 Microchip Technology Inc. ; read into TABLAT and increment ; get data ; read into TABLAT and increment ; get data Preliminary DS39957B-page 113 PIC18F87K90 FAMILY 7.4 Erasing Flash Program Memory The erase block is 32 words or 64 bytes for the PIC18FX5K90 and PIC18FX6K90 devices, and 64 words or 128 bytes for the PIC18FX7K90 devices. Word erase in the Flash array is not supported. When initiating an erase sequence from the microcontroller itself, a block of 64 or 128 bytes of program memory is erased. The Most Significant 16 bits of the TBLPTR<21:6> point to the block being erased. The TBLPTR<5:0> bits are ignored. The EECON1 register commands the erase operation. The EEPGD bit must be set to point to the Flash program memory. The WREN bit must be set to enable write operations. The FREE bit is set to select an erase operation. For protection, the write initiate sequence for EECON2 must be used. A long write is necessary for erasing the internal Flash. Instruction execution is halted while in a long write cycle. The long write will be terminated by the internal programming timer. EXAMPLE 7-2: 7.4.1 FLASH PROGRAM MEMORY ERASE SEQUENCE The sequence of events for erasing a block of internal program memory location is: 1. Load the Table Pointer register with the address of row to be erased. Set the EECON1 register for the erase operation: • Set the EEPGD bit to point to program memory • Clear the CFGS bit to access program memory • Set the WREN bit to enable writes • Set the FREE bit to enable the erase Disable the interrupts. Write 0x55 to EECON2. Write 0xAA to EECON2. Set the WR bit. This begins the row erase cycle. The CPU will stall for the duration of the erase for TIW. (See parameter D133A.) Re-enable interrupts. 2. 3. 4. 5. 6. 7. ERASING A FLASH PROGRAM MEMORY ROW MOVLW MOVWF MOVLW MOVWF MOVLW MOVWF CODE_ADDR_UPPER TBLPTRU CODE_ADDR_HIGH TBLPTRH CODE_ADDR_LOW TBLPTRL ; load TBLPTR with the base ; address of the memory block BSF BCF BSF BSF BCF MOVLW MOVWF MOVLW MOVWF BSF BSF EECON1, EECON1, EECON1, EECON1, INTCON, 0x55 EECON2 0xAA EECON2 EECON1, INTCON, ; ; ; ; ; ERASE_ROW Required Sequence DS39957B-page 114 EEPGD CFGS WREN FREE GIE point to Flash program memory access Flash program memory enable write to memory enable Row Erase operation disable interrupts ; write 55h WR GIE ; write 0AAh ; start erase (CPU stall) ; re-enable interrupts Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 7.5 Writing to Flash Program Memory The programming block is 32 words or 64 bytes for PIC18FX5K90 and PIC18FX6K90 devices, and 64 words or 128 bytes for PIC18FX7K90 devices. Word or byte programming is not supported. Table writes are used internally to load the holding registers needed to program the Flash memory. There are 64 holding registers for PIC18FX5K90 and PIC18FX6K90 devices and 128 holding registers for PIC18FX7K90 used by the table writes for programming. The long write is necessary for programming the internal Flash. Instruction execution is halted while in a long write cycle. The long write is terminated by the internal programming timer. The EEPROM on-chip timer controls the write time. The write/erase voltages are generated by an on-chip charge pump, rated to operate over the voltage range of the device. Note: Since the Table Latch (TABLAT) is only a single byte, the TBLWT instruction may need to be executed 64 times for each programming operation. All of the table write operations will essentially be short writes because only the holding registers are written. At the end of updating the 64 or 128 holding registers, the EECON1 register must be written to in order to start the programming operation with a long write. FIGURE 7-5: The default value of the holding registers on device Resets and after write operations is FFh. A write of FFh to a holding register does not modify that byte. This means that individual bytes of program memory may be modified, provided that the change does not attempt to change any bit from a ‘0’ to a ‘1’. When modifying individual bytes, it is not necessary to load all 64 or 128 holding registers before executing a write operation. TABLE WRITES TO FLASH PROGRAM MEMORY TABLAT Write Register 8 8 TBLPTR = xxxxx0 TBLPTR = xxxxx1 Holding Register 8 TBLPTR = xxxx3F TBLPTR = xxxxx2 Holding Register 8 Holding Register Holding Register Program Memory 7.5.1 FLASH PROGRAM MEMORY WRITE SEQUENCE The sequence of events for programming an internal program memory location should be: 1. 2. 3. 4. 5. 6. 7. 8. 9. Read the 64 or 128 bytes into RAM. Update the data values in RAM as necessary. Load the Table Pointer register with the address being erased. Execute the row erase procedure. Load the Table Pointer register with the address of the first byte being written. Write the 64 or 128 bytes into the holding registers with auto-increment. Set the EECON1 register for the write operation: • Set the EEPGD bit to point to program memory • Clear the CFGS bit to access program memory • Set WREN to enable byte writes Disable the interrupts. Write 0x55 to EECON2. 2010 Microchip Technology Inc. 10. Write 0xAA to EECON2. 11. Set the WR bit. This will begin the write cycle. The CPU will stall for duration of the write for TIW (see parameter D133A). 12. Re-enable the interrupts. 13. Verify the memory (table read). An example of the required code is shown in Example 7-3 on the following page. Note: Before setting the WR bit, the Table Pointer address needs to be within the intended address range of the 64 or 128 bytes in the holding register. Note: Self-write execution to Flash and EEPROM memory cannot be done while running in LP Oscillator mode (Low-Power mode). Therefore, executing a self-write will put the device into High-Power mode. Preliminary DS39957B-page 115 PIC18F87K90 FAMILY EXAMPLE 7-3: WRITING TO FLASH PROGRAM MEMORY MOVLW MOVWF MOVLW MOVWF MOVLW MOVWF MOVLW MOVWF MOVLW MOVWF MOVLW MOVWF SIZE_OF_BLOCK COUNTER BUFFER_ADDR_HIGH FSR0H BUFFER_ADDR_LOW FSR0L CODE_ADDR_UPPER TBLPTRU CODE_ADDR_HIGH TBLPTRH CODE_ADDR_LOW TBLPTRL ; number of bytes in erase block TBLRD*+ MOVF MOVWF DECFSZ BRA TABLAT, W POSTINC0 COUNTER READ_BLOCK MOVLW MOVWF MOVLW MOVWF MOVLW MOVWF MOVLW MOVWF DATA_ADDR_HIGH FSR0H DATA_ADDR_LOW FSR0L NEW_DATA_LOW POSTINC0 NEW_DATA_HIGH INDF0 ; point to buffer CODE_ADDR_UPPER TBLPTRU CODE_ADDR_HIGH TBLPTRH CODE_ADDR_LOW TBLPTRL EECON1, EEPGD EECON1, CFGS EECON1, WREN EECON1, FREE INTCON, GIE 0x55 EECON2 0xAA EECON2 EECON1, WR INTCON, GIE ; load TBLPTR with the base ; address of the memory block ; point to buffer ; Load TBLPTR with the base ; address of the memory block READ_BLOCK ; ; ; ; ; read into TABLAT, and inc get data store data done? repeat MODIFY_WORD ; update buffer word ERASE_BLOCK MOVLW MOVWF MOVLW MOVWF MOVLW MOVWF BSF BCF BSF BSF BCF MOVLW Required MOVWF Sequence MOVLW MOVWF BSF BSF TBLRD*MOVLW MOVWF MOVLW MOVWF WRITE_BUFFER_BACK MOVLW MOVWF WRITE_BYTE_TO_HREGS MOVFF MOVWF TBLWT+* ; ; ; ; ; ; write 55h ; ; ; ; ; BUFFER_ADDR_HIGH FSR0H BUFFER_ADDR_LOW FSR0L write 0AAh start erase (CPU stall) re-enable interrupts dummy read decrement point to buffer SIZE_OF_BLOCK COUNTER ; number of bytes in holding register POSTINC0, WREG TABLAT ; ; ; ; ; DECFSZ COUNTER GOTO WRITE_BYTE_TO_HREGS DS39957B-page 116 point to Flash program memory access Flash program memory enable write to memory enable Row Erase operation disable interrupts get low byte of buffer data present data to table latch write data, perform a short write to internal TBLWT holding register. loop until buffers are full Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY EXAMPLE 7-3: WRITING TO FLASH PROGRAM MEMORY (CONTINUED) PROGRAM_MEMORY BSF BCF BSF BCF MOVLW MOVWF MOVLW MOVWF BSF BSF BCF Required Sequence 7.5.2 EECON1, EECON1, EECON1, INTCON, 0x55 EECON2 0xAA EECON2 EECON1, INTCON, EECON1, EEPGD CFGS WREN GIE ; ; ; ; point to Flash program memory access Flash program memory enable write to memory disable interrupts ; write 55h ; ; ; ; WR GIE WREN write 0AAh start program (CPU stall) re-enable interrupts disable write to memory WRITE VERIFY 7.5.4 Depending on the application, good programming practice may dictate that the value written to the memory should be verified against the original value. This should be used in applications where excessive writes can stress bits near the specification limit. 7.5.3 UNEXPECTED TERMINATION OF WRITE OPERATION If a write is terminated by an unplanned event, such as loss of power or an unexpected Reset, the memory location just programmed should be verified and reprogrammed if needed. If the write operation is interrupted by a MCLR Reset or a WDT Time-out Reset during normal operation, the user can check the WRERR bit and rewrite the location(s) as needed. TABLE 7-2: PROTECTION AGAINST SPURIOUS WRITES To protect against spurious writes to Flash program memory, the write initiate sequence must also be followed. See Section 28.0 “Special Features of the CPU” for more detail. 7.6 Flash Program Operation During Code Protection See Section 28.6 “Program Verification and Code Protection” for details on code protection of Flash program memory. REGISTERS ASSOCIATED WITH PROGRAM FLASH MEMORY Name Bit 7 Bit 6 TBLPTRU — — Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 bit 21(1) Program Memory Table Pointer Upper Byte (TBLPTR<20:16>) Reset Values on Page: 73 TBPLTRH Program Memory Table Pointer High Byte (TBLPTR<15:8>) 73 TBLPTRL Program Memory Table Pointer Low Byte (TBLPTR<7:0>) 73 TABLAT 73 Program Memory Table Latch INTCON GIE/GIEH PEIE/GIEL TMR0IE EECON2 EEPROM Control Register 2 (not a physical register) INT0IE RBIE TMR0IF INT0IF RBIF 73 77 EEPGD CFGS — FREE WRERR WREN WR RD 77 IPR6 — — — EEIP — CMP3IP CMP2IP CMP1IP 75 PIR6 — — — EEIF — CMP3IF CMP2IF CMP1IF 75 PIE6 — — — EEIE — CMP3IE CMP2IE CMP1IE 78 EECON1 Legend: — = unimplemented, read as ‘0’. Shaded cells are not used during Flash/EEPROM access. Note 1: Bit 21 of TBLPTRU allows access to the device Configuration bits. 2010 Microchip Technology Inc. Preliminary DS39957B-page 117 PIC18F87K90 FAMILY NOTES: DS39957B-page 118 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 8.0 DATA EEPROM MEMORY 8.2 The data EEPROM is a nonvolatile memory array, separate from the data RAM and program memory, that is used for long-term storage of program data. The PIC18F87K90 family of devices has a 1024-byte data EEPROM. It is not directly mapped in either the register file or program memory space, but is indirectly addressed through the Special Function Registers (SFRs). The EEPROM is readable and writable during normal operation over the entire VDD range. Five SFRs are used to read and write to the data EEPROM, as well as the program memory. They are: • • • • • EECON1 EECON2 EEDATA EEADR EEADRH The data EEPROM allows byte read and write. When interfacing to the data memory block, EEDATA holds the 8-bit data for read/write and the EEADRH:EEADR register pair holds the address of the EEPROM location being accessed. The EEPROM data memory is rated for high erase/write cycle endurance. A byte write automatically erases the location and writes the new data (erase-before-write). The write time is controlled by an on-chip timer; it will vary with voltage and temperature, as well as from chipto-chip. Please refer to parameter D122 (Table 31-1 in Section 31.0 “Electrical Characteristics”) for exact limits. 8.1 EEADR and EEADRH Registers The EEADRH:EEADR register pair is used to address the data EEPROM for read and write operations. EEADRH holds the two MSbs of the address; the upper 6 bits are ignored. The 10-bit range of the pair can address a memory range of 1024 bytes (00h to 3FFh). EECON1 and EECON2 Registers Access to the data EEPROM is controlled by two registers: EECON1 and EECON2. These are the same registers which control access to the program memory and are used in a similar manner for the data EEPROM. The EECON1 register (Register 8-1) is the control register for data and program memory access. Control bit, EEPGD, determines if the access will be to program memory or data EEPROM memory. When clear, operations will access the data EEPROM memory. When set, program memory is accessed. Control bit, CFGS, determines if the access will be to the Configuration registers or to program memory/data EEPROM memory. When set, subsequent operations access Configuration registers. When CFGS is clear, the EEPGD bit selects either program Flash or data EEPROM memory. The WREN bit, when set, will allow a write operation. On power-up, the WREN bit is clear. The WRERR bit is set in hardware when the WREN bit is set, and cleared, when the internal programming timer expires and the write operation is complete. Note: During normal operation, the WRERR is read as ‘1’. This can indicate that a write operation was prematurely terminated by a Reset or a write operation was attempted improperly. The WR control bit initiates write operations. The bit cannot be cleared, only set, in software; it is cleared in hardware at the completion of the write operation. Note: The EEIF interrupt flag bit (PIR6<4>) is set when the write is complete. It must be cleared in software. Control bits, RD and WR, start read and erase/write operations, respectively. These bits are set by firmware and cleared by hardware at the completion of the operation. The RD bit cannot be set when accessing program memory (EEPGD = 1). Program memory is read using table read instructions. See Section 7.1 “Table Reads and Table Writes” regarding table reads. The EECON2 register is not a physical register. It is used exclusively in the memory write and erase sequences. Reading EECON2 will read all ‘0’s. 2010 Microchip Technology Inc. Preliminary DS39957B-page 119 PIC18F87K90 FAMILY REGISTER 8-1: R/W-x EEPGD EECON1: DATA EEPROM CONTROL REGISTER 1 R/W-x U-0 R/W-0 R/W-x R/W-0 R/S-0 R/S-0 CFGS — FREE WRERR(1) WREN WR RD bit 7 bit 0 Legend: S = Settable bit R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 EEPGD: Flash Program or Data EEPROM Memory Select bit 1 = Access Flash program memory 0 = Access data EEPROM memory bit 6 CFGS: Flash Program/Data EEPROM or Configuration Select bit 1 = Access Configuration registers 0 = Access Flash program or data EEPROM memory bit 5 Unimplemented: Read as ‘0’ bit 4 FREE: Flash Row Erase Enable bit 1 = Erase the program memory row addressed by the TBLPTR on the next WR command (cleared by completion of an erase operation) 0 = Perform write-only bit 3 WRERR: Flash Program/Data EEPROM Error Flag bit(1) 1 = A write operation is prematurely terminated (any Reset during self-timed programming in normal operation or an improper write attempt) 0 = The write operation completed bit 2 WREN: Flash Program/Data EEPROM Write Enable bit 1 = Allows write cycles to Flash program/data EEPROM 0 = Inhibits write cycles to Flash program/data EEPROM bit 1 WR: Write-Control bit 1 = Initiates a data EEPROM erase/write cycle or a program memory erase cycle or write cycle. (The operation is self-timed and the bit is cleared by hardware once the write is complete. The WR bit can only be set (not cleared) in software.) 0 = Write cycle to the EEPROM is complete bit 0 RD: Read Control bit 1 = Initiates an EEPROM read (Read takes one cycle. RD is cleared in hardware. The RD bit can only be set (not cleared) in software. The RD bit cannot be set when EEPGD = 1 or CFGS = 1.) 0 = Does not initiate an EEPROM read Note 1: When a WRERR occurs, the EEPGD and CFGS bits are not cleared. This allows tracing of the error condition. DS39957B-page 120 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 8.3 Reading the Data EEPROM Memory To read a data memory location, the user must write the address to the EEADRH:EEADR register pair, clear the EEPGD control bit (EECON1<7>) and then set control bit, RD (EECON1<0>). After one cycle, the data is available in the EEDATA register; therefore, it can be read after one NOP instruction. EEDATA will hold this value until another read operation, or until it is written to by the user (during a write operation). The basic process is shown in Example 8-1. 8.4 Writing to the Data EEPROM Memory To write an EEPROM data location, the address must first be written to the EEADRH:EEADR register pair and the data written to the EEDATA register. The sequence in Example 8-2 must be followed to initiate the write cycle. The write will not begin if this sequence is not exactly followed (write 0x55 to EECON2, write 0xAA to EECON2, then set WR bit) for each byte. It is strongly recommended that interrupts be disabled during this code segment. execution (i.e., runaway programs). The WREN bit should be kept clear at all times, except when updating the EEPROM. The WREN bit is not cleared by hardware. After a write sequence has been initiated, EECON1, EEADRH:EEADR and EEDATA cannot be modified. The WR bit will be inhibited from being set unless the WREN bit is set. The WREN bit must be set on a previous instruction. Both WR and WREN cannot be set with the same instruction. At the completion of the write cycle, the WR bit is cleared in hardware and the EEPROM Interrupt Flag bit (EEIF) is set. The user may either enable this interrupt, or poll this bit. EEIF must be cleared by software. 8.5 Write Verify Depending on the application, good programming practice may dictate that the value written to the memory should be verified against the original value. This should be used in applications where excessive writes can stress bits near the specification limit. Note: Additionally, the WREN bit in EECON1 must be set to enable writes. This mechanism prevents accidental writes to data EEPROM due to unexpected code EXAMPLE 8-1: MOVLW MOVWF MOVLW MOVWF BCF BCF BSF NOP MOVF EXAMPLE 8-2: Required Sequence Self-write execution to Flash and EEPROM memory cannot be done while running in LP Oscillator mode (Low-Power mode). Therefore, executing a self-write will put the device into High-Power mode. DATA EEPROM READ DATA_EE_ADDRH EEADRH DATA_EE_ADDR EEADR EECON1, EEPGD EECON1, CFGS EECON1, RD ; ; ; ; ; ; ; EEDATA, W ; W = EEDATA Upper bits of Data Memory Address to read Lower bits of Data Memory Address to read Point to DATA memory Access EEPROM EEPROM Read DATA EEPROM WRITE MOVLW MOVWF MOVLW MOVWF MOVLW MOVWF BCF BCF BSF DATA_EE_ADDRH EEADRH DATA_EE_ADDR EEADR DATA_EE_DATA EEDATA EECON1, EEPGD EECON1, CFGS EECON1, WREN BCF MOVLW MOVWF MOVLW MOVWF BTFSC GOTO BSF INTCON, GIE 0x55 EECON2 0xAA EECON2 EECON1, WR $-2 INTCON, GIE BCF EECON1, WREN 2010 Microchip Technology Inc. ; ; ; ; ; ; ; ; ; Upper bits of Data Memory Address to write Lower bits of Data Memory Address to write Data Memory Value to write Point to DATA memory Access EEPROM Enable writes ; Disable Interrupts ; ; Write 55h ; ; Write 0AAh ; Wait for write to complete ; Enable Interrupts ; User code execution ; Disable writes on write complete (EEIF set) Preliminary DS39957B-page 121 PIC18F87K90 FAMILY 8.6 Operation During Code-Protect 8.8 Data EEPROM memory has its own code-protect bits in Configuration Words. External read and write operations are disabled if code protection is enabled. The microcontroller itself can both read and write to the internal data EEPROM regardless of the state of the code-protect Configuration bit. Refer to Section 28.0 “Special Features of the CPU” for additional information. 8.7 Protection Against Spurious Write There are conditions when the device may not want to write to the data EEPROM memory. To protect against spurious EEPROM writes, various mechanisms have been implemented. On power-up, the WREN bit is cleared. In addition, writes to the EEPROM are blocked during the Power-up Timer period (TPWRT, parameter 33). Using the Data EEPROM The data EEPROM is a high-endurance, byte addressable array that has been optimized for the storage of frequently changing information (e.g., program variables or other data that are updated often). Frequently changing values will typically be updated more often than specification, D124. If this is not the case, an array refresh must be performed. For this reason, variables that change infrequently (such as constants, IDs, calibration, etc.) should be stored in Flash program memory. A simple data EEPROM refresh routine is shown in Example 8-3. Note: If data EEPROM is only used to store constants and/or data that changes often, an array refresh is likely not required. See specification, D124. The write initiate sequence, and the WREN bit together, help prevent an accidental write during brown-out, power glitch or software malfunction. The WREN bit is not cleared by hardware. EXAMPLE 8-3: DATA EEPROM REFRESH ROUTINE CLRF CLRF BCF BCF BCF BSF EEADR EEADRH EECON1, EECON1, INTCON, EECON1, BSF MOVLW MOVWF MOVLW MOVWF BSF BTFSC BRA INCFSZ BRA INCFSZ BRA EECON1, RD 0x55 EECON2 0xAA EECON2 EECON1, WR EECON1, WR $-2 EEADR, F LOOP EEADRH, F LOOP BCF BSF EECON1, WREN INTCON, GIE CFGS EEPGD GIE WREN LOOP DS39957B-page 122 ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; Start at address 0 Set for memory Set for Data EEPROM Disable interrupts Enable writes Loop to refresh array Read current address Write 55h Write 0AAh Set WR bit to begin write Wait for write to complete Increment Not zero, Increment Not zero, address do it again the high address do it again ; Disable writes ; Enable interrupts Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY TABLE 8-1: Name INTCON EEADRH REGISTERS ASSOCIATED WITH DATA EEPROM MEMORY Bit 7 Bit 6 GIE/GIEH PEIE/GIEL — — Bit 5 Bit 4 Bit 3 Bit 2 TMR0IE INT0IE RBIE TMR0IF — — — — Bit 1 Bit 0 INT0IF RBIF EEPROM Address Register High Byte Reset Values on Page: 73 77 EEADR EEPROM Address Register Low Byte 78 EEDATA EEPROM Data Register 78 EECON2 EEPROM Control Register 2 (not a physical register) EECON1 EEPGD CFGS — FREE WRERR 77 WREN WR RD 77 Legend: — = unimplemented, read as ‘0’. Shaded cells are not used during Flash/EEPROM access. 2010 Microchip Technology Inc. Preliminary DS39957B-page 123 PIC18F87K90 FAMILY NOTES: DS39957B-page 124 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 9.0 8 x 8 HARDWARE MULTIPLIER 9.1 Introduction EXAMPLE 9-1: MOVF MULWF All PIC18 devices include an 8 x 8 hardware multiplier as part of the ALU. The multiplier performs an unsigned operation and yields a 16-bit result that is stored in the product register pair, PRODH:PRODL. The multiplier’s operation does not affect any flags in the STATUS register. ARG1, W ARG2 ; ; ARG1 * ARG2 -> ; PRODH:PRODL EXAMPLE 9-2: Making multiplication a hardware operation allows it to be completed in a single instruction cycle. This has the advantages of higher computational throughput and reduced code size for multiplication algorithms and allows PIC18 devices to be used in many applications previously reserved for digital-signal processors. A comparison of various hardware and software multiply operations, along with the savings in memory and execution time, is shown in Table 9-1. 9.2 8 x 8 UNSIGNED MULTIPLY ROUTINE 8 x 8 SIGNED MULTIPLY ROUTINE MOVF MULWF ARG1, W ARG2 BTFSC SUBWF ARG2, SB PRODH, F MOVF BTFSC SUBWF ARG2, W ARG1, SB PRODH, F ; ; ; ; ; ARG1 * ARG2 -> PRODH:PRODL Test Sign Bit PRODH = PRODH - ARG1 ; Test Sign Bit ; PRODH = PRODH ; - ARG2 Operation Example 9-1 shows the instruction sequence for an 8 x 8 unsigned multiplication. Only one instruction is required when one of the arguments is already loaded in the WREG register. Example 9-2 shows the sequence to do an 8 x 8 signed multiplication. To account for the sign bits of the arguments, each argument’s Most Significant bit (MSb) is tested and the appropriate subtractions are done. TABLE 9-1: Routine 8 x 8 unsigned 8 x 8 signed 16 x 16 unsigned 16 x 16 signed PERFORMANCE COMPARISON FOR VARIOUS MULTIPLY OPERATIONS Multiply Method Without hardware multiply Program Cycles Memory (Max) (Words) 13 Time @ 64 MHz @ 48 MHz @ 10 MHz @ 4 MHz 69 4.3 s 5.7 s 27.6 s 69 s Hardware multiply 1 1 62.5 ns 83.3 ns 400 ns 1 s Without hardware multiply 33 91 5.6 s 7.5 s 36.4 s 91 s Hardware multiply 6 6 375 ns 500 ns 2.4 s 6 s Without hardware multiply 21 242 15.1 s 20.1 s 96.8 s 242 s Hardware multiply 28 28 1.7 s 2.3 s 11.2 s 28 s Without hardware multiply 52 254 15.8 s 21.2 s 101.6 s 254 s Hardware multiply 35 40 2.5 s 3.3 s 16.0 s 40 s 2010 Microchip Technology Inc. Preliminary DS39957B-page 125 PIC18F87K90 FAMILY Example 9-3 shows the sequence to do a 16 x 16 unsigned multiplication. Equation 9-1 shows the algorithm that is used. The 32-bit result is stored in four registers (RES3:RES0). EQUATION 9-1: RES3:RES0 = = EXAMPLE 9-3: 16 x 16 UNSIGNED MULTIPLICATION ALGORITHM ARG1H:ARG1L ARG2H:ARG2L (ARG1H ARG2H 216) + (ARG1H ARG2L 28) + (ARG1L ARG2H 28) + (ARG1L ARG2L) EQUATION 9-2: RES3:RES0= = MOVF MULWF ARG1L, W ARG2L MOVFF MOVFF PRODH, RES1 PRODL, RES0 MOVF MULWF ARG1H, W ARG2H MOVFF MOVFF PRODH, RES3 PRODL, RES2 MOVF MULWF ARG1L, W ARG2H MOVF MULWF MOVF ADDWF MOVF ADDWFC CLRF ADDWFC PRODL, W RES1, F PRODH, W RES2, F WREG RES3, F MOVF MULWF ARG1H, W ARG2L MOVF ADDWF MOVF ADDWFC CLRF ADDWFC PRODL, W RES1, F PRODH, W RES2, F WREG RES3, F ; ARG1L * ARG2L-> ; PRODH:PRODL ; ; ; ARG1H * ARG2H-> ; PRODH:PRODL ; ; ARG1L * ARG2H-> PRODH:PRODL ARG1H * ARG2L-> PRODH:PRODL MOVF MULWF ARG1H, W ARG2H MOVFF MOVFF ; ARG1H * ARG2H -> ; PRODH:PRODL PRODH, RES3 ; PRODL, RES2 ; MOVF MULWF ARG1L, W ARG2H MOVF ADDWF MOVF ADDWFC CLRF ADDWFC PRODL, W RES1, F PRODH, W RES2, F WREG RES3, F MOVF MULWF ARG1H, W ARG2L MOVF ADDWF MOVF ADDWFC CLRF ADDWFC PRODL, W RES1, F PRODH, W RES2, F WREG RES3, F ; ; ; ; ; ; ; ; ARG1L * ARG2H -> PRODH:PRODL Add cross products ; ; ; ; ; ; ; ; ; ARG1H * ARG2L -> PRODH:PRODL Add cross products ; Add cross products Example 9-4 shows the sequence to do a 16 x 16 signed multiply. Equation 9-2 shows the algorithm used. The 32-bit result is stored in four registers (RES3:RES0). To account for the sign bits of the arguments, the MSb for each argument pair is tested and the appropriate subtractions are done. DS39957B-page 126 MOVFF MOVFF ; ARG1L * ARG2L -> ; PRODH:PRODL PRODH, RES1 ; PRODL, RES0 ; ; ; ; ; ; ; ; ; ; ; ; ARG1L, W ARG2L ; ; Add cross products 16 x 16 SIGNED MULTIPLY ROUTINE ; ; ; ; ; ; ; ; ; ; ARG1H:ARG1L ARG2H:ARG2L (ARG1H ARG2H 216) + (ARG1H ARG2L 28) + (ARG1L ARG2H 28) + (ARG1L ARG2L) + (-1 ARG2H<7> ARG1H:ARG1L 216) + (-1 ARG1H<7> ARG2H:ARG2L 216) EXAMPLE 9-4: 16 x 16 UNSIGNED MULTIPLY ROUTINE 16 x 16 SIGNED MULTIPLICATION ALGORITHM BTFSS ARG2H, 7 BRA SIGN_ARG1 MOVF ARG1L, W SUBWF RES2 MOVF ARG1H, W SUBWFB RES3 SIGN_ARG1 BTFSS ARG1H, 7 BRA CONT_CODE MOVF ARG2L, W SUBWF RES2 MOVF ARG2H, W SUBWFB RES3 ; CONT_CODE : Preliminary ; ARG2H:ARG2L neg? ; no, check ARG1 ; ; ; ; ; ARG1H:ARG1L neg? ; no, done ; ; ; 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 10.0 INTERRUPTS Members of the PIC18F87K90 family of devices have multiple interrupt sources and an interrupt priority feature that allows most interrupt sources to be assigned a high-priority level or a low-priority level. The high-priority interrupt vector is at 0008h and the low-priority interrupt vector is at 0018h. High-priority interrupt events will interrupt any low-priority interrupts that may be in progress. The registers for controlling interrupt operation are: • • • • • • • RCON INTCON INTCON2 INTCON3 PIR1, PIR2, PIR3 PIE1, PIE2, PIE3 IPR1, IPR2, IPR3 It is recommended that the Microchip header files supplied with MPLAB® IDE be used for the symbolic bit names in these registers. This allows the assembler/compiler to automatically take care of the placement of these bits within the specified register. In general, interrupt sources have three bits to control their operation. They are: • Flag bit – Indicating that an interrupt event occurred • Enable bit – Enabling program execution to branch to the interrupt vector address when the flag bit is set • Priority bit – Specifying high priority or low priority The interrupt priority feature is enabled by setting the IPEN bit (RCON<7>). When interrupt priority is enabled, there are two bits that enable interrupts globally. Setting the GIEH bit (INTCON<7>) enables all interrupts that have the priority bit set (high priority). Setting the GIEL bit (INTCON<6>) enables all interrupts that have the priority bit cleared (low priority). When the interrupt flag, enable bit and appropriate global interrupt enable bit are set, the interrupt will vector immediately to address 0008h or 0018h, depending on the priority bit setting. Individual interrupts can be disabled through their corresponding enable bits. 2010 Microchip Technology Inc. When the IPEN bit is cleared (default state), the interrupt priority feature is disabled and interrupts are compatible with PIC® mid-range devices. In Compatibility mode, the interrupt priority bits for each source have no effect. INTCON<6> is the PEIE bit that enables/disables all peripheral interrupt sources. INTCON<7> is the GIE bit that enables/disables all interrupt sources. All interrupts branch to address 0008h in Compatibility mode. When an interrupt is responded to, the global interrupt enable bit is cleared to disable further interrupts. If the IPEN bit is cleared, this is the GIE bit. If interrupt priority levels are used, this will be either the GIEH or GIEL bit. High-priority interrupt sources can interrupt a low-priority interrupt. Low-priority interrupts are not processed while high-priority interrupts are in progress. The return address is pushed onto the stack and the PC is loaded with the interrupt vector address (0008h or 0018h). Once in the Interrupt Service Routine, the source(s) of the interrupt can be determined by polling the interrupt flag bits. The interrupt flag bits must be cleared in software before re-enabling interrupts to avoid recursive interrupts. The “return from interrupt” instruction, RETFIE, exits the interrupt routine and sets the GIE bit (GIEH or GIEL if priority levels are used) that re-enables interrupts. For external interrupt events, such as the INTx pins or the PORTB input change interrupt, the interrupt latency will be three to four instruction cycles. The exact latency is the same for one or two-cycle instructions. Individual interrupt flag bits are set regardless of the status of their corresponding enable bit or the GIE bit. Note: Preliminary Do not use the MOVFF instruction to modify any of the Interrupt Control registers while any interrupt is enabled. Doing so may cause erratic microcontroller behavior. DS39957B-page 127 PIC18F87K90 FAMILY FIGURE 10-1: PIC18F87K90 FAMILY INTERRUPT LOGIC PIR1<6:0> PIE1<6:0> IPR1<6:0> PIR2<7,5:0> PIE2<7,5:0> IPR2<7:7,5:0> PIR3<6:0> PIE3<6:0> IPR3<6:0> PIR3<7:0> PIE3<7:0> IPR3<7:0> PIR5<7:0> PIE5<7:0> IPR5<7:0> Wake-up if in Idle or Sleep modes TMR0IF TMR0IE TMR0IP RBIF RBIE RBIP INT0IF INT0IE INT1IF INT1IE INT1IP INT2IF INT2IE INT2IP INT3IF INT3IE INT3IP Interrupt to CPU Vector to Location 0008h GIE/GIEH IPEN PIR6<4,2:0> PIE6<4,2:0> IPR6<4,2:0> IPEN PEIE/GIEL IPEN High-Priority Interrupt Generation Low-Priority Interrupt Generation PIR1<6:0> PIE1<6:0> IPR1<6:0> PIR2<7,5:0> PIE2<7,5:0> IPR2<7,5:0> PIR3<7:0> PIE3<7:0> IPR3<7:0> PIR4<7:0> PIE4<7:0> IPR4<7:0> PIR5<7:0> PIE5<7:0> IPR5<7:0> PIR6<4,2:0> PIE6<4,2:0> IPR6<4,2:0> DS39957B-page 128 TMR0IF TMR0IE TMR0IP RBIF RBIE RBIP INT1IF INT1IE INT1IP INT2IF INT2IE INT2IP INT3IF INT3IE INT3IP Preliminary Interrupt to CPU Vector to Location 0018h IPEN GIE/GIEH PEIE/GIEL 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 10.1 INTCON Registers Note: The INTCON registers are readable and writable registers that contain various enable, priority and flag bits. REGISTER 10-1: Interrupt flag bits are set when an interrupt condition occurs regardless of the state of its corresponding enable bit or the global interrupt enable bit. User software should ensure the appropriate interrupt flag bits are clear prior to enabling an interrupt. This feature allows for software polling. INTCON: INTERRUPT CONTROL REGISTER R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-x GIE/GIEH PEIE/GIEL TMR0IE INT0IE RBIE TMR0IF INT0IF RBIF(1) bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 GIE/GIEH: Global Interrupt Enable bit When IPEN = 0: 1 = Enables all unmasked interrupts 0 = Disables all interrupts When IPEN = 1: 1 = Enables all high-priority interrupts 0 = Disables all interrupts bit 6 PEIE/GIEL: Peripheral Interrupt Enable bit When IPEN = 0: 1 = Enables all unmasked peripheral interrupts 0 = Disables all peripheral interrupts When IPEN = 1: 1 = Enables all low-priority peripheral interrupts 0 = Disables all low-priority peripheral interrupts bit 5 TMR0IE: TMR0 Overflow Interrupt Enable bit 1 = Enables the TMR0 overflow interrupt 0 = Disables the TMR0 overflow interrupt bit 4 INT0IE: INT0 External Interrupt Enable bit 1 = Enables the INT0 external interrupt 0 = Disables the INT0 external interrupt bit 3 RBIE: RB Port Change Interrupt Enable bit 1 = Enables the RB port change interrupt 0 = Disables the RB port change interrupt bit 2 TMR0IF: TMR0 Overflow Interrupt Flag bit 1 = TMR0 register has overflowed (must be cleared in software) 0 = TMR0 register did not overflow bit 1 INT0IF: INT0 External Interrupt Flag bit 1 = The INT0 external interrupt occurred (must be cleared in software) 0 = The INT0 external interrupt did not occur bit 0 RBIF: RB Port Change Interrupt Flag bit(1) 1 = At least one of the RB<7:4> pins changed state (must be cleared in software) 0 = None of the RB<7:4> pins have changed state Note 1: A mismatch condition will continue to set this bit. Reading PORTB, and then waiting one additional instruction cycle, will end the mismatch condition and allow the bit to be cleared. 2010 Microchip Technology Inc. Preliminary DS39957B-page 129 PIC18F87K90 FAMILY REGISTER 10-2: INTCON2: INTERRUPT CONTROL REGISTER 2 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 RBPU INTEDG0 INTEDG1 INTEDG2 INTEDG3 TMR0IP INT3IP RBIP bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7 RBPU: PORTB Pull-up Enable bit 1 = All PORTB pull-ups are disabled 0 = PORTB pull-ups are enabled by individual port latch values bit 6 INTEDG0: External Interrupt 0 Edge Select bit 1 = Interrupt on rising edge 0 = Interrupt on falling edge bit 5 INTEDG1: External Interrupt 1 Edge Select bit 1 = Interrupt on rising edge 0 = Interrupt on falling edge bit 4 INTEDG2: External Interrupt 2 Edge Select bit 1 = Interrupt on rising edge 0 = Interrupt on falling edge bit 3 INTEDG3: External Interrupt 3 Edge Select bit 1 = Interrupt on rising edge 0 = Interrupt on falling edge bit 2 TMR0IP: TMR0 Overflow Interrupt Priority bit 1 = High priority 0 = Low priority bit 1 INT3IP: INT3 External Interrupt Priority bit 1 = High priority 0 = Low priority bit 0 RBIP: RB Port Change Interrupt Priority bit 1 = High priority 0 = Low priority Note: x = Bit is unknown Interrupt flag bits are set when an interrupt condition occurs regardless of the state of its corresponding enable bit or the global interrupt enable bit. User software should ensure the appropriate interrupt flag bits are clear prior to enabling an interrupt. This feature allows for software polling. DS39957B-page 130 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY REGISTER 10-3: INTCON3: INTERRUPT CONTROL REGISTER 3 R/W-1 R/W-1 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 INT2IP INT1IP INT3IE INT2IE INT1IE INT3IF INT2IF INT1IF bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7 INT2IP: INT2 External Interrupt Priority bit 1 = High priority 0 = Low priority bit 6 INT1IP: INT1 External Interrupt Priority bit 1 = High priority 0 = Low priority bit 5 INT3IE: INT3 External Interrupt Enable bit 1 = Enables the INT3 external interrupt 0 = Disables the INT3 external interrupt bit 4 INT2IE: INT2 External Interrupt Enable bit 1 = Enables the INT2 external interrupt 0 = Disables the INT2 external interrupt bit 3 INT1IE: INT1 External Interrupt Enable bit 1 = Enables the INT1 external interrupt 0 = Disables the INT1 external interrupt bit 2 INT3IF: INT3 External Interrupt Flag bit 1 = The INT3 external interrupt occurred (must be cleared in software) 0 = The INT3 external interrupt did not occur bit 1 INT2IF: INT2 External Interrupt Flag bit 1 = The INT2 external interrupt occurred (must be cleared in software) 0 = The INT2 external interrupt did not occur bit 0 INT1IF: INT1 External Interrupt Flag bit 1 = The INT1 external interrupt occurred (must be cleared in software) 0 = The INT1 external interrupt did not occur Note: x = Bit is unknown Interrupt flag bits are set when an interrupt condition occurs regardless of the state of its corresponding enable bit or the global interrupt enable bit. User software should ensure the appropriate interrupt flag bits are clear prior to enabling an interrupt. This feature allows for software polling. 2010 Microchip Technology Inc. Preliminary DS39957B-page 131 PIC18F87K90 FAMILY 10.2 PIR Registers The PIR registers contain the individual flag bits for the peripheral interrupts. Due to the number of peripheral interrupt sources, there are six Peripheral Interrupt Request (Flag) registers (PIR1 through PIR6). REGISTER 10-4: Note 1: Interrupt flag bits are set when an interrupt condition occurs regardless of the state of its corresponding enable bit or the Global Interrupt Enable bit, GIE (INTCON<7>). 2: User software should ensure the appropriate interrupt flag bits are cleared prior to enabling an interrupt and after servicing that interrupt. PIR1: PERIPHERAL INTERRUPT REQUEST (FLAG) REGISTER 1 U-0 R/W-0 R-0 R-0 R/W-0 R/W-0 R/W-0 R/W-0 — ADIF RC1IF TX1IF SSP1IF TMR1GIF TMR2IF TMR1IF bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 Unimplemented: Read as ‘0’ bit 6 ADIF: A/D Converter Interrupt Flag bit 1 = An A/D conversion completed (must be cleared in software) 0 = The A/D conversion is not complete bit 5 RC1IF: EUSART Receive Interrupt Flag bit 1 = The EUSART receive buffer, RCREG1, is full (cleared when RCREG1 is read) 0 = The EUSART receive buffer is empty bit 4 TX1IF: EUSART Transmit Interrupt Flag bit 1 = The EUSART transmit buffer, TXREG1, is empty (cleared when TXREG1 is written) 0 = The EUSART transmit buffer is full bit 3 SSP1IF: Master Synchronous Serial Port Interrupt Flag bit 1 = The transmission/reception is complete (must be cleared in software) 0 = Waiting to transmit/receive bit 2 TMR1GIF: Timer1 Gate Interrupt Flag bit 1 = Timer gate interrupt has occurred (must be cleared in software) 0 = No timer gate interrupt has occurred bit 1 TMR2IF: TMR2 to PR2 Match Interrupt Flag bit 1 = TMR2 to PR2 match has occurred (must be cleared in software) 0 = No TMR2 to PR2 match has occurred bit 0 TMR1IF: TMR1 Overflow Interrupt Flag bit 1 = TMR1 register overflowed (must be cleared in software) 0 = TMR1 register did not overflow DS39957B-page 132 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY REGISTER 10-5: PIR2: PERIPHERAL INTERRUPT REQUEST (FLAG) REGISTER 2 R/W-0 U-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 OSCFIF — SSP2IF BCL2IF BCL1IF HLVDIF TMR3IF TMR3GIF bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 OSCFIF: Oscillator Fail Interrupt Flag bit 1 = Device oscillator failed, clock input has changed to INTOSC (must be cleared in software) 0 = Device clock operating bit 6 Unimplemented: Read as ‘0’ bit 5 SSP2IF: Master Synchronous Serial Port Interrupt Flag bit 1 = The transmission/reception has been completed. (must be cleared in software) 0 = Waiting to transmit/receive bit 4 BCL2IF: Bus Collision Interrupt Flag bit 1 = A bus collision occurred (must be cleared in software) 0 = No bus collision occurred bit 3 BCL1IF: Bus Collision Interrupt Flag bit 1 = A bus collision occurred (must be cleared in software) 0 = No bus collision occurred bit 2 HLVDIF: High/Low-Voltage Detect Interrupt Flag bit 1 = A high/low-voltage condition occurred (must be cleared in software) 0 = The device voltage is above the regulator’s low-voltage trip point bit 1 TMR3IF: TMR3 Overflow Interrupt Flag bit 1 = TMR3 register overflowed (must be cleared in software) 0 = TMR3 register did not overflow bit 0 TMR3GIF: TMR3 Gate Interrupt Flag bit 1 = Timer gate interrupt occurred (must be cleared in software) 0 = No timer gate interrupt occurred 2010 Microchip Technology Inc. Preliminary DS39957B-page 133 PIC18F87K90 FAMILY REGISTER 10-6: PIR3: PERIPHERAL INTERRUPT REQUEST (FLAG) REGISTER 3 R/W-0 R/W-0 R-0 R-0 R/W-0 R/W-0 R/W-0 R/W-0 TMR5GIF LCDIF RC2IF TX2IF CTMUIF CCP2IF CCP1IF RTCCIF bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 TMR5GIF: Timer5 Gate Interrupt Flag bit 1 = Timer gate interrupt occured (must be cleared in software) 0 = No timer gate interrupt occured bit 6 LCDIF: LCD Interrupt Flag bit (valid when Type-B waveform with Non-Static mode is selected) 1 = LCD data of all COMs is output (must be cleared in software) 0 = LCD data of all COMs is not yet output bit 5 RC2IF: EUSART Receive Interrupt Flag bit 1 = The EUSART receive buffer, RCREG2, is full (cleared when RCREG2 is read) 0 = The EUSART receive buffer is empty bit 4 TX2IF: EUSART Transmit Interrupt Flag bit 1 = The EUSART transmit buffer, TXREG2, is empty (cleared when TXREG2 is written) 0 = The EUSART transmit buffer is full bit 3 CTMUIF: CTMU Interrupt Flag bit 1 = CTMU interrupt occured (must be cleared in software) 0 = No CTMU interrupt occured bit 2 CCP2IF: ECCP2 Interrupt Flag bit Capture mode: 1 = A TMR register capture occurred (must be cleared in software) 0 = No TMR register capture occurred Compare mode: 1 = A TMR register compare match occurred (must be cleared in software) 0 = No TMR register compare match occurred PWM mode: Unused in this mode. bit 1 CCP1IF: ECCP1 Interrupt Flag bit Capture mode: 1 = A TMR register capture occurred (must be cleared in software) 0 = No TMR register capture occurred Compare mode: 1 = A TMR register compare match occurred (must be cleared in software) 0 = No TMR register compare match occurred PWM mode: Unused in this mode. bit 0 RTCCIF: RTCC Interrupt Flag bit 1 = RTCC interrupt occured (must be cleared in software) 0 = No RTCC interrupt occured DS39957B-page 134 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY REGISTER 10-7: R/W-0 CCP10IF (1) PIR4: PERIPHERAL INTERRUPT FLAG REGISTER 4 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 CCP9IF(1) CCP8IF CCP7IF CCP6IF CCP5IF CCP4IF CCP3IF bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7-1 CCP10IF:CCP4IF: CCP<10:4> Interrupt Flag bits(1) Capture Mode 1 = A TMR register capture occurred (must be cleared in software) 0 = No TMR register capture occurred Compare Mode 1 = A TMR register compare match occurred (must be cleared in software) 0 = No TMR register compare match occurred PWM Mode Not used in PWM mode. bit 0 CCP3IF: ECCP3 Interrupt Flag bits Capture Mode 1 = A TMR register capture occurred (must be cleared in software) 0 = No TMR register capture occurred Compare Mode 1 = A TMR register compare match occurred (must be cleared in software) 0 = No TMR register compare match occurred PWM Mode Not used in PWM mode. Note 1: Unimplemented on devices with a program memory of 32 Kbytes (PIC18FX5K90). 2010 Microchip Technology Inc. Preliminary DS39957B-page 135 PIC18F87K90 FAMILY REGISTER 10-8: R/W-0 PIR5: PERIPHERAL INTERRUPT FLAG REGISTER 5 R/W-0 TMR7GIF (1) TMR12IF R/W-0 (1) TMR10IF R/W-0 (1) TMR8IF R/W-0 TMR7IF (1) R/W-0 R/W-0 R/W-0 TMR6IF TMR5IF TMR4IF bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7 TMR7GIF: TMR7 Gate Interrupt Flag bits(1) 1 = TMR gate interrupt occurred (must be cleared in software) 0 = No TMR gate interrupt occurred bit 6 TMR12IF: TMR12 to PR12 Match Interrupt Flag bit(1) 1 = TMR12 to PR12 match occurred (must be cleared in software) 0 = No TMR12 to PR12 match occurred bit 5 TMR10IF: TMR10 to PR10 Match Interrupt Flag bit(1) 1 = TMR10 to PR10 match occurred (must be cleared in software) 0 = No TMR10 to PR10 match occurred bit 4 TMR8IF: TMR8 to PR8 Match Interrupt Flag bit 1 = TMR8 to PR8 match occurred (must be cleared in software) 0 = No TMR8 to PR8 match occurred bit 3 TMR7IF: TMR7 Overflow Interrupt Flag bit(1) 1 = TMR7 register overflowed (must be cleared in software) 0 = TMR7 register did not overflow bit 2 TMR6IF: TMR6 to PR6 Match Interrupt Flag bit 1 = TMR6 to PR6 match occurred (must be cleared in software) 0 = No TMR6 to PR6 match occurred bit 1 TMR5IF: TMR5 Overflow Interrupt Flag bit 1 = TMR5 register overflowed (must be cleared in software) 0 = TMR5 register did not overflow bit 0 TMR4IF: TMR4 to PR4 Match Interrupt Flag bit 1 = TMR4 to PR4 match occurred (must be cleared in software) 0 = No TMR4 to PR4 match occurred Note 1: x = Bit is unknown Unimplemented on devices with a program memory of 32 Kbytes (PIC18FX5K90). DS39957B-page 136 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY REGISTER 10-9: PIR6: PERIPHERAL INTERRUPT FLAG REGISTER 6 U-0 U-0 U-0 R/W-0 U-0 R/W-0 R/W-0 R/W-0 — — — EEIF — CMP3IF CMP2IF CMP1IF bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7-5 Unimplemented: Read as ‘0’ bit 4 EEIF: Data EEDATA/Flash Write Operation Interrupt Flag bit 1 = The write operation is complete (must be cleared in software) 0 = The write operation is not complete, or has not been started bit 3 Unimplemented: Read as ‘0’ bit 2 CMP3IF: CMP3 Interrupt Flag bit 1 = CMP3 interrupt occurred (must be cleared in software) 0 = No CMP3 interrupt occurred bit 1 CMP2IF: CMP2 Interrupt Flag bit 1 = CMP2 interrupt occurred (must be cleared in software) 0 = No CMP2 interrupt occurred bit 0 CMP1IF: CM1 Interrupt Flag bit 1 = CMP1 interrupt occurred (must be cleared in software) 0 = No CMP1 interrupt occurred 2010 Microchip Technology Inc. Preliminary x = Bit is unknown DS39957B-page 137 PIC18F87K90 FAMILY 10.3 PIE Registers The PIE registers contain the individual enable bits for the peripheral interrupts. Due to the number of peripheral interrupt sources, there are six Peripheral Interrupt Enable registers (PIE1 through PIE6). When IPEN (RCON<7>) = 0, the PEIE bit must be set to enable any of these peripheral interrupts. REGISTER 10-10: PIE1: PERIPHERAL INTERRUPT ENABLE REGISTER 1 U-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 — ADIE RC1IE TX1IE SSP1IE TMR1GIE TMR2IE TMR1IE bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7 Unimplemented: Read as ‘0’ bit 6 ADIE: A/D Converter Interrupt Enable bit 1 = Enables the A/D interrupt 0 = Disables the A/D interrupt bit 5 RC1IE: EUSART Receive Interrupt Enable bit 1 = Enables the EUSART receive interrupt 0 = Disables the EUSART receive interrupt bit 4 TX1IE: EUSART Transmit Interrupt Enable bit 1 = Enables the EUSART transmit interrupt 0 = Disables the EUSART transmit interrupt bit 3 SSP1IE: Master Synchronous Serial Port Interrupt Enable bit 1 = Enables the MSSP interrupt 0 = Disables the MSSP interrupt bit 2 TMR1GIE: TMR1 Gate Interrupt Enable bit 1 = Enables the gate 0 = Disables the gate bit 1 TMR2IE: TMR2 to PR2 Match Interrupt Enable bit 1 = Enables the TMR2 to PR2 match interrupt 0 = Disables the TMR2 to PR2 match interrupt bit 0 TMR1IE: TMR1 Overflow Interrupt Enable bit 1 = Enables the TMR1 overflow interrupt 0 = Disables the TMR1 overflow interrupt DS39957B-page 138 Preliminary x = Bit is unknown 2010 Microchip Technology Inc. PIC18F87K90 FAMILY REGISTER 10-11: PIE2: PERIPHERAL INTERRUPT ENABLE REGISTER 2 R/W-0 U-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 OSCFIE — SSP2IE BCL2IE BCL1IE HLVDIE TMR3IE TMR3GIE bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7 OSCFIE: Oscillator Fail Interrupt Enable bit 1 = Enabled 0 = Disabled bit 6 Unimplemented: Read as ‘0’ bit 5 SSP2IE: Master Synchronous Serial Port 2 Interrupt Enable bit 1 = Enables the MSSP interrupt 0 = Disables the MSSP interrupt bit 4 BCL2IE: Bus Collision Interrupt Enable bit 1 = Enables the bus collision interrupt 0 = Disables the bus collision interrupt bit 3 BCL1IE: Bus Collision Interrupt Enable bit 1 = Enabled 0 = Disabled bit 2 HLVDIE: High/Low-Voltage Detect Interrupt Enable bit 1 = Enabled 0 = Disabled bit 1 TMR3IE: TMR3 Overflow Interrupt Enable bit 1 = Enabled 0 = Disabled bit 0 TMR3GIE: Timer3 Gate Interrupt Enable bit 1 = Enabled 0 = Disabled 2010 Microchip Technology Inc. Preliminary x = Bit is unknown DS39957B-page 139 PIC18F87K90 FAMILY REGISTER 10-12: PIE3: PERIPHERAL INTERRUPT ENABLE REGISTER 3 R/W-0 R/W-0 R-0 R-0 R/W-0 R/W-0 R/W-0 R/W-0 TMR5GIE LCDIE RC2IE TX2IE CTMUIE CCP2IE CCP1IE RTCCIE bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7 TMR5GIE: Timer5 Gate Interrupt Enable bit 1 = Enabled 0 = Disabled bit 6 LCDIE: LCD Interrupt Enable bit(1) 1 = Enabled 0 = Disabled bit 5 RC2IE: AUSART Receive Interrupt Enable bit 1 = Enabled 0 = Disabled bit 4 TX2IE: AUSART Transmit Interrupt Enable bit 1 = Enabled 0 = Disabled bit 3 CTMUIE: CTMU Interrupt Enable bit 1 = Enabled 0 = Disabled bit 2 CCP2IE: ECCP2 Interrupt Enable bit 1 = Enabled 0 = Disabled bit 1 CCP1IE: ECCP1 Interrupt Enable bit 1 = Enabled 0 = Disabled bit 0 RTCCIE: RTCC Interrupt Enable bit 1 = Enabled 0 = Disabled Note 1: x = Bit is unknown This bit is valid when the Type-B waveform with Non-Static mode is selected. REGISTER 10-13: PIE4: PERIPHERAL INTERRUPT ENABLE REGISTER 4 R/W-0 (1) CCP10IE R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 CCP9IE(1) CCP8IE CCP7IE CCP6IE CCP5IE CCP4IE CCP3IE bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7-0 Note 1: x = Bit is unknown CCP10IE:CCP3IE: CCP<10:3> Interrupt Enable bits(1) 1 = Enabled 0 = Disabled CCP10IE and CCP9IE are unimplemented on devices with a program memory of 32 Kbytes (PIC18FX5K90). DS39957B-page 140 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY REGISTER 10-14: PIE5: PERIPHERAL INTERRUPT ENABLE REGISTER 5 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 TMR7GIE(1) TMR12IE(1) TMR10IE(1) TMR8IE TMR7IE(1) TMR6IE TMR5IE TMR4IE bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7 TMR7GIE: TMR7 Gate Interrupt Enable bit(1) 1 = Enabled 0 = Disabled bit 6 TMR12IE: TMR12 to PR12 Match Interrupt Enable bit(1) 1 = Enables the TMR12 to PR12 match interrupt 0 = Disables the TMR12 to PR12 match interrupt bit 5 TMR10IE: TMR10 to PR10 Match Interrupt Enable bit(1) 1 = Enables the TMR10 to PR10 match interrupt 0 = Disables the TMR10 to PR10 match interrupt bit 4 TMR8IE: TMR8 to PR8 Match Interrupt Enable bit 1 = Enables the TMR8 to PR8 match interrupt 0 = Disables the TMR8 to PR8 match interrupt bit 3 TMR7IE: TMR7 Overflow Interrupt Enable bit(1) 1 = Enables the TMR7 overflow interrupt 0 = Disables the TMR7 overflow interrupt bit 2 TMR6IE: TMR6 to PR6 Match Interrupt Enable bit 1 = Enables the TMR6 to PR6 match interrupt 0 = Disables the TMR6 to PR6 match interrupt bit 1 TMR5IE: TMR5 Overflow Interrupt Enable bit 1 = Enables the TMR5 overflow interrupt 0 = Disables the TMR5 overflow interrupt bit 0 TMR4IE: TMR4 to PR4 Match Interrupt Enable bit 1 = Enables the TMR4 to PR4 match interrupt 0 = Disables the TMR4 to PR4 match interrupt Note 1: x = Bit is unknown Unimplemented on devices with a program memory of 32 Kbytes (PIC18FX5K90). 2010 Microchip Technology Inc. Preliminary DS39957B-page 141 PIC18F87K90 FAMILY REGISTER 10-15: PIE6: PERIPHERAL INTERRUPT ENABLE REGISTER 6 U-0 U-0 U-0 R/W-0 U-0 R/W-0 R/W-0 R/W-0 — — — EEIE — CMP3IE CMP2IE CMP1IE bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7-5 Unimplemented: Read as ‘0’ bit 4 EEIE: Data EEDATA/Flash Write Operation Enable bit 1 = Interrupt is enabled 0 = interrupt is disabled bit 3 Unimplemented: Read as ‘0’ bit 2 CMP3IE: CMP3 Enable bit 1 = Interrupt is enabled 0 = interrupt is disabled bit 1 CMP2E: CMP2 Enable bit 1 = Interrupt is enabled 0 = interrupt is disabled bit 0 CMP1IE: CMP1 Enable bit 1 = Interrupt is enabled 0 = interrupt is disabled DS39957B-page 142 Preliminary x = Bit is unknown 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 10.4 IPR Registers The IPR registers contain the individual priority bits for the peripheral interrupts. Due to the number of peripheral interrupt sources, there are six Peripheral Interrupt Priority registers (IPR1 through IPR6). Using the priority bits requires that the Interrupt Priority Enable (IPEN) bit (RCON<7>) be set. REGISTER 10-16: IPR1: PERIPHERAL INTERRUPT PRIORITY REGISTER 1 U-0 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 — ADIP RC1IP TX1IP SSP1IP TMR1GIP TMR2IP TMR1IP bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7 Unimplemented: Read as ‘0’ bit 6 ADIP: A/D Converter Interrupt Priority bit 1 = High priority 0 = Low priority bit 5 RC1IP: EUSART Receive Interrupt Priority bit 1 = High priority 0 = Low priority bit 4 TX1IP: EUSART Transmit Interrupt Priority bit x = Bit is unknown 1 = High priority 0 = Low priority bit 3 SSP1IP: Master Synchronous Serial Port Interrupt Priority bit 1 = High priority 0 = Low priority bit 2 TMR1GIP: Timer1 Gate Interrupt Priority bit 1 = High priority 0 = Low priority bit 1 TMR2IP: TMR2 to PR2 Match Interrupt Priority bit 1 = High priority 0 = Low priority bit 0 TMR1IP: TMR1 Overflow Interrupt Priority bit 1 = High priority 0 = Low priority 2010 Microchip Technology Inc. Preliminary DS39957B-page 143 PIC18F87K90 FAMILY REGISTER 10-17: IPR2: PERIPHERAL INTERRUPT PRIORITY REGISTER 2 R/W-1 U-0 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 OSCFIP — SSP2IP BCL2IP BCL1IP HLVDIP TMR3IP TMR3GIP bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7 OSCFIP: Oscillator Fail Interrupt Priority bit 1 = High priority 0 = Low priority bit 6 Unimplemented: Read as ‘0’ bit 5 SSP2IP: Master Synchronous Serial Port 2 Interrupt Priority bit 1 = High priority 0 = Low priority bit 4 BCL2IP: Bus Collision Interrupt priority bit (MSSP) 1 = High priority 0 = Low priority bit 3 BCL1IP: Bus Collision Interrupt Priority bit 1 = High priority 0 = Low priority bit 2 HLVDIP: High/Low-Voltage Detect Interrupt Priority bit 1 = High priority 0 = Low priority bit 1 TMR3IP: TMR3 Overflow Interrupt Priority bit 1 = High priority 0 = Low priority bit 0 TMR3GIP: TMR3 Gate Interrupt Priority bit 1 = High priority 0 = Low priority DS39957B-page 144 Preliminary x = Bit is unknown 2010 Microchip Technology Inc. PIC18F87K90 FAMILY REGISTER 10-18: IPR3: PERIPHERAL INTERRUPT PRIORITY REGISTER 3 R/W-1 R/W-1 R-1 R-1 R/W-1 R/W-1 R/W-1 R/W-1 TMR5GIP LCDIP RC2IP TX2IP CTMUIP CCP2IP CCP1IP RTCCIP bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 TMR5GIP: Timer5 Gate interrupt Priority bit 1 = High priority 0 = Low priority bit 6 LCDIP: LCD Interrupt Priority bit (valid when the Type-B waveform with Non-Static mode is selected) 1 = High priority 0 = Low priority bit 5 RC2IP: AUSART Receive Priority Flag bit 1 = High priority 0 = Low priority bit 4 TX2IP: AUSART Transmit Interrupt Priority bit 1 = High priority 0 = Low priority bit 3 CTMUIP: CTMU Interrupt Priority bit 1 = High priority 0 = Low priority bit CCP2IP: ECCP2 Interrupt Priority bit 1 = High priority 0 = Low priority bit CCP1IP: ECCP1 Interrupt Priority bit 1 = High priority 0 = Low priority bit 0 RTCCIP: RTCC Interrupt Priority bit 1 = High priority 0 = Low priority REGISTER 10-19: IPR4: PERIPHERAL INTERRUPT PRIORITY REGISTER 4 R/W-1 (1) CCP10IP R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 CCP9IP(1) CCP8IP CCP7IP CCP6IP CCP5IP CCP4IP CCP3IP bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7-0 Note 1: x = Bit is unknown CCP10IP:CCP3IP: CCP<10:3> Interrupt Priority bit(1) 1 = High priority 0 = Low priority CCP10IP and CCP9IP are unimplemented on devices with a program memory of 32 Kbytes (PIC18FX5K90). 2010 Microchip Technology Inc. Preliminary DS39957B-page 145 PIC18F87K90 FAMILY REGISTER 10-20: IPR5: PERIPHERAL INTERRUPT PRIORITY REGISTER 5 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 TMR7GIP(1) TMR12IP(1) TMR10IP(1) TMR8IP TMR7IP(1) TMR6IP TMR5IP TMR4IP bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7 TMR7GIP: TMR7 Gate Interrupt Priority bit(1) 1 = High priority 0 = Low priority bit 6 TMR12IP: TMR12 to PR12 Match Interrupt Priority bit(1) 1 = High priority 0 = Low priority bit 5 TMR10IP: TMR10 to PR10 Match Interrupt Priority bit(1) 1 = High priority 0 = Low priority bit 4 TMR8IP: TMR8 to PR8 Match Interrupt Priority bit 1 = High priority 0 = Low priority bit 3 TMR7IP: TMR7 Overflow Interrupt Priority bit(1) 1 = High priority 0 = Low priority bit 2 TMR6IP: TMR6 to PR6 Match Interrupt Priority bit 1 = High priority 0 = Low priority bit 1 TMR5IP: TMR5 Overflow Interrupt Priority bit 1 = High priority 0 = Low priority bit 0 TMR4IP: TMR4 to PR4 Match Interrupt Priority bit 1 = High priority 0 = Low priority Note 1: x = Bit is unknown Unimplemented on devices with a program memory of 32 Kbytes (PIC18FX5K90). DS39957B-page 146 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY REGISTER 10-21: IPR6: PERIPHERAL INTERRUPT PRIORITY REGISTER 6 U-0 U-0 U-0 R/W-1 U-0 R/W-1 R/W-1 R/W-1 — — — EEIE — CMP3IE CMP2IE CMP1IE bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7-5 Unimplemented: Read as ‘0’ bit 4 EEIP: EE Interrupt Priority bit 1 = High priority 0 = Low priority bit 3 SBOREN: Read as ‘0’ bit 2 CMP3IP: CMP3 Interrupt Priority bit 1 = High priority 0 = Low priority bit 1 CMP2IP: CMP2 Interrupt Priority bit 1 = High priority 0 = Low priority bit 0 CMP1IP: CMP1 Interrupt Priority bit 1 = High priority 0 = Low priority 2010 Microchip Technology Inc. Preliminary x = Bit is unknown DS39957B-page 147 PIC18F87K90 FAMILY 10.5 RCON Register The RCON register contains bits used to determine the cause of the last Reset or wake-up from Idle or Sleep modes. RCON also contains the bit that enables interrupt priorities (IPEN). REGISTER 10-22: RCON: RESET CONTROL REGISTER R/W-0 R/W-1 R/W-1 R/W-1 R-1 R-1 R/W-0 R/W-0 IPEN SBOREN CM RI TO PD POR BOR bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 IPEN: Interrupt Priority Enable bit 1 = Enable priority levels on interrupts 0 = Disable priority levels on interrupts (PIC16CXXX Compatibility mode) bit 6 SBOREN: BOR Software Enable bit If BOREN<1:0> = 01: 1 = BOR is enabled 0 = BOR is disabled If BOREN<1:0> = 00, 10 or 11: Bit is disabled and read as ‘0’. bit 5 CM: Configuration Mismatch Flag bit 1 = A Configuration Mismatch Reset has not occurred 0 = A Configuration Mismatch Reset has occurred (must be subsequently set in software) bit 4 RI: RESET Instruction Flag bit For details of bit operation, see Register 5-1. bit 3 TO: Watchdog Timer Time-out Flag bit For details of bit operation, see Register 5-1. bit 2 PD: Power-Down Detection Flag bit For details of bit operation, see Register 5-1. bit 1 POR: Power-on Reset Status bit For details of bit operation, see Register 5-1. bit 0 BOR: Brown-out Reset Status bit For details of bit operation, see Register 5-1. DS39957B-page 148 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 10.6 INTx Pin Interrupts External interrupts on the RB0/INT0, RB1/INT1, RB2/INT2 and RB3/INT3 pins are edge-triggered. If the corresponding INTEDGx bit in the INTCON2 register is set (= 1), the interrupt is triggered by a rising edge. If that bit is clear, the trigger is on the falling edge. When a valid edge appears on the RBx/INTx pin, the corresponding flag bit, INTxIF, is set. This interrupt can be disabled by clearing the corresponding enable bit, INTxIE. Before re-enabling the interrupt, the flag bit (INTxIF) must be cleared in software in the Interrupt Service Routine. All external interrupts (INT0, INT1, INT2 and INT3) can wake up the processor from the power-managed modes, if bit, INTxIE, was set prior to going into the power-managed modes. If the Global Interrupt Enable bit (GIE) is set, the processor will branch to the interrupt vector following wake-up. The interrupt priority for INT1, INT2 and INT3 is determined by the value contained in the Interrupt Priority bits, INT1IP (INTCON3<6>), INT2IP (INTCON3<7>) and INT3IP (INTCON2<1>). There is no priority bit associated with INT0. It is always a high-priority interrupt source. 10.7 TMR0 Interrupt In 8-bit mode (the default), an overflow in the TMR0 register (FFh 00h) will set flag bit, TMR0IF. In 16-bit mode, an overflow in the TMR0H:TMR0L register pair (FFFFh 0000h) will set TMR0IF. EXAMPLE 10-1: MOVWF MOVFF MOVFF ; ; USER ; MOVFF MOVF MOVFF The interrupt can be enabled/disabled by setting/clearing enable bit, TMR0IE (INTCON<5>). Interrupt priority for Timer0 is determined by the value contained in the interrupt priority bit, TMR0IP (INTCON2<2>). For further details on the Timer0 module, see Section 12.0 “Timer0 Module”. 10.8 PORTB Interrupt-on-Change An input change on PORTB<7:4> sets flag bit, RBIF (INTCON<0>). The interrupt can be enabled/disabled by setting/clearing enable bit, RBIE (INTCON<3>). Interrupt priority for PORTB interrupt-on-change is determined by the value contained in the interrupt priority bit, RBIP (INTCON2<0>). 10.9 Context Saving During Interrupts During interrupts, the return PC address is saved on the stack. Additionally, the WREG, STATUS and BSR registers are saved on the Fast Return Stack. If a fast return from interrupt is not used (see Section 6.3 “Data Memory Organization”), the user may need to save the WREG, STATUS and BSR registers on entry to the Interrupt Service Routine (ISR). Depending on the user’s application, other registers also may need to be saved. Example 10-1 saves and restores the WREG, STATUS and BSR registers during an Interrupt Service Routine. SAVING STATUS, WREG AND BSR REGISTERS IN RAM W_TEMP STATUS, STATUS_TEMP BSR, BSR_TEMP ; W_TEMP is in virtual bank ; STATUS_TEMP located anywhere ; BSR_TMEP located anywhere ISR CODE BSR_TEMP, BSR W_TEMP, W STATUS_TEMP, STATUS 2010 Microchip Technology Inc. ; Restore BSR ; Restore WREG ; Restore STATUS Preliminary DS39957B-page 149 PIC18F87K90 FAMILY TABLE 10-1: Name SUMMARY OF REGISTERS ASSOCIATED WITH INTERRUPTS Bit 4 Bit 3 INT0IE RBIE Bit 2 INTCON GIE/GIEH PEIE/GIEL TMR0IE INTCON2 RBPU INTEDG0 INTEDG1 INTCON3 INT2IP INT1IP INT3IE INT2IE INT1IE INT3IF INT2IF INT1IF 73 — ADIF RC1IF TX1IF SSP1IF TMR1GIF TMR2IF TMR1IF 75 INTEDG2 INTEDG3 Bit 1 Reset Values on Page: Bit 6 PIR1 Bit 5 Bit 0 Bit 7 TMR0IF INT0IF RBIF 73 TMR0IP INT3IP RBIP 73 PIR2 OSCFIF — SSP2IF BCL2IF BCL1IF HLVDIF TMR3IF TMR3GIF 75 PIR3 TMR5GIF LCDIF RC2IF TX2IF CTMUIF CCP2IF CCP1IF RTCCIF 75 PIR4 CCP10IF(1) CCP9IF(1) CCP7IF CCP6IF CCP5IF CCP4IF CCP3IF 75 PIR5 (1) CCP8IF TMR10IF (1) TMR8IF TMR7IF (1) TMR6IF TMR5IF TMR4IF 75 PIR6 — — — EEIF — CMP3IF CMP2IF CMP1IF 75 PIE1 — ADIE RC1IE TX1IE SSP1IE TMR1GIE TMR2IE TMR1IE 75 TMR7GIF TMR12IF (1) PIE2 OSCFIE — SSP2IE BCL2IE BCL1IE HLVDIE TMR3IE TMR3GIE 75 PIE3 TMR5GIE LCDIE RC2IE TX2IE CTMUIE CCP2IE CCP1IE RTCCIE 75 CCP9IE(1) CCP8IE 75 (1) PIE4 CCP10IE PIE5 TMR7GIE(1) TMR12IE(1) TMR10IE(1) CCP6IE CCP5IE CCP4IE CCP3IE TMR7IE(1) TMR6IE TMR5IE TMR4IE 75 EEIE — CMP3IE CMP2IE CMP1IE 78 — — IPR1 — ADIP RC1IP TX1IP SSP1IP TMR1GIP TMR2IP TMR1IP 75 IPR2 OSCFIP — SSP2IP BCL2IP BCL1IP HLVDIP TMR3IP TMR3GIP 75 IPR3 TMR5GIP LCDIP RC2IP TX2IP CTMUIP CCP2IP CCP1IP RTCCIP 75 CCP9IP(1) CCP8IP PIE6 (1) — CCP7IE TMR8IE IPR4 CCP10IP IPR5 TMR7GIP(1) TMR12IP(1) TMR10IP(1) IPR6 RCON Legend: Note 1: CCP7IP CCP6IP CCP5IP CCP4IP CCP3IP 75 TMR8IP TMR7IP(1) TMR6IP TMR5IP TMR4IP 74 — — — EEIE — CMP3IE CMP2IE CMP1IE 75 IPEN SBOREN CM RI TO PD POR BOR 74 Shaded cells are not used by the interrupts. Unimplemented on devices with a program memory of 32 Kbytes (PIC18FX5K90). DS39957B-page 150 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 11.0 I/O PORTS 11.1 Depending on the device selected and features enabled, there are up to nine ports available. Some pins of the I/O ports are multiplexed with an alternate function from the peripheral features on the device. In general, when a peripheral is enabled, that pin may not be used as a general purpose I/O pin. Each port has three memory mapped registers for its operation: • TRIS register (Data Direction register) • PORT register (reads the levels on the pins of the device) • LAT register (Output Latch register) Reading the PORT register reads the current status of the pins, whereas writing to the PORT register writes to the Output Latch (LAT) register. Setting a TRIS bit (= 1) makes the corresponding port pin an input (putting the corresponding output driver in a High-Impedance mode). Clearing a TRIS bit (= 0) makes the corresponding port pin an output (i.e., put the contents of the corresponding LAT bit on the selected pin). The Output Latch (LAT register) is useful for read-modify-write operations on the value that the I/O pins are driving. Read-modify-write operations on the LAT register read and write the latched output value for the PORT register. A simplified model of a generic I/O port, without the interfaces to other peripherals, is shown in Figure 11-1. FIGURE 11-1: GENERIC I/O PORT OPERATION When developing an application, the capabilities of the port pins must be considered. Outputs on some pins have higher output drive strength than others. Similarly, some pins can tolerate higher than VDD input levels. All of the digital ports are 5.5V input tolerant. The analog ports have the same tolerance, having clamping diodes implemented internally. 11.1.1 Data Bus WR LAT or PORT D Q I/O Pin CKx Data Latch D WR TRIS Q CKx TRIS Latch Input Buffer PIN OUTPUT DRIVE When used as digital I/O, the output pin drive strengths vary, according to the pins’ grouping to meet the needs for a variety of applications. In general, there are two classes of output pins, in terms of drive capability: • Outputs designed to drive higher current loads such as LEDs: - PORTA - PORTB - PORTC • Outputs with lower drive levels, but capable of driving normal digital circuit loads with a high input impedance. Able to drive LEDs, but only those with smaller current requirements: - PORTD - PORTE - PORTF - PORTG - PORTH(†) - PORTJ(†) † These ports are not available on 64-pin devices. For more details, see “Absolute Maximum Ratings” in Section 31.0 “Electrical Characteristics”. Regardless of its port, all output pins in LCD Segment or Common-mode have sufficient output to directly drive a display. 11.1.2 RD LAT I/O Port Pin Capabilities PULL-UP CONFIGURATION Four of the I/O ports (PORTB, PORTD, PORTE and PORTJ) implement configurable weak pull-ups on all pins. These are internal pull-ups that allow floating digital input signals to be pulled to a consistent level without the use of external resistors. The pull-ups are enabled with a single bit for each of the ports: RBPU (INTCON2<7>) for PORTB, and RDPU, REPU and RJPU (PADCFG1<7:5>) for the other ports. By setting RDPU, REPU and RJPU, each of the pull-ups on these ports can be enabled. The pull-ups are disabled on a POR event. RD TRIS Q D ENEN RD PORT 2010 Microchip Technology Inc. Preliminary DS39957B-page 151 PIC18F87K90 FAMILY 11.1.3 OPEN-DRAIN OUTPUTS FIGURE 11-2: The output pins for several peripherals are also equipped with a configurable, open-drain output option. This allows the peripherals to communicate with external digital logic, operating at a higher voltage level, without the use of level translators. USING THE OPEN-DRAIN OUTPUT (USART SHOWN AS EXAMPLE) 3.3V +5V PIC18F67K90 The open-drain option is implemented on port pins specifically associated with the data and clock outputs of the USARTs, the MSSP module (in SPI mode) and the CCP modules. This option is selectively enabled by setting the open-drain control bits in the registers ODCON1, ODCON2 and ODCON3. VDD TXX (at logic ‘1’) 3.3V 5V When the open-drain option is required, the output pin must also be tied through an external pull-up resistor provided by the user to a higher voltage level, up to 5V (Figure 11-2). When a digital logic high signal is output, it is pulled up to the higher voltage level. REGISTER 11-1: ODCON1: PERIPHERAL OPEN-DRAIN CONTROL REGISTER 1 R/W-0 R/W-0 R/W-0 U-0 U-0 U-0 U-0 R/W-0 SSP1OD CCP2OD CCP1OD — — — — SSP2OD bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7 SSP1OD: SPI1 Open-Drain Output Enable bit 1 = Open-drain capability is enabled 0 = Open-drain capability is disabled bit 6 CCP2OD: ECCP2 Open-Drain Output Enable bit 1 = Open-drain capability is enabled 0 = Open-drain capability is disabled bit 5 CCP1OD: ECCP1 Open-Drain Output Enable bit 1 = Open-drain capability is enabled 0 = Open-drain capability is disabled bit 4-1 Unimplemented: Read as ‘0’ bit 0 SSP2OD: SPI2 Open-Drain Output Enable bit 1 = Open-drain capability is enabled 0 = Open-drain capability is disabled DS39957B-page 152 Preliminary x = Bit is unknown 2010 Microchip Technology Inc. PIC18F87K90 FAMILY REGISTER 11-2: R/W-0 (1) CCP10OD ODCON2: PERIPHERAL OPEN-DRAIN CONTROL REGISTER 2 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 CCP9OD(1) CCP8OD CCP7OD CCP6OD CCP5OD CCP4OD CCP3OD bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7 CCP10OD: CCP10 Open-Drain Output Enable bit(1) 1 = Open-drain capability is enabled 0 = Open-drain capability is disabled bit 6 CCP9OD: CCP9 Open-Drain Output Enable bit(1) 1 = Open-drain capability is enabled 0 = Open-drain capability is disabled bit 5 CCP8OD: CCP8 Open-Drain Output Enable bit 1 = Open-drain capability is enabled 0 = Open-drain capability is disabled bit 4 CCP7OD: CCP7 Open-Drain Output Enable bit 1 = Open-drain capability is enabled 0 = Open-drain capability is disabled bit 3 CCP6OD: CCP6 Open-Drain Output Enable bit 1 = Open-drain capability is enabled 0 = Open-drain capability is disabled bit 2 CCP5OD: CCP5 Open-Drain Output Enable bit 1 = Open-drain capability is enabled 0 = Open-drain capability is disabled bit 1 CCP4OD: CCP4 Open-Drain Output Enable bit 1 = Open-drain capability is enabled 0 = Open-drain capability is disabled bit 0 CCP3OD: ECCP3 Open-Drain Output Enable bit 1 = Open-drain capability is enabled 0 = Open-drain capability is disabled Note 1: x = Bit is unknown Unimplemented on PIC18FX5K90 devices. 2010 Microchip Technology Inc. Preliminary DS39957B-page 153 PIC18F87K90 FAMILY REGISTER 11-3: R/W-0 U2OD ODCON3: PERIPHERAL OPEN-DRAIN CONTROL REGISTER 3 R/W-0 U-0 U-0 U-0 U-0 U-0 R/W-0 U1OD — — — — — CTMUDS bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7 U2OD: EUSART2 Open-Drain Output Enable bit 1 = Open-drain capability is enabled 0 = Open-drain capability is disabled bit 6 U1OD: EUSART1 Open-Drain Output Enable bit 1 = Open-drain capability is enabled 0 = Open-drain capability is disabled bit 5-1 Unimplemented: Read as ‘0’ bit 0 CTMUDS: CTMU Pulse Delay Enable bit 1 = Pulse delay input for CTMU is enabled on pin, RF1 0 = Pulse delay input for CTMU is disabled on pin, RF1 11.1.4 ANALOG AND DIGITAL PORTS Many of the ports multiplex analog and digital functionality, providing a lot of flexibility for hardware designers. PIC18F87K90 family devices can make any analog pin analog or digital, depending on an application’s needs. The ports’ analog/digital functionality is controlled by the registers: ANCON0, ANCON1 and ANCON2. DS39957B-page 154 x = Bit is unknown Setting these registers makes the corresponding pins analog and clearing the registers makes the ports digital. For details on these registers, see Section 23.0 “12-Bit Analog-to-Digital Converter (A/D) Module”. Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 11.2 PORTA, TRISA and LATA Registers PORTA is an 8-bit wide, bidirectional port. The corresponding Data Direction and Output Latch registers are TRISA and LATA. RA4/T0CKI is a Schmitt Trigger input. All other PORTA pins have TTL input levels and full CMOS output drivers. The RA4 pin is multiplexed with the Timer0 clock input and one of the LCD segment drives. RA5 and RA<3:0> are multiplexed with analog inputs for the A/D Converter. RA1 is multiplexed with analog as well as the LCD segment drive. The operation of the analog inputs as A/D Converter inputs is selected by clearing or setting the ANSEL<3:0> control bits in the ANCON1 register. The corresponding TRISA bits control the direction of these pins, even when they are being used as analog inputs. The user must ensure the bits in the TRISA register are maintained set when using them as analog inputs. Note: RA5 and RA<3:0> are configured as analog inputs on any Reset and are read as ‘0’. RA4 is configured as a digital input. OSC2/CLKO/RA6 and OSC1/CLKI/RA7 normally serve as the external circuit connections for the external (primary) oscillator circuit (HS Oscillator modes) or the external clock input and output (EC Oscillator modes). In these cases, RA6 and RA7 are not available as digital I/O and their corresponding TRIS and LAT bits are read as ‘0’. When the device is configured to use HF-INTOSC, MF-INTOSC or LF-INTOSC as the default oscillator mode, RA6 and RA7 are automatically configured as digital I/O; the oscillator and clock in/clock out functions are disabled. RA1, RA4 and RA5 are multiplexed with LCD segment drives that are controlled by bits in the LCDSE1 and LCDSE2 registers. I/O port functionality is only available when the LCD segments are disabled. RA5 has additional functionality for Timer1 and Timer3. It can be configured as the Timer1 clock input or the Timer3 external clock gate input. EXAMPLE 11-1: PORTA CLRF LATA BANKSEL MOVLW MOVWF MOVLW ANCON1 00h ; Configure A/D ANCON1 ; for digital inputs 0BFh ; Value used to initialize ; data direction TRISA ; Set RA<7, 5:0> as inputs, ; RA<6> as output MOVWF 2010 Microchip Technology Inc. INITIALIZING PORTA CLRF Preliminary ; ; ; ; Initialize PORTA by clearing output latches Alternate method to clear output data latches DS39957B-page 155 PIC18F87K90 FAMILY TABLE 11-1: PORTA FUNCTIONS Pin Name Function TRIS Setting I/O I/O Type RA0/AN0/ULPWU RA0 0 O DIG 1 I TTL PORTA<0> data input; disabled when analog input enabled. AN0 1 I ANA A/D Input Channel 0. Default input configuration on POR; does not affect digital output. ULPWU 1 I ANA Ultra low-power wake-up input. RA1 0 O DIG LATA<1> data output; not affected by analog input. 1 I TTL PORTA<1> data input; disabled when analog input is enabled. 1 I ANA A/D Input Channel 1. Default input configuration on POR; does not affect digital output. RA1/AN1/SEG18 AN1 RA2/AN2/VREF- RA4/T0CKI/ SEG14 RA5/AN4/SEG15/ T1CKI/T3G/ HLVDIN OSC2/CLKO/RA6 OSC1/CLKI/RA7 Legend: LATA<0> data output; not affected by analog input. SEG18 1 O ANA LCD Segment 18 output; disables all other pin functions. RA2 0 O DIG LATA<2> data output; not affected by analog input. 1 I TTL PORTA<2> data input; disabled when analog functions are enabled. 1 I ANA A/D Input Channel 2. Default input configuration on POR. AN2 RA3/AN3/VREF+ Description VREF- 1 I ANA A/D and comparator low reference voltage input. RA3 0 O DIG LATA<3> data output; not affected by analog input. 1 I TTL PORTA<3> data input; disabled when analog input is enabled. AN3 1 I ANA A/D Input Channel 3. Default input configuration on POR. VREF+ 1 I ANA A/D and comparator high reference voltage input. RA4 0 O DIG LATA<4> data output. PORTA<4> data input. Default configuration on POR. 1 I ST T0CKI x I ST SEG14 1 O ANA LCD Segment 14 output; disables all other pin functions. RA5 0 O DIG LATA<5> data output; not affected by analog input. Timer0 clock input. 1 I TTL PORTA<5> data input; disabled when analog input is enabled. AN4 1 I ANA A/D Input Channel 4. Default configuration on POR. SEG15 1 O ANA LCD Segment 15 output; disables all other pin functions. T1CKI x I ST Timer1 clock input. T3G x I ST HLVDIN 1 I ANA High/Low-Voltage Detect external trip point input. Timer3 external clock gate input. OSC2 x O ANA Main oscillator feedback output connection (HS, XT and LP modes). CLKO x O DIG System cycle clock output (FOSC/4, EC and INTOSC modes). RA6 0 O DIG LATA<6> data output; disabled when OSC2 Configuration bit is set. 1 I TTL PORTA<6> data input; disabled when OSC2 Configuration bit is set. OSC1 x I ANA Main oscillator input connection (HS, XT and LP modes). CLKI x I ANA Main external clock source input (EC modes). RA7 0 O DIG LATA<7> data output; disabled when OSC2 Configuration bit is set. 1 I TTL PORTA<7> data input; disabled when OSC2 Configuration bit is set. O = Output, I = Input, ANA = Analog Signal, DIG = Digital Output, ST = Schmitt Trigger Buffer Input, TTL = TTL Buffer Input, x = Don’t care (TRIS bit does not affect port direction or is overridden for this option). DS39957B-page 156 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY TABLE 11-2: SUMMARY OF REGISTERS ASSOCIATED WITH PORTA Bit 0 Reset Values on Page: RA1 RA0 76 LATA1 LATA0 76 TRISA1 TRISA0 76 ANCON1 ANSEL15 ANSEL14 ANSEL13 ANSEL12 ANSEL11 ANSEL10 Name PORTA Bit 7 Bit 6 RA7(1) RA6(1) RA5 RA4 RA3 RA2 LATA6(1) LATA5 LATA4 LATA3 LATA2 TRISA5 TRISA4 TRISA3 TRISA2 (1) LATA LATA7 TRISA TRISA7(1) Bit 5 (1) TRISA6 Bit 4 Bit 3 Bit 2 Bit 1 ANSEL9 ANSEL8 79 LCDSE1 SE15 SE14 SE13 SE12 SE11 SE10 SE09 SE08 81 LCDSE2 SE23 SE22 SE21 SE20 SE19 SE18 SE17 SE16 81 Legend: — = unimplemented, read as ‘0’. Shaded cells are not used by PORTA. Note 1: These bits are enabled depending on the oscillator mode selected. When not enabled as PORTA pins, they are disabled and read as ‘x’. 2010 Microchip Technology Inc. Preliminary DS39957B-page 157 PIC18F87K90 FAMILY 11.3 PORTB, TRISB and LATB Registers PORTB is an 8-bit wide, bidirectional port. The corresponding Data Direction and Output Latch registers are TRISB and LATB. All pins on PORTB are digital only. EXAMPLE 11-2: CLRF PORTB CLRF LATB MOVLW 0CFh MOVWF TRISB INITIALIZING PORTB ; ; ; ; ; ; ; ; ; ; ; ; Initialize PORTB by clearing output data latches Alternate method to clear output data latches Value used to initialize data direction Set RB<3:0> as inputs RB<5:4> as outputs RB<7:6> as inputs Four of the PORTB pins (RB<7:4>) have an interrupt-on-change feature. Only pins configured as inputs can cause this interrupt to occur; any RB<7:4> pin configured as an output would be excluded from the interrupt-on-change comparison. Comparisons with the input pins (of RB<7:4>) are made with the old value latched on the last read of PORTB. The “mismatch” outputs of RB<7:4> are ORed together to generate the RB Port Change Interrupt with Flag bit, RBIF (INTCON<0>). This interrupt can wake the device from power-managed modes. To clear the interrupt in the Interrupt Service Routine: a) b) c) Each of the PORTB pins has a weak internal pull-up. A single control bit can turn on all the pull-ups. This is performed by clearing bit, RBPU (INTCON2<7>). The weak pull-up is automatically turned off when the port pin is configured as an output. The pull-ups are disabled on a Power-on Reset. Any read or write of PORTB (except with the MOVFF (ANY), PORTB instruction). This will end the mismatch condition. Wait one instruction cycle (such as executing a NOP instruction). Clear flag bit, RBIF. A mismatch condition will continue to set flag bit, RBIF. Reading PORTB will end the mismatch condition and allow flag bit, RBIF, to be cleared after one TCY delay. The interrupt-on-change feature is recommended for wake-up on key depression operation and operations where PORTB is only used for the interrupt-on-change feature. Polling of PORTB is not recommended while using the interrupt-on-change feature. The RB<3:2> pins are multiplexed as CTMU edge inputs. RB5 has an additional function for Timer3 and Timer1. It can be configured for Timer3 clock input or Timer1 external clock gate input. The RB<5:0> pins also are multiplexed with LCD segment drives that are controlled by bits in the registers, LCDSE1 and LCDSE3. I/O port functionality is only available when the LCD segments are disabled. DS39957B-page 158 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY TABLE 11-3: Pin Name RB0/INT0/SEG30/ FLT0 RB1/INT1/SEG8 RB2/INT2/SEG9/ CTED1 RB3/INT3/SEG10/ CTED2/ECCP2/ P2A RB4/KBI0/SEG11 RB5/KBI1/SEG29/ T3CKI/T1G RB6/KBI2/PGC RB7/KBI3/PGD Legend: PORTB FUNCTIONS Function TRIS Setting I/O I/O Type RB0 0 O DIG 1 I TTL PORTB<0> data input; weak pull-up when RBPU bit is cleared. INT0 1 I ST External Interrupt 0 input. SEG30 1 O ANA Description LATB<0> data output. LCD Segment 30 output; disables all other pin functions. FLT0 x I ST Enhanced PWM Fault input for ECCPx. RB1 0 O DIG LATB<1> data output. 1 I TTL PORTB<1> data input; weak pull-up when RBPU bit is cleared. INT1 1 I ST SEG8 1 O ANA LCD Segment 8 output; disables all other pin functions. External Interrupt 1 input. RB2 0 O DIG LATB<2> data output. 1 I TTL PORTB<2> data input; weak pull-up when RBPU bit is cleared. INT2 1 I ST External Interrupt 2 input. SEG9 1 O ANA CTED1 x I ST LCD Segment 9 output; disables all other pin functions. CTMU Edge 1 input. RB3 0 O DIG LATB<3> data output. 1 I TTL PORTB<3> data input; weak pull-up when RBPU bit is cleared. INT3 1 I ST External Interrupt 3 input. SEG10 1 O ANA CTED2 x I ST LCD Segment 10 output; disables all other pin functions. CTMU Edge 2 input. ECCP2 0 O DIG ECCP2 compare output and ECCP2 PWM output. Takes priority over port data. 1 I ST ECCP2 capture input. P2A 0 O DIG ECCP2 Enhanced PWM output, Channel A. May be configured for tri-state during Enhanced PWM shutdown events. Takes priority over port data. RB4 0 O DIG LATB<4> data output. PORTB<4> data input; weak pull-up when RBPU bit is cleared. 1 I TTL KBI0 1 I TTL Interrupt-on-pin change. SEG11 1 O ANA LCD Segment 11 output; disables all other pin functions. RB5 0 O DIG LATB<5> data output. 1 I TTL PORTB<5> data input; weak pull-up when RBPU bit is cleared. KBI1 1 I TTL Interrupt-on-pin change. SEG29 1 O ANA LCD Segment 29 output; disables all other pin functions. T3CKI x I ST T1G x I ST Timer1 external clock gate input. RB6 0 O DIG LATB<6> data output. PORTB<6> data input; weak pull-up when RBPU bit is cleared. Timer3 clock input. 1 I TTL KBI2 1 I TTL Interrupt-on-pin change. PGC x I ST Serial execution (ICSP) clock input for ICSP and ICD operation. RB7 0 O DIG LATB<7> data output. 1 I TTL PORTB<7> data input; weak pull-up when RBPU bit is cleared. KBI3 1 I TTL Interrupt-on-pin change. PGD x O DIG Serial execution data output for ICSP and ICD operation. x I ST Serial execution data input for ICSP and ICD operation. O = Output, I = Input, ANA = Analog Signal, DIG = Digital Output, ST = Schmitt Trigger Buffer Input, TTL = TTL Buffer Input, x = Don’t care (TRIS bit does not affect port direction or is overridden for this option). 2010 Microchip Technology Inc. Preliminary DS39957B-page 159 PIC18F87K90 FAMILY TABLE 11-4: SUMMARY OF REGISTERS ASSOCIATED WITH PORTB Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Reset Values on Page: PORTB RB7 RB6 RB5 RB4 RB3 RB2 RB1 RB0 76 LATB LATB7 LATB6 LATB5 LATB4 LATB3 LATB2 LATB1 LATB0 76 TRISB TRISB7 TRISB6 TRISB5 TRISB4 TRISB3 TRISB2 TRISB1 TRISB0 76 TMR0IE INT0IE RBIE INTCON GIE/GIEH PEIE/GIEL INTCON2 RBPU INTEDG0 INTCON3 INT2IP INT1IP INT3IE INT2IE LCDSE1 SE15 SE14 SE13 SE12 LCDSE3 SE31 SE30 SE29 SE28 TMR0IF INT0IF RBIF 73 TMR0IP INT3IP RBIP 73 INT1IE INT3IF INT2IF INT1IF 73 SE11 SE10 SE09 SE08 81 SE27 SE26 SE25 SE24 81 INTEDG1 INTEDG2 INTEDG3 Legend: Shaded cells are not used by PORTB. DS39957B-page 160 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 11.4 PORTC, TRISC and LATC Registers PORTC is an 8-bit wide, bidirectional port. The corresponding Data Direction and Output Latch registers are TRISC and LATC. Only PORTC pins, RC2 through RC7, are digital only pins. PORTC is multiplexed with ECCP, MSSP and EUSART peripheral functions (Table 11-5). The pins have Schmitt Trigger input buffers. The pins for ECCP, SPI and EUSART are also configurable for open-drain output whenever these functions are active. Open-drain configuration is selected by setting the SSP1OD, CCPxOD and U1OD control bits in the registers, ODCON1 and ODCON3. RC1 is normally configured as the default peripheral pin for the ECCP2 module. Assignment of ECCP2 is controlled by Configuration bit, CCP2MX (default state, CCP2MX = 1). When enabling peripheral functions, use care in defining TRIS bits for each PORTC pin. Some peripherals can override the TRIS bit to make a pin an output or input. Consult the corresponding peripheral section for the correct TRIS bit settings. Note: The contents of the TRISC register are affected by peripheral overrides. Reading TRISC always returns the current contents, even though a peripheral device may be overriding one or more of the pins. The RC<7:1> pins are multiplexed with LCD segment drives that are controlled by bits in the registers, LCDSE1, LCDSE2, LCDSE3 and LCDSE4. RC0 and RC1 pins serve as the input pins for the SOSC oscillator. On a power-up, these pins are defined as SOSC pins. In order to make these ports have digital I/O port functionality, the CONFI1L<4:3> should be set to ‘10’ (Digital SCLKI mode). I/O port functionality is only available when the LCD segments are disabled. EXAMPLE 11-3: CLRF PORTC CLRF LATC MOVLW 0CFh MOVWF TRISC These pins are configured as digital inputs on any device Reset. 2010 Microchip Technology Inc. Preliminary INITIALIZING PORTC ; ; ; ; ; ; ; ; ; ; ; ; Initialize PORTC by clearing output data latches Alternate method to clear output data latches Value used to initialize data direction Set RC<3:0> as inputs RC<5:4> as outputs RC<7:6> as inputs DS39957B-page 161 PIC18F87K90 FAMILY TABLE 11-5: PORTC FUNCTIONS Pin Name Function TRIS Setting I/O I/O Type RC0/SOSCO/ SCLKI/ RC0 0 O DIG LATC<0> data output. PORTC<0> data input. RC1/SOSCI/ ECCP2/P2A/ SEG32 RC2/ECCP1/ P1A/SEG13 1 I ST SOSCO 1 I ST SCLKI x O ANA Digital clock input; enabled when SOSC oscillator is disabled. RC1 0 O DIG LATC<1> data output. 1 I ST PORTC<1> data input. SOSCI x I ANA SOSC oscillator input. ECCP2(1) 0 O DIG ECCP2 compare output and ECCP2 PWM output. Takes priority over port data. 1 I ST ECCP2 capture input. P2A 0 O DIG ECCP2 Enhanced PWM output, Channel A. May be configured for tri-state during Enhanced PWM shutdown events. Takes priority over port data. SEG32 1 O ANA LCD Segment 32 output; disables all other pin functions. RC2 0 O DIG LATC<2> data output. 1 I ST PORTC<2> data input. 0 O DIG ECCP1 compare output and ECCP1 PWM output. Takes priority over port data. 1 I ST ECCP1 capture input. P1A 0 O DIG ECCP1 Enhanced PWM output, Channel A. May be configured for tri-state during Enhanced PWM shutdown events. Takes priority over port data. SEG13 1 O ANA LCD Segment 13 output; disables all other pin functions. RC3 0 O DIG LATC<3> data output. 1 I ST PORTC<3> data input. 0 O DIG SPI clock output (MSSP module); takes priority over port data. 1 I ST SPI clock input (MSSP module). 0 O DIG I2C™ clock output (MSSP module); takes priority over port data. 1 I I2C I2C clock input (MSSP module); input type depends on module setting. SEG17 1 O ANA LCD Segment 17 output; disables all other pin functions. RC4 0 O DIG LATC<4> data output. 1 I ST PORTC<4> data input. I ST SPI data input (MSSP module). 1 O DIG I2C data output (MSSP module); takes priority over port data. 1 I I2C I2C data input (MSSP module); input type depends on module setting. SEG16 1 O ANA RC5 0 O DIG LATC<5> data output. 1 I ST PORTC<5> data input. SDO1 0 O DIG SPI data output (MSSP module). SEG12 1 O ANA LCD Segment 12 output; disables all other pin functions. RC6 0 O DIG LATC<6> data output. 1 I ST PORTC<6> data input. 1 O DIG Synchronous serial data output (EUSART module); takes priority over port data. ECCP1 RC3/SCK1/ SCL1/SEG17 SCK1 SCL1 RC4/SDI1/ SDA1/SEG16 SDI1 SDA1 RC5/SDO1/ SEG12 RC6/TX1/CK1/ SEG27 TX1 CK1 SEG27 Legend: Note 1: Description SOSC oscillator output. LCD Segment 16 output; disables all other pin functions. 1 O DIG Synchronous serial data input (EUSART module); user must configure as an input. 1 I ST Synchronous serial clock input (EUSART module). 1 O ANA LCD Segment 27 output; disables all other pin functions. O = Output, I = Input, ANA = Analog Signal, DIG = Digital Output, ST = Schmitt Trigger Buffer Input, TTL = TTL Buffer Input, I2C = I2C Buffer Input, x = Don’t care (TRIS bit does not affect port direction or is overridden for this option). Default assignment for ECCP2 when the CCP2MX Configuration bit is set. DS39957B-page 162 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY TABLE 11-5: PORTC FUNCTIONS (CONTINUED) Pin Name Function TRIS Setting I/O I/O Type RC7/RX1/DT1/ SEG28 RC7 0 O DIG LATC<7> data output. PORTC<7> data input. 1 I ST RX1 1 I ST Asynchronous serial receive data input (EUSART module). DT1 1 O DIG Synchronous serial data output (EUSART module); takes priority over port data. 1 I ST Synchronous serial data input (EUSART module); user must configure as an input. 1 O ANA SEG28 Legend: Note 1: PORTC LCD Segment 28 output; disables all other pin functions. O = Output, I = Input, ANA = Analog Signal, DIG = Digital Output, ST = Schmitt Trigger Buffer Input, TTL = TTL Buffer Input, I2C = I2C Buffer Input, x = Don’t care (TRIS bit does not affect port direction or is overridden for this option). Default assignment for ECCP2 when the CCP2MX Configuration bit is set. TABLE 11-6: Name Description SUMMARY OF REGISTERS ASSOCIATED WITH PORTC Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Reset Values on Page: RC7 RC6 RC5 RC4 RC3 RC2 RC1 RC0 76 LATC LATC7 LATBC6 LATC5 LATCB4 LATC3 LATC2 LATC1 LATC0 76 TRISC TRISC7 TRISC6 TRISC5 TRISC4 TRISC3 TRISC2 TRISC1 TRISC0 76 LCDSE1 SE15 SE14 SE13 SE12 SE11 SE10 SE09 SE08 81 LCDSE2 SE23 SE22 SE21 SE20 SE19 SE18 SE17 SE16 81 LCDSE3 SE31 SE30 SE29 SE28 SE27 SE26 SE25 SE24 81 LCDSE4 SE39(1) SE38(1) SE37(1) SE36(1) SE35(1) SE34(1) SE33(1) SE32 81 — — — — SSP2OD 79 ODCON1 SSP1OD CCP2OD CCP1OD Legend: Shaded cells are not used by PORTC. Note 1: Unimplemented on PIC18F6XK90 devices, read as ‘0’. 2010 Microchip Technology Inc. Preliminary DS39957B-page 163 PIC18F87K90 FAMILY 11.5 PORTD, TRISD and LATD Registers I/O port functionality is only available when the LCD segments are disabled. PORTD is an 8-bit wide, bidirectional port. The corresponding Data Direction and Output Latch registers are TRISD and LATD. All pins on PORTD are implemented with Schmitt Trigger input buffers. Each pin is individually configurable as an input or output. Note: These pins are configured as digital inputs on any device Reset. Each of the PORTD pins has a weak internal pull-up. A single control bit can turn off all the pull-ups. This is performed by clearing bit, RDPU (PADCFG1<7>). The weak pull-up is automatically turned off when the port pin is configured as an output. The pull-ups are disabled on all device Resets. All of the PORTD pins are multiplexed with LCD segment drives that are controlled by bits in the LCDSE0 register. RD0 is multiplexed with the CTMU pulse generator output. DS39957B-page 164 The PORTD also has the I2C and SPI functionality on RD4, RD5 and RD6. The pins for SPI are also configurable for open-drain output. Open-drain configuration is selected by setting the SSPxOD control bits in the ODCON1 register. RD0 has a CTMU functionality. RD1 has the functionality for a Timer5 clock input and also Timer7 has functionality for an external clock gate input. EXAMPLE 11-4: CLRF PORTD CLRF LATD MOVLW 0CFh MOVWF TRISD Preliminary INITIALIZING PORTD ; ; ; ; ; ; ; ; ; ; ; ; Initialize PORTD by clearing output data latches Alternate method to clear output data latches Value used to initialize data direction Set RD<3:0> as inputs RD<5:4> as outputs RD<7:6> as inputs 2010 Microchip Technology Inc. PIC18F87K90 FAMILY TABLE 11-7: Pin Name RD0/SEG0/ CTPLS PORTD FUNCTIONS Function TRIS Setting I/O I/O Type RD0 0 O DIG SEG0 RD1/SEG1/ T5CKI/T7G RD2/SEG2 RD3/SEG3 RD4/SEG4/ SDO2 RD5/SEG5/ SDI2/SDA2 RD6/SEG6/ SCK2/SCL2 Legend: I ST 1 O ANA LATD<0> data output. PORTD<0> data input. LCD Segment 0 output; disables all other pin functions. CTPLS x O DIG CTMU pulse generator output. RD1 0 O DIG LATD<1> data output. 1 I ST SEG1 1 O ANA T5CKI x I ST Timer5 clock input. T7G x I ST Timer7 external clock gate input. RD2 0 O DIG LATD<2> data output. 1 I ST SEG2 1 O ANA LCD Segment 2 output; disables all other pin functions. RD3 0 O DIG LATD<3> data output. PORTD<1> data input. LCD Segment 1 output; disables all other pin functions. PORTD<2> data input. 1 I ST SEG3 1 O ANA LCD Segment 3 output; disables all other pin functions. RD4 0 O DIG LATD<4> data output. 1 I ST PORTD<4> data input. PORTD<3> data input. SEG4 1 O ANA SDO2 0 P DOG SPI data output (MSSP module). RD5 0 O DIG LATD<5> data output. 1 I ST PORTD<5> data input. SEG5 1 O ANA SDI2 1 I ST SPI data input (MSSP module). SDA2 0 O I2C I2C™ data input (MSSP module). Input type depends on module setting. 1 I ANA LCD Segment 5 output; disables all other pin functions. 0 O DIG LATD<6> data output. 1 I ST SEG6 1 O ANA LCD Segment 6 output; disables all other pin functions. SCK2 0 O DIG SPI clock output (MSSP module). Takes priority over port data. RD6 SCL2 RD7/SEG7/ SS2 1 Description RD7 LCD Segment 4 output; disables all other pin functions. LCD Segment 5 output; disables all other pin functions. PORTD<6> data input. 1 I ST SPI clock input (MSSP module). 0 O DIG I2C clock output (MSSP module). Takes priority over port data. 1 I I2C I2C clock input (MSSP module). Input type depends on module setting. 0 O DIG LATD<7> data output. 1 I ST SEG7 1 I ANA LCD Segment 7 output; disables all other pin functions. PORTD<7> data input. SS2 1 I TTL Slave select input for MSSP module. O = Output, I = Input, ANA = Analog Signal, DIG = Digital Output, ST = Schmitt Trigger Buffer Input, I2C = I2C Buffer Input, x = Don’t care (TRIS bit does not affect port direction or is overridden for this option). 2010 Microchip Technology Inc. Preliminary DS39957B-page 165 PIC18F87K90 FAMILY TABLE 11-8: Name PORTD SUMMARY OF REGISTERS ASSOCIATED WITH PORTD Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Reset Values on Page: RD7 RD6 RD5 RD4 RD3 RD2 RD1 RD0 76 LATD LATD7 LATD6 LATD5 LATD4 LATD3 LATD2 LATD1 LATD0 76 TRISD TRISD7 TRISD6 TRISD5 TRISD4 TRISD3 TRISD2 TRISD1 TRISD0 76 SE02 SE01 SE00 81 — 78 LCDSE0 SE07 SE06 SE05 SE04 SE03 PADCFG1 RDPU REPU RJPU(1) — — RTSECSEL1 RTSECSEL0 Legend: Shaded cells are not used by PORTD. Note 1: Not available on 64-pin devices. DS39957B-page 166 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 11.6 PORTE, TRISE and LATE Registers PORTE is a 8-bit wide, bidirectional port. The corresponding Data Direction and Output Latch registers are TRISE and LATE. All pins on PORTE are implemented with Schmitt Trigger input buffers. Each pin is individually configurable as an input or output. The RE7 pin is also configurable for open-drain output when ECCP2 is active on this pin. Open-drain configuration is selected by setting the CCP2OD control bit (ODCON1<6>) Note: These pins are configured as digital inputs on any device Reset. Pins, RE2, RE1 and RE0, are multiplexed with the functions of LCDBIAS3, LCDBIAS2 and LCDBIAS1. When LCD bias generation is required (in any application where the device is connected to an external LCD), these pins cannot be used as digital I/O. These pins can be used as digital I/O, however, when the internal resistor ladder is used for bias generation. PORTE is also multiplexed with Enhanced PWM outputs, B and C for ECCP1 and ECCP3, and outputs, B, C and D for ECCP2. For all devices, their default assignments are on PORTE<6:0>. On 80-pin devices, the multiplexing for the outputs of ECCP1 and ECCP3 is controlled by the ECCPMX Configuration bit. Clearing this bit reassigns the P1B/P1C and P3B/P3C outputs to PORTH. Each of the PORTE pins has a weak internal pull-up. A single control bit can turn off all the pull-ups. This is performed by clearing bit, REPU (PADCFG1<6>). The weak pull-up is automatically turned off when the port pin is configured as an output. The pull-ups are disabled on any device Reset. RE7 is multiplexed with the LCD segment drive (SEG31) that is controlled by the LCDSE3<7> bit. I/O port function is only available when the segment is disabled. RE7 can also be configured as the alternate peripheral pin for the ECCP2 module. This is done by clearing the CCP2MX Configuration bit. Pins, RE<6:3>, are multiplexed with the LCD common drives. I/O port functions are available only on those PORTE pins according to which commons are active. The configuration is determined by the LMUX<1:0> control bits (LCDCON<1:0>). The availability is summarized in Table 11-9. RE3 can also be configured as the Reference Clock Output (REFO) from the system clock. For further details, refer to Section 3.7 “Reference Clock Output”. TABLE 11-9: LCDCON <1:0> PORTE PINS AVAILABLE IN DIFFERENT LCD DRIVE CONFIGURATIONS(1) EXAMPLE 11-5: CLRF PORTE CLRF LATE Active LCD Commons PORTE Pins Available for I/O MOVLW 03h 00 COM0 RE6, RE5, RE4 MOVWF TRISE 01 COM0, COM1 RE6, RE5 10 COM0, COM1 and COM2 RE6 11 All (COM0 through COM3) None Note 1: INITIALIZING PORTE ; ; ; ; ; ; ; ; ; ; ; Initialize PORTE by clearing output data latches Alternate method to clear output data latches Value used to initialize data direction Set RE<1:0> as inputs RE<7:2> as outputs If the LCD bias voltages are generated using the internal resistor ladder, the LCDBIASx pins are also available as I/O ports (RE0, RE1 and RE2). 2010 Microchip Technology Inc. Preliminary DS39957B-page 167 PIC18F87K90 FAMILY TABLE 11-10: PORTE FUNCTIONS Pin Name Function TRIS Setting I/O I/O Type RE0/LCDBIAS1/ P2D RE0 0 O DIG LATE<0> data output. 1 I ST PORTE<0> data input. LCDBIAS1 — I ANA P2D 0 O — RE1 0 O DIG LATE<1> data output. 1 I ST PORTE<1> data input. LCDBIAS2 — I ANA P2C 0 O — RE2 0 O DIG RE1/LCDBIAS2/ P2C RE2/LCDBIAS3/ P2B I ST x I ANA P2B 0 O — RE3 0 O DIG 1 I ST COM0 x O ANA P3C 0 O — CCP9 0 O DIG RE5/COM2/ P1C/CCP7 Legend: Note 1: LATE<2> data output. PORTE<2> data input. LCD module bias voltage input. ECCP2 PWM Output B. May be configured for tri-state during Enhanced PWM shutdown events. LATE<3> data output. PORTE<3> data input. LCD Common 0 output; disables all other outputs. ECCP3 PWM Output C. May be configured for tri-state during Enhanced PWM shutdown events. CCP9 compare/PWM output. Takes priority over port data. 1 I ST CCP9 capture input. REFO x O DIG Reference output clock. RE4 0 O DIG LATE<4> data output. 1 I ST PORTE<4> data input. COM1 x O ANA P3B 0 O — CCP8 0 O DIG 1 I ST CCP8 capture input. 0 O DIG LATE<5> data output. 1 I ST PORTE<5> data input. RE5 RE6/COM3/ P1B/CCP6 LCD module bias voltage input. ECCP2 PWM Output C. May be configured for tri-state during Enhanced PWM shutdown events. 1 RE4/COM1/ P3B/CCP8 LCD module bias voltage input. ECCP2 PWM Output D. May be configured for tri-state during Enhanced PWM shutdown events. LCDBIAS3 RE3/COM0/ P3C/CCP9/ REFO Description LCD Common 1 output; disables all other outputs. ECCP3 PWM Output B. May be configured for tri-state during Enhanced PWM shutdown events. CCP8 Compare/PWM output. Takes priority over port data. COM2 x O ANA P1C 0 O — CCP7 0 O DIG 1 I ST CCP7 capture input. 0 O DIG LATE<6> data output. 1 I ST PORTE<6> data input. RE6 LCD Common 2 output; disables all other outputs. ECCP1 PWM Output C. May be configured for tri-state during Enhanced PWM shutdown events. CCP7 Compare/PWM output. Takes priority over port data. COM3 x O ANA P1B 0 O — LCD Common 3 output; disables all other outputs. CCP6 0 O DIG CCP6 Compare/PWM output. Takes priority over port data. 1 I ST CCP9 capture input. ECCP1 PWM Output B. May be configured for tri-state during Enhanced PWM shutdown events. O = Output, I = Input, ANA = Analog Signal, DIG = Digital Output, ST = Schmitt Trigger Buffer Input, x = Don’t care (TRIS bit does not affect port direction or is overridden for this option). Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared. DS39957B-page 168 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY TABLE 11-10: PORTE FUNCTIONS (CONTINUED) Pin Name Function TRIS Setting I/O I/O Type RE7 0 O DIG RE7/ECCP2/ P2A/SEG31 ECCP2(1) Legend: Note 1: Description LATE<7> data output. 1 I ST PORTE<7> data input. 0 O DIG ECCP2 compare/PWM output; takes priority over port data. 1 I ST ECCP2 capture input. P2A 0 O — ECCP2 PWM Output A. May be configured for tri-state during Enhanced PWM shutdown event. SEG31 1 O ANA Segment 31 analog output for LCD; disables digital output. O = Output, I = Input, ANA = Analog Signal, DIG = Digital Output, ST = Schmitt Trigger Buffer Input, x = Don’t care (TRIS bit does not affect port direction or is overridden for this option). Alternate assignment for ECCP2 when the CCP2MX Configuration bit is cleared. TABLE 11-11: SUMMARY OF REGISTERS ASSOCIATED WITH PORTE Name PORTE Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Reset Values on Page: RE7 RE6 RE5 RE4 RE3 RE2 RE1 RE0 76 LATE LATE7 LATE6 LATE5 LATE4 LATE3 LATE2 LATE1 LATE0 76 TRISE TRISE7 TRISE6 TRISE5 TRISE4 TRISE3 TRISE2 TRISE1 TRISE0 76 LCDCON LCDEN SLPEN WERR — CS1 CS0 LMUX1 LMUX0 81 SE30 SE29 SE28 SE27 SE26 SE25 SE24 81 — — — — SSP2OD 79 CCP5OD CCP4OD CCP3OD 79 — 78 LCDSE3 SE31 ODCON1 SSP1OD ODCON2 CCP10OD CCP9OD CCP8OD CCP7OD CCP6OD PADCFG1 RDPU CCP2OD CCP1OD REPU RJPU(1) — — RTSECSEL1 RTSECSEL0 Legend: Shaded cells are not used by PORTE. Note 1: Not available on 64-pin devices. 2010 Microchip Technology Inc. Preliminary DS39957B-page 169 PIC18F87K90 FAMILY 11.7 PORTF, LATF and TRISF Registers PORTF is a 7-bit wide, bidirectional port. The corresponding Data Direction and Output Latch registers are TRISF and LATF. All pins on PORTF are implemented with Schmitt Trigger input buffers. Each pin is individually configurable as an input or output. PORTF is multiplexed with analog peripheral functions, as well as LCD segments. Pins, RF1 through RF6, may be used as comparator inputs or outputs by setting the appropriate bits in the CMCON register. To use RF<7:1> as digital inputs, it is also necessary to turn off the comparators. Note 1: On device Resets, pins, RF<7:1>, are configured as analog inputs and are read as ‘0’. 2: To configure PORTF as a digital I/O, turn off the comparators and clear ANCON1 and ANCON2 to digital. DS39957B-page 170 PORTF is also multiplexed with LCD segment drives controlled by bits in the LCDSE2 and LCDSE3 registers. I/O port functions are only available when the segments are disabled. EXAMPLE 11-6: CLRF PORTF CLRF LATF BANKSEL MOVLW MOVWF MOVLW ANCON1 01Fh ANCON1 0F0h MOVWF MOVLW ANCON2 0CEh MOVWF TRISF Preliminary INITIALIZING PORTF ; ; ; ; ; ; Initialize PORTF by clearing output data latches Alternate method to clear output data latches ; Make AN6, AN7 and AN5 digital ; ; Make AN8, AN9, AN10 and AN11 digital ; Set PORTF as digital I/O ; Value used to ; initialize data ; direction ; Set RF3:RF1 as inputs ; RF5:RF4 as outputs ; RF7:RF6 as inputs 2010 Microchip Technology Inc. PIC18F87K90 FAMILY TABLE 11-12: PORTF FUNCTIONS Pin Name Function TRIS Setting I/O I/O Type RF1/AN6/C2OUT/ SEG19/CTDIN RF1 0 O DIG 1 I ST 1 I ANA AN6 RF2/AN7/C1OUT/ SEG20 RF4/AN9/SEG22/ C2INA RF5/AN10/CVREF/ SEG23/C1INB RF6/AN11/SEG24/ C1INA Legend: PORTF<1> data input; disabled when analog input is enabled. A/D Input Channel 6. Default configuration on POR. 0 O DIG Comparator 2 output; takes priority over port data. SEG19 1 O ANA LCD Segment 19 output; disables all other pin functions. CTDIN 1 I ST CTMU pulse delay input. RF2 0 O DIG LATF<2> data output; not affected by analog input. 1 I ST 1 I ANA PORTF<2> data input; disabled when analog input is enabled. A/D Input Channel 7. Default configuration on POR. C1OUT 0 O DIG Comparator 1 output; takes priority over port data. SEG20 1 O ANA LCD Segment 20 output; disables all other pin functions. RF3 0 O DIG LATF<3> data output; not affected by analog input. 1 I ST PORTF<3> data input; disabled when analog input is enabled. AN8 1 I ANA A/D Input Channel 8 and Comparator C2+ input. Default input configuration on POR; not affected by analog output. SEG21 1 O ANA LCD Segment 21 output; disables all other pin functions. Comparator 2 Input B. C2INB 1 I ANA CTMUI x O — RF4 0 O DIG LATF<4> data output; not affected by analog input. 1 I ST PORTF<4> data input; disabled when analog input is enabled. AN9 1 I ANA A/D Input Channel 9 and Comparator C2- input. Default input configuration on POR; does not affect digital output. SEG22 1 O ANA LCD Segment 22 output; disables all other pin functions. C2INA 1 I ANA Comparator 2 Input A. RF5 0 O DIG LATF<5> data output; not affected by analog input. Disabled when CVREF output is enabled. 1 I ST PORTF<5> data input; disabled when analog input is enabled. Disabled when CVREF output is enabled. AN10 1 I ANA A/D Input Channel 10 and Comparator C1+ input. Default input configuration on POR. CVREF x O ANA Comparator voltage reference output. Enabling this feature disables digital I/O. SEG23 1 O ANA LCD Segment 23 output; disables all other pin functions. C1INB 1 I ANA Comparator 1 Input B. RF6 0 O DIG LATF<6> data output; not affected by analog input. 1 I ST PORTF<6> data input; disabled when analog input is enabled. 1 I ANA A/D Input Channel 11 and Comparator C1- input. Default input configuration on POR; does not affect digital output. SEG24 1 O ANA LCD Segment 24 output; disables all other pin functions. C1INA 1 I ANA Comparator 1 Input A. RF7 0 O DIG LATF<7> data output; not affected by analog input. AN11 RF7/AN5/SS1/ SEG25 LATF<1> data output; not affected by analog input. C2OUT AN7 RF3/AN8/SEG21/ C2INB/CTMUI Description CTMU pulse generator charger for the C2INB comparator input. 1 I ST AN5 1 I ANA A/D Input Channel 5. Default configuration on POR. PORTF<7> data input; disabled when analog input is enabled. SS1 1 I TTL Slave select input for MSSP module. SEG25 1 O ANA LCD Segment 25 output; disables all other pin functions. O = Output, I = Input, ANA = Analog Signal, DIG = Digital Output, ST = Schmitt Trigger Buffer Input, TTL = TTL Buffer Input, x = Don’t care (TRIS bit does not affect port direction or is overridden for this option). 2010 Microchip Technology Inc. Preliminary DS39957B-page 171 PIC18F87K90 FAMILY TABLE 11-13: SUMMARY OF REGISTERS ASSOCIATED WITH PORTF Name PORTF Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Reset Values on Page: RF7 RF6 RF5 RF4 RF3 RF2 RF1 — 76 76 LATF LATF7 LATF6 LATF5 LATF4 LATF3 LATF2 LATF1 — TRISF TRISF7 TRISF6 TRISF5 TRISF4 TRISF3 TRISF2 TRISF1 — 76 ANSEL4 ANSEL3 ANSEL2 ANCON0 ANSEL7 ANSEL6 ANSEL5 ANSEL1 ANSEL0 79 ANCON1 ANSEL15 ANSEL14 ANSEL13 ANSEL12 ANSEL11 ANSEL10 ANSEL9 ANSEL8 79 CMSTAT CMP3OUT CMP2OUT CMP1OUT — — — — — 75 CVRCON CVREN CVROE CVRR CVRSS CVR3 CVR2 CVR1 CVR0 75 LCDSE2 SE23 SE22 SE21 SE20 SE19 SE18 SE17 SE16 81 LCDSE3 SE31 SE30 SE29 SE28 SE27 SE26 SE25 SE24 81 Legend: — = unimplemented, read as ‘0’. Shaded cells are not used by PORTF. DS39957B-page 172 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 11.8 PORTG, TRISG and LATG Registers PORTG is a 5-bit wide, bidirectional port. The corresponding Data Direction and Output Latch registers are TRISG and LATG. PORTG is multiplexed with EUSART, LCD and CCP/ECCP/Analog/Comparator/RTCC/Timer input functions (Table 11-14). When operating as I/O, all PORTG pins have Schmitt Trigger input buffers. The open-drain functionality for the CCPx and UART can be configured using ODCONx. RG4 is multiplexed with LCD segment drives controlled by bits in the LCDSE2 register and as the RG4/SEG26/RTCC/T7XKI/T5G/CCP5/AN16/P1D/C3INC pin. The I/O port function is only available when the segments are disabled. The RG5 pin is multiplexed with the MCLR pin and is available only as an input port. To configure this port for input only, set the MCLRE pin (CONFIG3H<7>). When enabling peripheral functions, care should be taken in defining TRIS bits for each PORTG pin. Some peripherals override the TRIS bit to make a pin an output, while other peripherals override the TRIS bit to make a pin an input. The user should refer to the corresponding peripheral section for the correct TRIS bit settings. The pin override value is not loaded into the TRIS register. This allows read-modify-write of the TRIS register without concern due to peripheral overrides. EXAMPLE 11-7: INITIALIZING PORTG CLRF PORTG BCF CM1CON, CON CLRF LATG BANKSEL ANCON2 MOVLW 0F0h MOVWF MOVLW ANCON2 04h MOVWF TRISG ; ; ; ; ; ; ; ; Initialize PORTG by clearing output data latches disable comparator 1 Alternate method to clear output data latches ; make AN16 to AN19 ; digital ; ; ; ; ; ; ; Value used to initialize data direction Set RG1:RG0 as outputs RG2 as input RG4:RG3 as inputs TABLE 11-14: PORTG FUNCTIONS Pin Name RG0/ECCP3/ P3A Function TRIS Setting I/O I/O Type RG0 0 O DIG 1 I ST PORTG<0> data input. 0 O DIG ECCP3 compare output and ECCP3 PWM output. Takes priority over port data. ECCP3 RG1/TX2/CK2/ AN19/C3OUT Legend: Description LATG<0> data output. 1 I ST ECCP3 capture input. P3A 0 O — ECCP3 PWM Output A. May be configured for tri-state during Enhanced PWM shutdown events. RG1 0 O DIG LATG<1> data output. 1 I ST PORTG<1> data input. TX2 1 O DIG Synchronous serial data output (EUSART module); takes priority over port data. CK2 1 O DIG Synchronous serial data input (EUSART module); user must configure as an input. 1 I ST AN19 1 I ANA A/D Input Channel 19. Default input configuration on POR. Does not affect digital output. Synchronous serial clock input (EUSART module). C3OUT x O DIG Comparator 3 output. O = Output, I = Input, ANA = Analog Signal, DIG = Digital Output, ST = Schmitt Trigger Buffer Input, x = Don’t care (TRIS bit does not affect port direction or is overridden for this option). 2010 Microchip Technology Inc. Preliminary DS39957B-page 173 PIC18F87K90 FAMILY TABLE 11-14: PORTG FUNCTIONS (CONTINUED) Pin Name Function TRIS Setting I/O I/O Type RG2 0 O DIG LATG<2> data output. PORTG<2> data input. RG2/RX2/DT2/ AN18/C3INA RG3/CCP4/AN17/ P3D/C3INB 1 I ST RX2 1 I ST Asynchronous serial receive data input (EUSART module). DT2 1 O DIG Synchronous serial data output (EUSART module); takes priority over port data. 1 I ST Synchronous serial data input (EUSART module); user must configure as an input. AN18 1 I ANA A/D Input Channel 18. Default input configuration on POR. Does not affect digital output. C3INA x I ANA Comparator 3 Input A. RG3 0 O DIG LATG<3> data output. 1 I ST PORTG<3> data input. 0 O DIG CCP4 compare/PWM output. Takes priority over port data. 1 I ST CCP4 capture input. AN17 1 I ANA A/D Input Channel 17. Default input configuration on PR. Does not affect digital output. C3INB x I ANA Comparator 3 Input B. P3D 0 O — RG4 0 O DIG CCP4 RG4/SEG26/ RTCC/T7CKI/ T5G/CCP5/ AN16/P1D/ C3INC ECCP3 PWM Output D. May be configured for tri-state during Enhanced PWM. LATG<4> data output. 1 I ST SEG26 1 O ANA LCD Segment 26 output; disables all other pin functions. PORTG<4> data input. RTCC x O DIG RTCC output. T7CKI x I ST Timer7 clock input. T5G x I ST Timer5 external clock gate input. CCP5 0 O DIG CCP5 compare/PWM output. Takes priority over port data. 1 I ST AN16 1 I ANA A/D Input Channel 17. Default input configuration on POR. Does not affect digital output. C3INC x I ANA Comparator 3 Input C. P1D 0 O — ECCP1 PWM Output D. May be configured for tri-state during Enhanced PWM. I ST See the MCLR/RG5 pin. RG5 Legend: Description CCP5 capture input. O = Output, I = Input, ANA = Analog Signal, DIG = Digital Output, ST = Schmitt Trigger Buffer Input, x = Don’t care (TRIS bit does not affect port direction or is overridden for this option). TABLE 11-15: SUMMARY OF REGISTERS ASSOCIATED WITH PORTG Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Reset Values on Page: PORTG — — RG5(1) RG4 RG3 RG2 RG1 RG0 76 TRISG — — — TRISG4 TRISG3 TRISG2 TRISG1 TRISG0 76 SE31 SE30 SE29 SE28 SE27 SE26 SE25 SE24 81 Name LCDSE3 ANCON2 ANSEL23 ANSEL22 ANSEL21 ANSEL20 ANSEL19 ANSEL18 ANSEL17 ANSEL16 — — — — 79 ODCON1 SSP1OD CCP2OD CCP1OD SSP2OD 79 ODCON2 CCP10OD CCP9OD CCP8OD CCP7OD CCP6OD CCP5OD CCP4OD CCP3OD 79 Legend: — = unimplemented, read as ‘0’. Shaded cells are not used by PORTG. Note 1: Bit is available when Master Clear is disabled (MCLRE = 0). When MCLRE is set, the bit is unimplemented. DS39957B-page 174 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 11.9 Note: PORTH, LATH and TRISH Registers EXAMPLE 11-8: PORTH is available only on the 80-pin devices. PORTH is an 8-bit wide, bidirectional I/O port. The corresponding Data Direction and Output Latch registers are TRISH and LATH. All pins on PORTH are implemented with Schmitt Trigger input buffers. Each pin is individually configurable as an input or output. All PORTH pins are multiplexed with the ADC/CCP/Comparator and LCD segment drives controlled by the LCDSE5 register. I/O port functions are only available when the segments are disabled. 2010 Microchip Technology Inc. CLRF PORTH CLRF LATH BANKSEL MOVLW MOVWF MOVLW MOVWF MOVLW ANCON2 0Fh ANCON2 0Fh ANCON1 0CFh MOVWF TRISH Preliminary INITIALIZING PORTH ; ; ; ; ; ; Initialize PORTH by clearing output data latches Alternate method to clear output data latches ; ; ; ; ; ; ; ; ; ; Configure PORTH as digital I/O Configure PORTH as digital I/O Value used to initialize data direction Set RH3:RH0 as inputs RH5:RH4 as outputs RH7:RH6 as inputs DS39957B-page 175 PIC18F87K90 FAMILY TABLE 11-16: PORTH FUNCTIONS Pin Name Function TRIS Setting I/O I/O Type RH0 0 O DIG RH0/SEG47/ AN23 RH1/SEG46/ AN22 RH2/SEG45/ AN21 RH3/SEG44/ AN20 RH4/SEG40/ CCP9/P3C/ AN12/C2INC RH5/SEG41/ CCP8/P3B/ AN13/C2IND Legend: Description LATH<0> data output. 1 I ST SEG47 1 O ANA LCD Segment 47 output; disables all other pin functions. PORTH<0> data input. AN23 1 I ANA A/D Input Channel 23. Default input configuration on POR. Does not affect digital input. RH1 0 O DIG LATH<1> data output. 1 I ST SEG46 1 O ANA LCD Segment 46 output; disables all other pin functions. AN22 1 I ANA A/D Input Channel 22. Default input configuration on POR. Does not affect digital input. RH2 0 O DIG LATH<2> data output. PORTH<1> data input. 1 I ST SEG45 1 O ANA LCD Segment 45 output; disables all other pin functions. AN21 1 I ANA A/D Input Channel 21. Default input configuration on POR. Does not affect digital input. LATH<3> data output. RH3 PORTH<2> data input. 0 O DIG 1 I ST SEG44 1 O ANA LCD Segment 44 output; disables all other pin functions. AN20 1 I ANA A/D Input Channel 20. Default input configuration on POR. Does not affect digital input. RH4 0 O DIG LATH<4> data output. PORTH<3> data input. 1 I ST SEG40 1 O ANA LCD Segment 40 output; disables all other pin functions. PORTH<4> data input. CCP9 0 O DIG CCP9 compare/PWM output. Takes priority over port data. 1 I ST CCP9 capture input. P3C 0 O — ECCP3 PWM Output C. May be configured for tri-state during Enhanced PWM. AN12 1 I ANA A/D Input Channel 12. Default input configuration on POR. Does not affect digital input. C2INC x I ANA Comparator 2 Input C. RH5 0 O DIG LATH<5> data output. 1 I ST SEG41 1 O ANA LCD Segment 41 output; disables all other pin functions. PORTH<5> data input. CCP8 0 O DIG CCP8 compare/PWM output. Takes priority over port data. 1 I ST CCP8 capture input. P3B 0 O — ECCP3 PWM Output B. May be configured for tri-state during Enhanced PWM. AN13 1 I ANA A/D Input Channel 13. Default input configuration on POR. Does not affect digital input. C2IND x I ANA Comparator 2 Input D. O = Output, I = Input, ANA = Analog Signal, DIG = Digital Output, ST = Schmitt Trigger Buffer Input, x = Don’t care (TRIS bit does not affect port direction or is overridden for this option). DS39957B-page 176 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY TABLE 11-16: PORTH FUNCTIONS (CONTINUED) Pin Name RH6/SEG42/ CCP7/P1C/ AN14/C1INC RH7/SEG43/ CCP6/P1B/ AN15 Legend: Function TRIS Setting I/O I/O Type RH6 0 O DIG Description LATH<6> data output. 1 I ST SEG42 1 O ANA LCD Segment 42 output; disables all other pin functions. PORTH<6> data input. CCP7 0 O DIG CCP7 compare/PWM output. Takes priority over port data. 1 I ST CCP7 capture input. P1C 0 O — ECCP1 PWM Output C. May be configured for tri-state during Enhanced PWM. AN14 1 I ANA A/D Input Channel 14. Default input configuration on POR. Does not affect digital input. C1INC x I ANA Comparator 1 Input C. RH7 0 O DIG LATH<7> data output. 1 I ST SEG43 1 O ANA LCD Segment 43 output; disables all other pin functions. PORTH<7> data input. CCP6 0 O DIG CCP6 compare/PWM output. Takes priority over port data. 1 I ST CCP6 capture input. P1B 0 O — ECCP1 PWM Output B. May be configured for tri-state during Enhanced PWM. AN15 1 I ANA A/D Input Channel 15. Default input configuration on POR. Does not affect digital input. O = Output, I = Input, ANA = Analog Signal, DIG = Digital Output, ST = Schmitt Trigger Buffer Input, x = Don’t care (TRIS bit does not affect port direction or is overridden for this option). TABLE 11-17: SUMMARY OF REGISTERS ASSOCIATED WITH PORTH Name PORTH Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Reset Values on Page: RH7 RH6 RH5 RH4 RH3 RH2 RH1 RH0 76 LATH LATH7 LATH6 LATH5 LATH4 LATH3 LATH2 LATH1 LATH0 76 TRISH TRISH7 TRISH6 TRISH5 TRISH4 TRISH3 TRISH2 TRISH1 TRISH0 76 SE47 SE46 SE45 SE44 SE43 SE42 SE41 SE40 81 LCDSE5 ANCON1 ANSEL15 ANSEL14 ANSEL13 ANSEL12 ANSEL11 ANSEL10 ANSEL9 ANSEL8 79 ANCON2 ANSEL23 ANSEL22 ANSEL21 ANSEL20 ANSEL19 ANSEL18 ANSEL17 ANSEL16 79 ODCON2 CCP10OD CCP9OD CCP8OD CCP7OD CCP6OD CCP5OD CCP4OD CCP3OD 79 2010 Microchip Technology Inc. Preliminary DS39957B-page 177 PIC18F87K90 FAMILY 11.10 PORTJ, TRISJ and LATJ Registers Note: PORTJ is available only on 80-pin devices. PORTJ is an 8-bit wide, bidirectional port. The corresponding Data Direction and Output Latch registers are TRISJ and LATJ. All pins on PORTJ are implemented with Schmitt Trigger input buffers. Each pin is individually configurable as an input or output. Note: These pins are configured as digital inputs on any device Reset. All PORTJ pins except RJ0 are multiplexed with LCD segment drives controlled by the LCDSE4 register. I/O port functions are only available on these pins when the segments are disabled. DS39957B-page 178 Each of the PORTJ pins has a weak internal pull-up. The pull-ups are provided to keep the inputs at a known state for the external memory interface while powering up. A single control bit can turn off all the pull-ups. This is performed by clearing bit RJPU (PADCFG1<5>). The weak pull-up is automatically turned off when the port pin is configured as an output. The pull-ups are disabled on any device Reset. EXAMPLE 11-9: CLRF PORTJ CLRF LATJ MOVLW 0CFh MOVWF TRISJ Preliminary INITIALIZING PORTJ ; ; ; ; ; ; ; ; ; ; Initialize PORTJ by clearing output latches Alternate method to clear output latches Value used to initialize data direction Set RJ3:RJ0 as inputs RJ5:RJ4 as output RJ7:RJ6 as inputs 2010 Microchip Technology Inc. PIC18F87K90 FAMILY TABLE 11-18: PORTJ FUNCTIONS Function TRIS Setting I/O I/O Type RJ0 RJ0 0 O DIG 1 I ST PORTJ<0> data input. RJ1/SEG33 RJ1 0 O DIG LATJ<1> data output. Pin Name LATJ<0> data output. 1 I ST SEG33 1 O ANA LCD Segment 33 output; disables all other pin functions. RJ2 0 O DIG LATJ<2> data output. 1 I ST SEG34 1 O ANA LCD Segment 34 output; disables all other pin functions. RJ3 0 O DIG LATJ<3> data output. RJ2/SEG34 RJ3/SEG35 PORTJ<1> data input. PORTJ<2> data input. 1 I ST SEG35 1 O ANA LCD Segment 35 output; disables all other pin functions. RJ4 0 O DIG LATJ<4> data output. 1 I ST PORTJ<4> data input. SEG39 1 O ANA LCD Segment 39 output; disables all other pin functions. RJ5 0 O DIG LATJ<5> data output. RJ4/SEG39 RJ5/SEG38 PORTJ<3> data input. 1 I ST SEG38 1 O ANA LCD Segment 38 output; disables all other pin functions. RJ6 0 O DIG LATJ<6> data output. 1 I ST SEG37 1 O ANA LCD Segment 37 output; disables all other pin functions. RJ7 0 O DIG LATJ<7> data output. 1 I ST 1 O ANA RJ6/SEG37 RJ7/SEG36 SEG36 Legend: Description PORTJ<5> data input. PORTJ<6> data input. PORTJ<7> data input. LCD Segment 36 output; disables all other pin functions. O = Output, I = Input, ANA = Analog Signal, DIG = Digital Output, ST = Schmitt Trigger Buffer Input, x = Don’t care (TRIS bit does not affect port direction or is overridden for this option). TABLE 11-19: SUMMARY OF REGISTERS ASSOCIATED WITH PORTJ Name PORTJ Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Reset Values on Page: RJ7 RJ6 RJ5 RJ4 RJ3 RJ2 RJ1 RJ0 76 LATJ LATJ7 LATJ6 LATJ5 LATJ4 LATJ3 LATJ2 LATJ1 LATJ0 76 TRISJ TRISJ7 TRISJ6 TRISJ5 TRISJ4 TRISJ3 TRISJ2 TRISJ1 TRISJ0 76 81 78 LCDSE4 PADCFG1 SE39 RDPU SE38 SE37 SE36 SE35 SE34 SE33 SE32 REPU RJPU(1) — — RTSECSEL1 RTSECSEL0 — Legend: Shaded cells are not used by PORTJ. Note 1: Unimplemented on PIC18F6XK90 devices, read as ‘0’. 2010 Microchip Technology Inc. Preliminary DS39957B-page 179 PIC18F87K90 FAMILY NOTES: DS39957B-page 180 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 12.0 TIMER0 MODULE The Timer0 module incorporates the following features: • Software-selectable operation as a timer or counter in both 8-bit or 16-bit modes • Readable and writable registers • Dedicated 8-bit, software programmable prescaler • Selectable clock source (internal or external) • Edge select for external clock • Interrupt-on-overflow REGISTER 12-1: The T0CON register (Register 12-1) controls all aspects of the module’s operation, including the prescale selection. It is both readable and writable. Figure 12-1 provides a simplified block diagram of the Timer0 module in 8-bit mode. Figure 12-2 provides a simplified block diagram of the Timer0 module in 16-bit mode. T0CON: TIMER0 CONTROL REGISTER R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 TMR0ON T08BIT T0CS T0SE PSA T0PS2 T0PS1 T0PS0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 TMR0ON: Timer0 On/Off Control bit 1 = Enables Timer0 0 = Stops Timer0 bit 6 T08BIT: Timer0 8-Bit/16-Bit Control bit 1 = Timer0 is configured as an 8-bit timer/counter 0 = Timer0 is configured as a 16-bit timer/counter bit 5 T0CS: Timer0 Clock Source Select bit 1 = Transition on T0CKI pin input edge 0 = Internal clock (FOSC/4) bit 4 T0SE: Timer0 Source Edge Select bit 1 = Increment on high-to-low transition on the T0CKI pin 0 = Increment on low-to-high transition on the T0CKI pin bit 3 PSA: Timer0 Prescaler Assignment bit 1 = Timer0 prescaler is not assigned; Timer0 clock input bypasses the prescaler 0 = Timer0 prescaler is assigned; Timer0 clock input comes from the prescaler output bit 2-0 T0PS<2:0>: Timer0 Prescaler Select bits 111 = 1:256 Prescale value 110 = 1:128 Prescale value 101 = 1:64 Prescale value 100 = 1:32 Prescale value 011 = 1:16 Prescale value 010 = 1:8 Prescale value 001 = 1:4 Prescale value 000 = 1:2 Prescale value 2010 Microchip Technology Inc. Preliminary DS39957B-page 181 PIC18F87K90 FAMILY 12.1 Timer0 Operation Timer0 can operate as either a timer or a counter. The mode is selected with the T0CS bit (T0CON<5>). In Timer mode (T0CS = 0), the module increments on every clock by default unless a different prescaler value is selected (see Section 12.3 “Prescaler”). If the TMR0 register is written to, the increment is inhibited for the following two instruction cycles. The user can work around this by writing an adjusted value to the TMR0 register. The Counter mode is selected by setting the T0CS bit (= 1). In this mode, Timer0 increments either on every rising edge or falling edge of the T0CKI pin. The incrementing edge is determined by the Timer0 Source Edge Select bit, T0SE (T0CON<4>); clearing this bit selects the rising edge. Restrictions on the external clock input are discussed below. An external clock source can be used to drive Timer0; however, it must meet certain requirements to ensure that the external clock can be synchronized with the FIGURE 12-1: internal phase clock (TOSC). There is a delay between synchronization and the onset of incrementing the timer/counter. 12.2 Timer0 Reads and Writes in 16-Bit Mode TMR0H is not the actual high byte of Timer0 in 16-bit mode. It is actually a buffered version of the real high byte of Timer0, which is not directly readable nor writable. (See Figure 12-2.) TMR0H is updated with the contents of the high byte of Timer0 during a read of TMR0L. This provides the ability to read all 16 bits of Timer0 without having to verify that the read of the high and low byte were valid, due to a rollover between successive reads of the high and low byte. Similarly, a write to the high byte of Timer0 must also take place through the TMR0H Buffer register. The high byte is updated with the contents of TMR0H when a write occurs to TMR0L. This allows all 16 bits of Timer0 to be updated at once. TIMER0 BLOCK DIAGRAM (8-BIT MODE) FOSC/4 0 1 1 Programmable Prescaler T0CKI Pin T0SE T0CS 0 Sync with Internal Clocks Set TMR0IF on Overflow TMR0L (2 TCY Delay) 8 3 T0PS<2:0> 8 PSA Internal Data Bus Note: Upon Reset, Timer0 is enabled in 8-bit mode with clock input from T0CKI max. prescale. FIGURE 12-2: FOSC/4 TIMER0 BLOCK DIAGRAM (16-BIT MODE) 0 1 1 T0CKI Pin T0SE T0CS Programmable Prescaler 0 Sync with Internal Clocks TMR0 High Byte TMR0L 8 Set TMR0IF on Overflow (2 TCY Delay) 3 Read TMR0L T0PS<2:0> Write TMR0L PSA 8 8 TMR0H 8 8 Internal Data Bus Note: Upon Reset, Timer0 is enabled in 8-bit mode with clock input from T0CKI max. prescale. DS39957B-page 182 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 12.3 Prescaler 12.3.1 An 8-bit counter is available as a prescaler for the Timer0 module. The prescaler is not directly readable or writable. Its value is set by the PSA and T0PS<2:0> bits (T0CON<3:0>), which determine the prescaler assignment and prescale ratio. Clearing the PSA bit assigns the prescaler to the Timer0 module. When it is assigned, prescale values from 1:2 through 1:256 in power-of-two increments are selectable. When assigned to the Timer0 module, all instructions writing to the TMR0 register (for example, CLRF TMR0, MOVWF TMR0, BSF TMR0) clear the prescaler count. Note: Writing to TMR0 when the prescaler is assigned to Timer0 will clear the prescaler count but will not change the prescaler assignment. TABLE 12-1: Name SWITCHING PRESCALER ASSIGNMENT The prescaler assignment is fully under software control and can be changed “on-the-fly” during program execution. 12.4 Timer0 Interrupt The TMR0 interrupt is generated when the TMR0 register overflows from FFh to 00h in 8-bit mode, or from FFFFh to 0000h in 16-bit mode. This overflow sets the TMR0IF flag bit. The interrupt can be masked by clearing the TMR0IE bit (INTCON<5>). Before reenabling the interrupt, the TMR0IF bit must be cleared in software by the Interrupt Service Routine (ISR). Since Timer0 is shut down in Sleep mode, the TMR0 interrupt cannot awaken the processor from Sleep. REGISTERS ASSOCIATED WITH TIMER0 Bit 7 Bit 6 Bit 5 TMR0L Timer0 Register Low Byte TMR0H Timer0 Register High Byte INTCON GIE/GIEH PEIE/GIEL TMR0IE T0CON TMR0ON T08BIT Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Reset Values on Page: 74 74 T0CS INT0IE RBIE TMR0IF INT0IF RBIF 73 T0SE PSA T0PS2 T0PS1 T0PS0 74 Legend: — = unimplemented, read as ‘0’. Shaded cells are not used by Timer0. 2010 Microchip Technology Inc. Preliminary DS39957B-page 183 PIC18F87K90 FAMILY NOTES: DS39957B-page 184 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 13.0 TIMER1 MODULE The Timer1 timer/counter module incorporates these features: • Software-selectable operation as a 16-bit timer or counter • Readable and writable 8-bit registers (TMR1H and TMR1L) • Selectable clock source (internal or external) with device clock or SOSC oscillator internal options • Interrupt-on-overflow • Reset on ECCP Special Event Trigger • Timer with gated control REGISTER 13-1: Figure 13-1 displays a simplified block diagram of the Timer1 module. The SOSC oscillator can also be used as a low-power clock source for the microcontroller in power-managed operation. Timer1 can also work on the SOSC oscillator. Timer1 is controlled through the T1CON Control register (Register 13-1). It also contains the SOSC Oscillator Enable bit (SOSCEN). Timer1 can be enabled or disabled by setting or clearing control bit, TMR1ON (T1CON<0>). The FOSC clock source should not be used with the ECCP capture/compare features. If the timer will be used with the capture or compare features, always select one of the other timer clocking options. T1CON: TIMER1 CONTROL REGISTER R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 TMR1CS1 TMR1CS0 T1CKPS1 T1CKPS0 SOSCEN T1SYNC RD16 TMR1ON bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7-6 TMR1CS<1:0>: Timer1 Clock Source Select bits 10 = The Timer1 clock source is either a pin or an oscillator depending on the SOSCEN bit. SOSCEN = 0: External clock is from the T1CKI pin (on the rising edge). SOSCEN = 1: Crystal oscillator is on the SOSCI/SOSCO pins or an extended clock on SCKLI (depends on SOSCEL fuse, CONFIG1L<4:3>) 01 = Timer1 clock source is the system clock (FOSC)(1) 00 = Timer1 clock source is the instruction clock (FOSC/4) bit 5-4 T1CKPS<1:0>: Timer1 Input Clock Prescale Select bits 11 = 1:8 Prescale value 10 = 1:4 Prescale value 01 = 1:2 Prescale value 00 = 1:1 Prescale value bit 3 SOSCEN: SOSC Oscillator Enable bit 1 = SOSC is enabled for Timer1 (based on SOSCSEL fuses) 0 = SOSC is disabled for Timer1 The oscillator inverter and feedback resistor are turned off to eliminate power drain. bit 2 T1SYNC: Timer1 External Clock Input Synchronization Select bit TMR1CS<1:0> = 10: 1 = Do not synchronize the external clock input 0 = Synchronize the external clock input TMR1CS<1:0> = 0x: This bit is ignored. Timer1 uses the internal clock when TMR1CS<1:0> = 1x. bit 1 RD16: 16-Bit Read/Write Mode Enable bit 1 = Enables register read/write of Timer1 in one 16-bit operation 0 = Enables register read/write of Timer1 in two 8-bit operations bit 0 TMR1ON: Timer1 On bit 1 = Enables Timer1 0 = Stops Timer1 Note 1: The FOSC clock source should not be selected if the timer will be used with the ECCP capture/compare features. 2010 Microchip Technology Inc. Preliminary DS39957B-page 185 PIC18F87K90 FAMILY 13.1 Timer1 Gate Control Register The Timer1 Gate Control register (T1GCON), displayed in Register 13-2, is used to control the Timer1 gate. REGISTER 13-2: T1GCON: TIMER1 GATE CONTROL REGISTER(1) R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R-x R/W-0 R/W-0 TMR1GE T1GPOL T1GTM T1GSPM T1GGO/T1DONE T1GVAL T1GSS1 T1GSS0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 TMR1GE: Timer1 Gate Enable bit If TMR1ON = 0: This bit is ignored. If TMR1ON = 1: 1 = Timer1 counting is controlled by the Timer1 gate function 0 = Timer1 counts regardless of the Timer1 gate function bit 6 T1GPOL: Timer1 Gate Polarity bit 1 = Timer1 gate is active-high (Timer1 counts when gate is high) 0 = Timer1 gate is active-low (Timer1 counts when gate is low) bit 5 T1GTM: Timer1 Gate Toggle Mode bit 1 = Timer1 Gate Toggle mode is enabled 0 = Timer1 Gate Toggle mode is disabled and toggle flip-flop is cleared Timer1 gate flip-flop toggles on every rising edge. bit 4 T1GSPM: Timer1 Gate Single Pulse Mode bit 1 = Timer1 Gate Single Pulse mode is enabled and is controlling Timer1 gate 0 = Timer1 Gate Single Pulse mode is disabled bit 3 T1GGO/T1DONE: Timer1 Gate Single Pulse Acquisition Status bit 1 = Timer1 gate single pulse acquisition is ready, waiting for an edge 0 = Timer1 gate single pulse acquisition has completed or has not been started This bit is automatically cleared when T1GSPM is cleared. bit 2 T1GVAL: Timer1 Gate Current State bit Indicates the current state of the Timer1 gate that could be provided to TMR1H:TMR1L; unaffected by the Timer1 Gate Enable (TMR1GE) bit. bit 1-0 T1GSS<1:0>: Timer1 Gate Source Select bits 11 = Comparator 2 output 10 = Comparator 1 output 01 = TMR2 to match PR2 output 00 = Timer1 gate pin Note 1: Programming the T1GCON prior to T1CON is recommended. DS39957B-page 186 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 13.2 Timer1 Operation 13.3.2 The Timer1 module is an 8 or 16-bit incrementing counter that is accessed through the TMR1H:TMR1L register pair. When used with an internal clock source, the module is a timer and increments on every instruction cycle. When used with an external clock source, the module can be used as either a timer or counter. It increments on every selected edge of the external source. Timer1 is enabled by configuring the TMR1ON and TMR1GE bits in the T1CON and T1GCON registers, respectively. When the external clock source is selected, the Timer1 module may work as a timer or a counter. When enabled to count, Timer1 is incremented on the rising edge of the external clock input, T1CKI. Either of these external clock sources can be synchronized to the microcontroller system clock or they can run asynchronously. When used as a timer with a clock oscillator, an external, 32.768 kHz crystal can be used in conjunction with the dedicated internal oscillator circuit. Note: When SOSC is selected as a Crystal mode (by SOSCEL), the RC1/SOSCI/ECCP2/P2A/SEG32 and RC0/SOSCO/SCLKI pins become inputs. This means the values of TRISC<1:0> are ignored and the pins are read as ‘0’. 13.3 Clock Source Selection The TMR1CS<1:0> and SOSCEN bits of the T1CON register are used to select the clock source for Timer1. Register 13-1 displays the clock source selections. 13.3.1 EXTERNAL CLOCK SOURCE In Counter mode, a falling edge must be registered by the counter prior to the first incrementing rising edge after any one or more of the following conditions: • Timer1 is enabled after a POR Reset • Write to TMR1H or TMR1L • Timer1 is disabled • Timer1 is disabled (TMR1ON = 0) When T1CKI is high, Timer1 is enabled (TMR1ON = 1) when T1CKI is low. INTERNAL CLOCK SOURCE When the internal clock source is selected, the TMR1H:TMR1L register pair will increment on multiples of FOSC as determined by the Timer1 prescaler. TABLE 13-1: TIMER1 CLOCK SOURCE SELECTION TMR1CS1 TMR1CS0 SOSCEN 0 1 x Clock Source (FOSC) 0 0 x Instruction Clock (FOSC/4) 1 0 0 External Clock on T1CKI Pin 1 0 1 Oscillator Circuit on SOSCI/SOSCO Pins 2010 Microchip Technology Inc. Clock Source Preliminary DS39957B-page 187 PIC18F87K90 FAMILY FIGURE 13-1: TIMER1 BLOCK DIAGRAM T1GSS<1:0> T1G 00 From Timer2 Match PR2 01 T1GSPM 0 T1G_IN T1GVAL 0 From Comp. 1 Output 10 From Comp. 2 Output 11 Single Pulse TMR1ON T1GPOL D Q CK R Q 1 Acq. Control 1 Q1 Q Data Bus RD T1GCON EN Interrupt T1GGO/T1DONE det T1GTM Set Flag bit TMR1IF on Overflow D Set TMR1GIF TMR1GE TMR1ON TMR1(2) TMR1H EN TMR1L Q D T1CLK Synchronized Clock Input 0 1 TMR1CS<1:0> SOSCO/T1CKI T1OSC SOSCI T1SYNC OUT 1 10 EN 0 SOSCEN (1) FOSC Internal Clock 01 FOSC/4 Internal Clock 00 Synchronize(3) Prescaler 1, 2, 4, 8 det 2 T1CKPS<1:0> FOSC/2 Internal Clock Sleep Input T1CKI Note 1: 2: 3: ST buffer is a high-speed type when using T1CKI. Timer1 register increments on the rising edge. Synchronize does not operate while in Sleep. DS39957B-page 188 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 13.4 Timer1 16-Bit Read/Write Mode TABLE 13-2: Timer1 can be configured for 16-bit reads and writes. When the RD16 control bit (T1CON<1>) is set, the address for TMR1H is mapped to a buffer register for the high byte of Timer1. A read from TMR1L loads the contents of the high byte of Timer1 into the Timer1 High Byte Buffer register. This provides the user with the ability to accurately read all 16 bits of Timer1 without having to determine whether a read of the high byte, followed by a read of the low byte, has become invalid due to a rollover between reads. Oscillator Type Freq. C1 C2 LP 32 kHz 12 pF(1) 12 pF(1) Note 1: Microchip suggests these values as a starting point in validating the oscillator circuit. 2: Higher capacitance increases the stability of the oscillator, but also increases the start-up time. A write to the high byte of Timer1 must also take place through the TMR1H Buffer register. The Timer1 high byte is updated with the contents of TMR1H when a write occurs to TMR1L. This allows a user to write all 16 bits at once to both the high and low bytes of Timer1. 3: Since each resonator/crystal has its own characteristics, the user should consult the resonator/crystal manufacturer for appropriate values of external components. The high byte of Timer1 is not directly readable or writable in this mode. All reads and writes must take place through the Timer1 High Byte Buffer register. Writes to TMR1H do not clear the Timer1 prescaler. The prescaler is only cleared on writes to TMR1L. 13.5 The user must provide a software time delay to ensure proper start-up of the SOSC oscillator. FIGURE 13-2: EXTERNAL COMPONENTS FOR THE SOSC OSCILLATOR C1 12 pF XTAL 32.768 kHz SOSCO C2 12 pF See the Notes with Table 13-2 for additional information about capacitor selection. 2010 Microchip Technology Inc. 5: Incorrect capacitance value may result in a frequency not meeting the crystal manufacturer’s tolerance specification. The SOSC crystal oscillator drive level is determined based on the SOSCSEL (CONFIG1L<4:3>) Configuration bits. The High Drive Level mode, SOSCSEL<1:0> = 11, is intended to drive a wide variety of 32.768 kHz crystals with a variety of load capacitance (CL) ratings. The Low Drive Level mode is highly optimized for extremely low-power consumption. It is not intended to drive all types of 32.768 kHz crystals. In the Low Drive Level mode, the crystal oscillator circuit may not work correctly if excessively large discrete capacitors are placed on the SOSCO and SOSCI pins. This mode is designed to work only with discrete capacitances of approximately 3 pF-10 pF on each pin. Crystal manufacturers usually specify a CL (load capacitance) rating for their crystals. This value is related to, but not necessarily the same as, the values that should be used for C1 and C2 in Figure 13-2. PIC18F87K90 SOSCI Note: 4: Capacitor values are for design guidance only. Values listed would be typical of a CL = 10 pF rated crystal, when SOSCSEL = 11. SOSC Oscillator An on-chip crystal oscillator circuit is incorporated between pins, SOSCI (input) and SOSCO (amplifier output). It is enabled by setting one of five bits: any of the four SOSCEN bits in the TxCON registers (TxCON<3>) or the SOSCGO bit in the OSCCON2 register (OSCCON2<3>). The oscillator is a low-power circuit rated for 32 kHz crystals. It will continue to run during all power-managed modes. The circuit for a typical LP oscillator is depicted in Figure 13-2. Table 13-2 provides the capacitor selection for the SOSC oscillator. CAPACITOR SELECTION FOR THE TIMER OSCILLATOR(2,3,4,5) For more details on selecting the optimum C1 and C2 for a given crystal, see the crystal manufacture’s applications information. The optimum value depends in part on the amount of parasitic capacitance in the circuit, which is often unknown. For that reason, it is highly recommended that thorough testing and validation of the oscillator be performed after values have been selected. Preliminary DS39957B-page 189 PIC18F87K90 FAMILY 13.5.1 USING SOSC AS A CLOCK SOURCE FIGURE 13-3: The SOSC oscillator is also available as a clock source in power-managed modes. By setting the clock select bits, SCS<1:0> (OSCCON<1:0>), to ‘01’, the device switches to SEC_RUN mode and both the CPU and peripherals are clocked from the SOSC oscillator. If the IDLEN bit (OSCCON<7>) are cleared and a SLEEP instruction is executed, the device enters SEC_IDLE mode. Additional details are available in Section 4.0 “Power-Managed Modes”. OSCILLATOR CIRCUIT WITH GROUNDED GUARD RING VDD VSS OSC1 OSC2 Whenever the SOSC oscillator is providing the clock source, the SOSC System Clock Status Flag, SOSCRUN (OSCCON2<6>), is set. This can be used to determine the controller’s current clocking mode. It can also indicate the clock source currently being used by the Fail-Safe Clock Monitor. If the Clock Monitor is enabled and the SOSC oscillator fails while providing the clock, polling the SOCSRUN bit will indicate whether the clock is being provided by the SOSC oscillator or another source. 13.5.2 SOSC OSCILLATOR LAYOUT CONSIDERATIONS The SOSC oscillator circuit draws very little power during operation. Due to the low-power nature of the oscillator, it may also be sensitive to rapidly changing signals in close proximity. This is especially true when the oscillator is configured for extremely low-power mode (CONFIG1L<4:3> (SOSCSEL) = 01). The oscillator circuit, displayed in Figure 13-2, should be located as close as possible to the microcontroller. There should be no circuits passing within the oscillator circuit boundaries other than VSS or VDD. If a high-speed circuit must be located near the oscillator, it may help to have a grounded guard ring around the oscillator circuit. The guard, as displayed in Figure 13-3, could be used on a single-sided PCB or in addition to a ground plane. (Examples of a high-speed circuit include the ECCP1 pin, in Output Compare or PWM mode, or the primary oscillator, using the OSC2 pin.) DS39957B-page 190 RC0 RC1 RC2 Note: Not drawn to scale. In the Low Drive Level mode, SOSCSEL<1:0> = 01, it is critical that RC2 I/O pin signals be kept away from the oscillator circuit. Configuring RC2 as a digital output, and toggling it, can potentially disturb the oscillator circuit, even with a relatively good PCB layout. If possible, either leave RC2 unused or use it as an input pin with a slew rate limited signal source. If RC2 must be used as a digital output, it may be necessary to use the High Drive Level Oscillator mode (SOSCSEL<1:0> = 11) with many PCB layouts. Even in the High Drive Level mode, careful layout procedures should still be followed when designing the oscillator circuit. In addition to dV/dt induced noise considerations, it is important to ensure that the circuit board is clean. Even a very small amount of conductive soldering flux residue can cause PCB leakage currents that can overwhelm the oscillator circuit. 13.6 Timer1 Interrupt The TMR1 register pair (TMR1H:TMR1L) increments from 0000h to FFFFh and rolls over to 0000h. The Timer1 interrupt, if enabled, is generated on overflow which is latched in interrupt flag bit, TMR1IF (PIR1<0>). This interrupt can be enabled or disabled by setting or clearing the Timer1 Interrupt Enable bit, TMR1IE (PIE1<0>). Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 13.7 Resetting Timer1 Using the ECCP Special Event Trigger If ECCP modules are configured to use Timer1 and to generate a Special Event Trigger in Compare mode (CCPxM<3:0> = 1011), this signal will reset Timer1. The trigger from ECCP2 will also start an A/D conversion, if the A/D module is enabled. (For more information, see Section 19.3.4 “Special Event Trigger”.) To take advantage of this feature, the module must be configured as either a timer or a synchronous counter. When used this way, the CCPRxH:CCPRxL register pair effectively becomes a period register for Timer1. If Timer1 is running in Asynchronous Counter mode, this Reset operation may not work. 13.8.1 The Timer1 Gate Enable mode is enabled by setting the TMR1GE bit of the T1GCON register. The polarity of the Timer1 Gate Enable mode is configured using the T1GPOL bit (T1GCON<6>). When Timer1 Gate Enable mode is enabled, Timer1 will increment on the rising edge of the Timer1 clock source. When Timer1 Gate Enable mode is disabled, no incrementing will occur and Timer1 will hold the current count. See Figure 13-4 for timing details. TABLE 13-3: T1CLK(†) In the event that a write to Timer1 coincides with a Special Event Trigger, the write operation will take precedence. Note: 13.8 The Special Event Trigger from the ECCPx module will only clear the TMR1 register’s content, but not set the TMR1IF interrupt flag bit (PIR1<0>). Timer1 Gate TIMER1 GATE ENABLE SELECTIONS T1GPOL T1G Pin (T1GCON<6>) Timer1 Operation 0 0 Counts 0 1 Holds Count 1 0 Holds Count 1 1 Counts † The clock on which TMR1 is running. For more information, see Figure 13-1. Note: Timer1 can be configured to count freely or the count can be enabled and disabled using the Timer1 gate circuitry. This is also referred to as Timer1 gate count enable. Timer1 gate can also be driven by multiple selectable sources. 2010 Microchip Technology Inc. TIMER1 GATE COUNT ENABLE Preliminary The CCP and ECCP modules use Timers, 1 through 8, for some modes. The assignment of a particular timer to a CCP/ECCP module is determined by the Timer to CCP enable bits in the CCPTMRSx registers. For more details, see Register 19-2, Register 18-2 and Register 18-3. DS39957B-page 191 PIC18F87K90 FAMILY FIGURE 13-4: TIMER1 GATE COUNT ENABLE MODE TMR1GE T1GPOL T1G_IN T1CKI T1GVAL Timer1 13.8.2 N N+1 13.8.2.2 TIMER1 GATE SOURCE SELECTION The Timer1 gate source can be selected from one of four sources. Source selection is controlled by the T1GSSx bits, T1GCON<1:0> (see Table 13-4). TABLE 13-4: TIMER1 GATE SOURCES T1GSS<1:0> Timer1 Gate Source 00 Timer1 Gate Pin 01 TMR2 to Match PR2 (TMR2 increments to match PR2) 10 Comparator 1 Output (Comparator logic high output) 11 Comparator 2 Output (Comparator logic high output) N+4 Timer2 Match Gate Operation The TMR2 register will increment until it matches the value in the PR2 register. On the very next increment cycle, TMR2 will be reset to 00h. When this Reset occurs, a low-to-high pulse will automatically be generated and internally supplied to the Timer1 gate circuitry. The pulse will remain high for one instruction cycle and will return back to a low state until the next match. 13.8.2.3 T1G Pin Gate Operation The T1G pin is one source for Timer1 gate control. It can be used to supply an external source to the Timer1 gate circuitry. DS39957B-page 192 N+3 Depending on T1GPOL, Timer1 increments differently when TMR2 matches PR2. When T1GPOL = 1, Timer1 increments for a single instruction cycle following a TMR2 match with PR2. When T1GPOL = 0, Timer1 increments continuously, except for the cycle following the match, when the gate signal goes from low-to-high. The polarity for each available source is also selectable, controlled by the T1GPOL bit (T1GCON<6>). 13.8.2.1 N+2 Comparator 1 Output Gate Operation The output of Comparator 1 can be internally supplied to the Timer1 gate circuitry. After setting up Comparator 1 with the CM1CON register, Timer1 will increment depending on the transition of the CMP1OUT (CMSTAT<5>) bit. 13.8.2.4 Comparator 2 Output Gate Operation The output of Comparator 2 can be internally supplied to the Timer1 gate circuitry. After setting up Comparator 2 with the CM2CON register, Timer1 will increment depending on the transition of the CMP2OUT (CMSTAT<6>) bit. Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 13.8.3 TIMER1 GATE TOGGLE MODE When Timer1 Gate Toggle mode is enabled, it is possible to measure the full cycle length of a Timer1 gate signal, as opposed to the duration of a single level pulse. The Timer1 gate source is routed through a flip-flop that changes state on every incrementing edge of the signal. (For timing details, see Figure 13-5.) FIGURE 13-5: The T1GVAL bit (T1GCON<2>) indicates when the Toggled mode is active and the timer is counting. The Timer1 Gate Toggle mode is enabled by setting the T1GTM bit (T1GCON<5>). When T1GTM is cleared, the flip-flop is cleared and held clear. This is necessary in order to control which edge is measured. TIMER1 GATE TOGGLE MODE TMR1GE T1GPOL T1GTM T1G_IN T1CKI T1GVAL Timer1 N 2010 Microchip Technology Inc. N+1 N+2 N+3 N+4 Preliminary N+5 N+6 N+7 N+8 DS39957B-page 193 PIC18F87K90 FAMILY 13.8.4 TIMER1 GATE SINGLE PULSE MODE When Timer1 Gate Single Pulse mode is enabled, it is possible to capture a single pulse gate event. Timer1 Gate Single Pulse mode is enabled by setting the T1GSPM bit (T1GCON<4>) and the T1GGO/T1DONE bit (T1GCON<3>). The Timer1 will be fully enabled on the next incrementing edge. On the next trailing edge of the pulse, the T1GGO/ T1DONE bit will automatically be cleared. No other gate events will be allowed to increment Timer1 until the T1GGO/T1DONE bit is once again set in software. FIGURE 13-6: Clearing the T1GSPM bit of the T1GCON register will also clear the T1GGO/T1DONE bit. (For timing details, see Figure 13-6.) Simultaneously enabling the Toggle and Single Pulse modes will permit both sections to work together. This allows the cycle times on the Timer1 gate source to be measured. (For timing details, see Figure 13-7.) 13.8.5 TIMER1 GATE VALUE STATUS When the Timer1 gate value status is utilized, it is possible to read the most current level of the gate control value. The value is stored in the T1GVAL bit (T1GCON<2>). This bit is valid even when the Timer1 gate is not enabled (TMR1GE bit is cleared). TIMER1 GATE SINGLE PULSE MODE TMR1GE T1GPOL T1GSPM T1GGO/ Cleared by Hardware on Falling Edge of T1GVAL Set by Software T1DONE Counting Enabled on Rising Edge of T1G T1G_IN T1CKI T1GVAL Timer1 RTCCIF DS39957B-page 194 N N+1 N+2 Set by Hardware on Falling Edge of T1GVAL Cleared by Software Preliminary Cleared by Software 2010 Microchip Technology Inc. PIC18F87K90 FAMILY FIGURE 13-7: TIMER1 GATE SINGLE PULSE AND TOGGLE COMBINED MODE TMR1GE T1GPOL T1GSPM T1GTM T1GGO/ Cleared by Hardware on Falling Edge of T1GVAL Set by Software T1DONE Counting Enabled on Rising Edge of T1G T1G_IN T1CKI T1GVAL Timer1 TABLE 13-5: Name N+4 N+3 Set by Hardware on Falling Edge of T1GVAL Cleared by Software RTCCIF N+2 N+1 N Cleared by Software REGISTERS ASSOCIATED WITH TIMER1 AS A TIMER/COUNTER Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Reset Values on Page: TMR0IE INT0IE RBIE TMR0IF INT0IF RBIF 73 PIR1 — ADIF RC1IF TX1IF SSP1IF TMR1GIF TMR2IF TMR1IF 75 PIE1 — ADIE RC1IE TX1IE SSP1IE TMR1GIE TMR2IE TMR1IE 75 IPR1 — ADIP RC1IP TX1IP SSP1IP TMR1GIP TMR2IP TMR1IP 75 INTCON GIE/GIEH PEIE/GIEL TMR1L Timer1 Register Low Byte 74 TMR1H Timer1 Register High Byte 74 T1CON TMR1CS1 TMR1CS0 T1CKPS1 T1CKPS0 SOSCEN T1SYNC RD16 TMR1ON 74 T1GCON TMR1GE T1GPOL T1GTM T1GSPM T1GGO/ T1DONE T1GVAL T1GSS1 T1GSS0 75 — SOSCRUN — — SOSCGO — MFIOFS MFIOSEL 77 CCPTMRS0 C3TSEL1 C3TSEL0 C2TSEL2 C2TSEL1 C2TSEL0 C1TSEL2 C1TSEL1 C1TSEL0 79 OSCCON2 CCPTMRS1 C7TSEL1 C7TSEL0 CCPTMRS2 — — — C6TSEL0 — C5TSEL0 C4TSEL1 C4TSEL0 79 — C10TSEL0 — C9TSEL0 C8TSEL1 C8TSEL0 79 Legend: Shaded cells are not used by the Timer1 module. 2010 Microchip Technology Inc. Preliminary DS39957B-page 195 PIC18F87K90 FAMILY NOTES: DS39957B-page 196 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 14.0 TIMER2 MODULE The Timer2 module incorporates the following features: • 8-bit Timer and Period registers (TMR2 and PR2, respectively) • Both registers readable and writable • Software programmable prescaler (1:1, 1:4 and 1:16) • Software programmable postscaler (1:1 through 1:16) • Interrupt on TMR2 to PR2 match • Optional use as the shift clock for the MSSP modules The module is controlled through the T2CON register (Register 14-1) that enables or disables the timer, and configures the prescaler and postscaler. Timer2 can be shut off by clearing control bit, TMR2ON (T2CON<2>), to minimize power consumption. The value of TMR2 is compared to that of the Period register, PR2, on each clock cycle. When the two values match, the comparator generates a match signal as the timer output. This signal also resets the value of TMR2 to 00h on the next cycle and drives the output counter/ postscaler. (See Section 14.2 “Timer2 Interrupt”.) The TMR2 and PR2 registers are both directly readable and writable. The TMR2 register is cleared on any device Reset, while the PR2 register initializes at FFh. Both the prescaler and postscaler counters are cleared on the following events: • A write to the TMR2 register • A write to the T2CON register • Any device Reset (Power-on Reset (POR), MCLR Reset, Watchdog Timer Reset (WDTR) or Brown-out Reset [BOR]) TMR2 is not cleared when T2CON is written. Note: A simplified block diagram of the module is shown in Figure 14-1. 14.1 Timer2 Operation In normal operation, TMR2 is incremented from 00h on each clock (FOSC/4). A 4-bit counter/prescaler on the clock input gives the prescale options of direct input, divide-by-4 or divide-by-16. These are selected by the prescaler control bits, T2CKPS<1:0> (T2CON<1:0>). REGISTER 14-1: The CCP and ECCP modules use Timers 1 through 8 for some modes. The assignment of a particular timer to a CCP/ECCP module is determined by the Timer to CCP enable bits in the CCPTMRSx registers. For more details, see Register 19-2, Register 18-2 and Register 18-3. T2CON: TIMER2 CONTROL REGISTER U-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 — T2OUTPS3 T2OUTPS2 T2OUTPS1 T2OUTPS0 TMR2ON T2CKPS1 T2CKPS0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7 Unimplemented: Read as ‘0’ bit 6-3 T2OUTPS<3:0>: Timer2 Output Postscale Select bits 0000 = 1:1 Postscale 0001 = 1:2 Postscale • • • 1111 = 1:16 Postscale bit 2 TMR2ON: Timer2 On bit 1 = Timer2 is on 0 = Timer2 is off bit 1-0 T2CKPS<1:0>: Timer2 Clock Prescale Select bits 00 = Prescaler is 1 01 = Prescaler is 4 1x = Prescaler is 16 2010 Microchip Technology Inc. Preliminary x = Bit is unknown DS39957B-page 197 PIC18F87K90 FAMILY 14.2 Timer2 Interrupt 14.3 Timer2 can also generate an optional device interrupt. The Timer2 output signal (TMR2 to PR2 match) provides the input for the 4-bit output counter/postscaler. This counter generates the TMR2 match interrupt flag, which is latched in TMR2IF (PIR1<1>). The interrupt is enabled by setting the TMR2 Match Interrupt Enable bit, TMR2IE (PIE1<1>). Timer2 Output The unscaled output of TMR2 is available primarily to the ECCP modules, where it is used as a time base for operations in PWM mode. Timer2 can optionally be used as the shift clock source for the MSSP modules operating in SPI mode. Additional information is provided in Section 21.0 “Master Synchronous Serial Port (MSSP) Module”. A range of 16 postscaler options (from 1:1 through 1:16 inclusive) can be selected with the postscaler control bits, T2OUTPS<3:0> (T2CON<6:3>). FIGURE 14-1: TIMER2 BLOCK DIAGRAM 4 T2OUTPS<3:0> 1:1 to 1:16 Postscaler 2 T2CKPS<1:0> TMR2 PR2 Comparator 8 8 8 Internal Data Bus Name TMR2 Output (to PWM or MSSPx) TMR2/PR2 Match Reset 1:1, 1:4, 1:16 Prescaler FOSC/4 TABLE 14-1: Set TMR2IF REGISTERS ASSOCIATED WITH TIMER2 AS A TIMER/COUNTER Bit 7 Bit 6 INTCON GIE/GIEH PEIE/GIEL Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Reset Values on Page: 73 TMR0IE INT0IE RBIE TMR0IF INT0IF RBIF PIR1 — ADIF RC1IF TX1IF SSP1IF TMR1GIF TMR2IF TMR1IF 75 PIE1 — ADIE RC1IE TX1IE SSP1IE TMR1GIE TMR2IE TMR1IE 75 IPR1 — ADIP RC1IP TX1IP SSP1IP TMR1GIP TMR2IP TMR1IP 75 TMR2 T2CON PR2 Timer2 Register — 74 T2OUTPS3 T2OUTPS2 T2OUTPS1 T2OUTPS0 TMR2ON T2CKPS1 T2CKPS0 Timer2 Period Register 74 74 Legend: — = unimplemented, read as ‘0’. Shaded cells are not used by the Timer2 module. DS39957B-page 198 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 15.0 TIMER3/5/7 MODULES The Timer3/5/7 timer/counter modules incorporate these features: • Software-selectable operation as a 16-bit timer or counter • Readable and writable 8-bit registers (TMRxH and TMRxL) • Selectable clock source (internal or external) with device clock or SOSC oscillator internal options • Interrupt-on-overflow • Module Reset on ECCP Special Event Trigger A simplified block diagram of the Timer3/5/7 module is shown in Figure 15-1. The Timer3/5/7 module is controlled through the TxCON register (Register 15-1). It also selects the clock source options for the ECCP modules. (For more information, see Section 19.1.1 “ECCP Module and Timer Resources”.) The FOSC clock source should not be used with the ECCP capture/compare features. If the timer will be used with the capture or compare features, always select one of the other timer clocking options. Timer7 is unimplemented for devices with program memory of 32 Kbytes (PIC18FX5K90). Note: Throughout this section, generic references are used for register and bit names that are the same, except for an ‘x’ variable that indicates the item’s association with the Timer3, Timer5 or Timer7 module. For example, the control register is named TxCON and refers to T3CON, T5CON and T7CON. 2010 Microchip Technology Inc. Preliminary DS39957B-page 199 PIC18F87K90 FAMILY REGISTER 15-1: TxCON: TIMERx CONTROL REGISTER R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 TMRxCS1 TMRxCS0 TxCKPS1 TxCKPS0 SOSCEN TxSYNC RD16 TMRxON bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7-6 TMRxCS<1:0>: Timerx Clock Source Select bits 10 = The Timer1 clock source is either a pin or an oscillator depending on the SOSCEN bit. SOSCEN = 0: External clock is from the T1CKI pin (on the rising edge). SOSCEN = 1: Crystal oscillator is on the SOSCI/SOSCO pins. 01 = Timerx clock source is the system clock (FOSC)(1) 00 = Timerx clock source is the instruction clock (FOSC/4) bit 5-4 TxCKPS<1:0>: Timerx Input Clock Prescale Select bits 11 = 1:8 Prescale value 10 = 1:4 Prescale value 01 = 1:2 Prescale value 00 = 1:1 Prescale value bit 3 SOSCEN: SOSC Oscillator Enable bit 1 = SOSC is enabled for Timerx (based on SOSCSEL fuses) 0 = SOSC is disabled for Timerx bit 2 TxSYNC: Timerx External Clock Input Synchronization Control bit (Not usable if the device clock comes from Timer1/Timer3.) When TMRxCS<1:0> = 10: 1 = Do not synchronize external clock input 0 = Synchronize external clock input When TMRxCS<1:0> = 0x: This bit is ignored; Timer3 uses the internal clock. bit 1 RD16: 16-Bit Read/Write Mode Enable bit 1 = Enables register read/write of Timerx in one 16-bit operation 0 = Enables register read/write of Timerx in two 8-bit operations bit 0 TMRxON: Timerx On bit 1 = Enables Timerx 0 = Stops Timerx Note 1: The FOSC clock source should not be selected if the timer will be used with the ECCP capture/compare features. DS39957B-page 200 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 15.1 Timer3/5/7 Gate Control Register The Timer3/5/7 Gate Control register (TxGCON), provided in Register 14-2, is used to control the Timerx gate. REGISTER 15-2: TxGCON: TIMERx GATE CONTROL REGISTER(1) R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R-x R/W-0 R/W-0 TMRxGE TxGPOL TxGTM TxGSPM TxGGO/TxDONE TxGVAL TxGSS1 TxGSS0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 TMRxGE: Timerx Gate Enable bit If TMRxON = 0: This bit is ignored. If TMRxON = 1: 1 = Timerx counting is controlled by the Timerx gate function 0 = Timerx counts regardless of the Timerx gate function bit 6 TxGPOL: Timerx Gate Polarity bit 1 = Timerx gate is active-high (Timerx counts when gate is high) 0 = Timerx gate is active-low (Timerx counts when gate is low) bit 5 TxGTM: Timerx Gate Toggle Mode bit 1 = Timerx Gate Toggle mode is enabled. 0 = Timerx Gate Toggle mode is disabled and toggle flip-flop is cleared Timerx gate flip-flop toggles on every rising edge. bit 4 TxGSPM: Timerx Gate Single Pulse Mode bit 1 = Timerx Gate Single Pulse mode is enabled and is controlling the Timerx gate 0 = Timerx Gate Single Pulse mode is disabled bit 3 TxGGO/TxDONE: Timerx Gate Single Pulse Acquisition Status bit 1 = Timerx gate single pulse acquisition is ready, waiting for an edge 0 = Timerx gate single pulse acquisition has completed or has not been started This bit is automatically cleared when TxGSPM is cleared. bit 2 TxGVAL: Timerx Gate Current State bit Indicates the current state of the Timerx gate that could be provided to TMRxH:TMRxL. Unaffected by the Timerx Gate Enable (TMRxGE) bit. bit 1-0 TxGSS<1:0>: Timerx Gate Source Select bits 11 = Comparator 2 output 10 = Comparator 1 output 01 = TMR(x + 1) to match PR(x + 1) output(2) 00 = Timer1 gate pin Watchdog Timer oscillator is turned on if TMRxGE = 1, regardless of the state of TMRxON. Note 1: 2: Programming the TxGCON prior to TxCON is recommended. Timer(x+1) will be Timer4/6/8 or Timerx Timer3/5/7, respectively. 2010 Microchip Technology Inc. Preliminary DS39957B-page 201 PIC18F87K90 FAMILY REGISTER 15-3: OSCCON2: OSCILLATOR CONTROL REGISTER 2 U-0 R-0 U-0 U-0 R/W-0 U-0 R-x R/W-0 — SOSCRUN — — SOSCGO — MFIOFS MFIOSEL bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 Unimplemented: Read as ‘0’ bit 6 SOSCRUN: SOSC Run Status bit 1 = System clock comes from a secondary SOSC 0 = System clock comes from an oscillator other than SOSC bit 5-4 Unimplemented: Read as ‘0’ bit 3 SOSCGO: Oscillator Start Control bit 1 = Oscillator is running, even if no other sources are requesting it 0 = Oscillator is shut off if no other sources are requesting it (When the SOSC is selected to run from a digital clock input, rather than an external crystal, this bit has no effect.) bit 2 Unimplemented: Read as ‘0’ bit 1 MFIOFS: MF-INTOSC Frequency Stable bit 1 = MF-INTOSC is stable 0 = MF-INTOSC is not stable bit 0 MFIOSEL: MF-INTOSC Select bit 1 = MF-INTOSC is used in place of HF-INTOSC frequencies of 500 kHz, 250 kHz and 31.25 kHz 0 = MF-INTOSC is not used DS39957B-page 202 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 15.2 Timer3/5/7 Operation The operating mode is determined by the clock select bits, TMRxCSx (TxCON<7:6>). When the TMRxCSx bits are cleared (= 00), Timer3/5/7 increments on every internal instruction cycle (FOSC/4). When TMRxCSx = 01, the Timer3/5/7 clock source is the system clock (FOSC), and when it is ‘10’, Timer3/5/7 works as a counter from the external clock from the TxCKI pin (on the rising edge after the first falling edge) or the SOSC oscillator. Timer3, Timer5 and Timer7 can operate in these modes: • • • • Timer Synchronous Counter Asynchronous Counter Timer with Gated Control FIGURE 15-1: TIMER3/5/7 BLOCK DIAGRAM TxGSS<1:0> TxG 00 From TMR(x + 1) Match PR(x + 1) 01 From Comp. 1 Output 10 From Comp. 2 Output 11 TxGSPM 0 TxG_IN TxGVAL 0 Single Pulse TMRxON TxGPOL D Q CK R Q 1 Acq. Control 1 Q1 Data Bus D Q RD T3GCON EN Interrupt TxGGO/TxDONE Set TMRxGIF det TxGTM TMRxGE Set Flag bit TMRxIF on Overflow TMRxON TMRx(2) TMRxH EN TMRxL Q D TxCLK Synchronized Clock Input 0 1 TMRxCS<1:0> SOSCO TxOSC SOSCI TxSYNC OUT Prescaler 1, 2, 4, 8 1 10 EN 0 SOSCEN (1) FOSC Internal Clock 01 FOSC/4 Internal Clock 00 Synchronize(3) det 2 TxCKPS<1:0> FOSC/2 Internal Clock Sleep Input TxCKI Note 1: 2: 3: ST Buffer is high-speed type when using TxCKI. Timerx registers increment on rising edge. Synchronize does not operate while in Sleep. 2010 Microchip Technology Inc. Preliminary DS39957B-page 203 PIC18F87K90 FAMILY 15.3 Timer3/5/7 16-Bit Read/Write Mode also be set. As previously noted, this also configures Timer3/5/7 to increment on every rising edge of the oscillator source. Timer3/5/7 can be configured for 16-bit reads and writes (see Figure 15.3). When the RD16 control bit (TxCON<1>) is set, the address for TMRxH is mapped to a buffer register for the high byte of Timer3/5/7. A read from TMRxL will load the contents of the high byte of Timer3/5/7 into the Timerx High Byte Buffer register. This provides users with the ability to accurately read all 16 bits of Timer3/5/7 without having to determine whether a read of the high byte, followed by a read of the low byte, has become invalid due to a rollover between reads. 15.5 A write to the high byte of Timer3/5/7 must also take place through the TMRxH Buffer register. The Timer3/ 5/7 high byte is updated with the contents of TMRxH when a write occurs to TMRxL. This allows users to write all 16 bits to both the high and low bytes of Timer3/5/7 at once. 15.5.1 The SOSC oscillator is described in Section 13.0 “Timer1 Module”. Timer3/5/7 can be configured to count freely or the count can be enabled and disabled using the Timer3/ 5/7 gate circuitry. This is also referred to as the Timer3/5/7 gate count enable. The Timer3/5/7 gate can also be driven by multiple selectable sources. When Timerx Gate Enable mode is enabled, Timer3/5/ 7 will increment on the rising edge of the Timer3/5/7 clock source. When Timerx Gate Enable mode is disabled, no incrementing will occur and Timer3/5/7 will hold the current count. See Figure 15-2 for timing details. Writes to TMRxH do not clear the Timer3/5/7 prescaler. The prescaler is only cleared on writes to TMRxL. Using the SOSC Oscillator as the Timer3/5/7 Clock Source TABLE 15-1: The SOSC internal oscillator may be used as the clock source for Timer3/5/7. The SOSC oscillator is enabled by setting one of five bits: any of the four SOSCEN bits in the TxCON registers (TxCON<3>) or the SOSCGO bit in the OSCCON2 register (OSCCON2<3>). To use it as the Timer3/5/7 clock source, the TMRxCS bit must FIGURE 15-2: TIMER3/5/7 GATE COUNT ENABLE The Timerx Gate Enable mode is enabled by setting the TMRxGE bit (TxGCON<7>). The polarity of the Timerx Gate Enable mode is configured using the TxGPOL bit (TxGCON<6>). The high byte of Timer3/5/7 is not directly readable or writable in this mode. All reads and writes must take place through the Timerx High Byte Buffer register. 15.4 Timer3/5/7 Gates TIMER3/5/7 GATE ENABLE SELECTIONS TxCLK(†) TxGPOL (TxGCON<6>) TxG Pin 0 0 Counts 0 1 Holds Count Timerx Operation TIMER3/5/7 GATE COUNT ENABLE MODE TMRxGE TxGPOL TxG_IN TxCKI TxGVAL Timer3/5/7 DS39957B-page 204 N N+1 Preliminary N+2 N+3 N+4 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 15.5.2 TIMER3/5/7 GATE SOURCE SELECTION The Timer3/5/7 gate source can be selected from one of four different sources. Source selection is controlled by the TxGSS<1:0> bits (TxGCON<1:0>). The polarity for each available source is also selectable and is controlled by the TxGPOL bit (TxGCON <6>). TABLE 15-2: TIMER3/5/7 GATE SOURCES TxGSS<1:0> Timerx Gate Source 00 Timerx Gate Pin 01 TMR(x + 1) to Match PR(x + 1) (TMR(x + 1) increments to match PR(x + 1) 10 Comparator 1 Output (Comparator logic high output) 11 Comparator 2 Output (Comparator logic high output) 15.5.2.1 Comparator 1 Output Gate Operation The output of Comparator 1 can be internally supplied to the Timerx gate circuitry. After setting up Comparator 1 with the CM1CON register, Timerx will increment depending on the transitions of the CMP1OUT (CMSTAT<5>) bit. Comparator 2 Output Gate Operation The output of Comparator 2 can be internally supplied to the Timerx gate circuitry. After setting up Comparator 2 with the CM2CON register, Timerx will increment depending on the transitions of the CMP2OUT (CMSTAT<6>) bit. TxG Pin Gate Operation Timer4/6/8 Match Gate Operation The Timer4/6/8 register will increment until it matches the value in the PRx register. On the very next increment cycle, TMRx will be reset to 00h. When this Reset occurs, a low-to-high pulse will automatically be generated and internally supplied to the Timerx gate circuitry. The pulse will remain high for one instruction cycle and will return back to a low state until the next match. FIGURE 15-3: 15.5.2.3 15.5.2.4 The TxG pin is one source for Timer3/5/7 gate control. It can be used to supply an external source to the Timerx gate circuitry. 15.5.2.2 Depending on TxGPOL, Timerx increments differently when TMR(x + 1) matches PR(x + 1). When TxGPOL = 1, Timerx increments for a single instruction cycle following a TMR(x + 1) match with PR(x + 1). When TxGPOL = 0, Timerx increments continuously except for the cycle following the match when the gate signal goes from low-to-high. 15.5.3 TIMER3/5/7 GATE TOGGLE MODE When Timer3/5/7 Gate Toggle mode is enabled, it is possible to measure the full cycle length of a Timer3/5/ 7 gate signal, as opposed to the duration of a single level pulse. The Timerx gate source is routed through a flip-flop that changes state on every incrementing edge of the signal. (For timing details, see Figure 15-3.) The TxGVAL bit will indicate when the Toggled mode is active and the timer is counting. Timer3/5/7 Gate Toggle mode is enabled by setting the TxGTM bit (TxGCON<5>). When the TxGTM bit is cleared, the flip-flop is cleared and held clear. This is necessary in order to control which edge is measured. TIMER3/5/7 GATE TOGGLE MODE TMRxGE TxGPOL TxGTM TxG_IN TxCKI TxGVAL Timer3/5/7 N 2010 Microchip Technology Inc. N+1 N+2 N+3 N+4 Preliminary N+5 N+6 N+7 N+8 DS39957B-page 205 PIC18F87K90 FAMILY 15.5.4 TIMER3/5/7 GATE SINGLE PULSE MODE No other gate events will be allowed to increment Timer3/5/7 until the TxGGO/TxDONE bit is once again set in software. When Timer3/5/7 Gate Single Pulse mode is enabled, it is possible to capture a single pulse gate event. Timer3/5/7 Gate Single Pulse mode is first enabled by setting the TxGSPM bit (TxGCON<4>). Next, the TxGGO/TxDONE bit (TxGCON<3>) must be set. Clearing the TxGSPM bit also will clear the TxGGO/ TxDONE bit. (For timing details, see Figure 15-4.) Simultaneously enabling the Toggle mode and the Single Pulse mode will permit both sections to work together. This allows the cycle times on the Timer3/5/7 gate source to be measured. (For timing details, see Figure 15-5.) The Timer3/5/7 will be fully enabled on the next incrementing edge. On the next trailing edge of the pulse, the TxGGO/TxDONE bit will automatically be cleared. FIGURE 15-4: TIMER3/5/7 GATE SINGLE PULSE MODE TMRxGE TxGPOL TxGSPM TxGGO/ Cleared by Hardware on Falling Edge of TxGVAL Set by Software TxDONE Counting Enabled on Rising Edge of TxG TxG_IN T1CKI TxGVAL Timer3/5/7 TMRxGIF DS39957B-page 206 N N+1 N+2 Set by Hardware on Falling Edge of TxGVAL Cleared by Software Preliminary Cleared by Software 2010 Microchip Technology Inc. PIC18F87K90 FAMILY FIGURE 15-5: TIMER3/5/7 GATE SINGLE PULSE AND TOGGLE COMBINED MODE TMRxGE TxGPOL TxGSPM TxGTM Cleared by Hardware on Falling Edge of TxGVAL Set by Software TxGGO/ TxDONE Counting Enabled on Rising Edge of TxG TxG_IN TxCKI TxGVAL Timer3/5/7 TMRxGIF 15.5.5 N N+1 N+2 N+3 Set by Hardware on Falling Edge of TxGVAL Cleared by Software TIMER3/5/7 GATE VALUE STATUS When Timer3/5/7 gate value status is utilized, it is possible to read the most current level of the gate control value. The value is stored in the TxGVAL bit (TxGCON<2>). The TxGVAL bit is valid even when the Timer3/5/7 gate is not enabled (TMRxGE bit is cleared). 15.5.6 N+4 Cleared by Software TIMER3/5/7 GATE EVENT INTERRUPT When the Timer3/5/7 gate event interrupt is enabled, it is possible to generate an interrupt upon the completion of a gate event. When the falling edge of TxGVAL occurs, the TMRxGIF flag bit in the PIRx register will be set. If the TMRxGIE bit in the PIEx register is set, then an interrupt will be recognized. The TMRxGIF flag bit operates even when the Timer3/ 5/7 gate is not enabled (TMRxGE bit is cleared). 2010 Microchip Technology Inc. Preliminary DS39957B-page 207 PIC18F87K90 FAMILY 15.6 Timer3/5/7 Interrupt 15.7 The TMRx register pair (TMRxH:TMRxL) increments from 0000h to FFFFh and overflows to 0000h. The Timerx interrupt, if enabled, is generated on overflow and is latched in the interrupt flag bit, TMRxIF. Table 15-3 gives each module’s flag bit. TABLE 15-3: TIMER3/5/7 INTERRUPT FLAG BITS Timer Module Flag Bit 3 PIR2<1> 5 PIR5<1> 7 PIR5<3> TIMER3/5/7 INTERRUPT ENABLE BITS Timer Module Flag Bit 3 PIE2<1> 5 PIE5<1> 7 PIE5<3> DS39957B-page 208 If the ECCP modules are configured to use Timerx and to generate a Special Event Trigger in Compare mode (CCPxM<3:0> = 1011), this signal will reset Timerx. The trigger from ECCP2 will also start an A/D conversion if the A/D module is enabled (For more information, see Section 19.3.4 “Special Event Trigger”.) The module must be configured as either a timer or synchronous counter to take advantage of this feature. When used this way, the CCPRxH:CCPRxL register pair effectively becomes a Period register for Timerx. This interrupt can be enabled or disabled by setting or clearing the TMRxIE bit, respectively. Table 15-4 gives each module’s enable bit. TABLE 15-4: Resetting Timer3/5/7 Using the ECCP Special Event Trigger If Timerx is running in Asynchronous Counter mode, the Reset operation may not work. In the event that a write to Timerx coincides with a Special Event Trigger from an ECCP module, the write will take precedence. Note: The Special Event Triggers from the ECCPx module will only clear the TMR3 register’s content, but not set the TMR3IF interrupt flag bit (PIR1<0>). Note: The CCP and ECCP modules use Timers, 1 through 8, for some modes. The assignment of a particular timer to a CCP/ECCP module is determined by the Timer to CCP enable bits in the CCPTMRSx registers. For more details, see Register 19-2, Register 18-2 and Register 18-3. Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY TABLE 15-5: Name INTCON REGISTERS ASSOCIATED WITH TIMER3/5/7 AS A TIMER/COUNTER Bit 7 Bit 6 Bit 5 GIE/GIEH PEIE/GIEL TMR0IE Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Reset Values on Page: 73 INT0IE RBIE TMR0IF INT0IF RBIF PIR5 TMR7GIF(1) TMR12IF(1) TMR10IF(1) TMR8IF TMR7IF(1) TMR6IF TMR5IF TMR4IF 75 PIE5 TMR7GIE(1) TMR12IE(1) TMR10IE(1) TMR8IE TMR7IE(1) TMR6IE TMR5IE TMR4IE 75 PIR2 OSCFIF — SSP2IF BCL2IF BCL1IF HLVDIF TMR3IF TMR3GIF 75 PIE2 OSCFIE — SSP2IE BCL2IE BCL1IE HLVDIE TMR3IE TMR3GIE 75 PIR3 TMR5GIF(1) LCDIF RC2IF TX2IF CTMUIF CCP2IF CCP1IF RTCCIF 75 PIE3 TMR5GIE(1) LCDIE RC2IE TX2IE CTMUIE CCP2IE CCP1IE RTCCIE 75 TMR3H Timer3 Register High Byte TMR3L Timer3 Register Low Byte 75 75 T3GCON TMR3GE T3GPOL T3GTM T3GSPM T3GGO/ T3DONE T3GVAL T3GSS1 T3GSS0 75 T3CON TMR3CS1 TMR3CS0 T3CKPS1 T3CKPS0 SOSCEN T3SYNC RD16 TMR3ON 75 TMR5H Timer5 Register High Byte TMR5L Timer5 Register Low Byte 80 80 TMR5GE T5GPOL T5GTM T5GSPM T5GGO/ T5DONE T5GVAL T5GSS1 T5GSS0 80 T5CON TMR5CS1 TMR5CS0 T5CKPS1 T5CKPS0 SOSCEN T5SYNC RD16 TMR5ON 80 TMR7H Timer7 Register High Byte 79 TMR7L Timer7 Register Low Byte 79 T5GCON T7GCON TMR7GE T7CON T7GPOL T7GTM T7GSPM T7GGO/ T7DONE T7GVAL T7GSS1 T7GSS0 79 TMR7CS1 TMR7CS0 T7CKPS1 T7CKPS0 SOSCEN T7SYNC RD16 TMR7ON 79 OSCCON2 — SOSCRUN — — SOSCGO — MFIOFS MFIOSEL 77 CCPTMRS0 C3TSEL1 C3TSEL0 C2TSEL2 C2TSEL1 C2TSEL0 C1TSEL2 C1TSEL1 C1TSEL0 79 CCPTMRS1 C7TSEL1 C7TSEL0 — C6TSEL0 — C5TSEL0 C4TSEL1 C4TSEL0 79 CCPTMRS1 — — — C10TSEL0 — C9TSEL0 C8TSEL1 C8TSEL0 79 Legend: Note 1: — = unimplemented, read as ‘0’. Shaded cells are not used by the Timer3/5/7 module. Unimplemented on devices with a program memory of 32 Kbytes (PIC18FX5K90). 2010 Microchip Technology Inc. Preliminary DS39957B-page 209 PIC18F87K90 FAMILY NOTES: DS39957B-page 210 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 16.0 TIMER4/6/8/10/12 MODULES 16.1 The Timer4/6/8/10/12 timer modules have the following features: • • • • • • 8-Bit Timer register (TMRx) 8-Bit Period register (PRx) Readable and writable (all registers) Software programmable prescaler (1:1, 1:4, 1:16) Software programmable postscaler (1:1 to 1:16) Interrupt on TMRx match of PRx Timer10 and Timer12 are unimplemented for devices with program memory of 32 Kbytes (PIC18FX5K90). Note: Throughout this section, generic references are used for register and bit names that are the same, except for an ‘x’ variable that indicates the item’s association with the Timer4, Timer6, Timer8, Timer10 or Timer12 module. For example, the control register is named TxCON and refers to T4CON, T6CON, T8CON, T10CON and T12CON. The Timer4/6/8/10/12 modules have a control register shown in Register 16-1. Timer4/6/8/10/12 can be shut off by clearing control bit, TMRxON (TxCON<2>), to minimize power consumption. The prescaler and postscaler selection of Timer4/6/8/10/12 also are controlled by this register. Figure 16-1 is a simplified block diagram of the Timer4/6/8/10/12 modules. Timer4/6/8/10/12 Operation Timer4/6/8/10/12 can be used as the PWM time base for the PWM mode of the ECCP modules. The TMRx registers are readable and writable, and are cleared on any device Reset. The input clock (FOSC/4) has a prescale option of 1:1, 1:4 or 1:16, selected by control bits, TxCKPS<1:0> (TxCON<1:0>). The match output of TMRx goes through a 4-bit postscaler (that gives a 1:1 to 1:16 inclusive scaling) to generate a TMRx interrupt, latched in the flag bit, TMRxIF. Table 16-1 gives each module’s flag bit. TABLE 16-1: TIMER4/6/8/10/12 FLAG BITS Timer Module Flag Bit PIR5<x> Timer Module Flag Bit PIR5<x> 4 0 10 5 6 2 12 6 8 4 The interrupt can be enabled or disabled by setting or clearing the Timerx Interrupt Enable bit (TMRxIE), shown in Table 16-2. TABLE 16-2: TIMER4/6/8/10/12 INTERRUPT ENABLE BITS Timer Module Flag Bit PIE5<x> Timer Module Flag Bit PIE5<x> 4 0 10 5 6 2 12 6 8 4 The prescaler and postscaler counters are cleared when any of the following occurs: • A write to the TMRx register • A write to the TxCON register • Any device Reset (Power-on Reset (POR), MCLR Reset, Watchdog Timer Reset (WDTR) or Brown-out Reset (BOR)) A TMRx is not cleared when a TxCON is written. Note: 2010 Microchip Technology Inc. Preliminary The CCP and ECCP modules use Timers, 1 through 8, for some modes. The assignment of a particular timer to a CCP/ECCP module is determined by the Timer to CCP enable bits in the CCPTMRSx registers. For more details, see Register 19-2, Register 18-2 and Register 18-3. DS39957B-page 211 PIC18F87K90 FAMILY REGISTER 16-1: TxCON: TIMER4/6/8/10/12 CONTROL REGISTER U-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 — TxOUTPS3 TxOUTPS2 TxOUTPS1 TxOUTPS0 TMRxON TxCKPS1 TxCKPS0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7 Unimplemented: Read as ‘0’ bit 6-3 TxOUTPS<3:0>: Timerx Output Postscale Select bits 0000 = 1:1 Postscale 0001 = 1:2 Postscale • • • 1111 = 1:16 Postscale bit 2 TMRxON: Timerx On bit 1 = Timerx is on 0 = Timerx is off bit 1-0 TxCKPS<1:0>: Timerx Clock Prescale Select bits 00 = Prescaler is 1 01 = Prescaler is 4 1x = Prescaler is 16 16.2 Timer4/6/8/10/12 Interrupt 16.3 The Timer4/6/8/10/12 modules have 8-bit period registers, PRx, that are both readable and writable. Timer4/6/8/10/12 increment from 00h until they match PR4/6/8/10/12 and then reset to 00h on the next increment cycle. The PRx registers are initialized to FFh upon Reset. FIGURE 16-1: FOSC/4 Output of TMRx The outputs of TMRx (before the postscaler) are used only as a PWM time base for the ECCP modules. They are not used as baud rate clocks for the MSSP modules as is the Timer2 output. TIMER4/6/8/10/12 BLOCK DIAGRAM 4 TxOUTPS<3:0> TxCKPS<1:0> x = Bit is unknown 1:1 to 1:16 Postscaler Set TMRxIF 2 1:1, 1:4, 1:16 Prescaler TMRx Output (to PWM) Reset TMRx 8 TMRx/PRx Match Comparator 8 PRx 8 Internal Data Bus DS39957B-page 212 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY TABLE 16-3: Name REGISTERS ASSOCIATED WITH TIMER4/6/8/10/12 AS A TIMER/COUNTER Bit 7 INTCON Bit 6 GIE/GIEH (1) Bit 5 PEIE/GIEL (1) (1) Bit 3 INT0IE RBIE Bit 2 Bit 1 Bit 0 Reset Values on Page: TMR0IF INT0IF RBIF 73 (1) 74 IPR5 TMR7GIP TMR10IP TMR8IP TMR7IP TMR6IP TMR5IP TMR4IP PIR5 TMR7GIF(1) TMR12IF(1) TMR10IF(1) TMR8IF TMR7IF(1) TMR6IF TMR5IF TMR4IF 75 PIE5 TMR7GIE(1) TMR12IE(1) TMR10IE(1) TMR8IE TMR7IE(1) TMR6IE TMR5IE TMR4IE 75 TMR4 Timer4 Register T4OUTPS2 T4OUTPS1 T4OUTPS0 TMR4ON T4CKPS1 T4CKPS0 — T4CON TMR12IP TMR0IE Bit 4 80 T4OUTPS3 PR4 Timer4 Period Register TMR6 Timer6 Register — T6CON 79 T6OUTPS3 PR6 Timer6 Period Register TMR8 Timer8 Register — T8CON 80 80 T6OUTPS2 T6OUTPS1 T6OUTPS0 TMR6ON T6CKPS1 T6CKPS0 79 79 79 T8OUTPS3 T8OUTPS2 T8OUTPS1 T8OUTPS0 TMR8ON T8CKPS1 T8CKPS0 79 PR8 Timer8 Period Register 79 TMR10 Timer10 Register 79 — T10CON T10OUTPS3 T10OUTPS2 T10OUTPS1 T10OUTPS0 TMR10ON T10CKPS1 T10CKPS0 79 PR10 Timer10 Period Register 79 TMR12 Timer12 Register 79 — T12CON PR12 T12OUTPS3 T12OUTPS2 T12OUTPS1 T12OUTPS0 TMR12ON T12CKPS1 T12CKPS0 Timer12 Period Register 79 79 CCPTMRS0 C3TSEL1 C3TSEL0 C2TSEL2 C2TSEL1 C2TSEL0 C1TSEL2 C1TSEL1 C1TSEL0 79 CCPTMRS1 C7TSEL1 C7TSEL0 — C6TSEL0 — C5TSEL0 C4TSEL1 C4TSEL0 79 CCPTMRS2 — — — C10TSEL0(1) — C9TSEL0(1) C8TSEL1 C8TSEL0 79 Legend: Note 1: — = unimplemented, read as ‘0’. Shaded cells are not used by the Timer4/6/8/10/12 module. Unimplemented on devices with a program memory of 32k bytes (PIC18FX5K22). 2010 Microchip Technology Inc. Preliminary DS39957B-page 213 PIC18F87K90 FAMILY NOTES: DS39957B-page 214 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 17.0 REAL-TIME CLOCK AND CALENDAR (RTCC) The key features of the Real-Time Clock and Calendar (RTCC) module are: • • • • • • • • • • • • Time: hours, minutes and seconds Twenty-four hour format (military time) Calendar: weekday, date, month and year Alarm configurable Year range: 2000 to 2099 Leap year correction BCD format for compact firmware Optimized for low-power operation User calibration with auto-adjust Calibration range: 2.64 seconds error per month Requirements: external 32.768 kHz clock crystal Alarm pulse or seconds clock output on RTCC pin FIGURE 17-1: The RTCC module is intended for applications where accurate time must be maintained for an extended period with minimum to no intervention from the CPU. The module is optimized for low-power usage in order to provide extended battery life while keeping track of time. The module is a 100-year clock and calendar with automatic leap year detection. The range of the clock is from 00:00:00 (midnight) on January 1, 2000 to 23:59:59 on December 31, 2099. Hours are measured in 24-hour (military time) format. The clock provides a granularity of one second with half-second visibility to the user. RTCC BLOCK DIAGRAM RTCC Clock Domain CPU Clock Domain 32.768 kHz Input from SOSC Oscillator RTCCFG RTCC Prescalers Internal RC (LF-INTOSC) ALRMRPT YEAR 0.5s Alarm Event MTHDY RTCVALx RTCC Timer WKDYHR MINSEC Comparator ALMTHDY Compare Registers with Masks ALRMVALx ALWDHR ALMINSEC Repeat Counter RTCC Interrupt RTCC Interrupt Logic Alarm Pulse RTCC Pin RTCOE 2010 Microchip Technology Inc. Preliminary DS39957B-page 215 PIC18F87K90 FAMILY 17.1 RTCC MODULE REGISTERS Alarm Value Registers The RTCC module registers are divided into the following categories: RTCC Control Registers • • • • • RTCCFG RTCCAL PADCFG1 ALRMCFG ALRMRPT RTCC Value Registers • ALRMVALH • ALRMVALL Both registers access the following registers: - ALRMMNTH - ALRMDAY - ALRMWD - ALRMHR - ALRMMIN - ALRMSEC Note: • RTCVALH • RTCVALL Both registers access the following registers: - YEAR - MONTH - DAY - WEEKDAY - HOUR - MINUTE - SECOND DS39957B-page 216 Preliminary The RTCVALH and RTCVALL registers can be accessed through RTCRPT<1:0> (RTCCFG<1:0>). ALRMVALH and ALRMVALL can be accessed through ALRMPTR<1:0> (ALRMCFG<1:0>). 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 17.1.1 RTCC CONTROL REGISTERS REGISTER 17-1: R/W-0 RTCCFG: RTCC CONFIGURATION REGISTER(1) U-0 (2) RTCEN — R/W-0 R-0 (4) RTCWREN R-0 (3) RTCSYNC HALFSEC R/W-0 R/W-0 R/W-0 RTCOE RTCPTR1 RTCPTR0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 RTCEN: RTCC Enable bit(2) 1 = RTCC module is enabled 0 = RTCC module is disabled bit 6 Unimplemented: Read as ‘0’ bit 5 RTCWREN: RTCC Value Registers Write Enable bit(4) 1 = RTCVALH and RTCVALL registers can be written to by the user 0 = RTCVALH and RTCVALL registers are locked out from being written to by the user bit 4 RTCSYNC: RTCC Value Registers Read Synchronization bit 1 = RTCVALH, RTCVALL and ALRMRPT registers can change while reading if a rollover ripple results in an invalid data read. If the register is read twice and results in the same data, the data can be assumed to be valid. 0 = RTCVALH, RTCVALL and ALCFGRPT registers can be read without concern over a rollover ripple bit 3 HALFSEC: Half-Second Status bit(3) 1 = Second half period of a second 0 = First half period of a second bit 2 RTCOE: RTCC Output Enable bit 1 = RTCC clock output is enabled 0 = RTCC clock output is disabled bit 1-0 RTCPTR<1:0>: RTCC Value Register Window Pointer bits Points to the corresponding RTCC Value registers when reading the RTCVALH and RTCVALL registers. The RTCPTR<1:0> value decrements on every read or write of RTCVALH<15:8> until it reaches ‘00’. RTCVALH: 00 = Minutes 01 = Weekday 10 = Month 11 = Reserved RTCVALL: 00 = Seconds 01 = Hours 10 = Day 11 = Year Note 1: 2: 3: 4: The RTCCFG register is only affected by a POR. A write to the RTCEN bit is only allowed when RTCWREN = 1. This bit is read-only; it is cleared to ‘0’ on a write to the lower half of the MINSEC register. The RTCWREN bit can only be written with the unlock sequence (see Example 17-1). 2010 Microchip Technology Inc. Preliminary DS39957B-page 217 PIC18F87K90 FAMILY REGISTER 17-2: RTCCAL: RTCC CALIBRATION REGISTER R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 CAL7 CAL6 CAL5 CAL4 CAL3 CAL2 CAL1 CAL0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7-0 x = Bit is unknown CAL<7:0>: RTC Drift Calibration bits 01111111 = Maximum positive adjustment. Adds 508 RTC clock pulses every minute. . . . 00000001 = Minimum positive adjustment. Adds four RTC clock pulses every minute. 00000000 = No adjustment 11111111 = Minimum negative adjustment. Subtracts four RTC clock pulses every minute. . . . 10000000 = Maximum negative adjustment. Subtracts 512 RTC clock pulses every minute. REGISTER 17-3: R/W-0 RDPU PADCFG1: PAD CONFIGURATION REGISTER R/W-0 R/W-0 REPU RJPU(2) U-0 — U-0 R/W-0 R/W-0 U-0 — RTSECSEL1(1) RTSECSEL0(1) — bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 RDPU: PORTD Pull-up Enable bit 1 = PORTD pull-up resistors are enabled by individual port latch values 0 = All PORTD pull-up resistors are disabled bit 6 REPU: PORTE Pull-up Enable bit 1 = PORTE pull-up resistors are enabled by individual port latch values 0 = All PORTE pull-up resistors are disabled bit 5 RJPU: PORTJ Pull-up Enable bit(2) 1 = PORTJ pull-up resistors are enabled by individual port latch values 0 = All PORTJ pull-up resistors are disabled bit 4-3 Unimplemented: Read as ‘0’ bit 2-1 RTSECSEL<1:0>: RTCC Seconds Clock Output Select bit(1) 11 = Reserved; do not use 10 = RTCC source clock is selected for the RTCC pin (pin can be LF-INTOSC or SOSC, depending on the RTCOSC (CONFIG3L<1>) bit setting) 01 = RTCC seconds clock is selected for the RTCC pin 00 = RTCC alarm pulse is selected for the RTCC pin bit 0 Unimplemented: Read as ‘0’ Note 1: 2: To enable the actual RTCC output, the RTCOE (RTCCFG<2>) bit must be set. Available only in 80-pin parts. DS39957B-page 218 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY REGISTER 17-4: ALRMCFG: ALARM CONFIGURATION REGISTER R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 ALRMEN CHIME AMASK3 AMASK2 AMASK1 AMASK0 ALRMPTR1 ALRMPTR0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 ALRMEN: Alarm Enable bit 1 = Alarm is enabled (cleared automatically after an alarm event whenever ALRMPTR<1:0> = 00 and CHIME = 0) 0 = Alarm is disabled bit 6 CHIME: Chime Enable bit 1 = Chime is enabled; ALRMPTR<1:0> bits are allowed to roll over from 00h to FFh 0 = Chime is disabled; ALRMPTR<1:0> bits stop once they reach 00h bit 5-2 AMASK<3:0>: Alarm Mask Configuration bits 0000 = Every half second 0001 = Every second 0010 = Every 10 seconds 0011 = Every minute 0100 = Every 10 minutes 0101 = Every hour 0110 = Once a day 0111 = Once a week 1000 = Once a month 1001 = Once a year (except when configured for February 29th, once every four years) 101x = Reserved – Do not use 11xx = Reserved – Do not use bit 1-0 ALRMPTR<1:0>: Alarm Value Register Window Pointer bits Points to the corresponding Alarm Value registers when reading the ALRMVALH and ALRMVALL registers. The ALRMPTR<1:0> value decrements on every read or write of ALRMVALH until it reaches ‘00’. ALRMVALH: 00 = ALRMMIN 01 = ALRMWD 10 = ALRMMNTH 11 = Unimplemented ALRMVALL: 00 = ALRMSEC 01 = ALRMHR 10 = ALRMDAY 11 = Unimplemented 2010 Microchip Technology Inc. Preliminary DS39957B-page 219 PIC18F87K90 FAMILY REGISTER 17-5: ALRMRPT: ALARM REPEAT REGISTER R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 ARPT7 ARPT6 ARPT5 ARPT4 ARPT3 ARPT2 ARPT1 ARPT0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7-0 17.1.2 x = Bit is unknown ARPT<7:0>: Alarm Repeat Counter Value bits 11111111 = Alarm will repeat 255 more times . . . 00000000 = Alarm will not repeat The counter decrements on any alarm event. The counter is prevented from rolling over from 00h to FFh unless CHIME = 1. RTCVALH AND RTCVALL REGISTER MAPPINGS REGISTER 17-6: RESERVED REGISTER U-0 U-0 U-0 U-0 U-0 U-0 U-0 U-0 — — — — — — — — bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7-0 x = Bit is unknown Unimplemented: Read as ‘0’ DS39957B-page 220 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY REGISTER 17-7: YEAR: YEAR VALUE REGISTER(1) R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x YRTEN3 YRTEN2 YRTEN1 YRTEN0 YRONE3 YRONE2 YRONE1 YRONE0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7-4 YRTEN<3:0>: Binary Coded Decimal Value of Year’s Tens Digit bits Contains a value from 0 to 9. bit 3-0 YRONE<3:0>: Binary Coded Decimal Value of Year’s Ones Digit bits Contains a value from 0 to 9. Note 1: A write to the YEAR register is only allowed when RTCWREN = 1. REGISTER 17-8: MONTH: MONTH VALUE REGISTER(1) U-0 U-0 U-0 R/W-x R/W-x R/W-x R/W-x R/W-x — — — MTHTEN0 MTHONE3 MTHONE2 MTHONE1 MTHONE0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7-5 Unimplemented: Read as ‘0’ bit 4 MTHTEN0: Binary Coded Decimal Value of Month’s Tens Digit bits Contains a value of ‘0’ or ‘1’. bit 3-0 MTHONE<3:0>: Binary Coded Decimal Value of Month’s Ones Digit bits Contains a value from 0 to 9. Note 1: x = Bit is unknown A write to this register is only allowed when RTCWREN = 1. 2010 Microchip Technology Inc. Preliminary DS39957B-page 221 PIC18F87K90 FAMILY REGISTER 17-9: DAY: DAY VALUE REGISTER(1) U-0 U-0 R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x — — DAYTEN1 DAYTEN0 DAYONE3 DAYONE2 DAYONE1 DAYONE0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7-6 Unimplemented: Read as ‘0’ bit 5-4 DAYTEN<1:0>: Binary Coded Decimal value of Day’s Tens Digit bits Contains a value from 0 to 3. bit 3-0 DAYONE<3:0>: Binary Coded Decimal Value of Day’s Ones Digit bits Contains a value from 0 to 9. Note 1: A write to this register is only allowed when RTCWREN = 1. REGISTER 17-10: WEEKDAY: WEEKDAY VALUE REGISTER(1) U-0 U-0 U-0 U-0 U-0 R/W-x R/W-x R/W-x — — — — — WDAY2 WDAY1 WDAY0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7-3 Unimplemented: Read as ‘0’ bit 2-0 WDAY<2:0>: Binary Coded Decimal Value of Weekday Digit bits Contains a value from 0 to 6. Note 1: x = Bit is unknown A write to this register is only allowed when RTCWREN = 1. DS39957B-page 222 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY REGISTER 17-11: HOUR: HOUR VALUE REGISTER(1) U-0 U-0 R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x — — HRTEN1 HRTEN0 HRONE3 HRONE2 HRONE1 HRONE0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7-6 Unimplemented: Read as ‘0’ bit 5-4 HRTEN<1:0>: Binary Coded Decimal Value of Hour’s Tens Digit bits Contains a value from 0 to 2. bit 3-0 HRONE<3:0>: Binary Coded Decimal Value of Hour’s Ones Digit bits Contains a value from 0 to 9. Note 1: A write to this register is only allowed when RTCWREN = 1. REGISTER 17-12: MINUTE: MINUTE VALUE REGISTER U-0 R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x — MINTEN2 MINTEN1 MINTEN0 MINONE3 MINONE2 MINONE1 MINONE0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 Unimplemented: Read as ‘0’ bit 6-4 MINTEN<2:0>: Binary Coded Decimal Value of Minute’s Tens Digit bits Contains a value from 0 to 5. bit 3-0 MINONE<3:0>: Binary Coded Decimal Value of Minute’s Ones Digit bits Contains a value from 0 to 9. REGISTER 17-13: SECOND: SECOND VALUE REGISTER U-0 R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x — SECTEN2 SECTEN1 SECTEN0 SECONE3 SECONE2 SECONE1 SECONE0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 Unimplemented: Read as ‘0’ bit 6-4 SECTEN<2:0>: Binary Coded Decimal Value of Second’s Tens Digit bits Contains a value from 0 to 5. bit 3-0 SECONE<3:0>: Binary Coded Decimal Value of Second’s Ones Digit bits Contains a value from 0 to 9. 2010 Microchip Technology Inc. Preliminary DS39957B-page 223 PIC18F87K90 FAMILY 17.1.3 ALRMVALH AND ALRMVALL REGISTER MAPPINGS REGISTER 17-14: ALRMMNTH: ALARM MONTH VALUE REGISTER(1) U-0 U-0 U-0 R/W-x R/W-x R/W-x R/W-x R/W-x — — — MTHTEN0 MTHONE3 MTHONE2 MTHONE1 MTHONE0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7-5 Unimplemented: Read as ‘0’ bit 4 MTHTEN0: Binary Coded Decimal Value of Month’s Tens Digit bits Contains a value of ‘0’ or ‘1’. bit 3-0 MTHONE<3:0>: Binary Coded Decimal Value of Month’s Ones Digit bits Contains a value from 0 to 9. Note 1: A write to this register is only allowed when RTCWREN = 1. REGISTER 17-15: ALRMDAY: ALARM DAY VALUE REGISTER(1) U-0 U-0 R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x — — DAYTEN1 DAYTEN0 DAYONE3 DAYONE2 DAYONE1 DAYONE0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7-6 Unimplemented: Read as ‘0’ bit 5-4 DAYTEN<1:0>: Binary Coded Decimal Value of Day’s Tens Digit bits Contains a value from 0 to 3. bit 3-0 DAYONE<3:0>: Binary Coded Decimal Value of Day’s Ones Digit bits Contains a value from 0 to 9. Note 1: x = Bit is unknown A write to this register is only allowed when RTCWREN = 1. DS39957B-page 224 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY REGISTER 17-16: ALRMWD: ALARM WEEKDAY VALUE REGISTER(1) U-0 U-0 U-0 U-0 U-0 R/W-x R/W-x R/W-x — — — — — WDAY2 WDAY1 WDAY0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7-3 Unimplemented: Read as ‘0’ bit 2-0 WDAY<2:0>: Binary Coded Decimal Value of Weekday Digit bits Contains a value from 0 to 6. Note 1: A write to this register is only allowed when RTCWREN = 1. REGISTER 17-17: ALRMHR: ALARM HOURS VALUE REGISTER(1) U-0 U-0 R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x — — HRTEN1 HRTEN0 HRONE3 HRONE2 HRONE1 HRONE0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7-6 Unimplemented: Read as ‘0’ bit 5-4 HRTEN<1:0>: Binary Coded Decimal Value of Hour’s Tens Digit bits Contains a value from 0 to 2. bit 3-0 HRONE<3:0>: Binary Coded Decimal Value of Hour’s Ones Digit bits Contains a value from 0 to 9. Note 1: x = Bit is unknown A write to this register is only allowed when RTCWREN = 1. 2010 Microchip Technology Inc. Preliminary DS39957B-page 225 PIC18F87K90 FAMILY REGISTER 17-18: ALRMMIN: ALARM MINUTES VALUE REGISTER U-0 R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x — MINTEN2 MINTEN1 MINTEN0 MINONE3 MINONE2 MINONE1 MINONE0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 Unimplemented: Read as ‘0’ bit 6-4 MINTEN<2:0>: Binary Coded Decimal Value of Minute’s Tens Digit bits Contains a value from 0 to 5. bit 3-0 MINONE<3:0>: Binary Coded Decimal Value of Minute’s Ones Digit bits Contains a value from 0 to 9. REGISTER 17-19: ALRMSEC: ALARM SECONDS VALUE REGISTER U-0 R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x — SECTEN2 SECTEN1 SECTEN0 SECONE3 SECONE2 SECONE1 SECONE0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 Unimplemented: Read as ‘0’ bit 6-4 SECTEN<2:0>: Binary Coded Decimal Value of Second’s Tens Digit bits Contains a value from 0 to 5. bit 3-0 SECONE<3:0>: Binary Coded Decimal Value of Second’s Ones Digit bits Contains a value from 0 to 9. DS39957B-page 226 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 17.1.4 17.2 RTCEN BIT WRITE RTCWREN (RTCCFG<5>) must be set before a write to RTCEN can take place. Any write to the RTCEN bit, while RTCWREN = 0, will be ignored. Like the RTCEN bit, the RTCVALH and RTCVALL registers can only be written to when RTCWREN = 1. A write to these registers, while RTCWREN = 0, will be ignored. FIGURE 17-2: FIGURE 17-3: The register interface for the RTCC and alarm values is implemented using the Binary Coded Decimal (BCD) format. This simplifies the firmware when using the module as each of the digits is contained within its own 4-bit value (see Figure 17-2 and Figure 17-3). Day Month 0-9 0-1 Hours (24-hour format) 0-2 0-9 0-9 0-3 Minutes 0-5 Day Of Week 0-9 Seconds 0-9 0-5 0-9 0-6 1/2 Second Bit (binary format) 0/1 ALARM DIGIT FORMAT Day Month 0-1 Hours (24-hour format) 0-2 REGISTER INTERFACE TIMER DIGIT FORMAT Year 0-9 17.2.1 Operation 0-9 2010 Microchip Technology Inc. 0-9 0-3 Minutes 0-5 Day Of Week 0-9 0-6 Seconds 0-9 Preliminary 0-5 0-9 DS39957B-page 227 PIC18F87K90 FAMILY 17.2.2 CLOCK SOURCE As mentioned earlier, the RTCC module is intended to be clocked by an external Real-Time Clock (RTCC) crystal oscillating at 32.768 kHz, but an internal oscillator can be used. The RTCC clock selection is decided by the RTCOSC bit (CONFIG3L<0>). FIGURE 17-4: Calibration of the crystal can be done through this module to yield an error of 3 seconds or less per month. (For further details, see Section 17.2.9 “Calibration”.) CLOCK SOURCE MULTIPLEXING 32.768 kHz XTAL from SOSC 1:16384 Half Second Clock Half Second(1) Clock Prescaler(1) Internal RC One Second Clock CONFIG3L<0> Second Note 1: 17.2.2.1 Hour:Minute Day Day of Week Year Writing to the lower half of the MINSEC register resets all counters, allowing fraction of a second synchronization; clock prescaler is held in Reset when RTCEN = 0. Real-Time Clock Enable TABLE 17-1: The RTCC module can be clocked by an external 32.768 kHz crystal (SOSC oscillator), or the LF-INTOSC oscillator, which can be selected in CONFIG3L<0>. DIGIT CARRY RULES This section explains which timer values are affected when there is a rollover: • Time of Day: From 23:59:59 to 00:00:00 with a carry to the Day field • Month: From 12/31 to 01/01 with a carry to the Year field • Day of Week: From 6 to 0 with no carry (see Table 17-1) • Year Carry: From 99 to 00; this also surpasses the use of the RTCC DAY OF WEEK SCHEDULE Day of Week If the external clock is used, the SOSC oscillator should be enabled. If LF-INTOSC is providing the clock, the INTOSC clock can be brought out to the RTCC pin by the RTSECSEL<1:0> bits (PADCFG<2:1>). 17.2.3 Month Sunday 0 Monday 1 Tuesday 2 Wednesday 3 Thursday 4 Friday 5 Saturday 6 TABLE 17-2: DAY-TO-MONTH ROLLOVER SCHEDULE Month Maximum Day Field 01 (January) 31 02 (February) 28 or 29(1) 03 (March) 31 04 (April) 30 For the day-to-month rollover schedule, see Table 17-2. 05 (May) 31 Because the following values are in BCD format, the carry to the upper BCD digit occurs at the count of 10, not 16 (SECONDS, MINUTES, HOURS, WEEKDAY, DAYS and MONTHS). 06 (June) 30 07 (July) 31 08 (August) 31 09 (September) 30 10 (October) 31 11 (November) 30 12 (December) 31 Note 1: DS39957B-page 228 Preliminary See Section 17.2.4 “Leap Year”. 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 17.2.4 LEAP YEAR 17.2.7 Since the year range on the RTCC module is 2000 to 2099, the leap year calculation is determined by any year divisible by four in the above range. Only February is affected in a leap year. February will have 29 days in a leap year and 28 days in any other year. 17.2.5 GENERAL FUNCTIONALITY All Timer registers containing a time value of seconds or greater are writable. The user configures the time by writing the required year, month, day, hour, minutes and seconds to the Timer registers, via Register Pointers. (See Section 17.2.8 “Register Mapping”.) In order to perform a write to any of the RTCC Timer registers, the RTCWREN bit (RTCCFG<5>) must be set. To avoid accidental writes to the RTCC Timer register, it is recommended that the RTCWREN bit (RTCCFG<5>) be kept clear when not writing to the register. For the RTCWREN bit to be set, there is only one instruction cycle time window allowed between the 55h/AA sequence and the setting of RTCWREN. For that reason, it is recommended that users follow the code example in Example 17-1. EXAMPLE 17-1: The timer uses the newly written values and proceeds with the count from the required starting point. The RTCC is enabled by setting the RTCEN bit (RTCCFG<7>). If enabled while adjusting these registers, the timer still continues to increment. However, any time the MINSEC register is written to, both of the timer prescalers are reset to ‘0’. This allows fraction of a second synchronization. The Timer registers are updated in the same cycle as the write instruction’s execution by the CPU. The user must ensure that when RTCEN = 1, the updated registers will not be incremented at the same time. This can be accomplished in several ways: • By checking the RTCSYNC bit (RTCCFG<4>) • By checking the preceding digits from which a carry can occur • By updating the registers immediately following the seconds pulse (or an alarm interrupt) The user has visibility to the half-second field of the counter. This value is read-only and can be reset only by writing to the lower half of the SECONDS register. 17.2.6 SAFETY WINDOW FOR REGISTER READS AND WRITES movlw movwf movlw movwf bsf 17.2.8 2010 Microchip Technology Inc. SETTING THE RTCWREN BIT 0x55 EECON2 0xAA EECON2 RTCCFG,RTCWREN REGISTER MAPPING To limit the register interface, the RTCC Timer and Alarm Timer registers are accessed through corresponding Register Pointers. The RTCC Value register window (RTCVALH and RTCVALL) uses the RTCPTRx bits (RTCCFG<1:0>) to select the required Timer register pair. By reading or writing to the RTCVALH register, the RTCC Pointer value (RTCPTR<1:0>) decrements by ‘1’ until it reaches ‘00’. When ‘00’ is reached, the MINUTES and SECONDS value is accessible through RTCVALH and RTCVALL until the pointer value is manually changed. TABLE 17-3: RTCPTR<1:0> The RTCSYNC bit indicates a time window during which the RTCC clock domain registers can be safely read and written without concern about a rollover. When RTCSYNC = 0, the registers can be safely accessed by the CPU. Whether RTCSYNC = 1 or 0, the user should employ a firmware solution to ensure that the data read did not fall on a rollover boundary, resulting in an invalid or partial read. This firmware solution would consist of reading each register twice and then comparing the two values. If the two values matched, then a rollover did not occur. WRITE LOCK RTCVALH AND RTCVALL REGISTER MAPPING RTCC Value Register Window RTCVALH RTCVALL 00 MINUTES SECONDS 01 WEEKDAY HOURS 10 MONTH DAY 11 — YEAR The Alarm Value register windows (ALRMVALH and ALRMVALL) use the ALRMPTR bits (ALRMCFG<1:0>) to select the desired alarm register pair. By reading or writing to the ALRMVALH register, the Alarm Pointer value, ALRMPTR<1:0>, decrements by ‘1’ until it reaches ‘00’. When it reaches ‘00’, the ALRMMIN and ALRMSEC value is accessible through ALRMVALH and ALRMVALL until the pointer value is manually changed. Preliminary DS39957B-page 229 PIC18F87K90 FAMILY TABLE 17-4: 17.3 ALRMVAL REGISTER MAPPING ALRMPTR<1:0> 00 The Alarm features and characteristics are: Alarm Value Register Window ALRMVALH ALRMVALL ALRMMIN ALRMSEC 01 ALRMWD ALRMHR 10 ALRMMNTH ALRMDAY 11 — — 17.2.9 CALIBRATION To perform this calibration, find the number of error clock pulses and store the value into the lower half of the RTCCAL register. The 8-bit, signed value, loaded into RTCCAL, is multiplied by four and will be either added or subtracted from the RTCC timer, once every minute. 17.3.1 The interval selection of the alarm is configured through the ALRMCFG bits (AMASK<3:0>) (see Figure 17-5). These bits determine which and how many digits of the alarm must match the clock value for the alarm to occur. The alarm can also be configured to repeat based on a preconfigured interval. The number of times this occurs, after the alarm is enabled, is stored in the ALRMRPT register. Use another timer resource on the device to find the error of the 32.768 kHz crystal. Convert the number of error clock pulses per minute (see Equation 17-1). EQUATION 17-1: CONVERTING ERROR CLOCK PULSES (Ideal Frequency (32,758) – Measured Frequency) * 60 = Error Clocks per Minute 3. CONFIGURING THE ALARM This bit is cleared when an alarm is issued. The bit will not be cleared if the CHIME bit = 1 or if ALRMRPT 0. Note: To calibrate the RTCC module: 2. • Configurable from half a second to one year • Enabled using the ALRMEN bit (ALRMCFG<7>, Register 17-4) • Offers one-time and repeat alarm options The alarm feature is enabled using the ALRMEN bit. The real-time crystal input can be calibrated using the periodic auto-adjust feature. When properly calibrated, the RTCC can provide an error of less than three seconds per month. 1. Alarm While the alarm is enabled (ALRMEN = 1), changing any of the registers, other than the RTCCAL, ALRMCFG and ALRMRPT registers and the CHIME bit, can result in a false alarm event leading to a false alarm interrupt. To avoid this, only change the timer and alarm values while the alarm is disabled (ALRMEN = 0). It is recommended that the ALRMCFG and ALRMRPT registers and CHIME bit be changed when RTCSYNC = 0. • If the oscillator is faster than ideal (negative result from step 2), the RCFGCALL register value needs to be negative. This causes the specified number of clock pulses to be subtracted from the timer counter once every minute. • If the oscillator is slower than ideal (positive result from step 2), the RCFGCALL register value needs to be positive. This causes the specified number of clock pulses to be added to the timer counter once every minute. Load the RTCCAL register with the correct value. Writes to the RTCCAL register should occur only when the timer is turned off or immediately after the rising edge of the seconds pulse. Note: In determining the crystal’s error value, it is the user’s responsibility to include the crystal’s initial error from drift due to temperature or crystal aging. DS39957B-page 230 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY FIGURE 17-5: ALARM MASK SETTINGS Alarm Mask Setting AMASK<3:0> Day of the Week Month Day Hours Minutes Seconds 0000 – Every half second 0001 – Every second 0010 – Every 10 seconds s 0011 – Every minute s s m s s m m s s 0100 – Every 10 minutes 0101 – Every hour 0110 – Every day 0111 – Every week d 1000 – Every month 1001 – Every year(1) Note 1: m m h h m m s s h h m m s s d d h h m m s s d d h h m m s s Annually, except when configured for February 29. When ALRMCFG = 00 and the CHIME bit = 0 (ALRMCFG<6>), the repeat function is disabled and only a single alarm will occur. The alarm can be repeated up to 255 times by loading the ALRMRPT register with FFh. After each alarm is issued, the ALRMRPT register is decremented by one. Once the register has reached ‘00’, the alarm will be issued one last time. After the alarm is issued a last time, the ALRMEN bit is cleared automatically and the alarm turned off. Indefinite repetition of the alarm can occur if the CHIME bit = 1. When CHIME = 1, the alarm is not disabled when the ALRMRPT register reaches ‘00’, but it rolls over to FF and continues counting indefinitely. 17.3.2 ALARM INTERRUPT At every alarm event, an interrupt is generated. Additionally, an alarm pulse output is provided that operates at half the frequency of the alarm. The alarm pulse output is completely synchronous with the RTCC clock and can be used as a trigger clock to other peripherals. This output is available on the RTCC pin. The output pulse is a clock with a 50% duty cycle and a frequency half that of the alarm event (see Figure 17-6). The RTCC pin also can output the seconds clock. The user can select between the alarm pulse, generated by the RTCC module, or the seconds clock output. The RTSECSEL<1:0> bits (PADCFG1<2:1>) select between these two outputs: • Alarm pulse – RTSECSEL<1:0> = 00 • Seconds clock – RTSECSEL<1:0> = 01 2010 Microchip Technology Inc. Preliminary DS39957B-page 231 PIC18F87K90 FAMILY FIGURE 17-6: TIMER PULSE GENERATION RTCEN bit ALRMEN bit RTCC Alarm Event RTCC Pin 17.4 Sleep Mode 17.5 The timer and alarm continue to operate while in Sleep mode. The operation of the alarm is not affected by Sleep, as an alarm event can always wake up the CPU. The Idle mode does not affect the operation of the timer or alarm. 17.5.1 Reset DEVICE RESET When a device Reset occurs, the ALRMRPT register is forced to its Reset state causing the alarm to be disabled (if enabled prior to the Reset). If the RTCC was enabled, it will continue to operate when a basic device Reset occurs. 17.5.2 POWER-ON RESET (POR) The RTCCFG and ALRMRPT registers are reset only on a POR. Once the device exits the POR state, the clock registers should be reloaded with the desired values. The timer prescaler values can be reset only by writing to the SECONDS register. No device Reset can affect the prescalers. DS39957B-page 232 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 17.6 Register Maps Table 17-5, Table 17-6 and Table 17-7 summarize the registers associated with the RTCC module. TABLE 17-5: File Name RTCC CONTROL REGISTERS Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 All Resets on Page: RTCCFG RTCEN — RTCWREN RTCSYNC HALFSEC RTCOE RTCPTR1 RTCPTR0 78 RTCCAL CAL7 CAL6 CAL5 CAL4 CAL3 CAL2 CAL1 CAL0 78 PADCFG1 RDPU REPU RJPU(1) — — — 78 ALRMCFG ALRMEN CHIME AMASK3 AMASK2 AMASK1 AMASK0 ARPT7 ARPT6 ARPT5 ARPT4 ARPT3 ARPT2 ALRMRPT Legend: Note 1: RTSECSEL1 RTSECSEL0 ALRMPTR1 ALRMPTR0 ARPT1 ARPT0 78 78 — = unimplemented, read as ‘0’. Reset values are shown in hexadecimal for 80-pin devices. Not available on 64-pin devices. TABLE 17-6: File Name RTCC VALUE REGISTERS Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 All Resets on Page: RTCVALH RTCC Value High Register Window Based on RTCPTR<1:0> 78 RTCVALL RTCC Value Low Register Window Based on RTCPTR<1:0> 78 Legend: — = unimplemented, read as ‘0’. Reset values are shown in hexadecimal for 80-pin devices. TABLE 17-7: File Name ALARM VALUE REGISTERS Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 All Resets on Page: ALRMVALH Alarm Value High Register Window Based on ALRMPTR<1:0> 78 ALRMVALL 78 Legend: Alarm Value Low Register Window Based on ALRMPTR<1:0> — = unimplemented, read as ‘0’. Reset values are shown in hexadecimal for 80-pin devices. 2010 Microchip Technology Inc. Preliminary DS39957B-page 233 PIC18F87K90 FAMILY NOTES: DS39957B-page 234 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 18.0 CAPTURE/COMPARE/PWM (CCP) MODULES PIC18F87K90 family devices have seven CCP (Capture/Compare/PWM) modules, designated CCP4 through CCP10. All the modules implement standard Capture, Compare and Pulse-Width Modulation (PWM) modes. Note: Each CCP module contains a 16-bit register that can operate as a 16-bit Capture register, a 16-bit Compare register or a PWM Master/Slave Duty Cycle register. For the sake of clarity, all CCP module operation in the following sections is described with respect to CCP4, but is equally applicable to CCP5 through CCP10. Note: Throughout this section, generic references are used for register and bit names that are the same, except for an ‘x’ variable that indicates the item’s association with the specific CCP module. For example, the control register is named CCPxCON and refers to CCP4CON through CCP10CON. REGISTER 18-1: The CCP9 and CCP10 modules are disabled on the devices with 32 Kbytes of program memory (PIC18FX5K90). CCPxCON: CCPx CONTROL REGISTER (CCP4-CCP10 MODULES)(1) U-0 U-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 — — DCxB1 DCxB0 CCPxM3 CCPxM2 CCPxM1 CCPxM0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7-6 Unimplemented: Read as ‘0’ bit 5-4 DCxB<1:0>: PWM Duty Cycle for CCPx Module bits (bit 1, bit 0) Capture mode: Unused. Compare mode: Unused. PWM mode: These bits are the two Least Significant bits (bit 1 and bit 0) of the 10-bit PWM duty cycle. The eight Most Significant bits (DCxB<9:2>) of the duty cycle are found in CCPRxL. bit 3-0 CCPxM<3:0>: CCPx Module Mode Select bits 0000 = Capture/Compare/PWM disabled (resets CCPx module) 0001 = Reserved 0010 = Compare mode: toggle output on match (CCPxIF bit is set) 0011 = Reserved 0100 = Capture mode: every falling edge 0101 = Capture mode: every rising edge 0110 = Capture mode: every 4th rising edge 0111 = Capture mode: every 16th rising edge 1000 = Compare mode: initialize CCPx pin low; on compare match, force CCPx pin high (CCPxIF bit is set) 1001 = Compare mode: initialize CCPx pin high; on compare match, force CCPx pin low (CCPxIF bit is set) 1010 = Compare mode: generate software interrupt on compare match (CCPxIF bit is set, CCPx pin reflects I/O state) 1011 = Compare mode: Special Event Trigger; reset timer on CCPx match (CCPxIF bit is set)(2) 11xx = PWM mode Note 1: 2: The CCP9 and CCP10 modules are not available on devices with 32 Kbytes of program memory (PIC18FX5K90). CCPxM<3:0> = 1011 will only reset the timer and not start A/D conversion on CCPx match. 2010 Microchip Technology Inc. Preliminary DS39957B-page 235 PIC18F87K90 FAMILY REGISTER 18-2: CCPTMRS1: CCPx TIMER SELECT REGISTER 1 R/W-0 R/W-0 U-0 R/W-0 U-0 R/W-0 R/W-0 R/W-0 C7TSEL1 C7TSEL0 — C6TSEL0 — C5TSEL0 C4TSEL1 C4TSEL0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7-6 C7TSEL<1:0>: CCP7 Timer Selection bits 00 = CCP7 is based off of TMR1/TMR2 01 = CCP7 is based off of TMR5/TMR4 10 = CCP7 is based off of TMR5/TMR6 11 = CCP7 is based off of TMR5/TMR8 bit 5 Unimplemented: Read as ‘0’ bit 4 C6TSEL0: CCP6 Timer Selection bit 0 = CCP6 is based off of TMR1/TMR2 1 = CCP6 is based off of TMR5/TMR2 bit 3 Unimplemented: Read as ‘0’ bit 2 C5TSEL0: CCP5 Timer Selection bit 0 = CCP5 is based off of TMR1/TMR2 1 = CCP5 is based off of TMR5/TMR4 bit 1-0 C4TSEL<1:0>: CCP4 Timer Selection bits 00 = CCP4 is based off of TMR1/TMR2 01 = CCP4 is based off of TMR3/TMR4 10 = CCP4 is based off of TMR3/TMR6 11 = Reserved; do not use DS39957B-page 236 Preliminary x = Bit is unknown 2010 Microchip Technology Inc. PIC18F87K90 FAMILY REGISTER 18-3: CCPTMRS2: CCPx TIMER SELECT REGISTER 2 U-0 U-0 U-0 R/W-0 U-0 R/W-0 R/W-0 R/W-0 — — — C10TSEL0(1) — C9TSEL0(1) C8TSEL1 C8TSEL0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7-5 Unimplemented: Read as ‘0’ bit 4 C10TSEL0: CCP10 Timer Selection bit(1) 0 = CCP10 is based off of TMR1/TMR2 1 = CCP10 is based off of TMR7/TMR2 bit 3 Unimplemented: Read as ‘0’ bit 2 C9TSEL0: CCP9 Timer Selection bit 0 = CCP9 is based off of TMR1/TMR2 1 = CCP9 is based off of TMR7/TMR4 bit 1-0 C8TSEL<1:0>: CCP8 Timer Selection bits On non 32-Kbyte device variants: 00 = CCP8 is based off of TMR1/TMR2 01 = CCP8 is based off of TMR7/TMR4 10 = CCP8 is based off of TMR7/TMR6 11 = Reserved; do not use On 32-Kbyte device variants (PIC18F85K90/65K90: 00 = CCP8 is based off of TMR1/TMR2 01 = CCP8 is based off of TMR1/TMR4 10 = CCP8 is based off of TMR1/TMR6 11 = Reserved; do not use Note 1: x = Bit is unknown This bit is unimplemented and reads as ‘0’ on devices with 32 Kbytes of program memory (PIC18FX5K90). 2010 Microchip Technology Inc. Preliminary DS39957B-page 237 PIC18F87K90 FAMILY REGISTER 18-4: CCPRxL: CCPx PERIOD LOW BYTE REGISTER R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x CCPRxL7 CCPRxL6 CCPRxL5 CCPRxL4 CCPRxL3 CCPRxL2 CCPRxL1 CCPRxL0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7-0 x = Bit is unknown CCPRxL<7:0>: CCPx Period Register Low Byte bits Capture Mode: Capture register low byte. Compare Mode: Compare register low byte. PWM Mode: Duty Cycle register low byte. REGISTER 18-5: CCPRxH: CCPx PERIOD HIGH BYTE REGISTER R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x CCPRxH7 CCPRxH6 CCPRxH5 CCPRxH4 CCPRxH3 CCPRxH2 CCPRxH1 CCPRxH0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7-0 x = Bit is unknown CCPRxH<7:0>: CCPx Period Register High Byte bits Capture Mode: Capture register high byte. Compare Mode: Compare register high byte. PWM Mode: Duty Cycle Buffer register high byte. DS39957B-page 238 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 18.1 CCP Module Configuration TABLE 18-1: Each Capture/Compare/PWM module is associated with a control register (generically, CCPxCON) and a data register (CCPRx). The data register, in turn, is comprised of two 8-bit registers: CCPRxL (low byte) and CCPRxH (high byte). All registers are both readable and writable. 18.1.1 CCP MODE – TIMER RESOURCE CCP Mode Timer Resource Capture Timer1, Timer3, Timer 5 or Timer7 Compare PWM Timer2, Timer4, Timer 6 or Timer8 The assignment of a particular timer to a module is determined by the Timer to CCP enable bits in the CCPTMRSx registers. (See Register 18-2 and Register 18-3.) All of the modules may be active at once and may share the same timer resource if they are configured to operate in the same mode (Capture/Compare or PWM) at the same time. CCP MODULES AND TIMER RESOURCES The CCP modules utilize Timers, 1 through 8, varying with the selected mode. Various timers are available to the CCP modules in Capture, Compare or PWM modes, as shown in Table 18-1. The CCPTMRS1 register selects the timers for CCP modules, 7, 6, 5 and 4, and the CCPTMRS2 register selects the timers for CCP modules, 10, 9 and 8. The possible configurations are shown in Table 18-2 and Table 18-3. TABLE 18-2: TIMER ASSIGNMENTS FOR CCP MODULES 4, 5, 6 AND 7 CCPTMRS1 Register CCP4 CCP5 Capture/ C4TSEL Compare <1:0> Mode 0 0 TMR1 Capture/ PWM C6TSEL0 Compare Mode Mode Capture/ PWM PWM C7TSEL Compare Mode Mode <1:0> Mode TMR2 0 TMR1 TMR2 0 TMR1 TMR2 0 0 TMR1 TMR2 1 TMR5 TMR4 1 TMR5 TMR2 0 1 TMR5 TMR4 1 0 TMR5 TMR6 1 1 TMR5 TMR8 0 1 TMR3 TMR4 TMR3 TMR6 1 1 CCP7 Capture/ PWM C5TSEL0 Compare Mode Mode 1 0 Note 1: CCP6 Reserved(1) Do not use the reserved bits. TABLE 18-3: TIMER ASSIGNMENTS FOR CCP MODULES 8, 9 AND 10 CCPTMRS2 Register CCP8 Devices with 32 Kbytes(1) CCP8 CCP9(1) CCP10(1) Capture/ Capture/ Capture/ Capture/ C8TSEL PWM C8TSEL PWM PWM PWM Compare Compare C9TSEL0 Compare C10TSEL0 Compare <1:0> Mode <1:0> Mode Mode Mode Mode Mode Mode Mode 0 0 TMR1 TMR2 0 0 TMR1 TMR2 0 TMR1 TMR2 0 TMR1 TMR2 1 TMR7 TMR4 1 TMR7 TMR2 0 1 TMR7 TMR4 0 1 TMR1 TMR4 1 0 TMR7 TMR6 1 0 TMR1 TMR6 1 1 Note 1: 2: Reserved(2) 1 1 Reserved(2) Module not available for devices with 32 Kbytes of program memory. Do not use the reserved bits. 2010 Microchip Technology Inc. Preliminary DS39957B-page 239 PIC18F87K90 FAMILY 18.1.2 18.2 OPEN-DRAIN OUTPUT OPTION When operating in Output mode (the Compare or PWM modes), the drivers for the CCPx pins can be optionally configured as open-drain outputs. This feature allows the voltage level on the pin to be pulled to a higher level through an external pull-up resistor and allows the output to communicate with external circuits without the need for additional level shifters. The open-drain output option is controlled by the CCPxOD bits (ODCON2<7:2>). Setting the appropriate bit configures the pin for the corresponding module for open-drain operation. 18.1.3 PIN ASSIGNMENT FOR CCP6, CCP7, CCP8 AND CCP9 The pin assignment for CCP6/7/8/9 (Capture input, Compare and PWM output) can change, based on the device configuration. The ECCPMX Configuration bit (CONFIG3H<1>) determines the pin to which CCP6/7/8/9 is multiplexed. The pin assignments for these CCP modules are given in Table 18-4. TABLE 18-4: ECCPMX Value CCP PIN ASSIGNMENT In Capture mode, the CCPR4H:CCPR4L register pair captures the 16-bit value of the TMR1 or TMR3 register when an event occurs on the CCP4 pins. An event is defined as one of the following: • • • • Every falling edge Every rising edge Every 4th rising edge Every 16th rising edge The event is selected by the mode select bits, CCP4M<3:0> (CCP4CON<3:0>). When a capture is made, the interrupt request flag bit, CCP4IF (PIR4<1>), is set. (It must be cleared in software.) If another capture occurs before the value in CCPR4 is read, the old captured value is overwritten by the new captured value. Figure 18-1 shows the Capture mode block diagram. 18.2.1 Note: CCP7 CCP8 CC9 1 (Default) RE6 RE5 RE4 RE3 0 RH7 RH6 RH5 RH4 CCP PIN CONFIGURATION In Capture mode, the appropriate CCPx pin should be configured as an input by setting the corresponding TRIS direction bit. Pin Mapped To CCP6 Capture Mode 18.2.2 If RC1 or RE7 is configured as a CCP4 output, a write to the port causes a capture condition. TIMER1/3/5/7 MODE SELECTION For the available timers (1/3/5/7) to be used for the capture feature, the used timers must be running in Timer mode or Synchronized Counter mode. In Asynchronous Counter mode, the capture operation may not work. The timer to be used with each CCP module is selected in the CCPTMRSx registers. (See Section 18.1.1 “CCP Modules and Timer Resources”.) Details of the timer assignments for the CCP modules are given in Table 18-2 and Table 18-3. DS39957B-page 240 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY FIGURE 18-1: CAPTURE MODE OPERATION BLOCK DIAGRAM TMR5H Set CCP5IF C5TSEL0 CCP5 Pin Prescaler 1, 4, 16 and Edge Detect CCP5CON<3:0> Q1:Q4 CCP4CON<3:0> 4 4 CCPR5L TMR1 Enable TMR1H TMR1L TMR3H TMR3L Set CCP4IF 4 C4TSEL1 C4TSEL0 TMR3 Enable CCP4 Pin Prescaler 1, 4, 16 TMR5 Enable CCPR5H C5TSEL0 TMR5L and Edge Detect CCPR4H CCPR4L TMR1 Enable C4TSEL0 C4TSEL1 Note: 18.2.3 TMR1L This block diagram uses CCP4 and CCP5, and their appropriate timers, as an example. For details on all of the CCP modules and their timer assignments, see Table 18-2 and Table 18-3. SOFTWARE INTERRUPT When the Capture mode is changed, a false capture interrupt may be generated. The user should keep the CCP4IE bit (PIE4<1>) clear to avoid false interrupts and should clear the flag bit, CCP4IF, following any such change in operating mode. 18.2.4 TMR1H CCP PRESCALER There are four prescaler settings in Capture mode. They are specified as part of the operating mode selected by the mode select bits (CCP4M<3:0>). Whenever the CCP module is turned off, or the CCP module is not in Capture mode, the prescaler counter is cleared. This means that any Reset will clear the prescaler counter. 2010 Microchip Technology Inc. Switching from one capture prescaler to another may generate an interrupt. Doing that also will not clear the prescaler counter – meaning the first capture may be from a non-zero prescaler. Example 18-1 shows the recommended method for switching between capture prescalers. This example also clears the prescaler counter and will not generate the “false” interrupt. EXAMPLE 18-1: CHANGING BETWEEN CAPTURE PRESCALERS CLRF CCP4CON ; Turn CCP module off MOVLW NEW_CAPT_PS ; Load WREG with the ; new prescaler mode ; value and CCP ON MOVWF CCP4CON ; Load CCP4CON with ; this value Preliminary DS39957B-page 241 PIC18F87K90 FAMILY 18.3 Compare Mode 18.3.3 SOFTWARE INTERRUPT MODE In Compare mode, the 16-bit CCPR4 register value is constantly compared against either the TMR1 or TMR3 register pair value. When a match occurs, the CCP4 pin can be: When the Generate Software Interrupt mode is chosen (CCP4M<3:0> = 1010), the CCP4 pin is not affected. Only a CCP interrupt is generated, if enabled, and the CCP4IE bit is set. • • • • 18.3.4 Driven high Driven low Toggled (high-to-low or low-to-high) Unchanged (that is, reflecting the state of the I/O latch) The action on the pin is based on the value of the mode select bits (CCP4M<3:0>). At the same time, the interrupt flag bit, CCP4IF, is set. Figure 18-2 shows the Compare mode block diagram 18.3.1 CCP PIN CONFIGURATION The user must configure the CCPx pin as an output by clearing the appropriate TRIS bit. Note: 18.3.2 Clearing the CCP4CON register will force the RC1 or RE7 compare output latch (depending on device configuration) to the default low level. This is not the PORTC or PORTE I/O data latch. SPECIAL EVENT TRIGGER Both CCP modules are equipped with a Special Event Trigger. This is an internal hardware signal generated in Compare mode to trigger actions by other modules. The Special Event Trigger is enabled by selecting the Compare Special Event Trigger mode (CCP4M<3:0> = 1011). For either CCP module, the Special Event Trigger resets the timer register pair for whichever timer resource is currently assigned as the module’s time base. This allows the CCPRx registers to serve as a programmable period register for either timer. The Special Event Trigger for CCP4 cannot start an A/D conversion. Note: TIMER1/3/5/7 MODE SELECTION The Special Event Trigger of ECCP1 can start an A/D conversion, but the A/D Converter needs to be enabled. For more information, see Section 19.0 “Enhanced Capture/Compare/PWM (ECCP) Module”. If the CCP module is using the compare feature in conjunction with any of the Timer1/3/5/7 timers, the timers must be running in Timer mode or Synchronized Counter mode. In Asynchronous Counter mode, the compare operation may not work. Note: Details of the timer assignments for the CCP modules are given in Table 18-2 and Table 18-3. DS39957B-page 242 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY FIGURE 18-2: COMPARE MODE OPERATION BLOCK DIAGRAM CCPR5H Set CCP5IF CCPR5L Special Event Trigger (Timer1/5 Reset) CCP5 Pin Compare Match Comparator S Output Logic Q R TRIS Output Enable 4 CCP5CON<3:0> TMR1H TMR1L 0 TMR5H TMR5L 1 C5TSEL0 0 TMR1H TMR1L 1 TMR3H TMR3L Special Event Trigger (Timer1/Timer3 Reset, A/D Trigger) C4TSEL1 C4TSEL0 Set CCP4IF Comparator CCPR4H CCP4 Pin Compare Match Output Logic 4 CCPR4L S Q R TRIS Output Enable CCP4CON<3:0> Note: This block diagram uses CCP4 and CCP5, and their appropriate timers, as an example. For details on all of the CCP modules and their timer assignments, see Table 18-2 and Table 18-3. 2010 Microchip Technology Inc. Preliminary DS39957B-page 243 PIC18F87K90 FAMILY TABLE 18-5: Name INTCON REGISTERS ASSOCIATED WITH CAPTURE, COMPARE, TIMER1/3/5/7 Bit 7 Bit 6 Bit 5 GIE/GIEH PEIE/GIEL TMR0IE Bit 2 Bit 1 Bit 0 Reset Values on Page: INT0IE RBIE TMR0IF INT0IF RBIF 73 RI TO PD POR BOR 74 CCP10IF(1) CCP9IF(1) CCP8IF CCP7IF CCP6IF CCP5IF CCP4IF CCP3IF 75 PIE4 CCP10IE(1) CCP9IE(1) CCP8IE CCP7IE CCP6IE CCP5IE CCP4IE CCP3IE 75 IPR4 CCP10IP(1) CCP9IP(1) CCP8IP CCP7IP CCP6IP CCP5IP CCP4IP CCP3IP 75 IPEN CM Bit 3 PIR4 RCON SBOREN Bit 4 TRISB TRISB7 TRISB6 TRISB5 TRISB4 TRISB3 TRISB2 TRISB1 TRISB0 76 TRISC TRISC7 TRISC6 TRISC5 TRISC4 TRISC3 TRISC2 TRISC1 TRISC0 76 TRISE TRISE7 TRISE6 TRISE5 TRISE4 TRISE3 TRISE2 TRISE1 TRISE0 76 TRISH(1) TRISH7 TRISH6 TRISH5 TRISH4 TRISH3 TRISH2 TRISH1 TRISH0 76 TMR1L Timer1 Register Low Byte 74 TMR1H Timer1 Register High Byte 74 TMR3L Timer3 Register Low Byte 75 TMR3H Timer3 Register High Byte 75 TMR5L Timer5 Register Low Byte 80 TMR5H Timer5 Register High Byte 80 TMR7L Timer7 Register Low Byte 79 TMR7H Timer7 Register High Byte 79 T1CON TMR1CS1 TMR1CS0 T1CKPS1 T1CKPS0 SOSCEN T1SYNC RD16 TMR1ON 74 T3CON TMR3CS1 TMR3CS0 T3CKPS1 T3CKPS0 SOSCEN T3SYNC RD16 TMR3ON 75 T5CON TMR5CS1 TMR5CS0 T5CKPS1 T5CKPS0 SOSCEN T5SYNC RD16 TMR5ON 80 T7CON TMR7CS1 TMR7CS0 T7CKPS1 T7CKPS0 SOSCEN T7SYNC RD16 TMR7ON 79 CCPR4L Capture/Compare/PWM Register 4 Low Byte 80 CCPR4H Capture/Compare/PWM Register 4 High Byte 80 CCPR5L Capture/Compare/PWM Register 5 Low Byte 80 CCPR5H Capture/Compare/PWM Register 5 High Byte 80 CCPR6L Capture/Compare/PWM Register 6 Low Byte 80 CCPR6H Capture/Compare/PWM Register 6 High Byte 80 CCPR7L Capture/Compare/PWM Register 7 Low Byte 80 CCPR7H Capture/Compare/PWM Register 7 High Byte 80 CCPR8L Capture/Compare/PWM Register 8 Low Byte 78 CCPR8H Capture/Compare/PWM Register 8 High Byte 78 CCPR9L(1) Capture/Compare/PWM Register 9 Low Byte 78 CCPR9H(1) Capture/Compare/PWM Register 9 High Byte 78 (1) Capture/Compare/PWM Register 10 Low Byte 79 CCPR10H(1) Capture/Compare/PWM Register 10 High Byte 78 CCPR10L CCP4CON — — DC4B1 DC4B0 CCP4M3 CCP4M2 CCP4M1 CCP4M0 80 CCP5CON — — DC5B1 DC5B0 CCP5M3 CCP5M2 CCP5M1 CCP5M0 80 Legend: — = unimplemented, read as ‘0’. Shaded cells are not used by Capture/Compare or Timer1/3/5/7. Note 1: Unimplemented on devices with a program memory of 32 Kbytes (PIC18FX5K90). DS39957B-page 244 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY TABLE 18-5: REGISTERS ASSOCIATED WITH CAPTURE, COMPARE, TIMER1/3/5/7 (CONTINUED) Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Reset Values on Page: CCP6CON — — DC6B1 DC6B0 CCP6M3 CCP6M2 CCP6M1 CCP6M0 80 CCP7CON — — DC7B1 DC7B0 CCP7M3 CCP7M2 CCP7M1 CCP7M0 80 CCP8CON — — DC8B1 DC8B0 CCP8M3 CCP8M2 CCP8M1 CCP8M0 78 CCP9CON — — DC9B1 DC9B0 CCP9M3 CCP9M2 CCP9M1 CCP9M0 78 CCP10CON(1) — — DC10B1 DC10B0 CCP10M3 CCP10M2 CCP10M1 CCP10M0 79 Name (1) CCPTMRS1 CCPTMRS2 C7TSEL1 C7TSEL0 — — — C6TSEL0 — C5TSEL0 C4TSEL1 C4TSEL0 79 — C10TSEL0 — C9TSEL0 C8TSEL1 C8TSEL0 79 Legend: — = unimplemented, read as ‘0’. Shaded cells are not used by Capture/Compare or Timer1/3/5/7. Note 1: Unimplemented on devices with a program memory of 32 Kbytes (PIC18FX5K90). 18.4 PWM Mode FIGURE 18-3: In Pulse-Width Modulation (PWM) mode, the CCP4 pin produces up to a 10-bit resolution PWM output. Since the CCP4 pin is multiplexed with a PORTC or PORTE data latch, the appropriate TRIS bit must be cleared to make the CCP4 pin an output. Note: Clearing the CCP4CON register will force the RC1 or RE7 output latch (depending on device configuration) to the default low level. This is not the PORTC or PORTE I/O data latch. Duty Cycle Registers CCP4CON<5:4> CCPR4L CCPR4H (Slave) R Comparator Q RC2/ECCP1 Figure 18-3 shows a simplified block diagram of the ECCP1 module in PWM mode. TMR2 For a step-by-step procedure on how to set up the CCP module for PWM operation, see Section 18.4.3 “Setup for PWM Operation”. Comparator PR2 Note 1: 2: 2010 Microchip Technology Inc. SIMPLIFIED PWM BLOCK DIAGRAM Preliminary (Note 1) S TRISC<2> Clear Timer, ECCP1 Pin and latch D.C. The 8-bit TMR2 value is concatenated with the 2-bit internal Q clock, or 2 bits of the prescaler, to create the 10-bit time base. CCP4 and its appropriate timers are used as an example. For details on all of the CCP modules and their timer assignments, see Table 18-2 and Table 18-3. DS39957B-page 245 PIC18F87K90 FAMILY A PWM output (Figure 18-4) has a time base (period) and a time that the output stays high (duty cycle). The frequency of the PWM is the inverse of the period (1/period). FIGURE 18-4: PWM OUTPUT Period Duty Cycle TMR2 = PR2 PWM PERIOD The PWM period is specified by writing to the PR2 register. The PWM period can be calculated using the following formula: EQUATION 18-1: PWM Period = [(PR2) + 1] • 4 • TOSC • (TMR2 Prescale Value) CCPR4L and CCP4CON<5:4> can be written to at any time, but the duty cycle value is not latched into CCPR4H until after a match between PR2 and TMR2 occurs (that is, the period is complete). In PWM mode, CCPR4H is a read-only register. The CCPR4H register and a 2-bit internal latch are used to double-buffer the PWM duty cycle. This double-buffering is essential for glitchless PWM operation. When the CCPR4H and 2-bit latch match TMR2, concatenated with an internal 2-bit Q clock or two bits of the TMR2 prescaler, the CCP4 pin is cleared. PWM frequency is defined as 1/[PWM period]. When TMR2 is equal to PR2, the following three events occur on the next increment cycle: The maximum PWM resolution (bits) for a given PWM frequency is given by the equation: EQUATION 18-3: • TMR2 is cleared • The CCP4 pin is set (An exception: If PWM duty cycle = 0%, the CCP4 pin will not be set) • The PWM duty cycle is latched from CCPR4L into CCPR4H F OSC log --------------- F PWM PWM Resolution (max) = -----------------------------bits log 2 The Timer2 postscalers (see Section 14.0 “Timer2 Module”) are not used in the determination of the PWM frequency. The postscaler could be used to have a servo update rate at a different frequency than the PWM output. TABLE 18-6: The PWM duty cycle is specified by writing to the CCPR4L register (using CCP4 as an example) and to the CCP4CON<5:4> bits. Up to 10-bit resolution is available. The CCPR4L contains the eight MSbs and the CCP4CON<5:4> contains the two LSbs. This 10-bit value is represented by CCPR4L:CCP4CON<5:4>. The following equation is used to calculate the PWM duty cycle in time: PWM Duty Cycle = (CCPR4L:CCP4CON<5:4>) • TOSC • (TMR2 Prescale Value) TMR2 = Duty Cycle Note: PWM DUTY CYCLE EQUATION 18-2: TMR2 = PR2 18.4.1 18.4.2 Note: If the PWM duty cycle value is longer than the PWM period, the CCP4 pin will not be cleared. EXAMPLE PWM FREQUENCIES AND RESOLUTIONS AT 40 MHz PWM Frequency Timer Prescaler (1, 4, 16) PR2 Value Maximum Resolution (bits) DS39957B-page 246 2.44 kHz 9.77 kHz 39.06 kHz 156.25 kHz 312.50 kHz 416.67 kHz 16 4 1 1 1 1 FFh FFh FFh 3Fh 1Fh 17h 14 12 10 8 7 6.58 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 18.4.3 SETUP FOR PWM OPERATION 3. To configure the CCP module for PWM operation (with CCP4 as an example): 1. 4. Set the PWM period by writing to the PR2 register. Set the PWM duty cycle by writing to the CCPR4L register and CCP4CON<5:4> bits. 2. TABLE 18-7: Name INTCON RCON Make the CCP4 pin an output by clearing the appropriate TRIS bit. Set the TMR2 prescale value, then enable Timer2 by writing to T2CON. Configure the CCP4 module for PWM operation. 5. REGISTERS ASSOCIATED WITH PWM AND TIMERS Reset Values on Page: Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 GIE/GIEH PEIE/GIEL TMR0IE INT0IE RBIE TMR0IF INT0IF RBIF 73 IPEN SBOREN CM RI TO PD POR BOR 74 PIR4 CCP10IF(1) CCP9IF(1) CCP8IF CCP7IF CCP6IF CCP5IF CCP4IF CCP3IF 75 PIE4 (1) CCP10IE CCP9IE(1) CCP8IE CCP7IE CCP6IE CCP5IE CCP4IE CCP3IE 75 IPR4 CCP10IP(1) CCP9IP(1) CCP8IP CCP7IP CCP6IP CCP5IP CCP4IP CCP3IP 75 TRISB TRISB7 TRISB6 TRISB5 TRISB4 TRISB3 TRISB2 TRISB1 TRISB0 76 TRISC TRISC7 TRISC6 TRISC5 TRISC4 TRISC3 TRISC2 TRISC1 TRISC0 76 TRISE TRISE7 TRISE6 TRISE5 TRISE4 TRISE3 TRISE2 TRISE1 TRISE0 76 TRISH TRISH7 TRISH6 TRISH5 TRISH4 TRISH3 TRISH2 TRISH1 TRISH0 76 TMR2 Timer2 Register 74 TMR4 Timer4 Register 80 TMR6 Timer6 Register 79 TMR8 Timer8 Register 79 PR2 Timer2 Period Register 74 PR4 Timer4 Period Register 80 PR6 Timer6 Period Register 79 PR8 Timer8 Period Register 79 T2CON — T2OUTPS3 T2OUTPS2 T2OUTPS1 T2OUTPS0 TMR2ON T2CKPS1 T2CKPS0 74 T4CON — T4OUTPS3 T4OUTPS2 T4OUTPS1 T4OUTPS0 TMR4ON T4CKPS1 T4CKPS0 80 T6CON — T6OUTPS3 T6OUTPS2 T6OUTPS1 T6OUTPS0 TMR6ON T6CKPS1 T6CKPS0 79 — T8OUTPS3 T8OUTPS2 T8OUTPS1 T8OUTPS0 TMR8ON T8CKPS1 T8CKPS0 T8CON 79 CCPR4L Capture/Compare/PWM Register 4 Low Byte 80 CCPR4H Capture/Compare/PWM Register 4 High Byte 80 CCPR5L Capture/Compare/PWM Register 5 Low Byte 80 CCPR5H Capture/Compare/PWM Register 5 High Byte 80 CCPR6L Capture/Compare/PWM Register 6 Low Byte 80 CCPR6H Capture/Compare/PWM Register 6 High Byte 80 CCPR7L Capture/Compare/PWM Register 7 Low Byte 80 CCPR7H Capture/Compare/PWM Register 7 High Byte 80 CCPR8L Capture/Compare/PWM Register 8 Low Byte 78 CCPR8H Capture/Compare/PWM Register 8 High Byte 78 (1) CCPR9L Capture/Compare/PWM Register 9 Low Byte 78 CCPR9H(1) Capture/Compare/PWM Register 9 High Byte 78 CCPR10L(1) Capture/Compare/PWM Register 10 Low Byte 79 Legend: Note 1: — = unimplemented, read as ‘0’. Shaded cells are not used by PWM or Timer2/4/6/8. Unimplemented on devices with a program memory of 32 Kbytes (PIC18FX5K90). 2010 Microchip Technology Inc. Preliminary DS39957B-page 247 PIC18F87K90 FAMILY TABLE 18-7: Name REGISTERS ASSOCIATED WITH PWM AND TIMERS (CONTINUED) Bit 7 CCPR10H(1) Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Reset Values on Page: Capture/Compare/PWM Register 10 High Byte 78 CCP4CON — — DC4B1 DC4B0 CCP4M3 CCP4M2 CCP4M1 CCP4M0 80 CCP5CON — — DC5B1 DC5B0 CCP5M3 CCP5M2 CCP5M1 CCP5M0 80 CCP6CON — — DC6B1 DC6B0 CCP6M3 CCP6M2 CCP6M1 CCP6M0 80 CCP7CON — — DC7B1 DC7B0 CCP7M3 CCP7M2 CCP7M1 CCP7M0 80 CCP8CON — — DC8B1 DC8B0 CCP8M3 CCP8M2 CCP8M1 CCP8M0 78 CCP9CON(1) — — DC9B1 DC9B0 CCP9M3 CCP9M2 CCP9M1 CCP9M0 78 CCP10CON(1) — — DC10B1 DC10B0 CCP10M3 CCP10M2 CCP10M1 CCP10M0 79 CCPTMRS1 C7TSEL1 C7TSEL0 — C6TSEL0 — C5TSEL0 C4TSEL1 C4TSEL0 79 CCPTMRS2 — — — C10TSEL0 — C9TSEL0 C8TSEL1 C8TSEL0 79 Legend: Note 1: — = unimplemented, read as ‘0’. Shaded cells are not used by PWM or Timer2/4/6/8. Unimplemented on devices with a program memory of 32 Kbytes (PIC18FX5K90). DS39957B-page 248 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 19.0 ENHANCED CAPTURE/COMPARE/PWM (ECCP) MODULE ECCP1, ECCP2 and ECCP3 are implemented as standard CCP modules with Enhanced PWM capabilities. These include: PIC18F87K90 family devices have three Enhanced Capture/Compare/PWM (ECCP) modules: ECCP1, ECCP2 and ECCP3. These modules contain a 16-bit register, which can operate as a 16-bit Capture register, a 16-bit Compare register or a PWM Master/Slave Duty Cycle register. These ECCP modules are upward compatible with CCP Note: Throughout this section, generic references are used for register and bit names that are the same, except for an ‘x’ variable that indicates the item’s association with the ECCP1, ECCP2 or ECCP3 module. For example, the control register is named CCPxCON and refers to CCP1CON, CCP2CON and CCP3CON. 2010 Microchip Technology Inc. • • • • • Provision for two or four output channels Output Steering modes Programmable polarity Programmable dead-band control Automatic shutdown and restart The enhanced features are discussed in detail in Section 19.4 “PWM (Enhanced Mode)”. The ECCP1, ECCP2 and ECCP3 modules use the control registers, CCP1CON, CCP2CON and CCP3CON. The control registers, CCP4CON through CCP10CON, are for the CCP4 through CCP10 modules. Preliminary DS39957B-page 249 PIC18F87K90 FAMILY REGISTER 19-1: CCPxCON: ENHANCED CAPTURE/COMPARE/PWM x CONTROL R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 PxM1 PxM0 DCxB1 DCxB0 CCPxM3 CCPxM2 CCPxM1 CCPxM0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7-6 PxM<1:0>: Enhanced PWM Output Configuration bits If CCPxM<3:2> = 00, 01, 10: xx = PxA is assigned as a capture/compare input/output; PxB, PxC and PxD are assigned as port pins If CCPxM<3:2> = 11: 00 = Single output: PxA, PxB, PxC and PxD are controlled by steering (see Section 19.4.7 “Pulse Steering Mode”) 01 = Full-bridge output forward: PxD is modulated; PxA is active; PxB, PxC are inactive 10 = Half-bridge output: PxA, PxB are modulated with dead-band control; PxC and PxD are assigned as port pins 11 = Full-bridge output reverse: PxB is modulated; PxC is active; PxA and PxD are inactive bit 5-4 DCxB<1:0>: PWM Duty Cycle bit 1 and bit 0 Capture mode: Unused. Compare mode: Unused. PWM mode: These bits are the two LSbs of the 10-bit PWM duty cycle. The eight MSbs of the duty cycle are found in CCPRxL. bit 3-0 CCPxM<3:0>: ECCPx Mode Select bits 0000 = Capture/Compare/PWM off (resets ECCPx module) 0001 = Reserved 0010 = Compare mode: toggle output on match 0011 = Capture mode 0100 = Capture mode: every falling edge 0101 = Capture mode: every rising edge 0110 = Capture mode: every fourth rising edge 0111 = Capture mode: every 16th rising edge 1000 = Compare mode: initialize the ECCPx pin low; set the output on a compare match (set CCPxIF) 1001 = Compare mode: initialize the ECCPx pin high; clear the output on a compare match (set CCPxIF) 1010 = Compare mode: generate a software interrupt only, ECCPx pin reverts to an I/O state 1011 = Compare mode: trigger special event (ECCPx resets TMR1 or TMR3, starts A/D conversion, sets CCxIF bit) 1100 = PWM mode: PxA and PxC are active-high; PxB and PxD are active-high 1101 = PWM mode: PxA and PxC are active-high; PxB and PxD are active-low 1110 = PWM mode: PxA and PxC are active-low; PxB and PxD are active-high 1111 = PWM mode: PxA and PxC are active-low; PxB and PxD are active-low DS39957B-page 250 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY REGISTER 19-2: CCPTMRS0: CCP TIMER SELECT 0 REGISTER R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 C3TSEL1 C3TSEL0 C2TSEL2 C2TSEL1 C2TSEL0 C1TSEL2 C1TSEL1 C1TSEL0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7-6 C3TSEL<1:0>: ECCP3 Timer Selection bit 00 = ECCP3 is based off of TMR1/TMR2 01 = ECCP3 is based off of TMR3/TMR4 10 = ECCP3 is based off of TMR3/TMR6 11 = ECCP3 is based off of TMR3/TMR8 bit 5-3 C2TSEL<2:0>: ECCP2 Timer Selection bit 000 = ECCP2 is based off of TMR1/TMR2 001 = ECCP2 is based off of TMR3/TMR4 010 = ECCP2 is based off of TMR3/TMR6 011 = ECCP2 is based off of TMR3/TMR8 100 = ECCP2 is based off of TMR3/TMR10; option is reserved on the 32-Kbyte device variant; do not use 101 = Reserved; do not use 110 = Reserved; do not use 111 = Reserved; do not use bit 2-0 C1TSEL<2:0>: ECCP1 Timer Selection bit 000 = ECCP1 is based off of TMR1/TMR2 001 = ECCP1 is based off of TMR3/TMR4 010 = ECCP1 is based off of TMR3/TMR6 011 = ECCP1 is based off of TMR3/TMR8 100 = ECCP1 is based off of TMR3/TMR10; option is reserved on the 32-Kbyte device variant; do not use 101 = ECCP1 is based off of TMR3/TMR12; option is reserved on the 32-Kbyte device variant; do not use 110 = Reserved; do not use 111 = Reserved; do not use 2010 Microchip Technology Inc. Preliminary DS39957B-page 251 PIC18F87K90 FAMILY In addition to the expanded range of modes available through the CCPxCON and ECCPxAS registers, the ECCP modules have two additional registers associated with Enhanced PWM operation and auto-shutdown features. They are: • ECCPxDEL – Enhanced PWM Control • PSTRxCON – Pulse Steering Control 19.1 ECCP Outputs and Configuration The Enhanced CCP module may have up to four PWM outputs, depending on the selected operating mode. The CCPxCON register is modified to allow control over four PWM outputs: ECCPx/PxA, PxB, PxC and PxD. Applications can use one, two or four of these outputs. The outputs that are active depend on the ECCP operating mode selected. The pin assignments are summarized in Table 19-3. To configure the I/O pins as PWM outputs, the proper PWM mode must be selected by setting the PxM<1:0> and CCPxM<3:0> bits. The appropriate TRIS direction bits for the port pins must also be set as outputs. 19.1.1 ECCP MODULE AND TIMER RESOURCES The ECCP modules use Timers, 1, 2, 3, 4, 6, 8, 10 or 12, depending on the mode selected. These timers are available to CCP modules in Capture, Compare or PWM modes, as shown in Table 19-1. TABLE 19-1: ECCP MODE – TIMER RESOURCE ECCP Mode Timer Resource Capture Timer1 or Timer3 19.1.2 ECCP PIN ASSIGNMENT The pin assignment for ECCPx (capture input, compare and PWM output) can change, based on device configuration. The ECCPMX (CONFIG3H<1>) Configuration bit determines to which pin, ECCP1 and ECCP3, are multiplexed to. • Default/ECCPMX = 1: - ECCP1 (P1B/P1C) multiplexed onto RE6 and RE5 - ECCP3 (P3B/P3C) multiplexed onto RE4 and RE3 • ECCPMX = 0: - ECCP1 (P1B/P1C) multiplexed onto RH7 and RH6 - ECCP3 (P3B/P3C) multiplexed onto RH5 and RH4. The pin assignment for ECCP2 (capture input, compare and PWM output) can change, based on device configuration. The CCP2MX Configuration bit (CONFIG3H<0>) determines to which pin, ECCP2, is multiplexed. • If CCP2MX = 1 (default) – ECCP2 is multiplexed to RC1 • If CCP2MX = 0 – ECCP2 is multiplexed to: - RE7 is the ECCP2 pin with CCP2MX = 0 Compare Timer1 or Timer3 PWM Timer2, Timer4, Timer6, Timer8, Timer10 or Timer12 DS39957B-page 252 The assignment of a particular timer to a module is determined by the Timer to ECCP enable bits in the CCPTMRSx register (Register 19-2). The interactions between the two modules are depicted in Figure 19-1. Capture operations are designed to be used when the timer is configured for Synchronous Counter mode. Capture operations may not work as expected if the associated timer is configured for Asynchronous Counter mode. Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 19.2 Capture Mode 19.2.2 In Capture mode, the CCPRxH:CCPRxL register pair captures the 16-bit value of the TMR1 or TMR3 registers when an event occurs on the corresponding ECCPx pin. An event is defined as one of the following: • • • • Every falling edge Every rising edge Every fourth rising edge Every 16th rising edge TABLE 19-2: ECCP1/2/3 INTERRUPT FLAG BITS ECCP Module Flag Bit 1 PIR3<1> 2 PIR3<2> 3 PIR4<0> 19.2.1 ECCP PIN CONFIGURATION In Capture mode, the appropriate ECCPx pin should be configured as an input by setting the corresponding TRIS direction bit. Note: The timers that are to be used with the capture feature (Timer1 and/or Timer3) must be running in Timer mode or Synchronized Counter mode. In Asynchronous Counter mode, the capture operation may not work. The timer to be used with each ECCP module is selected in the CCPTMRS0 register (Register 19-2). 19.2.3 The event is selected by the mode select bits, CCPxM<3:0> (CCPxCON register<3:0>). When a capture is made, the interrupt request flag bit, CCPxIF, is set (see Table 19-2). The flag must be cleared by software. If another capture occurs before the value in the CCPRxH/L register is read, the old captured value is overwritten by the new captured value. If the ECCPx pin is configured as an output, a write to the port can cause a capture condition. SOFTWARE INTERRUPT When the Capture mode is changed, a false capture interrupt may be generated. The user should keep the CCPxIE interrupt enable bit clear to avoid false interrupts. The interrupt flag bit, CCPxIF, should also be cleared following any such change in operating mode. 19.2.4 ECCP PRESCALER There are four prescaler settings in Capture mode; they are specified as part of the operating mode selected by the mode select bits (CCPxM<3:0>). Whenever the ECCP module is turned off, or Capture mode is disabled, the prescaler counter is cleared. This means that any Reset will clear the prescaler counter. Switching from one capture prescaler to another may generate an interrupt. Also, the prescaler counter will not be cleared; therefore, the first capture may be from a non-zero prescaler. Example 19-1 provides the recommended method for switching between capture prescalers. This example also clears the prescaler counter and will not generate the “false” interrupt. EXAMPLE 19-1: CLRF MOVLW MOVWF FIGURE 19-1: TIMER1/TIMER3 MODE SELECTION CHANGING BETWEEN CAPTURE PRESCALERS CCP1CON ; Turn ECCP module off NEW_CAPT_PS ; Load WREG with the ; new prescaler mode ; value and ECCP ON CCP1CON ; Load CCP1CON with ; this value CAPTURE MODE OPERATION BLOCK DIAGRAM Set CCP1IF ECCP1 Pin Prescaler 1, 4, 16 TMR3H C1TSEL0 C1TSEL1 C1TSEL2 and Edge Detect CCP1CON<3:0> Q1:Q4 2010 Microchip Technology Inc. TMR3 Enable CCPR1H C1TSEL0 C1TSEL1 C1TSEL2 CCPR1L TMR1 Enable TMR1H 4 TMR3L TMR1L 4 Preliminary DS39957B-page 253 PIC18F87K90 FAMILY 19.3 Compare Mode 19.3.2 TIMER1/TIMER3 MODE SELECTION In Compare mode, the 16-bit CCPRx register value is constantly compared against either the TMR1 or TMR3 register pair value. When a match occurs, the ECCPx pin can be: Timer1 and/or Timer3 must be running in Timer mode or Synchronized Counter mode if the ECCP module is using the compare feature. In Asynchronous Counter mode, the compare operation will not work reliably. • • • • 19.3.3 Driven high Driven low Toggled (high-to-low or low-to-high) Unchanged (that is, reflecting the state of the I/O latch) The action on the pin is based on the value of the mode select bits (CCPxM<3:0>). At the same time, the interrupt flag bit, CCPxIF, is set. 19.3.1 ECCP PIN CONFIGURATION Users must configure the ECCPx pin as an output by clearing the appropriate TRIS bit. Note: Clearing the CCPxCON register will force the ECCPx compare output latch (depending on device configuration) to the default low level. This is not the PORTx I/O data latch. FIGURE 19-2: SOFTWARE INTERRUPT MODE When the Generate Software Interrupt mode is chosen (CCPxM<3:0> = 1010), the ECCPx pin is not affected; only the CCPxIF interrupt flag is affected. 19.3.4 SPECIAL EVENT TRIGGER The ECCP module is equipped with a Special Event Trigger. This is an internal hardware signal generated in Compare mode to trigger actions by other modules. The Special Event Trigger is enabled by selecting the Compare Special Event Trigger mode (CCPxM<3:0> = 1011). The Special Event Trigger resets the Timer register pair for whichever timer resource is currently assigned as the module’s time base. This allows the CCPRx registers to serve as a programmable period register for either timer. The Special Event Trigger can also start an A/D conversion. In order to do this, the A/D Converter must already be enabled. COMPARE MODE OPERATION BLOCK DIAGRAM 0 TMR1H TMR1L 1 TMR3H TMR3L Special Event Trigger (Timer1/Timer3 Reset, A/D Trigger) C1TSEL0 C1TSEL1 C1TSEL2 Set CCP1IF Comparator CCPR1H ECCP1 Pin Compare Match Output Logic 4 CCPR1L S Q R TRIS Output Enable CCP1CON<3:0> DS39957B-page 254 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 19.4 PWM (Enhanced Mode) The PWM outputs are multiplexed with I/O pins and are designated: PxA, PxB, PxC and PxD. The polarity of the PWM pins is configurable and is selected by setting the CCPxM bits in the CCPxCON register appropriately. The Enhanced PWM mode can generate a PWM signal on up to four different output pins with up to 10 bits of resolution. It can do this through four different PWM Output modes: • • • • Table 19-1 provides the pin assignments for each Enhanced PWM mode. Single PWM Half-Bridge PWM Full-Bridge PWM, Forward mode Full-Bridge PWM, Reverse mode Figure 19-3 provides an example of a simplified block diagram of the Enhanced PWM module. Note: To select an Enhanced PWM mode, the PxM bits of the CCPxCON register must be set appropriately. FIGURE 19-3: To prevent the generation of an incomplete waveform when the PWM is first enabled, the ECCP module waits until the start of a new PWM period before generating a PWM signal. EXAMPLE SIMPLIFIED BLOCK DIAGRAM OF THE ENHANCED PWM MODE Duty Cycle Registers DC1B<1:0> CCPxM<3:0> 4 PxM<1:0> 2 CCPR1L ECCPx/PxA ECCP1/Output Pin TRIS CCPR1H (Slave) PxB Comparator R Q Output Controller Output Pin TRIS PxC TMR2 (1) S Comparator PR2 Note 1: Note: Output Pin TRIS PxD Clear Timer2, Toggle PWM Pin and Latch Duty Cycle Output Pin TRIS ECCP1DEL The 8-bit TMR2 register is concatenated with the 2-bit internal Q clock, or 2 bits of the prescaler to create the 10-bit time base. The TRIS register value for each PWM output must be configured appropriately. Any pin not used by an Enhanced PWM mode is available for alternate pin functions. 2010 Microchip Technology Inc. Preliminary DS39957B-page 255 PIC18F87K90 FAMILY TABLE 19-3: EXAMPLE PIN ASSIGNMENTS FOR VARIOUS PWM ENHANCED MODES ECCP Mode PxM<1:0> PxA PxB PxC PxD Single 00 Yes(1) Yes(1) Yes(1) Yes(1) Half-Bridge 10 Yes Yes No No Full-Bridge, Forward 01 Yes Yes Yes Yes Full-Bridge, Reverse 11 Yes Yes Yes Yes Note 1: Outputs are enabled by pulse steering in Single mode (see Register 19-5). FIGURE 19-4: EXAMPLE PWM (ENHANCED MODE) OUTPUT RELATIONSHIPS (ACTIVE-HIGH STATE) PxM<1:0> Signal 0 PR2 + 1 Pulse Width Period 00 (Single Output) PxA Modulated Delay(1) Delay(1) PxA Modulated 10 (Half-Bridge) PxB Modulated PxA Active 01 (Full-Bridge, Forward) PxB Inactive PxC Inactive PxD Modulated PxA Inactive 11 (Full-Bridge, Reverse) PxB Modulated PxC Active PxD Inactive Relationships: • Period = 4 * TOSC * (PR2 + 1) * (TMR2 Prescale Value) • Pulse Width = TOSC * (CCPRxL<7:0>:CCPxCON<5:4>) * (TMR2 Prescale Value) • Delay = 4 * TOSC * (ECCPxDEL<6:0>) Note 1: Dead-band delay is programmed using the ECCPxDEL register (Section 19.4.6 “Programmable Dead-Band Delay Mode”). DS39957B-page 256 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY FIGURE 19-5: EXAMPLE ENHANCED PWM OUTPUT RELATIONSHIPS (ACTIVE-LOW STATE) PxM<1:0> Signal PR2 + 1 Pulse Width 0 Period 00 (Single Output) PxA Modulated PxA Modulated 10 (Half-Bridge) Delay(1) Delay(1) PxB Modulated PxA Active 01 (Full-Bridge, Forward) PxB Inactive PxC Inactive PxD Modulated PxA Inactive 11 (Full-Bridge, Reverse) PxB Modulated PxC Active PxD Inactive Relationships: • Period = 4 * TOSC * (PR2 + 1) * (TMR2 Prescale Value) • Pulse Width = TOSC * (CCPRxL<7:0>:CCPxCON<5:4>) * (TMR2 Prescale Value) • Delay = 4 * TOSC * (ECCPxDEL<6:0>) Note 1: Dead-band delay is programmed using the ECCP1DEL register (Section 19.4.6 “Programmable Dead-Band Delay Mode”). 2010 Microchip Technology Inc. Preliminary DS39957B-page 257 PIC18F87K90 FAMILY 19.4.1 HALF-BRIDGE MODE In Half-Bridge mode, two pins are used as outputs to drive push-pull loads. The PWM output signal is output on the PxA pin, while the complementary PWM output signal is output on the PxB pin (see Figure 19-6). This mode can be used for half-bridge applications, as shown in Figure 19-7, or for full-bridge applications, where four power switches are being modulated with two PWM signals. Since the PxA and PxB outputs are multiplexed with the port data latches, the associated TRIS bits must be cleared to configure PxA and PxB as outputs. FIGURE 19-6: Period Period Pulse Width In Half-Bridge mode, the programmable dead-band delay can be used to prevent shoot-through current in half-bridge power devices. The value of the PxDC<6:0> bits of the ECCPxDEL register sets the number of instruction cycles before the output is driven active. If the value is greater than the duty cycle, the corresponding output remains inactive during the entire cycle. For more details on the dead-band delay operations, see Section 19.4.6 “Programmable Dead-Band Delay Mode”. PxA(2) td td PxB(2) (1) (1) (1) td = Dead-Band Delay Note 1: At this time, the TMR2 register is equal to the PR2 register. 2: FIGURE 19-7: EXAMPLE OF HALF-BRIDGE PWM OUTPUT Output signals are shown as active-high. EXAMPLE OF HALF-BRIDGE APPLICATIONS Standard Half-Bridge Circuit (“Push-Pull”) FET Driver + PxA Load FET Driver + PxB - Half-Bridge Output Driving a Full-Bridge Circuit V+ FET Driver FET Driver PxA FET Driver Load FET Driver PxB DS39957B-page 258 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 19.4.2 FULL-BRIDGE MODE In the Reverse mode, the PxC pin is driven to its active state and the PxB pin is modulated, while the PxA and PxD pins are driven to their inactive state, as provided Figure 19-9. In Full-Bridge mode, all four pins are used as outputs. An example of a full-bridge application is provided in Figure 19-8. The PxA, PxB, PxC and PxD outputs are multiplexed with the port data latches. The associated TRIS bits must be cleared to configure the PxA, PxB, PxC and PxD pins as outputs. In the Forward mode, the PxA pin is driven to its active state and the PxD pin is modulated, while the PxB and PxC pins are driven to their inactive state, as provided in Figure 19-9. FIGURE 19-8: EXAMPLE OF FULL-BRIDGE APPLICATION V+ FET Driver QC QA FET Driver PxA Load PxB FET Driver PxC FET Driver QD QB VPxD 2010 Microchip Technology Inc. Preliminary DS39957B-page 259 PIC18F87K90 FAMILY FIGURE 19-9: EXAMPLE OF FULL-BRIDGE PWM OUTPUT Forward Mode Period PxA (2) Pulse Width PxB(2) PxC(2) PxD(2) (1) (1) Reverse Mode Period Pulse Width PxA(2) PxB(2) PxC(2) PxD(2) (1) Note 1: 2: (1) At this time, the TMR2 register is equal to the PR2 register. The output signal is shown as active-high. DS39957B-page 260 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 19.4.2.1 Direction Change in Full-Bridge Mode In the Full-Bridge mode, the PxM1 bit in the CCPxCON register allows users to control the forward/reverse direction. When the application firmware changes this direction control bit, the module will change to the new direction on the next PWM cycle. A direction change is initiated in software by changing the PxM1 bit of the CCPxCON register. The following sequence occurs prior to the end of the current PWM period: • The modulated outputs (PxB and PxD) are placed in their inactive state. • The associated unmodulated outputs (PxA and PxC) are switched to drive in the opposite direction. • PWM modulation resumes at the beginning of the next period. For an illustration of this sequence, see Figure 19-10. The Full-Bridge mode does not provide a dead-band delay. As one output is modulated at a time, a dead-band delay is generally not required. There is a situation where a dead-band delay is required. This situation occurs when both of the following conditions are true: FIGURE 19-10: • The direction of the PWM output changes when the duty cycle of the output is at or near 100%. • The turn-off time of the power switch, including the power device and driver circuit, is greater than the turn-on time. Figure 19-11 shows an example of the PWM direction changing from forward to reverse, at a near 100% duty cycle. In this example, at time, t1, the PxA and PxD outputs become inactive, while the PxC output becomes active. Since the turn-off time of the power devices is longer than the turn-on time, a shoot-through current will flow through power devices, QC and QD (see Figure 19-8), for the duration of ‘t’. The same phenomenon will occur to power devices, QA and QB, for PWM direction change from reverse to forward. If changing PWM direction at high duty cycle is required for an application, two possible solutions for eliminating the shoot-through current are: • Reduce PWM duty cycle for one PWM period before changing directions. • Use switch drivers that can drive the switches off faster than they can drive them on. Other options to prevent shoot-through current may exist. EXAMPLE OF PWM DIRECTION CHANGE Period(1) Signal Period PxA (Active-High) PxB (Active-High) Pulse Width PxC (Active-High) (2) PxD (Active-High) Pulse Width Note 1: 2: The direction bit, PxM1 of the CCPxCON register, is written any time during the PWM cycle. When changing directions, the PxA and PxC signals switch before the end of the current PWM cycle. The modulated PxB and PxD signals are inactive at this time. The length of this time is: (1/FOSC) • TMR2 Prescale Value. 2010 Microchip Technology Inc. Preliminary DS39957B-page 261 PIC18F87K90 FAMILY FIGURE 19-11: EXAMPLE OF PWM DIRECTION CHANGE AT NEAR 100% DUTY CYCLE Forward Period t1 Reverse Period PxA PxB PW PxC PxD PW TON External Switch C TOFF External Switch D Potential Shoot-Through Current Note 1: 19.4.3 T = TOFF – TON All signals are shown as active-high. 2: TON is the turn-on delay of power switch, QC, and its driver. 3: TOFF is the turn-off delay of power switch, QD, and its driver. START-UP CONSIDERATIONS When any PWM mode is used, the application hardware must use the proper external pull-up and/or pull-down resistors on the PWM output pins. Note: When the microcontroller is released from Reset, all of the I/O pins are in the High-Impedance state. The external circuits must keep the power switch devices in the OFF state until the microcontroller drives the I/O pins with the proper signal levels or activates the PWM output(s). The CCPxM<1:0> bits of the CCPxCON register allow the user to choose whether the PWM output signals are active-high or active-low for each pair of PWM output pins (PxA/PxC and PxB/PxD). The PWM output polarities must be selected before the PWM pin output drivers are enabled. Changing the polarity configuration while the PWM pin output drivers are enabled is not recommended since it may result in damage to the application circuits. The PxA, PxB, PxC and PxD output latches may not be in the proper states when the PWM module is initialized. Enabling the PWM pin output drivers at the same time as the Enhanced PWM modes may cause damage to the application circuit. The Enhanced PWM modes must be enabled in the proper Output mode and DS39957B-page 262 complete a full PWM cycle before enabling the PWM pin output drivers. The completion of a full PWM cycle is indicated by the TMR2IF or TMR4IF bit of the PIR1 or PIR5 register being set as the second PWM period begins. 19.4.4 ENHANCED PWM AUTO-SHUTDOWN MODE The PWM mode supports an Auto-Shutdown mode that will disable the PWM outputs when an external shutdown event occurs. Auto-Shutdown mode places the PWM output pins into a predetermined state. This mode is used to help prevent the PWM from damaging the application. The auto-shutdown sources are selected using the ECCPxAS<2:0> bits (ECCPxAS<6:4>). A shutdown event may be generated by: • A logic ‘0’ on the pin that is assigned the FLT0 input function • Comparator C1 • Comparator C2 • Setting the ECCPxASE bit in firmware A shutdown condition is indicated by the ECCPxASE (Auto-Shutdown Event Status) bit (ECCPxAS<7>). If the bit is a ‘0’, the PWM pins are operating normally. If the bit is a ‘1’, the PWM outputs are in the shutdown state. Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY When a shutdown event occurs, two things happen: Each pin pair may be placed into one of three states: • The ECCPxASE bit is set to ‘1’. The ECCPxASE will remain set until cleared in firmware or an auto-restart occurs. (See Section 19.4.5 “Auto-Restart Mode”.) • The enabled PWM pins are asynchronously placed in their shutdown states. The PWM output pins are grouped into pairs: PxA/PxC and PxB/PxD. The state of each pin pair is determined by the PSSxAC and PSSxBD bits (ECCPxAS<3:2> and <1:0>, respectively). • Drive logic ‘1’ • Drive logic ‘0’ • Tri-state (high-impedance) REGISTER 19-3: ECCPxAS: ECCPx AUTO-SHUTDOWN CONTROL REGISTER R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 ECCPxASE ECCPxAS2 ECCPxAS1 ECCPxAS0 PSSxAC1 PSSxAC0 PSSxBD1 PSSxBD0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 ECCPxASE: ECCP Auto-Shutdown Event Status bit 1 = A shutdown event has occurred; ECCP outputs are in a shutdown state 0 = ECCP outputs are operating bit 6-4 ECCPxAS<2:0>: ECCP Auto-Shutdown Source Select bits 000 = Auto-shutdown is disabled 001 = Comparator C1OUT output is high 010 = Comparator C2OUT output is high 011 = Either Comparator C1OUT or C2OUT is high 100 = VIL on FLT0 pin 101 = VIL on FLT0 pin or Comparator C1OUT output is high 110 = VIL on FLT0 pin or Comparator C2OUT output is high 111 = VIL on FLT0 pin, Comparator C1OUT or Comparator C2OUT is high bit 3-2 PSSxAC<1:0>: Pins PxA and PxC Shutdown State Control bits 00 = Drive the PxA and PxC pins to ‘0’ 01 = Drive the PxA and PxC pins to ‘1’ 1x = PxA and PxC pins tri-state bit 1-0 PSSxBD<1:0>: Pins PxB and PxD Shutdown State Control bits 00 = Drive the PxB and PxD pins to ‘0’ 01 = Drive the PxB and PxD pins to ‘1’ 1x = PxB and PxD pins tri-state Note: The auto-shutdown condition is a level-based signal, not an edge-based signal. As long as the level is present, the auto-shutdown will persist. Writing to the ECCPxASE bit is disabled while an auto-shutdown condition persists. Once the auto-shutdown condition has been removed and the PWM restarted (either through firmware or auto-restart), the PWM signal will always restart at the beginning of the next PWM period. 2010 Microchip Technology Inc. Preliminary DS39957B-page 263 PIC18F87K90 FAMILY FIGURE 19-12: PWM AUTO-SHUTDOWN WITH FIRMWARE RESTART (PxRSEN = 0) PWM Period Shutdown Event ECCPxASE bit PWM Activity Normal PWM Start of PWM Period 19.4.5 Shutdown Event Occurs AUTO-RESTART MODE The Enhanced PWM can be configured to automatically restart the PWM signal once the auto-shutdown condition has been removed. Auto-restart is enabled by setting the PxRSEN bit (ECCPxDEL<7>). Shutdown Event Clears ECCPxASE Cleared by Firmware PWM Resumes The module will wait until the next PWM period begins, however, before re-enabling the output pin. This behavior allows the auto-shutdown with auto-restart features to be used in applications based on current mode of PWM control. If auto-restart is enabled, the ECCPxASE bit will remain set as long as the auto-shutdown condition is active. When the auto-shutdown condition is removed, the ECCPxASE bit will be cleared via hardware and normal operation will resume. FIGURE 19-13: PWM AUTO-SHUTDOWN WITH AUTO-RESTART ENABLED (PxRSEN = 1) PWM Period Shutdown Event ECCPxASE bit PWM Activity Normal PWM Start of PWM Period DS39957B-page 264 Shutdown Event Occurs Preliminary Shutdown Event Clears PWM Resumes 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 19.4.6 PROGRAMMABLE DEAD-BAND DELAY MODE FIGURE 19-14: In half-bridge applications, where all power switches are modulated at the PWM frequency, the power switches normally require more time to turn off than to turn on. If both the upper and lower power switches are switched at the same time (one turned on and the other turned off), both switches may be on for a short period until one switch completely turns off. During this brief interval, a very high current (shoot-through current) will flow through both power switches, shorting the bridge supply. To avoid this potentially destructive shoot-through current from flowing during switching, turning on either of the power switches is normally delayed to allow the other switch to completely turn off. In Half-Bridge mode, a digitally programmable dead-band delay is available to avoid shoot-through current from destroying the bridge power switches. The delay occurs at the signal transition from the non-active state to the active state. For an illustration, see Figure 19-14. The lower seven bits of the associated ECCPxDEL register (Register 19-4) set the delay period in terms of microcontroller instruction cycles (TCY or 4 TOSC). FIGURE 19-15: EXAMPLE OF HALF-BRIDGE PWM OUTPUT Period Period Pulse Width (2) PxA td td PxB(2) (1) (1) (1) td = Dead-Band Delay Note 1: 2: At this time, the TMR2 register is equal to the PR2 register. Output signals are shown as active-high. EXAMPLE OF HALF-BRIDGE APPLICATIONS V+ Standard Half-Bridge Circuit (“Push-Pull”) FET Driver + V - PxA Load FET Driver + V - PxB V- 2010 Microchip Technology Inc. Preliminary DS39957B-page 265 PIC18F87K90 FAMILY REGISTER 19-4: ECCPxDEL: ENHANCED PWM CONTROL REGISTER R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 PxRSEN PxDC6 PxDC5 PxDC4 PxDC3 PxDC2 PxDC1 PxDC0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 PxRSEN: PWM Restart Enable bit 1 = Upon auto-shutdown, the ECCPxASE bit clears automatically once the shutdown event goes away; the PWM restarts automatically 0 = Upon auto-shutdown, ECCPxASE must be cleared by software to restart the PWM bit 6-0 PxDC<6:0>: PWM Delay Count bits PxDCn = Number of FOSC/4 (4 * TOSC) cycles between the scheduled time when a PWM signal should transition active and the actual time it does transition active. 19.4.7 PULSE STEERING MODE In Single Output mode, pulse steering allows any of the PWM pins to be the modulated signal. Additionally, the same PWM signal can simultaneously be available on multiple pins. Once the Single Output mode is selected (CCPxM<3:2> = 11 and PxM<1:0> = 00 of the CCPxCON register), the user firmware can bring out the same PWM signal to one, two, three or four output pins by setting the appropriate STR<D:A> bits (PSTRxCON<3:0>), as provided in Table 19-3. Note: While the PWM Steering mode is active, the CCPxM<1:0> bits (CCPxCON<1:0>) select the PWM output polarity for the Px<D:A> pins. The PWM auto-shutdown operation also applies to the PWM Steering mode, as described in Section 19.4.4 “Enhanced PWM Auto-shutdown mode”. An auto-shutdown event will only affect pins that have PWM outputs enabled. The associated TRIS bits must be set to output (‘0’) to enable the pin output driver in order to see the PWM signal on the pin. DS39957B-page 266 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY REGISTER 19-5: R/W-0 CMPL1 PSTRxCON: PULSE STEERING CONTROL(1) R/W-0 U-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-1 CMPL0 — STRSYNC STRD STRC STRB STRA bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7-6 CMPL<1:0>: Complementary Mode Output Assignment Steering Sync bits 00 = See STRD:STRA 01 = PA and PB are selected as the complementary output pair 10 = PA and PC are selected as the complementary output pair 11 = PA and PD are selected as the complementary output pair bit 5 Unimplemented: Read as ‘0’ bit 4 STRSYNC: Steering Sync bit 1 = Output steering update occurs on the next PWM period 0 = Output steering update occurs at the beginning of the instruction cycle boundary bit 3 STRD: Steering Enable bit D 1 = PxD pin has the PWM waveform with polarity control from CCPxM<1:0> 0 = PxD pin is assigned to a port pin bit 2 STRC: Steering Enable bit C 1 = PxC pin has the PWM waveform with polarity control from CCPxM<1:0> 0 = PxC pin is assigned to a port pin bit 1 STRB: Steering Enable bit B 1 = PxB pin has the PWM waveform with polarity control from CCPxM<1:0> 0 = PxB pin is assigned to a port pin bit 0 STRA: Steering Enable bit A 1 = PxA pin has the PWM waveform with polarity control from CCPxM<1:0> 0 = PxA pin is assigned to a port pin Note 1: The PWM Steering mode is available only when the CCPxCON register bits, CCPxM<3:2> = 11 and PxM<1:0> = 00. 2010 Microchip Technology Inc. Preliminary DS39957B-page 267 PIC18F87K90 FAMILY FIGURE 19-16: SIMPLIFIED STEERING BLOCK DIAGRAM 19.4.7.1 The STRSYNC bit of the PSTRxCON register gives the user two choices for when the steering event will happen. When the STRSYNC bit is ‘0’, the steering event will happen at the end of the instruction that writes to the PSTRxCON register. In this case, the output signal at the Px<D:A> pins may be an incomplete PWM waveform. This operation is useful when the user firmware needs to immediately remove a PWM signal from the pin. STRA PxA Signal CCPxM1 1 PORT Data 0 Output Pin TRIS STRB CCPxM0 1 PORT Data 0 Output Pin CCPxM1 1 PORT Data 0 TRIS CCPxM0 1 PORT Data 0 2: Figures 19-17 and 19-18 illustrate the timing diagrams of the PWM steering depending on the STRSYNC setting. Output Pin STRD Note 1: When the STRSYNC bit is ‘1’, the effective steering update will happen at the beginning of the next PWM period. In this case, steering on/off the PWM output will always produce a complete PWM waveform. TRIS STRC Steering Synchronization Output Pin TRIS Port outputs are configured as displayed when the CCPxCON register bits, PxM<1:0> = 00 and CCP1Mx<3:2> = 11. Single PWM output requires setting at least one of the STRx bits. FIGURE 19-17: EXAMPLE OF STEERING EVENT AT END OF INSTRUCTION (STRSYNC = 0) PWM Period PWM STRn P1<D:A> PORT Data PORT Data P1n = PWM FIGURE 19-18: EXAMPLE OF STEERING EVENT AT BEGINNING OF INSTRUCTION (STRSYNC = 1) PWM STRn P1<D:A> PORT Data PORT Data P1n = PWM DS39957B-page 268 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 19.4.8 OPERATION IN POWER-MANAGED MODES In Sleep mode, all clock sources are disabled. Timer2/4/6/8 will not increment and the state of the module will not change. If the ECCPx pin is driving a value, it will continue to drive that value. When the device wakes up, it will continue from this state. If Two-Speed Start-ups are enabled, the initial start-up frequency from HF-INTOSC and the postscaler may not be stable immediately. 19.4.9 EFFECTS OF A RESET Both Power-on Reset and subsequent Resets will force all ports to Input mode and the ECCP registers to their Reset states. This forces the ECCP module to reset to a state compatible with previous, non-enhanced CCP modules used on other PIC18 and PIC16 devices. In PRI_IDLE mode, the primary clock will continue to clock the ECCPx module without change. 19.4.8.1 Operation with Fail-Safe Clock Monitor (FSCM) If the Fail-Safe Clock Monitor (FSCM) is enabled, a clock failure will force the device into the power-managed RC_RUN mode and the OSCFIF bit of the PIR2/4/6/8 register will be set. The ECCPx will then be clocked from the internal oscillator clock source, which may have a different clock frequency than the primary clock. 2010 Microchip Technology Inc. Preliminary DS39957B-page 269 PIC18F87K90 FAMILY TABLE 19-4: File Name REGISTERS ASSOCIATED WITH ECCP1/2/3 MODULE AND TIMER1/2/3/4/6/8/10/12 Reset Values on Page: Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 INTCON GIE/GIEH PEIE/GIEL TMR0IE INT0IE RBIE TMR0IF INT0IF RBIF 73 RCON PIR3 IPEN TMR5GIF SBOREN LCDIF CM RC2IF RI TX2IF TO CTMUIF PD CCP2IF POR CCP1IF BOR RTCCIF 74 75 PIR4 PIE3 PIE4 IPR3 IPR4 TRISB CCP10IF(1) TMR5GIE CCP10IE(1) TMR5GIP CCP10IP(1) TRISB7 CCP9IF(1) LCDIE CCP9IE(1) LCDIP CCP9IP(1) TRISB6 CCP8IF RC2IE CCP8IE RC2IP CCP8IP TRISB5 CCP7IF TX2IE CCP7IE TX2IP CCP7IP TRISB4 CCP6IF CTMUIE CCP6IE CTMUIP CCP6IP TRISB3 CCP5IF CCP2IE CCP5IE CCP2IP CCP5IP TRISB2 CCP4IF CCP1IE CCP4IE CCP1IP CCP4IP TRISB1 CCP3IF RTCCIE CCP3IE RTCCIP CCP3IP TRISB0 75 75 75 75 75 76 TRISC5 TRISE5 TRISH5 TRISC4 TRISE4 TRISH4 TRISC3 TRISE3 TRISH3 TRISC2 TRISE2 TRISH2 TRISC1 TRISE1 TRISH1 TRISC0 TRISE0 TRISH0 76 76 76 74 74 74 75 75 80 79 79 79 79 74 80 79 79 79 79 RD16 T2CKPS1 TMR1ON T2CKPS0 74 74 RD16 TMR3CS1 TMR3CS0 T3CKPS1 T3CKPS0 SOSCEN T3SYNC — T4OUTPS3 T4OUTPS2 T4OUTPS1 T4OUTPS0 TMR4ON T4CKPS1 — T6OUTPS3 T6OUTPS2 T6OUTPS1 T6OUTPS0 TMR6ON T6CKPS1 — T8OUTPS3 T8OUTPS2 T8OUTPS1 T8OUTPS0 TMR8ON T8CKPS1 T10CON — T10OUTPS3 T10OUTPS2 T10OUTPS1 T10OUTPS0 TMR10ON T10CKPS1 T12CON — T12OUTPS3 T12OUTPS2 T12OUTPS1 T12OUTPS0 TMR12ON T12CKPS1 CCPR1H Capture/Compare/PWM Register1 High Byte CCPR1L Capture/Compare/PWM Register1 Low Byte CCPR2H Capture/Compare/PWM Register2 High Byte CCPR2L Capture/Compare/PWM Register2 Low Byte CCPR3H Capture/Compare/PWM Register3 High Byte CCPR3L Capture/Compare/PWM Register3 Low Byte CCP1CON P1M1 P1M0 DC1B1 DC1B0 CCP1M3 CCP1M2 CCP1M1 CCP2CON P2M1 P2M0 DC2B1 DC2B0 CCP2M3 CCP2M2 CCP2M1 CCP3CON P3M1 P3M0 DC3B1 DC3B0 CCP3M3 CCP3M2 CCP3M1 Note 1: Unimplemented on devices with a program memory of 32 Kbytes (PIC18FX5K90). 2: Unimplemented on PIC18F6XK90 devices. TMR3ON T4CKPS0 T6CKPS0 T8CKPS0 T10CKPS0 T12CKPS0 75 80 79 79 79 79 75 75 78 78 78 78 75 78 78 TRISC TRISE TRISH(2) TMR1H TMR1L TMR2 TMR3H TMR3L TMR4 TMR6 TMR8 TMR10 TMR12 PR2 PR4 PR6 PR8 PR10 PR12 T1CON T2CON TRISC7 TRISC6 TRISE7 TRISE6 TRISH7 TRISH6 Timer1 Register High Byte Timer1 Register Low Byte Timer2 Register Timer3 Register High Byte Timer3 Register Low Byte Timer4 Register Timer6 Register Timer8 Register TMR10 Register TMR10 Register Timer2 Period Register Timer4 Period Register Timer6 Period Register Timer8 Period Register Timer10 Period Register Timer12 Period Register TMR1CS1 — TMR1CS0 T1CKPS1 T1CKPS0 SOSCEN T1SYNC T2OUTPS3 T2OUTPS2 T2OUTPS1 T2OUTPS0 TMR2ON T3CON T4CON T6CON T8CON DS39957B-page 270 Preliminary CCP1M0 CCP2M0 CCP3M0 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 20.0 LIQUID CRYSTAL DISPLAY (LCD) DRIVER MODULE The LCD driver module supports: The Liquid Crystal Display (LCD) driver module generates the timing control to drive a static or multiplexed LCD panel. In the 80-pin devices (PIC18F8XK90), the module drives the panels of up to four commons and up to 48 segments and in the 64-pin devices (PIC18F6XK90), the module drives the panels of up to four commons and up to 33 segments. It also provides control of the LCD pixel data. • Direct driving of LCD panel • Three LCD clock sources with selectable prescaler • Up to four commons: - Static (One common) - 1/2 multiplex (two commons) - 1/3 multiplex (three commons) - 1/4 multiplex (four commons) • Up to 48 (in 80-pin devices), 32 (in 64-pin devices) segments • Static, 1/2 or 1/3 LCD bias • Internal resistors for bias voltage generation • Software contrast control for LCD using the internal biasing A simplified block diagram of the module is shown in Figure 20-1. FIGURE 20-1: LCD DRIVER MODULE BLOCK DIAGRAM Data Bus LCDDATAx Registers 24 x 8 (= 4 x 48) 192-to-48 MUX SE<47:0> To I/O Pads Timing Control LCDCON LCDPS COM<3:0> To I/O Pads LCDSEx FOSC/4 SOSC LF-INTOSC Oscillator 2010 Microchip Technology Inc. Clock Source Select and Prescaler Preliminary DS39957B-page 271 PIC18F87K90 FAMILY 20.1 LCD Registers The LCDCON register, shown in Register 20-1, controls the overall operation of the module. Once the module is configured, the LCDEN (LCDCON<7>) bit is used to enable or disable the LCD module. The LCD panel can also operate during Sleep by clearing the SLPEN (LCDCON<6>) bit. The LCD driver module has 32 registers: • • • • LCD Control Register (LCDCON) LCD Phase Register (LCDPS) LCD Reference Ladder Register (LCDRL) LCD Reference Voltage Control Register (LCDREF) • Six LCD Segment Enable Registers (LCDSE5:LCDSE0) • 24 LCD Data Registers (LCDDATA23:LCDDATA0) REGISTER 20-1: R/W-0 LCDCON: LCD CONTROL REGISTER R/W-0 LCDEN The LCDPS register, shown in Register 20-2, configures the LCD clock source prescaler and the type of waveform, Type-A or Type-B. For details on these features, see Section 20.2 “LCD Clock Source Selection”, Section 20.3 “LCD Bias Types” and Section 20.8 “LCD Waveform Generation”. SLPEN R/C-0 U-0 R/W-0 R/W-0 R/W-0 R/W-0 WERR — CS1 CS0 LMUX1 LMUX0 bit 7 bit 0 Legend: C = Clearable bit R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 LCDEN: LCD Driver Enable bit 1 = LCD driver module is enabled 0 = LCD driver module is disabled bit 6 SLPEN: LCD Driver Enable in Sleep mode bit 1 = LCD driver module is disabled in Sleep mode 0 = LCD driver module is enabled in Sleep mode bit 5 WERR: LCD Write Failed Error bit 1 = LCDDATAx register is written while WA (LCDPS<4>) = 0 (must be cleared in software) 0 = No LCD write error bit 4 Unimplemented: Read as ‘0’ bit 3-2 CS<1:0>: Clock Source Select bits 00 = (FOSC/4)/8192 01 = SOSC oscillator/32 1x = INTRC (31.25 kHz)/32 bit 1-0 LMUX<1:0>: Commons Select bits LMUX<1:0> DS39957B-page 272 Maximum Maximum Number of Pixels Number of Pixels (PIC18F6X90) (PIC18F8X90) Multiplex Bias 00 Static (COM0) 33 48 Static 01 1/2 (COM<1:0>) 66 96 1/2 or 1/3 10 1/3 (COM<2:0>) 99 144 1/2 or 1/3 11 1/4 (COM<3:0>) 132 192 1/3 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY REGISTER 20-2: LCDPS: LCD PHASE REGISTER R/W-0 R/W-0 R-0 R-0 R/W-0 R/W-0 R/W-0 R/W-0 WFT BIASMD LCDA WA LP3 LP2 LP1 LP0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7 WFT: Waveform Type Select bit 1 = Type-B waveform (phase changes on each frame boundary) 0 = Type-A waveform (phase changes within each common type) bit 6 BIASMD: Bias Mode Select bit When LMUX<1:0> = 00: 0 = Static Bias mode (do not set this bit to ‘1’) When LMUX<1:0> = 01: 1 = 1/2 Bias mode 0 = 1/3 Bias mode When LMUX<1:0> = 10: 1 = 1/2 Bias mode 0 = 1/3 Bias mode When LMUX<1:0> = 11: 0 = 1/3 Bias mode (do not set this bit to ‘1’) bit 5 LCDA: LCD Active Status bit 1 = LCD driver module is active 0 = LCD driver module is inactive bit 4 WA: LCD Write Allow Status bit 1 = Write into the LCDDATAx registers is allowed 0 = Write into the LCDDATAx registers is not allowed bit 3-0 LP<3:0>: LCD Prescaler Select bits 1111 = 1:16 1110 = 1:15 1101 = 1:14 1100 = 1:13 1011 = 1:12 1010 = 1:11 1001 = 1:10 1000 = 1:9 0111 = 1:8 0110 = 1:7 0101 = 1:6 0100 = 1:5 0011 = 1:4 0010 = 1:3 0001 = 1:2 0000 = 1:1 2010 Microchip Technology Inc. Preliminary x = Bit is unknown DS39957B-page 273 PIC18F87K90 FAMILY REGISTER 20-3: LCDREF: LCD REFERENCE VOLTAGE CONTROL REGISTER R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 LCDIRE LCDIRS LCDCST2 LCDCST1 LCDCST0 VLCD3PE VLCD2PE VLCD1PE bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 LCDIRE: LCD Internal Reference Enable bit 1 = Internal LCD reference is enabled and connected to the internal contrast control circuit 0 = Internal LCD reference is disabled bit 6 LCDIRS: LCD Internal Reference Source bit If LCDIRE = 1: 1 = Internal LCD contrast control is powered by VDDCORE (3.3V) voltage 0 = Internal LCD contrast control is powered by VDD If LCDIRE = 0: Internal LCD contrast control is unconnected. LCD band gap buffer is disabled. bit 5-3 LCDCST<2:0>: LCD Contrast Control bits Selects the resistance of the LCD contrast control resistor ladder: 111 = Resistor ladder is at maximum resistance (minimum contrast) 110 = Resistor ladder is at 6/7th of maximum resistance 101 = Resistor ladder is at 5/7th of maximum resistance 100 = Resistor ladder is at 4/7th of maximum resistance 011 = Resistor ladder is at 3/7th of maximum resistance 010 = Resistor ladder is at 2/7th of maximum resistance 001 = Resistor ladder is at 1/7th of maximum resistance 000 = Minimum resistance (maximum contrast); resistor ladder is shorted bit 2 VLCD3PE: Bias 3 Pin Enable bit 1 = Bias 3 level is connected to the external pin, LCDBIAS3 0 = Bias 3 level is internal (internal resistor ladder) bit 1 VLCD2PE: Bias 2 Pin Enable bit 1 = Bias 2 level is connected to the external pin, LCDBIAS2 0 = Bias 2 level is internal (internal resistor ladder) bit 0 VLCD1PE: Bias 1 Pin Enable bit 1 = Bias 1 level is connected to the external pin, LCDBIAS1 0 = Bias 1 level is internal (internal resistor ladder) DS39957B-page 274 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY REGISTER 20-4: R/W-0 LCDRL: LCD REFERENCE LADDER CONTROL REGISTER R/W-0 LRLAP1 LRLAP0 R/W-0 LRLBP1 R/W-0 U-0 R/W-0 R/W-0 R/W-0 LRLBP0 —(1) LRLAT2 LRLAT1 LRLAT0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7-6 LRLAP<1:0>: LCD Reference Ladder A Time Power Control bits During Time Interval A: 11 = Internal LCD reference ladder is powered in High-Power mode 10 = Internal LCD reference ladder is powered in Medium Power mode 01 = Internal LCD reference ladder is powered in Low-Power mode 00 = Internal LCD reference ladder is powered down and unconnected bit 5-4 LRLBP<1:0>: LCD Reference Ladder B Time Power Control bits During Time Interval B: 11 = Internal LCD reference ladder is powered in High-Power mode 10 = Internal LCD reference ladder is powered in Medium Power mode 01 = Internal LCD reference ladder is powered in Low-Power mode 00 = Internal LCD reference ladder is powered down and unconnected bit 3 Unimplemented: Read as ‘0’(1) bit 2-0 LRLAT<2:0>: LCD Reference Ladder A Time Interval Control bits Sets the number of 32 clock counts when the A Time Interval Power mode is active. For Type-A Waveforms (WFT = 0): 000 = Internal LCD reference ladder is always in B Power mode 001 = Internal LCD reference ladder is in A Power mode for 1 clock and B Power mode for 15 clocks 010 = Internal LCD reference ladder is in A Power mode for 2 clocks and B Power mode for 14 clocks 011 = Internal LCD reference ladder is in A Power mode for 3 clocks and B Power mode for 13 clocks 100 = Internal LCD reference ladder is in A Power mode for 4 clocks and B Power mode for 12 clocks 101 = Internal LCD reference ladder is in A Power mode for 5 clocks and B Power mode for 11 clocks 110 = Internal LCD reference ladder is in A Power mode for 6 clocks and B Power mode for 10 clocks 111 = Internal LCD reference ladder is in A Power mode for 7 clocks and B Power mode for 9 clocks For Type-B Waveforms (WFT = 1): 000 = Internal LCD reference ladder is always in B Power mode 001 = Internal LCD reference ladder is in A Power mode for 1 clock and B Power mode for 31 clocks 010 = Internal LCD reference ladder is in A Power mode for 2 clocks and B Power mode for 30 clocks 011 = Internal LCD reference ladder is in A Power mode for 3 clocks and B Power mode for 29 clocks 100 = Internal LCD reference ladder is in A Power mode for 4 clocks and B Power mode for 28 clocks 101 = Internal LCD reference ladder is in A Power mode for 5 clocks and B Power mode for 27 clocks 110 = Internal LCD reference ladder is in A Power mode for 6 clocks and B Power mode for 26 clocks 111 = Internal LCD reference ladder is in A Power mode for 7 clocks and B Power mode for 25 clocks Note 1: LCDRL<3> should be maintained as ‘0’. 2010 Microchip Technology Inc. Preliminary DS39957B-page 275 PIC18F87K90 FAMILY The LCDSE5:LCDSE0 registers configure the functions of the port pins. Setting the segment enable bit for a particular segment configures that pin as an LCD driver. There are six LCD Segment Enable registers, as shown in Table 20-1. The prototype LCDSEx register is shown in Register 20-5. TABLE 20-1: LCDSE REGISTERS AND ASSOCIATED SEGMENTS The LCDSE5:LCDSE4 registers are not implemented in PIC18F6XK90 devices. Once the module is initialized for the LCD panel, the individual bits of the LCDDATA23:LCDDATA0 registers are cleared or set to represent a clear or dark pixel, respectively. Specific sets of LCDDATA registers are used with specific segments and common signals. Each bit represents a unique combination of a specific segment connected to a specific common. Register Segments LCDSE0 7:0 (RD<7:0>) LCDSE1 15:8 (RA<5:4>, RC2, RC5, RB<4:1>) LCDSE2 23:16 (RF<5:1>, RA1, RC<4:3>) LCDSE3 31:24 (RE7, RB0, RB5, RC<7:6>, RG4, RF<7:6>) LCDSE4 39:32 (RJ<4:7>, RJ<3:1>, RC1) LCDSE5 47:40 (RH<0:3>, RH<7:4>) REGISTER 20-5: Note: Individual LCDDATA bits are named by the convention, “SxxCy”, with “xx” as the segment number and “y” as the common number. The relationship is summarized in Table 20-2. The prototype LCDDATAx register is shown in Register 20-6. Note: In PIC18F6XK90 devices, writing into the registers, LCDDATA4, LCDDATA5, LCDDATA10, LCDDATA11, LCDDATA16, LCDDATA17, LCDDATA22 and LCDDATA23, will not affect the status of any pixel. These registers can be used as general purpose registers. LCDSEx: LCD SEGMENTx ENABLE REGISTER R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 SE(n + 7) SE(n + 6) SE(n + 5) SE(n + 4) SE(n + 3) SE(n + 2) SE(n + 1) SE(n) bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7-0 x = Bit is unknown SE(n + 7):SE(n): Segment Enable bits For LCDSE0: n = 0 For LCDSE1: n = 8 For LCDSE2: n = 16 For LCDSE3: n = 24 For LCDSE4: n = 32 For LCDSE5: n = 40 1 = Segment function of the pin is enabled, digital I/O is disabled 0 = I/O function of the pin is enabled DS39957B-page 276 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY TABLE 20-2: LCDDATA REGISTERS AND BITS FOR SEGMENT AND COM COMBINATIONS COM Lines Segments 0 through 7 8 through 15 16 through 23 24 through 31 32 through 39 40 through 47 Note 1: 2: 0 1 2 3 LCDDATA0 LCDDATA6 LCDDATA12 LCDDATA18 S00C0:S07C0 S00C1:S07C1 S00C2:S07C2 S00C3:S07C3 LCDDATA1 LCDDATA7 LCDDATA13 LCDDATA19 S08C0:S15C0 S08C1:S15C1 S08C2:S15C2 S08C0:S15C3 LCDDATA2 LCDDATA8 LCDDATA14 LCDDATA20 S16C0:S23C0 S16C1:S23C1 S16C2:S23C2 S16C3:S23C3 LCDDATA3 LCDDATA9 LCDDATA15 LCDDATA21 S24C0:S31C0 S24C1:S31C1 S24C2:S31C2 S24C3:S31C3 LCDDATA4(1) LCDDATA10(1) LCDDATA16(1) LCDDATA22(1) S32C0:S39C0 S32C1:S39C1 S32C2:S39C2 S32C3:S39C3 LCDDATA5(2) LCDDATA11(2) LCDDATA17(2) LCDDATA23(2) S40C0:S47C0 S40C1:S47C1 S40C2:S47C2 S40C3:S47C3 Bits<7:1> of these registers are not implemented in PIC18F6XK90 devices. Bit 0 of these registers (SEG32Cy) is always implemented. These registers are not implemented in PIC18F6XK90 devices. REGISTER 20-6: LCDDATAx: LCD DATAx REGISTER R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 S(n + 7)Cy S(n + 6)Cy S(n + 5)Cy S(n + 4)Cy S(n + 3)Cy S(n + 2)Cy S(n + 1)Cy S(n)Cy bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7-0 x = Bit is unknown S(n + 7)Cy:S(n)Cy: Pixel On bits For registers, LCDDATA0 through LCDDATA5: n = (8x), y = 0 For registers, LCDDATA6 through LCDDATA11: n = (8(x – 6)), y = 1 For registers, LCDDATA12 through LCDDATA17: n = (8(x – 12)), y = 2 For registers, LCDDATA18 through LCDDATA23: n = (8(x – 18)), y = 3 1 = Pixel on (dark) 0 = Pixel off (clear) 2010 Microchip Technology Inc. Preliminary DS39957B-page 277 PIC18F87K90 FAMILY LCD Clock Source Selection The LCD driver module has three possible clock sources: • (FOSC/4)/8192 • SOSC Clock/32 • INTRC/32 The second clock source is the SOSC oscillator/32. This also outputs about 1 kHz when a 32.768 kHz crystal is used with the SOSC oscillator. To use the SOSC oscillator as a clock source, set the SOSCEN (T1CON<3>) bit. 20.2.1 LCD PRESCALER A 16-bit counter is available as a prescaler for the LCD clock. The prescaler is not directly readable or writable. Its value is set by the LP<3:0> bits (LCDPS<3:0>) that determines the prescaler assignment and prescale ratio. Selectable prescale values are from 1:1 through 1:32,768, in power-of-2 increments. SOSC 32 kHz Crystal Oscillator LF-INTOSC Oscillator Nom FRC = 31.25 kHz COM3 COM0 LCD CLOCK GENERATION System Clock (FOSC/4) ÷8192 ÷32 ÷32 CS<1:0> (LCDCON<3:2>) DS39957B-page 278 The second and third clock sources may be used to continue running the LCD while the processor is in Sleep. These clock sources are selected through the bits CS<1:0> (LCDCON<3:2>). The first clock source is the system clock divided by 8,192 ((FOSC/4)/8192). This divider ratio is chosen to provide about 1 kHz output when the system clock is 8 MHz. The divider is not programmable. Instead, the LCD prescaler bits, LCDPS<3:0>, are used to set the LCD frame clock rate. FIGURE 20-2: The third clock source is a 31.25 kHz internal RC oscillator/32 that provides approximately 1 kHz output. COM1 COM2 20.2 ÷4 STAT ÷2 DUP 4-Bit Prog Prescaler ÷1, 2, 3, 4 Ring Counter TRIP QUAD LP<3:0> (LCDPS<3:0>) LMUX<1:0> (LCDCON<1:0>) LMUX<1:0> (LCDCON<1:0>) Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 20.3 LCD Bias Types The LCD module can be configured in one of three bias types: • Static bias (two voltage levels: VSS and VDD) • 1/2 bias (three voltage levels: VSS, 1/2 VDD and VDD) • 1/3 bias (four voltage levels: VSS, 1/3 VDD, 2/3 VDD and VDD) 20.3.1 LCD bias voltages can be generated with an internal or external resistor ladder. The internal resistor ladder eliminates the external solution’s use of up to three pins. FIGURE 20-3: If the internal reference ladder is used to generate bias voltages, it also can provide software contrast control (using LCDCST<2:0>). An external resistor ladder can not do this. EXTERNAL RESISTOR BIASING The external resistor ladder should be connected to the VLCD1 pin (Bias 1), VLCD2 pin (Bias 2), VLCD3 pin (Bias 3) and VSS. The VLCD3 pin is used to set the highest voltage to the LCD glass and can be connected to VDD or a lower voltage. Figure 20-3 shows the proper way to connect the resistor ladder to the Bias pins. LCD BIAS EXTERNAL RESISTOR LADDER CONNECTION DIAGRAM Static Bias VLCD3 To VLCD2 LCD VLCD1 Driver VLCD0 LCD Bias 3 LCD Bias 2 LCD Bias 1 AVSS AVSS VLCD0 AVSS VLCD1 — 1/2 AVDD 1/3 AVDD VLCD2 — 1/2 AVDD 2/3 AVDD VLCD3 AVDD AVDD AVDD Connections for External R-ladder Static Bias AVDD* AVDD* 1/2 Bias 1/3 Bias 10 k* 1/2 Bias 10 k* AVSS AVDD* 10 k* 10 k* 1/3 Bias 10 k* AVSS * These values are provided for design guidance only and should be optimized for the application by the designer. 2010 Microchip Technology Inc. Preliminary DS39957B-page 279 PIC18F87K90 FAMILY 20.3.2 INTERNAL RESISTOR BIASING This mode does not use external resistors, but rather internal resistor ladders that are configured to generate the bias voltage. The internal reference ladder actually consists of three separate ladders. Disabling the internal reference ladder disconnects all of the ladders, allowing external voltages to be supplied. Table 20-3 shows the total resistance of each of the ladders. Figure 20-4 shows the internal resister ladder connections. When the internal resistor ladder is selected, the bias voltage can either be from VDD or from VDDCORE, depending on the LCDIRS setting. TABLE 20-3: Depending on the total resistance of the resistor ladders, the biasing can be classified as low, medium or high power. FIGURE 20-4: INTERNAL RESISTANCE LADDER POWER MODES Power Mode Nominal Resistance of Entire Ladder Low 3 M Medium 300 k 10 A High 30 k 100 A IDD 1 A LCD BIAS INTERNAL RESISTOR LADDER CONNECTION DIAGRAM VVDD DD DDCORE 3x V Band Gap LCDIRS LCDIRE LCDCST<2:0> VLCD3PE LCDBIAS3 VLCD2PE LCDBIAS2 VLCD1PE LCDBIAS1 Low Resistor Ladder Medium Resistor Ladder High Resistor Ladder A Power Mode B Power Mode LRLAT<2:0> LRLAP<1:0> DS39957B-page 280 LRLBP<1:0> Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 20.3.2.1 There are two power modes designated as “Mode A” and “Mode B”. Mode A is set by the bits, LRLAP<1:0> and Mode B by LRLB<1:0>. The resistor ladder to use for Modes A and B are selected by the bits, LRLAP<1:0> and LRLBP<1:0>, respectively As an LCD segment is electrically only a capacitor, current is drawn only during the interval when the voltage is switching. To minimize total device current, the LCD reference ladder can be operated in a different power mode for the transition portion of the duration. This is controlled by the LCDRL register. Each ladder has a matching contrast control ladder, tuned to the nominal resistance of the reference ladder. This contrast control resistor can be controlled by LCDREF<5:3> (LCDCST<2:0>). Disabling the internal reference ladder results in all of the ladders being disconnected, allowing external voltages to be supplied. Mode A Power mode is active for a programmable time, beginning at the time when the LCD segment waveform is transitioning. The LCDRL<2:1> (LRLAT<2:0>) bits select how long, or if the Mode A is active. Mode B Power mode is active for the remaining time before the segments or commons change again. To get additional current in High-Power mode, when LCDRL<7:6> (LRLAP<1:0>) = 11, both the medium and high-power resistor ladders are activated. As shown in Figure 20-5, there are 32 counts in a single segment time. Type-A can be chosen during the time when the wave form is in transition. Type-B can be used when the clock is stable or not in transition. Whenever the LCD module is inactive (LCDA (LCDPS<5>) = 0), the reference ladder will be turned off. FIGURE 20-5: Automatic Power Mode Switching By using this feature of automatic power switching, using Type-A/Type-B, the power consumption can be optimized for a given contrast. LCD REFERENCE LADDER POWER MODE SWITCHING DIAGRAM Single Segment Time lcd_32x_clk cnt<4:0> 'H00 'H01 'H02 'H03 'H04 'H05 'H06 'H07 'H1E 'H1F 'H00 'H01 lcd_clk 'H3 LRLAT<2:0> Segment Data LRLAT<2:0> Power Mode Power Mode A 2010 Microchip Technology Inc. Power Mode B Preliminary Mode A DS39957B-page 281 PIC18F87K90 FAMILY 20.3.2.2 Contrast Control The LCD contrast control circuit consists of a 7-tap resistor ladder, controlled by the LCDCST bits (see Figure 20-6.). FIGURE 20-6: INTERNAL REFERENCE AND CONTRAST CONTROL BLOCK DIAGRAM 7 Stages VDD R R R R Analog MUX 7 0 To Top of Reference Ladder LCDCST<2:0> 3 Internal Reference DS39957B-page 282 Contrast Control Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 20.3.2.3 Internal Reference Under firmware control, an internal reference for the LCD bias voltages can be enabled. When enabled, the source of this voltage can be VDD. When no internal reference is selected, the LCD contrast control circuit is disabled and LCD bias must be provided externally. Whenever the LCD module is inactive (LCDA = 0), the internal reference will be turned off. 20.3.2.4 Each VLCD pin has an independent control in the LCDREF register, allowing access to any or all of the LCD bias signals. This architecture allows for maximum flexibility in different applications. The VLCDx pins could be used to add capacitors to the internal reference ladder for increasing the drive capacity. For applications where the internal contrast control is insufficient, the firmware can choose to enable only the VLCD3 pin, allowing an external contrast control circuit to use the internal reference divider. LCD Multiplex Types The LCD driver module can be configured into four multiplex types: • • • • If the pin is a digital I/O, the corresponding TRIS bit controls the data direction. If the pin is a COM drive, the TRIS setting of that pin is overridden. Note: On a Power-on Reset, the LMUX<1:0> bits are ‘00’. TABLE 20-4: VLCDx Pins The VLCD3, VLCD2 and VLCD1 pins provide the ability for an external LCD bias network to be used instead of the internal ladder. Use of the VLCDx pins does not prevent use of the internal ladder. 20.4 The LMUX<1:0> setting (LCDCON<1:0>) decides the function of the PORTE<6:4> bits. (For details, see Table 20-4.) Static (only COM0 used) 1/2 multiplex (COM0 and COM1 are used) 1/3 multiplex (COM0, COM1 and COM2 are used) 1/4 multiplex (COM0, COM1, COM2 and COM3 are used) PORTE<6:4> FUNCTION LMUX<1:0> PORTE<6> PORTE<5> 00 Digital I/O Digital I/O Digital I/O 01 Digital I/O Digital I/O COM1 Driver 10 11 20.5 Digital I/O PORTE<4> COM2 Driver COM1 Driver COM3 Driver COM2 Driver COM1 Driver Segment Enables The LCDSEx registers are used to select the pin function for each segment pin. The selection allows each pin to operate as either an LCD segment driver or a digital only pin. To configure the pin as a segment pin, the corresponding bits in the LCDSEx registers must be set to ‘1’. If the pin is a digital I/O, the corresponding TRIS bit controls the data direction. Any bit set in the LCDSEx registers overrides any bit settings in the corresponding TRIS register. Note: 20.6 On a Power-on Reset, these pins are configured as digital I/O. Pixel Control The LCDDATAx registers contain bits that define the state of each pixel. Each bit defines one unique pixel. Table 20-2 shows the correlation of each bit in the LCDDATAx registers to the respective common and segment signals. Any LCD pixel location not being used for display can be used as general purpose RAM. 2010 Microchip Technology Inc. Preliminary DS39957B-page 283 PIC18F87K90 FAMILY 20.7 LCD Frame Frequency 20.8 The rate at which the COM and SEG outputs change is called the LCD frame frequency. TABLE 20-5: FRAME FREQUENCY FORMULAS Multiplex Frame Frequency = Static Clock Source/(4 x 1 x (LP<3:0> + 1)) 1/2 Clock Source/(2 x 2 x (LP<3:0> + 1)) 1/3 Clock Source/(1 x 3 x (LP<3:0> + 1)) 1/4 Clock Source/(1 x 4 x (LP<3:0> + 1)) Note: Clock source is (FOSC/4)/8192, Timer1 Osc/32 or INTRC/32. TABLE 20-6: APPROXIMATE FRAME FREQUENCY (IN Hz) USING FOSC AT 32 MHz, TIMER1 AT 32.768 kHz OR INTRC OSC LP<3:0> Static 1/2 1/3 1/4 1 125 125 167 125 2 83 83 111 83 3 62 62 83 62 4 50 50 67 50 5 42 42 56 42 6 36 36 48 36 7 31 31 42 31 LCD Waveform Generation LCD waveform generation is based on the philosophy that the net AC voltage across the dark pixel should be maximized and the net AC voltage across the clear pixel should be minimized. The net DC voltage across any pixel should be zero. The COM signal represents the time slice for each common, while the SEG contains the pixel data. The pixel signal (COM-SEG) will have no DC component and can take only one of the two rms values. The higher rms value will create a dark pixel and a lower rms value will create a clear pixel. As the number of commons increases, the delta between the two rms values decreases. The delta represents the maximum contrast that the display can have. The LCDs can be driven by two types of waveforms: Type-A and Type-B. In a Type-A waveform, the phase changes within each common type, whereas a Type-B waveform’s phase changes on each frame boundary. Thus, Type-A waveforms maintain 0 VDC over a single frame, whereas Type-B waveforms take two frames. Note 1: If Sleep has to be executed with LCD Sleep enabled (SLPEN (LCDCON<6>) = 1), care must be taken to execute Sleep only when VDC on all the pixels is ‘0’. 2: When the LCD clock source is (FOSC/4)/ 8192, if Sleep is executed irrespective of the LCDCON<SLPEN> setting, the LCD goes into Sleep. Thus, take care to see that VDC on all pixels is ‘0’ when Sleep is executed. Figure 20-7 through Figure 20-17 provide waveforms for static, half-multiplex, one-third multiplex and quarter multiplex drives for Type-A and Type-B waveforms. DS39957B-page 284 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY FIGURE 20-7: TYPE-A/TYPE-B WAVEFORMS IN STATIC DRIVE V1 COM0 V0 COM0 V1 SEG0 V0 V1 SEG1 SEG0 SEG2 SEG7 SEG6 SEG5 SEG4 SEG3 SEG1 V0 V1 V0 COM0-SEG0 -V1 COM0-SEG1 V0 1 Frame 2010 Microchip Technology Inc. Preliminary DS39957B-page 285 PIC18F87K90 FAMILY FIGURE 20-8: TYPE-A WAVEFORMS IN 1/2 MUX, 1/2 BIAS DRIVE V2 COM0 V1 V0 COM1 V2 COM0 COM1 V1 V0 V2 V1 SEG0 V0 SEG0 SEG1 SEG2 SEG3 V2 V1 SEG1 V0 V2 V1 V0 COM0-SEG0 -V1 -V2 V2 V1 V0 COM0-SEG1 -V1 -V2 1 Frame DS39957B-page 286 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY FIGURE 20-9: TYPE-B WAVEFORMS IN 1/2 MUX, 1/2 BIAS DRIVE V2 V1 COM0 COM1 V0 COM0 V2 COM1 V1 V0 V2 SEG0 V1 SEG0 SEG1 SEG2 SEG3 V0 V2 SEG1 V1 V0 V2 V1 V0 COM0-SEG0 -V1 -V2 V2 V1 V0 COM0-SEG1 -V1 -V2 2 Frames 2010 Microchip Technology Inc. Preliminary DS39957B-page 287 PIC18F87K90 FAMILY FIGURE 20-10: TYPE-A WAVEFORMS IN 1/2 MUX, 1/3 BIAS DRIVE V3 V2 COM0 V1 COM1 V0 V3 COM0 V2 COM1 V1 V0 V3 V2 SEG0 V1 V0 SEG0 SEG1 SEG2 SEG3 V3 V2 SEG1 V1 V0 V3 V2 V1 V0 COM0-SEG0 -V1 -V2 -V3 V3 V2 V1 V0 COM0-SEG1 -V1 -V2 1 Frame DS39957B-page 288 Preliminary -V3 2010 Microchip Technology Inc. PIC18F87K90 FAMILY FIGURE 20-11: TYPE-B WAVEFORMS IN 1/2 MUX, 1/3 BIAS DRIVE V3 V2 COM0 V1 COM1 V0 V3 COM0 V2 COM1 V1 V0 V3 V2 SEG0 V1 V0 SEG0 SEG1 SEG2 SEG3 V3 V2 SEG1 V1 V0 V3 V2 V1 V0 COM0-SEG0 -V1 -V2 -V3 V3 V2 V1 V0 COM0-SEG1 -V1 -V2 2 Frames 2010 Microchip Technology Inc. Preliminary -V3 DS39957B-page 289 PIC18F87K90 FAMILY FIGURE 20-12: TYPE-A WAVEFORMS IN 1/3 MUX, 1/2 BIAS DRIVE V2 COM0 V1 V0 COM2 V2 COM1 V1 V0 COM1 COM0 V2 COM2 V1 V0 V2 SEG0 SEG2 V1 SEG0 SEG1 SEG2 V0 V2 SEG1 V1 V0 V2 V1 V0 COM0-SEG0 -V1 -V2 V2 V1 V0 COM0-SEG1 -V1 -V2 1 Frame DS39957B-page 290 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY FIGURE 20-13: TYPE-B WAVEFORMS IN 1/3 MUX, 1/2 BIAS DRIVE V2 COM0 V1 V0 COM2 V2 COM1 V1 COM1 V0 COM0 V2 COM2 V1 V0 V2 V1 V0 SEG0 SEG1 SEG2 SEG0 V2 SEG1 V1 V0 V2 V1 V0 COM0-SEG0 -V1 -V2 V2 V1 V0 COM0-SEG1 -V1 -V2 2 Frames 2010 Microchip Technology Inc. Preliminary DS39957B-page 291 PIC18F87K90 FAMILY FIGURE 20-14: TYPE-A WAVEFORMS IN 1/3 MUX, 1/3 BIAS DRIVE V3 V2 COM0 V1 V0 V3 COM2 V2 COM1 V1 COM1 V0 COM0 V3 V2 COM2 V1 V0 V3 V2 V1 V0 SEG0 SEG1 SEG2 SEG0 SEG2 V3 V2 SEG1 V1 V0 V3 V2 V1 V0 COM0-SEG0 -V1 -V2 -V3 V3 V2 V1 V0 COM0-SEG1 -V1 -V2 -V3 1 Frame DS39957B-page 292 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY FIGURE 20-15: TYPE-B WAVEFORMS IN 1/3 MUX, 1/3 BIAS DRIVE V3 V2 COM0 V1 V0 V3 COM2 V2 COM1 V1 COM1 V0 COM0 V3 V2 COM2 V1 V0 V3 V2 V1 V0 SEG0 SEG1 SEG2 SEG0 V3 V2 SEG1 V1 V0 V3 V2 V1 V0 COM0-SEG0 -V1 -V2 -V3 V3 V2 V1 V0 COM0-SEG1 -V1 -V2 -V3 2 Frames 2010 Microchip Technology Inc. Preliminary DS39957B-page 293 PIC18F87K90 FAMILY FIGURE 20-16: TYPE-A WAVEFORMS IN 1/4 MUX, 1/3 BIAS DRIVE COM3 COM2 COM1 COM0 V3 V2 V1 V0 COM1 V3 V2 V1 V0 COM2 V3 V2 V1 V0 COM3 V3 V2 V1 V0 SEG0 V3 V2 V1 V0 SEG1 V3 V2 V1 V0 COM0-SEG0 V3 V2 V1 V0 -V1 -V2 -V3 COM0-SEG1 V3 V2 V1 V0 -V1 -V2 -V3 SEG0 SEG1 COM0 1 Frame DS39957B-page 294 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY FIGURE 20-17: TYPE-B WAVEFORMS IN 1/4 MUX, 1/3 BIAS DRIVE COM3 COM2 COM1 COM0 V3 V2 V1 V0 COM1 V3 V2 V1 V0 COM2 V3 V2 V1 V0 COM3 V3 V2 V1 V0 SEG0 V3 V2 V1 V0 SEG1 V3 V2 V1 V0 COM0-SEG0 V3 V2 V1 V0 -V1 -V2 -V3 COM0-SEG1 V3 V2 V1 V0 -V1 -V2 -V3 SEG0 SEG1 COM0 2 Frames 2010 Microchip Technology Inc. Preliminary DS39957B-page 295 PIC18F87K90 FAMILY 20.9 LCD Interrupts When the LCD driver is running with Type-B waveforms and the LMUX<1:0> bits are not equal to ‘00’, there are some additional issues. The LCD timing generation provides an interrupt that defines the LCD frame timing. This interrupt can be used to coordinate the writing of the pixel data with the start of a new frame, which produces a visually crisp transition of the image. Since the DC voltage on the pixel takes two frames to maintain 0V, the pixel data must not change between subsequent frames. If the pixel data were allowed to change, the waveform for the odd frames would not necessarily be the complement of the waveform generated in the even frames and a DC component would be introduced into the panel. This interrupt can also be used to synchronize external events to the LCD. For example, the interface to an external segment driver can be synchronized for segment data updates to the LCD frame. Because of this, using Type-B waveforms requires synchronizing the LCD pixel updates to occur within a subframe after the frame interrupt. A new frame is defined as beginning at the leading edge of the COM0 common signal. The interrupt will be set immediately after the LCD controller completes accessing all pixel data required for a frame. This will occur at a fixed interval before the frame boundary (TFINT), as shown in Figure 20-18. To correctly sequence writing in Type-B, the interrupt only occurs on complete phase intervals. If the user attempts to write when the write is disabled, the WERR bit (LCDCON<5>) is set. The LCD controller will begin to access data for the next frame within the interval from the interrupt to when the controller begins accessing data after the interrupt (TFWR). New data must be written within TFWR, as this is when the LCD controller will begin to access the data for the next frame. FIGURE 20-18: Note: The interrupt is not generated when the Type-A waveform is selected and when the Type-B with no multiplex (static) is selected. EXAMPLE WAVEFORMS AND INTERRUPT TIMING IN QUARTER DUTY CYCLE DRIVE LCD Interrupt Occurs Controller Accesses Next Frame Data COM0 V3 V2 V1 V0 COM1 V3 V2 V1 V0 COM2 V3 V2 V1 V0 V3 V2 V1 V0 COM3 2 Frames TFINT Frame Boundary Frame Boundary TFWR Frame Boundary TFWR = TFRAME/2*(LMUX<1:0> + 1) + TCY/2 TFINT = (TFWR/2 – (2 TCY + 40 ns)) minimum = 1.5(TFRAME/4) – (2 TCY + 40 ns) (TFWR/2 – (1 TCY + 40 ns)) maximum = 1.5(TFRAME/4) – (1 TCY + 40 ns) DS39957B-page 296 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 20.10 Operation During Sleep The LCD module can operate during Sleep. Setting the SLPEN bit (LCDCON<6>) allows the LCD module to go to Sleep. Clearing this bit allows the module to continue operating during Sleep. If a SLEEP instruction is executed and SLPEN = 1, the LCD module will cease all functions and go into a very low-current consumption mode. The module will stop operation immediately and drive the minimum LCD voltage on both segment and common lines. Figure 20-19 shows this operation. The LCD module current consumption will not decrease in this mode, but the overall consumption of the device will be lower due to shut down of the core and other peripheral functions. To ensure that no DC component is introduced on the panel, the SLEEP instruction should be executed immediately after an LCD frame boundary. The LCD FIGURE 20-19: interrupt can be used to determine the frame boundary. For the formulas to calculate the delay, see Section 20.9 “LCD Interrupts”. If a SLEEP instruction is executed and SLPEN = 0, the module will continue to display the current contents of the LCDDATA registers. The LCD data cannot be changed. To allow the module to continue operation while in Sleep, the clock source must be either the internal RC oscillator or Timer1 external oscillator. If the system clock is selected and the module is programmed to not Sleep, the module will ignore the SLPEN bit and stop operation immediately. The minimum LCD voltage then will be driven onto the segments and commons. Note: The internal RC oscillator or external SOSC oscillator must be used to operate the LCD module during Sleep. SLEEP ENTRY/EXIT WHEN SLPEN = 1 OR CS<1:0> = 00 V3 V2 V1 COM0 V0 V3 V2 V1 V0 COM1 V3 V2 V1 V0 COM2 V3 V2 V1 V0 SEG0 2 Frames SLEEP Instruction Execution 2010 Microchip Technology Inc. Preliminary Wake-up DS39957B-page 297 PIC18F87K90 FAMILY 20.11 Configuring the LCD Module 4. To configure the LCD module. 1. 2. 3. Select the frame clock prescale, using bits, LP<3:0> (LCDPS<3:0>). Configure the appropriate pins to function as segment drivers using the LCDSEx registers. If using the internal reference resistors for biasing, enable the internal reference ladder and: • Define the Mode A and Mode B interval by using the LRLAT<2:0> bits (LCDRL<2:0>) • Define the low, medium or high ladder for Mode A and Mode B by using the LRLAP<1:0> bits (LCDRL<7:6>) and the LRLBP<1:0> bits (LCDRL<5:4>), respectively • Set the VLCDxPE bits and enable the LCDIRE bit (LCDREF<7>) DS39957B-page 298 5. 6. 7. Preliminary Configure the following LCD module functions using the LCDCON register: • Multiplex and Bias mode – LMUX<1:0> bits • Timing Source – CS<1:0> bits • Sleep mode – SLPEN bit Write initial values to the pixel data registers, LCDDATA0 through LCDDATA23. Clear the LCD Interrupt Flag, LCDIF (PIR3<6>), and if desired, enable the interrupt by setting bit, LCDIE (PIE3<6>). Enable the LCD module by setting bit, LCDEN (LCDCON<7>). 2010 Microchip Technology Inc. PIC18F87K90 FAMILY TABLE 20-7: Name REGISTERS ASSOCIATED WITH LCD OPERATION Bit 7 INTCON Bit 6 GIE/GIEH PEIE/GIEL Bit 5 Bit 4 TMR0IE Bit 1 Bit 0 Reset Values on Page: Bit 3 Bit 2 INT0IE RBIE TMR0IF INT0IF RBIF 73 TX2IF CTMUIF CCP2IF CCP1IF RTCCIF 75 PIR3 TMR5GIF LCDIF RC2IF PIE3 TMR5GIE LCDIE RC2IE TX2IE CTMUIE CCP2IE CCP1IE RTCCIE 75 IPR3 TMR5GIP LCDIP RC2IP TX2IP CTMUIP CCP2IP CCP1IP RTCCIP 75 IPEN SBOREN CM RI TO PD POR BOR 74 (1) LCDDATA23 S47C3 S46C3 S45C3 S44C3 S43C3 S42C3 S41C3 S40C3 77 LCDDATA22(1) S39C3 S38C3 S37C3 S36C3 S35C3 S34C3 S33C3 S32C3 77 LCDDATA21 S31C3 S30C3 S29C3 S28C3 S27C3 S26C3 S25C3 S24C3 77 LCDDATA20 S23C3 S22C3 S21C3 S20C3 S19C3 S18C3 S17C3 S16C3 77 LCDDATA19 S15C3 S14C3 S13C3 S12C3 S11C3 S10C3 S09C3 S08C3 77 LCDDATA18 S07C3 S06C3 S05C3 S04C3 S03C3 S02C3 S01C3 S00C3 77 (1) LCDDATA17 S47C2 S46C2 S45C2 S44C2 S43C2 S42C2 S41C2 S40C2 77 LCDDATA16(1) S39C2 S38C2 S37C2 S36C2 S35C2 S34C2 S33C2 S32C2 77 LCDDATA15 S31C2 S30C2 S29C2 S28C2 S27C2 S26C2 S25C2 S24C2 77 LCDDATA14 S23C2 S22C2 S21C2 S20C2 S19C2 S18C2 S17C2 S16C2 77 LCDDATA13 S15C2 S14C2 S13C2 S12C2 S11C2 S10C2 S09C2 S08C2 77 LCDDATA12 S07C2 S06C2 S05C2 S04C2 S03C2 S02C2 S01C2 S00C2 77 (1) LCDDATA11 S47C1 S46C1 S45C1 S44C1 S43C1 S42C1 S41C1 S40C1 77 LCDDATA10(1) S39C1 S38C1 S37C1 S36C1 S35C1 S34C1 S33C1 S32C1 77 LCDDATA9 S31C1 S30C1 S29C1 S28C1 S27C1 S26C1 S25C1 S24C1 77 LCDDATA8 S23C1 S22C1 S21C1 S20C1 S19C1 S18C1 S17C1 S16C1 77 LCDDATA7 S15C1 S14C1 S13C1 S12C1 S11C1 S10C1 S09C1 S08C1 77 LCDDATA6 S07C1 S06C1 S05C1 S04C1 S03C1 S02C1 S01C1 S00C1 77 (1) LCDDATA5 S47C0 S46C0 S45C0 S44C0 S43C0 S42C0 S41C0 S40C0 77 LCDDATA4(1) S39C0 S38C0 S37C0 S36C0 S35C0 S34C0 S33C0 S32C0 77 LCDDATA3 S31C0 S30C0 S29C0 S28C0 S27C0 S26C0 S25C0 S24C0 77 LCDDATA2 S23C0 S22C0 S21C0 S20C0 S19C0 S18C0 S17C0 S16C0 77 LCDDATA1 S15C0 S14C0 S13C0 S12C0 S11C0 S10C0 S09C0 S08C0 77 LCDDATA0 S07C0 S06C0 S05C0 S04C0 S03C0 S02C0 S01C0 S00C0 77 (2) LCDSE5 SE47 SE46 SE45 SE44 SE43 SE42 SE41 SE40 81 LCDSE4(2) SE39 SE38 SE37 SE36 SE35 SE34 SE33 SE32 81 LCDSE3 SE31 SE30 SE29 SE28 SE27 SE26 SE25 SE24 81 LCDSE2 SE23 SE22 SE21 SE20 SE19 SE18 SE17 SE16 81 LCDSE1 SE15 SE14 SE13 SE12 SE11 SE10 SE9 SE8 81 LCDSE0 SE7 SE6 SE5 SE4 SE3 SE2 SE1 SE0 81 LCDCON LCDEN SLPEN WERR — CS1 CS0 LMUX1 LMUX0 81 WFT BIASMD LCDA WA LP3 LP2 LP1 LP0 81 RCON LCDPS LCDREF LCDIRE LCDIRS LCDRL LRLAP1 LRLAP0 Legend: Note 1: 2: LCDCST2 LCDCST1 LCDCST0 VLCD3PE VLCD2PE VLCD1PE LRLBP1 LRLBP0 — LRLAT2 LRLAT1 LRLAT0 81 81 — = unimplemented, read as ‘0’. Shaded cells are not used for LCD operations. These registers are implemented, but unused on 64-pin devices and may be used as general purpose data RAM. These registers are unimplemented on 64-pin devices. 2010 Microchip Technology Inc. Preliminary DS39957B-page 299 PIC18F87K90 FAMILY NOTES: DS39957B-page 300 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 21.0 21.1 MASTER SYNCHRONOUS SERIAL PORT (MSSP) MODULE 21.3 The SPI mode allows 8 bits of data to be synchronously transmitted and received simultaneously. All four modes of SPI are supported. To accomplish communication, typically three pins are used: Master SSP (MSSP) Module Overview The Master Synchronous Serial Port (MSSP) module is a serial interface, useful for communicating with other peripheral or microcontroller devices. These peripheral devices may be serial EEPROMs, shift registers, display drivers, A/D Converters, etc. The MSSP module can operate in one of two modes: • Serial Peripheral Interface (SPI) • Inter-Integrated Circuit (I2C™) - Full Master mode - Slave mode (with general address call) • Serial Data Out (SDOx) – RC5/SDO1/SEG12 or RD4/SEG4/SDO2 • Serial Data In (SDIx) – RC4/SDI1/SDA1/SEG16 or RD5/SEG5/SDI2/SDA2 • Serial Clock (SCKx) – RC3/SCK1/SCL1/SEG17 or RD6/SEG6/SCK2/SCL2 Additionally, a fourth pin may be used when in a Slave mode of operation: • Slave Select (SSx) – RF7/AN5/SS1/SEG25 or RD7/SEG7/SS2 The I2C interface supports the following modes in hardware: • Master mode • Multi-Master mode • Slave mode with 5-bit and 7-bit address masking (with address masking for both 10-bit and 7-bit addressing) Figure 21-1 shows the block diagram of the MSSP module when operating in SPI mode. FIGURE 21-1: 21.2 Read SDIx Throughout this section, generic references to an MSSP module in any of its operating modes may be interpreted as being equally applicable to MSSP1 or MSSP2. Register names and module I/O signals use the generic designator ‘x’ to indicate the use of a numeral to distinguish a particular module when required. Control bit names are not individuated. SSPxSR reg SDOx SSx Control Registers Shift Clock bit 0 SSx Control Enable Edge Select 2 Clock Select SCKx Additional details are provided under the individual sections. In devices with more than one MSSP module, it is very important to pay close attention to SSPxCON register names. SSP1CON1 and SSP1CON2 control different operational aspects of the same module, while SSP1CON1 and SSP2CON1 control the same features for two different modules. 2010 Microchip Technology Inc. Write SSPxBUF reg Each MSSP module has three associated control registers. These include a status register (SSPxSTAT) and two control registers (SSPxCON1 and SSPxCON2). The use of these registers and their individual configuration bits differ significantly depending on whether the MSSP module is operated in SPI or I2C mode. Note: MSSPx BLOCK DIAGRAM (SPI MODE) Internal Data Bus All members of the PIC18F87K90 family have two MSSP modules, designated as MSSP1 and MSSP2. Each module operates independently of the other. Note: SPI Mode SSPM<3:0> SMP:CKE 4 TMR2 Output 2 2 ( Edge Select ) Prescaler TOSC 4, 16, 64 Data to TXx/RXx in SSPxSR TRIS bit Note: Preliminary Only port I/O names are used in this diagram for the sake of brevity. Refer to the text for a full list of multiplexed functions. DS39957B-page 301 PIC18F87K90 FAMILY 21.3.1 REGISTERS In receive operations, SSPxSR and SSPxBUF together create a double-buffered receiver. When SSPxSR receives a complete byte, it is transferred to SSPxBUF and the SSPxIF interrupt is set. Each MSSP module has four registers for SPI mode operation. These are: • MSSPx Control Register 1 (SSPxCON1) • MSSPx Status Register (SSPxSTAT) • Serial Receive/Transmit Buffer Register (SSPxBUF) • MSSPx Shift Register (SSPxSR) – Not directly accessible During transmission, the SSPxBUF is not double-buffered. A write to SSPxBUF will write to both SSPxBUF and SSPxSR. Note: SSPxCON1 and SSPxSTAT are the control and status registers in SPI mode operation. The SSPxCON1 register is readable and writable. The lower 6 bits of the SSPxSTAT are read-only. The upper two bits of the SSPxSTAT are read/write. The SSPxBUF register cannot be used with read-modify-write instructions, such as BCF, COMF, etc. To avoid lost data in Master mode, a read of the SSPxBUF must be performed to clear the Buffer Full (BF) detect bit (SSPxSTAT<0>) between each transmission. SSPxSR is the shift register used for shifting data in or out. SSPxBUF is the buffer register to which data bytes are written to or read from. REGISTER 21-1: R/W-0 SMP SSPxSTAT: MSSPx STATUS REGISTER (SPI MODE) R/W-0 R-0 R-0 R-0 R-0 R-0 R-0 (1) D/A P S R/W UA BF CKE bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 SMP: Sample bit SPI Master mode: 1 = Input data sampled at the end of data output time 0 = Input data sampled at the middle of data output time SPI Slave mode: SMP must be cleared when SPI is used in Slave mode. bit 6 CKE: SPI Clock Select bit(1) 1 = Transmit occurs on transition from active to Idle clock state 0 = Transmit occurs on transition from Idle to active clock state bit 5 D/A: Data/Address bit Used in I2C™ mode only. bit 4 P: Stop bit Used in I2C mode only. This bit is cleared when the MSSPx module is disabled; SSPEN is cleared. bit 3 S: Start bit Used in I2C mode only. bit 2 R/W: Read/Write Information bit Used in I2C mode only. bit 1 UA: Update Address bit Used in I2C mode only. bit 0 BF: Buffer Full Status bit (Receive mode only) 1 = Receive complete, SSPxBUF is full 0 = Receive not complete, SSPxBUF is empty Note 1: Polarity of the clock state is set by the CKP bit (SSPxCON1<4>). DS39957B-page 302 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY REGISTER 21-2: SSPxCON1: MSSPx CONTROL REGISTER 1 (SPI MODE) R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 WCOL SSPOV(1) SSPEN(2) CKP SSPM3(3) SSPM2(3) SSPM1(3) SSPM0(3) bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 WCOL: Write Collision Detect bit 1 = The SSPxBUF register is written while it is still transmitting the previous word (must be cleared in software) 0 = No collision bit 6 SSPOV: Receive Overflow Indicator bit(1) SPI Slave mode: 1 = A new byte is received while the SSPxBUF register is still holding the previous data. In case of overflow, the data in SSPxSR is lost. Overflow can only occur in Slave mode. The user must read the SSPxBUF, even if only transmitting data, to avoid setting overflow (must be cleared in software). 0 = No overflow bit 5 SSPEN: Master Synchronous Serial Port Enable bit(2) 1 = Enables serial port and configures SCKx, SDOx, SDIx and SSx as serial port pins 0 = Disables serial port and configures these pins as I/O port pins bit 4 CKP: Clock Polarity Select bit 1 = Idle state for clock is a high level 0 = Idle state for clock is a low level bit 3-0 SSPM<3:0>: Master Synchronous Serial Port Mode Select bits(3) 1010 = SPI Master mode: Clock = FOSC/8 0101 = SPI Slave mode: Clock = SCKx pin; SSx pin control disabled; SSx can be used as I/O pin 0100 = SPI Slave mode: Clock = SCKx pin; SSx pin control enabled 0011 = SPI Master mode: Clock = TMR2 Output/2 0010 = SPI Master mode: Clock = FOSC/64 0001 = SPI Master mode: Clock = FOSC/16 0000 = SPI Master mode: Clock = FOSC/4 Note 1: 2: 3: In Master mode, the overflow bit is not set since each new reception (and transmission) is initiated by writing to the SSPxBUF register. When enabled, these pins must be properly configured as inputs or outputs. Bit combinations not specifically listed here are either reserved or implemented in I2C™ mode only. 2010 Microchip Technology Inc. Preliminary DS39957B-page 303 PIC18F87K90 FAMILY 21.3.2 OPERATION When initializing the SPI, several options need to be specified. This is done by programming the appropriate control bits (SSPxCON1<5:0> and SSPxSTAT<7:6>). These control bits allow the following to be specified: • • • • Master mode (SCKx is the clock output) Slave mode (SCKx is the clock input) Clock Polarity (Idle state of SCKx) Data Input Sample Phase (middle or end of data output time) • Clock Edge (output data on rising/falling edge of SCKx) • Clock Rate (Master mode only) • Slave Select mode (Slave mode only) Each MSSP module consists of a transmit/receive shift register (SSPxSR) and a buffer register (SSPxBUF). The SSPxSR shifts the data in and out of the device, MSb first. The SSPxBUF holds the data that was written to the SSPxSR until the received data is ready. Once the 8 bits of data have been received, that byte is moved to the SSPxBUF register. Then, the Buffer Full detect bit, BF (SSPxSTAT<0>), and the interrupt flag bit, SSPxIF, are set. This double-buffering of the received data (SSPxBUF) allows the next byte to start reception before reading the data that was just received. Any write to the SSPxBUF register during transmission/reception of data will be ignored and the Write Collision Detect bit, WCOL (SSPxCON1<7>), will be set. User software must clear the WCOL bit so that it can be determined if the following write(s) to the SSPxBUF register completed successfully. When the application software is expecting to receive valid data, the SSPxBUF should be read before the next byte of data to transfer is written to the SSPxBUF. The Buffer Full bit, BF (SSPxSTAT<0>), indicates when SSPxBUF has been loaded with the received data (transmission is complete). When the SSPxBUF is read, the BF bit is cleared. This data may be irrelevant if the SPI is only a transmitter. Generally, the MSSP interrupt is used to determine when the transmission/reception has completed. If the interrupt method is not going to be used, then software polling can be done to ensure that a write collision does not occur. Example 21-1 shows the loading of the SSPxBUF (SSPxSR) for data transmission. The SSPxSR is not directly readable or writable and can only be accessed by addressing the SSPxBUF register. Additionally, the SSPxSTAT register indicates the various status conditions. 21.3.3 The drivers for the SDOx output and SCKx clock pins can be optionally configured as open-drain outputs. This feature allows the voltage level on the pin to be pulled to a higher level through an external pull-up resistor, and allows the output to communicate with external circuits without the need for additional level shifters. For more information, see Section 11.1.3 “Open-Drain Outputs”. The open-drain output option is controlled by the SSP2OD (ODCON1<0>) and SSP1OD bits (ODCON1<7>). Setting an SSPxOD bit configures the SDOx and SCKx pins for the corresponding module for open-drain operation. Note: EXAMPLE 21-1: LOOP OPEN-DRAIN OUTPUT OPTION To avoid lost data in Master mode, a read of the SSPxBUF must be performed to clear the Buffer Full (BF) detect bit (SSPxSTAT<0>) between each transmission. LOADING THE SSP1BUF (SSP1SR) REGISTER BTFSS BRA MOVF SSP1STAT, BF LOOP SSP1BUF, W MOVWF RXDATA ;Save in user RAM, if data is meaningful MOVF MOVWF TXDATA, W SSP1BUF ;W reg = contents of TXDATA ;New data to xmit DS39957B-page 304 ;Has data been received (transmit complete)? ;No ;WREG reg = contents of SSP1BUF Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 21.3.4 ENABLING SPI I/O To enable the serial port, MSSP Enable bit, SSPEN (SSPxCON1<5>), must be set. To reset or reconfigure SPI mode, clear the SSPEN bit, reinitialize the SSPxCON registers and then set the SSPEN bit. This configures the SDIx, SDOx, SCKx and SSx pins as serial port pins. For the pins to behave as the serial port function, some must have their data direction bits (in the TRIS register) appropriately programmed as follows: • SDIx is automatically controlled by the SPI module • SDOx must have the TRISC<5> or TRISD<4> bit cleared • SCKx (Master mode) must have the TRISC<3> or TRISD<6>bit cleared • SCKx (Slave mode) must have the TRISC<3> or TRISD<6> bit set • SSx must have the TRISF<7> or TRISD<7> bit set FIGURE 21-2: Any serial port function that is not desired may be overridden by programming the corresponding Data Direction (TRIS) register to the opposite value. 21.3.5 TYPICAL CONNECTION Figure 21-2 shows a typical connection between two microcontrollers. The master controller (Processor 1) initiates the data transfer by sending the SCKx signal. Data is shifted out of both shift registers on their programmed clock edge and latched on the opposite edge of the clock. Both processors should be programmed to the same Clock Polarity (CKP), then both controllers would send and receive data at the same time. Whether the data is meaningful (or dummy data) depends on the application software. This leads to three scenarios for data transmission: • Master sends data–Slave sends dummy data • Master sends data–Slave sends data • Master sends dummy data–Slave sends data SPI MASTER/SLAVE CONNECTION SPI Master SSPM<3:0> = 00xxb SPI Slave SSPM<3:0> = 010xb SDOx SDIx Serial Input Buffer (SSPxBUF) SDIx Shift Register (SSPxSR) MSb Serial Input Buffer (SSPxBUF) SDOx LSb MSb SCKx Serial Clock PROCESSOR 1 2010 Microchip Technology Inc. Shift Register (SSPxSR) LSb SCKx PROCESSOR 2 Preliminary DS39957B-page 305 PIC18F87K90 FAMILY 21.3.6 MASTER MODE The master can initiate the data transfer at any time because it controls the SCKx. The master determines when the slave (Processor 1, Figure 21-2) is to broadcast data by the software protocol. In Master mode, the data is transmitted/received as soon as the SSPxBUF register is written to. If the SPI is only going to receive, the SDOx output could be disabled (programmed as an input). The SSPxSR register will continue to shift in the signal present on the SDIx pin at the programmed clock rate. As each byte is received, it will be loaded into the SSPxBUF register as if a normal received byte (interrupts and status bits appropriately set). This could be useful in receiver applications as a “Line Activity Monitor” mode. The clock polarity is selected by appropriately programming the CKP bit (SSPxCON1<4>). This, then, would give waveforms for SPI communication as FIGURE 21-3: shown in Figure 21-3, Figure 21-5 and Figure 21-6, where the MSB is transmitted first. In Master mode, the SPI clock rate (bit rate) is user-programmable to be one of the following: • • • • FOSC/4 (or TCY) FOSC/16 (or 4 • TCY) FOSC/64 (or 16 • TCY) Timer2 output/2 This allows a maximum data rate (at 40 MHz) of 10.00 Mbps. Figure 21-3 shows the waveforms for Master mode. When the CKE bit is set, the SDOx data is valid before there is a clock edge on SCKx. The change of the input sample is shown based on the state of the SMP bit. The time when the SSPxBUF is loaded with the received data is shown. SPI MODE WAVEFORM (MASTER MODE) Write to SSPxBUF SCKx (CKP = 0 CKE = 0) SCKx (CKP = 1 CKE = 0) 4 Clock Modes SCKx (CKP = 0 CKE = 1) SCKx (CKP = 1 CKE = 1) SDOx (CKE = 0) bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 SDOx (CKE = 1) bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 SDIx (SMP = 0) bit 0 bit 7 Input Sample (SMP = 0) SDIx (SMP = 1) bit 0 bit 7 Input Sample (SMP = 1) SSPxIF Next Q4 Cycle after Q2 SSPxSR to SSPxBUF DS39957B-page 306 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 21.3.7 SLAVE MODE In Slave mode, the data is transmitted and received as the external clock pulses appear on SCKx. When the last bit is latched, the SSPxIF interrupt flag bit is set. While in Slave mode, the external clock is supplied by the external clock source on the SCKx pin. This external clock must meet the minimum high and low times as specified in the electrical specifications. While in Sleep mode, the slave can transmit/receive data. When a byte is received, the device can be configured to wake-up from Sleep. 21.3.8 SLAVE SELECT SYNCHRONIZATION The SSx pin allows a Synchronous Slave mode. The SPI must be in Slave mode with the SSx pin control enabled (SSPxCON1<3:0> = 04h). When the SSx pin is low, transmission and reception are enabled and the SDOx pin is driven. When the SSx pin goes high, the SDOx pin is no longer driven, even if in the middle of a FIGURE 21-4: transmitted byte and becomes a floating output. External pull-up/pull-down resistors may be desirable depending on the application. Note 1: When the SPI is in Slave mode control enabled with SSx pin (SSPxCON1<3:0> = 0100), the SPI module will reset if the SSx pin is set to VDD. 2: If the SPI is used in Slave mode with CKE set, then the SSx pin control must be enabled. When the SPI module resets, the bit counter is forced to ‘0’. This can be done by either forcing the SSx pin to a high level or clearing the SSPEN bit. To emulate two-wire communication, the SDOx pin can be connected to the SDIx pin. When the SPI needs to operate as a receiver, the SDOx pin can be configured as an input. This disables transmissions from the SDOx. The SDIx can always be left as an input (SDIx function) since it cannot create a bus conflict. SLAVE SYNCHRONIZATION WAVEFORM SSx SCKx (CKP = 0 CKE = 0) SCKx (CKP = 1 CKE = 0) Write to SSPxBUF SDOx SDIx (SMP = 0) bit 7 bit 6 bit 7 bit 0 bit 0 bit 7 bit 7 Input Sample (SMP = 0) SSPxIF Interrupt Flag Next Q4 Cycle after Q2 SSPxSR to SSPxBUF 2010 Microchip Technology Inc. Preliminary DS39957B-page 307 PIC18F87K90 FAMILY FIGURE 21-5: SPI MODE WAVEFORM (SLAVE MODE WITH CKE = 0) SSx Optional SCKx (CKP = 0 CKE = 0) SCKx (CKP = 1 CKE = 0) Write to SSPxBUF SDOx SDIx (SMP = 0) bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 bit 0 bit 7 Input Sample (SMP = 0) SSPxIF Interrupt Flag Next Q4 Cycle after Q2 SSPxSR to SSPxBUF FIGURE 21-6: SPI MODE WAVEFORM (SLAVE MODE WITH CKE = 1) SSx Not Optional SCKx (CKP = 0 CKE = 1) SCKx (CKP = 1 CKE = 1) Write to SSPxBUF SDOx SDIx (SMP = 0) bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0 bit 0 bit 7 Input Sample (SMP = 0) SSPxIF Interrupt Flag Next Q4 Cycle after Q2 SSPxSR to SSPxBUF DS39957B-page 308 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 21.3.9 OPERATION IN POWER-MANAGED MODES In SPI Master mode, module clocks may be operating at a different speed than when in full-power mode; in the case of the Sleep mode, all clocks are halted. In Idle modes, a clock is provided to the peripherals. That clock can be from the primary clock source, the secondary clock (SOSC oscillator) or the INTOSC source. See Section 3.3 “Clock Sources and Oscillator Switching” for additional information. 21.3.11 Table 21-1 shows the compatibility between the standard SPI modes and the states of the CKP and CKE control bits. TABLE 21-1: If the Sleep mode is selected, all module clocks are halted and the transmission/reception will remain in that state until the device wakes. After the device returns to Run mode, the module will resume transmitting and receiving data. In SPI Slave mode, the SPI Transmit/Receive Shift register operates asynchronously to the device. This allows the device to be placed in any power-managed mode and data to be shifted into the SPI Transmit/Receive Shift register. When all 8 bits have been received, the MSSP interrupt flag bit will be set, and if enabled, will wake the device. 21.3.10 SPI BUS MODES Control Bits State Standard SPI Mode Terminology CKP CKE 0, 0 0 1 0, 1 0 0 1, 0 1 1 1, 1 1 0 In most cases, the speed that the master clocks SPI data is not important; however, this should be evaluated for each system. If MSSP interrupts are enabled, they can wake the controller from Sleep mode, or one of the Idle modes, when the master completes sending data. If an exit from Sleep or Idle mode is not desired, MSSP interrupts should be disabled. BUS MODE COMPATIBILITY There is also an SMP bit which controls when the data is sampled. 21.3.12 SPI CLOCK SPEED AND MODULE INTERACTIONS Because MSSP1 and MSSP2 are independent modules, they can operate simultaneously at different data rates. Setting the SSPM<3:0> bits of the SSPxCON1 register determines the rate for the corresponding module. An exception is when both modules use Timer2 as a time base in Master mode. In this instance, any changes to the Timer2 module’s operation will affect both MSSP modules equally. If different bit rates are required for each module, the user should select one of the other three time base options for one of the modules. EFFECTS OF A RESET A Reset disables the MSSP module and terminates the current transfer. 2010 Microchip Technology Inc. Preliminary DS39957B-page 309 PIC18F87K90 FAMILY TABLE 21-2: Name REGISTERS ASSOCIATED WITH SPI OPERATION Bit 6 Bit 5 Bit 4 GIE/GIEH PEIE/GIEL TMR0IE INT0IE RBIE TMR0IF INT0IF RBIF 73 PIR1 — ADIF RC1IF TX1IF SSP1IF TMR1GIF TMR2IF TMR1IF 75 PIE1 — ADIE RC1IE TX1IE SSP1IE TMR1GIE TMR2IE TMR1IE 75 IPR1 — ADIP RC1IP TX1IP SSP1IP TMR1GIP TMR2IP TMR1IP 75 PIR2 OSCFIF — SSP2IF BCL2IF BCL1IF HLVDIF TMR3IF TMR3GIF 75 INTCON Bit 3 Bit 2 Bit 1 Bit 0 Reset Values on Page: Bit 7 PIE2 OSCFIE — SSP2IE BCL2IE BCL1IE HLVDIE TMR3IE TMR3GIE 75 IPR2 OSCFIP — SSP2IP BCL2IP BCL1IP HLVDIP TMR3IP TMR3GIP 75 TRISC TRISC7 TRISC6 TRISC5 TRISC4 TRISC3 TRISC2 TRISC1 TRISC0 76 TRISD TRISD7 TRISD6 TRISD5 TRISD4 TRISD3 TRISD2 TRISD1 TRISD0 76 TRISF7 TRISF6 TRISF5 TRISF4 TRISF3 TRISF2 TRISF1 — TRISF SSP1BUF MSSP1 Receive Buffer/Transmit Register 76 80 SSP1CON1 WCOL SSPOV SSPEN CKP SSPM3 SSPM2 SSPM1 SSPM0 74 SSP1CON2 GCEN ACKSTAT ACKDT ACKEN RCEN PEN RSEN SEN 74 SSP1STAT SMP CKE D/A P S R/W UA BF 74 SSP2CON1 WCOL SSPOV SSPEN CKP SSPM3 SSPM2 SSPM1 SSPM0 80 SSP2CON2 GCEN ACKSTAT ACKDT ACKEN RCEN PEN RSEN SEN 81 SMP CKE D/A P S R/W UA BF SSP2STAT SSP2BUF ODCON3 Legend: MSSP2 Receive Buffer/Transmit Register U2OD U1OD — 80 80 — — — — CTMUDS 79 Shaded cells are not used by the MSSP module in SPI mode. DS39957B-page 310 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 21.4 I2C™ Mode 21.4.1 The MSSP module in I 2C mode fully implements all master and slave functions (including general call support), and provides interrupts on Start and Stop bits in hardware to determine a free bus (multi-master function). The MSSP module implements the standard mode specifications, as well as 7-bit and 10-bit addressing. Two pins are used for data transfer: • Serial Clock (SCLx) – RC3/SCK1/SCL1/SEG17 or RD6/SEG6/SCK2/SCL2 • Serial Data (SDAx) – RC4/SDI1/SDA1/SEG16 or RD5/SEG5/SDI2/SDA2 The user must configure these pins as inputs by setting the associated TRIS bits. FIGURE 21-7: MSSPx BLOCK DIAGRAM (I2C™ MODE) Write Shift Clock MSb LSb Match Detect Addr Match Address Mask SSPxADD reg Start and Stop bit Detect Note: MSSPx Control Register 1 (SSPxCON1) MSSPx Control Register 2 (SSPxCON2) MSSPx Status Register (SSPxSTAT) Serial Receive/Transmit Buffer Register (SSPxBUF) • MSSPx Shift Register (SSPxSR) – Not directly accessible • MSSPx Address Register (SSPxADD) • I2C Slave Address Mask Register (SSPxMSK) SSPxCON1, SSPxCON2 and SSPxSTAT are the control and status registers in I2C mode operation. The SSPxCON1 and SSPxCON2 registers are readable and writable. The lower 6 bits of the SSPxSTAT are read-only. The upper two bits of the SSPxSTAT are read/write. SSPxMSK holds the slave address mask value when the module is configured for 7-Bit Address Masking mode. While it is a separate register, it shares the same SFR address as SSPxADD. It is only accessible when the SSPM<3:0> bits are specifically set to permit access. Additional details are provided in Section 21.4.3.4 “7-Bit Address Masking Mode”. SSPxSR reg SDAx • • • • SSPxADD contains the slave device address when the MSSP is configured in I2C Slave mode. When the MSSP is configured in Master mode, the lower seven bits of SSPxADD act as the Baud Rate Generator reload value. SSPxBUF reg SCLx The MSSP module has seven registers for I2C operation. These are: SSPxSR is the shift register used for shifting data in or out. SSPxBUF is the buffer register to which data bytes are written to or read from. Internal Data Bus Read REGISTERS Set, Reset S, P bits (SSPxSTAT reg) In receive operations, SSPxSR and SSPxBUF together, create a double-buffered receiver. When SSPxSR receives a complete byte, it is transferred to SSPxBUF and the SSPxIF interrupt is set. During transmission, the SSPxBUF is not double-buffered. A write to SSPxBUF will write to both SSPxBUF and SSPxSR. Only port I/O names are used in this diagram for the sake of brevity. Refer to the text for a full list of multiplexed functions. 2010 Microchip Technology Inc. Preliminary DS39957B-page 311 PIC18F87K90 FAMILY REGISTER 21-3: SSPxSTAT: MSSPx STATUS REGISTER (I2C™ MODE) R/W-0 R/W-0 R-0 R-0 R-0 R-0 R-0 R-0 SMP CKE D/A P(1) S(1) R/W(2,3) UA BF bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 SMP: Slew Rate Control bit In Master or Slave mode: 1 = Slew rate control is disabled for Standard Speed mode (100 kHz and 1 MHz) 0 = Slew rate control is enabled for High-Speed mode (400 kHz) bit 6 CKE: SMBus Select bit In Master or Slave mode: 1 = Enable SMBus-specific inputs 0 = Disable SMBus-specific inputs bit 5 D/A: Data/Address bit In Master mode: Reserved. In Slave mode: 1 = Indicates that the last byte received or transmitted was data 0 = Indicates that the last byte received or transmitted was an address bit 4 P: Stop bit(1) 1 = Indicates that a Stop bit has been detected last 0 = Stop bit was not detected last bit 3 S: Start bit(1) 1 = Indicates that a Start bit has been detected last 0 = Start bit was not detected last bit 2 R/W: Read/Write Information bit(2,3) In Slave mode: 1 = Read 0 = Write In Master mode: 1 = Transmit is in progress 0 = Transmit is not in progress bit 1 UA: Update Address bit (10-Bit Slave mode only) 1 = Indicates that the user needs to update the address in the SSPxADD register 0 = Address does not need to be updated bit 0 BF: Buffer Full Status bit In Transmit mode: 1 = SSPxBUF is full 0 = SSPxBUF is empty In Receive mode: 1 = SSPxBUF is full (does not include the ACK and Stop bits) 0 = SSPxBUF is empty (does not include the ACK and Stop bits) Note 1: 2: 3: This bit is cleared on Reset and when SSPEN is cleared. This bit holds the R/W bit information following the last address match. This bit is only valid from the address match to the next Start bit, Stop bit or not ACK bit. ORing this bit with SEN, RSEN, PEN, RCEN or ACKEN will indicate if the MSSPx is in Active mode. DS39957B-page 312 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY REGISTER 21-4: R/W-0 SSPxCON1: MSSPx CONTROL REGISTER 1 (I2C™ MODE) R/W-0 WCOL R/W-0 SSPOV SSPEN (1) R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 CKP SSPM3(2) SSPM2(2) SSPM1(2) SSPM0(2) bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 WCOL: Write Collision Detect bit In Master Transmit mode: 1 = A write to the SSPxBUF register was attempted while the I2C conditions were not valid for a transmission to be started (must be cleared in software) 0 = No collision In Slave Transmit mode: 1 = The SSPxBUF register is written while it is still transmitting the previous word (must be cleared in software) 0 = No collision In Receive mode (Master or Slave modes): This is a “don’t care” bit. bit 6 SSPOV: Receive Overflow Indicator bit In Receive mode: 1 = A byte is received while the SSPxBUF register is still holding the previous byte (must be cleared in software) 0 = No overflow In Transmit mode: This is a “don’t care” bit in Transmit mode. bit 5 SSPEN: Master Synchronous Serial Port Enable bit(1) 1 = Enables the serial port and configures the SDAx and SCLx pins as the serial port pins 0 = Disables the serial port and configures these pins as I/O port pins bit 4 CKP: SCKx Release Control bit In Slave mode: 1 = Releases clock 0 = Holds clock low (clock stretch), used to ensure data setup time In Master mode: Unused in this mode. bit 3-0 SSPM<3:0>: Master Synchronous Serial Port Mode Select bits(2) 1111 = I2C Slave mode: 10-bit address with Start and Stop bit interrupts enabled 1110 = I2C Slave mode: 7-bit address with Start and Stop bit interrupts enabled 1011 = I2C Firmware Controlled Master mode (slave Idle) 1001 = Load the SSPMSK register at the SSPxADD SFR address(3,4) 1000 = I2C Master mode: Clock = FOSC/(4 * (SSPxADD + 1)) 0111 = I2C Slave mode: 10-bit address 0110 = I2C Slave mode: 7-bit address Note 1: 2: 3: 4: When enabled, the SDAx and SCLx pins must be configured as inputs. Bit combinations not specifically listed here are either reserved or implemented in SPI mode only. When SSPM<3:0> = 1001, any reads or writes to the SSPxADD SFR address actually access the SSPxMSK register. This mode is only available when 7-Bit Address Masking mode is selected (MSSPMSK Configuration bit is ‘1’). 2010 Microchip Technology Inc. Preliminary DS39957B-page 313 PIC18F87K90 FAMILY REGISTER 21-5: SSPxCON2: MSSPx CONTROL REGISTER 2 (I2C™ MASTER MODE) R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 GCEN ACKSTAT ACKDT(1) ACKEN(2) RCEN(2) PEN(2) RSEN(2) SEN(2) bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 GCEN: General Call Enable bit Unused in Master mode. bit 6 ACKSTAT: Acknowledge Status bit (Master Transmit mode only) 1 = Acknowledge was not received from slave 0 = Acknowledge was received from slave bit 5 ACKDT: Acknowledge Data bit (Master Receive mode only)(1) 1 = Not Acknowledge 0 = Acknowledge bit 4 ACKEN: Acknowledge Sequence Enable bit(2) 1 = Initiates Acknowledge sequence on SDAx and SCLx pins and transmits ACKDT data bit; automatically cleared by hardware 0 = Acknowledge sequence is Idle bit 3 RCEN: Receive Enable bit (Master Receive mode only)(2) 1 = Enables Receive mode for I2C 0 = Receive is Idle bit 2 PEN: Stop Condition Enable bit(2) 1 = Initiates Stop condition on SDAx and SCLx pins; automatically cleared by hardware 0 = Stop condition is Idle bit 1 RSEN: Repeated Start Condition Enable bit(2) 1 = Initiates Repeated Start condition on SDAx and SCLx pins; automatically cleared by hardware 0 = Repeated Start condition is Idle bit 0 SEN: Start Condition Enable bit(2) 1 = Initiates Start condition on SDAx and SCLx pins; automatically cleared by hardware 0 = Start condition is Idle Note 1: 2: Value that will be transmitted when the user initiates an Acknowledge sequence at the end of a receive. If the I2C module is active, these bits may not be set (no spooling) and the SSPxBUF may not be written (or writes to the SSPxBUF are disabled). DS39957B-page 314 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY REGISTER 21-6: SSPxCON2: MSSPx CONTROL REGISTER 2 (I2C™ SLAVE MODE) R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 GCEN ACKSTAT ADMSK5 ADMSK4 ADMSK3 ADMSK2 ADMSK1 SEN(1) bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 GCEN: General Call Enable bit 1 = Enables interrupt when a general call address (0000h) is received in the SSPxSR 0 = General call address is disabled bit 6 ACKSTAT: Acknowledge Status bit Unused in Slave mode. bit 5-2 ADMSK<5:2>: Slave Address Mask Select bits (5-Bit Address Masking mode) 1 = Masking of corresponding bits of SSPxADD is enabled 0 = Masking of corresponding bits of SSPxADD is disabled bit 1 ADMSK1: Slave Address Least Significant bit(s) Mask Select bit In 7-Bit Addressing mode: 1 = Masking of SSPxADD<1> only is enabled 0 = Masking of SSPxADD<1> only is disabled In 10-Bit Addressing mode: 1 = Masking of SSPxADD<1:0> is enabled 0 = Masking of SSPxADD<1:0> is disabled bit 0 SEN: Stretch Enable bit(1) 1 = Clock stretching is enabled for both slave transmit and slave receive (stretch enabled) 0 = Clock stretching is disabled Note 1: If the I2C module is active, this bit may not be set (no spooling) and the SSPxBUF may not be written (or writes to the SSPxBUF are disabled). REGISTER 21-7: SSPxMSK: I2C™ SLAVE ADDRESS MASK REGISTER (7-BIT MASKING MODE)(1) R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 MSK7 MSK6 MSK5 MSK4 MSK3 MSK2 MSK1 MSK0(2) bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7-0 x = Bit is unknown MSK<7:0>: Slave Address Mask Select bit 1 = Masking of the corresponding bit of SSPxADD is enabled 0 = Masking of the corresponding bit of SSPxADD is disabled Note 1: 2: This register shares the same SFR address as SSPxADD and is only addressable in select MSSPx operating modes. See Section 21.4.3.4 “7-Bit Address Masking Mode” for more details. MSK0 is not used as a mask bit in 7-bit addressing. 2010 Microchip Technology Inc. Preliminary DS39957B-page 315 PIC18F87K90 FAMILY 21.4.2 OPERATION 21.4.3.1 The MSSP module functions are enabled by setting the MSSP Enable bit, SSPEN (SSPxCON1<5>). The SSPxCON1 register allows control of the I2C operation. Four mode selection bits (SSPxCON1<3:0>) allow one of the following I2C modes to be selected: I2C Master mode, clock I 2C Slave mode (7-bit address) I 2C Slave mode (10-bit address) I 2C Slave mode (7-bit address) with Start and Stop bit interrupts enabled • I 2C Slave mode (10-bit address) with Start and Stop bit interrupts enabled • I 2C Firmware Controlled Master mode, slave is Idle • • • • 21.4.3 Once the MSSP module has been enabled, it waits for a Start condition to occur. Following the Start condition, the 8 bits are shifted into the SSPxSR register. All incoming bits are sampled with the rising edge of the clock (SCLx) line. The value of register, SSPxSR<7:1>, is compared to the value of the SSPxADD register. The address is compared on the falling edge of the eighth clock (SCLx) pulse. If the addresses match and the BF and SSPOV bits are clear, the following events occur: 1. 2. 3. 4. Selection of any I 2C mode with the SSPEN bit set forces the SCLx and SDAx pins to be open-drain, provided these pins are programmed as inputs by setting the appropriate TRISC or TRISD bits. To ensure proper operation of the module, pull-up resistors must be provided externally to the SCLx and SDAx pins. SLAVE MODE In Slave mode, the SCLx and SDAx pins must be configured as inputs (TRISC<4:3> set). The MSSP module will override the input state with the output data when required (slave-transmitter). The I 2C Slave mode hardware will always generate an interrupt on an address match. Address masking will allow the hardware to generate an interrupt for more than one address (up to 31 in 7-bit addressing and up to 63 in 10-bit addressing). Through the mode select bits, the user can also choose to interrupt on Start and Stop bits. When an address is matched, or the data transfer after an address match is received, the hardware automatically will generate the Acknowledge (ACK) pulse and load the SSPxBUF register with the received value currently in the SSPxSR register. Any combination of the following conditions will cause the MSSP module not to give this ACK pulse: • The Buffer Full bit, BF (SSPxSTAT<0>), was set before the transfer was received. • The overflow bit, SSPOV (SSPxCON1<6>), was set before the transfer was received. Addressing The SSPxSR register value is loaded into the SSPxBUF register. The Buffer Full bit, BF, is set. An ACK pulse is generated. The MSSP Interrupt Flag bit, SSPxIF, is set (and interrupt is generated, if enabled) on the falling edge of the ninth SCLx pulse. In 10-Bit Addressing mode, two address bytes need to be received by the slave. The five Most Significant bits (MSbs) of the first address byte specify if this is a 10-bit address. The R/W bit (SSPxSTAT<2>) must specify a write so the slave device will receive the second address byte. For a 10-bit address, the first byte would equal ‘11110 A9 A8 0’, where ‘A9’ and ‘A8’ are the two MSbs of the address. The sequence of events for 10-bit addressing is as follows, with steps, 7 through 9, for the slave-transmitter: 1. 2. 3. 4. 5. 6. 7. 8. 9. Receive first (high) byte of address (bits, SSPxIF, BF and UA, are set on address match). Update the SSPxADD register with second (low) byte of address (clears bit, UA, and releases the SCLx line). Read the SSPxBUF register (clears bit, BF) and clear flag bit, SSPxIF. Receive second (low) byte of address (bits, SSPxIF, BF and UA, are set). Update the SSPxADD register with the first (high) byte of address. If match releases the SCLx line, this will clear bit, UA. Read the SSPxBUF register (clears bit, BF) and clear flag bit, SSPxIF. Receive Repeated Start condition. Receive first (high) byte of address (bits, SSPxIF and BF, are set). Read the SSPxBUF register (clears bit, BF) and clear flag bit, SSPxIF. In this case, the SSPxSR register value is not loaded into the SSPxBUF, but bit, SSPxIF, is set. The BF bit is cleared by reading the SSPxBUF register, while bit, SSPOV, is cleared through software. The SCLx clock input must have a minimum high and low for proper operation. The high and low times of the I2C specification, as well as the requirement of the MSSP module, are shown in timing parameter 100 and parameter 101. DS39957B-page 316 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 21.4.3.2 Address Masking Modes Masking an address bit causes that bit to become a “don’t care”. When one address bit is masked, two addresses will be Acknowledged and cause an interrupt. It is possible to mask more than one address bit at a time, which greatly expands the number of addresses Acknowledged. The I2C slave behaves the same way whether address masking is used or not. However, when address masking is used, the I2C slave can Acknowledge multiple addresses and cause interrupts. When this occurs, it is necessary to determine which address caused the interrupt by checking the SSPxBUF. The PIC18F87K90 family of devices is capable of using two different Address Masking modes in I2C slave operation: 5-Bit Address Masking and 7-Bit Address Masking. The Masking mode is selected at device configuration using the MSSPMSK Configuration bit. The default device configuration is 7-Bit Address Masking. Both Masking modes, in turn, support address masking of 7-bit and 10-bit addresses. The combination of Masking modes and addresses provide different ranges of Acknowledgable addresses for each combination. While both Masking modes function in roughly the same manner, the way they use address masks are different. 21.4.3.3 Acknowledge up to 31 addresses when using 7-bit addressing, or 63 addresses with 10-bit addressing (see Example 21-2). This Masking mode is selected when the MSSPMSK Configuration bit is programmed (‘0’). The address mask in this mode is stored in the SSPxCON2 register, which stops functioning as a control register in I2C Slave mode (Register 21-6). In 7-Bit Address Masking mode, address mask bits, ADMSK<5:1> (SSPxCON2<5:1>), mask the corresponding address bits in the SSPxADD register. For any ADMSK bits that are set (ADMSK<n> = 1), the corresponding address bit is ignored (SSPxADD<n> = x). For the module to issue an address Acknowledge, it is sufficient to match only on addresses that do not have an active address mask. In 10-Bit Address Masking mode, bits, ADMSK<5:2>, mask the corresponding address bits in the SSPxADD register. In addition, ADMSK1 simultaneously masks the two LSbs of the address (SSPxADD<1:0>). For any ADMSK bits that are active (ADMSK<n> = 1), the corresponding address bit is ignored (SPxADD<n> = x). Also note, that although in 10-Bit Address Masking mode, the upper address bits reuse part of the SSPxADD register bits. The address mask bits do not interact with those bits; they only affect the lower address bits. Note 1: ADMSK1 masks the two Least Significant bits of the address. 5-Bit Address Masking Mode As the name implies, 5-Bit Address Masking mode uses an address mask of up to 5 bits to create a range of addresses to be Acknowledged, using bits, 5 through 1, of the incoming address. This allows the module to EXAMPLE 21-2: 2: The two Most Significant bits of the address are not affected by address masking. ADDRESS MASKING EXAMPLES IN 5-BIT MASKING MODE 7-Bit Addressing: SSPxADD<7:1>= A0h (1010000) (SSPxADD<0> is assumed to be ‘0’) ADMSK<5:1> = 00111 Addresses Acknowledged: A0h, A2h, A4h, A6h, A8h, AAh, ACh, AEh 10-Bit Addressing: SSPxADD<7:0> = A0h (10100000) (The two MSb of the address are ignored in this example, since they are not affected by masking) ADMSK<5:1> = 00111 Addresses Acknowledged: A0h, A1h, A2h, A3h, A4h, A5h, A6h, A7h, A8h, A9h, AAh, ABh, ACh, ADh, AEh, AFh 2010 Microchip Technology Inc. Preliminary DS39957B-page 317 PIC18F87K90 FAMILY 21.4.3.4 7-Bit Address Masking Mode Unlike 5-bit masking, 7-Bit Address Masking mode uses a mask of up to 8 bits (in 10-bit addressing) to define a range of addresses that can be Acknowledged, using the lowest bits of the incoming address. This allows the module to Acknowledge up to 127 different addresses with 7-bit addressing, or 255 with 10-bit addressing (see Example 21-3). This mode is the default configuration of the module and is selected when MSSPMSK is unprogrammed (‘1’). The address mask for 7-Bit Address Masking mode is stored in the SSPxMSK register, instead of the SSPxCON2 register. SSPxMSK is a separate hardware register within the module, but it is not directly addressable. Instead, it shares an address in the SFR space with the SSPxADD register. To access the SSPxMSK register, it is necessary to select MSSP mode, ‘1001’ (SSPxCON1<3:0> = 1001) and then read or write to the location of SSPxADD. To use 7-Bit Address Masking mode, it is necessary to initialize SSPxMSK with a value before selecting the I2C Slave Addressing mode. Thus, the required sequence of events is: 1. 2. 3. Setting or clearing mask bits in SSPxMSK behaves in the opposite manner of the ADMSK bits in 5-Bit Address Masking mode. That is, clearing a bit in SSPxMSK causes the corresponding address bit to be masked; setting the bit requires a match in that position. SSPxMSK resets to all ‘1’s upon any Reset condition and, therefore, has no effect on the standard MSSP operation until written with a mask value. With 7-bit addressing, SSPxMSK<7:1> bits mask the corresponding address bits in the SSPxADD register. For any SSPxMSK bits that are active (SSPxMSK<n> = 0), the corresponding SSPxADD address bit is ignored (SSPxADD<n> = x). For the module to issue an address Acknowledge, it is sufficient to match only on addresses that do not have an active address mask. With 10-bit addressing, SSPxMSK<7:0> bits mask the corresponding address bits in the SSPxADD register. For any SSPxMSK bits that are active (= 0), the corresponding SSPxADD address bit is ignored (SSPxADD<n> = x). Note: Select SSPxMSK Access mode (SSPxCON2<3:0> = 1001). Write the mask value to the appropriate SSPxADD register address (FC8h for MSSP1, F6Eh for MSSP2). Set the appropriate I2C Slave mode (SSPxCON2<3:0> = 0111 for 10-bit addressing, 0110 for 7-bit addressing). EXAMPLE 21-3: The two Most Significant bits of the address are not affected by address masking. ADDRESS MASKING EXAMPLES IN 7-BIT MASKING MODE 7-Bit Addressing: SSPxADD<7:1> = 1010 000 SSPxMSK<7:1> = 1111 001 Addresses Acknowledged = ACh, A8h, A4h, A0h 10-Bit Addressing: SSPxADD<7:0> = 1010 0000 SSPxMSK<7:0> = 1111 0011 Addresses Acknowledged = ACh, A8h, A4h, A0h DS39957B-page 318 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 21.4.3.5 Reception 21.4.3.6 When the R/W bit of the address byte is clear and an address match occurs, the R/W bit of the SSPxSTAT register is cleared. The received address is loaded into the SSPxBUF register and the SDAx line is held low (ACK). When the address byte overflow condition exists, then the no Acknowledge (ACK) pulse is given. An overflow condition is defined as either bit, BF (SSPxSTAT<0>), is set or bit, SSPOV (SSPxCON1<6>), is set. An MSSP interrupt is generated for each data transfer byte. The interrupt flag bit, SSPxIF, must be cleared in software. The SSPxSTAT register is used to determine the status of the byte. If SEN is enabled (SSPxCON2<0> = 1), SCLx will be held low (clock stretch) following each data transfer. The clock must be released by setting bit, CKP (SSPxCON1<4>). See Section 21.4.4 “Clock Stretching” for more details. Transmission When the R/W bit of the incoming address byte is set and an address match occurs, the R/W bit of the SSPxSTAT register is set. The received address is loaded into the SSPxBUF register. The ACK pulse will be sent on the ninth bit and pin, SCLx, is held low regardless of SEN (see Section 21.4.4 “Clock Stretching” for more details). By stretching the clock, the master will be unable to assert another clock pulse until the slave is done preparing the transmit data. The transmit data must be loaded into the SSPxBUF register which also loads the SSPxSR register. Then, pin, SCLx, should be enabled by setting bit, CKP (SSPxCON1<4>). The eight data bits are shifted out on the falling edge of the SCLx input. This ensures that the SDAx signal is valid during the SCLx high time (Figure 21-10). The ACK pulse from the master-receiver is latched on the rising edge of the ninth SCLx input pulse. If the SDAx line is high (not ACK), then the data transfer is complete. In this case, when the ACK is latched by the slave, the slave logic is reset and the slave monitors for another occurrence of the Start bit. If the SDAx line was low (ACK), the next transmit data must be loaded into the SSPxBUF register. Again, pin, SCLx, must be enabled by setting bit, CKP. An MSSP interrupt is generated for each data transfer byte. The SSPxIF bit must be cleared in software and the SSPxSTAT register is used to determine the status of the byte. The SSPxIF bit is set on the falling edge of the ninth clock pulse. 2010 Microchip Technology Inc. Preliminary DS39957B-page 319 DS39957B-page 320 2 A6 Preliminary 3 4 A4 5 A3 Receiving Address A5 6 A2 (CKP does not reset to ‘0’ when SEN = 0) CKP (SSPxCON<4>) SSPOV (SSPxCON1<6>) BF (SSPxSTAT<0>) SSPxIF (PIR1<3> or PIR3<7>) 1 SCLx S A7 7 A1 8 9 ACK R/W = 0 1 D7 3 4 D4 5 D3 Receiving Data D5 Cleared in software SSPxBUF is read 2 D6 6 D2 7 D1 8 D0 9 ACK 1 D7 2 D6 3 4 D4 5 D3 Receiving Data D5 6 D2 7 D1 8 D0 Bus master terminates transfer P SSPOV is set because SSPxBUF is still full. ACK is not sent. 9 ACK FIGURE 21-8: SDAx PIC18F87K90 FAMILY I2C™ SLAVE MODE TIMING WITH SEN = 0 (RECEPTION, 7-BIT ADDRESS) 2010 Microchip Technology Inc. 2010 Microchip Technology Inc. 2 A6 Preliminary Note 3 A5 4 X 5 A3 6 X 1 3 4 D4 Cleared in software SSPxBUF is read 2 D5 5 D3 6 D2 7 D1 8 D0 In this example, an address equal to A7.A6.A5.X.A3.X.X will be Acknowledged and cause an interrupt. 9 D6 x = Don’t care (i.e., address bit can either be a ‘1’ or a ‘0’). 8 D7 Receiving Data 2: 7 X ACK R/W = 0 1: (CKP does not reset to ‘0’ when SEN = 0) CKP (SSPxCON<4>) SSPOV (SSPxCON1<6>) BF (SSPxSTAT<0>) SSPxIF (PIR1<3> or PIR3<7>) 1 SCLx S A7 Receiving Address 9 ACK 1 D7 2 D6 3 D5 4 D4 5 D3 Receiving Data 6 D2 7 D1 8 D0 Bus master terminates transfer P SSPOV is set because SSPxBUF is still full. ACK is not sent. 9 ACK FIGURE 21-9: SDAx PIC18F87K90 FAMILY I2C™ SLAVE MODE TIMING WITH SEN = 0 AND ADMSK<5:1> = 01011 (RECEPTION, 7-BIT ADDRESS) DS39957B-page 321 DS39957B-page 322 2 Data in sampled 1 A6 Preliminary CKP (SSPxCON<4>) BF (SSPxSTAT<0>) SSPxIF (PIR1<3> or PIR3<7>) S A7 3 4 A4 5 A3 6 A2 Receiving Address A5 7 A1 8 R/W = 1 9 ACK 3 D5 4 5 D3 SSPxBUF is written in software 6 D2 Transmitting Data D4 Cleared in software 2 D6 CKP is set in software Clear by reading SCLx held low while CPU responds to SSPxIF 1 D7 7 8 D0 9 From SSPxIF ISR D1 ACK 1 D7 4 D4 5 D3 Cleared in software 3 D5 6 D2 CKP is set in software SSPxBUF is written in software 2 D6 7 8 D0 9 ACK From SSPxIF ISR D1 Transmitting Data P FIGURE 21-10: SCLx SDAx PIC18F87K90 FAMILY I2C™ SLAVE MODE TIMING (TRANSMISSION, 7-BIT ADDRESS) 2010 Microchip Technology Inc. 2010 Microchip Technology Inc. 2 1 3 1 Preliminary 5 0 7 A8 8 UA is set indicating that the SSPxADD needs to be updated SSPxBUF is written with contents of SSPxSR 6 A9 9 2 X 4 5 A3 6 A2 4 5 6 Cleared in software 3 7 8 9 1 2 4 5 6 Cleared in software 3 D3 D2 Receive Data Byte D1 D0 ACK D7 D6 D5 D4 Cleared by hardware when SSPxADD is updated with high byte of address 2 D3 D2 Note that the Most Significant bits of the address are not affected by the bit masking. 1 D6 D5 D4 3: 9 D7 x = Don’t care (i.e., address bit can either be a ‘1’ or a ‘0’). 8 X Receive Data Byte In this example, an address equal to A9.A8.A7.A6.A5.X.A3.A2.X.X will be Acknowledged and cause an interrupt. UA is set indicating that SSPxADD needs to be updated Cleared by hardware when SSPxADD is updated with low byte of address 7 X Cleared in software 3 A5 Dummy read of SSPxBUF to clear BF flag 1 A6 ACK 1: A7 Receive Second Byte of Address 2: (CKP does not reset to ‘0’ when SEN = 0) CKP (SSPxCON<4>) UA (SSPxSTAT<1>) SSPOV (SSPxCON1<6>) BF (SSPxSTAT<0>) Note 4 1 Cleared in software SSPxIF (PIR1<3> or PIR3<7>) 1 SCLx S 1 ACK R/W = 0 Clock is held low until update of SSPxADD has taken place 7 8 D1 D0 9 P Bus master terminates transfer SSPOV is set because SSPxBUF is still full. ACK is not sent. ACK FIGURE 21-11: SDAx Receive First Byte of Address Clock is held low until update of SSPxADD has taken place PIC18F87K90 FAMILY I2C™ SLAVE MODE TIMING WITH SEN = 0 AND ADMSK<5:1> = 01001 (RECEPTION, 10-BIT ADDRESS) DS39957B-page 323 DS39957B-page 324 2 1 3 1 4 1 5 0 Preliminary 7 A8 8 UA is set indicating that the SSPxADD needs to be updated SSPxBUF is written with contents of SSPxSR 6 A9 9 (CKP does not reset to ‘0’ when SEN = 0) CKP (SSPxCON<4>) UA (SSPxSTAT<1>) SSPOV (SSPxCON1<6>) BF (SSPxSTAT<0>) Cleared in software SSPxIF (PIR1<3> or PIR3<7>) 1 SCLx S 1 ACK R/W = 0 A7 2 4 A4 5 A3 6 A2 8 9 A0 ACK UA is set indicating that SSPxADD needs to be updated Cleared by hardware when SSPxADD is updated with low byte of address 7 A1 Cleared in software 3 A5 Dummy read of SSPxBUF to clear BF flag 1 A6 Receive Second Byte of Address 1 D7 4 5 6 Cleared in software 3 D3 D2 7 8 9 1 2 4 5 6 Cleared in software 3 D3 D2 Receive Data Byte D1 D0 ACK D7 D6 D5 D4 Cleared by hardware when SSPxADD is updated with high byte of address 2 D6 D5 D4 Receive Data Byte Clock is held low until update of SSPxADD has taken place 7 8 D1 D0 9 P Bus master terminates transfer SSPOV is set because SSPxBUF is still full. ACK is not sent. ACK FIGURE 21-12: SDAx Receive First Byte of Address Clock is held low until update of SSPxADD has taken place PIC18F87K90 FAMILY I2C™ SLAVE MODE TIMING WITH SEN = 0 (RECEPTION, 10-BIT ADDRESS) 2010 Microchip Technology Inc. 2010 Microchip Technology Inc. 2 3 1 4 1 Preliminary CKP (SSPxCON1<4>) UA (SSPxSTAT<1>) BF (SSPxSTAT<0>) 5 0 6 7 A9 A8 8 UA is set indicating that the SSPxADD needs to be updated SSPxBUF is written with contents of SSPxSR SSPxIF (PIR1<3> or PIR3<7>) 1 S SCLx 1 Receive First Byte of Address 1 9 ACK 1 3 4 5 Cleared in software 2 7 UA is set indicating that SSPxADD needs to be updated 8 A0 Cleared by hardware when SSPxADD is updated with low byte of address 6 A6 A5 A4 A3 A2 A1 Receive Second Byte of Address Dummy read of SSPxBUF to clear BF flag A7 9 ACK 2 3 1 4 1 Cleared in software 1 1 5 0 6 8 9 ACK R/W = 1 1 2 4 5 6 CKP is set in software 9 P Completion of data transmission clears BF flag 8 ACK Bus master terminates transfer CKP is automatically cleared in hardware, holding SCLx low 7 D4 D3 D2 D1 D0 Cleared in software 3 D7 D6 D5 Transmitting Data Byte Clock is held low until CKP is set to ‘1’ Write of SSPxBUF BF flag is clear initiates transmit at the end of the third address sequence 7 A9 A8 Cleared by hardware when SSPxADD is updated with high byte of address. Dummy read of SSPxBUF to clear BF flag Sr 1 Receive First Byte of Address Clock is held low until update of SSPxADD has taken place FIGURE 21-13: SDAx R/W = 0 Clock is held low until update of SSPxADD has taken place PIC18F87K90 FAMILY I2C™ SLAVE MODE TIMING (TRANSMISSION, 10-BIT ADDRESS) DS39957B-page 325 PIC18F87K90 FAMILY 21.4.4 CLOCK STRETCHING 21.4.4.3 Both 7-Bit and 10-Bit Slave modes implement automatic clock stretching during a transmit sequence. The SEN bit (SSPxCON2<0>) allows clock stretching to be enabled during receives. Setting SEN will cause the SCLx pin to be held low at the end of each data receive sequence. 21.4.4.1 Clock Stretching for 7-Bit Slave Receive Mode (SEN = 1) In 7-Bit Slave Receive mode, on the falling edge of the ninth clock at the end of the ACK sequence, if the BF bit is set, the CKP bit in the SSPxCON1 register is automatically cleared, forcing the SCLx output to be held low. The CKP bit being cleared to ‘0’ will assert the SCLx line low. The CKP bit must be set in the user’s ISR before reception is allowed to continue. By holding the SCLx line low, the user has time to service the ISR and read the contents of the SSPxBUF before the master device can initiate another receive sequence. This will prevent buffer overruns from occurring (see Figure 21-15). Note 1: If the user reads the contents of the SSPxBUF before the falling edge of the ninth clock, thus clearing the BF bit, the CKP bit will not be cleared and clock stretching will not occur. 2: The CKP bit can be set in software regardless of the state of the BF bit. The user should be careful to clear the BF bit in the ISR before the next receive sequence in order to prevent an overflow condition. 21.4.4.2 Clock Stretching for 7-Bit Slave Transmit Mode The 7-Bit Slave Transmit mode implements clock stretching by clearing the CKP bit after the falling edge of the ninth clock if the BF bit is clear. This occurs regardless of the state of the SEN bit. The user’s ISR must set the CKP bit before transmission is allowed to continue. By holding the SCLx line low, the user has time to service the ISR and load the contents of the SSPxBUF before the master device can initiate another transmit sequence (see Figure 21-10). Note 1: If the user loads the contents of SSPxBUF, setting the BF bit before the falling edge of the ninth clock, the CKP bit will not be cleared and clock stretching will not occur. 2: The CKP bit can be set in software regardless of the state of the BF bit. 21.4.4.4 Clock Stretching for 10-Bit Slave Transmit Mode In 10-Bit Slave Transmit mode, clock stretching is controlled during the first two address sequences by the state of the UA bit, just as it is in 10-Bit Slave Receive mode. The first two addresses are followed by a third address sequence, which contains the high-order bits of the 10-bit address and the R/W bit set to ‘1’. After the third address sequence is performed, the UA bit is not set, the module is now configured in Transmit mode and clock stretching is controlled by the BF flag as in 7-Bit Slave Transmit mode (see Figure 21-13). Clock Stretching for 10-Bit Slave Receive Mode (SEN = 1) In 10-Bit Slave Receive mode, during the address sequence, clock stretching automatically takes place but CKP is not cleared. During this time, if the UA bit is set after the ninth clock, clock stretching is initiated. The UA bit is set after receiving the upper byte of the 10-bit address and following the receive of the second byte of the 10-bit address with the R/W bit cleared to ‘0’. The release of the clock line occurs upon updating SSPxADD. Clock stretching will occur on each data receive sequence as described in 7-bit mode. Note: If the user polls the UA bit and clears it by updating the SSPxADD register before the falling edge of the ninth clock occurs, and if the user hasn’t cleared the BF bit by reading the SSPxBUF register before that time, then the CKP bit will still NOT be asserted low. Clock stretching on the basis of the state of the BF bit only occurs during a data sequence, not an address sequence. DS39957B-page 326 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 21.4.4.5 Clock Synchronization and the CKP bit When the CKP bit is cleared, the SCLx output is forced to ‘0’. However, clearing the CKP bit will not assert the SCLx output low until the SCLx output is already sampled low. Therefore, the CKP bit will not assert the SCLx line until an external I2C master device has FIGURE 21-14: already asserted the SCLx line. The SCLx output will remain low until the CKP bit is set and all other devices on the I2C bus have deasserted SCLx. This ensures that a write to the CKP bit will not violate the minimum high time requirement for SCLx (see Figure 21-14). CLOCK SYNCHRONIZATION TIMING Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 SDAx DX – 1 DX SCLx CKP Master Device Asserts Clock Master Device Deasserts Clock WR SSPxCON1 2010 Microchip Technology Inc. Preliminary DS39957B-page 327 DS39957B-page 328 2 A6 Preliminary CKP (SSPxCON<4>) SSPOV (SSPxCON1<6>) BF (SSPxSTAT<0>) SSPxIF (PIR1<3> or PIR3<7>) 1 SCLx S A7 3 4 A4 5 A3 6 A2 Receiving Address A5 7 A1 8 9 ACK R/W = 0 3 4 D4 5 D3 Receiving Data D5 Cleared in software 2 D6 If BF is cleared prior to the falling edge of the 9th clock, CKP will not be reset to ‘0’ and no clock stretching will occur SSPxBUF is read 1 D7 6 D2 7 D1 9 ACK 1 D7 BF is set after falling edge of the 9th clock, CKP is reset to ‘0’ and clock stretching occurs 8 D0 3 4 D4 5 D3 Receiving Data D5 CKP written to ‘1’ in software 2 D6 Clock is held low until CKP is set to ‘1’ 6 D2 7 D1 8 D0 Bus master terminates transfer P SSPOV is set because SSPxBUF is still full. ACK is not sent. 9 ACK Clock is not held low because ACK = 1 FIGURE 21-15: SDAx Clock is not held low because buffer full bit is clear prior to falling edge of 9th clock PIC18F87K90 FAMILY I2C™ SLAVE MODE TIMING WITH SEN = 1 (RECEPTION, 7-BIT ADDRESS) 2010 Microchip Technology Inc. 2010 Microchip Technology Inc. 2 1 3 1 4 1 5 0 Preliminary CKP (SSPxCON<4>) UA (SSPxSTAT<1>) SSPOV (SSPxCON1<6>) BF (SSPxSTAT<0>) 6 7 A9 A8 8 UA is set indicating that the SSPxADD needs to be updated SSPxBUF is written with contents of SSPxSR Cleared in software SSPxIF (PIR1<3> or PIR3<7>) 1 SCLx S 1 9 ACK R/W = 0 A7 2 4 A4 5 A3 6 A2 Cleared in software 3 A5 7 A1 8 A0 Note: An update of the SSPxADD register before the falling edge of the ninth clock will have no effect on UA and UA will remain set. UA is set indicating that SSPxADD needs to be updated Cleared by hardware when SSPxADD is updated with low byte of address after falling edge of ninth clock Dummy read of SSPxBUF to clear BF flag 1 A6 Receive Second Byte of Address 9 ACK 2 4 5 6 Cleared in software 3 D3 D2 7 8 1 4 5 6 Cleared in software 3 CKP written to ‘1’ in software 2 D3 D2 Receive Data Byte D7 D6 D5 D4 Note: An update of the SSPxADD register before the falling edge of the ninth clock will have no effect on UA and UA will remain set. 9 ACK Clock is held low until CKP is set to ‘1’ D1 D0 Cleared by hardware when SSPxADD is updated with high byte of address after falling edge of ninth clock Dummy read of SSPxBUF to clear BF flag 1 D7 D6 D5 D4 Receive Data Byte Clock is held low until update of SSPxADD has taken place 7 8 9 Bus master terminates transfer P SSPOV is set because SSPxBUF is still full. ACK is not sent. D1 D0 ACK Clock is not held low because ACK = 1 FIGURE 21-16: SDAx Receive First Byte of Address Clock is held low until update of SSPxADD has taken place PIC18F87K90 FAMILY I2C™ SLAVE MODE TIMING WITH SEN = 1 (RECEPTION, 10-BIT ADDRESS) DS39957B-page 329 PIC18F87K90 FAMILY 21.4.5 GENERAL CALL ADDRESS SUPPORT If the general call address matches, the SSPxSR is transferred to the SSPxBUF, the BF flag bit is set (eighth bit), and on the falling edge of the ninth bit (ACK bit), the SSPxIF interrupt flag bit is set. The addressing procedure for the I2C bus is such that the first byte after the Start condition usually determines which device will be the slave addressed by the master. The exception is the general call address which can address all devices. When this address is used, all devices should, in theory, respond with an Acknowledge. When the interrupt is serviced, the source for the interrupt can be checked by reading the contents of the SSPxBUF. The value can be used to determine if the address was device-specific or a general call address. In 10-Bit Addressing mode, the SSPxADD is required to be updated for the second half of the address to match and the UA bit is set (SSPxSTAT<1>). If the general call address is sampled when the GCEN bit is set, while the slave is configured in 10-Bit Addressing mode, then the second half of the address is not necessary, the UA bit will not be set and the slave will begin receiving data after the Acknowledge (Figure 21-17). The general call address is one of eight addresses reserved for specific purposes by the I2C protocol. It consists of all ‘0’s with R/W = 0. The general call address is recognized when the General Call Enable bit, GCEN, is enabled (SSPxCON2<7> set). Following a Start bit detect, 8 bits are shifted into the SSPxSR and the address is compared against the SSPxADD. It is also compared to the general call address and fixed in hardware. FIGURE 21-17: SLAVE MODE GENERAL CALL ADDRESS SEQUENCE (7 OR 10-BIT ADDRESSING MODE) Address is Compared to General Call Address after ACK, set interrupt SCLx S 1 2 3 4 5 Receiving Data R/W = 0 General Call Address SDAx ACK D7 6 7 8 9 1 ACK D6 D5 D4 D3 D2 D1 D0 2 3 4 5 6 7 8 9 SSPxIF BF (SSPxSTAT<0>) Cleared in Software SSPxBUF is Read SSPOV (SSPxCON1<6>) ‘0’ GCEN (SSPxCON2<7>) ‘1’ DS39957B-page 330 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY MASTER MODE Note: Master mode is enabled by setting and clearing the appropriate SSPM bits in SSPxCON1 and by setting the SSPEN bit. In Master mode, the SCLx and SDAx lines are manipulated by the MSSP hardware if the TRIS bits are set. Master mode of operation is supported by interrupt generation on the detection of the Start and Stop conditions. The Stop (P) and Start (S) bits are cleared from a Reset or when the MSSP module is disabled. Control of the I 2C bus may be taken when the P bit is set, or the bus is Idle, with both the S and P bits clear. The following events will cause the MSSPx Interrupt Flag bit, SSPxIF, to be set (and MSSP interrupt, if enabled): In Firmware Controlled Master mode, user code conducts all I 2C bus operations based on Start and Stop bit conditions. • • • • • Once Master mode is enabled, the user has six options. 1. 2. 3. 4. 5. 6. Assert a Start condition on SDAx and SCLx. Assert a Repeated Start condition on SDAx and SCLx. Write to the SSPxBUF register initiating transmission of data/address. Configure the I2C port to receive data. Generate an Acknowledge condition at the end of a received byte of data. Generate a Stop condition on SDAx and SCLx. FIGURE 21-18: The MSSPx module, when configured in I2C Master mode, does not allow queueing of events. For instance, the user is not allowed to initiate a Start condition and immediately write the SSPxBUF register to initiate transmission before the Start condition is complete. In this case, the SSPxBUF will not be written to and the WCOL bit will be set, indicating that a write to the SSPxBUF did not occur. Start condition Stop condition Data transfer byte transmitted/received Acknowledge transmitted Repeated Start MSSP BLOCK DIAGRAM (I2C™ MASTER MODE) Internal Data Bus Read SSPM<3:0> SSPxADD<6:0> Write SSPxBUF SDAx Baud Rate Generator Shift Clock SDAx In SCLx In Bus Collision 2010 Microchip Technology Inc. LSb Start bit, Stop bit, Acknowledge Generate Start bit Detect Stop bit Detect Write Collision Detect Clock Arbitration State Counter for End of XMIT/RCV Preliminary Clock Cntl SCLx Receive Enable SSPxSR MSb Clock Arbitrate/WCOL Detect (hold off clock source) 21.4.6 Set/Reset S, P (SSPxSTAT), WCOL (SSPxCON1); Set SSPxIF, BCLxIF; Reset ACKSTAT, PEN (SSPxCON2) DS39957B-page 331 PIC18F87K90 FAMILY 21.4.6.1 I2C Master Mode Operation A typical transmit sequence would go as follows: The master device generates all of the serial clock pulses and the Start and Stop conditions. A transfer is ended with a Stop condition or with a Repeated Start condition. Since the Repeated Start condition is also the beginning of the next serial transfer, the I2C bus will not be released. In Master Transmitter mode, serial data is output through SDAx while SCLx outputs the serial clock. The first byte transmitted contains the slave address of the receiving device (7 bits) and the Read/Write (R/W) bit. In this case, the R/W bit will be logic ‘0’. Serial data is transmitted 8 bits at a time. After each byte is transmitted, an Acknowledge bit is received. Start and Stop conditions are output to indicate the beginning and the end of a serial transfer. In Master Receive mode, the first byte transmitted contains the slave address of the transmitting device (7 bits) and the R/W bit. In this case, the R/W bit will be logic ‘1’. Thus, the first byte transmitted is a 7-bit slave address, followed by a ‘1’ to indicate the receive bit. Serial data is received via SDAx, while SCLx outputs the serial clock. Serial data is received 8 bits at a time. After each byte is received, an Acknowledge bit is transmitted. Start and Stop conditions indicate the beginning and end of transmission. The Baud Rate Generator, used for the SPI mode operation, is used to set the SCLx clock frequency for either 100 kHz, 400 kHz or 1 MHz I2C operation. See Section 21.4.7 “Baud Rate” for more details. DS39957B-page 332 1. The user generates a Start condition by setting the Start Enable bit, SEN (SSPxCON2<0>). 2. SSPxIF is set. The MSSPx module will wait the required start time before any other operation takes place. 3. The user loads the SSPxBUF with the slave address to transmit. 4. Address is shifted out the SDAx pin until all 8 bits are transmitted. 5. The MSSPx module shifts in the ACK bit from the slave device and writes its value into the SSPxCON2 register (SSPxCON2<6>). 6. The MSSPx module generates an interrupt at the end of the ninth clock cycle by setting the SSPxIF bit. 7. The user loads the SSPxBUF with eight bits of data. 8. Data is shifted out the SDAx pin until all 8 bits are transmitted. 9. The MSSPx module shifts in the ACK bit from the slave device and writes its value into the SSPxCON2 register (SSPxCON2<6>). 10. The MSSPx module generates an interrupt at the end of the ninth clock cycle by setting the SSPxIF bit. 11. The user generates a Stop condition by setting the Stop Enable bit, PEN (SSPxCON2<2>). 12. Interrupt is generated once the Stop condition is complete. Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 21.4.7 BAUD RATE 21.4.7.1 2 In I C Master mode, the Baud Rate Generator (BRG) reload value is placed in the lower 7 bits of the SSPxADD register (Figure 21-19). When a write occurs to SSPxBUF, the Baud Rate Generator will automatically begin counting. The BRG counts down to 0 and stops until another reload has taken place. The BRG count is decremented twice per instruction cycle (TCY) on the Q2 and Q4 clocks. In I2C Master mode, the BRG is reloaded automatically. Baud Rate and Module Interdependence Because MSSP1 and MSSP2 are independent, they can operate simultaneously in I2C Master mode at different baud rates. This is done by using different BRG reload values for each module. Because this mode derives its basic clock source from the system clock, any changes to the clock will affect both modules in the same proportion. It may be possible to change one or both baud rates back to a previous value by changing the BRG reload value. Once the given operation is complete (i.e., transmission of the last data bit is followed by ACK), the internal clock will automatically stop counting and the SCLx pin will remain in its last state. Table 21-3 demonstrates clock rates based on instruction cycles and the BRG value loaded into SSPxADD. The SSPxADD BRG value of 0x00 is not supported. FIGURE 21-19: BAUD RATE GENERATOR BLOCK DIAGRAM SSPM<3:0> SSPM<3:0> SCLx SSPxADD<6:0> Reload Reload Control CLKO TABLE 21-3: BRG Down Counter FOSC/4 I2C™ CLOCK RATE w/BRG FOSC FCY FCY * 2 BRG Value FSCL (2 Rollovers of BRG) 40 MHz 10 MHz 20 MHz 18h 400 kHz(1) 40 MHz 10 MHz 20 MHz 1Fh 312.5 kHz 40 MHz 10 MHz 20 MHz 63h 100 kHz 16 MHz 4 MHz 8 MHz 09h 400 kHz(1) 16 MHz 4 MHz 8 MHz 0Ch 308 kHz 16 MHz 4 MHz 8 MHz 27h 100 kHz 4 MHz 1 MHz 2 MHz 02h 333 kHz(1) 4 MHz 1 MHz 2 MHz 09h 100 kHz 16 MHz(2) 4 MHz 8 MHz 03h 1 MHz(1) Note 1: 2: The I2C™ interface does not conform to the 400 kHz I2C specification (which applies to rates greater than 100 kHz) in all details, but may be used with care where higher rates are required by the application. A minimum of 16 MHz FOSC is required to get the 1 MHz I2C. 2010 Microchip Technology Inc. Preliminary DS39957B-page 333 PIC18F87K90 FAMILY 21.4.7.2 Clock Arbitration Clock arbitration occurs when the master, during any receive, transmit or Repeated Start/Stop condition, deasserts the SCLx pin (SCLx allowed to float high). When the SCLx pin is allowed to float high, the Baud Rate Generator (BRG) is suspended from counting until the SCLx pin is actually sampled high. When the FIGURE 21-20: SDAx SCLx pin is sampled high, the Baud Rate Generator is reloaded with the contents of SSPxADD<6:0> and begins counting. This ensures that the SCLx high time will always be at least one BRG rollover count in the event that the clock is held low by an external device (Figure 21-20). BAUD RATE GENERATOR TIMING WITH CLOCK ARBITRATION DX DX – 1 SCLx Deasserted but Slave Holds SCLx Low (clock arbitration) SCLx Allowed to Transition High SCLx BRG Decrements on Q2 and Q4 Cycles BRG Value 03h 02h 01h 00h (hold off) 03h 02h SCLx is Sampled High, Reload Takes Place and BRG Starts its Count BRG Reload DS39957B-page 334 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 21.4.8 I2C™ MASTER MODE START CONDITION TIMING Note: To initiate a Start condition, the user sets the Start Enable bit, SEN (SSPxCON2<0>). If the SDAx and SCLx pins are sampled high, the Baud Rate Generator is reloaded with the contents of SSPxADD<6:0> and starts its count. If SCLx and SDAx are both sampled high when the Baud Rate Generator times out (TBRG), the SDAx pin is driven low. The action of the SDAx being driven low while SCLx is high is the Start condition and causes the S bit (SSPxSTAT<3>) to be set. Following this, the Baud Rate Generator is reloaded with the contents of SSPxADD<6:0> and resumes its count. When the Baud Rate Generator times out (TBRG), the SEN bit (SSPxCON2<0>) will be automatically cleared by hardware. The Baud Rate Generator is suspended, leaving the SDAx line held low and the Start condition is complete. FIGURE 21-21: 21.4.8.1 If, at the beginning of the Start condition, the SDAx and SCLx pins are already sampled low or if during the Start condition, the SCLx line is sampled low before the SDAx line is driven low, a bus collision occurs, the Bus Collision Interrupt Flag, BCLxIF, is set, the Start condition is aborted and the I2C module is reset into its Idle state. WCOL Status Flag If the user writes the SSPxBUF when a Start sequence is in progress, the WCOL bit is set and the contents of the buffer are unchanged (the write doesn’t occur). Note: Because queueing of events is not allowed, writing to the lower 5 bits of SSPxCON2 is disabled until the Start condition is complete. FIRST START BIT TIMING Write to SEN bit Occurs Here Set S bit (SSPxSTAT<3>) SDAx = 1, SCLx = 1 TBRG At Completion of Start bit, Hardware Clears SEN bit and Sets SSPxIF bit TBRG Write to SSPxBUF Occurs Here 1st bit SDAx 2nd bit TBRG SCLx TBRG S 2010 Microchip Technology Inc. Preliminary DS39957B-page 335 PIC18F87K90 FAMILY 21.4.9 I2C™ MASTER MODE REPEATED START CONDITION TIMING Note 1: If RSEN is programmed while any other event is in progress, it will not take effect. A Repeated Start condition occurs when the RSEN bit (SSPxCON2<1>) is programmed high and the I2C logic module is in the Idle state. When the RSEN bit is set, the SCLx pin is asserted low. When the SCLx pin is sampled low, the Baud Rate Generator is loaded with the contents of SSPxADD<5:0> and begins counting. The SDAx pin is released (brought high) for one Baud Rate Generator count (TBRG). When the Baud Rate Generator times out, and if SDAx is sampled high, the SCLx pin will be deasserted (brought high). When SCLx is sampled high, the Baud Rate Generator is reloaded with the contents of SSPxADD<6:0> and begins counting. SDAx and SCLx must be sampled high for one TBRG. This action is then followed by assertion of the SDAx pin (SDAx = 0) for one TBRG while SCLx is high. Following this, the RSEN bit (SSPxCON2<1>) will be automatically cleared and the Baud Rate Generator will not be reloaded, leaving the SDAx pin held low. As soon as a Start condition is detected on the SDAx and SCLx pins, the S bit (SSPxSTAT<3>) will be set. The SSPxIF bit will not be set until the Baud Rate Generator has timed out. 2: A bus collision during the Repeated Start condition occurs if: • SDAx is sampled low when SCLx goes from low-to-high. • SCLx goes low before SDAx is asserted low. This may indicate that another master is attempting to transmit a data ‘1’. Immediately following the SSPxIF bit getting set, the user may write the SSPxBUF with the 7-bit address in 7-bit mode or the default first address in 10-bit mode. After the first eight bits are transmitted and an ACK is received, the user may then transmit an additional eight bits of address (10-bit mode) or eight bits of data (7-bit mode). 21.4.9.1 If the user writes the SSPxBUF when a Repeated Start sequence is in progress, the WCOL is set and the contents of the buffer are unchanged (the write doesn’t occur). Note: FIGURE 21-22: WCOL Status Flag Because queueing of events is not allowed, writing of the lower 5 bits of SSPxCON2 is disabled until the Repeated Start condition is complete. REPEATED START CONDITION WAVEFORM S bit Set by Hardware Write to SSPxCON2 Occurs Here: SDAx = 1, SCLx (no change). SDAx = 1, SCLx = 1 TBRG TBRG At Completion of Start bit, Hardware Clears RSEN bit and Sets SSPxIF TBRG 1st bit SDAx RSEN bit Set by Hardware on Falling Edge of Ninth Clock, End of XMIT Write to SSPxBUF Occurs Here TBRG SCLx TBRG Sr = Repeated Start DS39957B-page 336 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 21.4.10 I2C™ MASTER MODE TRANSMISSION Transmission of a data byte, a 7-bit address or the other half of a 10-bit address, is accomplished by simply writing a value to the SSPxBUF register. This action will set the Buffer Full flag bit, BF, and allow the Baud Rate Generator to begin counting and start the next transmission. Each bit of address/data will be shifted out onto the SDAx pin after the falling edge of SCLx is asserted (see data hold time specification parameter 106). SCLx is held low for one Baud Rate Generator rollover count (TBRG). Data should be valid before SCLx is released high (see data setup time specification parameter 107). When the SCLx pin is released high, it is held that way for TBRG. The data on the SDAx pin must remain stable for that duration and some hold time after the next falling edge of SCLx. After the eighth bit is shifted out (the falling edge of the eighth clock), the BF flag is cleared and the master releases SDAx. This allows the slave device being addressed to respond with an ACK bit during the ninth bit time if an address match occurred, or if data was received properly. The status of ACK is written into the ACKDT bit on the falling edge of the ninth clock. If the master receives an Acknowledge, the Acknowledge Status bit, ACKSTAT, is cleared; if not, the bit is set. After the ninth clock, the SSPxIF bit is set and the master clock (Baud Rate Generator) is suspended until the next data byte is loaded into the SSPxBUF, leaving SCLx low and SDAx unchanged (Figure 21-23). After the write to the SSPxBUF, each bit of the address will be shifted out on the falling edge of SCLx until all seven address bits and the R/W bit are completed. On the falling edge of the eighth clock, the master will deassert the SDAx pin, allowing the slave to respond with an Acknowledge. On the falling edge of the ninth clock, the master will sample the SDAx pin to see if the address was recognized by a slave. The status of the ACK bit is loaded into the ACKSTAT status bit (SSPxCON2<6>). Following the falling edge of the ninth clock transmission of the address, the SSPxIF flag is set, the BF flag is cleared and the Baud Rate Generator is turned off until another write to the SSPxBUF takes place, holding SCLx low and allowing SDAx to float. 21.4.10.1 BF Status Flag In Transmit mode, the BF bit (SSPxSTAT<0>) is set when the CPU writes to SSPxBUF and is cleared when all 8 bits are shifted out. 21.4.10.2 WCOL Status Flag If the user writes the SSPxBUF when a transmit is already in progress (i.e., SSPxSR is still shifting out a data byte), the WCOL bit is set and the contents of the buffer are unchanged (the write doesn’t occur) after 2010 Microchip Technology Inc. 2 TCY after the SSPxBUF write. If SSPxBUF is rewritten within 2 TCY, the WCOL bit is set and SSPxBUF is updated. This may result in a corrupted transfer. The user should verify that the WCOL bit is clear after each write to SSPxBUF to ensure the transfer is correct. In all cases, WCOL must be cleared in software. 21.4.10.3 ACKSTAT Status Flag In Transmit mode, the ACKSTAT bit (SSPxCON2<6>) is cleared when the slave has sent an Acknowledge (ACK = 0) and is set when the slave does not Acknowledge (ACK = 1). A slave sends an Acknowledge when it has recognized its address (including a general call), or when the slave has properly received its data. 21.4.11 I2C MASTER MODE RECEPTION Master mode reception is enabled by programming the Receive Enable bit, RCEN (SSPxCON2<3>). Note: The MSSP module must be in an inactive state before the RCEN bit is set or the RCEN bit will be disregarded. The Baud Rate Generator begins counting, and on each rollover, the state of the SCLx pin changes (high-to-low/low-to-high) and data is shifted into the SSPxSR. After the falling edge of the eighth clock, the receive enable flag is automatically cleared, the contents of the SSPxSR are loaded into the SSPxBUF, the BF flag bit is set, the SSPxIF flag bit is set and the Baud Rate Generator is suspended from counting, holding SCLx low. The MSSP is now in Idle state awaiting the next command. When the buffer is read by the CPU, the BF flag bit is automatically cleared. The user can then send an Acknowledge bit at the end of reception by setting the Acknowledge Sequence Enable bit, ACKEN (SSPxCON2<4>). 21.4.11.1 BF Status Flag In receive operation, the BF bit is set when an address or data byte is loaded into SSPxBUF from SSPxSR. It is cleared when the SSPxBUF register is read. 21.4.11.2 SSPOV Status Flag In receive operation, the SSPOV bit is set when 8 bits are received into the SSPxSR and the BF flag bit is already set from a previous reception. 21.4.11.3 WCOL Status Flag If the user writes the SSPxBUF when a receive is already in progress (i.e., SSPxSR is still shifting in a data byte), the WCOL bit is set and the contents of the buffer are unchanged (the write doesn’t occur). Preliminary DS39957B-page 337 DS39957B-page 338 S Preliminary R/W PEN SEN BF (SSPxSTAT<0>) SSPxIF SCLx SDAx A6 A5 A4 A3 A2 A1 3 4 5 Cleared in software 2 6 7 8 After Start condition, SEN cleared by hardware SSPxBUF written 1 9 D7 1 SCLx held low while CPU responds to SSPxIF ACK = 0 R/W = 0 SSPxBUF written with 7-bit address and R/W, start transmit A7 Transmit Address to Slave 3 D5 4 D4 5 D3 6 D2 7 D1 8 D0 SSPxBUF is written in software Cleared in software service routine from MSSP interrupt 2 D6 Transmitting Data or Second Half of 10-bit Address P Cleared in software 9 ACK From slave, clear ACKSTAT bit (SSPxCON2<6>) ACKSTAT in SSPxCON2 = 1 FIGURE 21-23: SEN = 0 Write SSPxCON2<0> (SEN = 1), Start condition begins PIC18F87K90 FAMILY I 2C™ MASTER MODE WAVEFORM (TRANSMISSION, 7 OR 10-BIT ADDRESS) 2010 Microchip Technology Inc. 2010 Microchip Technology Inc. S Preliminary ACKEN SSPOV BF (SSPxSTAT<0>) SDAx = 0, SCLx = 1, while CPU responds to SSPxIF SSPxIF SCLx SDAx 1 A7 2 4 5 6 Cleared in software 3 A6 A5 A4 A3 A2 Transmit Address to Slave 7 A1 8 9 R/W = 1 ACK Receiving Data from Slave 2 3 5 6 7 8 D0 9 ACK Receiving Data from Slave 2 3 4 5 6 7 Cleared in software Set SSPxIF interrupt at end of Acknowledge sequence Data shifted in on falling edge of CLK 1 Cleared in software Set SSPxIF at end of receive 9 ACK is not sent ACK Bus master terminates transfer Set P bit (SSPxSTAT<4>) and SSPxIF Set SSPxIF interrupt at end of Acknowledge sequence P PEN bit = 1 written here SSPOV is set because SSPxBUF is still full 8 D0 RCEN cleared automatically Set ACKEN, start Acknowledge sequence, SDAx = ACKDT = 1 D7 D6 D5 D4 D3 D2 D1 Last bit is shifted into SSPxSR and contents are unloaded into SSPxBUF Cleared in software Set SSPxIF interrupt at end of receive 4 Cleared in software 1 D7 D6 D5 D4 D3 D2 D1 RCEN = 1, start next receive ACK from master, SDAx = ACKDT = 0 FIGURE 21-24: Master configured as a receiver by programming SSPxCON2<3> (RCEN = 1) SEN = 0 Write to SSPxBUF occurs here, RCEN cleared ACK from Slave automatically start XMIT Write to SSPxCON2<0> (SEN = 1), begin Start condition Write to SSPxCON2<4> to start Acknowledge sequence, SDAx = ACKDT (SSPxCON2<5>) = 0 PIC18F87K90 FAMILY I 2C™ MASTER MODE WAVEFORM (RECEPTION, 7-BIT ADDRESS) DS39957B-page 339 PIC18F87K90 FAMILY 21.4.12 ACKNOWLEDGE SEQUENCE TIMING 21.4.13 A Stop bit is asserted on the SDAx pin at the end of a receive/transmit by setting the Stop Sequence Enable bit, PEN (SSPxCON2<2>). At the end of a receive/transmit, the SCLx line is held low after the falling edge of the ninth clock. When the PEN bit is set, the master will assert the SDAx line low. When the SDAx line is sampled low, the Baud Rate Generator is reloaded and counts down to 0. When the Baud Rate Generator times out, the SCLx pin will be brought high and one TBRG (Baud Rate Generator rollover count) later, the SDAx pin will be deasserted. When the SDAx pin is sampled high while SCLx is high, the P bit (SSPxSTAT<4>) is set. A TBRG later, the PEN bit is cleared and the SSPxIF bit is set (Figure 21-26). An Acknowledge sequence is enabled by setting the Acknowledge Sequence Enable bit, ACKEN (SSPxCON2<4>). When this bit is set, the SCLx pin is pulled low and the contents of the Acknowledge data bit are presented on the SDAx pin. If the user wishes to generate an Acknowledge, then the ACKDT bit should be cleared. If not, the user should set the ACKDT bit before starting an Acknowledge sequence. The Baud Rate Generator then counts for one rollover period (TBRG) and the SCLx pin is deasserted (pulled high). When the SCLx pin is sampled high (clock arbitration), the Baud Rate Generator counts for TBRG; the SCLx pin is then pulled low. Following this, the ACKEN bit is automatically cleared, the Baud Rate Generator is turned off and the MSSP module then goes into an inactive state (Figure 21-25). 21.4.12.1 21.4.13.1 WCOL Status Flag If the user writes the SSPxBUF when a Stop sequence is in progress, then the WCOL bit is set and the contents of the buffer are unchanged (the write doesn’t occur). WCOL Status Flag If the user writes the SSPxBUF when an Acknowledge sequence is in progress, then WCOL is set and the contents of the buffer are unchanged (the write doesn’t occur). FIGURE 21-25: STOP CONDITION TIMING ACKNOWLEDGE SEQUENCE WAVEFORM Acknowledge Sequence Starts Here, Write to SSPxCON2, ACKEN = 1, ACKDT = 0 SDAx D0 SCLx 8 ACKEN Automatically Cleared TBRG TBRG ACK 9 SSPxIF SSPxIF Set at the End of Receive Cleared in Software SSPxIF Set at the End of Acknowledge Sequence Cleared in Software Note: TBRG = one Baud Rate Generator period. FIGURE 21-26: STOP CONDITION RECEIVE OR TRANSMIT MODE SCLx = 1 for TBRG, Followed by SDAx = 1 for TBRG After SDAx Sampled High. P bit (SSPxSTAT<4>) is Set. Write to SSPxCON2, Set PEN PEN bit (SSPxCON2<2>) is Cleared by Hardware and the SSPxIF bit is Set Falling Edge of 9th Clock TBRG SCLx SDAx ACK P TBRG TBRG TBRG SCLx Brought High After TBRG SDAx Asserted Low Before Rising Edge of Clock to Set Up Stop Condition Note: TBRG = one Baud Rate Generator period. DS39957B-page 340 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 21.4.14 SLEEP OPERATION 21.4.17 2 While in Sleep mode, the I C module can receive addresses or data and when an address match or complete byte transfer occurs, wake the processor from Sleep (if the MSSP interrupt is enabled). 21.4.15 EFFECTS OF A RESET A Reset disables the MSSP module and terminates the current transfer. 21.4.16 MULTI-MASTER MODE In Multi-Master mode, the interrupt generation on the detection of the Start and Stop conditions allows the determination of when the bus is free. The Stop (P) and Start (S) bits are cleared from a Reset or when the MSSP module is disabled. Control of the I 2C bus may be taken when the P bit (SSPxSTAT<4>) is set, or the bus is Idle, with both the S and P bits clear. When the bus is busy, enabling the MSSP interrupt will generate the interrupt when the Stop condition occurs. In multi-master operation, the SDAx line must be monitored for arbitration to see if the signal level is the expected output level. This check is performed in hardware with the result placed in the BCLxIF bit. The states where arbitration can be lost are: • • • • • Address Transfer Data Transfer A Start Condition A Repeated Start Condition An Acknowledge Condition MULTI -MASTER COMMUNICATION, BUS COLLISION AND BUS ARBITRATION Multi-Master mode support is achieved by bus arbitration. When the master outputs address/data bits onto the SDAx pin, arbitration takes place when the master outputs a ‘1’ on SDAx, by letting SDAx float high, and another master asserts a ‘0’. When the SCLx pin floats high, data should be stable. If the expected data on SDAx is a ‘1’ and the data sampled on the SDAx pin = 0, then a bus collision has taken place. The master will set the Bus Collision Interrupt Flag, BCLxIF, and reset the I2C port to its Idle state (Figure 21-27). If a transmit was in progress when the bus collision occurred, the transmission is halted, the BF flag is cleared, the SDAx and SCLx lines are deasserted and the SSPxBUF can be written to. When the user services the bus collision Interrupt Service Routine and if the I2C bus is free, the user can resume communication by asserting a Start condition. If a Start, Repeated Start, Stop or Acknowledge condition was in progress when the bus collision occurred, the condition is aborted, the SDAx and SCLx lines are deasserted and the respective control bits in the SSPxCON2 register are cleared. When the user services the bus collision Interrupt Service Routine, and if the I2C bus is free, the user can resume communication by asserting a Start condition. The master will continue to monitor the SDAx and SCLx pins. If a Stop condition occurs, the SSPxIF bit will be set. A write to the SSPxBUF will start the transmission of data at the first data bit regardless of where the transmitter left off when the bus collision occurred. In Multi-Master mode, the interrupt generation on the detection of Start and Stop conditions allows the determination of when the bus is free. Control of the I2C bus can be taken when the P bit is set in the SSPxSTAT register, or the bus is Idle and the S and P bits are cleared. FIGURE 21-27: BUS COLLISION TIMING FOR TRANSMIT AND ACKNOWLEDGE Data Changes while SCLx = 0 SDAx Line Pulled Low by Another Source SDAx Released by Master Sample SDAx. While SCLx is High, Data Doesn’t Match what is Driven by the Master; Bus Collision has Occurred. SDAx SCLx Set Bus Collision Interrupt (BCLxIF) BCLxIF 2010 Microchip Technology Inc. Preliminary DS39957B-page 341 PIC18F87K90 FAMILY 21.4.17.1 Bus Collision During a Start Condition During a Start condition, a bus collision occurs if: a) b) SDAx or SCLx is sampled low at the beginning of the Start condition (Figure 21-28). SCLx is sampled low before SDAx is asserted low (Figure 21-29). During a Start condition, both the SDAx and the SCLx pins are monitored. If the SDAx pin is sampled low during this count, the BRG is reset and the SDAx line is asserted early (Figure 21-30). If, however, a ‘1’ is sampled on the SDAx pin, the SDAx pin is asserted low at the end of the BRG count. The Baud Rate Generator is then reloaded and counts down to 0. If the SCLx pin is sampled as ‘0’ during this time, a bus collision does not occur. At the end of the BRG count, the SCLx pin is asserted low. Note: If the SDAx pin is already low, or the SCLx pin is already low, then all of the following occur: • the Start condition is aborted, • the BCLxIF flag is set and • the MSSP module is reset to its inactive state (Figure 21-28) The Start condition begins with the SDAx and SCLx pins deasserted. When the SDAx pin is sampled high, the Baud Rate Generator is loaded from SSPxADD<6:0> and counts down to 0. If the SCLx pin is sampled low while SDAx is high, a bus collision occurs because it is assumed that another master is attempting to drive a data ‘1’ during the Start condition. FIGURE 21-28: The reason that bus collision is not a factor during a Start condition is that no two bus masters can assert a Start condition at the exact same time. Therefore, one master will always assert SDAx before the other. This condition does not cause a bus collision because the two masters must be allowed to arbitrate the first address following the Start condition. If the address is the same, arbitration must be allowed to continue into the data portion, Repeated Start or Stop conditions. BUS COLLISION DURING START CONDITION (SDAx ONLY) SDAx goes Low Before the SEN bit is Set. Set BCLxIF, S bit and SSPxIF Set because SDAx = 0, SCLx = 1. SDAx SCLx Set SEN, Enable Start Condition if SDAx = 1, SCLx = 1 SEN Cleared Automatically because of Bus Collision. MSSP module Reset into Idle State. SEN BCLxIF SDAx Sampled Low before Start Condition. Set BCLxIF. S bit and SSPxIF Set because SDAx = 0, SCLx = 1. SSPxIF and BCLxIF are Cleared in Software S SSPxIF SSPxIF and BCLxIF are Cleared in Software DS39957B-page 342 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY FIGURE 21-29: BUS COLLISION DURING START CONDITION (SCLx = 0) SDAx = 0, SCLx = 1 TBRG TBRG SDAx Set SEN, Enable Start Sequence if SDAx = 1, SCLx = 1 SCLx SCLx = 0 before SDAx = 0, Bus Collision Occurs. Set BCLxIF. SEN SCLx = 0 before BRG Time-out, Bus Collision Occurs. Set BCLxIF. BCLxIF Interrupt Cleared in Software S ‘0’ ‘0’ SSPxIF ‘0’ ‘0’ FIGURE 21-30: BRG RESET DUE TO SDAx ARBITRATION DURING START CONDITION SDAx = 0, SCLx = 1 Set S Less than TBRG SDAx Set SSPxIF TBRG SDAx Pulled Low by Other Master. Reset BRG and Assert SDAx. SCLx S SCLx Pulled Low After BRG Time-out SEN Set SEN, Enable Start Sequence if SDAx = 1, SCLx = 1 BCLxIF ‘0’ S SSPxIF SDAx = 0, SCLx = 1, Set SSPxIF 2010 Microchip Technology Inc. Preliminary Interrupts Cleared in Software DS39957B-page 343 PIC18F87K90 FAMILY 21.4.17.2 Bus Collision During a Repeated Start Condition If SDAx is low, a bus collision has occurred (i.e., another master is attempting to transmit a data ‘0’, Figure 21-31). If SDAx is sampled high, the BRG is reloaded and begins counting. If SDAx goes from high-to-low before the BRG times out, no bus collision occurs because no two masters can assert SDAx at exactly the same time. During a Repeated Start condition, a bus collision occurs if: a) b) A low level is sampled on SDAx when SCLx goes from a low level to a high level. SCLx goes low before SDAx is asserted low, indicating that another master is attempting to transmit a data ‘1’. If SCLx goes from high-to-low before the BRG times out and SDAx has not already been asserted, a bus collision occurs. In this case, another master is attempting to transmit a data ‘1’ during the Repeated Start condition (see Figure 21-32). When the user deasserts SDAx and the pin is allowed to float high, the BRG is loaded with SSPxADD<6:0> and counts down to 0. The SCLx pin is then deasserted and when sampled high, the SDAx pin is sampled. FIGURE 21-31: If, at the end of the BRG time-out, both SCLx and SDAx are still high, the SDAx pin is driven low and the BRG is reloaded and begins counting. At the end of the count, regardless of the status of the SCLx pin, the SCLx pin is driven low and the Repeated Start condition is complete. BUS COLLISION DURING A REPEATED START CONDITION (CASE 1) SDAx SCLx Sample SDAx when SCLx goes High. If SDAx = 0, Set BCLxIF and Release SDAx and SCLx. RSEN BCLxIF Cleared in Software ‘0’ S ‘0’ SSPxIF FIGURE 21-32: BUS COLLISION DURING REPEATED START CONDITION (CASE 2) TBRG TBRG SDAx SCLx BCLxIF SCLx goes Low Before SDAx, Set BCLxIF. Release SDAx and SCLx. Interrupt Cleared in Software RSEN ‘0’ S SSPxIF DS39957B-page 344 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 21.4.17.3 Bus Collision During a Stop Condition The Stop condition begins with SDAx asserted low. When SDAx is sampled low, the SCLx pin is allowed to float. When the pin is sampled high (clock arbitration), the Baud Rate Generator is loaded with SSPxADD<6:0> and counts down to 0. After the BRG times out, SDAx is sampled. If SDAx is sampled low, a bus collision has occurred. This is due to another master attempting to drive a data ‘0’ (Figure 21-33). If the SCLx pin is sampled low before SDAx is allowed to float high, a bus collision occurs. This is another case of another master attempting to drive a data ‘0’ (Figure 21-34). Bus collision occurs during a Stop condition if: a) b) After the SDAx pin has been deasserted and allowed to float high, SDAx is sampled low after the BRG has timed out. After the SCLx pin is deasserted, SCLx is sampled low before SDAx goes high. FIGURE 21-33: BUS COLLISION DURING A STOP CONDITION (CASE 1) TBRG TBRG TBRG SDAx SDAx Sampled Low After TBRG, Set BCLxIF SDAx Asserted Low SCLx PEN BCLxIF P ‘0’ SSPxIF ‘0’ FIGURE 21-34: BUS COLLISION DURING A STOP CONDITION (CASE 2) TBRG TBRG TBRG SDAx SCLx goes Low Before SDAx goes High, Set BCLxIF Assert SDAx SCLx PEN BCLxIF P ‘0’ SSPxIF ‘0’ 2010 Microchip Technology Inc. Preliminary DS39957B-page 345 PIC18F87K90 FAMILY TABLE 21-4: Name INTCON REGISTERS ASSOCIATED WITH I2C™ OPERATION Bit 7 Bit 6 GIE/GIEH PEIE/GIEL Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Reset Values on Page: TMR0IE INT0IE RBIE TMR0IF INT0IF RBIF 73 PIR1 — ADIF RC1IF TX1IF SSP1IF TMR1GIF TMR2IF TMR1IF 75 PIE1 — ADIE RC1IE TX1IE SSP1IE TMR1GIE TMR2IE TMR1IE 75 IPR1 — ADIP RC1IP TX1IP SSP1IP TMR1GIP TMR2IP TMR1IP 75 PIR2 OSCFIF — SSP2IF BLC2IF BCL1IF HLVDIF TMR3IF TMR3GIF 75 PIE2 OSCFIE — SSP2IE BLC2IE BCL1IE HLVDIE TMR3IE TMR3GIE 75 IPR2 OSCFIP — SSP2IP BLC2IP BCL1IP HLVDIP TMR3IP TMR3GIP 75 PIR3 TMR5GIF LCDIF RC2IF TX2IF CTMUIF CCP2IF CCP1IF RTCCIF 75 PIE3 TMR5GIE LCDIE RC2IE TX2IE CTMUIE CCP2IE CCP1IE RTCCIE 75 IPR3 TMR5GIP LCDIP RC2IP TX2IP CTMUIP CCP2IP CCP1IP RTCCIP 75 TRISC7 TRISC6 TRISC5 TRISC4 TRISC3 TRISC2 TRISC1 TRISC0 76 TRISD7 TRISD6 TRISD5 TRISD4 TRISD3 TRISD2 TRISD1 TRISD0 76 TRISC TRISD SSP1BUF SSP1ADD MSSP1 Receive Buffer/Transmit Register 74 2C™ Slave mode), MSSP1 Address Register (I MSSP1 Baud Rate Reload Register (I2C Master mode) 74 SSP1MSK(1) MSK7 MSK6 MSK5 MSK4 MSK3 MSK2 MSK1 MSK0 — SSP1CON1 WCOL SSPOV SSPEN CKP SSPM3 SSPM2 SSPM1 SSPM0 74 GCEN ACKSTAT ACKDT ACKEN RCEN PEN RSEN GCEN ACKSTAT ADMSK5(2) ADMSK4(2) ADMSK3(2) ADMSK2(2) ADMSK1(2) SSP1CON2 SSP1STAT SMP CKE D/A P S R/W SEN UA SEN BF 74 74 SSP2BUF MSSP2 Receive Buffer/Transmit Register 80 SSP2ADD MSSP2 Address Register (I2C Slave mode), MSSP2 Baud Rate Reload Register (I2C Master mode) 80 SSP2MSK(1) MSK7 SSP2CON1 SSP2CON2 SSP2STAT MSK6 MSK5 WCOL SSPOV GCEN ACKSTAT GCEN ACKSTAT ADMSK5(2) ADMSK4(2) ADMSK3(2) ADMSK2(2) ADMSK1(2) SMP CKE MSK4 MSK3 MSK2 MSK1 MSK0 — SSPEN CKP SSPM3 SSPM2 SSPM1 SSPM0 80 ACKDT ACKEN RCEN PEN RSEN SEN D/A P S R/W UA SEN BF 81 80 2 Legend: — = unimplemented, read as ‘0’. Shaded cells are not used by the MSSP module in I C™ mode. Note 1: SSPxMSK shares the same address in SFR space as SSPxADD, but is only accessible in certain I2C™ Slave operating modes in 7-Bit Masking mode. See Section 21.4.3.4 “7-Bit Address Masking Mode” for more details. 2: Alternate bit definitions for use in I2C Slave mode operations only. DS39957B-page 346 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 22.0 ENHANCED UNIVERSAL SYNCHRONOUS ASYNCHRONOUS RECEIVER TRANSMITTER (EUSART) The Enhanced Universal Synchronous Asynchronous Receiver Transmitter (EUSART) module is one of two serial I/O modules. (Generically, the EUSART is also known as a Serial Communications Interface or SCI.) The EUSART can be configured as a full-duplex, asynchronous system that can communicate with peripheral devices, such as CRT terminals and personal computers. It can also be configured as a half-duplex synchronous system that can communicate with peripheral devices, such as A/D or D/A integrated circuits, serial EEPROMs, etc. The Enhanced USART module implements additional features, including automatic baud rate detection and calibration, automatic wake-up on Sync Break reception and 12-bit Break character transmit. These make it ideally suited for use in Local Interconnect Network bus (LIN/J2602 bus) systems. All members of the PIC18F87K90 family are equipped with two independent EUSART modules, referred to as EUSART1 and EUSART2. They can be configured in the following modes: • Asynchronous (full duplex) with: - Auto-wake-up on character reception - Auto-baud calibration - 12-bit Break character transmission • Synchronous – Master (half duplex) with selectable clock polarity • Synchronous – Slave (half duplex) with selectable clock polarity 2010 Microchip Technology Inc. The pins of EUSART1 and EUSART2 are multiplexed with the functions of PORTC (RC6/TX1/CK1/ SEG27 and RC7/RX1/DT1/SEG28) and PORTG (RG1/TX2/CK2/AN19/C3OUT and RG2/RX2/DT2/ AN18/C3INA), respectively. In order to configure these pins as an EUSART: • For EUSART1: - SPEN (RCSTA1<7>) bit must be set (= 1) - TRISC<7> bit must be set (= 1) - TRISC<6> bit must be cleared (= 0) for Asynchronous and Synchronous Master modes - TRISC<6> bit must be set (= 1) for Synchronous Slave mode • For EUSART2: - SPEN (RCSTA2<7>) bit must be set (= 1) - TRISG<2> bit must be set (= 1) - TRISG<1> bit must be cleared (= 0) for Asynchronous and Synchronous Master modes - TRISC<6> bit must be set (= 1) for Synchronous Slave mode Note: The EUSART control will automatically reconfigure the pin from input to output as needed. The operation of each Enhanced USART module is controlled through three registers: • Transmit Status and Control (TXSTAx) • Receive Status and Control (RCSTAx) • Baud Rate Control (BAUDCONx) These are detailed in Register 22-1, Register 22-2 and Register 22-3, respectively, on the following pages. Note: Preliminary Throughout this section, references to register and bit names that may be associated with a specific EUSART module are referred to generically by the use of ‘x’ in place of the specific module number. Thus, “RCSTAx” might refer to the Receive Status register for either EUSART1 or EUSART2. DS39957B-page 347 PIC18F87K90 FAMILY REGISTER 22-1: TXSTAx: TRANSMIT STATUS AND CONTROL REGISTER R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R-1 R/W-0 CSRC TX9 TXEN(1) SYNC SENDB BRGH TRMT TX9D bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 CSRC: Clock Source Select bit Asynchronous mode: Don’t care. Synchronous mode: 1 = Master mode (clock generated internally from BRG) 0 = Slave mode (clock from external source) bit 6 TX9: 9-Bit Transmit Enable bit 1 = Selects 9-bit transmission 0 = Selects 8-bit transmission bit 5 TXEN: Transmit Enable bit(1) 1 = Transmit is enabled 0 = Transmit isndisabled bit 4 SYNC: EUSART Mode Select bit 1 = Synchronous mode 0 = Asynchronous mode bit 3 SENDB: Send Break Character bit Asynchronous mode: 1 = Send Sync Break on next transmission (cleared by hardware upon completion) 0 = Sync Break transmission has completed Synchronous mode: Don’t care. bit 2 BRGH: High Baud Rate Select bit Asynchronous mode: 1 = High speed 0 = Low speed Synchronous mode: Unused in this mode. bit 1 TRMT: Transmit Shift Register Status bit 1 = TSR is empty 0 = TSR is full bit 0 TX9D: 9th bit of Transmit Data Can be an address/data bit or a parity bit. Note 1: SREN/CREN overrides TXEN in Sync mode. DS39957B-page 348 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY REGISTER 22-2: RCSTAx: RECEIVE STATUS AND CONTROL REGISTER R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R-0 R-0 R-x SPEN RX9 SREN CREN ADDEN FERR OERR RX9D bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 SPEN: Serial Port Enable bit 1 = Serial port is enabled 0 = Serial is port disabled (held in Reset) bit 6 RX9: 9-Bit Receive Enable bit 1 = Selects 9-bit reception 0 = Selects 8-bit reception bit 5 SREN: Single Receive Enable bit Asynchronous mode: Don’t care. Synchronous mode – Master: 1 = Enables single receive 0 = Disables single receive This bit is cleared after reception is complete. Synchronous mode – Slave: Don’t care. bit 4 CREN: Continuous Receive Enable bit Asynchronous mode: 1 = Enables the receiver 0 = Disables the receiver Synchronous mode: 1 = Enables continuous receive until enable bit, CREN, is cleared (CREN overrides SREN) 0 = Disables continuous receive bit 3 ADDEN: Address Detect Enable bit Asynchronous mode 9-Bit (RX9 = 1): 1 = Enables address detection, enables interrupt and loads the receive buffer when RSR<8> is set 0 = Disables address detection, all bytes are received and ninth bit can be used as parity bit Asynchronous mode 9-Bit (RX9 = 0): Don’t care. bit 2 FERR: Framing Error bit 1 = Framing error (can be cleared by reading the RCREGx register and receiving the next valid byte) 0 = No framing error bit 1 OERR: Overrun Error bit 1 = Overrun error (can be cleared by clearing bit, CREN) 0 = No overrun error bit 0 RX9D: 9th bit of Received Data This can be an address/data bit or a parity bit and must be calculated by user firmware. 2010 Microchip Technology Inc. Preliminary DS39957B-page 349 PIC18F87K90 FAMILY REGISTER 22-3: BAUDCONx: BAUD RATE CONTROL REGISTER R/W-0 R-1 R/W-0 R/W-0 R/W-0 U-0 R/W-0 R/W-0 ABDOVF RCIDL RXDTP TXCKP BRG16 — WUE ABDEN bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 ABDOVF: Auto-Baud Acquisition Rollover Status bit 1 = A BRG rollover has occurred during Auto-Baud Rate Detect mode (must be cleared in software) 0 = No BRG rollover has occurred bit 6 RCIDL: Receive Operation Idle Status bit 1 = Receive operation is Idle 0 = Receive operation is active bit 5 RXDTP: Data/Receive Polarity Select bit Asynchronous mode: 1 = Receive data (RXx) is inverted (active-low) 0 = Receive data (RXx) is not inverted (active-high) Synchronous mode: 1 = Data (DTx) is inverted (active-low) 0 = Data (DTx) is not inverted (active-high) bit 4 TXCKP: Synchronous Clock Polarity Select bit Asynchronous mode: 1 = Idle state for transmit (TXx) is a low level 0 = Idle state for transmit (TXx) is a high level Synchronous mode: 1 = Idle state for clock (CKx) is a high level 0 = Idle state for clock (CKx) is a low level bit 3 BRG16: 16-Bit Baud Rate Register Enable bit 1 = 16-bit Baud Rate Generator – SPBRGHx and SPBRGx 0 = 8-bit Baud Rate Generator – SPBRGx only (Compatible mode), SPBRGHx value is ignored bit 2 Unimplemented: Read as ‘0’ bit 1 WUE: Wake-up Enable bit Asynchronous mode: 1 = EUSART will continue to sample the RXx pin – interrupt generated on the falling edge; bit cleared in hardware on the following rising edge 0 = RXx pin is not monitored or the rising edge detected Synchronous mode: Unused in this mode. bit 0 ABDEN: Auto-Baud Detect Enable bit Asynchronous mode: 1 = Enable baud rate measurement on the next character. Requires reception of a Sync field (55h); cleared in hardware upon completion. 0 = Baud rate measurement is disabled or completed Synchronous mode: Unused in this mode. DS39957B-page 350 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 22.1 Baud Rate Generator (BRG) The BRG is a dedicated, 8-bit or 16-bit generator that supports both the Asynchronous and Synchronous modes of the EUSART. By default, the BRG operates in 8-bit mode; setting the BRG16 bit (BAUDCONx<3>) selects 16-bit mode. The SPBRGHx:SPBRGx register pair controls the period of a free-running timer. In Asynchronous mode, bits, BRGH (TXSTAx<2>) and BRG16 (BAUDCONx<3>), also control the baud rate. In Synchronous mode, BRGH is ignored. Table 22-1 shows the formula for computation of the baud rate for different EUSART modes which only apply in Master mode (internally generated clock). Given the desired baud rate and FOSC, the nearest integer value for the SPBRGHx:SPBRGx registers can be calculated using the formulas in Table 22-1. From this, the error in baud rate can be determined. An example calculation is shown in Example 22-1. Typical baud rates and error values for the various Asynchronous modes are shown in Table 22-2. It may be advantageous to use the high baud rate (BRGH = 1) or the 16-bit BRG to reduce the baud rate error, or achieve a slow baud rate for a fast oscillator frequency. TABLE 22-1: Writing a new value to the SPBRGHx:SPBRGx registers causes the BRG timer to be reset (or cleared). This ensures the BRG does not wait for a timer overflow before outputting the new baud rate. When operated in Synchronous mode, SPBRGH:SPBRG values of 0000h and 0001h are not supported. In the Asynchronous mode, all BRG values may be used. 22.1.1 OPERATION IN POWER-MANAGED MODES The device clock is used to generate the desired baud rate. When one of the power-managed modes is entered, the new clock source may be operating at a different frequency. This may require an adjustment to the value in the SPBRGx register pair. 22.1.2 SAMPLING The data on the RXx pin (either RC7/RX1/DT1/SEG28 or RG2/RX2/DT2/AN18/C3INA) is sampled three times by a majority detect circuit to determine if a high or a low level is present at the RXx pin. BAUD RATE FORMULAS Configuration Bits BRG/EUSART Mode Baud Rate Formula 0 8-Bit/Asynchronous FOSC/[64 (n + 1)] 1 8-Bit/Asynchronous 1 0 16-Bit/Asynchronous 0 1 1 16-Bit/Asynchronous 1 0 x 8-Bit/Synchronous 1 1 x 16-Bit/Synchronous SYNC BRG16 BRGH 0 0 0 0 0 FOSC/[16 (n + 1)] FOSC/[4 (n + 1)] Legend: x = Don’t care, n = value of SPBRGHx:SPBRGx register pair 2010 Microchip Technology Inc. Preliminary DS39957B-page 351 PIC18F87K90 FAMILY EXAMPLE 22-1: CALCULATING BAUD RATE ERROR For a device with FOSC of 16 MHz, desired baud rate of 9600, Asynchronous mode, and 8-bit BRG: Desired Baud Rate = FOSC/(64 ([SPBRGHx:SPBRGx] + 1)) Solving for SPBRGHx:SPBRGx: X = ((FOSC/Desired Baud Rate)/64) – 1 = ((16000000/9600)/64) – 1 = [25.042] = 25 Calculated Baud Rate = 16000000/(64 (25 + 1)) = 9615 Error = (Calculated Baud Rate – Desired Baud Rate)/Desired Baud Rate = (9615 – 9600)/9600 = 0.16% TABLE 22-2: Name REGISTERS ASSOCIATED WITH BAUD RATE GENERATOR Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Reset Values on Page: TXSTA1 CSRC TX9 TXEN SYNC SENDB BRGH TRMT TX9D 75 RCSTA1 SPEN RX9 SREN CREN ADDEN FERR OERR RX9D 75 BAUDCON1 ABDOVF RCIDL RXDTP TXCKP BRG16 — WUE ABDEN 77 SPBRGH1 EUSART1 Baud Rate Generator Register High Byte SPBRG1 EUSART1 Baud Rate Generator Register Low Byte TXSTA2 RCSTA2 CSRC TX9 TXEN 74 75 SYNC SENDB BRGH TRMT TX9D 79 SPEN RX9 SREN CREN ADDEN FERR OERR RX9D 79 BAUDCON2 ABDOVF RCIDL RXDTP TXCKP BRG16 — WUE ABDEN 79 SPBRGH2 EUSART2 Baud Rate Generator Register High Byte 80 SPBRG2 EUSART2 Baud Rate Generator Register Low Byte 80 Legend: — = unimplemented, read as ‘0’. Shaded cells are not used by the BRG. DS39957B-page 352 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY TABLE 22-3: BAUD RATES FOR ASYNCHRONOUS MODES SYNC = 0, BRGH = 0, BRG16 = 0 BAUD RATE (K) FOSC = 40.000 MHz FOSC = 20.000 MHz FOSC = 10.000 MHz (decimal) % Error — — — — — 1.221 2.441 1.73 255 9.615 0.16 64 19.531 1.73 31 57.6 56.818 -1.36 10 62.500 8.51 4 52.083 -9.58 2 — — — 115.2 125.000 8.51 4 104.167 -9.58 2 78.125 -32.18 1 — — — % Error 0.3 1.2 — — 2.4 9.6 19.2 SPBRG value (decimal) Actual Rate (K) % Error — 1.73 — 255 — 1.202 2.404 0.16 129 9.766 1.73 31 19.531 1.73 15 FOSC = 8.000 MHz Actual Rate (K) Actual Rate (K) SPBRG value (decimal) Actual Rate (K) % Error — 0.16 — 129 — 1.201 — -0.16 — 103 2.404 0.16 64 2.403 -0.16 51 9.766 1.73 15 9.615 -0.16 12 19.531 1.73 7 — — — SPBRG value SPBRG value (decimal) SYNC = 0, BRGH = 0, BRG16 = 0 BAUD RATE (K) FOSC = 4.000 MHz FOSC = 2.000 MHz FOSC = 1.000 MHz (decimal) Actual Rate (K) 0.16 207 0.300 -0.16 103 0.300 -0.16 51 0.16 51 1.201 -0.16 25 1.201 -0.16 12 2.404 0.16 25 2.403 -0.16 12 — — — 9.6 8.929 -6.99 6 — — — — — — 19.2 20.833 8.51 2 — — — — — — Actual Rate (K) % Error 0.3 0.300 1.2 1.202 2.4 SPBRG value % Error (decimal) Actual Rate (K) % Error SPBRG value SPBRG value (decimal) 57.6 62.500 8.51 0 — — — — — — 115.2 62.500 -45.75 0 — — — — — — SYNC = 0, BRGH = 1, BRG16 = 0 BAUD RATE (K) FOSC = 40.000 MHz FOSC = 20.000 MHz (decimal) Actual Rate (K) % Error — — — — — — — — — 9.766 1.73 255 Actual Rate (K) % Error 0.3 — 1.2 — 2.4 9.6 SPBRG value FOSC = 10.000 MHz (decimal) Actual Rate (K) % Error — — — — — — — — — 9.615 0.16 FOSC = 8.000 MHz (decimal) Actual Rate (K) % Error — — — — — — — — — 2.441 1.73 255 2.403 -0.16 207 129 9.615 0.16 64 9.615 -0.16 51 25 SPBRG value SPBRG value SPBRG value (decimal) — 19.2 19.231 0.16 129 19.231 0.16 64 19.531 1.73 31 19.230 -0.16 57.6 58.140 0.94 42 56.818 -1.36 21 56.818 -1.36 10 55.555 3.55 8 115.2 113.636 -1.36 21 113.636 -1.36 10 125.000 8.51 4 — — — SYNC = 0, BRGH = 1, BRG16 = 0 BAUD RATE (K) FOSC = 4.000 MHz Actual Rate (K) % Error FOSC = 2.000 MHz SPBRG value (decimal) Actual Rate (K) % Error SPBRG value (decimal) FOSC = 1.000 MHz Actual Rate (K) % Error SPBRG value (decimal) 0.3 — — — — — — 0.300 -0.16 207 1.2 1.202 0.16 207 1.201 -0.16 103 1.201 -0.16 51 2.4 2.404 0.16 103 2.403 -0.16 51 2.403 -0.16 25 9.6 9.615 0.16 25 9.615 -0.16 12 — — — 19.2 19.231 0.16 12 — — — — — — 57.6 62.500 8.51 3 — — — — — — 115.2 125.000 8.51 1 — — — — — — 2010 Microchip Technology Inc. Preliminary DS39957B-page 353 PIC18F87K90 FAMILY TABLE 22-3: BAUD RATES FOR ASYNCHRONOUS MODES (CONTINUED) SYNC = 0, BRGH = 0, BRG16 = 1 BAUD RATE (K) FOSC = 40.000 MHz Actual Rate (K) % Error FOSC = 20.000 MHz SPBRG value (decimal) Actual Rate (K) % Error FOSC = 10.000 MHz (decimal) Actual Rate (K) SPBRG value % Error FOSC = 8.000 MHz (decimal) Actual Rate (K) % Error SPBRG value SPBRG value (decimal) 0.3 0.300 0.00 8332 0.300 0.02 4165 0.300 0.02 2082 0.300 -0.04 1.2 1.200 0.02 2082 1.200 -0.03 1041 1.200 -0.03 520 1.201 -0.16 1665 415 2.4 2.402 0.06 1040 2.399 -0.03 520 2.404 0.16 259 2.403 -0.16 207 9.6 9.615 0.16 259 9.615 0.16 129 9.615 0.16 64 9.615 -0.16 51 25 19.2 19.231 0.16 129 19.231 0.16 64 19.531 1.73 31 19.230 -0.16 57.6 58.140 0.94 42 56.818 -1.36 21 56.818 -1.36 10 55.555 3.55 8 115.2 113.636 -1.36 21 113.636 -1.36 10 125.000 8.51 4 — — — SYNC = 0, BRGH = 0, BRG16 = 1 BAUD RATE (K) FOSC = 4.000 MHz FOSC = 2.000 MHz (decimal) Actual Rate (K) % Error 0.04 832 0.300 0.16 207 1.201 2.404 0.16 103 9.6 9.615 0.16 19.2 19.231 57.6 62.500 115.2 125.000 FOSC = 1.000 MHz (decimal) Actual Rate (K) % Error -0.16 415 0.300 -0.16 -0.16 103 1.201 -0.16 51 2.403 -0.16 51 2.403 -0.16 25 25 9.615 -0.16 12 — — — 0.16 12 — — — — — — 8.51 3 — — — — — — 8.51 1 — — — — — — Actual Rate (K) % Error 0.3 0.300 1.2 1.202 2.4 SPBRG value SPBRG value SPBRG value (decimal) 207 SYNC = 0, BRGH = 1, BRG16 = 1 or SYNC = 1, BRG16 = 1 BAUD RATE (K) FOSC = 40.000 MHz FOSC = 20.000 MHz (decimal) Actual Rate (K) % Error 0.00 33332 0.300 0.00 8332 1.200 0.02 4165 Actual Rate (K) % Error 0.3 0.300 1.2 1.200 2.4 2.400 SPBRG value FOSC = 10.000 MHz (decimal) Actual Rate (K) % Error 0.00 16665 0.300 0.02 4165 1.200 2.400 0.02 2082 2.402 SPBRG value FOSC = 8.000 MHz (decimal) Actual Rate (K) % Error 0.00 8332 0.300 -0.01 6665 0.02 2082 1.200 -0.04 1665 0.06 1040 2.400 -0.04 832 SPBRG value SPBRG value (decimal) 9.6 9.606 0.06 1040 9.596 -0.03 520 9.615 0.16 259 9.615 -0.16 207 19.2 19.193 -0.03 520 19.231 0.16 259 19.231 0.16 129 19.230 -0.16 103 57.6 57.803 0.35 172 57.471 -0.22 86 58.140 0.94 42 57.142 0.79 34 115.2 114.943 -0.22 86 116.279 0.94 42 113.636 -1.36 21 117.647 -2.12 16 SYNC = 0, BRGH = 1, BRG16 = 1 or SYNC = 1, BRG16 = 1 BAUD RATE (K) 0.3 1.2 FOSC = 4.000 MHz Actual Rate (K) % Error 0.300 1.200 0.01 0.04 FOSC = 2.000 MHz (decimal) Actual Rate (K) % Error 3332 832 0.300 1.201 -0.04 -0.16 SPBRG value FOSC = 1.000 MHz (decimal) Actual Rate (K) % Error 1665 415 0.300 1.201 -0.04 -0.16 832 207 SPBRG value SPBRG value (decimal) 2.4 2.404 0.16 415 2.403 -0.16 207 2.403 -0.16 103 9.6 9.615 0.16 103 9.615 -0.16 51 9.615 -0.16 25 19.2 19.231 0.16 51 19.230 -0.16 25 19.230 -0.16 12 57.6 58.824 2.12 16 55.555 3.55 8 — — — 115.2 111.111 -3.55 8 — — — — — — DS39957B-page 354 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 22.1.3 AUTO-BAUD RATE DETECT The Enhanced USART module supports the automatic detection and calibration of baud rate. This feature is active only in Asynchronous mode and while the WUE bit is clear. The automatic baud rate measurement sequence (Figure 22-1) begins whenever a Start bit is received and the ABDEN bit is set. The calculation is self-averaging. While the ABD sequence takes place, the EUSART state machine is held in Idle. The RCxIF interrupt is set once the fifth rising edge on RXx is detected. The value in the RCREGx needs to be read to clear the RCxIF interrupt. The contents of RCREGx should be discarded. Note 1: If the WUE bit is set with the ABDEN bit, Auto-Baud Rate Detection will occur on the byte following the Break character. 2: It is up to the user to determine that the incoming character baud rate is within the range of the selected BRG clock source. Some combinations of oscillator frequency and EUSART baud rates are not possible due to bit error rates. Overall system timing and communication baud rates must be taken into consideration when using the Auto-Baud Rate Detection feature. In the Auto-Baud Rate Detect (ABD) mode, the clock to the BRG is reversed. Rather than the BRG clocking the incoming RXx signal, the RXx signal is timing the BRG. In ABD mode, the internal Baud Rate Generator is used as a counter to time the bit period of the incoming serial byte stream. Once the ABDEN bit is set, the state machine will clear the BRG and look for a Start bit. The Auto-Baud Rate Detect must receive a byte with the value, 55h (ASCII “U”, which is also the LIN/J2602 bus Sync character), in order to calculate the proper bit rate. The measurement is taken over both a low and a high bit time in order to minimize any effects caused by asymmetry of the incoming signal. After a Start bit, the SPBRGx begins counting up, using the preselected clock source on the first rising edge of RXx. After eight bits on the RXx pin or the fifth rising edge, an accumulated value totalling the proper BRG period is left in the SPBRGHx:SPBRGx register pair. Once the 5th edge is seen (this should correspond to the Stop bit), the ABDEN bit is automatically cleared. If a rollover of the BRG occurs (an overflow from FFFFh to 0000h), the event is trapped by the ABDOVF status bit (BAUDCONx<7>). It is set in hardware by BRG rollovers and can be set or cleared by the user in software. ABD mode remains active after rollover events and the ABDEN bit remains set (Figure 22-2). While calibrating the baud rate period, the BRG registers are clocked at 1/8th the preconfigured clock rate. Note that the BRG clock can be configured by the BRG16 and BRGH bits. The BRG16 bit must be set to use both SPBRG1 and SPBRGH1 as a 16-bit counter. This allows the user to verify that no carry occurred for 8-bit modes by checking for 00h in the SPBRGHx register. Refer to Table 22-4 for counter clock rates to the BRG. 2010 Microchip Technology Inc. 3: To maximize baud rate range, it is recommended to set the BRG16 (BAUDCONx<3>) bit if the auto-baud feature is used. TABLE 22-4: BRG COUNTER CLOCK RATES BRG16 BRGH BRG Counter Clock 0 0 FOSC/512 0 1 FOSC/128 1 0 FOSC/128 1 1 FOSC/32 22.1.3.1 ABD and EUSART Transmission Since the BRG clock is reversed during ABD acquisition, the EUSART transmitter cannot be used during ABD. This means that whenever the ABDEN bit is set, TXREGx cannot be written to. Users should also ensure that ABDEN does not become set during a transmit sequence. Failing to do this may result in unpredictable EUSART operation. Preliminary DS39957B-page 355 PIC18F87K90 FAMILY FIGURE 22-1: BRG Value AUTOMATIC BAUD RATE CALCULATION XXXXh RXx Pin 0000h 001Ch Start Edge #1 Bit 1 Bit 0 Edge #2 Bit 3 Bit 2 Edge #3 Bit 5 Bit 4 Edge #4 Bit 7 Bit 6 Edge #5 Stop Bit BRG Clock Auto-Cleared Set by User ABDEN bit RCxIF bit (Interrupt) Read RCREGx SPBRGx XXXXh 1Ch SPBRGHx XXXXh 00h Note: The ABD sequence requires the EUSART module to be configured in Asynchronous mode and WUE = 0. FIGURE 22-2: BRG OVERFLOW SEQUENCE BRG Clock ABDEN bit RXx Pin Start Bit 0 ABDOVF bit FFFFh BRG Value DS39957B-page 356 XXXXh 0000h 0000h Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 22.2 EUSART Asynchronous Mode Once the TXREGx register transfers the data to the TSR register (occurs in one TCY), the TXREGx register is empty and the TXxIF flag bit is set. This interrupt can be enabled or disabled by setting or clearing the interrupt enable bit, TXxIE. TXxIF will be set regardless of the state of TXxIE; it cannot be cleared in software. TXxIF is also not cleared immediately upon loading TXREGx, but becomes valid in the second instruction cycle following the load instruction. Polling TXxIF immediately following a load of TXREGx will return invalid results. The Asynchronous mode of operation is selected by clearing the SYNC bit (TXSTAx<4>). In this mode, the EUSART uses standard Non-Return-to-Zero (NRZ) format (one Start bit, eight or nine data bits and one Stop bit). The most common data format is 8 bits. An on-chip, dedicated 8-bit/16-bit Baud Rate Generator can be used to derive standard baud rate frequencies from the oscillator. The EUSART transmits and receives the LSb first. The EUSART’s transmitter and receiver are functionally independent but use the same data format and baud rate. The Baud Rate Generator produces a clock, either x16 or x64 of the bit shift rate, depending on the BRGH and BRG16 bits (TXSTAx<2> and BAUDCONx<3>). Parity is not supported by the hardware but can be implemented in software and stored as the 9th data bit. While TXxIF indicates the status of the TXREGx register; another bit, TRMT (TXSTAx<1>), shows the status of the TSR register. TRMT is a read-only bit which is set when the TSR register is empty. No interrupt logic is tied to this bit so the user has to poll this bit in order to determine if the TSR register is empty. Note 1: The TSR register is not mapped in data memory, so it is not available to the user. When operating in Asynchronous mode, the EUSART module consists of the following important elements: • • • • • • • 2: Flag bit, TXxIF, is set when enable bit, TXEN, is set. Baud Rate Generator Sampling Circuit Asynchronous Transmitter Asynchronous Receiver Auto-Wake-up on Sync Break Character 12-Bit Break Character Transmit Auto-Baud Rate Detection 22.2.1 To set up an Asynchronous Transmission: 1. 2. EUSART ASYNCHRONOUS TRANSMITTER 3. 4. The EUSART transmitter block diagram is shown in Figure 22-3. The heart of the transmitter is the Transmit (Serial) Shift Register (TSR). The Shift register obtains its data from the Read/Write Transmit Buffer register, TXREGx. The TXREGx register is loaded with data in software. The TSR register is not loaded until the Stop bit has been transmitted from the previous load. As soon as the Stop bit is transmitted, the TSR is loaded with new data from the TXREGx register (if available). FIGURE 22-3: 5. 6. 7. 8. Initialize the SPBRGHx:SPBRGx registers for the appropriate baud rate. Set or clear the BRGH and BRG16 bits, as required, to achieve the desired baud rate. Enable the asynchronous serial port by clearing bit, SYNC, and setting bit, SPEN. If interrupts are desired, set enable bit, TXxIE. If 9-bit transmission is desired, set transmit bit, TX9. Can be used as address/data bit. Enable the transmission by setting bit, TXEN, which will also set bit, TXxIF. If 9-bit transmission is selected, the ninth bit should be loaded in bit, TX9D. Load data to the TXREGx register (starts transmission). If using interrupts, ensure that the GIE and PEIE bits in the INTCON register (INTCON<7:6>) are set. EUSART TRANSMIT BLOCK DIAGRAM Data Bus TXxIF TXREGx Register TXxIE 8 MSb (8) LSb Pin Buffer and Control 0 TSR Register TXx Pin Interrupt TXEN Baud Rate CLK TRMT BRG16 SPBRGHx SPBRGx Baud Rate Generator 2010 Microchip Technology Inc. SPEN TX9 TX9D Preliminary DS39957B-page 357 PIC18F87K90 FAMILY FIGURE 22-4: Write to TXREGx BRG Output (Shift Clock) ASYNCHRONOUS TRANSMISSION Word 1 TXx (pin) Start bit FIGURE 22-5: bit 1 bit 7/8 Stop bit Word 1 TXxIF bit (Transmit Buffer Reg. Empty Flag) TRMT bit (Transmit Shift Reg. Empty Flag) bit 0 1 TCY Word 1 Transmit Shift Reg ASYNCHRONOUS TRANSMISSION (BACK-TO-BACK) Write to TXREGx Word 1 Word 2 BRG Output (Shift Clock) TXx (pin) TXxIF bit (Interrupt Reg. Flag) TRMT bit (Transmit Shift Reg. Empty Flag) Start bit bit 0 1 TCY bit 1 Word 1 bit 7/8 Stop bit Start bit bit 0 Word 2 1 TCY Word 1 Transmit Shift Reg. Word 2 Transmit Shift Reg. Note: This timing diagram shows two consecutive transmissions. DS39957B-page 358 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY TABLE 22-5: Name INTCON REGISTERS ASSOCIATED WITH ASYNCHRONOUS TRANSMISSION Bit 7 Bit 6 GIE/GIEH PEIE/GIEL Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Reset Values on Page: TMR0IE INT0IE RBIE TMR0IF INT0IF RBIF 73 PIR1 — ADIF RC1IF TX1IF SSP1IF TMR1GIF TMR2IF TMR1IF 75 PIE1 — ADIE RC1IE TX1IE SSP1IE TMR1GIE TMR2IE TMR1IE 75 IPR1 — ADIP RC1IP TX1IP SSP1IP TMR1GIP TMR2IP TMR1IP 75 PIR3 TMR5GIF LCDIF RC2IF TX2IF CTMUIF CCP2IF CCP1IF RTCCIF 75 PIE3 TMR5GIE LCDIE RC2IE TX2IE CTMUIE CCP2IE CCP1IE RTCCIE 75 IPR3 TMR5GIP LCDIP RC2IP TX2IP CTMUIP CCP2IP CCP1IP RTCCIP 75 SPEN RX9 SREN CREN ADDEN FERR OERR RX9D 75 RCSTA1 TXREG1 TXSTA1 EUSART1 Transmit Register 75 CSRC TX9 TXEN SYNC SENDB BRGH TRMT TX9D 75 BAUDCON1 ABDOVF RCIDL RXDTP TXCKP BRG16 — WUE ABDEN 77 SPBRGH1 EUSART1 Baud Rate Generator Register High Byte SPBRG1 EUSART1 Baud Rate Generator Register Low Byte RCSTA2 TXREG2 TXSTA2 SPEN RX9 SREN CREN ADDEN 74 75 FERR OERR RX9D EUSART2 Transmit Register 79 80 CSRC TX9 TXEN SYNC SENDB BRGH TRMT TX9D 79 BAUDCON2 ABDOVF RCIDL RXDTP TXCKP BRG16 — WUE ABDEN 79 SPBRGH2 EUSART2 Baud Rate Generator Register High Byte 80 SPBRG2 EUSART2 Baud Rate Generator Register Low Byte 80 Legend: — = unimplemented locations read as ‘0’. Shaded cells are not used for asynchronous transmission. 2010 Microchip Technology Inc. Preliminary DS39957B-page 359 PIC18F87K90 FAMILY 22.2.2 EUSART ASYNCHRONOUS RECEIVER 22.2.3 The receiver block diagram is shown in Figure 22-6. The data is received on the RXx pin and drives the data recovery block. The data recovery block is actually a high-speed shifter operating at x16 times the baud rate, whereas the main receive serial shifter operates at the bit rate or at FOSC. This mode would typically be used in RS-232 systems. This mode would typically be used in RS-485 systems. To set up an Asynchronous Reception with Address Detect Enable: 1. Initialize the SPBRGHx:SPBRGx registers for the appropriate baud rate. Set or clear the BRGH and BRG16 bits, as required, to achieve the desired baud rate. 2. Enable the asynchronous serial port by clearing the SYNC bit and setting the SPEN bit. 3. If interrupts are required, set the RCEN bit and select the desired priority level with the RCxIP bit. 4. Set the RX9 bit to enable 9-bit reception. 5. Set the ADDEN bit to enable address detect. 6. Enable reception by setting the CREN bit. 7. The RCxIF bit will be set when reception is complete. The interrupt will be Acknowledged if the RCxIE and GIE bits are set. 8. Read the RCSTAx register to determine if any error occurred during reception, as well as read bit 9 of data (if applicable). 9. Read RCREGx to determine if the device is being addressed. 10. If any error occurred, clear the CREN bit. 11. If the device has been addressed, clear the ADDEN bit to allow all received data into the receive buffer and interrupt the CPU. To set up an Asynchronous Reception: 1. Initialize the SPBRGHx:SPBRGx registers for the appropriate baud rate. Set or clear the BRGH and BRG16 bits, as required, to achieve the desired baud rate. 2. Enable the asynchronous serial port by clearing bit, SYNC, and setting bit, SPEN. 3. If interrupts are desired, set enable bit, RCxIE. 4. If 9-bit reception is desired, set bit, RX9. 5. Enable the reception by setting bit, CREN. 6. Flag bit, RCxIF, will be set when reception is complete and an interrupt will be generated if enable bit, RCxIE, was set. 7. Read the RCSTAx register to get the 9th bit (if enabled) and determine if any error occurred during reception. 8. Read the 8-bit received data by reading the RCREGx register. 9. If any error occurred, clear the error by clearing enable bit, CREN. 10. If using interrupts, ensure that the GIE and PEIE bits in the INTCON register (INTCON<7:6>) are set. FIGURE 22-6: SETTING UP 9-BIT MODE WITH ADDRESS DETECT EUSART RECEIVE BLOCK DIAGRAM CREN OERR FERR x64 Baud Rate CLK BRG16 SPBRGHx SPBRGx Baud Rate Generator 64 or 16 or 4 RSR Register MSb Stop (8) 7 LSb 1 0 Start RX9 Pin Buffer and Control Data Recovery RXx RX9D RCREGx Register FIFO SPEN 8 Interrupt RCxIF Data Bus RCxIE DS39957B-page 360 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY FIGURE 22-7: ASYNCHRONOUS RECEPTION Start bit RXx (pin) bit 0 bit 7/8 Stop bit bit 1 Rcv Shift Reg Rcv Buffer Reg Start bit bit 0 Stop bit Start bit bit 7/8 Stop bit Word 2 RCREGx Word 1 RCREGx Read Rcv Buffer Reg RCREGx bit 7/8 RCxIF (Interrupt Flag) OERR bit CREN Note: This timing diagram shows three words appearing on the RXx input. The RCREGx (Receive Buffer) is read after the third word causing the OERR (Overrun) bit to be set. TABLE 22-6: Name INTCON REGISTERS ASSOCIATED WITH ASYNCHRONOUS RECEPTION Bit 7 Bit 6 GIE/GIEH PEIE/GIEL Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Reset Values on Page: TMR0IE INT0IE RBIE TMR0IF INT0IF RBIF 73 PIR1 — ADIF RC1IF TX1IF SSP1IF TMR1GIF TMR2IF TMR1IF 75 PIE1 — ADIE RC1IE TX1IE SSP1IE TMR1GIE TMR2IE TMR1IE 75 IPR1 — ADIP RC1IP TX1IP SSP1IP TMR1GIP TMR2IP TMR1IP 75 PIR3 TMR5GIF LCDIF RC2IF TX2IF CTMUIF CCP2IF CCP1IF RTCCIF 75 PIE3 TMR5GIE LCDIE RC2IE TX2IE CTMUIE CCP2IE CCP1IE RTCCIE 75 IPR3 TMR5GIP LCDIP RC2IP TX2IP CTMUIP CCP2IP CCP1IP RTCCIP 75 SPEN RX9 SREN CREN ADDEN FERR OERR RX9D 75 RCSTA1 RCREG1 TXSTA1 BAUDCON1 EUSART1 Receive Register 75 CSRC TX9 TXEN SYNC SENDB BRGH TRMT TX9D 75 ABDOVF RCIDL RXDTP TXCKP BRG16 — WUE ABDEN 77 SPBRGH1 EUSART1 Baud Rate Generator Register High Byte 74 SPBRG1 EUSART1 Baud Rate Generator Register Low Byte 75 RCSTA2 RCREG2 TXSTA2 BAUDCON2 SPEN RX9 SREN CREN ADDEN FERR OERR RX9D EUSART2 Receive Register 79 80 CSRC TX9 TXEN SYNC SENDB BRGH TRMT TX9D 79 ABDOVF RCIDL RXDTP TXCKP BRG16 — WUE ABDEN 79 SPBRGH2 EUSART2 Baud Rate Generator Register High Byte 80 SPBRG2 EUSART2 Baud Rate Generator Register Low Byte 80 Legend: — = unimplemented locations read as ‘0’. Shaded cells are not used for asynchronous reception. 2010 Microchip Technology Inc. Preliminary DS39957B-page 361 PIC18F87K90 FAMILY 22.2.4 AUTO-WAKE-UP ON SYNC BREAK CHARACTER During Sleep mode, all clocks to the EUSART are suspended. Because of this, the Baud Rate Generator is inactive and a proper byte reception cannot be performed. The auto-wake-up feature allows the controller to wake-up due to activity on the RXx/DTx line while the EUSART is operating in Asynchronous mode. The auto-wake-up feature is enabled by setting the WUE bit (BAUDCONx<1>). Once set, the typical receive sequence on RXx/DTx is disabled and the EUSART remains in an Idle state, monitoring for a wake-up event independent of the CPU mode. A wake-up event consists of a high-to-low transition on the RXx/DTx line. (This coincides with the start of a Sync Break or a Wake-up Signal character for the LIN/J2602 protocol.) 22.2.4.1 Special Considerations Using Auto-Wake-up Since auto-wake-up functions by sensing rising edge transitions on RXx/DTx, information with any state changes before the Stop bit may signal a false End-of-Character (EOC) and cause data or framing errors. To work properly, therefore, the initial character in the transmission must be all ‘0’s. This can be 00h (8 bits) for standard RS-232 devices or 000h (12 bits) for LIN/J2602 bus. Oscillator start-up time must also be considered, especially in applications using oscillators with longer start-up intervals (i.e., HS or HSPLL mode). The Sync Break (or Wake-up Signal) character must be of sufficient length and be followed by a sufficient interval to allow enough time for the selected oscillator to start and provide proper initialization of the EUSART. Following a wake-up event, the module generates an RCxIF interrupt. The interrupt is generated synchronously to the Q clocks in normal operating modes (Figure 22-8) and asynchronously if the device is in Sleep mode (Figure 22-9). The interrupt condition is cleared by reading the RCREGx register. The WUE bit is automatically cleared once a low-to-high transition is observed on the RXx line following the wake-up event. At this point, the EUSART module is in Idle mode and returns to normal operation. This signals to the user that the Sync Break event is over. DS39957B-page 362 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 22.2.4.2 Special Considerations Using the WUE Bit The timing of WUE and RCxIF events may cause some confusion when it comes to determining the validity of received data. As noted, setting the WUE bit places the EUSART in an Idle mode. The wake-up event causes a receive interrupt by setting the RCxIF bit. The WUE bit is cleared after this when a rising edge is seen on RXx/DTx. The interrupt condition is then cleared by reading the RCREGx register. Ordinarily, the data in RCREGx will be dummy data and should be discarded. FIGURE 22-8: The fact that the WUE bit has been cleared (or is still set) and the RCxIF flag is set should not be used as an indicator of the integrity of the data in RCREGx. Users should consider implementing a parallel method in firmware to verify received data integrity. To assure that no actual data is lost, check the RCIDL bit to verify that a receive operation is not in process. If a receive operation is not occurring, the WUE bit may then be set just prior to entering the Sleep mode. AUTO-WAKE-UP BIT (WUE) TIMINGS DURING NORMAL OPERATION Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 OSC1 WUE bit(1) Bit Set by User Auto-Cleared RXx/DTx Line RCxIF Note 1: Cleared due to User Read of RCREGx The EUSART remains in Idle while the WUE bit is set. FIGURE 22-9: AUTO-WAKE-UP BIT (WUE) TIMINGS DURING SLEEP Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 OSC1 WUE bit(2) Auto-Cleared Bit Set by User RXx/DTx Line Note 1 RCxIF Sleep Ends SLEEP Command Executed Note 1: 2: Cleared due to User Read of RCREGx If the wake-up event requires long oscillator warm-up time, the auto-clear of the WUE bit can occur before the oscillator is ready. This sequence should not depend on the presence of Q clocks. The EUSART remains in Idle while the WUE bit is set. 2010 Microchip Technology Inc. Preliminary DS39957B-page 363 PIC18F87K90 FAMILY 22.2.5 BREAK CHARACTER SEQUENCE The EUSART module has the capability of sending the special Break character sequences that are required by the LIN/J2602 bus standard. The Break character transmit consists of a Start bit, followed by twelve ‘0’ bits and a Stop bit. The Frame Break character is sent whenever the SENDB and TXEN bits (TXSTAx<3> and TXSTAx<5>, respectively) are set while the Transmit Shift Register is loaded with data. Note that the value of data written to TXREGx will be ignored and all ‘0’s will be transmitted. The SENDB bit is automatically reset by hardware after the corresponding Stop bit is sent. This allows the user to preload the transmit FIFO with the next transmit byte following the Break character (typically, the Sync character in the LIN/J2602 specification). Note that the data value written to the TXREGx for the Break character is ignored. The write simply serves the purpose of initiating the proper sequence. The TRMT bit indicates when the transmit operation is active or Idle, just as it does during normal transmission. See Figure 22-10 for the timing of the Break character sequence. 22.2.5.1 Break and Sync Transmit Sequence The following sequence will send a message frame header made up of a Break, followed by an Auto-Baud Sync byte. This sequence is typical of a LIN/J2602 bus master. FIGURE 22-10: Write to TXREGx 1. 2. 3. 4. 5. Configure the EUSART for the desired mode. Set the TXEN and SENDB bits to set up the Break character. Load the TXREGx with a dummy character to initiate transmission (the value is ignored). Write ‘55h’ to TXREGx to load the Sync character into the transmit FIFO buffer. After the Break has been sent, the SENDB bit is reset by hardware. The Sync character now transmits in the preconfigured mode. When the TXREGx becomes empty, as indicated by the TXxIF, the next data byte can be written to TXREGx. 22.2.6 RECEIVING A BREAK CHARACTER The Enhanced USART module can receive a Break character in two ways. The first method forces configuration of the baud rate at a frequency of 9/13 the typical speed. This allows for the Stop bit transition to be at the correct sampling location (13 bits for Break versus Start bit and 8 data bits for typical data). The second method uses the auto-wake-up feature described in Section 22.2.4 “Auto-Wake-up on Sync Break Character”. By enabling this feature, the EUSART will sample the next two transitions on RXx/DTx, cause an RCxIF interrupt and receive the next data byte followed by another interrupt. Note that following a Break character, the user will typically want to enable the Auto-Baud Rate Detect feature. For both methods, the user can set the ABDEN bit once the TXxIF interrupt is observed. SEND BREAK CHARACTER SEQUENCE Dummy Write BRG Output (Shift Clock) TXx (pin) Start Bit Bit 0 Bit 1 Bit 11 Stop Bit Break TXxIF bit (Transmit Buffer Reg. Empty Flag) TRMT bit (Transmit Shift Reg. Empty Flag) SENDB Sampled Here Auto-Cleared SENDB bit (Transmit Shift Reg. Empty Flag) DS39957B-page 364 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 22.3 EUSART Synchronous Master Mode Once the TXREGx register transfers the data to the TSR register (occurs in one TCY), the TXREGx is empty and the TXxIF flag bit is set. The interrupt can be enabled or disabled by setting or clearing the interrupt enable bit, TXxIE. TXxIF is set regardless of the state of enable bit, TXxIE; it cannot be cleared in software. It will reset only when new data is loaded into the TXREGx register. The Synchronous Master mode is entered by setting the CSRC bit (TXSTAx<7>). In this mode, the data is transmitted in a half-duplex manner (i.e., transmission and reception do not occur at the same time). When transmitting data, the reception is inhibited and vice versa. Synchronous mode is entered by setting bit, SYNC (TXSTAx<4>). In addition, enable bit, SPEN (RCSTAx<7>), is set in order to configure the TXx and RXx pins to CKx (clock) and DTx (data) lines, respectively. While flag bit, TXxIF, indicates the status of the TXREGx register, another bit, TRMT (TXSTAx<1>), shows the status of the TSR register. TRMT is a read-only bit which is set when the TSR is empty. No interrupt logic is tied to this bit, so the user must poll this bit in order to determine if the TSR register is empty. The TSR is not mapped in data memory so it is not available to the user. The Master mode indicates that the processor transmits the master clock on the CKx line. Clock polarity is selected with the TXCKP bit (BAUDCONx<4>). Setting TXCKP sets the Idle state on CKx as high, while clearing the bit sets the Idle state as low. This option is provided to support Microwire devices with this module. 22.3.1 To set up a Synchronous Master Transmission: 1. EUSART SYNCHRONOUS MASTER TRANSMISSION 2. 3. 4. 5. 6. The EUSART transmitter block diagram is shown in Figure 22-3. The heart of the transmitter is the Transmit (Serial) Shift Register (TSR). The TSR register obtains its data from the Read/Write Transmit Buffer register, TXREGx. The TXREGx register is loaded with data in software. The TSR register is not loaded until the last bit has been transmitted from the previous load. As soon as the last bit is transmitted, the TSR is loaded with new data from the TXREGx (if available). FIGURE 22-11: 7. 8. Initialize the SPBRGHx:SPBRGx registers for the appropriate baud rate. Set or clear the BRG16 bit, as required, to achieve the desired baud rate. Enable the synchronous master serial port by setting bits, SYNC, SPEN and CSRC. If interrupts are desired, set enable bit, TXxIE. If 9-bit transmission is desired, set bit, TX9. Enable the transmission by setting bit, TXEN. If 9-bit transmission is selected, the ninth bit should be loaded in bit, TX9D. Start transmission by loading data to the TXREGx register. If using interrupts, ensure that the GIE and PEIE bits in the INTCON register (INTCON<7:6>) are set. SYNCHRONOUS TRANSMISSION Q1 Q2 Q3Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1Q2 Q3 Q4 Q1 Q2 Q3 Q4 RC7/RX1/DT1/ SEG28 Pin bit 0 bit 1 bit 2 Q3 Q4 Q1 Q2 Q3 Q4 Q1Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 bit 7 bit 0 bit 1 bit 7 Word 2 Word 1 RC6/TX1/CK1/ SEG27 Pin (TXCKP = 0) RC6/TX1/CK1/ SEG27 Pin (TXCKP = 1) Write to TXREG1 Reg Write Word 1 Write Word 2 TX1IF bit (Interrupt Flag) TRMT bit TXEN bit Note: ‘1’ ‘1’ Sync Master mode, SPBRGx = 0, continuous transmission of two 8-bit words. This example is equally applicable to EUSART2 (RG1/TX2/CK2/AN19/C3OUT and RG2/RX2/DT2/AN18/C3INA). 2010 Microchip Technology Inc. Preliminary DS39957B-page 365 PIC18F87K90 FAMILY FIGURE 22-12: SYNCHRONOUS TRANSMISSION (THROUGH TXEN) RC7/RX1/DT1/SEG28 Pin bit 0 bit 1 bit 2 bit 6 bit 7 RC6/TX1/CK1/SEG27 Pin Write to TXREG1 reg TX1IF bit TRMT bit TXEN bit Note: This example is equally applicable to EUSART2 (RG1/TX2/CK2/AN19/C3OUT and RG2/RX2/DT2/AN18/C3INA). TABLE 22-7: Name INTCON REGISTERS ASSOCIATED WITH SYNCHRONOUS MASTER TRANSMISSION Bit 7 Bit 6 Bit 5 GIE/GIEH PEIE/GIEL TMR0IE Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Reset Values on Page: INT0IE RBIE TMR0IF INT0IF RBIF 73 PIR1 — ADIF RC1IF TX1IF SSP1IF TMR1GIF TMR2IF TMR1IF 75 PIE1 — ADIE RC1IE TX1IE SSP1IE TMR1GIE TMR2IE TMR1IE 75 IPR1 — ADIP RC1IP TX1IP SSP1IP TMR1GIP TMR2IP TMR1IP 75 PIR3 TMR5GIF LCDIF RC2IF TX2IF CTMUIF CCP2IF CCP1IF RTCCIF 75 PIE3 TMR5GIE LCDIE RC2IE TX2IE CTMUIE CCP2IE CCP1IE RTCCIE 75 IPR3 TMR5GIP LCDIP RC2IP TX2IP CTMUIP CCP2IP CCP1IP RTCCIP 75 SPEN RX9 SREN CREN ADDEN FERR OERR RX9D 75 RCSTA1 TXREG1 EUSART1 Transmit Register 75 CSRC TX9 TXEN SYNC SENDB BRGH TRMT TX9D 75 BAUDCON1 ABDOVF RCIDL RXDTP TXCKP BRG16 — WUE ABDEN 77 SPBRGH1 EUSART1 Baud Rate Generator Register High Byte SPBRG1 EUSART1 Baud Rate Generator Register Low Byte TXSTA1 RCSTA2 TXREG2 TXSTA2 SPEN RX9 SREN 74 75 CREN ADDEN FERR OERR RX9D EUSART2 Transmit Register 79 80 CSRC TX9 TXEN SYNC SENDB BRGH TRMT TX9D 79 BAUDCON2 ABDOVF RCIDL RXDTP TXCKP BRG16 — WUE ABDEN 79 SPBRGH2 EUSART2 Baud Rate Generator Register High Byte 80 SPBRG2 EUSART2 Baud Rate Generator Register Low Byte 80 Legend: — = unimplemented, read as ‘0’. Shaded cells are not used for synchronous master transmission. DS39957B-page 366 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 22.3.2 EUSART SYNCHRONOUS MASTER RECEPTION 3. 4. 5. 6. Ensure bits, CREN and SREN, are clear. If interrupts are desired, set enable bit, RCxIE. If 9-bit reception is desired, set bit, RX9. If a single reception is required, set bit, SREN. For continuous reception, set bit, CREN. 7. Interrupt flag bit, RCxIF, will be set when reception is complete and an interrupt will be generated if the enable bit, RCxIE, was set. 8. Read the RCSTAx register to get the 9th bit (if enabled) and determine if any error occurred during reception. 9. Read the 8-bit received data by reading the RCREGx register. 10. If any error occurred, clear the error by clearing bit CREN. 11. If using interrupts, ensure that the GIE and PEIE bits in the INTCON register (INTCON<7:6>) are set. Once Synchronous mode is selected, reception is enabled by setting either the Single Receive Enable bit, SREN (RCSTAx<5>) or the Continuous Receive Enable bit, CREN (RCSTAx<4>). Data is sampled on the RXx pin on the falling edge of the clock. If enable bit, SREN, is set, only a single word is received. If enable bit, CREN, is set, the reception is continuous until CREN is cleared. If both bits are set, then CREN takes precedence. To set up a Synchronous Master Reception: 1. 2. Initialize the SPBRGHx:SPBRGx registers for the appropriate baud rate. Set or clear the BRG16 bit, as required, to achieve the desired baud rate. Enable the synchronous master serial port by setting bits, SYNC, SPEN and CSRC. FIGURE 22-13: SYNCHRONOUS RECEPTION (MASTER MODE, SREN) Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 RC7/RX1/DT1/ SEG28 Pin bit 0 bit 1 bit 2 bit 3 bit 4 bit 5 bit 6 bit 7 RC6/TX1/CK1/ SEG27 Pin (TXCKP = 0) RC6/TX1/CK1/ SEG27 Pin (TXCKP = 1) Write to bit, SREN SREN bit CREN bit ‘0’ ‘0’ RC1IF bit (Interrupt) Read RCREG1 Note: Timing diagram demonstrates Sync Master mode with bit, SREN = 1, and bit, BRGH = 0. This example is equally applicable to EUSART2 (RG1/TX2/CK2/AN19/C3OUT and RG2/RX2/DT2/AN18/C3INA). 2010 Microchip Technology Inc. Preliminary DS39957B-page 367 PIC18F87K90 FAMILY TABLE 22-8: Name INTCON REGISTERS ASSOCIATED WITH SYNCHRONOUS MASTER RECEPTION Bit 7 Bit 6 Bit 5 GIE/GIEH PEIE/GIEL TMR0IE Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Reset Values on Page: INT0IE RBIE TMR0IF INT0IF RBIF 73 TMR1GIF PIR1 — ADIF RC1IF TX1IF SSP1IF TMR2IF TMR1IF 75 PIE1 — ADIE RC1IE TX1IE SSP1IE TMR1GIE TMR2IE TMR1IE 75 IPR1 — ADIP RC1IP TX1IP SSP1IP TMR1GIP TMR2IP TMR1IP 75 PIR3 TMR5GIF LCDIF RC2IF TX2IF CTMUIF CCP2IF CCP1IF RTCCIF 75 PIE3 TMR5GIE LCDIE RC2IE TX2IE CTMUIE CCP2IE CCP1IE RTCCIE 75 IPR3 TMR5GIP LCDIP RC2IP TX2IP CTMUIP CCP2IP CCP1IP RTCCIP 75 SPEN RX9 SREN CREN ADDEN FERR OERR RX9D RCSTA1 RCREG1 TXSTA1 EUSART1 Receive Register CSRC BAUDCON1 ABDOVF 75 75 TX9 TXEN SYNC SENDB BRGH TRMT TX9D 75 RCIDL RXDTP TXCKP BRG16 — WUE ABDEN 77 SPBRGH1 EUSART1 Baud Rate Generator Register High Byte 74 SPBRG1 EUSART1 Baud Rate Generator Register Low Byte 75 RCSTA2 RCREG2 TXSTA2 SPEN RX9 SREN CREN ADDEN FERR OERR RX9D EUSART2 Receive Register CSRC BAUDCON2 ABDOVF 79 80 TX9 TXEN SYNC SENDB BRGH TRMT TX9D 79 RCIDL RXDTP TXCKP BRG16 — WUE ABDEN 79 SPBRGH2 EUSART2 Baud Rate Generator Register High Byte 80 SPBRG2 EUSART2 Baud Rate Generator Register Low Byte 80 Legend: — = unimplemented, read as ‘0’. Shaded cells are not used for synchronous master reception. DS39957B-page 368 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 22.4 EUSART Synchronous Slave Mode e) Synchronous Slave mode is entered by clearing bit, CSRC (TXSTAx<7>). This mode differs from the Synchronous Master mode in that the shift clock is supplied externally at the CKx pin (instead of being supplied internally in Master mode). This allows the device to transfer or receive data while in any low-power mode. 22.4.1 EUSART SYNCHRONOUS SLAVE TRANSMISSION The operation of the Synchronous Master and Slave modes is identical, except in the case of Sleep mode. To set up a Synchronous Slave Transmission: 1. 2. 3. 4. 5. If two words are written to the TXREGx and then the SLEEP instruction is executed, the following will occur: 6. a) 7. b) c) d) The first word will immediately transfer to the TSR register and transmit. The second word will remain in the TXREGx register. Flag bit, TXxIF, will not be set. When the first word has been shifted out of TSR, the TXREGx register will transfer the second word to the TSR and flag bit, TXxIF, will now be set. TABLE 22-9: Name If enable bit, TXxIE, is set, the interrupt will wake the chip from Sleep. If the global interrupt is enabled, the program will branch to the interrupt vector. 8. Enable the synchronous slave serial port by setting bits, SYNC and SPEN, and clearing bit, CSRC. Clear bits, CREN and SREN. If interrupts are desired, set enable bit, TXxIE. If 9-bit transmission is desired, set bit, TX9. Enable the transmission by setting enable bit, TXEN. If 9-bit transmission is selected, the ninth bit should be loaded in bit, TX9D. Start transmission by loading data to the TXREGx register. If using interrupts, ensure that the GIE and PEIE bits in the INTCON register (INTCON<7:6>) are set. REGISTERS ASSOCIATED WITH SYNCHRONOUS SLAVE TRANSMISSION Bit 7 Bit 6 Bit 5 Bit 3 Bit 2 Bit 1 Bit 0 Reset Values on Page: INT0IE RBIE TMR0IF INT0IF RBIF 73 PIR1 — ADIF RC1IF TX1IF SSP1IF TMR1GIF TMR2IF TMR1IF 75 PIE1 — ADIE RC1IE TX1IE SSP1IE TMR1GIE TMR2IE TMR1IE 75 IPR1 — ADIP RC1IP TX1IP SSP1IP TMR1GIP TMR2IP TMR1IP 75 INTCON GIE/GIEH PEIE/GIEL TMR0IE Bit 4 PIR3 TMR5GIF LCDIF RC2IF TX2IF CTMUIF CCP2IF CCP1IF RTCCIF 75 PIE3 TMR5GIE LCDIE RC2IE TX2IE CTMUIE CCP2IE CCP1IE RTCCIE 75 IPR3 TMR5GIP LCDIP RC2IP TX2IP CTMUIP CCP2IP CCP1IP RTCCIP 75 SPEN RX9 SREN CREN ADDEN FERR OERR RX9D 75 RCSTA1 TXREG1 TXSTA1 EUSART1 Transmit Register 75 CSRC TX9 TXEN SYNC SENDB BRGH TRMT TX9D 75 RCIDL RXDTP TXCKP BRG16 — WUE ABDEN 77 BAUDCON1 ABDOVF SPBRGH1 EUSART1 Baud Rate Generator Register High Byte SPBRG1 EUSART1 Baud Rate Generator Register Low Byte RCSTA2 TXREG2 TXSTA2 SPEN RX9 SREN 74 75 CREN ADDEN FERR OERR RX9D EUSART2 Transmit Register 79 80 CSRC TX9 TXEN SYNC SENDB BRGH TRMT TX9D 79 RCIDL RXDTP TXCKP BRG16 — WUE ABDEN 79 BAUDCON2 ABDOVF SPBRGH2 EUSART2 Baud Rate Generator Register High Byte 80 SPBRG2 EUSART2 Baud Rate Generator Register Low Byte 80 Legend: — = unimplemented, read as ‘0’. Shaded cells are not used for synchronous slave transmission. 2010 Microchip Technology Inc. Preliminary DS39957B-page 369 PIC18F87K90 FAMILY 22.4.2 EUSART SYNCHRONOUS SLAVE RECEPTION To set up a Synchronous Slave Reception: 1. The operation of the Synchronous Master and Slave modes is identical, except in the case of Sleep, or any Idle mode and bit, SREN, which is a “don’t care” in Slave mode. If receive is enabled by setting the CREN bit prior to entering Sleep or any Idle mode, then a word may be received while in this low-power mode. Once the word is received, the RSR register will transfer the data to the RCREGx register. If the RCxIE enable bit is set, the interrupt generated will wake the chip from the low-power mode. If the global interrupt is enabled, the program will branch to the interrupt vector. 2. 3. 4. 5. 6. 7. 8. 9. Enable the synchronous master serial port by setting bits, SYNC and SPEN, and clearing bit, CSRC. If interrupts are desired, set enable bit, RCxIE. If 9-bit reception is desired, set bit, RX9. To enable reception, set enable bit, CREN. Flag bit, RCxIF, will be set when reception is complete. An interrupt will be generated if enable bit, RCxIE, was set. Read the RCSTAx register to get the 9th bit (if enabled) and determine if any error occurred during reception. Read the 8-bit received data by reading the RCREGx register. If any error occurred, clear the error by clearing bit, CREN. If using interrupts, ensure that the GIE and PEIE bits in the INTCON register (INTCON<7:6>) are set. TABLE 22-10: REGISTERS ASSOCIATED WITH SYNCHRONOUS SLAVE RECEPTION Name INTCON Bit 7 Bit 6 GIE/GIEH PEIE/GIEL Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Reset Values on Page: TMR0IE INT0IE RBIE TMR0IF INT0IF RBIF 73 PIR1 — ADIF RC1IF TX1IF SSP1IF TMR1GIF TMR2IF TMR1IF 75 PIE1 — ADIE RC1IE TX1IE SSP1IE TMR1GIE TMR2IE TMR1IE 75 IPR1 — ADIP RC1IP TX1IP SSP1IP TMR1GIP TMR2IP TMR1IP 75 PIR3 TMR5GIF LCDIF RC2IF TX2IF CTMUIF CCP2IF CCP1IF RTCCIF 75 PIE3 TMR5GIE LCDIE RC2IE TX2IE CTMUIE CCP2IE CCP1IE RTCCIE 75 IPR3 TMR5GIP LCDIP RC2IP TX2IP CTMUIP CCP2IP CCP1IP RTCCIP 75 SPEN RX9 SREN CREN ADDEN FERR OERR RX9D 75 RCSTA1 RCREG1 TXSTA1 EUSART1 Receive Register 75 CSRC TX9 TXEN SYNC SENDB BRGH TRMT TX9D 75 BAUDCON1 ABDOVF RCIDL RXDTP TXCKP BRG16 — WUE ABDEN 77 SPBRGH1 EUSART1 Baud Rate Generator Register High Byte SPBRG1 EUSART1 Baud Rate Generator Register Low Byte RCSTA2 RCREG2 TXSTA2 SPEN RX9 SREN 74 75 CREN ADDEN FERR OERR RX9D EUSART2 Receive Register 79 80 CSRC TX9 TXEN SYNC SENDB BRGH TRMT TX9D 79 BAUDCON2 ABDOVF RCIDL RXDTP TXCKP BRG16 — WUE ABDEN 79 SPBRGH2 EUSART2 Baud Rate Generator Register High Byte 80 SPBRG2 EUSART2 Baud Rate Generator Register Low Byte 80 Legend: — = unimplemented, read as ‘0’. Shaded cells are not used for synchronous slave reception. DS39957B-page 370 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 23.0 12-BIT ANALOG-TO-DIGITAL CONVERTER (A/D) MODULE 23.1 The Analog-to-Digital (A/D) Converter module in the PIC18F87K90 family of devices has 16 inputs for the 64-pin devices and 24 inputs for the 80-pin devices. This module allows conversion of an analog input signal to a corresponding signed 12-bit digital number. The module has these registers: • • • • • • • • A/D Control Register 0 (ADCON0) A/D Control Register 1 (ADCON1) A/D Control Register 2 (ADCON2) A/D Port Configuration Register 0 (ANCON0) A/D Port Configuration Register 1 (ANCON1) A/D Port Configuration Register 2 (ANCON2) ADRESH (the upper A/D Results register) ADRESL (the lower A/D Results register) Differential A/D Converter The converter in PIC18F87K90 family devices is implemented as a differential A/D where the differential voltage between two channels is measured and converted to digital values (see Figure 23-1). The converter also can be configured to measure a voltage from a single input by clearing the CHSN bits (ADCON1<2:0>). With this configuration, the negative channel input is connected internally to AVSS (see Figure 23-2). FIGURE 23-1: Positive input CHS<4:0> Negative input CHSN<2:0> The ADCON0 register, shown in Register 23-1, controls the operation of the A/D module. The ADCON1 register, shown in Register 23-2, configures the voltage reference and special trigger selection. The ADCON2 register, shown in Register 23-3, configures the A/D clock source and programmed acquisition time and justification. DIFFERENTIAL CHANNEL MEASUREMENT + – ADC Differential conversion feeds the two input channels to a unity gain differential amplifier. The positive channel input is selected using the CHS bits (ADCON0<6:2>) and the negative channel input is selected using the CHSN bits (ADCON1<2:0>). The output from the amplifier is fed to the A/D convert, as shown in Figure 23-1. The 12-bit result is available on the ADRESH and ADRESL registers. There is also a sign bit, along with the 12-bit result, indicating if the result is a positive or negative value. FIGURE 23-2: Positive input CHS<4:0> CHSN<2:0> = 000 SINGLE CHANNEL MEASUREMENT + – ADC AVSS In the Single Channel Measurement mode, the negative input is connected to AVSS by clearing the CHSN bits (ADCON1<2:0>). 2010 Microchip Technology Inc. Preliminary DS39957B-page 371 PIC18F87K90 FAMILY 23.2 A/D Registers 23.2.1 A/D CONTROL REGISTERS REGISTER 23-1: ADCON0: A/D CONTROL REGISTER 0 U-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 — CHS4 CHS3 CHS2 CHS1 CHS0 GO/DONE ADON bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7 Unimplemented: Read as ‘0’ bit 6-2 CHS<4:0>: Analog Channel Select bits 00000 = Channel 00 (AN0) 00001 = Channel 01 (AN1) 00010 = Channel 02 (AN2) 00011 = Channel 03 (AN3) 00100 = Channel 04 (AN4) 00101 = Channel 05 (AN5) 00110 = Channel 06 (AN6) 00111 = Channel 07 (AN7) 01000 = Channel 08 (AN8) 01001 = Channel 09 (AN9) 01010 = Channel 10 (AN10) 01011 = Channel 11 (AN11) 01100 = Channel 12 (AN12)(1,2) 01101 = Channel 13 (AN13)(1,2) 01110 = Channel 14 (AN14)(1,2) 01111 = Channel 15 (AN15)(1,2) 10000 = 10001 = 10010 = 10011 = 10100 = 10101 = 10110 = 10111 = 11000 = 11001 = 11010 = 11011 = 11100 = 11101 = 11110 = 11111 = x = Bit is unknown Channel 16 (AN16) Channel 17 (AN17) Channel 18 (AN18) Channel 19 (AN19) Channel 20 (AN20)(1,2) Channel 21 (AN21)(1,2) Channel 22 (AN22)(1,2) Channel 23 (AN23)(1,2) (Reserved)(2) (Reserved)(2) (Reserved)(2) (Reserved)(2) Channel 28 (Reserved CTMU) Channel 29 (Internal temperature diode) Channel 30 (VDDCORE) Channel 31 (1.024V band gap) bit 1 GO/DONE: A/D Conversion Status bit 1 = A/D (or calibration) cycle is in progress. Setting this bit starts an A/D conversion cycle. The bit is cleared automatically by hardware when the A/D conversion is completed. 0 = A/D conversion is completed or not in progress bit 0 ADON: A/D On bit 1 = A/D Converter is operating 0 = A/D Converter module is shut off and consuming no operating current Note 1: 2: These channels are not implemented on 64-pin devices. Performing a conversion on unimplemented channels will return random values. DS39957B-page 372 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY REGISTER 23-2: ADCON1: A/D CONTROL REGISTER 1 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 TRIGSEL1 TRIGSEL0 VCFG1 VCFG0 VNCFG CHSN2 CHSN1 CHSN0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7-6 TRIGSEL<1:0>: Special Trigger Select bits 11 = Selects the special trigger from the RTCC 10 = Selects the special trigger from the Timer1 01 = Selects the special trigger from the CTMU 00 = Selects the special trigger from the ECCP2 bit 5-4 VCFG<1:0>: A/D VREF+ Configuration bits 11 = Internal VREF+ (4.096V) 10 = Internal VREF+ (2.048V) 01 = External VREF+ 00 = AVDD bit 3 VNCFG: A/D VREF- Configuration bit 1 = External VREF 0 = AVSS bit 2-0 CHSN<2:0>: Analog Negative Channel Select bits 111 = Channel 07 (AN6) 110 = Channel 06 (AN5) 101 = Channel 05 (AN4) 100 = Channel 04 (AN3) 011 = Channel 03 (AN2) 010 = Channel 02 (AN1) 001 = Channel 01 (AN0) 000 = Selecting ‘000’ chooses AVSS/external VREF- as a negative channel based on VNCFG Note 1: If the A/D FRC clock source is selected, a delay of one TCY (instruction cycle) is added before the A/D clock starts. This allows the SLEEP instruction to be executed before starting a conversion. 2010 Microchip Technology Inc. Preliminary DS39957B-page 373 PIC18F87K90 FAMILY REGISTER 23-3: ADCON2: A/D CONTROL REGISTER 2 R/W-0 U-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 ADFM — ACQT2 ACQT1 ACQT0 ADCS2 ADCS1 ADCS0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7 ADFM: A/D Result Format Select bit 1 = Right justified 0 = Left justified bit 6 Unimplemented: Read as ‘0’ bit 5-3 ACQT<2:0>: A/D Acquisition Time Select bits 111 = 20 TAD 110 = 16 TAD 101 = 12 TAD 100 = 8 TAD 011 = 6 TAD 010 = 4 TAD 001 = 2 TAD 000 = 0 TAD(1) bit 2-0 ADCS<2:0>: A/D Conversion Clock Select bits 111 = FRC (clock derived from A/D RC oscillator)(1) 110 = FOSC/64 101 = FOSC/16 100 = FOSC/4 011 = FRC (clock derived from A/D RC oscillator)(1) 010 = FOSC/32 001 = FOSC/8 000 = FOSC/2 Note 1: x = Bit is unknown If the A/D FRC clock source is selected, a delay of one TCY (instruction cycle) is added before the A/D clock starts. This allows the SLEEP instruction to be executed before starting a conversion. DS39957B-page 374 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 23.2.2 A/D RESULT REGISTERS The ADRESH:ADRESL register pair is where the 12-bit A/D result and extended sign bits (ADSGN) are loaded at the completion of a conversion. This register pair is 16 bits wide. The A/D module gives the flexibility of left or right justifying the 12-bit result in the 16-bit result register. The A/D Format Select bit (ADFM) controls this justification. FIGURE 23-3: Figure 23-3 shows the operation of the A/D result justification and location of the sign bit (ADSGN). The extended sign bits allow for easier 16-bit math to be performed on the result. When the A/D Converter is disabled, these 8-bit registers can be used as two, general purpose registers. A/D RESULT JUSTIFICATION 12-Bit Result Left Justified ADFM = 0 ADRESH Result bits REGISTER 23-4: ADRESL Right Justified ADFM = 1 ADRESH ADRESL ADSGN bit ADRESH: A/D RESULT HIGH BYTE REGISTER, LEFT JUSTIFIED (ADFM = 0) R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x ADRES11 ADRES10 ADRES9 ADRES8 ADRES7 ADRES6 ADRES5 ADRES4 bit 7 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7-0 x = Bit is unknown ADRES<11:4>: A/D Result High Byte bits 2010 Microchip Technology Inc. Preliminary DS39957B-page 375 PIC18F87K90 FAMILY REGISTER 23-5: ADRESL: A/D RESULT LOW BYTE REGISTER, LEFT JUSTIFIED (ADFM = 0) R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x ADRES3 ADRES2 ADRES1 ADRES0 ADSGN ADSGN ADSGN ADSGN bit 7 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7-4 ADRES<3:0>: A/D Result Low Byte bits bit 3-0 ADSGN: A/D Result Sign bits REGISTER 23-6: x = Bit is unknown ADRESH: A/D RESULT HIGH BYTE REGISTER, RIGHT JUSTIFIED (ADFM = 1) R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x ADSGN ADSGN ADSGN ADSGN ADRES11 ADRES10 ADRES9 ADRES8 bit 7 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7-4 ADSGN: A/D Result Sign bits bit 3-0 ADRES<11:8>: A/D Result High Byte bits REGISTER 23-7: x = Bit is unknown ADRESL: A/D RESULT LOW BYTE REGISTER, RIGHT JUSTIFIED (ADFM = 1) R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x ADRES7 ADRES6 ADRES5 ADRES4 ADRES3 ADRES2 ADRES1 ADRES0 bit 7 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7-0 x = Bit is unknown ADRES<7:0>: A/D Result Low Byte bits DS39957B-page 376 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY The ANCONx registers are used to configure the operation of the I/O pin associated with each analog channel. Clearing a ANSELx bit configures the corresponding pin (ANx) to operate as a digital only I/O. Setting a bit configures the pin to operate as an analog input for either the A/D Converter or the comparator module, with all digital peripherals disabled and digital inputs read as ‘0’. REGISTER 23-8: As a rule, I/O pins that are multiplexed with analog inputs default to analog operation on any device Reset. ANCON0: A/D PORT CONFIGURATION REGISTER 0 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 ANSEL7 ANSEL6 ANSEL5 ANSEL4 ANSEL3 ANSEL2 ANSEL1 ANSEL0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7-0 ANSEL<7:0>: Analog Port Configuration bits (AN7 and AN0) 0 = Pin configured as a digital port 1 = Pin configured as an analog channel – digital input disabled and any inputs read as ‘0’ REGISTER 23-9: R/W-1 ANSEL15 x = Bit is unknown (1) ANCON1: A/D PORT CONFIGURATION REGISTER 1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 ANSEL14(1) ANSEL13(1) ANSEL12(1) ANSEL11 ANSEL10 ANSEL9 ANSEL8 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7-0 Note 1: x = Bit is unknown ANSEL<15:8>: Analog Port Configuration bits (AN15 through AN8) 0 = Pin is configured as a digital port 1 = Pin is configured as an analog channel – digital input is disabled and any inputs read as ‘0’ AN12 through AN15, and AN20 to AN23, are implemented only on 80-pin devices. For 64-pin devices, the corresponding ANSELx bits are still implemented for these channels, but have no effect. 2010 Microchip Technology Inc. Preliminary DS39957B-page 377 PIC18F87K90 FAMILY REGISTER 23-10: ANCON2: A/D PORT CONFIGURATION REGISTER 2 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 ANSEL23(1) ANSEL22(1) ANSEL21(1) ANSEL20(1) ANSEL19 ANSEL18 ANSEL17 ANSEL16 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7-0 Note 1: x = Bit is unknown ANSEL<23:16>: Analog Port Configuration bits (AN23 through AN16) 0 = Pin configured as a digital port 1 = Pin configured as an analog channel — digital input disabled and any inputs read as ‘0’ AN12 through AN15, and AN20 to AN23, are implemented only on 80-pin devices. For 64-pin devices, the corresponding ANSELx bits are still implemented for these channels, but have no effect. The analog reference voltage is software-selectable to either the device’s positive and negative supply voltage (AVDD and AVSS) or the voltage level on the RA3/AN3/VREF+ and RA2/AN2/VREF- pins. VREF+ has two additional internal voltage reference selections: 2.048V and 4.096V. The A/D Converter can uniquely operate while the device is in Sleep mode. To operate in Sleep, the A/D conversion clock must be derived from the A/D’s internal RC oscillator. The output of the sample and hold is the input into the converter, which generates the result via successive approximation. the A/D conversion. When the A/D conversion is complete, the result is loaded into the ADRESH:ADRESL register pair, the GO/DONE bit (ADCON0<1>) is cleared and the A/D Interrupt Flag bit, ADIF (PIR1<6>), is set. A device Reset forces all registers to their Reset state. This forces the A/D module to be turned off and any conversion in progress is aborted. The value in the ADRESH:ADRESL register pair is not modified for a Power-on Reset. These registers will contain unknown data after a Power-on Reset. The block diagram of the A/D module is shown in Figure 23-4. Each port pin associated with the A/D Converter can be configured as an analog input or a digital I/O. The ADRESH and ADRESL registers contain the result of DS39957B-page 378 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY FIGURE 23-4: A/D BLOCK DIAGRAM CHS<4:0> 11111 VDDCORE 11101 Reserved Temperature Diode Reserved CTMU 11100 12-Bit A/D Converter 1.024V Band Gap 11110 11011 (Unimplemented) 11010 (Unimplemented) 11001 (Unimplemented) 11000 (Unimplemented) 10111 AN23(1) 10110 AN22(1) 00100 AN4 00011 AN3 00010 AN2 00001 AN1 00000 AN0 CHSN<2:0> Positive Input Voltage 111 Negative Input Voltage AN6 110 Reference Voltage AN5 VCFG<1:0> 11 VREF+ 10 01 VREF- Internal VREF+ (4.096V) 001 Internal VREF+ (2.048V) 000 AN3 00 VNCFG AN0 AVSS VDD AN2 VSS(2) Note 1: Channels, AN12 through AN15, and AN20 through AN23, are not available on 64-pin devices. 2: I/O pins have diode protection to VDD and VSS. 2010 Microchip Technology Inc. Preliminary DS39957B-page 379 PIC18F87K90 FAMILY After the A/D module has been configured as desired, the selected channel must be acquired before the conversion can start. The analog input channels must have their corresponding TRIS bits selected as an input. To determine acquisition time, see Section 23.3 “A/D Acquisition Requirements”. After this acquisition time has elapsed, the A/D conversion can be started. An acquisition time can be programmed to occur between setting the GO/DONE bit and the actual start of the conversion. 2. Configure the A/D interrupt (if desired): • Clear the ADIF bit (PIR1<6>) • Set the ADIE bit (PIE1<6>) • Set the GIE bit (INTCON<7>) Wait the required acquisition time (if required). Start the conversion: • Set the GO/DONE bit (ADCON0<1>) Wait for A/D conversion to complete, by either: • Polling for the GO/DONE bit to be cleared 3. 4. 5. To do an A/D conversion, follow these steps: 1. OR Configure the A/D module: • Configure the required ADC pins as analog pins (ANCON0, ANCON1 and ANCON2) • Set the voltage reference (ADCON1) • Select the A/D positive and negative input channels (ADCON0 and ADCON1) • Select the A/D acquisition time (ADCON2) • Select the A/D conversion clock (ADCON2) • Turn on the A/D module (ADCON0) FIGURE 23-5: • Waiting for the A/D interrupt Read A/D Result registers (ADRESH:ADRESL), and if required, clear bit, ADIF. For the next conversion, begin with step 1 or 2, as required. 6. 7. The A/D conversion time per bit is defined as TAD. Before the next acquisition starts, a minimum wait of 2 TAD is required. ANALOG INPUT MODEL VDD RS VAIN ANx CPIN 5 pF Sampling Switch VT = 0.6V RIC 1k VT = 0.6V SS RSS ILEAKAGE ±100 nA CHOLD = 25 pF VSS Legend: CPIN = Input Capacitance VT = Threshold Voltage ILEAKAGE = Leakage Current at the pin due to various junctions RIC = Interconnect Resistance SS = Sampling Switch CHOLD = Sample/Hold Capacitance (from DAC) RSS = Sampling Switch Resistance DS39957B-page 380 Preliminary VDD 1 2 3 4 Sampling Switch (k) 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 23.3 A/D Acquisition Requirements For the A/D Converter to meet its specified accuracy, the charge holding capacitor (CHOLD) must be allowed to fully charge to the input channel voltage level. The analog input model is shown in Figure 23-5. The source impedance (RS) and the internal sampling switch (RSS) impedance directly affect the time required to charge the capacitor CHOLD. The sampling switch (RSS) impedance varies over the device voltage (VDD). The source impedance affects the offset voltage at the analog input (due to pin leakage current). The maximum recommended impedance for analog sources is 2.5 k. After the analog input channel is selected or changed, the channel must be sampled for at least the minimum acquisition time before starting a conversion. EQUATION 23-1: • • • • • CHOLD Rs Conversion Error VDD Temperature = = = = 25 pF 2.5 k 1/2 LSb 3V Rss = 2 k 85C (system max.) ACQUISITION TIME = Amplifier Settling Time + Holding Capacitor Charging Time + Temperature Coefficient = TAMP + TC + TCOFF EQUATION 23-2: VHOLD or TC Equation 23-3 shows the calculation of the minimum required acquisition time, TACQ. This calculation is based on the following application system assumptions: When the conversion is started, the holding capacitor is disconnected from the input pin. Note: TACQ To calculate the minimum acquisition time, Equation 23-1 can be used. This equation assumes that 1/2 LSb error is used (1,024 steps for the A/D). The 1/2 LSb error is the maximum error allowed for the A/D to meet its specified resolution. A/D MINIMUM CHARGING TIME = (VREF – (VREF/2048)) • (1 – e(-TC/CHOLD(RIC + RSS + RS))) = -(CHOLD)(RIC + RSS + RS) ln(1/2048) EQUATION 23-3: CALCULATING THE MINIMUM REQUIRED ACQUISITION TIME TACQ = TAMP + TC + TCOFF TAMP = 0.2 s TCOFF = (Temp – 25C)(0.02 s/C) (85C – 25C)(0.02 s/C) 1.2 s Temperature coefficient is only required for temperatures > 25C. Below 25C, TCOFF = 0 ms. TC = -(CHOLD)(RIC + RSS + RS) ln(1/2048) s -(25 pF) (1 k + 2 k + 2.5 k) ln(0.0004883) s 1.05 s TACQ = 0.2 s + 1.05 s + 1.2 s 2.45 s 2010 Microchip Technology Inc. Preliminary DS39957B-page 381 PIC18F87K90 FAMILY 23.4 Selecting and Configuring Automatic Acquisition Time TABLE 23-1: AD Clock Source (TAD) The ADCON2 register allows the user to select an acquisition time that occurs each time the GO/DONE bit is set. When the GO/DONE bit is set, sampling is stopped and a conversion begins. The user is responsible for ensuring the required acquisition time has passed between selecting the desired input channel and setting the GO/DONE bit. This occurs when the ACQT<2:0> bits (ADCON2<5:3>) remain in their Reset state (‘000’), which is compatible with devices that do not offer programmable acquisition times. TAD vs. DEVICE OPERATING FREQUENCIES Operation ADCS<2:0> Maximum Device Frequency 2 TOSC 000 2.86 MHz 4 TOSC 100 5.71 MHz 8 TOSC 001 11.43 MHz 16 TOSC 101 22.86 MHz 32 TOSC 010 40.00 MHz 64 TOSC 110 40.00 MHz RC(2) x11 1.00 MHz(1) Note 1: The RC source has a typical TAD time of 4 s. For device frequencies above 1 MHz, the device must be in Sleep mode for the entire conversion or the A/D accuracy may be out of specification. If desired, the ACQTx bits can be set to select a programmable acquisition time for the A/D module. When the GO/DONE bit is set, the A/D module continues to sample the input for the selected acquisition time, then automatically begins a conversion. Since the acquisition time is programmed, there may be no need to wait for an acquisition time between selecting a channel and setting the GO/DONE bit. 23.6 In either case, when the conversion is completed, the GO/DONE bit is cleared, the ADIF flag is set and the A/D begins sampling the currently selected channel again. If an acquisition time is programmed, there is nothing to indicate if the acquisition time has ended or if the conversion has begun. The ANCON0, ANCON1, ANCON2, TRISA, TRISF, TRISG and TRISH registers control the operation of the A/D port pins. The port pins needed as analog inputs must have their corresponding TRISx bits set (input). If the TRISx bit is cleared (output), the digital output level (VOH or VOL) will be converted. 23.5 The A/D operation is independent of the state of the CHS<3:0> bits and the TRISx bits. Selecting the A/D Conversion Clock The A/D conversion time per bit is defined as TAD. The A/D conversion requires 14 TAD per 12-bit conversion. The source of the A/D conversion clock is software-selectable. The possible options for TAD are: • • • • • • • 2 TOSC 4 TOSC 8 TOSC 16 TOSC 32 TOSC 64 TOSC Using the internal RC Oscillator 2: Configuring Analog Port Pins Note 1: When reading the PORT register, all pins configured as analog input channels will read as cleared (a low level). Pins configured as digital inputs will convert an analog input. Analog levels on a digitally configured input will be accurately converted. 2: Analog levels on any pin defined as a digital input may cause the digital input buffer to consume current out of the device’s specification limits. For correct A/D conversions, the A/D conversion clock (TAD) must be as short as possible but greater than the minimum TAD. (For more information, see parameter 130 in Table 31-26.) Table 23-1 shows the resultant TAD times derived from the device operating frequencies and the A/D clock source selected. DS39957B-page 382 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 23.7 A/D Conversions ADRESH:ADRESL registers will continue to contain the value of the last completed conversion (or the last value written to the ADRESH:ADRESL registers). Figure 23-6 shows the operation of the A/D Converter after the GO/DONE bit has been set and the ACQT<2:0> bits are cleared. A conversion is started after the following instruction to allow entry into Sleep mode before the conversion begins. After the A/D conversion is completed or aborted, a 2 TAD wait is required before the next acquisition can be started. After this wait, acquisition on the selected channel is automatically started. Figure 23-7 shows the operation of the A/D Converter after the GO/DONE bit has been set, the ACQT<2:0> bits set to ‘010’ and a 4 TAD acquisition time selected. The GO/DONE bit should NOT be set in the same instruction that turns on the A/D. Note: Clearing the GO/DONE bit during a conversion will abort the current conversion. The A/D Result register pair will NOT be updated with the partially completed A/D conversion sample. This means the FIGURE 23-6: A/D CONVERSION TAD CYCLES (ACQT<2:0> = 000, TACQ = 0) TCY - TAD TAD1 TAD2 TAD3 TAD4 TAD5 TAD6 TAD7 TAD8 b11 b10 b9 b8 b7 b6 b5 TAD9 TAD10 TAD11 TAD12 TAD13 b3 b4 b2 b1 b0 Conversion starts Holding capacitor is disconnected from analog input (typically 100 ns) Set GO/DONE bit Next Q4: ADRESH:ADRESL is loaded, GO/DONE bit is cleared, ADIF bit is set, holding capacitor is connected to analog input. A/D CONVERSION TAD CYCLES (ACQT<2:0> = 010, TACQ = 4 TAD) FIGURE 23-7: TAD Cycles TACQT Cycles 1 2 3 Automatic Acquisition Time 4 1 2 3 4 b11 b10 b9 5 b8 6 7 8 9 10 11 12 13 b7 b6 b5 b4 b3 b2 b1 b0 Conversion starts (Holding capacitor is disconnected) Set GO/DONE bit (Holding capacitor continues acquiring input) 2010 Microchip Technology Inc. Next Q4: ADRESH:ADRESL is loaded, GO/DONE bit is cleared, ADIF bit is set, holding capacitor is reconnected to analog input. Preliminary DS39957B-page 383 PIC18F87K90 FAMILY 23.8 Use of the Special Event Triggers A/D conversion can be started by the Special Event Trigger of any of these modules: • ECCP2 – Requires CCP2M<3:0> bits (CCP2CON<3:0>) set at ‘1011’ • CTMU – Requires the setting of the CTTRIG bit (CTMUCONH<0>) • Timer1 • RTCC • The A/D module must be enabled (ADON = 1) • The appropriate analog input channel selected • The minimum acquisition period set one of these ways: - Timing provided by the user - Selection made of an appropriate TACQ time With these conditions met, the trigger sets the GO/DONE bit and the A/D acquisition starts. If the A/D module is not enabled (ADON = 0), the module ignores the Special Event Trigger. With an ECCP2 trigger, Timer1 or Timer3 is cleared. The timers reset to automatically repeat the A/D acquisition period with minimal software overhead (moving ADRESH:ADRESL to the desired location). If the A/D module is not enabled, the Special Event Trigger is ignored by the module, but the timer’s counter resets. DS39957B-page 384 Operation in Power-Managed Modes The selection of the automatic acquisition time and A/D conversion clock is determined in part by the clock source and frequency while in a power-managed mode. If the A/D is expected to operate while the device is in a power-managed mode, the ACQT<2:0> and ADCS<2:0> bits in ADCON2 should be updated in accordance with the power-managed mode clock that will be used. To start an A/D conversion: Note: 23.9 After the power-managed mode is entered (either of the power-managed Run modes), an A/D acquisition or conversion may be started. Once an acquisition or conversion is started, the device should continue to be clocked by the same power-managed mode clock source until the conversion has been completed. If desired, the device may be placed into the corresponding power-managed Idle mode during the conversion. If the power-managed mode clock frequency is less than 1 MHz, the A/D RC clock source should be selected. Operation in Sleep mode requires that the A/D RC clock be selected. If bits, ACQT<2:0>, are set to ‘000’ and a conversion is started, the conversion will be delayed one instruction cycle to allow execution of the SLEEP instruction and entry into Sleep mode. The IDLEN and SCS<1:0> bits in the OSCCON register must have already been cleared prior to starting the conversion. Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY TABLE 23-2: Name INTCON SUMMARY OF A/D REGISTERS Bit 7 Bit 6 Bit 5 GIE/GIEH PEIE/GIEL TMR0IE Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Reset Values on Page: INT0IE RBIE TMR0IF INT0IF RBIF 73 PIR1 — ADIF RC1IF TX1IF SSP1IF TMR1GIF TMR2IF TMR1IF 75 PIE1 — ADIE RC1IE TX1IE SSP1IE TMR1GIE TMR2IE TMR1IE 75 IPR1 — ADIP RC1IP TX1IP SSP1IP TMR1GIP TMR2IP TMR1IP 75 ADRESH A/D Result Register High Byte 74 ADRESL A/D Result Register Low Byte 74 ADCON0 ADCON1 — CHS4 TRIGSEL1 TRIGSEL0 CHS3 CHS2 CHS1 CHS0 GO/DONE ADON 74 VCFG1 VCFG0 VNCFG CHSN2 CHSN1 CHSN0 74 ADFM — ACQT2 ACQT1 ACQT0 ADCS2 ADCS1 ADCS0 74 ANCON0 ANSEL7 ANSEL6 ANSEL5 ANSEL4 ANSEL3 ANSEL2 ANSEL1 ANSEL0 79 ANCON1 ANSEL15 ANSEL14 ANSEL13 ANSEL12 ANSEL11 ANSEL10 ANSEL9 ANSEL8 79 ANCON2 ANSEL23 ANSEL22 ANSEL21 ANSEL20 ANSEL19 ANSEL18 ANSEL17 ANSEL16 ADCON2 79 CCP2CON P2M1 P2M0 DC2B1 DC2B0 CCP2M3 CCP2M2 CCP2M1 CCP2M0 78 PORTA RA7(2) RA6(2) RA5 RA4 RA3 RA2 RA1 RA0 76 TRISA TRISA7(2) TRISA6(2) TRISA5 TRISA4 TRISA3 TRISA2 TRISA1 TRISA0 76 PORTF RF7 RF6 RF5 RF4 RF3 RF2 RF1 — 76 TRISF TRISF7 TRISF6 TRISF5 TRISF4 TRISF3 TRISF2 TRISF1 — 76 — — RG5/ LATG5(3) RG4 RG3 RG2 RG1 RG0 76 PORTG — — — TRISG4 TRISG3 TRISG2 TRISG1 TRISG0 76 PORTH(1) RH7 RH6 RH5 RH4 RH3 RH2 RH1 RH0 76 TRISH(1) TRISH7 TRISH6 TRISH5 TRISH4 TRISH3 TRISH2 TRISH1 TRISH0 76 TRISG Legend: — = unimplemented, read as ‘0’. Shaded cells are not used for A/D conversion. Note 1: This register is not implemented on 64-pin devices. 2: These bits are available only in certain oscillator modes, when the OSC2 Configuration bit = 0. If that Configuration bit is cleared, this signal is not implemented. 3: Bit is available when Master Clear is disabled (MCLRE = 0). When MCLRE is set, bit is unimplemented. 2010 Microchip Technology Inc. Preliminary DS39957B-page 385 PIC18F87K90 FAMILY NOTES: DS39957B-page 386 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 24.0 COMPARATOR MODULE 24.1 The analog comparator module contains three comparators that can be independently configured in a variety of ways. The inputs can be selected from the analog inputs and two internal voltage references. The digital outputs are available at the pin level and can also be read through the control register. Multiple output and interrupt event generation are also available. A generic single comparator from the module is shown in Figure 24-1. Registers The CMxCON registers (CM1CON, CM2CON and CM3CON) select the input and output configuration for each comparator, as well as the settings for interrupt generation (see Register 24-1). The CMSTAT register (Register 24-2) provides the output results of the comparators. The bits in this register are read-only. Key features of the module includes: • • • • • Independent comparator control Programmable input configuration Output to both pin and register levels Programmable output polarity Independent interrupt generation for each comparator with configurable interrupt-on-change FIGURE 24-1: COMPARATOR SIMPLIFIED BLOCK DIAGRAM CMPxOUT (CMSTAT<7:5>) CCH<1:0> CxINB 0 CxINC(2) 1 (1,2) 2 VBG 3 C2INB/C2IND Interrupt Logic CMPxIF EVPOL<1:0> CREF COE VIN- CxINA 0 CVREF 1 Note 1: 2: VIN+ Cx Polarity Logic CON CPOL CxOUT Comparators, 1 and 3, use C2INB as an input to the inverting terminal. Comparator 2 uses C2IND as an input to the inverted terminal. C1INC, C2INC and C2IND are all unavailable on 64-pin devices (PIC18F6XK90). 2010 Microchip Technology Inc. Preliminary DS39957B-page 387 PIC18F87K90 FAMILY REGISTER 24-1: CMxCON: COMPARATOR CONTROL x REGISTER R/W-0 R/W-0 R/W-0 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 CON COE CPOL EVPOL1 EVPOL0 CREF CCH1 CCH0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 CON: Comparator Enable bit 1 = Comparator is enabled 0 = Comparator is disabled bit 6 COE: Comparator Output Enable bit 1 = Comparator output is present on the CxOUT pin 0 = Comparator output is internal only bit 5 CPOL: Comparator Output Polarity Select bit 1 = Comparator output is inverted 0 = Comparator output is not inverted bit 4-3 EVPOL<1:0>: Interrupt Polarity Select bits 11 = Interrupt generation on any change of the output(1) 10 = Interrupt generation only on high-to-low transition of the output 01 = Interrupt generation only on low-to-high transition of the output 00 = Interrupt generation is disabled bit 2 CREF: Comparator Reference Select bit (non-inverting input) 1 = Non-inverting input connects to the internal CVREF voltage 0 = Non-inverting input connects to the CxINA pin bit 1-0 CCH<1:0>: Comparator Channel Select bits 11 = Inverting input of comparator connects to VBG 10 = Inverting input of comparator connects to the C2INB or C2IND pin(2,3) 01 = Inverting input of comparator connects to the CxINC pin(3) 00 = Inverting input of comparator connects to the CxINB pin Note 1: 2: 3: The CMPxIF bit is automatically set any time this mode is selected and must be cleared by the application after the initial configuration. Comparators, 1 and 3, use C2INB as an input to the inverting terminal; Comparator 2 uses C2IND. 3: C1INC, C2INC and C2IND are all unavailable for 64-pin devices (PIC18F6XK90). DS39957B-page 388 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY REGISTER 24-2: CMSTAT: COMPARATOR STATUS REGISTER R-1 R-1 R-1 U-0 U-0 U-0 U-0 U-0 CMP3OUT CMP2OUT CMP1OUT — — — — — bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7-5 CMPxOUT<3:1>: Comparator x Status bits If CPOL (CMxCON<5>)= 0 (non-inverted polarity): 1 = Comparator x’s VIN+ > VIN0 = Comparator x’s VIN+ < VINIf CPOL = 1 (inverted polarity): 1 = Comparator x’s VIN+ < VIN0 = Comparator x’s VIN+ > VIN- bit 4-0 Unimplemented: Read as ‘0’ 2010 Microchip Technology Inc. Preliminary x = Bit is unknown DS39957B-page 389 PIC18F87K90 FAMILY 24.2 Comparator Operation 24.3 Comparator Response Time A single comparator is shown in Figure 24-2, along with the relationship between the analog input levels and the digital output. When the analog input at VIN+ is less than the analog input, VIN-, the output of the comparator is a digital low level. When the analog input at VIN+ is greater than the analog input, VIN-, the output of the comparator is a digital high level. The shaded areas of the output of the comparator in Figure 24-2 represent the uncertainty due to input offsets and response time. Response time is the minimum time, after selecting a new reference voltage or input source, before the comparator output has a valid level. The response time of the comparator differs from the settling time of the voltage reference. Therefore, both of these times must be considered when determining the total response to a comparator input change. Otherwise, the maximum delay of the comparators should be used (see Section 31.0 “Electrical Characteristics”). FIGURE 24-2: SINGLE COMPARATOR 24.4 – A simplified circuit for an analog input is shown in Figure 24-3. Since the analog pins are connected to a digital output, they have reverse biased diodes to VDD and VSS. The analog input, therefore, must be between VSS and VDD. If the input voltage deviates from this range by more than 0.6V in either direction, one of the diodes is forward biased and a latch-up condition may occur. VIN- Output + VIN+ VIN- Analog Input Connection Considerations A maximum source impedance of 10 k is recommended for the analog sources. Any external component connected to an analog input pin, such as a capacitor or a Zener diode, should have very little leakage current. VIN+ Output FIGURE 24-3: COMPARATOR ANALOG INPUT MODEL VDD VT = 0.6V RS <10k AIN CPIN 5 pF VA VT = 0.6V RIC Comparator Input ILEAKAGE ±100 nA VSS Legend: DS39957B-page 390 CPIN VT ILEAKAGE RIC RS VA = = = = = = Input Capacitance Threshold Voltage Leakage Current at the pin due to various junctions Interconnect Resistance Source Impedance Analog Voltage Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 24.5 Comparator Control and Configuration Each comparator has up to eight possible combinations of inputs: up to four external analog inputs and one of two internal voltage references. All of the comparators allow a selection of the signal from pin, CxINA, or the voltage from the Comparator Voltage Reference (CVREF) on the non-inverting channel. This is compared to either CxINB, CxINC, C2INB/C2IND or the microcontroller’s fixed internal reference voltage (VBG, 1.024V nominal) on the inverting channel. The comparator inputs and outputs are tied to fixed I/O pins, defined in Table 24-1. The available comparator configurations and their corresponding bit settings are shown in Figure 24-4. TABLE 24-1: Comparator 1 2 3 Note 1: 24.5.1 COMPARATOR INPUTS AND OUTPUTS Input or Output I/O Pin C1INA (VIN+) RF6 C1INB (VIN-) RF5 C1INC(1) (VIN-) RH6 C2INB (VIN-) RF3 C1OUT RF2 C2INA (VIN+) RF4 C2INB (VIN-) RF3 (1) (VIN-) C2INC RH4 C2IND(1) (VIN-) RH5 C2OUT RF1 C3INA (VIN+) RG2 C3INB (VIN-) RG3 C3INC (VIN-) RG4 C2INB (VIN-) RF3 C3OUT RG1 The analog signal present at VIN- is compared to the signal at VIN+ and the digital output of the comparator is adjusted accordingly. The external reference is used when CREF = 0 (CMxCON<2>) and VIN+ is connected to the CxINA pin. When external voltage references are used, the comparator module can be configured to have the reference sources externally. The reference signal must be between VSS and VDD and can be applied to either pin of the comparator. The comparator module also allows the selection of an internally generated voltage reference from the Comparator Voltage Reference (CVREF) module. This module is described in more detail in Section 25.0 “Comparator Voltage Reference Module”. The reference from the comparator voltage reference module is only available when CREF = 1. In this mode, the internal voltage reference is applied to the comparator’s VIN+ pin. Note: 24.5.2 The comparator input pin selected by CCH<1:0> must be configured as an input by setting both the corresponding TRISF, TRISG or TRISH bit and the corresponding ANSELx bit in the ANCONx register. COMPARATOR ENABLE AND OUTPUT SELECTION The comparator outputs are read through the CMSTAT register. The CMSTAT<5> bit reads the Comparator 1 output, CMSTAT<6> reads Comparator 2 output and CMSTAT<7> reads Comparator 3 output. These bits are read-only. The comparator outputs may also be directly output to the RF2, RF1 and RG1 I/O pins by setting the COE bit (CMxCON<6>). When enabled, multiplexers in the output path of the pins switch to the output of the comparator. While in this mode, the TRISF<2:1> and TRISG<1> bits still function as the digital output enable bits for the RF2, RF1 and RG1 pins. C1INC, C2INC and C2IND are all unavailable for 64-pin devices (PIC18F6XK90). COMPARATOR ENABLE AND INPUT SELECTION Setting the CON bit of the CMxCON register (CMxCON<7>) enables the comparator for operation. Clearing the CON bit disables the comparator, resulting in minimum current consumption. The CCH<1:0> bits in the CMxCON register (CMxCON<1:0>) direct either one of three analog input pins, or the Internal Reference Voltage (VBG), to the comparator, VIN-. Depending on the comparator 2010 Microchip Technology Inc. operating mode, either an external or internal voltage reference may be used. For external analog pins that are unavailable in 64-pin devices (C1INC, C2INC and C2IND), the corresponding configurations that use them as inputs are unavailable. By default, the comparator’s output is at logic high whenever the voltage on VIN+ is greater than on VIN-. The polarity of the comparator outputs can be inverted using the CPOL bit (CMxCON<5>). The uncertainty of each of the comparators is related to the input offset voltage and the response time given in the specifications, as discussed in Section 24.2 “Comparator Operation”. Preliminary DS39957B-page 391 PIC18F87K90 FAMILY FIGURE 24-4: COMPARATOR CONFIGURATIONS Comparator Off CON = 0, CREF = x, CCH<1:0> = xx COE VINCx VIN+ Off (Read as ‘0’) CxOUT Pin Comparator CxINC > CxINA Compare(2,3) CON = 1, CREF = 0, CCH<1:0> = 01 Comparator CxINB > CxINA Compare CON = 1, CREF = 0, CCH<1:0> = 00 COE CxINB CxINA COE VINVIN+ CxINC Cx CxOUT Pin Comparator CxIND > CxINA Compare(3) CON = 1, CREF = 0, CCH<1:0> = 10 CxINA VINVIN+ Cx CxOUT Pin Comparator VIRV > CxINA Compare CON = 1, CREF = 0, CCH<1:0> = 11 COE C2INB/ C2IND CxINA COE VINVIN+ VBG(1) Cx CxOUT Pin CxINA VINVIN+ Cx CxOUT Pin Comparator CxINC > CVREF Compare(2,3) CON = 1, CREF = 1, CCH<1:0> = 01 Comparator CxINB > CVREF Compare CON = 1, CREF = 1, CCH<1:0> = 00 COE CxINB CVREF COE VINVIN+ CxINC Cx CxOUT Pin Comparator CxIND > CVREF Compare(3) CON = 1, CREF = 1, CCH<1:0> = 10 CVREF VINVIN+ Cx Comparator VIRV > CVREF Compare CON = 1, CREF = 1, CCH<1:0> = 11 COE CxINB/ CxIND CVREF Note 1: 2: 3: COE VINVIN+ VBG(1) Cx CxOUT Pin CxOUT Pin CVREF VINVIN+ Cx CxOUT Pin VBG is the Internal Reference Voltage (1.024V nominal). Configuration is unavailable for CM1CON on 64-pin devices (PIC18F6XK90). Configuration is unavailable for CM2CON on 64-pin devices (PIC18F6XK90). DS39957B-page 392 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 24.6 Comparator Interrupts The comparator interrupt flag is set whenever any of the following occurs: • Low-to-high transition of the comparator output • High-to-low transition of the comparator output • Any change in the comparator output The comparator interrupt selection is done by the EVPOL<1:0> bits in the CMxCON register (CMxCON<4:3>). In order to provide maximum flexibility, the output of the comparator may be inverted using the CPOL bit in the CMxCON register (CMxCON<5>). This is functionally identical to reversing the inverting and non-inverting inputs of the comparator for a particular mode. An interrupt is generated on the low-to-high or high-tolow transition of the comparator output. This mode of interrupt generation is dependent on EVPOL<1:0> in the CMxCON register. When EVPOL<1:0> = 01 or 10, the interrupt is generated on a low-to-high or high-tolow transition of the comparator output. Once the interrupt is generated, it is required to clear the interrupt flag by software. TABLE 24-2: CPOL When EVPOL<1:0> = 11, the comparator interrupt flag is set whenever there is a change in the output value of either comparator. Software will need to maintain information about the status of the output bits, as read from CMSTAT<7:5>, to determine the actual change that occurred. The CMPxIF bits (PIR6<2:0>) are the Comparator Interrupt Flags. The CMPxIF bits must be reset by clearing them. Since it is also possible to write a ‘1’ to this register, a simulated interrupt may be initiated. Table 24-2 shows the interrupt generation with respect to comparator input voltages and EVPOL bit settings. Both the CMPxIE bits (PIE6<2:0>) and the PEIE bit (INTCON<6>) must be set to enable the interrupt. In addition, the GIE bit (INTCON<7>) must also be set. If any of these bits are clear, the interrupt is not enabled, though the CMPxIF bits will still be set if an interrupt condition occurs. A simplified diagram of the interrupt section is shown in Figure 24-3. Note: CMPxIF will not be set when EVPOL<1:0> = 00. COMPARATOR INTERRUPT GENERATION EVPOL<1:0> 00 01 0 10 11 00 01 1 10 11 2010 Microchip Technology Inc. Comparator Input Change CxOUT Transition VIN+ > VIN- Low-to-High No VIN+ < VIN- High-to-Low No VIN+ > VIN- Low-to-High Yes VIN+ < VIN- High-to-Low No VIN+ > VIN- Low-to-High No VIN+ < VIN- High-to-Low Yes VIN+ > VIN- Low-to-High Yes VIN+ < VIN- High-to-Low Yes VIN+ > VIN- High-to-Low No VIN+ < VIN- Low-to-High No VIN+ > VIN- High-to-Low No VIN+ < VIN- Low-to-High Yes VIN+ > VIN- High-to-Low Yes VIN+ < VIN- Low-to-High No VIN+ > VIN- High-to-Low Yes VIN+ < VIN- Low-to-High Yes Preliminary Interrupt Generated DS39957B-page 393 PIC18F87K90 FAMILY 24.7 Comparator Operation During Sleep To minimize power consumption while in Sleep mode, turn off the comparators (CON = 0) before entering Sleep. If the device wakes up from Sleep, the contents of the CMxCON register are not affected. When a comparator is active and the device is placed in Sleep mode, the comparator remains active and the interrupt is functional, if enabled. This interrupt will wake-up the device from Sleep mode, when enabled. Each operational comparator will consume additional current. TABLE 24-3: Name INTCON 24.8 Effects of a Reset A device Reset forces the CMxCON registers to their Reset state. This forces both comparators and the voltage reference to the OFF state. REGISTERS ASSOCIATED WITH COMPARATOR MODULE Bit 7 Bit 6 GIE/GIEH PEIE/GIEL Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Reset Values on Page: TMR0IE INT0IE RBIE TMR0IF INT0IF RBIF 73 PIR6 — — — EEIF — CMP3IF CMP2IF CMP1IF 75 PIE6 — — — EEIE — CMP3IE CMP2IE CMP1IE 78 — — — EEIP — CMP3IP CMP2IP CMP1IP 75 CM1CON CON COE CPOL EVPOL1 EVPOL0 CREF CCH1 CCH0 78 CM2CON CON COE CPOL EVPOL1 EVPOL0 CREF CCH1 CCH0 79 CM3CON CON COE CPOL EVPOL1 EVPOL0 CREF CCH1 CCH0 79 CVRCON CVREN CVROE CVRSS CVR4 CVR3 CVR2 CVR1 CVR0 75 — — — — — 75 IPR6 CMSTAT CMP3OUT CMP2OUT CMP1OUT RF7 RF6 RF5 RF4 RF3 RF2 RF1 — 76 LATF LATF7 LATF6 LATF5 LATF4 LATF3 LATF2 LATF1 — 76 TRISF PORTF TRISF7 TRISF6 TRISF5 TRISF4 TRISF3 TRISF2 TRISF1 — 76 PORTG — — RG5 RG4 RG3 RG2 RG1 RG0 76 LATG — — — LATG4 LATG3 LATG2 LATG1 LATG0 76 TRISG — — — TRISG4 TRISG3 TRISG2 TRISG1 TRISG0 76 PORTH LATH TRISH Legend: RH7 RH6 RH5 RH4 RH3 RH2 RH1 RH0 76 LATH7 LATH6 LATH5 LATH4 LATH3 LATH2 LATH1 LATH0 76 TRISH7 TRISH6 TRISH5 TRISH4 TRISH3 TRISH2 TRISH1 TRISH0 76 — = unimplemented, read as ‘0’. DS39957B-page 394 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 25.0 COMPARATOR VOLTAGE REFERENCE MODULE EQUATION 25-1: If CVRSS = 1: The comparator voltage reference is a 32-tap resistor ladder network that provides a selectable reference voltage. Although its primary purpose is to provide a reference for the analog comparators, it may also be used independently of them. A block diagram of the module is shown in Figure 25-1. The resistor ladder is segmented to provide a range of CVREF values and has a power-down function to conserve power when the reference is not being used. The module’s supply reference can be provided from either device VDD/VSS or an external voltage reference. 25.1 Configuring the Comparator Voltage Reference The comparator voltage reference module is controlled through the CVRCON register (Register 25-1). The comparator voltage reference provides a range of output voltage with 32 levels. CVREF = (VREF-) + (CVR<4:0>/32) • (VREF+ – VREF-) If CVRSS = 0: CVREF = (AVSS) + (CVR<4:0>/32) • (AVDD – AVSS) The comparator reference supply voltage can come from either VDD and VSS, or the external VREF+ and VREF- that are multiplexed with RA3 and RA2. The voltage source is selected by the CVRSS bit (CVRCON<5>). The settling time of the comparator voltage reference must be considered when changing the CVREF output (see Table 31-2 in Section 31.0 “Electrical Characteristics”). The CVR<4:0> selection bits (CVRCON<4:0>) offer a range of output voltages. Equation 25-1 shows how the comparator voltage reference is computed. REGISTER 25-1: CVRCON: COMPARATOR VOLTAGE REFERENCE CONTROL REGISTER R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 CVREN CVROE CVRSS CVR4 CVR3 CVR2 CVR1 CVR0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7 CVREN: Comparator Voltage Reference Enable bit 1 = CVREF circuit is powered on 0 = CVREF circuit is powered down bit 6 CVROE: Comparator VREF Output Enable bit 1 = CVREF voltage level is output on the CVREF pin 0 = CVREF voltage level is disconnected from the CVREF pin bit 5 CVRSS: Comparator VREF Source Selection bit 1 = Comparator reference source, CVRSRC = VREF+ – VREF0 = Comparator reference source, CVRSRC = AVDD – AVSS bit 4-0 CVR<4:0>: Comparator VREF Value Selection (0 CVR<4:0> 31) bits When CVRSS = 1: CVREF = (VREF-) + (CVR<4:0>/32) (VREF+ – VREF-) When CVRSS = 0: CVREF = (AVSS) + (CVR<4:0>/32) (AVDD – AVSS) 2010 Microchip Technology Inc. Preliminary x = Bit is unknown DS39957B-page 395 PIC18F87K90 FAMILY FIGURE 25-1: COMPARATOR VOLTAGE REFERENCE BLOCK DIAGRAM VREF+ AVDD CVRSS = 1 8R CVRSS = 0 CVR<4:0> R CVREN R R 32-to-1 MUX R 32 Steps R CVREF R R VREF- CVRSS = 1 CVRSS = 0 25.2 Voltage Reference Accuracy/Error The full range of voltage reference cannot be realized due to the construction of the module. The transistors on the top and bottom of the resistor ladder network (Figure 25-1) keep CVREF from approaching the reference source rails. The voltage reference is derived from the reference source; therefore, the CVREF output changes with fluctuations in that source. The tested absolute accuracy of the voltage reference can be found in Section 31.0 “Electrical Characteristics”. 25.3 Operation During Sleep When the device wakes up from Sleep through an interrupt or a Watchdog Timer time-out, the contents of the CVRCON register are not affected. To minimize current consumption in Sleep mode, the voltage reference should be disabled. DS39957B-page 396 25.4 Effects of a Reset A device Reset disables the voltage reference by clearing bit, CVREN (CVRCON<7>). This Reset also disconnects the reference from the RF5 pin by clearing bit, CVROE (CVRCON<6>). 25.5 Connection Considerations The voltage reference module operates independently of the comparator module. The output of the reference generator may be connected to the RF5 pin if the CVROE bit is set. Enabling the voltage reference output onto RF5 when it is configured as a digital input will increase current consumption. Connecting RF5 as a digital output with CVRSS enabled will also increase current consumption. The RF5 pin can be used as a simple D/A output with limited drive capability. Due to the limited current drive capability, a buffer must be used on the voltage reference output for external connections to VREF. Figure 25-2 shows an example buffering technique. Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY FIGURE 25-2: COMPARATOR VOLTAGE REFERENCE OUTPUT BUFFER EXAMPLE PIC18F87K90 CVREF Module R(1) Voltage Reference Output Impedance Note 1: TABLE 25-1: + – RF5 CVREF Output R is dependent upon the Voltage Reference Configuration bits, CVRCON<3:0> and CVRCON<5>. REGISTERS ASSOCIATED WITH COMPARATOR VOLTAGE REFERENCE Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Reset Values on Page: CVRCON CVREN CVROE CVRSS CVR4 CVR3 CVR2 CVR1 CVR0 75 CM1CON CON COE CPOL EVPOL1 EVPOL0 CREF CCH1 CCH0 78 CM2CON CON COE CPOL EVPOL1 EVPOL0 CREF CCH1 CCH0 79 Name CM3CON TRISF CON COE CPOL EVPOL1 EVPOL0 CREF CCH1 CCH0 79 TRISF7 TRISF6 TRISF5 TRISF4 TRISF3 TRISF2 TRISF1 — 76 Legend: — = unimplemented, read as ‘0’. Shaded cells are not used with the comparator voltage reference. 2010 Microchip Technology Inc. Preliminary DS39957B-page 397 PIC18F87K90 FAMILY NOTES: DS39957B-page 398 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 26.0 HIGH/LOW-VOLTAGE DETECT (HLVD) The PIC18F87K90 family of devices has a High/LowVoltage Detect module (HLVD). This is a programmable circuit that sets both a device voltage trip point and the direction of change from that point. If the device experiences an excursion past the trip point in that direction, an interrupt flag is set. If the interrupt is enabled, the program execution branches to the interrupt vector address and the software responds to the interrupt. REGISTER 26-1: R/W-0 The module’s block diagram is shown in Figure 26-1. HLVDCON: HIGH/LOW-VOLTAGE DETECT CONTROL REGISTER R-0 VDIRMAG The High/Low-Voltage Detect Control register (Register 26-1) completely controls the operation of the HLVD module. This allows the circuitry to be “turned off” by the user under software control, which minimizes the current consumption for the device. BGVST R-0 IRVST R/W-0 HLVDEN R/W-0 (1) HLVDL3 R/W-1 HLVDL2 (1) R/W-0 HLVDL1 (1) R/W-0 HLVDL0(1) bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 VDIRMAG: Voltage Direction Magnitude Select bit 1 = Event occurs when voltage equals or exceeds trip point (HLVDL<3:0>) 0 = Event occurs when voltage equals or falls below trip point (HLVDL<3:0>) bit 6 BGVST: Band Gap Reference Voltages Stable Status Flag bit 1 = Internal band gap voltage references are stable 0 = Internal band gap voltage references are not stable bit 5 IRVST: Internal Reference Voltage Stable Flag bit 1 = Indicates that the voltage detect logic will generate the interrupt flag at the specified voltage range 0 = Indicates that the voltage detect logic will not generate the interrupt flag at the specified voltage range and the HLVD interrupt should not be enabled bit 4 HLVDEN: High/Low-Voltage Detect Power Enable bit 1 = HLVD is enabled 0 = HLVD is disabled bit 3-0 HLVDL<3:0>: Voltage Detection Limit bits(1) 1111 = External analog input is used (input comes from the HLVDIN pin) 1110 = Maximum setting . . . 0000 = Minimum setting Note 1: For the electrical specifications, see parameter D420. 2010 Microchip Technology Inc. Preliminary DS39957B-page 399 PIC18F87K90 FAMILY The module is enabled by setting the HLVDEN bit (HLVDCON<4>). Each time the HLVD module is enabled, the circuitry requires some time to stabilize. The IRVST bit (HLVDCON<5>) is a read-only bit used to indicate when the circuit is stable. The module can only generate an interrupt after the circuit is stable and IRVST is set. trip point voltage. The “trip point” voltage is the voltage level at which the device detects a high or low-voltage event, depending on the configuration of the module. When the supply voltage is equal to the trip point, the voltage tapped off of the resistor array is equal to the internal reference voltage generated by the voltage reference module. The comparator then generates an interrupt signal by setting the HLVDIF bit. The VDIRMAG bit (HLVDCON<7>) determines the overall operation of the module. When VDIRMAG is cleared, the module monitors for drops in VDD below a predetermined set point. When the bit is set, the module monitors for rises in VDD above the set point. 26.1 The trip point voltage is software programmable to any of 16 values. The trip point is selected by programming the HLVDL<3:0> bits (HLVDCON<3:0>). The HLVD module has an additional feature that allows the user to supply the trip voltage to the module from an external source. This mode is enabled when bits, HLVDL<3:0>, are set to ‘1111’. In this state, the comparator input is multiplexed from the external input pin, HLVDIN. This gives users the flexibility of configuring the High/Low-Voltage Detect interrupt to occur at any voltage in the valid operating range. Operation When the HLVD module is enabled, a comparator uses an internally generated reference voltage as the set point. The set point is compared with the trip point, where each node in the resistor divider represents a FIGURE 26-1: VDD HLVD MODULE BLOCK DIAGRAM (WITH EXTERNAL INPUT) Externally Generated Trip Point VDD HLVDL<3:0> HLVDCON Register HLVDEN HLVDIN VDIRMAG 16-to-1 MUX Set HLVDIF HLVDEN BOREN DS39957B-page 400 Internal Voltage Reference 1.024V Typical Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 26.2 HLVD Setup Depending on the application, the HLVD module does not need to operate constantly. To reduce current requirements, the HLVD circuitry may only need to be enabled for short periods where the voltage is checked. After such a check, the module could be disabled. To set up the HLVD module: 1. 2. 3. 4. 5. Select the desired HLVD trip point by writing the value to the HLVDL<3:0> bits. Set the VDIRMAG bit to detect high voltage (VDIRMAG = 1) or low voltage (VDIRMAG = 0). Enable the HLVD module by setting the HLVDEN bit. Clear the HLVD interrupt flag (PIR2<2>), which may have been set from a previous interrupt. If interrupts are desired, enable the HLVD interrupt by setting the HLVDIE and GIE bits (PIE2<2> and INTCON<7>, respectively). 26.4 The internal reference voltage of the HLVD module, specified in electrical specification parameter 37 (Section 31.0 “Electrical Characteristics”), may be used by other internal circuitry, such as the programmable Brown-out Reset. If the HLVD or other circuits using the voltage reference are disabled to lower the device’s current consumption, the reference voltage circuit will require time to become stable before a low or high-voltage condition can be reliably detected. This start-up time, TIRVST, is an interval that is independent of device clock speed. It is specified in electrical specification parameter 36 (Table 31-10). An interrupt will not be generated until the IRVST bit is set. Note: 26.3 HLVD Start-up Time Before changing any module settings (VDIRMAG, HLVDL<3:0>), first disable the module (HLVDEN = 0), make the changes and re-enable the module. This prevents the generation of false HLVD events. The HLVD interrupt flag is not enabled until TIRVST has expired and a stable reference voltage is reached. For this reason, brief excursions beyond the set point may not be detected during this interval (see Figure 26-2 or Figure 26-3). Current Consumption When the module is enabled, the HLVD comparator and voltage divider are enabled and consume static current. The total current consumption, when enabled, is specified in electrical specification parameter D022B (Table 31-10). FIGURE 26-2: LOW-VOLTAGE DETECT OPERATION (VDIRMAG = 0) CASE 1: HLVDIF may Not be Set VDD VHLVD HLVDIF Enable HLVD TIRVST IRVST Internal Reference is Stable CASE 2: HLVDIF Cleared in Software VDD VHLVD HLVDIF Enable HLVD TIRVST IRVST HLVDIF Cleared in Software Internal Reference is Stable HLVDIF Cleared in Software, HLVDIF Remains Set since HLVD Condition still Exists 2010 Microchip Technology Inc. Preliminary DS39957B-page 401 PIC18F87K90 FAMILY FIGURE 26-3: HIGH-VOLTAGE DETECT OPERATION (VDIRMAG = 1) CASE 1: HLVDIF may Not be Set VHLVD VDD HLVDIF Enable HLVD TIRVST IRVST HLVDIF Cleared in Software Internal Reference is Stable CASE 2: VHLVD VDD HLVDIF Enable HLVD TIRVST IRVST Internal Reference is Stable HLVDIF Cleared in Software HLVDIF Cleared in Software, HLVDIF remains Set since HLVD Condition still Exists Applications FIGURE 26-4: In many applications, it is desirable to detect a drop below, or rise above, a particular voltage threshold. For example, the HLVD module could be periodically enabled to detect Universal Serial Bus (USB) attach or detach. This assumes the device is powered by a lower voltage source than the USB when detached. An attach would indicate a high-voltage detect from, for example, 3.3V to 5V (the voltage on USB) and vice versa for a detach. This feature could save a design a few extra components and an attach signal (input pin). VA VB For general battery applications, Figure 26-4 shows a possible voltage curve. Over time, the device voltage decreases. When the device voltage reaches voltage, VA, the HLVD logic generates an interrupt at time, TA. The interrupt could cause the execution of an ISR, which would allow the application to perform “housekeeping tasks” and a controlled shutdown before the device voltage exits the valid operating range at TB. This would give the application a time window, represented by the difference between TA and TB, to safely exit. DS39957B-page 402 TYPICAL LOW-VOLTAGE DETECT APPLICATION Voltage 26.5 Preliminary Time TA TB Legend: VA = HLVD trip point VB = Minimum valid device operating voltage 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 26.6 Operation During Sleep 26.7 When enabled, the HLVD circuitry continues to operate during Sleep. If the device voltage crosses the trip point, the HLVDIF bit will be set and the device will wake-up from Sleep. Device execution will continue from the interrupt vector address if interrupts have been globally enabled. TABLE 26-1: Name A device Reset forces all registers to their Reset state. This forces the HLVD module to be turned off. REGISTERS ASSOCIATED WITH HIGH/LOW-VOLTAGE DETECT MODULE Bit 7 HLVDCON VDIRMAG INTCON Effects of a Reset Bit 6 BGVST GIE/GIEH PEIE/GIEL Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Reset Values on Page: IRVST HLVDEN HLVDL3 HLVDL2 HLVDL1 HLVDL0 75 TMR0IE INT0IE RBIE TMR0IF INT0IF RBIF 73 PIR2 OSCFIF — SSP2IF BLC2IF BCL1IF HLVDIF TMR3IF TMR3GIF 75 PIE2 OSCFIE — SSP2IE BLC2IE BCL1IE HLVDIE TMR3IE TMR3GIE 75 OSCFIP — SSP2IP BLC2IP BCL1IP HLVDIP TMR3IP TMR3GIP 75 TRISA7(1) TRISA6(1) TRISA5 TRISA4 TRISA3 TRISA2 TRISA1 TRISA0 76 IPR2 TRISA Legend: — = unimplemented, read as ‘0’. Shaded cells are unused by the HLVD module. Note 1: PORTA<7:6> and their direction bits are individually configured as port pins based on various primary oscillator modes. When disabled, these bits read as ‘0’. 2010 Microchip Technology Inc. Preliminary DS39957B-page 403 PIC18F87K90 FAMILY NOTES: DS39957B-page 404 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 27.0 CHARGE TIME MEASUREMENT UNIT (CTMU) • • • • Control of response to edges Time measurement resolution of 1 nanosecond High-precision time measurement Time delay of external or internal signal asynchronous to system clock • Accurate current source suitable for capacitive measurement The Charge Time Measurement Unit (CTMU) is a flexible analog module that provides accurate differential time measurement between pulse sources, as well as asynchronous pulse generation. By working with other on-chip analog modules, the CTMU can precisely measure time, capacitance and relative changes in capacitance or generate output pulses with a specific time delay. The CTMU is ideal for interfacing with capacitive-based sensors. The CTMU works in conjunction with the A/D Converter to provide up to 24 channels for time or charge measurement, depending on the specific device and the number of A/D channels available. When configured for time delay, the CTMU is connected to one of the analog comparators. The level-sensitive input edge sources can be selected from four sources: two external inputs or the ECCP1/ECCP2 Special Event Triggers. The module includes these key features: • Up to 24 channels available for capacitive or time measurement input • On-chip precision current source • Four-edge input trigger sources • Polarity control for each edge source • Control of edge sequence FIGURE 27-1: The CTMU special event can trigger the Analog-to-Digital Converter module. Figure 27-1 provides a block diagram of the CTMU. CTMU BLOCK DIAGRAM CTMUCON EDGEN EDGSEQEN EDG1SELx EDG1POL EDG2SELx EDG2POL CTEDG1 CTEDG2 CTMUICON ITRIM<5:0> IRNG<1:0> EDG1STAT EDG2STAT Edge Control Logic Current Source Current Control ECCP2 TGEN IDISSEN CTTRIG CTMU Control Logic Pulse Generator ECCP1 A/D Converter A/D Trigger CTPLS Comparator 2 Input Comparator 2 Output 2010 Microchip Technology Inc. Preliminary DS39957B-page 405 PIC18F87K90 FAMILY 27.1 CTMU Registers The CTMUCONH and CTMUCONL registers (Register 27-1 and Register 27-2) contain control bits for configuring the CTMU module edge source selection, edge source polarity selection, edge sequencing, A/D trigger, analog circuit capacitor discharge and enables. The CTMUICON register (Register 27-3) has bits for selecting the current source range and current source trim. The control registers for the CTMU are: • CTMUCONH • CTMUCONL • CTMUICON REGISTER 27-1: CTMUCONH: CTMU CONTROL HIGH REGISTER R/W-0 U-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 CTMUEN — CTMUSIDL TGEN EDGEN EDGSEQEN IDISSEN CTTRIG bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7 CTMUEN: CTMU Enable bit 1 = Module is enabled 0 = Module is disabled bit 6 Unimplemented: Read as ‘0’ bit 5 CTMUSIDL: Stop in Idle Mode bit 1 = Discontinue module operation when device enters Idle mode 0 = Continue module operation in Idle mode bit 4 TGEN: Time Generation Enable bit 1 = Enables edge delay generation 0 = Disables edge delay generation bit 3 EDGEN: Edge Enable bit 1 = Edges are not blocked 0 = Edges are blocked bit 2 EDGSEQEN: Edge Sequence Enable bit 1 = Edge 1 event must occur before Edge 2 event can occur 0 = No edge sequence is needed bit 1 IDISSEN: Analog Current Source Control bit 1 = Analog current source output is grounded 0 = Analog current source output is not grounded bit 0 CTTRIG: Trigger Control bit 1 = Trigger output is enabled 0 = Trigger output is disabled DS39957B-page 406 Preliminary x = Bit is unknown 2010 Microchip Technology Inc. PIC18F87K90 FAMILY REGISTER 27-2: CTMUCONL: CTMU CONTROL LOW REGISTER R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 EDG2POL EDG2SEL1 EDG2SEL0 EDG1POL EDG1SEL1 EDG1SEL0 EDG2STAT EDG1STAT bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7 EDG2POL: Edge 2 Polarity Select bit 1 = Edge 2 is programmed for a positive edge response 0 = Edge 2 is programmed for a negative edge response bit 6-5 EDG2SEL<1:0>: Edge 2 Source Select bits 11 = CTEDG1 pin 10 = CTEDG2 pin 01 = ECCP1 Special Event Trigger 00 = ECCP2 Special Event Trigger bit 4 EDG1POL: Edge 1 Polarity Select bit 1 = Edge 1 is programmed for a positive edge response 0 = Edge 1 is programmed for a negative edge response bit 3-2 EDG1SEL<1:0>: Edge 1 Source Select bits 11 = CTEDG1 pin 10 = CTEDG2 pin 01 = ECCP1 Special Event Trigger 00 = ECCP2 Special Event Trigger bit 1 EDG2STAT: Edge 2 Status bit 1 = Edge 2 event has occurred 0 = Edge 2 event has not occurred bit 0 EDG1STAT: Edge 1 Status bit 1 = Edge 1 event has occurred 0 = Edge 1 event has not occurred 2010 Microchip Technology Inc. Preliminary x = Bit is unknown DS39957B-page 407 PIC18F87K90 FAMILY REGISTER 27-3: CTMUICON: CTMU CURRENT CONTROL REGISTER R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 ITRIM5 ITRIM4 ITRIM3 ITRIM2 ITRIM1 ITRIM0 IRNG1 IRNG0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7-2 ITRIM<5:0>: Current Source Trim bits 011111 = Maximum positive change from nominal current 011110 . . . 000001 = Minimum positive change from nominal current 000000 = Nominal current output specified by IRNG<1:0> 111111 = Minimum negative change from nominal current . . . 100010 100001 = Maximum negative change from nominal current bit 1-0 IRNG<1:0>: Current Source Range Select bits 11 = 100 x Base Current 10 = 10 x Base Current 01 = Base current level (0.55 A nominal) 00 = Current source disabled DS39957B-page 408 Preliminary x = Bit is unknown 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 27.2 CTMU Operation The CTMU works by using a fixed current source to charge a circuit. The type of circuit depends on the type of measurement being made. In the case of charge measurement, the current is fixed and the amount of time the current is applied to the circuit is fixed. The amount of voltage read by the A/D becomes a measurement of the circuit’s capacitance. In the case of time measurement, the current, as well as the capacitance of the circuit, is fixed. In this case, the voltage read by the A/D is representative of the amount of time elapsed from the time the current source starts and stops charging the circuit. If the CTMU is being used as a time delay, both capacitance and current source are fixed, as well as the voltage supplied to the comparator circuit. The delay of a signal is determined by the amount of time it takes the voltage to charge to the comparator threshold voltage. 27.2.1 THEORY OF OPERATION The operation of the CTMU is based on the equation for charge: C=I• dV dT More simply, the amount of charge measured in coulombs in a circuit is defined as current in amperes (I) multiplied by the amount of time in seconds that the current flows (t). Charge is also defined as the capacitance in farads (C) multiplied by the voltage of the circuit (V). It follows that: I•t=C•V The CTMU module provides a constant, known current source. The A/D Converter is used to measure (V) in the equation, leaving two unknowns: capacitance (C) and time (t). The above equation can be used to calculate capacitance or time, by either the relationship using the known fixed capacitance of the circuit: t = (C • V)/I or by: C = (I • t)/V using a fixed time that the current source is applied to the circuit. 27.2.2 CURRENT SOURCE At the heart of the CTMU is a precision current source, designed to provide a constant reference for measurements. The level of current is user-selectable across three ranges or a total of two orders of magnitude, with the ability to trim the output in ±2% increments (nominal). The current range is selected by the IRNG<1:0> bits (CTMUICON<1:0>), with a value of ‘00’ representing the lowest range. 2010 Microchip Technology Inc. Current trim is provided by the ITRIM<5:0> bits (CTMUICON<7:2>). These six bits allow trimming of the current source in steps of approximately 2% per step. Half of the range adjusts the current source positively and the other half reduces the current source. A value of ‘000000’ is the neutral position (no change). A value of ‘100000’ is the maximum negative adjustment (approximately -62%) and ‘011111’ is the maximum positive adjustment (approximately +62%). 27.2.3 EDGE SELECTION AND CONTROL CTMU measurements are controlled by edge events occurring on the module’s two input channels. Each channel, referred to as Edge 1 and Edge 2, can be configured to receive input pulses from one of the edge input pins (CTEDG1 and CTEDG2) or CCPx Special Event Triggers. The input channels are level-sensitive, responding to the instantaneous level on the channel rather than a transition between levels. The inputs are selected using the EDG1SEL and EDG2SEL bit pairs (CTMUCONL<3:2, 6:5>). In addition to source, each channel can be configured for event polarity using the EDGE2POL and EDGE1POL bits (CTMUCONL<7,4>). The input channels can also be filtered for an edge event sequence (Edge 1 occurring before Edge 2) by setting the EDGSEQEN bit (CTMUCONH<2>). 27.2.4 EDGE STATUS The CTMUCON register also contains two status bits, EDG2STAT and EDG1STAT (CTMUCONL<1:0>). Their primary function is to show if an edge response has occurred on the corresponding channel. The CTMU automatically sets a particular bit when an edge response is detected on its channel. The level-sensitive nature of the input channels also means that the status bits become set immediately if the channel’s configuration is changed and matches the channel’s current state. The module uses the edge status bits to control the current source output to external analog modules (such as the A/D Converter). Current is only supplied to external modules when only one (not both) of the status bits is set. Current is shut off when both bits are either set or cleared. This allows the CTMU to measure current only during the interval between edges. After both status bits are set, it is necessary to clear them before another measurement is taken. Both bits should be cleared simultaneously, if possible, to avoid re-enabling the CTMU current source. In addition to being set by the CTMU hardware, the edge status bits can also be set by software. This permits a user application to manually enable or disable the current source. Setting either (but not both) of the bits enables the current source. Setting or clearing both bits at once disables the source. Preliminary DS39957B-page 409 PIC18F87K90 FAMILY 27.2.5 INTERRUPTS The CTMU sets its interrupt flag (PIR3<3>) whenever the current source is enabled, then disabled. An interrupt is generated only if the corresponding interrupt enable bit (PIE3<3>) is also set. If edge sequencing is not enabled (i.e., Edge 1 must occur before Edge 2), it is necessary to monitor the edge status bits and determine which edge occurred last and caused the interrupt. 27.3 CTMU Module Initialization The following sequence is a general guideline used to initialize the CTMU module: 1. 2. 3. 4. Select the current source range using the IRNGx bits (CTMUICON<1:0>). Adjust the current source trim using the ITRIMx bits (CTMUICON<7:2>). Configure the edge input sources for Edge 1 and Edge 2 by setting the EDG1SEL and EDG2SEL bits (CTMUCONL<3:2> and <6:5>, respectively). Configure the input polarities for the edge inputs using the EDG1POL and EDG2POL bits (CTMUCONL<4,7>). The default configuration is for negative edge polarity (high-to-low transitions). 5. Enable edge sequencing using the EDGSEQEN bit (CTMUCONH<2>). By default, edge sequencing is disabled. 6. Select the operating mode (Measurement or Time Delay) with the TGEN bit. The default mode Measurement. 7. is Time/Capacitance Configure the module to automatically trigger an A/D conversion when the second edge event has occurred using the CTTRIG bit (CTMUCONH<0>). The conversion trigger is disabled by default. 8. 9. 10. 11. 12. 13. Discharge the connected circuit by setting the IDISSEN bit (CTMUCONH<1>). After waiting a sufficient time for the circuit to discharge, clear IDISSEN. Disable the module by clearing the CTMUEN bit (CTMUCONH<7>). Clear the Edge Status bits, EDG2STAT and EDG1STAT (CTMUCONL<1:0>). Enable both edge inputs by setting the EDGEN bit (CTMUCONH<3>). Enable the module by setting the CTMUEN bit. DS39957B-page 410 Depending on the type of measurement or pulse generation being performed, one or more additional modules may also need to be initialized and configured with the CTMU module: • Edge Source Generation: In addition to the external edge input pins, CCPx Special Event Triggers can be used as edge sources for the CTMU. • Capacitance or Time Measurement: The CTMU module uses the A/D Converter to measure the voltage across a capacitor that is connected to one of the analog input channels. • Pulse Generation: When generating system clock independent, output pulses, the CTMU module uses Comparator 2 and the associated comparator voltage reference. 27.4 Calibrating the CTMU Module The CTMU requires calibration for precise measurements of capacitance and time, as well as for accurate time delay. If the application only requires measurement of a relative change in capacitance or time, calibration is usually not necessary. An example of a lesser precision application is a capacitive touch switch, in which the touch circuit has a baseline capacitance and the added capacitance of the human body changes the overall capacitance of a circuit. If actual capacitance or time measurement is required, two hardware calibrations must take place: • The current source needs calibration to set it to a precise current. • The circuit being measured needs calibration to measure or nullify any capacitance other than that to be measured. 27.4.1 CURRENT SOURCE CALIBRATION The current source on board the CTMU module has a range of ±60% nominal for each of three current ranges. For precise measurements, it is possible to measure and adjust this current source by placing a high-precision resistor, RCAL, onto an unused analog channel. An example circuit is shown in Figure 27-2. To measure the current source: 1. 2. 3. 4. 5. 6. Preliminary Initialize the A/D Converter. Initialize the CTMU. Enable the current source by setting EDG1STAT (CTMUCONL<0>). Issue the settling time delay. Perform the A/D conversion. Calculate the current source current using I = V/RCAL, where RCAL is a high-precision resistance and V is measured by performing an A/D conversion. 2010 Microchip Technology Inc. PIC18F87K90 FAMILY The CTMU current source may be trimmed with the trim bits in CTMUICON using an iterative process to get the exact current desired. Alternatively, the nominal value without adjustment may be used. That value may be stored by software, for use in all subsequent capacitive or time measurements. To calculate the value for RCAL, the nominal current must be chosen. Then, the resistance can be calculated. For example, if the A/D Converter reference voltage is 3.3V, use 70% of full scale (or 2.31V) as the desired approximate voltage to be read by the A/D Converter. If the range of the CTMU current source is selected to be 0.55 A, the resistor value needed is calculated as, RCAL = 2.31V/0.55 A, for a value of 4.2 MΩ. Similarly, if the current source is chosen to be 5.5 A, RCAL would be 420,000Ω, and 42,000Ω if the current source is set to 55 A. FIGURE 27-2: CTMU CURRENT SOURCE CALIBRATION CIRCUIT PIC18F87K90 Current Source A value of 70% of full-scale voltage is chosen to make sure that the A/D Converter was in a range that is well above the noise floor. If an exact current is chosen to incorporate the trimming bits from CTMUICON, the resistor value of RCAL may need to be adjusted accordingly. RCAL also may be adjusted to allow for available resistor values. RCAL should be of the highest precision available, in light of the precision needed for the circuit that the CTMU will be measuring. A recommended minimum would be 0.1% tolerance. The following examples show a typical method for performing a CTMU current calibration. • Example 27-1 demonstrates how to initialize the A/D Converter and the CTMU. This routine is typical for applications using both modules. • Example 27-2 demonstrates one method for the actual calibration routine. This method manually triggers the A/D Converter to demonstrate the entire step-wise process. It is also possible to automatically trigger the conversion by setting the CTMU’s CTTRIG bit (CTMUCONH<0>). CTMU A/D Trigger A/D Converter ANx RCAL A/D MUX 2010 Microchip Technology Inc. Preliminary DS39957B-page 411 PIC18F87K90 FAMILY EXAMPLE 27-1: SETUP FOR CTMU CALIBRATION ROUTINES #include "p18cxxx.h" /**************************************************************************/ /*Setup CTMU *****************************************************************/ /**************************************************************************/ void setup(void) { //CTMUCON - CTMU Control register CTMUCONH = 0x00; //make sure CTMU is disabled CTMUCONL = 0X90; //CTMU continues to run when emulator is stopped,CTMU continues //to run in idle mode,Time Generation mode disabled, Edges are blocked //No edge sequence order, Analog current source not grounded, trigger //output disabled, Edge2 polarity = positive level, Edge2 source = //source 0, Edge1 polarity = positive level, Edge1 source = source 0, // Set Edge status bits to zero //CTMUICON - CTMU Current Control Register CTMUICON = 0x01; //0.55uA, Nominal - No Adjustment /**************************************************************************/ //Setup AD converter; /**************************************************************************/ TRISA=0x04; //set channel 2 as an input // Configured AN2 as an analog channel // ANCON0 ANCON0 = 0X04; // ANCON1 ANCON1 = 0XE0; // ADCON1 ADCON2bits.ADFM=1; ADCON2bits.ACQT=1; ADCON2bits.ADCS=2; //Resulst format 1= Right justified //Acquition time 7 = 20TAD 2 = 4TAD 1=2TAD //Clock conversion bits 6= FOSC/64 2=FOSC/32 // ADCON0 ADCON1bits.VCFG0 =0; ADCON1bits.VCFG1 =0; ADCON1bits.VNCFG =0; ADCON0bits.CHS=2; //Vref+ = AVdd //Vref+ = AVdd //Vref- = AVss //Select ADC channel ADCON0bits.ADON=1; //Turn on ADC } DS39957B-page 412 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY EXAMPLE 27-2: CURRENT CALIBRATION ROUTINE #include "p18cxxx.h" #define COUNT 500 #define DELAY for(i=0;i<COUNT;i++) #define RCAL .027 //@ 8MHz = 125uS. #define ADSCALE 1023 #define ADREF 3.3 //R value is 4200000 (4.2M) //scaled so that result is in //1/100th of uA //for unsigned conversion 10 sig bits //Vdd connected to A/D Vr+ int main(void) { int i; int j = 0; //index for loop unsigned int Vread = 0; double VTot = 0; float Vavg=0, Vcal=0, CTMUISrc = 0; //float values stored for calcs //assume CTMU and A/D have been setup correctly //see Example 25-1 for CTMU & A/D setup setup(); CTMUCONHbits.CTMUEN = 1; for(j=0;j<10;j++) { CTMUCONHbits.IDISSEN = 1; DELAY; CTMUCONHbits.IDISSEN = 0; CTMUCONLbits.EDG1STAT = 1; //Enable the CTMU //drain charge on the circuit //wait 125us //end drain of circuit DELAY; CTMUCONLbits.EDG1STAT = 0; //Begin charging the circuit //using CTMU current source //wait for 125us //Stop charging circuit PIR1bits.ADIF = 0; ADCON0bits.GO=1; while(!PIR1bits.ADIF); //make sure A/D Int not set //and begin A/D conv. //Wait for A/D convert complete Vread = ADRES; PIR1bits.ADIF = 0; VTot += Vread; //Get the value from the A/D //Clear A/D Interrupt Flag //Add the reading to the total } Vavg = (float)(VTot/10.000); Vcal = (float)(Vavg/ADSCALE*ADREF); CTMUISrc = Vcal/RCAL; //Average of 10 readings //CTMUISrc is in 1/100ths of uA } 2010 Microchip Technology Inc. Preliminary DS39957B-page 413 PIC18F87K90 FAMILY 27.4.2 CAPACITANCE CALIBRATION There is a small amount of capacitance from the internal A/D Converter sample capacitor as well as stray capacitance from the circuit board traces and pads that affect the precision of capacitance measurements. A measurement of the stray capacitance can be taken by making sure the desired capacitance to be measured has been removed. After removing the capacitance to be measured: 1. 2. 3. 4. 5. 6. Initialize the A/D Converter and the CTMU. Set EDG1STAT (= 1). Wait for a fixed delay of time, t. Clear EDG1STAT. Perform an A/D conversion. Calculate the stray and A/D sample capacitances: COFFSET = CSTRAY + CAD = (I • t)/V This measured value is then stored and used for calculations of time measurement or subtracted for capacitance measurement. For calibration, it is expected that the capacitance of CSTRAY + CAD is approximately known; CAD is approximately 4 pF. An iterative process may be required to adjust the time, t, that the circuit is charged to obtain a reasonable voltage reading from the A/D Converter. The value of t may be determined by setting COFFSET to a theoretical value and solving for t. For example, if CSTRAY is theoretically calculated to be 11 pF, and V is expected to be 70% of VDD or 2.31V, t would be: (4 pF + 11 pF) • 2.31V/0.55 A or 63 s. See Example 27-3 for a typical routine for CTMU capacitance calibration. Where: • I is known from the current source measurement step • t is a fixed delay • V is measured by performing an A/D conversion DS39957B-page 414 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY EXAMPLE 27-3: CAPACITANCE CALIBRATION ROUTINE #include "p18cxxx.h" #define #define #define #define #define #define COUNT 25 ETIME COUNT*2.5 DELAY for(i=0;i<COUNT;i++) ADSCALE 1023 ADREF 3.3 RCAL .027 //@ 8MHz INTFRC = 62.5 us. //time in uS //for unsigned conversion 10 sig bits //Vdd connected to A/D Vr+ //R value is 4200000 (4.2M) //scaled so that result is in //1/100th of uA int main(void) { int i; int j = 0; //index for loop unsigned int Vread = 0; float CTMUISrc, CTMUCap, Vavg, VTot, Vcal; //assume CTMU and A/D have been setup correctly //see Example 25-1 for CTMU & A/D setup setup(); CTMUCONHbits.CTMUEN = 1; for(j=0;j<10;j++) { CTMUCONHbits.IDISSEN = 1; DELAY; CTMUCONHbits.IDISSEN = 0; CTMUCONLbits.EDG1STAT = 1; //Enable the CTMU //drain charge on the circuit //wait 125us //end drain of circuit DELAY; CTMUCONLbits.EDG1STAT = 0; //Begin charging the circuit //using CTMU current source //wait for 125us //Stop charging circuit PIR1bits.ADIF = 0; ADCON0bits.GO=1; while(!PIR1bits.ADIF); //make sure A/D Int not set //and begin A/D conv. //Wait for A/D convert complete Vread = ADRES; PIR1bits.ADIF = 0; VTot += Vread; //Get the value from the A/D //Clear A/D Interrupt Flag //Add the reading to the total } Vavg = (float)(VTot/10.000); //Average of 10 readings Vcal = (float)(Vavg/ADSCALE*ADREF); CTMUISrc = Vcal/RCAL; //CTMUISrc is in 1/100ths of uA CTMUCap = (CTMUISrc*ETIME/Vcal)/100; } 2010 Microchip Technology Inc. Preliminary DS39957B-page 415 PIC18F87K90 FAMILY 27.5 Measuring Capacitance with the CTMU There are two ways to measure capacitance with the CTMU. The absolute method measures the actual capacitance value. The relative method only measures for any change in the capacitance. 27.5.1 ABSOLUTE CAPACITANCE MEASUREMENT For absolute capacitance measurements, both the current and capacitance calibration steps found in Section 27.4 “Calibrating the CTMU Module” should be followed. To perform these measurements: 1. 2. 3. 4. 5. 6. 7. 8. Initialize the A/D Converter. Initialize the CTMU. Set EDG1STAT. Wait for a fixed delay, T. Clear EDG1STAT. Perform an A/D conversion. Calculate the total capacitance, CTOTAL = (I * T)/V, where: • I is known from the current source measurement step (Section 27.4.1 “Current Source Calibration”) • T is a fixed delay • V is measured by performing an A/D conversion Subtract the stray and A/D capacitance (COFFSET from Section 27.4.2 “Capacitance Calibration”) from CTOTAL to determine the measured capacitance. DS39957B-page 416 27.5.2 RELATIVE CHARGE MEASUREMENT Not all applications require precise capacitance measurements. When detecting a valid press of a capacitance-based switch, only a relative change of capacitance needs to be detected. In such an application, when the switch is open (or not touched), the total capacitance is the capacitance of the combination of the board traces, the A/D Converter and other elements. A larger voltage will be measured by the A/D Converter. When the switch is closed (or touched), the total capacitance is larger due to the addition of the capacitance of the human body to the above listed capacitances and a smaller voltage will be measured by the A/D Converter. To detect capacitance changes simply: 1. 2. 3. 4. 5. Initialize the A/D Converter and the CTMU. Set EDG1STAT. Wait for a fixed delay. Clear EDG1STAT. Perform an A/D conversion. The voltage measured by performing the A/D conversion is an indication of the relative capacitance. In this case, no calibration of the current source or circuit capacitance measurement is needed. (For a sample software routine for a capacitive touch switch, see Example 27-4.) Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY EXAMPLE 27-4: ROUTINE FOR CAPACITIVE TOUCH SWITCH #include "p18cxxx.h" #define #define #define #define COUNT 500 DELAY for(i=0;i<COUNT;i++) OPENSW 1000 TRIP 300 //@ 8MHz = 125uS. //Un-pressed switch value //Difference between pressed //and un-pressed switch //amount to change //from pressed to un-pressed #define HYST 65 #define PRESSED 1 #define UNPRESSED 0 int main(void) { unsigned int Vread; unsigned int switchState; int i; //storage for reading //assume CTMU and A/D have been setup correctly //see Example 27-1 for CTMU & A/D setup setup(); CTMUCONHbits.CTMUEN = 1; //Enable the CTMU CTMUCONHbits.IDISSEN = 1; DELAY; CTMUCONHbits.IDISSEN = 0; //drain charge on the circuit //wait 125us //end drain of circuit CTMUCONLbits.EDG1STAT = 1; DELAY; CTMUCONLbits.EDG1STAT = 0; //Begin charging the circuit //using CTMU current source //wait for 125us //Stop charging circuit PIR1bits.ADIF = 0; ADCON0bits.GO=1; while(!PIR1bits.ADIF); //make sure A/D Int not set //and begin A/D conv. //Wait for A/D convert complete Vread = ADRES; //Get the value from the A/D if(Vread < OPENSW - TRIP) { switchState = PRESSED; } else if(Vread > OPENSW - TRIP + HYST) { switchState = UNPRESSED; } } 2010 Microchip Technology Inc. Preliminary DS39957B-page 417 PIC18F87K90 FAMILY 27.6 Measuring Time with the CTMU Module Time can be precisely measured after the ratio (C/I) is measured from the current and capacitance calibration step. To do that: 1. 2. 3. 4. 5. Initialize the A/D Converter and the CTMU. Set EDG1STAT. Set EDG2STAT. Perform an A/D conversion. Calculate the time between edges as T = (C/I) • V, where: • I is calculated in the current calibration step (Section 27.4.1 “Current Source Calibration”) • C is calculated in the capacitance calibration step (Section 27.4.2 “Capacitance Calibration”) • V is measured by performing the A/D conversion FIGURE 27-3: It is assumed that the time measured is small enough that the capacitance, COFFSET, provides a valid voltage to the A/D Converter. For the smallest time measurement, always set the A/D Channel Select register (AD1CHS) to an unused A/D channel, the corresponding pin for which is not connected to any circuit board trace. This minimizes added stray capacitance, keeping the total circuit capacitance close to that of the A/D Converter itself (25 pF). To measure longer time intervals, an external capacitor may be connected to an A/D channel and that channel selected whenever making a time measurement. TYPICAL CONNECTIONS AND INTERNAL CONFIGURATION FOR TIME MEASUREMENT PIC18F87K90 CTMU CTEDG1 EDG1 CTEDG2 EDG2 Current Source Output Pulse A/D Converter ANX CAD RPR DS39957B-page 418 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 27.7 Creating a Delay with the CTMU Module An example use of the external capacitor feature is interfacing with variable capacitive-based sensors, such as a humidity sensor. As the humidity varies, the pulse-width output on CTPLS will vary. An example use of the CTDIN feature is interfacing with a digital sensor. The CTPLS output pin can be connected to an input capture pin and the varying pulse width measured to determine the humidity in the application. A unique feature on board the CTMU module is its ability to generate system clock independent output pulses based on either an internal voltage or an external capacitor value. When using an external voltage, this is accomplished using the CTDIN input pin as a trigger for the pulse delay. When using an internal capacitor value, this is accomplished using the internal comparator voltage reference module and Comparator 2 input pin. The pulse is output onto the CTPLS pin. To enable this mode, set the TGEN bit. To use this feature: 1. 2. 3. See Figure 27-4 for an example circuit. When CTMUDS (ODCON3<0>) is cleared, the pulse delay is determined by the output of Comparator 2, and when it is set, the pulse delay is determined by the input of CTDIN. CDELAY is chosen by the user to determine the output pulse width on CTPLS. The pulse width is calculated by T = (CDELAY/I) * V, where I is known from the current source measurement step (Section 27.4.1 “Current Source Calibration”) and V is the internal reference voltage (CVREF). FIGURE 27-4: 4. If CTMUDS is cleared, initialize Comparator 2. If CTMUDS is cleared, initialize the comparator voltage reference. Initialize the CTMU and enable time delay generation by setting the TGEN bit. Set EDG1STAT. When CTMUDS is cleared, as soon as CDELAY charges to the value of the voltage reference trip point, an output pulse is generated on CTPLS. When CTMUDS is set, as soon as CTDIN is set, an output pulse is generated on CTPLS. TYPICAL CONNECTIONS AND INTERNAL CONFIGURATION FOR PULSE DELAY GENERATION PIC18F87K90 CTEDG1 EDG1 CTMU CTPLS Current Source Comparator CTMUI CDELAY CTMUDS CTDIN C2 CVREF C1 External Reference External Comparator 2010 Microchip Technology Inc. Preliminary DS39957B-page 419 PIC18F87K90 FAMILY 27.8 Measuring Temperature Using the CTMU Module The CTMU, along with an internal diode, can be used to measure the temperature. The ADC can be connected to the internal diode and the CTMU module can EXAMPLE 27-5: source the current to the diode. The ADC reading will reflect the temperature. With the increase, the ADC readings will go low. This can be used for low-cost temperature measurement applications. ROUTINE FOR TEMPERATURE MEASUREMENT USING INTERNAL DIODE //Initialize CTMU CTMUICON=0x03; CTMUCONHbits.CTMUEN=1; CTMUCONLbits.EDG1STAT=1; //Initialize ADC ADCON0=0xE5; ADCON1=0; ADCON2=0xBE; //ADCON and connect to Internal diode //Right justified ADCON0bits.GO=1; while(ADCON0bits.GO==1); Temp=ADRES; ;//read ADC results ( inversely proportional to temperature) ---------------------------------------------------------------------------------------------- Note: The temperature diode is not calibrated; the user will have to calibrate the diode to their application. DS39957B-page 420 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 27.9 Operation During Sleep/Idle Modes 27.9.1 SLEEP MODE When the device enters any Sleep mode, the CTMU module current source is always disabled. If the CTMU is performing an operation that depends on the current source when Sleep mode is invoked, the operation may not terminate correctly. Capacitance and time measurements may return erroneous values. 27.9.2 IDLE MODE The behavior of the CTMU in Idle mode is determined by the CTMUSIDL bit (CTMUCONH<5>). If CTMUSIDL is cleared, the module will continue to operate in Idle mode. If CTMUSIDL is set, the module’s current source is disabled when the device enters Idle mode. If the TABLE 27-1: Name module is performing an operation when Idle mode is invoked, in this case, the results will be similar to those with Sleep mode. 27.10 Effects of a Reset on CTMU Upon Reset, all registers of the CTMU are cleared. This disables the CTMU module, turns off its current source and returns all configuration options to their default settings. The module needs to be re-initialized following any Reset. If the CTMU is in the process of taking a measurement at the time of Reset, the measurement will be lost. A partial charge may exist on the circuit that was being measured, which should be properly discharged before the CTMU makes subsequent attempts to make a measurement. The circuit is discharged by setting and clearing the IDISSEN bit (CTMUCONH<1>) while the A/D Converter is connected to the appropriate channel. REGISTERS ASSOCIATED WITH CTMU MODULE Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 EDGSEQEN IDISSEN CTTRIG CTMUCONH CTMUEN — CTMUSIDL TGEN EDGEN CTMUCONL EDG2POL EDG2SEL1 EDG2SEL0 EDG1POL EDG1SEL1 CTMUICON ITRIM5 ITRIM4 ITRIM3 ITRIM2 ITRIM1 EDG1SEL0 EDG2STAT EDG1STAT ITRIM0 IRNG1 IRNG0 Reset Values on Page: 78 78 78 PIR3 TMR5GIF LCDIF RC2IF TX2IF CTMUIF CCP2IF CCP1IF RTCCIF 75 PIE3 TMR5GIE LCDIE RC2IE TX2IE CTMUIE CCP2IE CCP1IE RTCCIE 75 TMR5GIP LCDIP RC2IP TX2IP CTMUIP CCP2IP CCP1IP RTCCIP 75 IPR3 Legend: — = unimplemented, read as ‘0’ 2010 Microchip Technology Inc. Preliminary DS39957B-page 421 PIC18F87K90 FAMILY NOTES: DS39957B-page 422 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 28.0 SPECIAL FEATURES OF THE CPU The PIC18F87K90 family of devices includes several features intended to maximize reliability and minimize cost through elimination of external components. These include: • Oscillator Selection • Resets: - Power-on Reset (POR) - Power-up Timer (PWRT) - Oscillator Start-up Timer (OST) - Brown-out Reset (BOR) • Interrupts • Watchdog Timer (WDT) and On-Chip Regulator • Fail-Safe Clock Monitor • Two-Speed Start-up • Code Protection • ID Locations • In-Circuit Serial Programming™ The oscillator can be configured for the application depending on frequency, power, accuracy and cost. All of the options are discussed in detail in Section 3.0 “Oscillator Configurations”. 28.1 Configuration Bits The Configuration bits can be programmed (read as ‘0’) or left unprogrammed (read as ‘1’) to select various device configurations. These bits are mapped starting at program memory location, 300000h. The user will note that address, 300000h, is beyond the user program memory space. In fact, it belongs to the configuration memory space (300000h-3FFFFFh), which can only be accessed using table reads and table writes. Software programming the Configuration registers is done in a manner similar to programming the Flash memory. The WR bit in the EECON1 register starts a self-timed write to the Configuration register. In normal operation mode, a TBLWT instruction with the TBLPTR pointing to the Configuration register sets up the address and the data for the Configuration register write. Setting the WR bit starts a long write to the Configuration register. The Configuration registers are written a byte at a time. To write or erase a configuration cell, a TBLWT instruction can write a ‘1’ or a ‘0’ into the cell. For additional details on Flash programming, refer to Section 7.5 “Writing to Flash Program Memory”. A complete discussion of device Resets and interrupts is available in previous sections of this data sheet. In addition to their Power-up and Oscillator Start-up Timers provided for Resets, the PIC18F87K90 family of devices has a Watchdog Timer, which is either permanently enabled via the Configuration bits or software controlled (if configured as disabled). The inclusion of an internal RC (LF-INTOSC) oscillator also provides the additional benefits of a Fail-Safe Clock Monitor (FSCM) and Two-Speed Start-up. FSCM provides for background monitoring of the peripheral clock and automatic switchover in the event of its failure. Two-Speed Start-up enables code to be executed almost immediately on start-up, while the primary clock source completes its start-up delays. All of these features are enabled and configured by setting the appropriate Configuration register bits. 2010 Microchip Technology Inc. Preliminary DS39957B-page 423 PIC18F87K90 FAMILY TABLE 28-1: CONFIGURATION BITS AND DEVICE IDs File Name Bit 7 Bit 6 Bit 5 300000h CONFIG1L — XINST — 300001h CONFIG1H IESO FCMEN — 300002h CONFIG2L — 300003h CONFIG2H — WDTPS4 300004h CONFIG3L — 300005h CONFIG3H MCLRE 300006h CONFIG4L Bit 4 Bit 3 Bit 2 SOSCSEL1 SOSCSEL0 INTOSCSEL Bit 1 Bit 0 Default/ Unprogrammed Value — RETEN -1-1 1--1 PLLCFG FOSC3 FOSC2 FOSC1 FOSC0 0000 1000 BORV1 BORV0 BOREN1 BOREN0 PWRTEN -111 1111 WDTPS3 WDTPS2 WDTPS1 WDTPS0 WDTEN1 WDTEN0 -111 1111 — — — — — — RTCOSC ---- ---1 — — — MSSPMSK — ECCPMX(2) CCP2MX 1--- 1-11 DEBUG — — BBSIZ0 — — — STVREN 1--1 ---1 300008h CONFIG5L CP7(1) CP6(1) CP5(1) CP4(1) CP3 CP2 CP1 CP0 1111 1111 300009h CONFIG5H CPD CPB — — — — — — 11-- ---- 30000Ah CONFIG6L WRT7(1) WRT6(1) WRT5(1) WRT4(1) WRT3 WRT2 WRT1 WRT0 1111 1111 30000Bh CONFIG6H WRTD WRTB WRTC — — — — — 111- ---- BORPWR1 BORWPR0 (1) 30000Ch CONFIG7L EBTR7 (1) EBTR3 EBTR2 EBTR1 EBTR0 1111 1111 — EBTRB — — — — — — -1-- ---- 3FFFFEh DEVID1(3) DEV2 DEV1 DEV0 REV4 REV3 REV2 REV1 REV0 xxxx xxxx 3FFFFFh DEVID2(3) DEV10 DEV9 DEV8 DEV7 DEV6 DEV5 DEV4 DEV3 xxxx xxxx Note 1: 2: 3: EBTR5 (1) 30000Dh CONFIG7H Legend: EBTR6 (1) EBTR4 x = unknown, u = unchanged, - = unimplemented, q = value depends on condition. Shaded cells are unimplemented, read as ‘0’. Implemented in the PIC18F67K90 and PIC18F87K90 devices. Implemented in the 80-pin devices (PIC18F8XK90). See Register 28-14 for DEVID1 values. DEVID registers are read-only and cannot be programmed by the user. DS39957B-page 424 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY REGISTER 28-1: CONFIG1L: CONFIGURATION REGISTER 1 LOW (BYTE ADDRESS 300000h) U-0 R/P-1 U-0 — XINST — R/P-1 R/P-1 R/P-1 U-0 R/P-1 — RETEN SOSCSEL1 SOSCSEL0 INTOSCSEL0 bit 7 bit 0 Legend: P = Programmable bit R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 Unimplemented: Read as ‘0’ bit 6 XINST: Extended Instruction Set Enable bit 1 = Instruction set extension and Indexed Addressing mode are enabled 0 = Instruction set extension and Indexed Addressing mode are disabled (Legacy mode) bit 5 Unimplemented: Read as ‘0’ bit 4-3 SOSCSEL<1:0>: SOSC Power Selection and Mode Configuration bits 11 = High-power SOSC circuit is selected 10 = Digital (SCLKI) mode: I/O port functionality of RC0 and RC1 is enabled 01 = Low-power SOSC circuit is selected 00 = Reserved bit 2 INTOSCSEL: LF-INTOSC Low-Power Enable bit 1 = LF-INTOSC is in High-Power mode during Sleep 0 = LF-INTOSC is in Low-Power mode during Sleep bit 1 Unimplemented: Read as ‘0’ bit 0 RETEN: VREG Sleep Enable bit 1 = Regulator power is in Sleep mode, controlled by VREGSLP (WDTCON<7>) 0 = Regulator power is in Sleep mode, controlled by SRETEN (WDTCON<4>). Ultra low-power regulator is enabled. 2010 Microchip Technology Inc. Preliminary DS39957B-page 425 PIC18F87K90 FAMILY REGISTER 28-2: CONFIG1H: CONFIGURATION REGISTER 1 HIGH (BYTE ADDRESS 300001h) R/P-0 R/P-0 U-0 U-0 R/P-1 R/P-0 R/P-0 R/P-0 IESO FCMEN — PLLCFG(1) FOSC3(2) FOSC2(2) FOSC1(2) FOSC0(2) bit 7 bit 0 Legend: P = Programmable bit R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 IESO: Internal/External Oscillator Switchover bit 1 = Two-Speed Start-up is enabled 0 = Two-Speed Start-up is disabled bit 6 FCMEN: Fail-Safe Clock Monitor Enable bit 1 = Fail-Safe Clock Monitor is enabled 0 = Fail-Safe Clock Monitor is disabled bit 5 Unimplemented: Read as ‘0’ bit 4 PLLCFG: 4x PLL Enable bit(1) 1 = Oscillator is multiplied by 4 0 = Oscillator is used directly bit 3-0 FOSC<3:0>: Oscillator Selection bits(2) 1101 = EC1, EC oscillator (low power, DC-160 kHz) 1100 = EC1IO, EC oscillator with CLKOUT function on RA6 (low power, DC-160 kHz) 1011 = EC2, EC oscillator (medium power, 160 kHz-4 MHz) 1010 = EC2IO, EC oscillator with CLKOUT function on RA6 (medium power, DC-160 kHz) 0101 = EC3, EC oscillator (high power, 4 MHz-64 MHz) 0100 = EC3IO, EC oscillator with CLKOUT function on RA6 (high power, 4 MHz-64 MHz) 0011 = HS1, HS oscillator (medium power, 4 MHz-16 MHz) 0010 = HS2, HS oscillator (high power, 16 MHz-25 MHz) 0001 = XT oscillator 0000 = LP oscillator 0111 = RC, External RC oscillator 0110 = RCIO, External RC oscillator with CKLOUT function on RA6 1000 = INTIO2, Internal RC oscillator 1001 = INTIO1, Internal RC oscillator with CLKOUT function on RA6 Note 1: 2: Not valid for the INTIOx PLL mode. INTIO+PLL can only be enabled by the PLLEN bit (OSCTUNE<6>). Other PLL modes can be enabled by either the PLLEN bit or the PLLCFG (CONFIG1H<4>) bit. DS39957B-page 426 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY REGISTER 28-3: U-0 — CONFIG2L: CONFIGURATION REGISTER 2 LOW (BYTE ADDRESS 300002h) R/P-1 R/P-1 (1) BORPWR1 R/P-1 (1) BORPWR0 BORV1 R/P-1 (1) BORV0 (1) R/P-1 R/P-1 (2) BOREN1 BOREN0 R/P-1 (2) PWRTEN(2) bit 7 bit 0 Legend: P = Programmable bit R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 Unimplemented: Read as ‘0’ bit 6-5 BORPWR<1:0>: BORMV Power Level bits(1) 11 = ZPBORVMV instead of BORMV is selected 10 = BORMV is set to high-power level 01 = BORMV is set to medium-power level 00 = BORMV is set to low-power level bit 4-3 BORV<1:0>: Brown-out Reset Voltage bits(1) 11 = VBORMV is set to 1.8V 10 = VBORMV is set to 2.0V 01 = VBORMV is set to 2.7V 00 = VBORMV is set to 3.0V bit 2-1 BOREN<1:0>: Brown-out Reset Enable bits(2) 11 = Brown-out Reset is enabled in hardware only (SBOREN is disabled) 10 = Brown-out Reset is enabled in hardware only and disabled in Sleep mode (SBOREN is disabled) 01 = Brown-out Reset is enabled and controlled by software (SBOREN is enabled) 00 = Brown-out Reset is disabled in hardware and software bit 0 PWRTEN: Power-up Timer Enable bit(2) 1 = PWRT is disabled 0 = PWRT is enabled Note 1: 2: For the specifications, see Section 31.1 “DC Characteristics: Supply Voltage PIC18F87K90 Family (Industrial)”. The Power-up Timer is decoupled from Brown-out Reset, allowing these features to be independently controlled. 2010 Microchip Technology Inc. Preliminary DS39957B-page 427 PIC18F87K90 FAMILY REGISTER 28-4: CONFIG2H: CONFIGURATION REGISTER 2 HIGH (BYTE ADDRESS 300003h) U-0 R/P-1 R/P-1 R/P-1 R/P-1 R/P-1 R/P-1 R/P-1 — WDTPS4 WDTPS3 WDTPS2 WDTPS1 WDTPS0 WDTEN1 WDTEN0 bit 7 bit 0 Legend: P = Programmable bit R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 Unimplemented: Read as ‘0’ bit 6-2 WDTPS<4:0>: Watchdog Timer Postscale Select bits 11111 = 1:1,048,576 10011 = 1:524,288 10010 = 1:262,144 10001 = 1:131,072 10000 = 1:65,536 01111 = 1:32,768 01110 = 1:16,384 01101 = 1:8,192 01100 = 1:4,096 01011 = 1:2,048 01010 = 1:1,024 01001 = 1:512 01000 = 1:256 00111 = 1:128 00110 = 1:64 00101 = 1:32 00100 = 1:16 00011 = 1:8 00010 = 1:4 00001 = 1:2 00000 = 1:1 bit 1-0 WDTEN<1:0>: Watchdog Timer Enable bits 11 = WDT is enabled in hardware; SWDTEN bit is disabled 10 = WDT is controlled by the SWDTEN bit setting 01 = WDT is enabled only while device is active and is disabled in Sleep mode; SWDTEN bit is disabled 00 = WDT is disabled in hardware; SWDTEN bit is disabled DS39957B-page 428 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY REGISTER 28-5: CONFIG3L: CONFIGURATION REGISTER 3 LOW (BYTE ADDRESS 300004h) U-0 U-0 U-0 U-0 U-0 U-0 U-0 R/P-1 — — — — — — — RTCOSC bit 7 bit 0 Legend: P = Programmable bit R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7-1 Unimplemented: Read as ‘0’ bit 0 RTCOSC: RTCC Reference Clock Select bit 1 = RTCC uses SOSC as a reference clock 0 = RTCC uses LF-INTOSC as a reference clock REGISTER 28-6: R/P-1 CONFIG3H: CONFIGURATION REGISTER 3 HIGH (BYTE ADDRESS 300005h) U-0 U-0 — MCLRE x = Bit is unknown — U-0 R/P-1 — MSSPMSK U-0 R/P-1 R/P-1 — ECCPMX(1) CCP2MX bit 7 bit 0 Legend: P = Programmable bit R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7 MCLRE: MCLR Pin Enable bit 1 = MCLR pin is enabled; RG5 input pin is disabled 0 = RG5 input pin is enabled; MCLR is disabled x = Bit is unknown bit 6-4 Unimplemented: Read as ‘0’ bit 3 MSSPMSK: MSSP V3 7-Bit Address Masking Mode Enable bit 1 = 7-Bit Address Masking mode is enabled 0 = 5-Bit Address Masking mode is enabled bit 2 Unimplemented: Read as ‘0’ bit 1 ECCPMX: ECCP MUX bit(1) 1 = Enhanced ECCP1 (P1B/P1C) is multiplexed onto RE6 and RE5, CCP6 onto RE6, and CCP7 onto RE5 Enhanced ECCP3 (P3B/P3C) is multiplexed onto RE4 and RE3, CCP6 onto RE4, and CCP7 onto RE3 0 = Enhanced ECCP1 (P1B/P1C) is multiplexed onto RH7 and RH6, CCP8 onto RH7, and CCP9 onto RH6 Enhanced ECCP3 (P3B/P3C) is multiplexed onto RH5 and RH4, CCP8 onto RH5, and CCP9 onto RH4 bit 0 CCP2MX: ECCP2 MUX bit 1 = ECCP2 is multiplexed with RC1 0 = ECCP2 input/output is multiplexed with RE7(1) Note 1: This feature is only available on 80-pin devices. 2010 Microchip Technology Inc. Preliminary DS39957B-page 429 PIC18F87K90 FAMILY REGISTER 28-7: CONFIG4L: CONFIGURATION REGISTER 4 LOW (BYTE ADDRESS 300006h) R/P-1 U-0 U-0 R/P-0 U-0 R/P-0 U-0 R/P-1 DEBUG — — BBSIZ0 — — — STVREN bit 7 bit 0 Legend: P = Programmable bit R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 DEBUG: Background Debugger Enable bit 1 = Background debugger is disabled, RB6 and RB7 are configured as general purpose I/O pins 0 = Background debugger is enabled, RB6 and RB7 are dedicated to In-Circuit Debug bit 6-5 Unimplemented: Read as ‘0’ bit 4 BBSIZ<0>: Boot Block Size Select bit 1 = 2 kW boot block size 0 = 1 kW boot block size bit 3-1 Unimplemented: Read as ‘0’ bit 0 STVREN: Stack Full/Underflow Reset Enable bit 1 = Stack full/underflow will cause a Reset 0 = Stack full/underflow will not cause a Reset DS39957B-page 430 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY REGISTER 28-8: CONFIG5L: CONFIGURATION REGISTER 5 LOW (BYTE ADDRESS 300008h)(2) R/C-1 R/C-1 R/C-1 R/C-1 R/C-1 R/C-1 R/C-1 R/C-1 CP7(1) CP6(1) CP5(1) CP4(1) CP3 CP2 CP1 CP0 bit 7 bit 0 Legend: C = Clearable bit R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7 CP7: Code Protection bit(1) 1 = Block 7 is not code-protected 0 = Block 7 is code-protected bit 6 CP6: Code Protection bit(1) 1 = Block 6 is not code-protected 0 = Block 6 is code-protected bit 5 CP5: Code Protection bit(1) 1 = Block 5 is not code-protected 0 = Block 5 is code-protected bit 4 CP4: Code Protection bit(1) 1 = Block 4 is not code-protected 0 = Block 4 is code-protected bit 3 CP3: Code Protection bit 1 = Block 3 is not code-protected 0 = Block 3 is code-protected bit 2 CP2: Code Protection bit 1 = Block 2 is not code-protected 0 = Block 2 is code-protected bit 1 CP1: Code Protection bit 1 = Block 1 is not code-protected 0 = Block 1 is code-protected bit 0 CP0: Code Protection bit 1 = Block 0 is not code-protected 0 = Block 0 is code-protected Note 1: 2: x = Bit is unknown This bit is only available on PIC18F67K90 and PIC18F87K90. For the memory size of the blocks, refer to Figure 28-6. 2010 Microchip Technology Inc. Preliminary DS39957B-page 431 PIC18F87K90 FAMILY REGISTER 28-9: CONFIG5H: CONFIGURATION REGISTER 5 HIGH (BYTE ADDRESS 300009h)(1) R/C-1 R/C-1 U-0 U-0 U-0 U-0 U-0 U-0 CPD CPB — — — — — — bit 7 bit 0 Legend: C = Clearable bit R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7 CPD: Data EEPROM Code Protection bit 1 = Data EEPROM is not code-protected 0 = Data EEPROM is code-protected bit 6 CPB: Boot Block Code Protection bit 1 = Boot block is not code-protected 0 = Boot block is code-protected bit 5-0 Unimplemented: Read as ‘0’ Note 1: x = Bit is unknown For the memory size of the blocks, refer to Figure 28-6. DS39957B-page 432 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY REGISTER 28-10: CONFIG6L: CONFIGURATION REGISTER 6 LOW (BYTE ADDRESS 30000Ah)(2) R/C-1 R/C-1 R/C-1 R/C-1 R/C-1 R/C-1 R/C-1 R/C-1 WRT7(1) WRT6(1) WRT5(1) WRT4(1) WRT3 WRT2 WRT1 WRT0 bit 7 bit 0 Legend: C = Clearable bit R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7 WRT7: Write Protection bit(1) 1 = Block 7 is not write-protected 0 = Block 7 is write-protected bit 6 WRT6: Write Protection bit(1) 1 = Block 6 is not write-protected 0 = Block 6 is write-protected bit 5 WRT5: Write Protection bit(1) 1 = Block 5 is not write-protected 0 = Block 5 is write-protected bit 4 WRT4: Write Protection bit(1) 1 = Block 4 is not write-protected 0 = Block 4 is write-protected bit 3 WRT3: Write Protection bit 1 = Block 3 is not write-protected 0 = Block 3 is write-protected bit 2 WRT2: Write Protection bit 1 = Block 2 is not write-protected 0 = Block 2 is write-protected bit 1 WRT1: Write Protection bit 1 = Block 1 is not write-protected 0 = Block 1 is write-protected bit 0 WRT0: Write Protection bit 1 = Block 0 is not write-protected 0 = Block 0 is write-protected Note 1: 2: x = Bit is unknown This bit is only available on PIC18F67K90 and PIC18F87K90. For the memory size of the blocks, refer to Figure 28-6. 2010 Microchip Technology Inc. Preliminary DS39957B-page 433 PIC18F87K90 FAMILY REGISTER 28-11: CONFIG6H: CONFIGURATION REGISTER 6 HIGH (BYTE ADDRESS 30000Bh)(2) R/C-1 R/C-1 R-1 U-0 U-0 U-0 U-0 U-0 WRTD WRTB WRTC(1) — — — — — bit 7 bit 0 Legend: C = Clearable bit R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7 WRTD: Data EEPROM Write Protection bit 1 = Data EEPROM is not write-protected 0 = Data EEPROM is write-protected bit 6 WRTB: Boot Block Write Protection bit 1 = Boot block is not write-protected 0 = Boot block is write-protected bit 5 WRTC: Configuration Register Write Protection bit(1) 1 = Configuration registers are not write-protected 0 = Configuration registers are write-protected bit 4-0 Unimplemented: Read as ‘0’ Note 1: 2: x = Bit is unknown This bit is read-only in normal execution mode; it can be written only in Program mode. For the memory size of the blocks, refer to Figure 28-6. DS39957B-page 434 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY REGISTER 28-12: CONFIG7L: CONFIGURATION REGISTER 7 LOW (BYTE ADDRESS 30000Ch)(3) R/C-1 R/C-1 R/C-1 R/C-1 R/C-1 R/C-1 R/C-1 R/C-1 EBTR7(1) EBTR6(1) EBTR5(1) EBTR4(1) EBTR3 EBTR2 EBTR1 EBTR0 bit 7 bit 0 Legend: C = Clearable bit R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7 EBTR7: Table Read Protection bit(1) 1 = Block 7 is not protected from table reads executed in other blocks 0 = Block 7 is protected from table reads executed in other blocks bit 6 EBTR6: Table Read Protection bit(1) 1 = Block 6 is not protected from table reads executed in other blocks 0 = Block 6 is protected from table reads executed in other blocks bit 5 EBTR5: Table Read Protection bit(1) 1 = Block 5 is not protected from table reads executed in other blocks 0 = Block 5 is protected from table reads executed in other blocks bit 4 EBTR4: Table Read Protection bit(1) 1 = Block 4 is not protected from table reads executed in other blocks 0 = Block 4 is protected from table reads executed in other blocks bit 3 EBTR3: Table Read Protection bit 1 = Block 3 is not protected from table reads executed in other blocks 0 = Block 3 is protected from table reads executed in other blocks bit 2 EBTR2: Table Read Protection bit 1 = Block 2 is not protected from table reads executed in other blocks 0 = Block 2 is protected from table reads executed in other blocks bit 1 EBTR1: Table Read Protection bit 1 = Block 1 is not protected from table reads executed in other blocks 0 = Block 1 is protected from table reads executed in other blocks bit 0 EBTR0: Table Read Protection bit 1 = Block 0 is not protected from table reads executed in other blocks 0 = Block 0 is protected from table reads executed in other blocks Note 1: 2: 3: x = Bit is unknown This bit is only available on PIC18F67K90 and PIC18F87K90. This bit is only available on PIC18F66K90, PIC18F67K90, PIC18F86K90 and PIC18F87K90. For the memory size of the blocks, refer to Figure 28-6. 2010 Microchip Technology Inc. Preliminary DS39957B-page 435 PIC18F87K90 FAMILY REGISTER 28-13: CONFIG7H: CONFIGURATION REGISTER 7 HIGH (BYTE ADDRESS 30000Dh)(1) U-0 R/C-1 U-0 U-0 U-0 U-0 U-0 U-0 — EBTRB — — — — — — bit 7 bit 0 Legend: C = Clearable bit R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 Unimplemented: Read as ‘0’ bit 6 EBTRB: Boot Block Table Read Protection bit 1 = Boot block is not protected from table reads executed in other blocks 0 = Boot block is protected from table reads executed in other blocks bit 5-0 Unimplemented: Read as ‘0’ Note 1: For the memory size of the blocks, refer to Figure 28-6. DS39957B-page 436 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY REGISTER 28-14: DEVID1: DEVICE ID REGISTER 1 FOR THE PIC18F87K90 FAMILY R R R R R R R R DEV2 DEV1 DEV0 REV4 REV3 REV2 REV1 REV0 bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7-5 DEV<2:0>: Device ID bits Devices with DEV<10:3> of 0101 0010 (see DEVID2): 010 = PIC18F65K90 000 = PIC18F66K90 101 = PIC18F85K90 011 = PIC18F86K90 Devices with DEV<10:3> of 0101 0001: 000 = PIC18F67K90 010 = PIC18F87K90 bit 4-0 REV<4:0>: Revision ID bits These bits are used to indicate the device revision. x = Bit is unknown REGISTER 28-15: DEVID2: DEVICE ID REGISTER 2 FOR THE PIC18F87K90 FAMILY R R R R R R R R DEV10(1) DEV9(1) DEV8(1) DEV7(1) DEV6(1) DEV5(1) DEV4(1) DEV3(1) bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared bit 7-0 Note 1: x = Bit is unknown DEV<10:3>: Device ID bits(1) These bits are used with the DEV<2:0> bits in the Device ID Register 1 to identify the part number. 0101 0010 = PIC18F65K90, PIC18F66K90, PIC18F85K90 and PIC18F86K90 0101 0001 = PIC18F67K90 and PIC18F87K90 These values for DEV<10:3> may be shared with other devices. The specific device is always identified by using the entire DEV<10:0> bit sequence. 2010 Microchip Technology Inc. Preliminary DS39957B-page 437 PIC18F87K90 FAMILY 28.2 Watchdog Timer (WDT) For the PIC18F87K90 family of devices, the WDT is driven by the LF-INTOSC source. When the WDT is enabled, the clock source is also enabled. The nominal WDT period is 4 ms and has the same stability as the LF-INTOSC oscillator. The 4 ms period of the WDT is multiplied by a 16-bit postscaler. Any output of the WDT postscaler is selected by a multiplexer, controlled by bits in Configuration Register 2H. Available periods range from 4 ms to 4,194 seconds (about one hour). The WDT and postscaler are cleared when any of the following events occur: a SLEEP or CLRWDT instruction is executed, the IRCF bits (OSCCON<6:4>) are changed or a clock failure has occurred. The WDT can be operated in one of four modes as determined by CONFIG2H (WDTEN<1:0>) The four modes are: • WDT Enabled • WDT Disabled • WDT under software control (WDTCON<0>, SWDTEN) • WDT - Enabled during normal operation - Disabled during Sleep Note 1: The CLRWDT and SLEEP instructions clear the WDT and postscaler counts when executed. 2: Changing the setting of the IRCF bits (OSCCON<6:4>) clears the WDT and postscaler counts. 3: When a CLRWDT instruction is executed, the postscaler count will be cleared. FIGURE 28-1: WDT BLOCK DIAGRAM WDT Enabled, SWDTEN Disabled WDT Controlled with SWDTEN bit Setting WDT Enabled only While Device Active, Disabled WDT Disabled in Hardware, SWDTEN Disabled Enable WDT WDTEN1 WDTEN0 WDT Counter INTRC Source Wake-up from Power-Managed Modes 128 Change on IRCF<2:0> bits Programmable Postscaler Reset 1:1 to 1:1,048,576 CLRWDT WDT Reset All Device Resets WDTPS<3:0> 4 Sleep SWDTEN WDTEN<1:0> Enable WDT INTRC Source DS39957B-page 438 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 28.2.1 CONTROL REGISTER Register 28-16 shows the WDTCON register. This is a readable and writable register which contains a control bit that allows software to override the WDT Enable Configuration bit, but only if the Configuration bit has disabled the WDT. REGISTER 28-16: WDTCON: WATCHDOG TIMER CONTROL REGISTER R/W-0 U-0 R-x R/W-0 U-0 R/W-0 R/W-0 R/W-0 REGSLP — ULPLVL(3) SRETEN(2) — ULPEN ULPSINK(3) SWDTEN(1) bit 7 bit 0 Legend: R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’ -n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown bit 7 REGSLP: Regulator Voltage Sleep Enable bit 1 = Regulator goes into Low-Power mode when device’s Sleep mode is enabled 0 = Regulator stays in normal mode when device’s Sleep mode is activated bit 6 Unimplemented: Read as ‘0’ bit 5 ULPLVL: Ultra Low-Power Wake-up Output bit(3) 1 = Voltage on RA0 > ~0.5V 0 = Voltage on RA0 < ~0.5V bit 4 SRETEN: Regulator Voltage Sleep Disable bit(2) 1 = If RETEN (CONFIG1L<0>) = 0 and the regulator is enabled, the device goes into Ultra Low-Power mode in Sleep 0 = The regulator is on when device’s Sleep mode is enabled and the Low-Power mode is controlled by REGSLP bit 3 Unimplemented: Read as ‘0’ bit 2 ULPEN: Ultra Low-Power Wake-up Module Enable bit 1 = Ultra low-power wake-up module is enabled; ULPLVL bit indicates comparator output 0 = Ultra low-power wake-up module is disabled bit 1 ULPSINK: Ultra Low-Power Wake-up Current Sink Enable bit(3) 1 = Ultra low-power wake-up current sink is enabled 0 = Ultra low power wake-up current sink is disabled bit 0 SWDTEN: Software Controlled Watchdog Timer Enable bit(1) 1 = Watchdog Timer is on 0 = Watchdog Timer is off Note 1: 2: 3: This bit has no effect if the Configuration bits, WDTEN<1:0>, are enabled. This bit is available only when ENVREG = 1 and RETEN = 0. Not valid unless ULPEN = 1. TABLE 28-2: Name RCON WDTCON SUMMARY OF WATCHDOG TIMER REGISTERS Bit 7 Bit 6 IPEN SBOREN REGSLP — Bit 5 Bit 4 Bit 3 Bit 2 CM RI TO PD ULPLVL SRETEN — ULPEN Bit 1 Bit 0 POR BOR ULPSINK SWDTEN Reset Values on Page: 74 74 Legend: — = unimplemented, read as ‘0’. Shaded cells are not used by the Watchdog Timer. 2010 Microchip Technology Inc. Preliminary DS39957B-page 439 PIC18F87K90 FAMILY 28.3 On-Chip Voltage Regulator FIGURE 28-2: All of the PIC18F87K90 family devices power their core digital logic at a nominal 3.3V. For designs that are required to operate at a higher typical voltage, such as 5V, all family devices incorporate two on-chip regulators that allows the device to run its core logic from VDD. Those regulators are: CONNECTIONS FOR THE ON-CHIP REGULATOR Regulator Enabled (ENVREG tied to VDD): 5V PIC18F87K90 VDD ENVREG • Normal On-Chip Regulator • Ultra Low-Power, On-Chip Regulator VDDCORE/VCAP CF The hardware configuration of these regulators are the same and are explained in Section 28.3.1. The regulators’ only differences relate to when the device enters Sleep, as explained in Section 28.3.2. 28.3.1 VSS Regulator Disabled (ENVREG tied to VSS): REGULATOR ENABLE/DISABLE BY HARDWARE 3.3V(1) The regulator can be enabled or disabled only by hardware. The regulator is controlled by the ENVREG pin and the VDDCORE/VCAP pin. 28.3.1.1 PIC18F87K90 VDD ENVREG Regulator Enable Mode VDDCORE/VCAP Tying VDD to the pin enables the regulator, which in turn, provides power to the core from the other VDD pins. When the regulator is enabled, a low-ESR filter capacitor must be connected to the VDDCORE/VCAP pin (see Figure 28-2). This helps maintain the regulator’s stability. The recommended value for the filter capacitor is given in Section 31.2 DC Characteristics. 28.3.1.2 0.1 F VSS Note 1: These are typical operating voltages. For the full operating ranges of VDD and VDDCORE, see Section 31.2 DC Characteristics. Regulator Disable Mode If ENVREG is tied to VSS, the regulator is disabled. In this case, a 0.1 F capacitor should be connected to the VDDCORE/VCAP pin (see Figure 28-2). When the regulator is being used, the overall voltage budget is very tight. The regulator should operate the device down to 1.8V. When VDD drops below 3.3V, the regulator no longer regulates, but the output voltage follows the input until VDD reaches 1.8V. Below this voltage, the output of the regulator output may drop to 0V. DS39957B-page 440 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 28.3.2 OPERATION OF REGULATOR IN SLEEP The various modes of regulator operation are shown in Table 28-3. The difference in the two regulators’ operation arises with Sleep mode. The ultra low-power regulator gives the device the lowest current in the Regulator Enabled mode. The on-chip regulator can go into a lower power mode when the device goes to Sleep by setting the REGSLP bit (WDTCON<7>). This puts the regulator in a standby mode so that the device consumes much less current. The on-chip regulator can also go into the Ultra LowPower mode, which consumes the lowest current possible with the regulator enabled. This mode is controlled by the RETEN bit (CONFIG1L<0>) and SRETEN bit (WDTCON<4>). TABLE 28-3: When the ultra low-power regulator is in Sleep mode, the internal reference voltages in the chip will be shut off and any interrupts referring to the internal reference will not wake up the device. If the BOR or LVD is enabled, the regulator will keep the internal references on and the lowest possible current will not be achieved. When using the ultra low-power regulator in Sleep mode, the device will take about 250 s, typical, to start executing the code after it wakes up. SLEEP MODE REGULATOR SETTINGS(1) Regulator Power Mode VREGSLP WDTCON<7> SRETEN WDTCON<4> RETEN CONFIG1L<0> Enabled Normal Operation (Sleep) 0 x 1 Enabled Low-Power mode (Sleep) 1 x 1 Enabled Normal Operation (Sleep) 0 0 x Enabled Low-Power mode (Sleep) 1 0 x Enabled Ultra Low-Power mode (Sleep) x 1 0 Note 1: x = Indicates that VIT status is invalid. 2010 Microchip Technology Inc. Preliminary DS39957B-page 441 PIC18F87K90 FAMILY 28.4 Two-Speed Start-up In all other power-managed modes, Two-Speed Startup is not used. The device will be clocked by the currently selected clock source until the primary clock source becomes available. The setting of the IESO bit is ignored. The Two-Speed Start-up feature helps to minimize the latency period from oscillator start-up to code execution by allowing the microcontroller to use the INTOSC (LF-INTOSC, MF-INTOSC, HF-INTOSC) oscillator as a clock source until the primary clock source is available. It is enabled by setting the IESO Configuration bit. 28.4.1 Two-Speed Start-up should be enabled only if the primary oscillator mode is LP, XT or HS (Crystal-Based modes). Other sources do not require an OST start-up delay; for these, Two-Speed Start-up should be disabled. While using the INTOSC oscillator in Two-Speed Startup, the device still obeys the normal command sequences for entering power-managed modes, including multiple SLEEP instructions (refer to Section 4.1.4 “Multiple Sleep Commands”). In practice, this means that user code can change the SCS<1:0> bit settings or issue SLEEP instructions before the OST times out. This would allow an application to briefly wake-up, perform routine “housekeeping” tasks and return to Sleep before the device starts to operate from the primary oscillator. When enabled, Resets and wake-ups from Sleep mode cause the device to configure itself to run from the internal oscillator block as the clock source, following the time-out of the Power-up Timer after a Power-on Reset is enabled. This allows almost immediate code execution while the primary oscillator starts and the OST is running. Once the OST times out, the device automatically switches to PRI_RUN mode. User code can also check if the primary clock source is currently providing the device clocking by checking the status of the OSTS bit (OSCCON<3>). If the bit is set, the primary oscillator is providing the clock. Otherwise, the internal oscillator block is providing the clock during wake-up from Reset or Sleep mode. To use a higher clock speed on wake-up, the INTOSC or postscaler clock sources can be selected to provide a higher clock speed by setting bits, IRCF<2:0>, immediately after Reset. For wake-ups from Sleep, the INTOSC or postscaler clock sources can be selected by setting the IRCF2:0> bits prior to entering Sleep mode. FIGURE 28-3: SPECIAL CONSIDERATIONS FOR USING TWO-SPEED START-UP TIMING TRANSITION FOR TWO-SPEED START-UP (INTOSC TO HSPLL) Q1 Q3 Q2 Q4 Q2 Q3 Q4 Q1 Q2 Q3 Q1 INTOSC Multiplexer OSC1 TOST(1) TPLL(1) 1 PLL Clock Output 2 n-1 n Clock Transition(2) CPU Clock Peripheral Clock Program Counter PC Wake from Interrupt Event Note 1: 2: DS39957B-page 442 PC + 2 PC + 4 PC + 6 OSTS bit Set TOST = 1024 TOSC; TPLL = 2 ms (approx). These intervals are not shown to scale. Clock transition typically occurs within 2-4 TOSC. Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 28.5 Fail-Safe Clock Monitor The Fail-Safe Clock Monitor (FSCM) allows the microcontroller to continue operation in the event of an external oscillator failure by automatically switching the device clock to the internal oscillator block. The FSCM function is enabled by setting the FCMEN Configuration bit. When FSCM is enabled, the LF-INTOSC oscillator runs at all times to monitor clocks to peripherals and provide a backup clock in the event of a clock failure. Clock monitoring (shown in Figure 28-4) is accomplished by creating a sample clock signal, which is the output from the LF-INTOSC divided by 64. This allows ample time between FSCM sample clocks for a peripheral clock edge to occur. The peripheral device clock and the sample clock are presented as inputs to the Clock Monitor (CM) latch. The CM is set on the falling edge of the device clock source, but cleared on the rising edge of the sample clock. FIGURE 28-4: FSCM BLOCK DIAGRAM Clock Monitor Latch (CM) (edge-triggered) Peripheral Clock INTRC Source (32 s) ÷ 64 S Q C Q The FSCM will detect only failures of the primary or secondary clock sources. If the internal oscillator block fails, no failure would be detected nor would any action be possible. 28.5.1 Clock Failure Detected Clock failure is tested for on the falling edge of the sample clock. If a sample clock falling edge occurs while CM is still set, a clock failure has been detected (Figure 28-5). This causes the following: • The FSCM generates an oscillator fail interrupt by setting bit, OSCFIF (PIR2<7>) • The device clock source switches to the internal oscillator block (OSCCON is not updated to show the current clock source – this is the fail-safe condition) • The WDT is reset During switchover, the postscaler frequency from the internal oscillator block may not be sufficiently stable for timing-sensitive applications. In these cases, it may be desirable to select another clock configuration and enter an alternate power-managed mode. This can be done to attempt a partial recovery or execute a controlled shutdown. See Section 4.1.4 “Multiple Sleep Commands” and Section 28.4.1 “Special Considerations for Using Two-Speed Start-up” for more details. FSCM AND THE WATCHDOG TIMER Both the FSCM and the WDT are clocked by the INTOSC oscillator. Since the WDT operates with a separate divider and counter, disabling the WDT has no effect on the operation of the INTOSC oscillator when the FSCM is enabled. As already noted, the clock source is switched to the INTOSC clock when a clock failure is detected. Depending on the frequency selected by the IRCF<2:0> bits, this may mean a substantial change in the speed of code execution. If the WDT is enabled with a small prescale value, a decrease in clock speed allows a WDT time-out to occur and a subsequent device Reset. For this reason, Fail-Safe Clock events also reset the WDT and postscaler, allowing it to start timing from when execution speed was changed, and decreasing the likelihood of an erroneous time-out. 28.5.2 488 Hz (2.048 ms) 2010 Microchip Technology Inc. To use a higher clock speed on wake-up, the INTOSC or postscaler clock sources can be selected to provide a higher clock speed by setting bits, IRCF<2:0>, immediately after Reset. For wake-ups from Sleep, the INTOSC or postscaler clock sources can be selected by setting the IRCF<2:0> bits prior to entering Sleep mode. EXITING FAIL-SAFE OPERATION The Fail-Safe condition is terminated by either a device Reset or by entering a power-managed mode. On Reset, the controller starts the primary clock source specified in Configuration Register 1H (with any required start-up delays that are required for the oscillator mode, such as the OST or PLL timer). The INTOSC multiplexer provides the device clock until the primary clock source becomes ready (similar to a TwoSpeed Start-up). The clock source is then switched to the primary clock (indicated by the OSTS bit in the OSCCON register becoming set). The Fail-Safe Clock Monitor then resumes monitoring the peripheral clock. The primary clock source may never become ready during start-up. In this case, operation is clocked by the INTOSC multiplexer. The OSCCON register will remain in its Reset state until a power-managed mode is entered. Preliminary DS39957B-page 443 PIC18F87K90 FAMILY FIGURE 28-5: FSCM TIMING DIAGRAM Sample Clock Oscillator Failure Device Clock Output CM Output (Q) Failure Detected OSCFIF CM Test Note: 28.5.3 CM Test FSCM INTERRUPTS IN POWER-MANAGED MODES By entering a power-managed mode, the clock multiplexer selects the clock source selected by the OSCCON register. Fail-Safe Monitoring of the powermanaged clock source resumes in the power-managed mode. If an oscillator failure occurs during power-managed operation, the subsequent events depend on whether or not the oscillator failure interrupt is enabled. If enabled (OSCFIF = 1), code execution will be clocked by the INTOSC multiplexer. An automatic transition back to the failed clock source will not occur. For oscillator modes involving a crystal or resonator (HS, HSPLL, LP or XT), the situation is somewhat different. Since the oscillator may require a start-up time considerably longer than the FCSM sample clock time, a false clock failure may be detected. To prevent this, the internal oscillator block is automatically configured as the device clock and functions until the primary clock is stable (when the OST and PLL timers have timed out). This is identical to Two-Speed Start-up mode. Once the primary clock is stable, the INTOSC returns to its role as the FSCM source. Note: If the interrupt is disabled, subsequent interrupts while in Idle mode will cause the CPU to begin executing instructions while being clocked by the INTOSC source. 28.5.4 CM Test The device clock is normally at a much higher frequency than the sample clock. The relative frequencies in this example have been chosen for clarity. POR OR WAKE FROM SLEEP The FSCM is designed to detect oscillator failure at any point after the device has exited Power-on Reset (POR) or low-power Sleep mode. When the primary device clock is EC, RC or INTRC modes, monitoring can begin immediately following these events. DS39957B-page 444 The same logic that prevents false oscillator failure interrupts on POR, or wake from Sleep, also prevents the detection of the oscillator’s failure to start at all following these events. This can be avoided by monitoring the OSTS bit and using a timing routine to determine if the oscillator is taking too long to start. Even so, no oscillator failure interrupt will be flagged. As noted in Section 28.4.1 “Special Considerations for Using Two-Speed Start-up”, it is also possible to select another clock configuration and enter an alternate power-managed mode while waiting for the primary clock to become stable. When the new powermanaged mode is selected, the primary clock is disabled. Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 28.6 Program Verification and Code Protection Each of the blocks has three code protection bits associated with them. They are: • Code-Protect bit (CPn) • Write-Protect bit (WRTn) • External Block Table Read bit (EBTRn) The user program memory is divided into four blocks for the PIC18FX5K90 device and PIC18FX6K90 devices, and eight blocks for PIC18FX7K90 devices. One of these is a boot block of 1 or 2 Kbytes. The remainder of the memory is divided into blocks on binary boundaries. FIGURE 28-6: Figure 28-6 shows the program memory organization for 48, 64, 96 and 128-Kbyte devices and the specific code protection bit associated with each block. The actual locations of the bits are summarized in Table 28-4. CODE-PROTECTED PROGRAM MEMORY FOR THE PIC18F87K90 FAMILY 000000h 01FFFFh Code Memory Device/Memory Size PIC18FX7K90 PIC18FX6K90 PIC18FX5K90 BBSIZ = 1 BBSIZ = 0 BBSIZ = 1 BBSIZ = 0 BBSIZ = 1 BBSIZ = 0 Address Unimplemented Read as ‘0’ Boot Block 2 kW Block 0 6 kW 200000h Configuration and ID Space Boot Block Block 0 7 kW Boot Block 2 kW Block 0 6 kW Block 1 8 kW Boot Block Block 0 7 kW Block 1 8 kW Boot Block 2 kW Boot Block 0000h Block 0 2 kW Block 0 0800h 3 kW 1000h 17FFh Block 1 4 kW Block 1 1800 4 kW 3FFF Block 2 4 kW Block 2 4000h 4 kW 5FFFh Block 3 4 kW Block 3 6000h 4 kW 7FFF Block 1 8 kW Block 1 8 kW Block 2 8 kW Block 2 8 kW Block 2 8 kW Block 2 8 kW 8000h BFFFh Block 3 8 kW Block 3 8 kW Block 3 8 kW Block 3 8 kW C000h FFFFh Block 4 8 kW Block 4 8 kW 10000h 13FFFh Block 5 8 kW Block 5 8 kW 14000h 17FFFh Block 6 8 kW Block 6 8 kW 18000h 1BFFFh Block 7 8 kW Block 7 8 kW 1C000h 1FFFFh 3FFFFFh Note 1: Sizes of memory areas are not to scale. 2: Boot block size is determined by the BBSIZ0 bit (CONFIG4L<4>). 2010 Microchip Technology Inc. Preliminary DS39957B-page 445 PIC18F87K90 FAMILY TABLE 28-4: SUMMARY OF CODE PROTECTION REGISTERS File Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 300008h CONFIG5L CP7(1) CP6(1) CP5(1) CP4(1) CP3 CP2 CP1 CP0 300009h CONFIG5H CPD CPB — — — — — — WRT3 WRT2 WRT1 WRT0 — — — — EBTR3 EBTR2 EBTR1 EBTR0 — — — — 30000Ah CONFIG6L WRT7 (1) 30000Bh CONFIG6H WRTD 30000Ch CONFIG7L EBRT7(1) 30000Dh CONFIG7H — (1) WRT6 WRTB EBRT6 (1) EBTRB WRT5 (1) WRT4 WRTC EBTR5 (1) (1) — (1) EBTR4 — — Legend: Shaded cells are unimplemented. Note 1: This bit is available only on the PIC18F67K90 and PIC18F87K90 devices. 28.6.1 PROGRAM MEMORY CODE PROTECTION The program memory may be read to, or written from, any location using the table read and table write instructions. The Device ID may be read with table reads. The Configuration registers may be read and written with the table read and table write instructions. location outside of that block is not allowed to read and will result in reading ‘0’s. Figures 28-7 through 28-9 illustrate table write and table read protection. Note: In normal execution mode, the CPn bits have no direct effect. CPn bits inhibit external reads and writes. A block of user memory may be protected from table writes if the WRTn Configuration bit is ‘0’. The EBTRn bits control table reads. For a block of user memory with the EBTRn bit set to ‘0’, a table read instruction that executes from within that block is allowed to read. A table read instruction that executes from a FIGURE 28-7: Code protection bits may only be written to a ‘0’ from a ‘1’ state. It is not possible to write a ‘1’ to a bit in the ‘0’ state. Code protection bits are only set to ‘1’ by a full chip erase or block erase function. The full chip erase and block erase functions can only be initiated via ICSP or an external programmer. Refer to the device programming specification for more information. TABLE WRITE (WRTn) DISALLOWED Register Values Program Memory Configuration Bit Settings 000000h 0007FFh 000800h TBLPTR = 0008FFh PC = 003FFEh WRTB, EBTRB = 11 WRT0, EBTR0 = 01 TBLWT* 003FFFh 004000h WRT1, EBTR1 = 11 007FFFh 008000h PC = 00BFFEh WRT2, EBTR2 = 11 TBLWT* 00BFFFh 00C000h WRT3, EBTR3 = 11 00FFFFh Results: All table writes are disabled to Blockn whenever WRTn = 0. DS39957B-page 446 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY FIGURE 28-8: EXTERNAL BLOCK TABLE READ (EBTRn) DISALLOWED Register Values Program Memory Configuration Bit Settings 000000h 0007FFh 000800h TBLPTR = 0008FFh WRTB, EBTRB = 11 WRT0, EBTR0 = 10 003FFFh 004000h PC = 007FFEh WRT1, EBTR1 = 11 TBLRD* 007FFFh 008000h WRT2, EBTR2 = 11 00BFFFh 00C000h WRT3, EBTR3 = 11 00FFFFh Results: All table reads from external blocks to Blockn are disabled whenever EBTRn = 0. The TABLAT register returns a value of ‘0’. FIGURE 28-9: EXTERNAL BLOCK TABLE READ (EBTRn) ALLOWED Register Values Program Memory Configuration Bit Settings 000000h 0007FFh 000800h TBLPTR = 0008FFh PC = 003FFEh WRTB, EBTRB = 11 WRT0, EBTR0 = 10 TBLRD* 003FFFh 004000h WRT1, EBTR1 = 11 007FFFh 008000h WRT2, EBTR2 = 11 00BFFFh 00C000h WRT3, EBTR3 = 11 00FFFFh Results: Table reads are permitted within Blockn, even when EBTRBn = 0. The TABLAT register returns the value of the data at the location, TBLPTR. 2010 Microchip Technology Inc. Preliminary DS39957B-page 447 PIC18F87K90 FAMILY 28.6.2 28.9 DATA EEPROM CODE PROTECTION The entire data EEPROM is protected from external reads and writes by two bits: CPD and WRTD. CPD inhibits external reads and writes of data EEPROM. WRTD inhibits internal and external writes to data EEPROM. The CPU can always read data EEPROM under normal operation, regardless of the protection bit settings. 28.6.3 ID Locations Eight memory locations (200000h-200007h) are designated as ID locations, where the user can store checksum or other code identification numbers. These locations are both readable and writable during normal execution through the TBLRD and TBLWT instructions or during program/verify. The ID locations can be read when the device is code-protected. 28.8 When the DEBUG Configuration bit is programmed to a ‘0’, the In-Circuit Debugger functionality is enabled. This function allows simple debugging functions when used with MPLAB® IDE. When the microcontroller has this feature enabled, some resources are not available for general use. Table 28-5 shows which resources are required by the background debugger. TABLE 28-5: CONFIGURATION REGISTER PROTECTION The Configuration registers can be write-protected. The WRTC bit controls protection of the Configuration registers. In normal execution mode, the WRTC bit is readable only. WRTC can only be written via ICSP or an external programmer. 28.7 In-Circuit Debugger DEBUGGER RESOURCES I/O Pins: RB6, RB7 Stack: Two Levels Program Memory: 512 Bytes Data Memory: 10 Bytes To use the In-Circuit Debugger function of the microcontroller, the design must implement In-Circuit Serial Programming connections to MCLR/RG5/VPP, VDD, VSS, RB7 and RB6. This will interface to the In-Circuit Debugger module available from Microchip or one of the third party development tool companies. In-Circuit Serial Programming The PIC18F87K90 family of devices can be serially programmed while in the end application circuit. This is simply done with two lines for clock and data, and three other lines for power, ground and the programming voltage. This allows customers to manufacture boards with unprogrammed devices and then program the microcontroller just before shipping the product. This also allows the most recent firmware or a custom firmware to be programmed. For the various programming modes, please refer to the device programming specification. DS39957B-page 448 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 29.0 INSTRUCTION SET SUMMARY The PIC18F87K90 family of devices incorporates the standard set of 75 PIC18 core instructions, as well as an extended set of 8 new instructions for the optimization of code that is recursive or that utilizes a software stack. The extended set is discussed later in this section. 29.1 Standard Instruction Set The standard PIC18 MCU instruction set adds many enhancements to the previous PIC® MCU instruction sets, while maintaining an easy migration from these PIC MCU instruction sets. Most instructions are a single program memory word (16 bits), but there are four instructions that require two program memory locations. Each single-word instruction is a 16-bit word divided into an opcode, which specifies the instruction type and one or more operands, which further specify the operation of the instruction. The instruction set is highly orthogonal and is grouped into four basic categories: • • • • Byte-oriented operations Bit-oriented operations Literal operations Control operations The PIC18 instruction set summary in Table 29-2 lists byte-oriented, bit-oriented, literal and control operations. Table 29-1 shows the opcode field descriptions. Most byte-oriented instructions have three operands: 1. 2. 3. The file register (specified by ‘f’) The destination of the result (specified by ‘d’) The accessed memory (specified by ‘a’) The file register designator, ‘f’, specifies which file register is to be used by the instruction. The destination designator, ‘d’, specifies where the result of the operation is to be placed. If ‘d’ is zero, the result is placed in the WREG register. If ‘d’ is one, the result is placed in the file register specified in the instruction. All bit-oriented instructions have three operands: 1. 2. 3. The file register (specified by ‘f’) The bit in the file register (specified by ‘b’) The accessed memory (specified by ‘a’) The literal instructions may use some of the following operands: • A literal value to be loaded into a file register (specified by ‘k’) • The desired FSR register to load the literal value into (specified by ‘f’) • No operand required (specified by ‘—’) The control instructions may use some of the following operands: • A program memory address (specified by ‘n’) • The mode of the CALL or RETURN instructions (specified by ‘s’) • The mode of the table read and table write instructions (specified by ‘m’) • No operand required (specified by ‘—’) All instructions are a single word, except for four double-word instructions. These instructions were made double-word to contain the required information in 32 bits. In the second word, the 4 MSbs are ‘1’s. If this second word is executed as an instruction (by itself), it will execute as a NOP. All single-word instructions are executed in a single instruction cycle, unless a conditional test is true or the program counter is changed as a result of the instruction. In these cases, the execution takes two instruction cycles with the additional instruction cycle(s) executed as a NOP. The double-word instructions execute in two instruction cycles. One instruction cycle consists of four oscillator periods. Thus, for an oscillator frequency of 4 MHz, the normal instruction execution time is 1 s. If a conditional test is true, or the program counter is changed as a result of an instruction, the instruction execution time is 2 s. Two-word branch instructions (if true) would take 3 s. Figure 29-1 shows the general formats that the instructions can have. All examples use the convention ‘nnh’ to represent a hexadecimal number. The Instruction Set Summary, shown in Table 29-2, lists the standard instructions recognized by the Microchip MPASMTM Assembler. Section 29.1.1 “Standard Instruction Set” provides a description of each instruction. The bit field designator, ‘b’, selects the number of the bit affected by the operation, while the file register designator, ‘f’, represents the number of the file in which the bit is located. 2010 Microchip Technology Inc. Preliminary DS39957B-page 449 PIC18F87K90 FAMILY TABLE 29-1: OPCODE FIELD DESCRIPTIONS Field a bbb BSR C, DC, Z, OV, N d dest f fs fd GIE k label mm * *+ *+* n PC PCL PCH PCLATH PCLATU PD PRODH PRODL s TBLPTR TABLAT TO TOS u WDT WREG x zs zd { } [text] (text) [expr]<n> < > italics DS39957B-page 450 Description RAM access bit: a = 0: RAM location in Access RAM (BSR register is ignored) a = 1: RAM bank is specified by BSR register Bit address within an 8-bit file register (0 to 7). Bank Select Register. Used to select the current RAM bank. ALU Status bits: Carry, Digit Carry, Zero, Overflow, Negative. Destination select bit: d = 0: store result in WREG d = 1: store result in file register f Destination: either the WREG register or the specified register file location. 8-bit register file address (00h to FFh), or 2-bit FSR designator (0h to 3h). 12-bit register file address (000h to FFFh). This is the source address. 12-bit register file address (000h to FFFh). This is the destination address. Global Interrupt Enable bit. Literal field, constant data or label (may be either an 8-bit, 12-bit or a 20-bit value). Label name. The mode of the TBLPTR register for the table read and table write instructions. Only used with table read and table write instructions: No Change to register (such as TBLPTR with table reads and writes) Post-Increment register (such as TBLPTR with table reads and writes) Post-Decrement register (such as TBLPTR with table reads and writes) Pre-Increment register (such as TBLPTR with table reads and writes) The relative address (2’s complement number) for relative branch instructions or the direct address for Call/Branch and Return instructions. Program Counter. Program Counter Low Byte. Program Counter High Byte. Program Counter High Byte Latch. Program Counter Upper Byte Latch. Power-Down bit. Product of Multiply High Byte. Product of Multiply Low Byte. Fast Call/Return mode select bit: s = 0: do not update into/from shadow registers s = 1: certain registers loaded into/from shadow registers (Fast mode) 21-bit Table Pointer (points to a Program Memory location). 8-bit Table Latch. Time-out bit. Top-of-Stack. Unused or Unchanged. Watchdog Timer. Working register (accumulator). Don’t care (‘0’ or ‘1’). The assembler will generate code with x = 0. It is the recommended form of use for compatibility with all Microchip software tools. 7-bit offset value for Indirect Addressing of register files (source). 7-bit offset value for Indirect Addressing of register files (destination). Optional argument. Indicates an Indexed Address. The contents of text. Specifies bit n of the register indicated by the pointer expr. Assigned to. Register bit field. In the set of. User-defined term (font is Courier New). Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY FIGURE 29-1: GENERAL FORMAT FOR INSTRUCTIONS Byte-oriented file register operations 15 10 9 OPCODE Example Instruction 8 7 d 0 a f (FILE #) ADDWF MYREG, W, B d = 0 for result destination to be WREG register d = 1 for result destination to be file register (f) a = 0 to force Access Bank a = 1 for BSR to select bank f = 8-bit file register address Byte to Byte move operations (2-word) 15 12 11 0 OPCODE 15 f (Source FILE #) 12 11 MOVFF MYREG1, MYREG2 0 f (Destination FILE #) 1111 f = 12-bit file register address Bit-oriented file register operations 15 12 11 9 8 7 0 OPCODE b (BIT #) a f (FILE #) BSF MYREG, bit, B b = 3-bit position of bit in file register (f) a = 0 to force Access Bank a = 1 for BSR to select bank f = 8-bit file register address Literal operations 15 8 7 0 OPCODE k (literal) MOVLW 7Fh k = 8-bit immediate value Control operations CALL, GOTO and Branch operations 15 8 7 0 OPCODE 15 n<7:0> (literal) 12 11 GOTO Label 0 n<19:8> (literal) 1111 n = 20-bit immediate value 15 8 7 OPCODE 15 S 0 n<7:0> (literal) 12 11 CALL MYFUNC 0 n<19:8> (literal) 1111 S = Fast bit 15 11 10 OPCODE 15 0 n<10:0> (literal) 8 7 OPCODE 2010 Microchip Technology Inc. BRA MYFUNC 0 n<7:0> (literal) Preliminary BC MYFUNC DS39957B-page 451 PIC18F87K90 FAMILY TABLE 29-2: PIC18F87K90 FAMILY INSTRUCTION SET Mnemonic, Operands Description Cycles 16-Bit Instruction Word MSb LSb Status Affected Notes BYTE-ORIENTED OPERATIONS ADDWF ADDWFC ANDWF CLRF COMF CPFSEQ CPFSGT CPFSLT DECF DECFSZ DCFSNZ INCF INCFSZ INFSNZ IORWF MOVF MOVFF f, d, a f, d, a f, d, a f, a f, d, a f, a f, a f, a f, d, a f, d, a f, d, a f, d, a f, d, a f, d, a f, d, a f, d, a fs, fd MOVWF MULWF NEGF RLCF RLNCF RRCF RRNCF SETF SUBFWB f, a f, a f, a f, d, a f, d, a f, d, a f, d, a f, a f, d, a f, d, a SUBWF SUBWFB f, d, a Add WREG and f Add WREG and Carry bit to f AND WREG with f Clear f Complement f Compare f with WREG, Skip = Compare f with WREG, Skip > Compare f with WREG, Skip < Decrement f Decrement f, Skip if 0 Decrement f, Skip if Not 0 Increment f Increment f, Skip if 0 Increment f, Skip if Not 0 Inclusive OR WREG with f Move f Move fs (source) to 1st word fd (destination) 2nd word Move WREG to f Multiply WREG with f Negate f Rotate Left f through Carry Rotate Left f (No Carry) Rotate Right f through Carry Rotate Right f (No Carry) Set f Subtract f from WREG with Borrow Subtract WREG from f Subtract WREG from f with Borrow Swap Nibbles in f Test f, Skip if 0 Exclusive OR WREG with f 1 1 1 1 1 1 (2 or 3) 1 (2 or 3) 1 (2 or 3) 1 1 (2 or 3) 1 (2 or 3) 1 1 (2 or 3) 1 (2 or 3) 1 1 2 C, DC, Z, OV, N C, DC, Z, OV, N Z, N Z Z, N None None None C, DC, Z, OV, N None None C, DC, Z, OV, N None None Z, N Z, N None 1, 2 1, 2 1,2 2 1, 2 4 4 1, 2 1, 2, 3, 4 1, 2, 3, 4 1, 2 1, 2, 3, 4 4 1, 2 1, 2 1 1 1 1 1 1 1 1 1 1 0010 0010 0001 0110 0001 0110 0110 0110 0000 0010 0100 0010 0011 0100 0001 0101 1100 1111 0110 0000 0110 0011 0100 0011 0100 0110 0101 01da 00da 01da 101a 11da 001a 010a 000a 01da 11da 11da 10da 11da 10da 00da 00da ffff ffff 111a 001a 110a 01da 01da 00da 00da 100a 01da ffff ffff ffff ffff ffff ffff ffff ffff ffff ffff ffff ffff ffff ffff ffff ffff ffff ffff ffff ffff ffff ffff ffff ffff ffff ffff ffff ffff ffff ffff ffff ffff ffff ffff ffff ffff ffff ffff ffff ffff ffff ffff ffff ffff ffff ffff ffff ffff ffff ffff ffff ffff ffff ffff 1 1 0101 11da 0101 10da ffff ffff ffff C, DC, Z, OV, N 1, 2 ffff C, DC, Z, OV, N 0011 10da 1 1 (2 or 3) 0110 011a 0001 10da 1 ffff ffff ffff ffff None ffff None ffff Z, N None None 1, 2 C, DC, Z, OV, N C, Z, N 1, 2 Z, N C, Z, N Z, N None 1, 2 C, DC, Z, OV, N SWAPF TSTFSZ XORWF f, d, a f, a f, d, a Note 1: When a PORT register is modified as a function of itself (e.g., MOVF PORTB, 1, 0), the value used will be that value present on the pins themselves. For example, if the data latch is ‘1’ for a pin configured as input and is driven low by an external device, the data will be written back with a ‘0’. If this instruction is executed on the TMR0 register (and, where applicable, d = 1), the prescaler will be cleared if assigned. If the Program Counter (PC) is modified or a conditional test is true, the instruction requires two cycles. The second cycle is executed as a NOP. Some instructions are two-word instructions. The second word of these instructions will be executed as a NOP unless the first word of the instruction retrieves the information embedded in these 16 bits. This ensures that all program memory locations have a valid instruction. 2: 3: 4: DS39957B-page 452 Preliminary 4 1, 2 2010 Microchip Technology Inc. PIC18F87K90 FAMILY TABLE 29-2: PIC18F87K90 FAMILY INSTRUCTION SET (CONTINUED) Mnemonic, Operands Description Cycles 16-Bit Instruction Word MSb LSb Status Affected Notes BIT-ORIENTED OPERATIONS BCF BSF BTFSC BTFSS BTG f, b, a f, b, a f, b, a f, b, a f, b, a Bit Clear f Bit Set f Bit Test f, Skip if Clear Bit Test f, Skip if Set Bit Toggle f 1 1 1 (2 or 3) 1 (2 or 3) 1 1001 1000 1011 1010 0111 bbba bbba bbba bbba bbba ffff ffff ffff ffff ffff ffff ffff ffff ffff ffff None None None None None Branch if Carry Branch if Negative Branch if Not Carry Branch if Not Negative Branch if Not Overflow Branch if Not Zero Branch if Overflow Branch Unconditionally Branch if Zero Call Subroutine 1st word 2nd word Clear Watchdog Timer Decimal Adjust WREG Go to Address 1st word 2nd word No Operation No Operation Pop Top of Return Stack (TOS) Push Top of Return Stack (TOS) Relative Call Software Device Reset Return from Interrupt Enable 1 (2) 1 (2) 1 (2) 1 (2) 1 (2) 1 (2) 1 (2) 2 1 (2) 2 0010 0110 0011 0111 0101 0001 0100 0nnn 0000 110s kkkk 0000 0000 1111 kkkk 0000 xxxx 0000 0000 1nnn 0000 0000 nnnn nnnn nnnn nnnn nnnn nnnn nnnn nnnn nnnn kkkk kkkk 0000 0000 kkkk kkkk 0000 xxxx 0000 0000 nnnn 1111 0001 nnnn nnnn nnnn nnnn nnnn nnnn nnnn nnnn nnnn kkkk kkkk 0100 0111 kkkk kkkk 0000 xxxx 0110 0101 nnnn 1111 000s None None None None None None None None None None 1 1 1 1 2 1 2 1110 1110 1110 1110 1110 1110 1110 1101 1110 1110 1111 0000 0000 1110 1111 0000 1111 0000 0000 1101 0000 0000 Return with Literal in WREG Return from Subroutine Go into Standby mode 2 2 1 0000 1100 0000 0000 0000 0000 kkkk 0001 0000 1, 2 1, 2 3, 4 3, 4 1, 2 CONTROL OPERATIONS BC BN BNC BNN BNOV BNZ BOV BRA BZ CALL n n n n n n n n n n, s CLRWDT — DAW — GOTO n NOP NOP POP PUSH RCALL RESET RETFIE — — — — n s RETLW k RETURN s SLEEP — Note 1: 2: 3: 4: 1 1 2 TO, PD C None None None None None None All GIE/GIEH, PEIE/GIEL kkkk None 001s None 0011 TO, PD 4 When a PORT register is modified as a function of itself (e.g., MOVF PORTB, 1, 0), the value used will be that value present on the pins themselves. For example, if the data latch is ‘1’ for a pin configured as input and is driven low by an external device, the data will be written back with a ‘0’. If this instruction is executed on the TMR0 register (and, where applicable, d = 1), the prescaler will be cleared if assigned. If the Program Counter (PC) is modified or a conditional test is true, the instruction requires two cycles. The second cycle is executed as a NOP. Some instructions are two-word instructions. The second word of these instructions will be executed as a NOP unless the first word of the instruction retrieves the information embedded in these 16 bits. This ensures that all program memory locations have a valid instruction. 2010 Microchip Technology Inc. Preliminary DS39957B-page 453 PIC18F87K90 FAMILY TABLE 29-2: PIC18F87K90 FAMILY INSTRUCTION SET (CONTINUED) Mnemonic, Operands Description Cycles 16-Bit Instruction Word MSb LSb Status Affected Notes LITERAL OPERATIONS ADDLW ANDLW IORLW LFSR k k k f, k MOVLB MOVLW MULLW RETLW SUBLW XORLW k k k k k k Add Literal and WREG AND Literal with WREG Inclusive OR Literal with WREG Move literal (12-bit) 2nd word 1st word to FSR(f) Move Literal to BSR<3:0> Move Literal to WREG Multiply Literal with WREG Return with Literal in WREG Subtract WREG from Literal Exclusive OR Literal with WREG 1 1 1 2 1 1 1 2 1 1 0000 0000 0000 1110 1111 0000 0000 0000 0000 0000 0000 1111 1011 1001 1110 0000 0001 1110 1101 1100 1000 1010 kkkk kkkk kkkk 00ff kkkk 0000 kkkk kkkk kkkk kkkk kkkk kkkk kkkk kkkk kkkk kkkk kkkk kkkk kkkk kkkk kkkk kkkk C, DC, Z, OV, N Z, N Z, N None 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 1000 1001 1010 1011 1100 1101 1110 1111 None None None None None None None None None None None None C, DC, Z, OV, N Z, N DATA MEMORY PROGRAM MEMORY OPERATIONS TBLRD* TBLRD*+ TBLRD*TBLRD+* TBLWT* TBLWT*+ TBLWT*TBLWT+* Note 1: 2: 3: 4: Table Read 2 Table Read with Post-Increment Table Read with Post-Decrement Table Read with Pre-Increment Table Write 2 Table Write with Post-Increment Table Write with Post-Decrement Table Write with Pre-Increment When a PORT register is modified as a function of itself (e.g., MOVF PORTB, 1, 0), the value used will be that value present on the pins themselves. For example, if the data latch is ‘1’ for a pin configured as input and is driven low by an external device, the data will be written back with a ‘0’. If this instruction is executed on the TMR0 register (and, where applicable, d = 1), the prescaler will be cleared if assigned. If the Program Counter (PC) is modified or a conditional test is true, the instruction requires two cycles. The second cycle is executed as a NOP. Some instructions are two-word instructions. The second word of these instructions will be executed as a NOP unless the first word of the instruction retrieves the information embedded in these 16 bits. This ensures that all program memory locations have a valid instruction. DS39957B-page 454 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 29.1.1 STANDARD INSTRUCTION SET ADDLW ADD Literal to W ADDWF ADD W to f Syntax: ADDLW Syntax: ADDWF Operands: 0 f 255 d [0,1] a [0,1] Operation: (W) + (f) dest Status Affected: N, OV, C, DC, Z k Operands: 0 k 255 Operation: (W) + k W Status Affected: N, OV, C, DC, Z Encoding: 0000 1111 kkkk kkkk Description: The contents of W are added to the 8-bit literal ‘k’ and the result is placed in W. Words: 1 Cycles: 1 Q Cycle Activity: Q1 Decode Example: Q2 Read literal ‘k’ ADDLW Q3 Process Data Encoding: Description: Q4 Write to W ffff ffff Add W to register ‘f’. If ‘d’ is ‘0’, the result is stored in W. If ‘d’ is ‘1’, the result is stored back in register ‘f’. If ‘a’ is ‘0’ and the extended instruction set is enabled, this instruction operates in Indexed Literal Offset Addressing mode whenever f 95 (5Fh). See Section 29.2.3 “Byte-Oriented and Bit-Oriented Instructions in Indexed Literal Offset Mode” for details. Words: 1 Cycles: 1 Q Cycle Activity: Q1 Decode Example: Q2 Read register ‘f’ ADDWF Before Instruction W = REG = After Instruction W = REG = Note: 01da If ‘a’ is ‘0’, the Access Bank is selected. If ‘a’ is ‘1’, the BSR is used to select the GPR bank. 15h Before Instruction W = 10h After Instruction W = 25h 0010 f {,d {,a}} Q3 Process Data Q4 Write to destination REG, 0, 0 17h 0C2h 0D9h 0C2h All PIC18 instructions may take an optional label argument preceding the instruction mnemonic for use in symbolic addressing. If a label is used, the instruction format then becomes: {label} instruction argument(s). 2010 Microchip Technology Inc. Preliminary DS39957B-page 455 PIC18F87K90 FAMILY ADDWFC ADD W and Carry bit to f ANDLW AND Literal with W Syntax: ADDWFC Syntax: ANDLW Operands: 0 f 255 d [0,1] a [0,1] f {,d {,a}} Operation: (W) + (f) + (C) dest Status Affected: N,OV, C, DC, Z Encoding: 0010 Description: 00da ffff Add W, the Carry flag and data memory location ‘f’. If ‘d’ is ‘0’, the result is placed in W. If ‘d’ is ‘1’, the result is placed in data memory location ‘f’. If ‘a’ is ‘0’, the Access Bank is selected. If ‘a’ is ‘1’, the BSR is used to select the GPR bank. If ‘a’ is ‘0’ and the extended instruction set is enabled, this instruction operates in Indexed Literal Offset Addressing mode whenever f 95 (5Fh). See Section 29.2.3 “Byte-Oriented and Bit-Oriented Instructions in Indexed Literal Offset Mode” for details. Words: 1 Cycles: 1 Q Cycle Activity: Q1 Decode Q2 Read register ‘f’ Example: ADDWFC Before Instruction Carry bit = REG = W = After Instruction Carry bit = REG = W = DS39957B-page 456 Operands: 0 k 255 Operation: (W) .AND. k W Status Affected: N, Z Encoding: ffff Q3 Process Data k 0000 1011 kkkk kkkk Description: The contents of W are ANDed with the 8-bit literal ‘k’. The result is placed in W. Words: 1 Cycles: 1 Q Cycle Activity: Q1 Decode Example: Q2 Read literal ‘k’ ANDLW Before Instruction W = After Instruction W = Q3 Process Data Q4 Write to W 05Fh A3h 03h Q4 Write to destination REG, 0, 1 1 02h 4Dh 0 02h 50h Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY ANDWF AND W with f BC Branch if Carry Syntax: ANDWF Syntax: BC Operands: 0 f 255 d [0,1] a [0,1] f {,d {,a}} Operation: (W) .AND. (f) dest Status Affected: N, Z Encoding: Description: 0001 Operands: -128 n 127 Operation: if Carry bit is ‘1’, (PC) + 2 + 2n PC Status Affected: None Encoding: 01da ffff ffff Description: The contents of W are ANDed with register ‘f’. If ‘d’ is ‘0’, the result is stored in W. If ‘d’ is ‘1’, the result is stored back in register ‘f’. Words: 1 Cycles: 1 Q Cycle Activity: Q1 Decode Example: Q2 Read register ‘f’ ANDWF Before Instruction W = REG = After Instruction W = REG = Q3 Process Data REG, 0, 0 Q4 Write to destination Words: 1 Cycles: 1(2) Q Cycle Activity: If Jump: Q1 Decode No operation If No Jump: Q1 Decode Example: 0010 nnnn nnnn Q2 Read literal ‘n’ No operation Q3 Process Data No operation Q4 Write to PC No operation Q2 Read literal ‘n’ Q3 Process Data Q4 No operation HERE Before Instruction PC After Instruction If Carry PC If Carry PC 17h C2h 02h C2h 2010 Microchip Technology Inc. 1110 If the Carry bit is ’1’, then the program will branch. The 2’s complement number ‘2n’ is added to the PC. Since the PC will have incremented to fetch the next instruction, the new address will be PC + 2 + 2n. This instruction is then a two-cycle instruction. If ‘a’ is ‘0’, the Access Bank is selected. If ‘a’ is ‘1’, the BSR is used to select the GPR bank. If ‘a’ is ‘0’ and the extended instruction set is enabled, this instruction operates in Indexed Literal Offset Addressing mode whenever f 95 (5Fh). See Section 29.2.3 “Byte-Oriented and Bit-Oriented Instructions in Indexed Literal Offset Mode” for details. n Preliminary BC 5 = address (HERE) = = = = 1; address (HERE + 12) 0; address (HERE + 2) DS39957B-page 457 PIC18F87K90 FAMILY BCF Bit Clear f BN Branch if Negative Syntax: BCF Syntax: BN Operands: 0 f 255 0b7 a [0,1] f, b {,a} Operation: 0 f<b> Status Affected: None Encoding: 1001 Description: Operands: -128 n 127 Operation: if Negative bit is ‘1’, (PC) + 2 + 2n PC Status Affected: None Encoding: bbba ffff ffff Description: Bit ‘b’ in register ‘f’ is cleared. Words: 1 Cycles: 1 Q Cycle Activity: Q1 Decode Q2 Read register ‘f’ Example: BCF Before Instruction FLAG_REG = C7h After Instruction FLAG_REG = 47h DS39957B-page 458 Q3 Process Data FLAG_REG, Q4 Write register ‘f’ 7, 0 1110 0110 nnnn nnnn If the Negative bit is ‘1’, then the program will branch. The 2’s complement number ‘2n’ is added to the PC. Since the PC will have incremented to fetch the next instruction, the new address will be PC + 2 + 2n. This instruction is then a two-cycle instruction. If ‘a’ is ‘0’, the Access Bank is selected. If ‘a’ is ‘1’, the BSR is used to select the GPR bank. If ‘a’ is ‘0’ and the extended instruction set is enabled, this instruction operates in Indexed Literal Offset Addressing mode whenever f 95 (5Fh). See Section 29.2.3 “Byte-Oriented and Bit-Oriented Instructions in Indexed Literal Offset Mode” for details. n Words: 1 Cycles: 1(2) Q Cycle Activity: If Jump: Q1 Decode No operation If No Jump: Q1 Decode Example: Q2 Read literal ‘n’ No operation Q3 Process Data No operation Q4 Write to PC No operation Q2 Read literal ‘n’ Q3 Process Data Q4 No operation HERE Before Instruction PC After Instruction If Negative PC If Negative PC Preliminary BN Jump = address (HERE) = = = = 1; address (Jump) 0; address (HERE + 2) 2010 Microchip Technology Inc. PIC18F87K90 FAMILY BNC Branch if Not Carry BNN Branch if Not Negative Syntax: BNC Syntax: BNN n n Operands: -128 n 127 Operands: -128 n 127 Operation: if Carry bit is ‘0’, (PC) + 2 + 2n PC Operation: if Negative bit is ‘0’, (PC) + 2 + 2n PC Status Affected: None Status Affected: None Encoding: Description: 1110 0011 nnnn nnnn If the Carry bit is ‘0’, then the program will branch. Encoding: Description: The 2’s complement number ‘2n’ is added to the PC. Since the PC will have incremented to fetch the next instruction, the new address will be PC + 2 + 2n. This instruction is then a two-cycle instruction. 1110 1 Words: 1 Cycles: 1(2) Cycles: 1(2) No operation If No Jump: Q1 Decode Example: Q2 Read literal ‘n’ No operation Q3 Process Data No operation Q4 Write to PC No operation Q2 Read literal ‘n’ Q3 Process Data Q4 No operation HERE Before Instruction PC After Instruction If Carry PC If Carry PC BNC Jump = address (HERE) = = = = 0; address (Jump) 1; address (HERE + 2) 2010 Microchip Technology Inc. nnnn nnnn The 2’s complement number ‘2n’ is added to the PC. Since the PC will have incremented to fetch the next instruction, the new address will be PC + 2 + 2n. This instruction is then a two-cycle instruction. Words: Q Cycle Activity: If Jump: Q1 Decode 0111 If the Negative bit is ‘0’, then the program will branch. Q Cycle Activity: If Jump: Q1 Decode No operation If No Jump: Q1 Decode Example: Q2 Read literal ‘n’ No operation Q3 Process Data No operation Q4 Write to PC No operation Q2 Read literal ‘n’ Q3 Process Data Q4 No operation HERE Before Instruction PC After Instruction If Negative PC If Negative PC Preliminary BNN Jump = address (HERE) = = = = 0; address (Jump) 1; address (HERE + 2) DS39957B-page 459 PIC18F87K90 FAMILY BNOV Branch if Not Overflow BNZ Branch if Not Zero Syntax: BNOV Syntax: BNZ n n Operands: -128 n 127 Operands: -128 n 127 Operation: if Overflow bit is ‘0’, (PC) + 2 + 2n PC Operation: if Zero bit is ‘0’, (PC) + 2 + 2n PC Status Affected: None Status Affected: None Encoding: 1110 Description: 0101 nnnn nnnn If the Overflow bit is ‘0’, then the program will branch. Encoding: Description: The 2’s complement number ‘2n’ is added to the PC. Since the PC will have incremented to fetch the next instruction, the new address will be PC + 2 + 2n. This instruction is then a two-cycle instruction. 1110 1 Words: 1 Cycles: 1(2) Cycles: 1(2) No operation If No Jump: Q1 Decode Q2 Read literal ‘n’ No operation Q3 Process Data No operation Q4 Write to PC No operation Q2 Read literal ‘n’ Q3 Process Data Q4 No operation Example: HERE Before Instruction PC After Instruction If Overflow PC If Overflow PC DS39957B-page 460 BNOV Jump = address (HERE) = = = = 0; address (Jump) 1; address (HERE + 2) nnnn nnnn The 2’s complement number ‘2n’ is added to the PC. Since the PC will have incremented to fetch the next instruction, the new address will be PC + 2 + 2n. This instruction is then a two-cycle instruction. Words: Q Cycle Activity: If Jump: Q1 Decode 0001 If the Zero bit is ‘0’, then the program will branch. Q Cycle Activity: If Jump: Q1 Decode No operation If No Jump: Q1 Decode Example: Q2 Read literal ‘n’ No operation Q3 Process Data No operation Q4 Write to PC No operation Q2 Read literal ‘n’ Q3 Process Data Q4 No operation HERE Before Instruction PC After Instruction If Zero PC If Zero PC Preliminary BNZ Jump = address (HERE) = = = = 0; address (Jump) 1; address (HERE + 2) 2010 Microchip Technology Inc. PIC18F87K90 FAMILY BRA Unconditional Branch BSF Bit Set f Syntax: BRA Syntax: BSF Operands: 0 f 255 0b7 a [0,1] Operation: 1 f<b> Status Affected: None n Operands: -1024 n 1023 Operation: (PC) + 2 + 2n PC Status Affected: None Encoding: Description: 1101 1 Cycles: 2 No operation Example: nnnn nnnn Add the 2’s complement number ‘2n’ to the PC. Since the PC will have incremented to fetch the next instruction, the new address will be PC + 2 + 2n. This instruction is a two-cycle instruction. Words: Q Cycle Activity: Q1 Decode 0nnn Q2 Read literal ‘n’ No operation HERE Before Instruction PC After Instruction PC Q3 Process Data No operation BRA Jump = address (HERE) = address (Jump) Q4 Write to PC No operation Encoding: Description: 1000 bbba ffff ffff Bit ‘b’ in register ‘f’ is set. If ‘a’ is ‘0’, the Access Bank is selected. If ‘a’ is ‘1’, the BSR is used to select the GPR bank. If ‘a’ is ‘0’ and the extended instruction set is enabled, this instruction operates in Indexed Literal Offset Addressing mode whenever f 95 (5Fh). See Section 29.2.3 “Byte-Oriented and Bit-Oriented Instructions in Indexed Literal Offset Mode” for details. Words: 1 Cycles: 1 Q Cycle Activity: Q1 Decode Example: Q2 Read register ‘f’ BSF Before Instruction FLAG_REG After Instruction FLAG_REG 2010 Microchip Technology Inc. f, b {,a} Preliminary Q3 Process Data Q4 Write register ‘f’ FLAG_REG, 7, 1 = 0Ah = 8Ah DS39957B-page 461 PIC18F87K90 FAMILY BTFSC Bit Test File, Skip if Clear BTFSS Bit Test File, Skip if Set Syntax: BTFSC f, b {,a} Syntax: BTFSS f, b {,a} Operands: 0 f 255 0b7 a [0,1] Operands: 0 f 255 0b<7 a [0,1] Operation: skip if (f<b>) = 0 Operation: skip if (f<b>) = 1 Status Affected: None Status Affected: None Encoding: Description: 1011 bbba ffff ffff If bit ‘b’ in register ‘f’ is ‘0’, then the next instruction is skipped. If bit ‘b’ is ‘0’, then the next instruction fetched during the current instruction execution is discarded and a NOP is executed instead, making this a two-cycle instruction. Encoding: Description: 1010 If ‘a’ is ‘0’, the Access Bank is selected. If ‘a’ is ‘1’, the BSR is used to select the GPR bank. If ‘a’ is ‘0’ and the extended instruction set is enabled, this instruction operates in Indexed Literal Offset Addressing mode whenever f 95 (5Fh). See Section 29.2.3 “Byte-Oriented and Bit-Oriented Instructions in Indexed Literal Offset Mode” for details. If ‘a’ is ‘0’ and the extended instruction set is enabled, this instruction operates in Indexed Literal Offset Addressing mode whenever f 95 (5Fh). See Section 29.2.3 “Byte-Oriented and Bit-Oriented Instructions in Indexed Literal Offset Mode” for details. 1 Words: 1 1(2) Note: Cycles: 1(2) Note: 3 cycles if skip and followed by a 2-word instruction. Q3 Process Data Q4 No operation Q2 Read register ‘f’ Q1 Q2 Q3 No No No operation operation operation If skip and followed by 2-word instruction: Q1 Q2 Q3 No No No operation operation operation No No No operation operation operation Q4 No operation If skip: Q Cycle Activity: Q1 Decode 3 cycles if skip and followed by a 2-word instruction. Q2 Read register ‘f’ Q3 Process Data Q4 No operation Q1 Q2 Q3 No No No operation operation operation If skip and followed by 2-word instruction: Q1 Q2 Q3 No No No operation operation operation No No No operation operation operation Q4 No operation If skip: HERE FALSE TRUE Before Instruction PC After Instruction If FLAG<1> PC If FLAG<1> PC DS39957B-page 462 ffff If ‘a’ is ‘0’, the Access Bank is selected. If ‘a’ is ‘1’, the BSR is used to select the GPR bank. Cycles: Example: ffff If bit ‘b’ in register ‘f’ is ‘1’, then the next instruction is skipped. If bit ‘b’ is ‘1’, then the next instruction fetched during the current instruction execution is discarded and a NOP is executed instead, making this a two-cycle instruction. Words: Q Cycle Activity: Q1 Decode bbba BTFSC : : Q4 No operation No operation FLAG, 1, 0 = address (HERE) = = = = 0; address (TRUE) 1; address (FALSE) Example: HERE FALSE TRUE Before Instruction PC After Instruction If FLAG<1> PC If FLAG<1> PC Preliminary BTFSS : : Q4 No operation No operation FLAG, 1, 0 = address (HERE) = = = = 0; address (FALSE) 1; address (TRUE) 2010 Microchip Technology Inc. PIC18F87K90 FAMILY BTG Bit Toggle f BOV Branch if Overflow Syntax: BTG f, b {,a} Syntax: BOV Operands: 0 f 255 0b<7 a [0,1] Operation: (f<b>) f<b> Status Affected: None Encoding: Description: 0111 Operands: -128 n 127 Operation: if Overflow bit is ‘1’, (PC) + 2 + 2n PC Status Affected: None Encoding: bbba ffff ffff Description: Bit ‘b’ in data memory location, ‘f’, is inverted. Words: 1 Cycles: 1 Q Cycle Activity: Q1 Decode Example: Q2 Read register ‘f’ BTG Q3 Process Data PORTC, Words: 1 Cycles: 1(2) Q Cycle Activity: If Jump: Q1 Decode No operation If No Jump: Q1 Decode 4, 0 Before Instruction: PORTC = 0111 0101 [75h] After Instruction: 0110 0101 [65h] PORTC = 2010 Microchip Technology Inc. Q4 Write register ‘f’ 1110 0100 nnnn nnnn If the Overflow bit is ‘1’, then the program will branch. The 2’s complement number ‘2n’ is added to the PC. Since the PC will have incremented to fetch the next instruction, the new address will be PC + 2 + 2n. This instruction is then a two-cycle instruction. If ‘a’ is ‘0’, the Access Bank is selected. If ‘a’ is ‘1’, the BSR is used to select the GPR bank. If ‘a’ is ‘0’ and the extended instruction set is enabled, this instruction operates in Indexed Literal Offset Addressing mode whenever f 95 (5Fh). See Section 29.2.3 “Byte-Oriented and Bit-Oriented Instructions in Indexed Literal Offset Mode” for details. n Example: Q2 Read literal ‘n’ No operation Q3 Process Data No operation Q4 Write to PC Q2 Read literal ‘n’ Q3 Process Data Q4 No operation HERE Before Instruction PC After Instruction If Overflow PC If Overflow PC Preliminary BOV No operation Jump = address (HERE) = = = = 1; address (Jump) 0; address (HERE + 2) DS39957B-page 463 PIC18F87K90 FAMILY BZ Branch if Zero CALL Subroutine Call Syntax: BZ Syntax: CALL k {,s} n Operands: -128 n 127 Operands: Operation: if Zero bit is ‘1’, (PC) + 2 + 2n PC 0 k 1048575 s [0,1] Operation: Status Affected: None (PC) + 4 TOS, k PC<20:1>; if s = 1, (W) WS, (STATUS) STATUSS, (BSR) BSRS Status Affected: None Encoding: 1110 Description: 0000 nnnn nnnn If the Zero bit is ‘1’, then the program will branch. The 2’s complement number ‘2n’ is added to the PC. Since the PC will have incremented to fetch the next instruction, the new address will be PC + 2 + 2n. This instruction is then a two-cycle instruction. Words: 1 Cycles: 1(2) Q Cycle Activity: If Jump: Q1 Decode No operation If No Jump: Q1 Decode Q2 Read literal ‘n’ No operation Q3 Process Data No operation Q4 Write to PC No operation Q2 Read literal ‘n’ Q3 Process Data Q4 No operation Example: HERE Before Instruction PC After Instruction If Zero PC If Zero PC DS39957B-page 464 BZ Encoding: 1st word (k<7:0>) 2nd word(k<19:8>) address (HERE) = = = = 1; address (Jump) 0; address (HERE + 2) k7kkk kkkk 110s k19kkk kkkk0 kkkk8 Description: Subroutine call of entire 2-Mbyte memory range. First, return address (PC+ 4) is pushed onto the return stack. If ‘s’ = 1, the W, STATUS and BSR registers are also pushed into their respective shadow registers, WS, STATUSS and BSRS. If ‘s’ = 0, no update occurs. Then, the 20-bit value ‘k’ is loaded into PC<20:1>. CALL is a two-cycle instruction. Words: 2 Cycles: 2 Q Cycle Activity: Q1 Decode Jump = 1110 1111 No operation Example: Q2 Read literal ‘k’<7:0>, Q3 Push PC to stack No operation No operation HERE Before Instruction PC = After Instruction PC = TOS = WS = BSRS = STATUSS = Preliminary CALL Q4 Read literal ’k’<19:8>, Write to PC No operation THERE,1 address (HERE) address (THERE) address (HERE + 4) W BSR STATUS 2010 Microchip Technology Inc. PIC18F87K90 FAMILY CLRF Clear f Syntax: CLRF Operands: 0 f 255 a [0,1] f {,a} Operation: 000h f, 1Z Status Affected: Z Encoding: Description: 0110 101a ffff ffff Clears the contents of the specified register. CLRWDT Clear Watchdog Timer Syntax: CLRWDT Operands: None Operation: 000h WDT, 000h WDT postscaler, 1 TO, 1 PD Status Affected: TO, PD Encoding: Words: 1 Cycles: 1 Q Cycle Activity: Q1 Decode Example: CLRF Before Instruction FLAG_REG After Instruction FLAG_REG Q3 Process Data 5Ah = 00h 2010 Microchip Technology Inc. 0100 1 Cycles: 1 Q Cycle Activity: Q1 Decode Q4 Write register ‘f’ FLAG_REG,1 = 0000 Words: Example: Q2 Read register ‘f’ 0000 CLRWDT instruction resets the Watchdog Timer. It also resets the postscaler of the WDT. Status bits, TO and PD, are set. If ‘a’ is ‘0’, the Access Bank is selected. If ‘a’ is ‘1’, the BSR is used to select the GPR bank. If ‘a’ is ‘0’ and the extended instruction set is enabled, this instruction operates in Indexed Literal Offset Addressing mode whenever f 95 (5Fh). See Section 29.2.3 “Byte-Oriented and Bit-Oriented Instructions in Indexed Literal Offset Mode” for details. 0000 Description: Preliminary Q2 No operation Q3 Process Data Q4 No operation CLRWDT Before Instruction WDT Counter After Instruction WDT Counter WDT Postscaler TO PD = ? = = = = 00h 0 1 1 DS39957B-page 465 PIC18F87K90 FAMILY COMF Complement f CPFSEQ Syntax: COMF Syntax: CPFSEQ Operands: 0 f 255 a [0,1] Operation: (f) – (W), skip if (f) = (W) (unsigned comparison) Status Affected: None f {,d {,a}} Operands: 0 f 255 d [0,1] a [0,1] Operation: f dest Status Affected: N, Z Encoding: 0001 Description: 11da ffff ffff The contents of register ‘f’ are complemented. If ‘d’ is ‘0’, the result is stored in W. If ‘d’ is ‘1’, the result is stored back in register ‘f’. Encoding: Description: If ‘a’ is ‘0’ and the extended instruction set is enabled, this instruction operates in Indexed Literal Offset Addressing mode whenever f 95 (5Fh). See Section 29.2.3 “Byte-Oriented and Bit-Oriented Instructions in Indexed Literal Offset Mode” for details. 1 Cycles: 1 Q Cycle Activity: Q1 Decode Q2 Read register ‘f’ Example: COMF Before Instruction REG = After Instruction REG = W = 13h 13h ECh Q3 Process Data REG, 0, 0 Q4 Write to destination 0110 001a ffff ffff Compares the contents of data memory location ‘f’ to the contents of W by performing an unsigned subtraction. If ‘a’ is ‘0’, the Access Bank is selected. If ‘a’ is ‘1’, the BSR is used to select the GPR bank. If ‘a’ is ‘0’ and the extended instruction set is enabled, this instruction operates in Indexed Literal Offset Addressing mode whenever f 95 (5Fh). See Section 29.2.3 “Byte-Oriented and Bit-Oriented Instructions in Indexed Literal Offset Mode” for details. Words: 1 Cycles: 1(2) Note: 3 cycles if skip and followed by a 2-word instruction. Q Cycle Activity: Q1 Decode Q2 Read register ‘f’ Q3 Process Data Q4 No operation If skip: Q1 Q2 Q3 No No No operation operation operation If skip and followed by 2-word instruction: Q1 Q2 Q3 No No No operation operation operation No No No operation operation operation Example: HERE NEQUAL EQUAL Before Instruction PC Address W REG After Instruction If REG PC If REG PC DS39957B-page 466 f {,a} If ‘f’ = W, then the fetched instruction is discarded and a NOP is executed instead, making this a two-cycle instruction. If ‘a’ is ‘0’, the Access Bank is selected. If ‘a’ is ‘1’, the BSR is used to select the GPR bank. Words: Compare f with W, Skip if f = W Preliminary Q4 No operation Q4 No operation No operation CPFSEQ REG, 0 : : = = = HERE ? ? = = = W; Address (EQUAL) W; Address (NEQUAL) 2010 Microchip Technology Inc. PIC18F87K90 FAMILY CPFSGT Compare f with W, Skip if f > W CPFSLT Compare f with W, Skip if f < W Syntax: CPFSGT Syntax: CPFSLT Operands: 0 f 255 a [0,1] Operands: 0 f 255 a [0,1] Operation: (f) –W), skip if (f) > (W) (unsigned comparison) Operation: (f) –W), skip if (f) < (W) (unsigned comparison) Status Affected: None Status Affected: None Encoding: Description: 0110 f {,a} 010a ffff ffff Compares the contents of data memory location ‘f’ to the contents of the W by performing an unsigned subtraction. Encoding: Description: If the contents of ‘f’ are greater than the contents of WREG, then the fetched instruction is discarded and a NOP is executed instead, making this a two-cycle instruction. Words: 1 Cycles: 1(2) Note: Q Cycle Activity: Q1 Decode 3 cycles if skip and followed by a 2-word instruction. Q2 Read register ‘f’ Q3 Process Data Q4 No operation Q1 Q2 Q3 No No No operation operation operation If skip and followed by 2-word instruction: Q1 Q2 Q3 No No No operation operation operation No No No operation operation operation Q4 No operation If skip: Example: HERE NGREATER GREATER Before Instruction PC W After Instruction If REG PC If REG PC Q4 No operation No operation Address (HERE) ? = = W; Address (GREATER) W; Address (NGREATER) 2010 Microchip Technology Inc. 000a ffff ffff If ‘a’ is ‘0’, the Access Bank is selected. If ‘a’ is ‘1’, the BSR is used to select the GPR bank. Words: 1 Cycles: 1(2) Note: 3 cycles if skip and followed by a 2-word instruction. Q Cycle Activity: Q1 Decode Q3 Process Data Q4 No operation Q2 Read register ‘f’ Q1 Q2 Q3 No No No operation operation operation If skip and followed by 2-word instruction: Q1 Q2 Q3 No No No operation operation operation No No No operation operation operation Q4 No operation If skip: Example: CPFSGT REG, 0 : : = = 0110 Compares the contents of data memory location ‘f’ to the contents of W by performing an unsigned subtraction. If the contents of ‘f’ are less than the contents of W, then the fetched instruction is discarded and a NOP is executed instead, making this a two-cycle instruction. If ‘a’ is ‘0’, the Access Bank is selected. If ‘a’ is ‘1’, the BSR is used to select the GPR bank. If ‘a’ is ‘0’ and the extended instruction set is enabled, this instruction operates in Indexed Literal Offset Addressing mode whenever f 95 (5Fh). See Section 29.2.3 “Byte-Oriented and Bit-Oriented Instructions in Indexed Literal Offset Mode” for details. f {,a} Preliminary HERE NLESS LESS Before Instruction PC W After Instruction If REG PC If REG PC Q4 No operation No operation CPFSLT REG, 1 : : = = Address (HERE) ? < = = W; Address (LESS) W; Address (NLESS) DS39957B-page 467 PIC18F87K90 FAMILY DAW Decimal Adjust W Register DECF Decrement f Syntax: DAW Syntax: DECF f {,d {,a}} Operands: None Operands: Operation: If [W<3:0> > 9] or [DC = 1], then (W<3:0>) + 6 W<3:0>; else, (W<3:0>) W<3:0>; 0 f 255 d [0,1] a [0,1] Operation: (f) – 1 dest Status Affected: C, DC, N, OV, Z Encoding: If [W<7:4> > 9] or [C = 1], then (W<7:4>) + 6 W<7:4>; C =1; else, (W<7:4>) W<7:4> Status Affected: Description: 0000 0000 0000 0111 Description: DAW adjusts the 8-bit value in W, resulting from the earlier addition of two variables (each in packed BCD format) and produces a correct packed BCD result. Words: 1 Cycles: 1 Q Cycle Activity: Q1 Decode Q2 Read register W Example 1: Q4 Write W Example 2: Before Instruction W = C = DC = After Instruction W = C = DC = A5h 0 0 ffff ffff Decrement register ‘f’. If ‘d’ is ‘0’, the result is stored in W. If ‘d’ is ‘1’, the result is stored back in register ‘f’. If ‘a’ is ‘0’ and the extended instruction set is enabled, this instruction operates in Indexed Literal Offset Addressing mode whenever f 95 (5Fh). See Section 29.2.3 “Byte-Oriented and Bit-Oriented Instructions in Indexed Literal Offset Mode” for details. Words: 1 Cycles: 1 Q Cycle Activity: Q1 Decode DAW Before Instruction W = C = DC = After Instruction W = C = DC = DS39957B-page 468 Q3 Process Data 01da If ‘a’ is ‘0’, the Access Bank is selected. If ‘a’ is ‘1’, the BSR is used to select the GPR bank. C Encoding: 0000 Example: Q2 Read register ‘f’ DECF Before Instruction CNT = Z = After Instruction CNT = Z = 05h 1 0 Q3 Process Data CNT, Q4 Write to destination 1, 0 01h 0 00h 1 CEh 0 0 34h 1 0 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY DECFSZ Decrement f, Skip if 0 DCFSNZ Decrement f, Skip if Not 0 Syntax: DECFSZ f {,d {,a}} Syntax: DCFSNZ Operands: 0 f 255 d [0,1] a [0,1] Operands: 0 f 255 d [0,1] a [0,1] Operation: (f) – 1 dest, skip if result = 0 Operation: (f) – 1 dest, skip if result 0 Status Affected: None Status Affected: None Encoding: Description: 0010 11da ffff ffff The contents of register ‘f’ are decremented. If ‘d’ is ‘0’, the result is placed in W. If ‘d’ is ‘1’, the result is placed back in register ‘f’. Encoding: Description: If the result is ‘0’, the next instruction which is already fetched is discarded and a NOP is executed instead, making it a two-cycle instruction. Cycles: 1(2) Note: 3 cycles if skip and followed by a 2-word instruction. Q Cycle Activity: Q1 Decode Q2 Read register ‘f’ Q3 Process Data Words: 1 Cycles: 1(2) Note: Q4 Write to destination Q Cycle Activity: Q1 Decode Q4 No operation If skip: Example: HERE DECFSZ GOTO Q4 No operation No operation CNT, 1, 1 LOOP Example: Q2 Read register ‘f’ HERE ZERO NZERO Before Instruction TEMP After Instruction TEMP If TEMP PC If TEMP PC Address (HERE) CNT – 1 0; Address (CONTINUE) 0; Address (HERE + 2) 2010 Microchip Technology Inc. 3 cycles if skip and followed by a 2-word instruction. Q3 Process Data Q1 Q2 Q3 No No No operation operation operation If skip and followed by 2-word instruction: Q1 Q2 Q3 No No No operation operation operation No No No operation operation operation CONTINUE Before Instruction PC = After Instruction CNT = If CNT = PC = If CNT PC = ffff If ‘a’ is ‘0’ and the extended instruction set is enabled, this instruction operates in Indexed Literal Offset Addressing mode whenever f 95 (5Fh). See Section 29.2.3 “Byte-Oriented and Bit-Oriented Instructions in Indexed Literal Offset Mode” for details. If skip: Q1 Q2 Q3 No No No operation operation operation If skip and followed by 2-word instruction: Q1 Q2 Q3 No No No operation operation operation No No No operation operation operation ffff If ‘a’ is ‘0’, the Access Bank is selected. If ‘a’ is ‘1’, the BSR is used to select the GPR bank. If ‘a’ is ‘0’ and the extended instruction set is enabled, this instruction operates in Indexed Literal Offset Addressing mode whenever f 95 (5Fh). See Section 29.2.3 “Byte-Oriented and Bit-Oriented Instructions in Indexed Literal Offset Mode” for details. 1 11da The contents of register ‘f’ are decremented. If ‘d’ is ‘0’, the result is placed in W. If ‘d’ is ‘1’, the result is placed back in register ‘f’. If the result is not ‘0’, the next instruction which is already fetched is discarded and a NOP is executed instead, making it a two-cycle instruction. If ‘a’ is ‘0’, the Access Bank is selected. If ‘a’ is ‘1’, the BSR is used to select the GPR bank. Words: 0100 f {,d {,a}} Preliminary DCFSNZ : : Q4 Write to destination Q4 No operation Q4 No operation No operation TEMP, 1, 0 = ? = = = = TEMP – 1, 0; Address (ZERO) 0; Address (NZERO) DS39957B-page 469 PIC18F87K90 FAMILY GOTO Unconditional Branch INCF Increment f Syntax: GOTO k Syntax: INCF Operands: 0 f 255 d [0,1] a [0,1] Operation: (f) + 1 dest Status Affected: C, DC, N, OV, Z Operands: 0 k 1048575 Operation: k PC<20:1> Status Affected: None Encoding: 1st word (k<7:0>) 2nd word(k<19:8>) 1110 1111 1111 k19kkk k7kkk kkkk kkkk0 kkkk8 Description: GOTO allows an unconditional branch anywhere within entire 2-Mbyte memory range. The 20-bit value ‘k’ is loaded into PC<20:1>. GOTO is always a two-cycle instruction. Words: 2 Cycles: 2 Q Cycle Activity: Q1 Decode No operation Q2 Read literal ‘k’<7:0>, Q3 No operation No operation No operation Example: GOTO THERE After Instruction PC = Address (THERE) Q4 Read literal ‘k’<19:8>, Write to PC No operation Encoding: Description: 0010 10da ffff ffff The contents of register ‘f’ are incremented. If ‘d’ is ‘0’, the result is placed in W. If ‘d’ is ‘1’, the result is placed back in register ‘f’. If ‘a’ is ‘0’, the Access Bank is selected. If ‘a’ is ‘1’, the BSR is used to select the GPR bank. If ‘a’ is ‘0’ and the extended instruction set is enabled, this instruction operates in Indexed Literal Offset Addressing mode whenever f 95 (5Fh). See Section 29.2.3 “Byte-Oriented and Bit-Oriented Instructions in Indexed Literal Offset Mode” for details. Words: 1 Cycles: 1 Q Cycle Activity: Q1 Decode Example: Q2 Read register ‘f’ INCF Before Instruction CNT = Z = C = DC = After Instruction CNT = Z = C = DC = DS39957B-page 470 f {,d {,a}} Preliminary Q3 Process Data Q4 Write to destination CNT, 1, 0 FFh 0 ? ? 00h 1 1 1 2010 Microchip Technology Inc. PIC18F87K90 FAMILY INCFSZ Increment f, Skip if 0 INFSNZ Increment f, Skip if Not 0 Syntax: INCFSZ Syntax: INFSNZ 0 f 255 d [0,1] a [0,1] f {,d {,a}} f {,d {,a}} Operands: 0 f 255 d [0,1] a [0,1] Operands: Operation: (f) + 1 dest, skip if result = 0 Operation: (f) + 1 dest, skip if result 0 Status Affected: None Status Affected: None Encoding: Description: 0011 11da ffff ffff The contents of register ‘f’ are incremented. If ‘d’ is ‘0’, the result is placed in W. If ‘d’ is ‘1’, the result is placed back in register ‘f’. Encoding: Description: 0100 10da ffff ffff The contents of register ‘f’ are incremented. If ‘d’ is ‘0’, the result is placed in W. If ‘d’ is ‘1’, the result is placed back in register ‘f’. If the result is ‘0’, the next instruction which is already fetched is discarded and a NOP is executed instead, making it a two-cycle instruction. If the result is not ‘0’, the next instruction which is already fetched is discarded and a NOP is executed instead, making it a two-cycle instruction. If ‘a’ is ‘0’, the Access Bank is selected. If ‘a’ is ‘1’, the BSR is used to select the GPR bank. If ‘a’ is ‘0’, the Access Bank is selected. If ‘a’ is ‘1’, the BSR is used to select the GPR bank. If ‘a’ is ‘0’ and the extended instruction set is enabled, this instruction operates in Indexed Literal Offset Addressing mode whenever f 95 (5Fh). See Section 29.2.3 “Byte-Oriented and Bit-Oriented Instructions in Indexed Literal Offset Mode” for details. If ‘a’ is ‘0’ and the extended instruction set is enabled, this instruction operates in Indexed Literal Offset Addressing mode whenever f 95 (5Fh). See Section 29.2.3 “Byte-Oriented and Bit-Oriented Instructions in Indexed Literal Offset Mode” for details. Words: 1 Words: 1 Cycles: 1(2) Note: Cycles: 1(2) Note: 3 cycles if skip and followed by a 2-word instruction. Q Cycle Activity: Q1 Decode 3 cycles if skip and followed by a 2-word instruction. Q2 Read register ‘f’ Q3 Process Data Q4 Write to destination If skip: Q2 Read register ‘f’ Q3 Process Data Q4 Write to destination If skip: Q1 Q2 Q3 No No No operation operation operation If skip and followed by 2-word instruction: Q1 Q2 Q3 No No No operation operation operation No No No operation operation operation Example: Q Cycle Activity: Q1 Decode HERE NZERO ZERO Before Instruction PC = After Instruction CNT = If CNT = PC = If CNT PC = INCFSZ : : Q4 No operation Q4 No operation No operation CNT, 1, 0 Q1 Q2 Q3 No No No operation operation operation If skip and followed by 2-word instruction: Q1 Q2 Q3 No No No operation operation operation No No No operation operation operation Example: Before Instruction PC = After Instruction REG = If REG PC = If REG = PC = Address (HERE) CNT + 1 0; Address (ZERO) 0; Address (NZERO) 2010 Microchip Technology Inc. HERE ZERO NZERO Preliminary INFSNZ Q4 No operation Q4 No operation No operation REG, 1, 0 Address (HERE) REG + 1 0; Address (NZERO) 0; Address (ZERO) DS39957B-page 471 PIC18F87K90 FAMILY IORLW Inclusive OR Literal with W IORWF Inclusive OR W with f Syntax: IORLW k Syntax: IORWF Operands: 0 f 255 d [0,1] a [0,1] Operation: (W) .OR. (f) dest Status Affected: N, Z Operands: 0 k 255 Operation: (W) .OR. k W Status Affected: N, Z Encoding: 0000 1001 kkkk kkkk Description: The contents of W are ORed with the 8-bit literal ‘k’. The result is placed in W. Words: 1 Cycles: 1 Q Cycle Activity: Q1 Decode Example: Q2 Read literal ‘k’ IORLW Before Instruction W = After Instruction W = Q3 Process Data Encoding: Description: Q4 Write to W ffff ffff Inclusive OR W with register ‘f’. If ‘d’ is ‘0’, the result is placed in W. If ‘d’ is ‘1’, the result is placed back in register ‘f’. If ‘a’ is ‘0’ and the extended instruction set is enabled, this instruction operates in Indexed Literal Offset Addressing mode whenever f 95 (5Fh). See Section 29.2.3 “Byte-Oriented and Bit-Oriented Instructions in Indexed Literal Offset Mode” for details. 35h Words: 1 Cycles: 1 Q Cycle Activity: Q1 Decode Example: Q2 Read register ‘f’ IORWF Before Instruction RESULT = W = After Instruction RESULT = W = DS39957B-page 472 00da If ‘a’ is ‘0’, the Access Bank is selected. If ‘a’ is ‘1’, the BSR is used to select the GPR bank. 9Ah BFh 0001 f {,d {,a}} Preliminary Q3 Process Data Q4 Write to destination RESULT, 0, 1 13h 91h 13h 93h 2010 Microchip Technology Inc. PIC18F87K90 FAMILY LFSR Load FSR MOVF Move f Syntax: LFSR f, k Syntax: MOVF Operands: 0f2 0 k 4095 Operands: Operation: k FSRf 0 f 255 d [0,1] a [0,1] Status Affected: None Operation: f dest Status Affected: N, Z Encoding: 1110 1111 1110 0000 00ff k7kkk k11kkk kkkk Description: The 12-bit literal ‘k’ is loaded into the file select register pointed to by ‘f’. Words: 2 Cycles: 2 Q Cycle Activity: Q1 Decode Decode Q2 Read literal ‘k’ MSB Q3 Process Data Read literal ‘k’ LSB Process Data Example: After Instruction FSR2H FSR2L Encoding: Description: Q4 Write literal ‘k’ MSB to FSRfH Write literal ‘k’ to FSRfL 03h ABh 0101 ffff ffff The contents of register ‘f’ are moved to a destination dependent upon the status of ‘d’. If ‘d’ is ‘0’, the result is placed in W. If ‘d’ is ‘1’, the result is placed back in register ‘f’. Location ‘f’ can be anywhere in the 256-byte bank. If ‘a’ is ‘0’ and the extended instruction set is enabled, this instruction operates in Indexed Literal Offset Addressing mode whenever f 95 (5Fh). See Section 29.2.3 “Byte-Oriented and Bit-Oriented Instructions in Indexed Literal Offset Mode” for details. Words: 1 Cycles: 1 Q Cycle Activity: Q1 Decode Example: Q2 Read register ‘f’ MOVF Before Instruction REG W After Instruction REG W 2010 Microchip Technology Inc. 00da If ‘a’ is ‘0’, the Access Bank is selected. If ‘a’ is ‘1’, the BSR is used to select the GPR bank. LFSR 2, 3ABh = = f {,d {,a}} Preliminary Q3 Process Data Q4 Write W REG, 0, 0 = = 22h FFh = = 22h 22h DS39957B-page 473 PIC18F87K90 FAMILY MOVFF Move f to f MOVLB Move Literal to Low Nibble in BSR Syntax: MOVFF fs,fd Syntax: MOVLW k Operands: 0 fs 4095 0 fd 4095 Operands: 0 k 255 Operation: k BSR Operation: (fs) fd Status Affected: None Status Affected: None Encoding: 1st word (source) 2nd word (destin.) Encoding: 1100 1111 Description: ffff ffff ffff ffff ffffs ffffd The contents of source register ‘fs’ are moved to destination register ‘fd’. Location of source ‘fs’ can be anywhere in the 4096-byte data space (000h to FFFh) and location of destination ‘fd’ can also be anywhere from 000h to FFFh. Either source or destination can be W (a useful special situation). MOVFF is particularly useful for transferring a data memory location to a peripheral register (such as the transmit buffer or an I/O port). 2 Cycles: 2 Q Cycle Activity: Q1 Decode Decode Q2 Read register ‘f’ (src) No operation No dummy read Example: MOVFF Before Instruction REG1 REG2 After Instruction REG1 REG2 DS39957B-page 474 Q3 Process Data Q4 No operation No operation Write register ‘f’ (dest) 0001 kkkk kkkk Description: The 8-bit literal ‘k’ is loaded into the Bank Select Register (BSR). The value of BSR<7:4> always remains ‘0’ regardless of the value of k7:k4. Words: 1 Cycles: 1 Q Cycle Activity: Q1 Decode Example: The MOVFF instruction cannot use the PCL, TOSU, TOSH or TOSL as the destination register Words: 0000 Q2 Read literal ‘k’ Q3 Process Data MOVLB 5 Before Instruction BSR Register = After Instruction BSR Register = Q4 Write literal ‘k’ to BSR 02h 05h REG1, REG2 = = 33h 11h = = 33h 33h Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY MOVLW Move Literal to W MOVWF Move W to f Syntax: MOVLW k Syntax: MOVWF Operands: 0 f 255 a [0,1] Operation: (W) f Status Affected: None Operands: 0 k 255 Operation: kW Status Affected: None Encoding: 0000 1110 kkkk kkkk The 8-bit literal ‘k’ is loaded into W. Encoding: Words: 1 Description: Cycles: 1 Description: Q Cycle Activity: Q1 Decode Q2 Read literal ‘k’ Example: After Instruction W = MOVLW Q3 Process Data 0110 111a ffff ffff Move data from W to register ‘f’. Location ‘f’ can be anywhere in the 256-byte bank. If ‘a’ is ‘0’, the Access Bank is selected. If ‘a’ is ‘1’, the BSR is used to select the GPR bank. Q4 Write to W If ‘a’ is ‘0’ and the extended instruction set is enabled, this instruction operates in Indexed Literal Offset Addressing mode whenever f 95 (5Fh). See Section 29.2.3 “Byte-Oriented and Bit-Oriented Instructions in Indexed Literal Offset Mode” for details. 5Ah 5Ah Words: 1 Cycles: 1 Q Cycle Activity: Q1 Decode Example: Q2 Read register ‘f’ MOVWF Before Instruction W = REG = After Instruction W = REG = 2010 Microchip Technology Inc. f {,a} Preliminary Q3 Process Data Q4 Write register ‘f’ REG, 0 4Fh FFh 4Fh 4Fh DS39957B-page 475 PIC18F87K90 FAMILY MULLW Multiply Literal with W MULWF Multiply W with f Syntax: MULLW Syntax: MULWF Operands: 0 f 255 a [0,1] Operation: (W) x (f) PRODH:PRODL Status Affected: None k Operands: 0 k 255 Operation: (W) x k PRODH:PRODL Status Affected: None Encoding: Description: 0000 1101 kkkk kkkk An unsigned multiplication is carried out between the contents of W and the 8-bit literal ‘k’. The 16-bit result is placed in the PRODH:PRODL register pair. PRODH contains the high byte. Encoding: Description: W is unchanged. None of the Status flags are affected. 1 Cycles: 1 Q Cycle Activity: Q1 Decode Before Instruction W PRODH PRODL After Instruction W PRODH PRODL ffff ffff Note that neither Overflow nor Carry is possible in this operation. A Zero result is possible but not detected. MULLW Q3 Process Data 0C4h = = = E2h ? ? = = = E2h ADh 08h Q4 Write registers PRODH: PRODL If ‘a’ is ‘0’ and the extended instruction set is enabled, this instruction operates in Indexed Literal Offset Addressing mode whenever f 95 (5Fh). See Section 29.2.3 “Byte-Oriented and Bit-Oriented Instructions in Indexed Literal Offset Mode” for details. Words: 1 Cycles: 1 Q Cycle Activity: Q1 Decode Q2 Read register ‘f’ Example: Before Instruction W REG PRODH PRODL After Instruction W REG PRODH PRODL DS39957B-page 476 001a If ‘a’ is ‘0’, the Access Bank is selected. If ‘a’ is ‘1’, the BSR is used to select the GPR bank. Q2 Read literal ‘k’ Example: 0000 An unsigned multiplication is carried out between the contents of W and the register file location ‘f’. The 16-bit result is stored in the PRODH:PRODL register pair. PRODH contains the high byte. Both W and ‘f’ are unchanged. None of the Status flags are affected. Note that neither Overflow nor Carry is possible in this operation. A Zero result is possible but not detected. Words: f {,a} Preliminary MULWF Q3 Process Data Q4 Write registers PRODH: PRODL REG, 1 = = = = C4h B5h ? ? = = = = C4h B5h 8Ah 94h 2010 Microchip Technology Inc. PIC18F87K90 FAMILY NEGF Negate f Syntax: NEGF Operands: 0 f 255 a [0,1] f {,a} Operation: (f) + 1 f Status Affected: N, OV, C, DC, Z Encoding: Description: 0110 110a ffff If ‘a’ is ‘0’ and the extended instruction set is enabled, this instruction operates in Indexed Literal Offset Addressing mode whenever f 95 (5Fh). See Section 29.2.3 “Byte-Oriented and Bit-Oriented Instructions in Indexed Literal Offset Mode” for details. 1 1 Q Cycle Activity: Q1 Decode Example: Q2 Read register ‘f’ NEGF Before Instruction REG = After Instruction REG = Syntax: NOP Operands: None Operation: No operation Status Affected: None Q3 Process Data 0000 1111 ffff If ‘a’ is ‘0’, the Access Bank is selected. If ‘a’ is ‘1’, the BSR is used to select the GPR bank. Cycles: No Operation Encoding: Location ‘f’ is negated using two’s complement. The result is placed in the data memory location ‘f’. Words: NOP 0000 xxxx Description: No operation. Words: 1 Cycles: 1 Q Cycle Activity: Q1 Decode Q2 No operation 0000 xxxx Q3 No operation 0000 xxxx Q4 No operation Example: None. Q4 Write register ‘f’ REG, 1 0011 1010 [3Ah] 1100 0110 [C6h] 2010 Microchip Technology Inc. Preliminary DS39957B-page 477 PIC18F87K90 FAMILY POP Pop Top of Return Stack PUSH Push Top of Return Stack Syntax: POP Syntax: PUSH Operands: None Operands: None Operation: (TOS) bit bucket Operation: (PC + 2) TOS Status Affected: None Status Affected: None Encoding: 0000 0000 0000 0110 Encoding: 0000 0000 0000 0101 Description: The TOS value is pulled off the return stack and is discarded. The TOS value then becomes the previous value that was pushed onto the return stack. This instruction is provided to enable the user to properly manage the return stack to incorporate a software stack. Description: The PC + 2 is pushed onto the top of the return stack. The previous TOS value is pushed down on the stack. This instruction allows implementing a software stack by modifying TOS and then pushing it onto the return stack. Words: 1 Words: 1 Cycles: 1 Cycles: 1 Q Cycle Activity: Q1 Decode Q2 No operation Q3 POP TOS value POP GOTO NEW Example: Q4 No operation Example: Before Instruction TOS Stack (1 level down) = = 0031A2h 014332h After Instruction TOS PC = = 014332h NEW DS39957B-page 478 Q Cycle Activity: Q1 Decode Preliminary Q2 PUSH PC + 2 onto return stack Q3 No operation Q4 No operation PUSH Before Instruction TOS PC = = 345Ah 0124h After Instruction PC TOS Stack (1 level down) = = = 0126h 0126h 345Ah 2010 Microchip Technology Inc. PIC18F87K90 FAMILY RCALL Relative Call RESET Reset Syntax: RCALL Syntax: RESET n Operands: -1024 n 1023 Operands: None Operation: (PC) + 2 TOS, (PC) + 2 + 2n PC Operation: Reset all registers and flags that are affected by a MCLR Reset. Status Affected: None Status Affected: All Encoding: Description: 1101 Words: 1 Cycles: 2 Q Cycle Activity: Q1 Decode No operation Example: 1nnn nnnn nnnn Subroutine call with a jump up to 1K from the current location. First, return address (PC + 2) is pushed onto the stack. Then, add the 2’s complement number ‘2n’ to the PC. Since the PC will have incremented to fetch the next instruction, the new address will be PC + 2 + 2n. This instruction is a two-cycle instruction. Q3 Process Data Q4 Write to PC No operation No operation 0000 0000 1111 1111 Description: This instruction provides a way to execute a MCLR Reset in software. Words: 1 Cycles: 1 Q Cycle Activity: Q1 Decode Example: Q2 Read literal ‘n’ PUSH PC to stack No operation HERE Encoding: After Instruction Registers = Flags* = Q2 Start reset Q3 No operation Q4 No operation RESET Reset Value Reset Value RCALL Jump Before Instruction PC = Address (HERE) After Instruction PC = Address (Jump) TOS = Address (HERE + 2) 2010 Microchip Technology Inc. Preliminary DS39957B-page 479 PIC18F87K90 FAMILY RETFIE Return from Interrupt RETLW Return Literal to W Syntax: RETFIE {s} Syntax: RETLW k Operands: s [0,1] Operands: 0 k 255 Operation: (TOS) PC, 1 GIE/GIEH or PEIE/GIEL; if s = 1, (WS) W, (STATUSS) STATUS, (BSRS) BSR, PCLATU, PCLATH are unchanged Operation: k W, (TOS) PC, PCLATU, PCLATH are unchanged Status Affected: None Status Affected: 0000 Description: 0000 0001 1 Cycles: 2 1100 kkkk kkkk Description: W is loaded with the 8-bit literal ‘k’. The program counter is loaded from the top of the stack (the return address). The high address latch (PCLATH) remains unchanged. Words: 1 Cycles: 2 000s Return from interrupt. Stack is popped and Top-of-Stack (TOS) is loaded into the PC. Interrupts are enabled by setting either the high or low-priority global interrupt enable bit. If ‘s’ = 1, the contents of the shadow registers WS, STATUSS and BSRS are loaded into their corresponding registers W, STATUS and BSR. If ‘s’ = 0, no update of these registers occurs. Words: No operation 0000 GIE/GIEH, PEIE/GIEL. Encoding: Q Cycle Activity: Q1 Decode Encoding: Q Cycle Activity: Q1 Decode No operation Q2 Read literal ‘k’ Q3 Process Data No operation No operation Q4 POP PC from stack, write to W No operation Example: Q2 No operation Q3 No operation No operation No operation Example: RETFIE After Interrupt PC W BSR STATUS GIE/GIEH, PEIE/GIEL DS39957B-page 480 Q4 POP PC from stack Set GIEH or GIEL No operation 1 = = = = = TOS WS BSRS STATUSS 1 CALL TABLE ; ; ; ; : TABLE ADDWF PCL ; RETLW k0 ; RETLW k1 ; : : RETLW kn ; Before Instruction W = After Instruction W = Preliminary W contains table offset value W now has table value W = offset Begin table End of table 07h value of kn 2010 Microchip Technology Inc. PIC18F87K90 FAMILY RETURN Return from Subroutine RLCF Rotate Left f through Carry Syntax: RETURN {s} Syntax: RLCF Operands: s [0,1] Operands: Operation: (TOS) PC; if s = 1, (WS) W, (STATUSS) STATUS, (BSRS) BSR, PCLATU, PCLATH are unchanged 0 f 255 d [0,1] a [0,1] Operation: (f<n>) dest<n + 1>, (f<7>) C, (C) dest<0> Status Affected: C, N, Z Status Affected: None Encoding: Description: 0000 1 Cycles: 2 No operation Example: 0000 0001 001s Description: Return from subroutine. The stack is popped and the top of the stack (TOS) is loaded into the program counter. If ‘s’= 1, the contents of the shadow registers WS, STATUSS and BSRS are loaded into their corresponding registers W, STATUS and BSR. If ‘s’ = 0, no update of these registers occurs. Words: Q Cycle Activity: Q1 Decode Encoding: Q2 No operation No operation RETURN After Instruction: PC = TOS Q3 Process Data No operation Q4 POP PC from stack No operation 0011 01da ffff ffff The contents of register ‘f’ are rotated one bit to the left through the Carry flag. If ‘d’ is ‘0’, the result is placed in W. If ‘d’ is ‘1’, the result is stored back in register ‘f’. If ‘a’ is ‘0’, the Access Bank is selected. If ‘a’ is ‘1’, the BSR is used to select the GPR bank. If ‘a’ is ‘0’ and the extended instruction set is enabled, this instruction operates in Indexed Literal Offset Addressing mode whenever f 95 (5Fh). See Section 29.2.3 “Byte-Oriented and Bit-Oriented Instructions in Indexed Literal Offset Mode” for details. register f C Words: 1 Cycles: 1 Q Cycle Activity: Q1 Decode Q2 Read register ‘f’ Example: Before Instruction REG = C = After Instruction REG = W = C = 2010 Microchip Technology Inc. f {,d {,a}} Preliminary RLCF Q3 Process Data Q4 Write to destination REG, 0, 0 1110 0110 0 1110 0110 1100 1100 1 DS39957B-page 481 PIC18F87K90 FAMILY RLNCF Rotate Left f (No Carry) RRCF Rotate Right f through Carry Syntax: RLNCF Syntax: RRCF Operands: 0 f 255 d [0,1] a [0,1] Operands: 0 f 255 d [0,1] a [0,1] Operation: (f<n>) dest<n + 1>, (f<7>) dest<0> Operation: Status Affected: N, Z (f<n>) dest<n – 1>, (f<0>) C, (C) dest<7> Status Affected: C, N, Z Encoding: 0100 Description: f {,d {,a}} 01da ffff ffff The contents of register ‘f’ are rotated one bit to the left. If ‘d’ is ‘0’, the result is placed in W. If ‘d’ is ‘1’, the result is stored back in register ‘f’. Encoding: Description: If ‘a’ is ‘0’, the Access Bank is selected. If ‘a’ is ‘1’, the BSR is used to select the GPR bank. Cycles: 1 Q Cycle Activity: Q1 Decode Before Instruction REG = After Instruction REG = DS39957B-page 482 RLNCF Q3 Process Data Q4 Write to destination Words: 1 Cycles: 1 Q Cycle Activity: Q1 Decode REG, 1, 0 1010 1011 ffff ffff The contents of register ‘f’ are rotated one bit to the right through the Carry flag. If ‘d’ is ‘0’, the result is placed in W. If ‘d’ is ‘1’, the result is placed back in register ‘f’. register f C Q2 Read register ‘f’ Example: 00da If ‘a’ is ‘0’ and the extended instruction set is enabled, this instruction operates in Indexed Literal Offset Addressing mode whenever f 95 (5Fh). See Section 29.2.3 “Byte-Oriented and Bit-Oriented Instructions in Indexed Literal Offset Mode” for details. register f 1 0011 If ‘a’ is ‘0’, the Access Bank is selected. If ‘a’ is ‘1’, the BSR is used to select the GPR bank. If ‘a’ is ‘0’ and the extended instruction set is enabled, this instruction operates in Indexed Literal Offset Addressing mode whenever f 95 (5Fh). See Section 29.2.3 “Byte-Oriented and Bit-Oriented Instructions in Indexed Literal Offset Mode” for details. Words: f {,d {,a}} Example: Q2 Read register ‘f’ RRCF Before Instruction REG = C = After Instruction REG = W = C = 0101 0111 Preliminary Q3 Process Data Q4 Write to destination REG, 0, 0 1110 0110 0 1110 0110 0111 0011 0 2010 Microchip Technology Inc. PIC18F87K90 FAMILY RRNCF Rotate Right f (No Carry) SETF Set f Syntax: RRNCF Syntax: SETF Operands: 0 f 255 d [0,1] a [0,1] Operands: 0 f 255 a [0,1] Operation: FFh f Operation: (f<n>) dest<n – 1>, (f<0>) dest<7> Status Affected: None Status Affected: N, Z Encoding: Description: 0100 f {,d {,a}} 00da Encoding: ffff ffff Description: The contents of register ‘f’ are rotated one bit to the right. If ‘d’ is ‘0’, the result is placed in W. If ‘d’ is ‘1’, the result is placed back in register ‘f’. register f Words: 1 Cycles: 1 Q Cycle Activity: Q1 Decode Example 1: RRNCF Before Instruction REG = After Instruction REG = Example 2: ffff ffff Words: 1 Cycles: 1 Q Cycle Activity: Q1 Decode Q4 Write to destination Q2 Read register ‘f’ SETF Before Instruction REG After Instruction REG Q3 Process Data Q4 Write register ‘f’ REG,1 = 5Ah = FFh REG, 1, 0 1101 0111 1110 1011 RRNCF Before Instruction W = REG = After Instruction W = REG = Q3 Process Data 100a If ‘a’ is ‘0’ and the extended instruction set is enabled, this instruction operates in Indexed Literal Offset Addressing mode whenever f 95 (5Fh). See Section 29.2.3 “Byte-Oriented and Bit-Oriented Instructions in Indexed Literal Offset Mode” for details. Example: Q2 Read register ‘f’ 0110 The contents of the specified register are set to FFh. If ‘a’ is ‘0’, the Access Bank is selected. If ‘a’ is ‘1’, the BSR is used to select the GPR bank. If ‘a’ is ‘0’, the Access Bank will be selected, overriding the BSR value. If ‘a’ is ‘1’, then the bank will be selected as per the BSR value. If ‘a’ is ‘0’ and the extended instruction set is enabled, this instruction operates in Indexed Literal Offset Addressing mode whenever f 95 (5Fh). See Section 29.2.3 “Byte-Oriented and Bit-Oriented Instructions in Indexed Literal Offset Mode” for details. f {,a} REG, 0, 0 ? 1101 0111 1110 1011 1101 0111 2010 Microchip Technology Inc. Preliminary DS39957B-page 483 PIC18F87K90 FAMILY SLEEP Enter Sleep Mode SUBFWB Subtract f from W with Borrow Syntax: SLEEP Syntax: SUBFWB Operands: None Operands: Operation: 00h WDT, 0 WDT postscaler, 1 TO, 0 PD 0 f 255 d [0,1] a [0,1] Operation: (W) – (f) – (C) dest Status Affected: N, OV, C, DC, Z Status Affected: TO, PD Encoding: 0000 Description: Encoding: 0000 0000 0011 Description: The Power-Down status bit (PD) is cleared. The Time-out status bit (TO) is set. The Watchdog Timer and its postscaler are cleared. The processor is put into Sleep mode with the oscillator stopped. Words: 1 Cycles: 1 Q Cycle Activity: Q1 Decode Q2 No operation Example: Q3 Process Data SLEEP Before Instruction TO = ? PD = ? After Instruction 1† TO = PD = 0 † If WDT causes wake-up, this bit is cleared. DS39957B-page 484 0101 f {,d {,a}} 01da ffff ffff Subtract register ‘f’ and Carry flag (borrow) from W (2’s complement method). If ‘d’ is ‘0’, the result is stored in W. If ‘d’ is ‘1’, the result is stored in register ‘f’. If ‘a’ is ‘0’, the Access Bank is selected. If ‘a’ is ‘1’, the BSR is used to select the GPR bank. If ‘a’ is ‘0’ and the extended instruction set is enabled, this instruction operates in Indexed Literal Offset Addressing mode whenever f 95 (5Fh). See Section 29.2.3 “Byte-Oriented and Bit-Oriented Instructions in Indexed Literal Offset Mode” for details. Q4 Go to Sleep Words: 1 Cycles: 1 Q Cycle Activity: Q1 Decode Q2 Read register ‘f’ Q3 Process Data Q4 Write to destination Example 1: SUBFWB REG, 1, 0 Before Instruction REG = 3 W = 2 C = 1 After Instruction REG = FF W = 2 C = 0 Z = 0 N = 1 ; result is negative Example 2: SUBFWB REG, 0, 0 Before Instruction REG = 2 W = 5 C = 1 After Instruction REG = 2 W = 3 C = 1 Z = 0 N = 0 ; result is positive Example 3: SUBFWB REG, 1, 0 Before Instruction REG = 1 W = 2 C = 0 After Instruction REG = 0 W = 2 C = 1 Z = 1 ; result is zero N = 0 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY SUBLW Subtract W from Literal SUBWF Subtract W from f Syntax: SUBLW k Syntax: SUBWF Operands: 0 f 255 d [0,1] a [0,1] Operation: (f) – (W) dest Status Affected: N, OV, C, DC, Z Operands: 0 k 255 Operation: k – (W) W Status Affected: N, OV, C, DC, Z Encoding: 0000 1000 kkkk kkkk Description: W is subtracted from the 8-bit literal ‘k’. The result is placed in W. Words: 1 Cycles: 1 Q Cycle Activity: Q1 Decode Description: Q2 Read literal ‘k’ Example 1: Before Instruction W = C = After Instruction W = C = Z = N = Example 2: Before Instruction W = C = After Instruction W = C = Z = N = Example 3: Before Instruction W = C = After Instruction W = C = Z = N = Encoding: SUBLW Q3 Process Data SUBLW ; result is positive 02h ? 00h 1 1 0 SUBLW ; result is zero 02h 03h ? FFh 0 0 1 ; (2’s complement) ; result is negative 2010 Microchip Technology Inc. ffff ffff Subtract W from register ‘f’ (2’s complement method). If ‘d’ is ‘0’, the result is stored in W. If ‘d’ is ‘1’, the result is stored back in register ‘f’. If ‘a’ is ‘0’ and the extended instruction set is enabled, this instruction operates in Indexed Literal Offset Addressing mode whenever f 95 (5Fh). See Section 29.2.3 “Byte-Oriented and Bit-Oriented Instructions in Indexed Literal Offset Mode” for details. 02h 02h 11da If ‘a’ is ‘0’, the Access Bank is selected. If ‘a’ is ‘1’, the BSR is used to select the GPR bank. Q4 Write to W 01h ? 01h 1 0 0 0101 f {,d {,a}} Words: 1 Cycles: 1 Q Cycle Activity: Q1 Decode Q2 Read register ‘f’ Example 1: SUBWF Before Instruction REG = 3 W = 2 C = ? After Instruction REG = 1 W = 2 C = 1 Z = 0 N = 0 Example 2: SUBWF Before Instruction REG = 2 W = 2 C = ? After Instruction REG = 2 W = 0 C = 1 Z = 1 N = 0 Example 3: SUBWF Before Instruction REG = 1 W = 2 C = ? After Instruction REG = FFh W = 2 C = 0 Z = 0 N = 1 Preliminary Q3 Process Data Q4 Write to destination REG, 1, 0 ; result is positive REG, 0, 0 ; result is zero REG, 1, 0 ;(2’s complement) ; result is negative DS39957B-page 485 PIC18F87K90 FAMILY SUBWFB Subtract W from f with Borrow SWAPF Swap f Syntax: SUBWFB Syntax: SWAPF f {,d {,a}} Operands: 0 f 255 d [0,1] a [0,1] Operands: 0 f 255 d [0,1] a [0,1] Operation: (f) – (W) – (C) dest Operation: Status Affected: N, OV, C, DC, Z (f<3:0>) dest<7:4>, (f<7:4>) dest<3:0> Status Affected: None Encoding: 0101 Description: f {,d {,a}} 10da ffff ffff Subtract W and the Carry flag (borrow) from register ‘f’ (2’s complement method). If ‘d’ is ‘0’, the result is stored in W. If ‘d’ is ‘1’, the result is stored back in register ‘f’. Encoding: Description: If ‘a’ is ‘0’, the Access Bank is selected. If ‘a’ is ‘1’, the BSR is used to select the GPR bank. 1 Cycles: 1 Q Cycle Activity: Q1 Decode Q2 Read register ‘f’ Q3 Process Data Q4 Write to destination Example 1: SUBWFB REG, 1, 0 Before Instruction (0001 1001) REG = 19h W = 0Dh (0000 1101) C = 1 After Instruction (0000 1011) REG = 0Ch W = 0Dh (0000 1101) C = 1 Z = 0 N = 0 ; result is positive Example 2: SUBWFB REG, 0, 0 Before Instruction (0001 1011) REG = 1Bh W = 1Ah (0001 1010) C = 0 After Instruction (0001 1011) REG = 1Bh W = 00h 1 C = Z = 1 ; result is zero N = 0 Example 3: SUBWFB Before Instruction REG = 03h W = 0Eh C = 1 After Instruction REG = F5h W C Z N = = = = DS39957B-page 486 0Eh 0 0 1 10da ffff ffff If ‘a’ is ‘0’, the Access Bank is selected. If ‘a’ is ‘1’, the BSR is used to select the GPR bank. If ‘a’ is ‘0’ and the extended instruction set is enabled, this instruction operates in Indexed Literal Offset Addressing mode whenever f 95 (5Fh). See Section 29.2.3 “Byte-Oriented and Bit-Oriented Instructions in Indexed Literal Offset Mode” for details. Words: 0011 The upper and lower nibbles of register ‘f’ are exchanged. If ‘d’ is ‘0’, the result is placed in W. If ‘d’ is ‘1’, the result is placed in register ‘f’. If ‘a’ is ‘0’ and the extended instruction set is enabled, this instruction operates in Indexed Literal Offset Addressing mode whenever f 95 (5Fh). See Section 29.2.3 “Byte-Oriented and Bit-Oriented Instructions in Indexed Literal Offset Mode” for details. Words: 1 Cycles: 1 Q Cycle Activity: Q1 Decode Example: Q2 Read register ‘f’ SWAPF Before Instruction REG = After Instruction REG = Q3 Process Data Q4 Write to destination REG, 1, 0 53h 35h REG, 1, 0 (0000 0011) (0000 1101) (1111 0100) ; [2’s comp] (0000 1101) ; result is negative Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY TBLRD Table Read TBLRD Table Read (Continued) Syntax: TBLRD ( *; *+; *-; +*) Example 1: TBLRD Operands: None Operation: if TBLRD *, (Prog Mem (TBLPTR)) TABLAT, TBLPTR – No Change; if TBLRD *+, (Prog Mem (TBLPTR)) TABLAT, (TBLPTR) + 1 TBLPTR; if TBLRD *-, (Prog Mem (TBLPTR)) TABLAT, (TBLPTR) – 1 TBLPTR; if TBLRD +*, (TBLPTR) + 1 TBLPTR, (Prog Mem (TBLPTR)) TABLAT Before Instruction TABLAT TBLPTR MEMORY(00A356h) After Instruction TABLAT TBLPTR Example 2: Status Affected: None Encoding: Description: 0000 0000 0000 TBLRD Before Instruction TABLAT TBLPTR MEMORY(01A357h) MEMORY(01A358h) After Instruction TABLAT TBLPTR *+ ; = = = 55h 00A356h 34h = = 34h 00A357h +* ; = = = = AAh 01A357h 12h 34h = = 34h 01A358h 10nn nn=0 * =1 *+ =2 *=3 +* This instruction is used to read the contents of Program Memory (P.M.). To address the program memory, a pointer called Table Pointer (TBLPTR) is used. The TBLPTR (a 21-bit pointer) points to each byte in the program memory. TBLPTR has a 2-Mbyte address range. TBLPTR<0> = 0:Least Significant Byte of Program Memory Word TBLPTR<0> = 1:Most Significant Byte of Program Memory Word The TBLRD instruction can modify the value of TBLPTR as follows: • no change • post-increment • post-decrement • pre-increment Words: 1 Cycles: 2 Q Cycle Activity: Q1 Decode No operation Q2 No operation No operation (Read Program Memory) 2010 Microchip Technology Inc. Q3 No operation No operation Q4 No operation No operation (Write TABLAT) Preliminary DS39957B-page 487 PIC18F87K90 FAMILY TBLWT Table Write TBLWT Table Write (Continued) Syntax: TBLWT ( *; *+; *-; +*) Example 1: TBLWT *+; Operands: None Operation: if TBLWT*, (TABLAT) Holding Register, TBLPTR – No Change; if TBLWT*+, (TABLAT) Holding Register, (TBLPTR) + 1 TBLPTR; if TBLWT*-, (TABLAT) Holding Register, (TBLPTR) – 1 TBLPTR; if TBLWT+*, (TBLPTR) + 1 TBLPTR, (TABLAT) Holding Register Status Affected: Example 2: None Encoding: Description: Before Instruction TABLAT = 55h TBLPTR = 00A356h HOLDING REGISTER (00A356h) = FFh After Instructions (table write completion) TABLAT = 55h TBLPTR = 00A357h HOLDING REGISTER (00A356h) = 55h 0000 0000 0000 11nn nn=0 * =1 *+ =2 *=3 +* This instruction uses the 3 LSBs of TBLPTR to determine which of the 8 holding registers the TABLAT is written to. The holding registers are used to program the contents of Program Memory (P.M.). (Refer to Section 6.0 “Memory Organization” for additional details on programming Flash memory.) TBLWT +*; Before Instruction TABLAT = 34h TBLPTR = 01389Ah HOLDING REGISTER (01389Ah) = FFh HOLDING REGISTER (01389Bh) = FFh After Instruction (table write completion) TABLAT = 34h TBLPTR = 01389Bh HOLDING REGISTER (01389Ah) = FFh HOLDING REGISTER (01389Bh) = 34h The TBLPTR (a 21-bit pointer) points to each byte in the program memory. TBLPTR has a 2-Mbyte address range. The LSb of the TBLPTR selects which byte of the program memory location to access. TBLPTR<0> = 0:Least Significant Byte of Program Memory Word TBLPTR<0> = 1:Most Significant Byte of Program Memory Word The TBLWT instruction can modify the value of TBLPTR as follows: • no change • post-increment • post-decrement • pre-increment Words: 1 Cycles: 2 Q Cycle Activity: Q1 Decode Q2 Q3 Q4 No No No operation operation operation No No No No operation operation operation operation (Read (Write to TABLAT) Holding Register) DS39957B-page 488 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY TSTFSZ Test f, Skip if 0 XORLW Exclusive OR Literal with W Syntax: TSTFSZ f {,a} Syntax: XORLW k Operands: 0 f 255 a [0,1] Operands: 0 k 255 Operation: (W) .XOR. k W Operation: skip if f = 0 Status Affected: N, Z Status Affected: None Encoding: Description: Encoding: 0110 011a ffff ffff If ‘f’ = 0, the next instruction fetched during the current instruction execution is discarded and a NOP is executed, making this a two-cycle instruction. If ‘a’ is ‘0’, the Access Bank is selected. If ‘a’ is ‘1’, the BSR is used to select the GPR bank. If ‘a’ is ‘0’ and the extended instruction set is enabled, this instruction operates in Indexed Literal Offset Addressing mode whenever f 95 (5Fh). See Section 29.2.3 “Byte-Oriented and Bit-Oriented Instructions in Indexed Literal Offset Mode” for details. Words: 1 Cycles: 1(2) Note: 3 cycles if skip and followed by a 2-word instruction. Q Cycle Activity: Q1 Decode Q2 Read register ‘f’ Q3 Process Data Q4 No operation Q1 Q2 Q3 No No No operation operation operation If skip and followed by 2-word instruction: Q1 Q2 Q3 No No No operation operation operation No No No operation operation operation Q4 No operation 0000 1010 kkkk kkkk Description: The contents of W are XORed with the 8-bit literal ‘k’. The result is placed in W. Words: 1 Cycles: 1 Q Cycle Activity: Q1 Decode Q2 Read literal ‘k’ Example: Before Instruction W = After Instruction W = XORLW Q3 Process Data Q4 Write to W 0AFh B5h 1Ah If skip: Example: HERE NZERO ZERO Before Instruction PC After Instruction If CNT PC If CNT PC TSTFSZ : : Q4 No operation No operation CNT, 1 = Address (HERE) = = = 00h, Address (ZERO) 00h, Address (NZERO) 2010 Microchip Technology Inc. Preliminary DS39957B-page 489 PIC18F87K90 FAMILY XORWF Exclusive OR W with f Syntax: XORWF Operands: 0 f 255 d [0,1] a [0,1] Operation: (W) .XOR. (f) dest Status Affected: N, Z Encoding: 0001 Description: f {,d {,a}} 10da ffff ffff Exclusive OR the contents of W with register ‘f’. If ‘d’ is ‘0’, the result is stored in W. If ‘d’ is ‘1’, the result is stored back in the register ‘f’. If ‘a’ is ‘0’, the Access Bank is selected. If ‘a’ is ‘1’, the BSR is used to select the GPR bank. If ‘a’ is ‘0’ and the extended instruction set is enabled, this instruction operates in Indexed Literal Offset Addressing mode whenever f 95 (5Fh). See Section 29.2.3 “Byte-Oriented and Bit-Oriented Instructions in Indexed Literal Offset Mode” for details. Words: 1 Cycles: 1 Q Cycle Activity: Q1 Decode Q2 Read register ‘f’ Example: XORWF Before Instruction REG = W = After Instruction REG = W = DS39957B-page 490 Q3 Process Data Q4 Write to destination REG, 1, 0 AFh B5h 1Ah B5h Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 29.2 Extended Instruction Set A summary of the instructions in the extended instruction set is provided in Table 29-3. Detailed descriptions are provided in Section 29.2.2 “Extended Instruction Set”. The opcode field descriptions in Table 29-1 (page 450) apply to both the standard and extended PIC18 instruction sets. In addition to the standard 75 instructions of the PIC18 instruction set, the PIC18F87K90 family of devices also provides an optional extension to the core CPU functionality. The added features include eight additional instructions that augment Indirect and Indexed Addressing operations and the implementation of Indexed Literal Offset Addressing for many of the standard PIC18 instructions. Note: The additional features of the extended instruction set are enabled by default on unprogrammed devices. Users must properly set or clear the XINST Configuration bit during programming to enable or disable these features. The instructions in the extended set can all be classified as literal operations, which either manipulate the File Select Registers, or use them for Indexed Addressing. Two of the instructions, ADDFSR and SUBFSR, each have an additional special instantiation for using FSR2. These versions (ADDULNK and SUBULNK) allow for automatic return after execution. 29.2.1 EXTENDED INSTRUCTION SYNTAX Most of the extended instructions use indexed arguments, using one of the File Select Registers and some offset to specify a source or destination register. When an argument for an instruction serves as part of Indexed Addressing, it is enclosed in square brackets (“[ ]”). This is done to indicate that the argument is used as an index or offset. The MPASM™ Assembler will flag an error if it determines that an index or offset value is not bracketed. The extended instructions are specifically implemented to optimize re-entrant program code (that is, code that is recursive or that uses a software stack) written in high-level languages, particularly C. Among other things, they allow users working in high-level languages to perform certain operations on data structures more efficiently. These include: When the extended instruction set is enabled, brackets are also used to indicate index arguments in byte-oriented and bit-oriented instructions. This is in addition to other changes in their syntax. For more details, see Section 29.2.3.1 “Extended Instruction Syntax with Standard PIC18 Commands”. • Dynamic allocation and deallocation of software stack space when entering and leaving subroutines • Function Pointer invocation • Software Stack Pointer manipulation • Manipulation of variables located in a software stack TABLE 29-3: The instruction set extension and the Indexed Literal Offset Addressing mode were designed for optimizing applications written in C; the user may likely never use these instructions directly in assembler. The syntax for these commands is provided as a reference for users who may be reviewing code that has been generated by a compiler. Note: In the past, square brackets have been used to denote optional arguments in the PIC18 and earlier instruction sets. In this text and going forward, optional arguments are denoted by braces (“{ }”). EXTENSIONS TO THE PIC18 INSTRUCTION SET Mnemonic, Operands ADDFSR ADDULNK CALLW MOVSF f, k k MOVSS zs, zd PUSHL k SUBFSR SUBULNK f, k k zs, fd Description Cycles Add Literal to FSR Add Literal to FSR2 and Return Call Subroutine using WREG Move zs (source) to 1st word fd (destination) 2nd word Move zs (source) to 1st word zd (destination) 2nd word Store Literal at FSR2, Decrement FSR2 Subtract Literal from FSR Subtract Literal from FSR2 and Return 2010 Microchip Technology Inc. 16-Bit Instruction Word MSb LSb Status Affected 1000 1000 0000 1011 ffff 1011 xxxx 1010 ffkk 11kk 0001 0zzz ffff 1zzz xzzz kkkk kkkk kkkk 0100 zzzz ffff zzzz zzzz kkkk None None None None 1 1110 1110 0000 1110 1111 1110 1111 1110 1 2 1110 1110 1001 1001 ffkk 11kk kkkk kkkk None None 1 2 2 2 2 Preliminary None None DS39957B-page 491 PIC18F87K90 FAMILY 29.2.2 EXTENDED INSTRUCTION SET ADDFSR Add Literal to FSR ADDULNK Add Literal to FSR2 and Return Syntax: Operands: ADDFSR f, k 0 k 63 f [ 0, 1, 2 ] FSR(f) + k FSR(f) None 1110 1000 ffkk Syntax: Operands: Operation: ADDULNK k 0 k 63 FSR2 + k FSR2, (TOS) PC None 1110 1000 11kk Operation: Status Affected: Encoding: Description: Words: Cycles: Q Cycle Activity: Q1 Decode Example: kkkk The 6-bit literal ‘k’ is added to the contents of the FSR specified by ‘f’. 1 1 Q2 Read literal ‘k’ Q3 Process Data Status Affected: Encoding: Description: The instruction takes two cycles to execute; a NOP is performed during the second cycle. Q4 Write to FSR This may be thought of as a special case of the ADDFSR instruction, where f = 3 (binary ‘11’); it operates only on FSR2. 1 2 ADDFSR 2, 23h Before Instruction FSR2 = After Instruction FSR2 = 03FFh 0422h Words: Cycles: Q Cycle Activity: Q1 Decode No Operation Example: Q2 Read literal ‘k’ No Operation Q3 Process Data No Operation Q4 Write to FSR No Operation ADDULNK 23h Before Instruction FSR2 = PC = After Instruction FSR2 = PC = Note: kkkk The 6-bit literal ‘k’ is added to the contents of FSR2. A RETURN is then executed by loading the PC with the TOS. 03FFh 0100h 0422h (TOS) All PIC18 instructions may take an optional label argument preceding the instruction mnemonic for use in symbolic addressing. If a label is used, the instruction format then becomes: {label} instruction argument(s). DS39957B-page 492 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY CALLW Subroutine Call Using WREG MOVSF Move Indexed to f Syntax: CALLW Syntax: MOVSF [zs], fd Operands: None Operands: Operation: (PC + 2) TOS, (W) PCL, (PCLATH) PCH, (PCLATU) PCU 0 zs 127 0 fd 4095 Operation: ((FSR2) + zs) fd Status Affected: None Status Affected: None Encoding: Description 0000 0000 0001 0100 First, the return address (PC + 2) is pushed onto the return stack. Next, the contents of W are written to PCL; the existing value is discarded. Then, the contents of PCLATH and PCLATU are latched into PCH and PCU, respectively. The second cycle is executed as a NOP instruction while the new next instruction is fetched. Encoding: 1st word (source) 2nd word (destin.) Description: Unlike CALL, there is no option to update W, STATUS or BSR. Words: 1 Cycles: 2 Q Cycle Activity: Q1 Decode No operation Example: Q2 Read WREG No operation HERE Before Instruction PC = PCLATH = PCLATU = W = After Instruction PC = TOS = PCLATH = PCLATU = W = Q3 Push PC to stack No operation 0zzz ffff zzzzs ffffd The contents of the source register are moved to destination register ‘fd’. The actual address of the source register is determined by adding the 7-bit literal offset ‘zs’, in the first word, to the value of FSR2. The address of the destination register is specified by the 12-bit literal ‘fd’ in the second word. Both addresses can be anywhere in the 4096-byte data space (000h to FFFh). Q4 No operation No operation If the resultant source address points to an Indirect Addressing register, the value returned will be 00h. Words: 2 Cycles: 2 Q Cycle Activity: Q1 Decode Decode address (HERE) 10h 00h 06h 2010 Microchip Technology Inc. 1011 ffff The MOVSF instruction cannot use the PCL, TOSU, TOSH or TOSL as the destination register. CALLW 001006h address (HERE + 2) 10h 00h 06h 1110 1111 Example: Q2 Q3 Determine Determine source addr source addr No No operation operation No dummy read MOVSF Before Instruction FSR2 Contents of 85h REG2 After Instruction FSR2 Contents of 85h REG2 Preliminary Q4 Read source reg Write register ‘f’ (dest) [05h], REG2 = 80h = = 33h 11h = 80h = = 33h 33h DS39957B-page 493 PIC18F87K90 FAMILY MOVSS Move Indexed to Indexed PUSHL Store Literal at FSR2, Decrement FSR2 Syntax: MOVSS [zs], [zd] Syntax: PUSHL k Operands: 0 zs 127 0 zd 127 Operation: ((FSR2) + zs) ((FSR2) + zd) Status Affected: None Encoding: 1st word (source) 2nd word (dest.) 1110 1111 Description 1011 xxxx 1zzz xzzz zzzzs zzzzd The contents of the source register are moved to the destination register. The addresses of the source and destination registers are determined by adding the 7-bit literal offsets, ‘zs’ or ‘zd’, respectively, to the value of FSR2. Both registers can be located anywhere in the 4096-byte data memory space (000h to FFFh). The MOVSS instruction cannot use the PCL, TOSU, TOSH or TOSL as the destination register. If the resultant source address points to an Indirect Addressing register, the value returned will be 00h. If the resultant destination address points to an Indirect Addressing register, the instruction will execute as a NOP. Words: 2 Cycles: 2 Q Cycle Activity: Q1 Decode Decode Q2 Q3 Determine Determine source addr source addr Determine Determine dest addr dest addr Example: 0k 255 k (FSR2), FSR2 – 1 FSR2 Status Affected: None Encoding: Description: 1111 1010 kkkk kkkk The 8-bit literal ‘k’ is written to the data memory address specified by FSR2. FSR2 is decremented by 1 after the operation. This instruction allows users to push values onto a software stack. Words: 1 Cycles: 1 Q Cycle Activity: Q1 Decode Example: Q2 Read ‘k’ Q3 Process data Q4 Write to destination PUSHL 08h Before Instruction FSR2H:FSR2L Memory (01ECh) = = 01ECh 00h After Instruction FSR2H:FSR2L Memory (01ECh) = = 01EBh 08h Q4 Read source reg Write to dest reg MOVSS [05h], [06h] Before Instruction FSR2 Contents of 85h Contents of 86h After Instruction FSR2 Contents of 85h Contents of 86h DS39957B-page 494 Operands: Operation: = 80h = 33h = 11h = 80h = 33h = 33h Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY SUBFSR Subtract Literal from FSR SUBULNK Subtract Literal from FSR2 and Return Syntax: Operands: SUBFSR f, k 0 k 63 f [ 0, 1, 2 ] FSRf – k FSRf None 1110 1001 Syntax: Operands: Operation: SUBULNK k 0 k 63 FSR2 – k FSR2, (TOS) PC None 1110 1001 Operation: Status Affected: Encoding: Description: Words: Cycles: Q Cycle Activity: Q1 Decode ffkk kkkk The 6-bit literal ‘k’ is subtracted from the contents of the FSR specified by ‘f’. 1 1 Q2 Read register ‘f’ Q3 Process Data Example: SUBFSR 2, 23h Before Instruction FSR2 = 03FFh After Instruction FSR2 = 03DCh Status Affected: Encoding: Description: 11kk kkkk The 6-bit literal ‘k’ is subtracted from the contents of the FSR2. A RETURN is then executed by loading the PC with the TOS. The instruction takes two cycles to execute; a NOP is performed during the second cycle. Q4 Write to destination Words: Cycles: Q Cycle Activity: Q1 Decode No Operation This may be thought of as a special case of the SUBFSR instruction, where f = 3 (binary ‘11’); it operates only on FSR2. 1 2 Q2 Read register ‘f’ No Operation Q3 Process Data No Operation Q4 Write to destination No Operation Example: SUBULNK 23h Before Instruction FSR2 = 03FFh PC = 0100h After Instruction FSR2 = 03DCh PC = (TOS) 2010 Microchip Technology Inc. Preliminary DS39957B-page 495 PIC18F87K90 FAMILY 29.2.3 Note: BYTE-ORIENTED AND BIT-ORIENTED INSTRUCTIONS IN INDEXED LITERAL OFFSET MODE Enabling the PIC18 instruction set extension may cause legacy applications to behave erratically or fail entirely. In addition to eight new commands in the extended set, enabling the extended instruction set also enables Indexed Literal Offset Addressing (Section 6.6.1 “Indexed Addressing with Literal Offset”). This has a significant impact on the way that many commands of the standard PIC18 instruction set are interpreted. When the extended set is disabled, addresses embedded in opcodes are treated as literal memory locations: either as a location in the Access Bank (a = 0) or in a GPR bank designated by the BSR (a = 1). When the extended instruction set is enabled and a = 0, however, a file register argument of 5Fh or less is interpreted as an offset from the pointer value in FSR2 and not as a literal address. For practical purposes, this means that all instructions that use the Access RAM bit as an argument – that is, all byte-oriented and bit-oriented instructions, or almost half of the core PIC18 instructions – may behave differently when the extended instruction set is enabled. When the content of FSR2 is 00h, the boundaries of the Access RAM are essentially remapped to their original values. This may be useful in creating backward compatible code. If this technique is used, it may be necessary to save the value of FSR2 and restore it when moving back and forth between C and assembly routines in order to preserve the Stack Pointer. Users must also keep in mind the syntax requirements of the extended instruction set (see Section 29.2.3.1 “Extended Instruction Syntax with Standard PIC18 Commands”). Although the Indexed Literal Offset mode can be very useful for dynamic stack and pointer manipulation, it can also be very annoying if a simple arithmetic operation is carried out on the wrong register. Users who are accustomed to the PIC18 programming must keep in mind, that when the extended instruction set is enabled, register addresses of 5Fh or less are used for Indexed Literal Offset Addressing. Representative examples of typical byte-oriented and bit-oriented instructions in the Indexed Literal Offset mode are provided on the following page to show how execution is affected. The operand conditions shown in the examples are applicable to all instructions of these types. DS39957B-page 496 29.2.3.1 Extended Instruction Syntax with Standard PIC18 Commands When the extended instruction set is enabled, the file register argument, ‘f’, in the standard byte-oriented and bit-oriented commands is replaced with the literal offset value, ‘k’. As already noted, this occurs only when ‘f’ is less than or equal to 5Fh. When an offset value is used, it must be indicated by square brackets (“[ ]”). As with the extended instructions, the use of brackets indicates to the compiler that the value is to be interpreted as an index or an offset. Omitting the brackets, or using a value greater than 5Fh within the brackets, will generate an error in the MPASM™ Assembler. If the index argument is properly bracketed for Indexed Literal Offset Addressing, the Access RAM argument is never specified; it will automatically be assumed to be ‘0’. This is in contrast to standard operation (extended instruction set disabled), when ‘a’ is set on the basis of the target address. Declaring the Access RAM bit in this mode will also generate an error in the MPASM Assembler. The destination argument, ‘d’, functions as before. In the latest versions of the MPASM Assembler, language support for the extended instruction set must be explicitly invoked. This is done with either the command line option, /y, or the PE directive in the source listing. 29.2.4 CONSIDERATIONS WHEN ENABLING THE EXTENDED INSTRUCTION SET It is important to note that the extensions to the instruction set may not be beneficial to all users. In particular, users who are not writing code that uses a software stack may not benefit from using the extensions to the instruction set. Additionally, the Indexed Literal Offset Addressing mode may create issues with legacy applications written to the PIC18 assembler. This is because instructions in the legacy code may attempt to address registers in the Access Bank below 5Fh. Since these addresses are interpreted as literal offsets to FSR2 when the instruction set extension is enabled, the application may read or write to the wrong data addresses. When porting an application to the PIC18F87K90 family, it is very important to consider the type of code. A large, re-entrant application that is written in C and would benefit from efficient compilation will do well when using the instruction set extensions. Legacy applications that heavily use the Access Bank will most likely not benefit from using the extended instruction set. Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY ADD W to Indexed (Indexed Literal Offset mode) BSF Syntax: ADDWF Syntax: BSF [k], b Operands: 0 k 95 d [0,1] Operands: 0 f 95 0b7 Operation: (W) + ((FSR2) + k) dest Operation: 1 ((FSR2) + k)<b> Status Affected: N, OV, C, DC, Z Status Affected: None ADDWF Encoding: Description: [k] {,d} 0010 01d0 kkkk kkkk The contents of W are added to the contents of the register indicated by FSR2, offset by the value ‘k’. If ‘d’ is ‘0’, the result is stored in W. If ‘d’ is ‘1’, the result is stored back in register ‘f’ (default). Words: 1 Cycles: 1 Q Cycle Activity: Q1 Decode Example: Q2 Read ‘k’ Q3 Process Data ADDWF Before Instruction W OFST FSR2 Contents of 0A2Ch After Instruction W Contents of 0A2Ch Q4 Write to destination Encoding: 17h 2Ch 0A00h = 20h = 37h = 20h 1000 kkkk kkkk Bit ‘b’ of the register indicated by FSR2, offset by the value ‘k’, is set. Words: 1 Cycles: 1 Q Cycle Activity: Q1 Decode Example: Q2 Read register ‘f’ BSF Before Instruction FLAG_OFST FSR2 Contents of 0A0Ah After Instruction Contents of 0A0Ah Q3 Process Data Q4 Write to destination [FLAG_OFST], 7 = = 0Ah 0A00h = 55h = D5h SETF Set Indexed (Indexed Literal Offset mode) Syntax: SETF [k] Operands: 0 k 95 Operation: FFh ((FSR2) + k) Status Affected: None Encoding: 0110 1000 kkkk kkkk Description: The contents of the register indicated by FSR2, offset by ‘k’, are set to FFh. Words: 1 Cycles: 1 Q Cycle Activity: Q1 Decode Example: Q2 Read ‘k’ SETF Before Instruction OFST FSR2 Contents of 0A2Ch After Instruction Contents of 0A2Ch 2010 Microchip Technology Inc. bbb0 Description: [OFST] ,0 = = = Bit Set Indexed (Indexed Literal Offset mode) Preliminary Q3 Process Data Q4 Write register [OFST] = = 2Ch 0A00h = 00h = FFh DS39957B-page 497 PIC18F87K90 FAMILY 29.2.5 SPECIAL CONSIDERATIONS WITH MICROCHIP MPLAB® IDE TOOLS The latest versions of Microchip’s software tools have been designed to fully support the extended instruction set for the PIC18F87K90 family family. This includes the MPLAB C18 C Compiler, MPASM assembly language and MPLAB Integrated Development Environment (IDE). When selecting a target device for software development, MPLAB IDE will automatically set default Configuration bits for that device. The default setting for the XINST Configuration bit is ‘0’, disabling the extended instruction set and Indexed Literal Offset Addressing. For proper execution of applications developed to take advantage of the extended instruction set, XINST must be set during programming. DS39957B-page 498 To develop software for the extended instruction set, the user must enable support for the instructions and the Indexed Addressing mode in their language tool(s). Depending on the environment being used, this may be done in several ways: • A menu option or dialog box within the environment that allows the user to configure the language tool and its settings for the project • A command line option • A directive in the source code These options vary between different compilers, assemblers and development environments. Users are encouraged to review the documentation accompanying their development systems for the appropriate information. Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 30.0 DEVELOPMENT SUPPORT 30.1 The PIC® microcontrollers and dsPIC® digital signal controllers are supported with a full range of software and hardware development tools: • Integrated Development Environment - MPLAB® IDE Software • Compilers/Assemblers/Linkers - MPLAB C Compiler for Various Device Families - HI-TECH C for Various Device Families - MPASMTM Assembler - MPLINKTM Object Linker/ MPLIBTM Object Librarian - MPLAB Assembler/Linker/Librarian for Various Device Families • Simulators - MPLAB SIM Software Simulator • Emulators - MPLAB REAL ICE™ In-Circuit Emulator • In-Circuit Debuggers - MPLAB ICD 3 - PICkit™ 3 Debug Express • Device Programmers - PICkit™ 2 Programmer - MPLAB PM3 Device Programmer • Low-Cost Demonstration/Development Boards, Evaluation Kits, and Starter Kits MPLAB Integrated Development Environment Software The MPLAB IDE software brings an ease of software development previously unseen in the 8/16/32-bit microcontroller market. The MPLAB IDE is a Windows® operating system-based application that contains: • A single graphical interface to all debugging tools - Simulator - Programmer (sold separately) - In-Circuit Emulator (sold separately) - In-Circuit Debugger (sold separately) • A full-featured editor with color-coded context • A multiple project manager • Customizable data windows with direct edit of contents • High-level source code debugging • Mouse over variable inspection • Drag and drop variables from source to watch windows • Extensive on-line help • Integration of select third party tools, such as IAR C Compilers The MPLAB IDE allows you to: • Edit your source files (either C or assembly) • One-touch compile or assemble, and download to emulator and simulator tools (automatically updates all project information) • Debug using: - Source files (C or assembly) - Mixed C and assembly - Machine code MPLAB IDE supports multiple debugging tools in a single development paradigm, from the cost-effective simulators, through low-cost in-circuit debuggers, to full-featured emulators. This eliminates the learning curve when upgrading to tools with increased flexibility and power. 2010 Microchip Technology Inc. Preliminary DS39957B-page 499 PIC18F87K90 FAMILY 30.2 MPLAB C Compilers for Various Device Families The MPLAB C Compiler code development systems are complete ANSI C compilers for Microchip’s PIC18, PIC24 and PIC32 families of microcontrollers and the dsPIC30 and dsPIC33 families of digital signal controllers. These compilers provide powerful integration capabilities, superior code optimization and ease of use. For easy source level debugging, the compilers provide symbol information that is optimized to the MPLAB IDE debugger. 30.3 HI-TECH C for Various Device Families For easy source level debugging, the compilers provide symbol information that is optimized to the MPLAB IDE debugger. The compilers include a macro assembler, linker, preprocessor, and one-step driver, and can run on multiple platforms. MPASM Assembler The MPASM Assembler is a full-featured, universal macro assembler for PIC10/12/16/18 MCUs. The MPASM Assembler generates relocatable object files for the MPLINK Object Linker, Intel® standard HEX files, MAP files to detail memory usage and symbol reference, absolute LST files that contain source lines and generated machine code and COFF files for debugging. The MPASM Assembler features include: MPLINK Object Linker/ MPLIB Object Librarian The MPLINK Object Linker combines relocatable objects created by the MPASM Assembler and the MPLAB C18 C Compiler. It can link relocatable objects from precompiled libraries, using directives from a linker script. The MPLIB Object Librarian manages the creation and modification of library files of precompiled code. When a routine from a library is called from a source file, only the modules that contain that routine will be linked in with the application. This allows large libraries to be used efficiently in many different applications. The object linker/library features include: The HI-TECH C Compiler code development systems are complete ANSI C compilers for Microchip’s PIC family of microcontrollers and the dsPIC family of digital signal controllers. These compilers provide powerful integration capabilities, omniscient code generation and ease of use. 30.4 30.5 • Efficient linking of single libraries instead of many smaller files • Enhanced code maintainability by grouping related modules together • Flexible creation of libraries with easy module listing, replacement, deletion and extraction 30.6 MPLAB Assembler, Linker and Librarian for Various Device Families MPLAB Assembler produces relocatable machine code from symbolic assembly language for PIC24, PIC32 and dsPIC devices. MPLAB C Compiler uses the assembler to produce its object file. The assembler generates relocatable object files that can then be archived or linked with other relocatable object files and archives to create an executable file. Notable features of the assembler include: • • • • • • Support for the entire device instruction set Support for fixed-point and floating-point data Command line interface Rich directive set Flexible macro language MPLAB IDE compatibility • Integration into MPLAB IDE projects • User-defined macros to streamline assembly code • Conditional assembly for multi-purpose source files • Directives that allow complete control over the assembly process DS39957B-page 500 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 30.7 MPLAB SIM Software Simulator 30.9 The MPLAB SIM Software Simulator allows code development in a PC-hosted environment by simulating the PIC MCUs and dsPIC® DSCs on an instruction level. On any given instruction, the data areas can be examined or modified and stimuli can be applied from a comprehensive stimulus controller. Registers can be logged to files for further run-time analysis. The trace buffer and logic analyzer display extend the power of the simulator to record and track program execution, actions on I/O, most peripherals and internal registers. The MPLAB SIM Software Simulator fully supports symbolic debugging using the MPLAB C Compilers, and the MPASM and MPLAB Assemblers. The software simulator offers the flexibility to develop and debug code outside of the hardware laboratory environment, making it an excellent, economical software development tool. 30.8 MPLAB REAL ICE In-Circuit Emulator System MPLAB REAL ICE In-Circuit Emulator System is Microchip’s next generation high-speed emulator for Microchip Flash DSC and MCU devices. It debugs and programs PIC® Flash MCUs and dsPIC® Flash DSCs with the easy-to-use, powerful graphical user interface of the MPLAB Integrated Development Environment (IDE), included with each kit. The emulator is connected to the design engineer’s PC using a high-speed USB 2.0 interface and is connected to the target with either a connector compatible with incircuit debugger systems (RJ11) or with the new highspeed, noise tolerant, Low-Voltage Differential Signal (LVDS) interconnection (CAT5). The emulator is field upgradable through future firmware downloads in MPLAB IDE. In upcoming releases of MPLAB IDE, new devices will be supported, and new features will be added. MPLAB REAL ICE offers significant advantages over competitive emulators including low-cost, full-speed emulation, run-time variable watches, trace analysis, complex breakpoints, a ruggedized probe interface and long (up to three meters) interconnection cables. 2010 Microchip Technology Inc. MPLAB ICD 3 In-Circuit Debugger System MPLAB ICD 3 In-Circuit Debugger System is Microchip's most cost effective high-speed hardware debugger/programmer for Microchip Flash Digital Signal Controller (DSC) and microcontroller (MCU) devices. It debugs and programs PIC® Flash microcontrollers and dsPIC® DSCs with the powerful, yet easyto-use graphical user interface of MPLAB Integrated Development Environment (IDE). The MPLAB ICD 3 In-Circuit Debugger probe is connected to the design engineer's PC using a high-speed USB 2.0 interface and is connected to the target with a connector compatible with the MPLAB ICD 2 or MPLAB REAL ICE systems (RJ-11). MPLAB ICD 3 supports all MPLAB ICD 2 headers. 30.10 PICkit 3 In-Circuit Debugger/ Programmer and PICkit 3 Debug Express The MPLAB PICkit 3 allows debugging and programming of PIC® and dsPIC® Flash microcontrollers at a most affordable price point using the powerful graphical user interface of the MPLAB Integrated Development Environment (IDE). The MPLAB PICkit 3 is connected to the design engineer's PC using a full speed USB interface and can be connected to the target via an Microchip debug (RJ-11) connector (compatible with MPLAB ICD 3 and MPLAB REAL ICE). The connector uses two device I/O pins and the reset line to implement in-circuit debugging and In-Circuit Serial Programming™. The PICkit 3 Debug Express include the PICkit 3, demo board and microcontroller, hookup cables and CDROM with user’s guide, lessons, tutorial, compiler and MPLAB IDE software. Preliminary DS39957B-page 501 PIC18F87K90 FAMILY 30.11 PICkit 2 Development Programmer/Debugger and PICkit 2 Debug Express 30.13 Demonstration/Development Boards, Evaluation Kits, and Starter Kits The PICkit™ 2 Development Programmer/Debugger is a low-cost development tool with an easy to use interface for programming and debugging Microchip’s Flash families of microcontrollers. The full featured Windows® programming interface supports baseline (PIC10F, PIC12F5xx, PIC16F5xx), midrange (PIC12F6xx, PIC16F), PIC18F, PIC24, dsPIC30, dsPIC33, and PIC32 families of 8-bit, 16-bit, and 32-bit microcontrollers, and many Microchip Serial EEPROM products. With Microchip’s powerful MPLAB Integrated Development Environment (IDE) the PICkit™ 2 enables in-circuit debugging on most PIC® microcontrollers. In-Circuit-Debugging runs, halts and single steps the program while the PIC microcontroller is embedded in the application. When halted at a breakpoint, the file registers can be examined and modified. A wide variety of demonstration, development and evaluation boards for various PIC MCUs and dsPIC DSCs allows quick application development on fully functional systems. Most boards include prototyping areas for adding custom circuitry and provide application firmware and source code for examination and modification. The PICkit 2 Debug Express include the PICkit 2, demo board and microcontroller, hookup cables and CDROM with user’s guide, lessons, tutorial, compiler and MPLAB IDE software. 30.12 MPLAB PM3 Device Programmer The MPLAB PM3 Device Programmer is a universal, CE compliant device programmer with programmable voltage verification at VDDMIN and VDDMAX for maximum reliability. It features a large LCD display (128 x 64) for menus and error messages and a modular, detachable socket assembly to support various package types. The ICSP™ cable assembly is included as a standard item. In Stand-Alone mode, the MPLAB PM3 Device Programmer can read, verify and program PIC devices without a PC connection. It can also set code protection in this mode. The MPLAB PM3 connects to the host PC via an RS-232 or USB cable. The MPLAB PM3 has high-speed communications and optimized algorithms for quick programming of large memory devices and incorporates an MMC card for file storage and data applications. DS39957B-page 502 The boards support a variety of features, including LEDs, temperature sensors, switches, speakers, RS-232 interfaces, LCD displays, potentiometers and additional EEPROM memory. The demonstration and development boards can be used in teaching environments, for prototyping custom circuits and for learning about various microcontroller applications. In addition to the PICDEM™ and dsPICDEM™ demonstration/development board series of circuits, Microchip has a line of evaluation kits and demonstration software for analog filter design, KEELOQ® security ICs, CAN, IrDA®, PowerSmart battery management, SEEVAL® evaluation system, Sigma-Delta ADC, flow rate sensing, plus many more. Also available are starter kits that contain everything needed to experience the specified device. This usually includes a single application and debug capability, all on one board. Check the Microchip web page (www.microchip.com) for the complete list of demonstration, development and evaluation kits. Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 31.0 ELECTRICAL CHARACTERISTICS Absolute Maximum Ratings(†) Ambient temperature under bias.............................................................................................................-40°C to +125°C Storage temperature .............................................................................................................................. -65°C to +150°C Voltage on any digital only I/O pin or MCLR with respect to VSS (except VDD) ........................................... -0.3V to 9.0V Voltage on any combined digital and analog pin with respect to VSS (except VDD and MCLR)...... -0.3V to (VDD + 0.3V) Voltage on VDD with respect to VSS (regulator enabled) ............................................................................ -0.3V to 5.5V Voltage on VDD with respect to VSS (regulator disabled) ........................................................................... -0.3V to 3.6V Total power dissipation (Note 1) ..................................................................................................................................1W Maximum current out of VSS pin ...........................................................................................................................300 mA Maximum current into VDD pin ..............................................................................................................................250 mA Maximum output current sunk by PORTA<7:6> and any PORTB and PORTC I/O pins.........................................25 mA Maximum output current sunk by any PORTD, PORTE and PORTJ I/O pins ..........................................................8 mA Maximum output current sunk by PORTA<5:0> and any PORTF, PORTG and PORTH I/O pins ............................2 mA Maximum output current sourced by PORTA<7:6> and any PORTB and PORTC I/O pins ...................................25 mA Maximum output current sourced by any PORTD, PORTE and PORTJ I/O pins .....................................................8 mA Maximum output current sourced by PORTA<5:0> and any PORTF, PORTG and PORTH I/O pins .......................2 mA Maximum current sunk byall ports combined.......................................................................................................200 mA Note 1: Power dissipation is calculated as follows: Pdis = VDD x {IDD – IOH} + {(VDD – VOH) x IOH} + (VOL x IOL) † NOTICE: Stresses above those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress rating only and functional operation of the device at those or any other conditions above those indicated in the operation listings of this specification is not implied. Exposure to maximum rating conditions for extended periods may affect device reliability. 2010 Microchip Technology Inc. Preliminary DS39957B-page 503 PIC18F87K90 FAMILY FIGURE 31-1: VOLTAGE-FREQUENCY GRAPH, REGULATOR ENABLED (INDUSTRIAL)(1) 6V 5.5V Voltage (VDD) 5V PIC18F87K90 Family 4V 3V 3V 1.8V 0 FIGURE 31-2: 4 MHz Frequency 64 MHz VOLTAGE-FREQUENCY GRAPH, REGULATOR DISABLED (INDUSTRIAL)(1,2) 4V 3.75V 3.6V Voltage (VDD) 3.25V PIC18F87K90 Family 3V 2.5V 1.8V 4 MHz Note 1: Frequency 64 MHz When the on-chip voltage regulator is disabled, VDD must be maintained so that VDD 3.6V. DS39957B-page 504 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 31.1 DC Characteristics: Supply Voltage PIC18F87K90 Family (Industrial) PIC18F87K90 Family (Industrial) Param Symbol No. D001 VDD Standard Operating Conditions (unless otherwise stated) Operating temperature -40°C TA +85°C for industrial Characteristic Supply Voltage Min Typ Max Units 1.8 1.8 — — 3.6 5.5 V V VDD – 0.3 — VDD + 0.3 V D001C AVDD Analog Supply Voltage D001D AVSS Analog Ground Potential VSS – 0.3 — VSS + 0.3 V D002 VDR RAM Data Retention Voltage(1) 1.5 — — V D003 VPOR VDD Start Voltage to Ensure Internal Power-on Reset Signal — — 0.7 V D004 SVDD VDD Rise Rate to Ensure Internal Power-on Reset Signal 0.05 — — D005 BVDD Brown-out Reset Voltage (High/Medium/Low-Power mode) BORV<1:0> = 11 BORV<1:0> = 10 BORV<1:0> = 01 BORV<1:0> = 00 1.69 1.88 2.53 2.82 1.8 2.0 2.7 3.0 1.91 2.12 2.86 3.18 Note 1: Conditions ENVREG tied to VSS ENVREG tied to VDD See Section 5.3 “Power-on Reset (POR)” for details V/ms See Section 5.3 “Power-on Reset (POR)” for details This is the limit to which VDD can be lowered in Sleep mode, or during a device Reset, without losing RAM data. 2010 Microchip Technology Inc. Preliminary DS39957B-page 505 PIC18F87K90 FAMILY 31.2 DC Characteristics: PIC18F87K90 Family (Industrial) Param No. Power-Down and Supply Current PIC18F87K90 Family (Industrial) Standard Operating Conditions (unless otherwise stated) Operating temperature -40°C TA +85°C for industrial Device Typ Max Units Conditions 10 500 nA -40°C 20 500 nA +25°C 120 600 nA +60°C 630 1800 nA +85°C 50 700 nA -40°C 60 700 nA +25°C 170 800 nA +60°C 700 2700 nA +85°C 350 1300 nA -40°C 400 1400 nA +25°C Power-Down Current (IPD)(1) All devices All devices All devices Note 1: 2: 3: 4: 5: 6: 550 1500 nA +60°C 1350 4000 nA +85°C VDD = 1.8V(4) (Sleep mode) Regulator Disabled VDD = 3.3V(4) (Sleep mode) Regulator Disabled VDD = 5V(5) (Sleep mode) Regulator Enabled The power-down current in Sleep mode does not depend on the oscillator type. Power-down current is measured with the part in Sleep mode, with all I/O pins in a high-impedance state and tied to VDD or VSS, and all features that add delta current are disabled (such as WDT, SOSC oscillator, BOR, etc.). The supply current is mainly a function of operating voltage, frequency and mode. Other factors, such as I/O pin loading and switching rate, oscillator type and circuit, internal code execution pattern and temperature, also have an impact on the current consumption. The test conditions for all IDD measurements in active operation mode are: OSC1 = external square wave, from rail-to-rail; all I/O pins tri-stated, pulled to VDD; MCLR = VDD; WDT enabled/disabled as specified. Standard, low-cost 32 kHz crystals have an operating temperature range of -10°C to +70°C. Extended temperature crystals are available at a much higher cost. Voltage regulator disabled (ENVREG = 0, tied to VSS, RETEN (CONFIG1L<0>) = 1). Voltage regulator enabled (ENVREG = 1, tied to VDD, SRETEN (WDTCON<4>) = 1 and RETEN (CONFIG1L<0>) = 0). LCD glass is not connected; resistor current is not included. DS39957B-page 506 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 31.2 DC Characteristics: PIC18F87K90 Family (Industrial) Param No. Power-Down and Supply Current PIC18F87K90 Family (Industrial) (Continued) Standard Operating Conditions (unless otherwise stated) Operating temperature -40°C TA +85°C for industrial Device Typ Max Units Conditions 5.3 10 A -40°C 5.5 10 A +25°C 5.5 10 A +85°C 10 15 A -40°C 10 16 A +25°C +85°C Supply Current (IDD)(2,3) All devices All devices All devices All devices All devices All devices All devices All devices All devices Note 1: 2: 3: 4: 5: 6: 11 17 A 70 180 A -40°C 80 185 A +25°C 90 190 A +85°C 410 850 A -40°C 410 800 A +25°C 410 830 A +85°C 680 990 A -40°C 680 960 A +25°C 670 950 A +85°C 760 1400 A -40°C 780 1400 A +25°C 800 1500 A +85°C 760 1300 A -40°C 760 1400 A +25°C 770 1500 A +85°C 1.4 2.5 mA -40°C 1.4 2.5 mA +25°C 1.4 2.5 mA +85°C 1.5 2.7 mA -40°C 1.5 2.7 mA +25°C 1.5 2.7 mA +85°C VDD = 1.8V(4) Regulator Disabled VDD = 3.3V(4) Regulator Disabled FOSC = 31 kHz (RC_RUN mode, LF-INTOSC) VDD = 5V(5) Regulator Enabled VDD = 1.8V(4) Regulator Disabled VDD = 3.3V(4) Regulator Disabled FOSC = 1 MHz (RC_RUN mode, HF-INTOSC) VDD = 5V(5) Regulator Enabled VDD = 1.8V(4) Regulator Disabled VDD = 3.3V(4) Regulator Disabled FOSC = 4 MHz (RC_RUN mode, HF-INTOSC) VDD = 5V(5) Regulator Enabled The power-down current in Sleep mode does not depend on the oscillator type. Power-down current is measured with the part in Sleep mode, with all I/O pins in a high-impedance state and tied to VDD or VSS, and all features that add delta current are disabled (such as WDT, SOSC oscillator, BOR, etc.). The supply current is mainly a function of operating voltage, frequency and mode. Other factors, such as I/O pin loading and switching rate, oscillator type and circuit, internal code execution pattern and temperature, also have an impact on the current consumption. The test conditions for all IDD measurements in active operation mode are: OSC1 = external square wave, from rail-to-rail; all I/O pins tri-stated, pulled to VDD; MCLR = VDD; WDT enabled/disabled as specified. Standard, low-cost 32 kHz crystals have an operating temperature range of -10°C to +70°C. Extended temperature crystals are available at a much higher cost. Voltage regulator disabled (ENVREG = 0, tied to VSS, RETEN (CONFIG1L<0>) = 1). Voltage regulator enabled (ENVREG = 1, tied to VDD, SRETEN (WDTCON<4>) = 1 and RETEN (CONFIG1L<0>) = 0). LCD glass is not connected; resistor current is not included. 2010 Microchip Technology Inc. Preliminary DS39957B-page 507 PIC18F87K90 FAMILY 31.2 DC Characteristics: Standard Operating Conditions (unless otherwise stated) Operating temperature -40°C TA +85°C for industrial PIC18F87K90 Family (Industrial) Param No. Power-Down and Supply Current PIC18F87K90 Family (Industrial) (Continued) Device Typ Max Units Conditions 2.1 5.5 A -40°C 2.1 5.7 A +25°C 2.2 6.0 A +85°C 3.7 7.5 A -40°C 3.9 7.8 A +25°C 3.9 8.5 A +85°C Supply Current (IDD) Cont.(2,3) All devices All devices All devices All devices All devices All devices All devices All devices All devices Note 1: 2: 3: 4: 5: 6: 70 180 A -40°C 80 190 A +25°C 80 200 A +85°C 330 650 A -40°C 330 640 A +25°C 330 630 A +85°C 520 850 A -40°C 520 900 A +25°C 520 850 A +85°C 590 940 A -40°C 600 960 A +25°C 620 990 A +85°C 470 770 A -40°C 470 770 A +25°C 460 760 A +85°C 800 1400 A -40°C 800 1350 A +25°C 790 1300 A +85°C 880 1600 A -40°C 890 1700 A +25°C 910 1800 A +85°C VDD = 1.8V(4) Regulator Disabled VDD = 3.3V(4) Regulator Disabled FOSC = 31 kHz (RC_IDLE mode, LF-INTOSC) VDD = 5V(5) Regulator Enabled VDD = 1.8V(4) Regulator Disabled VDD = 3.3V(4) Regulator Disabled FOSC = 1 MHz (RC_IDLE mode, HF-INTOSC) VDD = 5V(5) Regulator Enabled VDD = 1.8V(4) Regulator Disabled VDD = 3.3V(4) Regulator Disabled FOSC = 4 MHz (RC_IDLE mode, internal HF-INTOSC) VDD = 5V(5) Regulator Enabled The power-down current in Sleep mode does not depend on the oscillator type. Power-down current is measured with the part in Sleep mode, with all I/O pins in a high-impedance state and tied to VDD or VSS, and all features that add delta current are disabled (such as WDT, SOSC oscillator, BOR, etc.). The supply current is mainly a function of operating voltage, frequency and mode. Other factors, such as I/O pin loading and switching rate, oscillator type and circuit, internal code execution pattern and temperature, also have an impact on the current consumption. The test conditions for all IDD measurements in active operation mode are: OSC1 = external square wave, from rail-to-rail; all I/O pins tri-stated, pulled to VDD; MCLR = VDD; WDT enabled/disabled as specified. Standard, low-cost 32 kHz crystals have an operating temperature range of -10°C to +70°C. Extended temperature crystals are available at a much higher cost. Voltage regulator disabled (ENVREG = 0, tied to VSS, RETEN (CONFIG1L<0>) = 1). Voltage regulator enabled (ENVREG = 1, tied to VDD, SRETEN (WDTCON<4>) = 1 and RETEN (CONFIG1L<0>) = 0). LCD glass is not connected; resistor current is not included. DS39957B-page 508 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 31.2 DC Characteristics: PIC18F87K90 Family (Industrial) Param No. Power-Down and Supply Current PIC18F87K90 Family (Industrial) (Continued) Standard Operating Conditions (unless otherwise stated) Operating temperature -40°C TA +85°C for industrial Device Typ Max Units Conditions 130 390 A -40°C 130 390 A +25°C 130 390 A +85°C 270 790 A -40°C 270 790 A +25°C 270 790 A +85°C 430 990 A -40°C 450 980 A +25°C 460 980 A +85°C 430 860 A -40°C 530 900 A +25°C 490 880 A +85°C 850 1750 A -40°C 850 1700 A +25°C 850 1800 A +85°C 1.1 2.7 mA -40°C 1.1 2.6 mA +25°C 1.1 2.6 mA +85°C 12 19 mA -40°C 12 19 mA +25°C 12 19 mA +85°C Supply Current (IDD) Cont.(2,3) All devices All devices All devices All devices All devices All devices All devices All devices Note 1: 2: 3: 4: 5: 6: 13 20 mA -40°C 13 20 mA +25°C 12 20 mA +85°C VDD = 1.8V(4) Regulator Disabled VDD = 3.3V(4) Regulator Disabled FOSC = 1 MHZ (PRI_RUN mode, EC oscillator) VDD = 5V(5) Regulator Enabled VDD = 1.8V(4) Regulator Disabled VDD = 3.3V(4) Regulator Disabled FOSC = 4 MHz (PRI_RUN mode, EC oscillator) VDD = 5V(5) Regulator Enabled VDD = 3.3V(4) Regulator Disabled VDD = 5V(5) Regulator Enabled FOSC = 64 MHZ (PRI_RUN mode, EC oscillator) The power-down current in Sleep mode does not depend on the oscillator type. Power-down current is measured with the part in Sleep mode, with all I/O pins in a high-impedance state and tied to VDD or VSS, and all features that add delta current are disabled (such as WDT, SOSC oscillator, BOR, etc.). The supply current is mainly a function of operating voltage, frequency and mode. Other factors, such as I/O pin loading and switching rate, oscillator type and circuit, internal code execution pattern and temperature, also have an impact on the current consumption. The test conditions for all IDD measurements in active operation mode are: OSC1 = external square wave, from rail-to-rail; all I/O pins tri-stated, pulled to VDD; MCLR = VDD; WDT enabled/disabled as specified. Standard, low-cost 32 kHz crystals have an operating temperature range of -10°C to +70°C. Extended temperature crystals are available at a much higher cost. Voltage regulator disabled (ENVREG = 0, tied to VSS, RETEN (CONFIG1L<0>) = 1). Voltage regulator enabled (ENVREG = 1, tied to VDD, SRETEN (WDTCON<4>) = 1 and RETEN (CONFIG1L<0>) = 0). LCD glass is not connected; resistor current is not included. 2010 Microchip Technology Inc. Preliminary DS39957B-page 509 PIC18F87K90 FAMILY 31.2 DC Characteristics: PIC18F87K90 Family (Industrial) Param No. Power-Down and Supply Current PIC18F87K90 Family (Industrial) (Continued) Standard Operating Conditions (unless otherwise stated) Operating temperature -40°C TA +85°C for industrial Device Typ Max Units Conditions 3.3 5.6 mA -40°C 3.3 5.5 mA +25°C 3.3 5.5 mA +85°C Supply Current (IDD) Cont.(2,3) All devices All devices All devices All devices Note 1: 2: 3: 4: 5: 6: 3.5 5.9 mA -40°C 3.5 5.8 mA +25°C 3.5 5.8 mA +85°C 12 18 mA -40°C 12 18 mA +25°C 12 18 mA +85°C 13 20 mA -40°C 12 20 mA +25°C 12 20 mA +85°C VDD = 3.3V(4) Regulator Disabled VDD = 5V(5) Regulator Enabled VDD = 3.3V(4) Regulator Disabled VDD = 5V(5) Regulator Enabled FOSC = 16 MHZ, (PRI_RUN mode, 4 MHz EC oscillator with PLL) FOSC = 64 MHZ, (PRI_RUN mode, 16 MHz EC oscillator with PLL) The power-down current in Sleep mode does not depend on the oscillator type. Power-down current is measured with the part in Sleep mode, with all I/O pins in a high-impedance state and tied to VDD or VSS, and all features that add delta current are disabled (such as WDT, SOSC oscillator, BOR, etc.). The supply current is mainly a function of operating voltage, frequency and mode. Other factors, such as I/O pin loading and switching rate, oscillator type and circuit, internal code execution pattern and temperature, also have an impact on the current consumption. The test conditions for all IDD measurements in active operation mode are: OSC1 = external square wave, from rail-to-rail; all I/O pins tri-stated, pulled to VDD; MCLR = VDD; WDT enabled/disabled as specified. Standard, low-cost 32 kHz crystals have an operating temperature range of -10°C to +70°C. Extended temperature crystals are available at a much higher cost. Voltage regulator disabled (ENVREG = 0, tied to VSS, RETEN (CONFIG1L<0>) = 1). Voltage regulator enabled (ENVREG = 1, tied to VDD, SRETEN (WDTCON<4>) = 1 and RETEN (CONFIG1L<0>) = 0). LCD glass is not connected; resistor current is not included. DS39957B-page 510 Preliminary 2010 Microchip Technology Inc. PIC18F87K90 FAMILY 31.2 DC Characteristics: PIC18F87K90 Family (Industrial) Param No. Power-Down and Supply Current PIC18F87K90 Family (Industrial) (Continued) Standard Operating Conditions (unless otherwise stated) Operating temperature -40°C TA +85°C for industrial Device Typ Max Units Conditions 42 73 A -40°C 42 73 A +25°C +85°C Supply Current (IDD) Cont.(2,3) All devices All devices All devices All devices All devices All devices All devices All devices Note 1: 2: 3: 4: 5: 6: 43 74 A 110 190 A -40°C 110 195 A +25°C +85°C 110 195 A 280 450 A -40°C 290 440 A +25°C 300 460 A +85°C 160 360 A -40°C 160 360 A +25°C 170 370 A +85°C 330 650 A -40°C 340 660 A +25°C 340 660 A +85°C 510 900 A -40°C 520 950 A +25°C 540 990 A +85°C 4.7 9 mA -40°C 4.8 9 mA +25°C 4.8 9 mA +85°C 5.1 11 mA -40°C 5.1 11 mA +25°C 5.2 12 mA +85°C VDD = 1.8V(4) Regulator Disabled VDD = 3.3V(4) Regulator Disabled FOSC = 1 MHz (PRI_IDLE mode, EC oscillator) VDD = 5V(5) Regulator Enabled VDD = 1.8V(4) Regulator Disabled VDD = 3.3V(4) Regulator Disabled FOSC = 4 MHz (PRI_IDLE mode, EC oscillator) VDD = 5V(5) Regulator Enabled VDD = 3.3V(4) Regulator Disabled VDD = 5V(5) Regulator Enabled FOSC = 64 MHz (PRI_IDLE mode, EC oscillator) The power-down current in Sleep mode does not depend on the oscillator type. Power-down current is measured with the part in Sleep mode, with all I/O pins in a high-impedance state and tied to VDD or VSS, and all features that add delta current are disabled (such as WDT, SOSC oscillator, BOR, etc.). The supply current is mainly a function of operating voltage, frequency and mode. Other factors, such as I/O pin loading and switching rate, oscillator type and circuit, internal code execution pattern and temperature, also have an impact on the current consumption. The test conditions for all IDD measurements in active operation mode are: OSC1 = external square wave, from rail-to-rail; all I/O pins tri-stated, pulled to VDD; MCLR = VDD; WDT enabled/disabled as specified. Standard, low-cost 32 kHz crystals have an operating temperature range of -10°C to +70°C. Extended temperature crystals are available at a much higher cost. Voltage regulator disabled (ENVREG = 0, tied to VSS, RETEN (CONFIG1L<0>) = 1). Voltage regulator enabled (ENVREG = 1, tied to VDD, SRETEN (WDTCON<4>) = 1 and RETEN (CONFIG1L<0>) = 0). LCD glass is not connected; resistor current is not included. 2010 Microchip Technology Inc. Preliminary DS39957B-page 511 PIC18F87K90 FAMILY 31.2 DC Characteristics: PIC18F87K90 Family (Industrial) Param No. Power-Down and Supply Current PIC18F87K90 Family (Industrial) (Continued) Standard Operating Conditions (unless otherwise stated) Operating temperature -40°C TA +85°C for industrial Device Typ Max Units Conditions 3.7 8.5 µA -40°C 5.4 10 µA +25°C 6.60 13 µA +85°C 8.7 18 µA -40°C 10 20 µA +25°C +85°C Supply Current (IDD) Cont.(2,3) All devices All devices All devices All devices All devices All devices Note 1: 2: 3: 4: 5: 6: 12 23 µA 60 150 µA -40°C 90 190 µA +25°C 100 240 µA +85°C 1.2 4 µA -40°C 1.7 5 µA +25°C 2.6 6 µA +85°C 1.6 7 µA -40°C 2.8 9 µA +25°C 4.1 10 µA +85°C 60 160 µA -40°C 80 180 µA +25°