PIC16C717/770/771 18/20-Pin, 8-Bit CMOS Microcontrollers with 10/12-Bit A/D Microcontroller Core Features: Pin Diagram * High-performance RISC CPU * Only 35 single word instructions to learn * All single cycle instructions except for program branches which are two cycle * Operating speed: DC - 20 MHz clock input DC - 200 ns instruction cycle 20-Pin PDIP, SOIC, SSOP 1 20 RB3/CCP1/P1A 2 19 RB2/SCK/SCL RA4/T0CKI 3 18 RA7/OSC1/CLKIN RA5/MCLR/VPP 4 17 RA6/OSC2/CLKOUT VSS 5 16 VDD AVSS 6 15 AVDD RA2/AN2/VREF-/VRL 7 14 RB7/T1OSI/P1D RA3/AN3/VREF+/VRH 8 13 RB6/T1OSO/T1CKI/P1C RB0/AN4/INT 9 12 RB5/SDO/P1B RB1/AN5/SS 10 11 RB4/SDI/SDA Memory Device A/D A/D Program Data Pins Resolution Channels x14 x8 PIC16C717 2K 256 18, 20 10 bits 6 PIC16C770 2K 256 20 12 bits 6 PIC16C771 4K 256 20 12 bits 6 * Interrupt capability (up to 10 internal/external interrupt sources) * Eight level deep hardware stack * Direct, indirect and relative addressing modes * Power-on Reset (POR) * Power-up Timer (PWRT) and Oscillator Start-up Timer (OST) * Watchdog Timer (WDT) with its own on-chip RC oscillator for reliable operation * Selectable oscillator options: - INTRC - Internal RC, dual speed (4MHz and 37KHz) dynamically switchable for power savings - ER - External resistor, dual speed (user selectable frequency and 37KHz) dynamically switchable for power savings - EC - External clock - HS - High speed crystal/resonator - XT - Crystal/resonator - LP - Low power crystal * Low-power, high-speed CMOS EPROM technology * In-Circuit Serial ProgrammingTM (ISCP) * Wide operating voltage range: 2.5V to 5.5V * 15 I/O pins with individual control for: - Direction (15 pins) - Digital/Analog input (6 pins) - PORTB interrupt on change (8 pins) - PORTB weak pull-up (8 pins) - High voltage open drain (1 pin) * Commercial and Industrial temperature ranges * Low-power consumption: - < 2 mA @ 5V, 4 MHz - 22.5 A typical @ 3V, 32 kHz - < 1 A typical standby current 1999 Microchip Technology Inc. PIC16C770/771 RA0/AN0 RA1/AN1/LVDIN Peripheral Features: * Timer0: 8-bit timer/counter with 8-bit prescaler * Timer1: 16-bit timer/counter with prescaler, can be incremented during sleep via external crystal/clock * Timer2: 8-bit timer/counter with 8-bit period register, prescaler and postscaler * Enhanced Capture, Compare, PWM (ECCP) module - Capture is 16 bit, max. resolution is 12.5 ns - Compare is 16 bit, max. resolution is 200 ns - PWM max. resolution is 10 bit - Enhanced PWM: - Single, Half-Bridge and Full-Bridge output modes - Digitally programmable deadband delay * Analog-to-Digital converter: - PIC16C770/771 12-bit resolution - PIC16C717 10-bit resolution * On-chip absolute bandgap voltage reference generator * Programmable Brown-out Reset (PBOR) circuitry * Programmable Low-Voltage Detection (PLVD) circuitry * Master Synchronous Serial Port (MSSP) with two modes of operation: - 3-wire SPITM (supports all 4 SPI modes) - I2CTM compatible including master mode support * Program Memory Read (PMR) capability for lookup table, character string storage and checksum calculation purposes Advanced Information DS41120A-page 1 PIC16C717/770/771 Pin Diagrams 18-Pin PDIP, SOIC 20-Pin SSOP 1 18 RB3/CCP1/P1A 2 17 RB2/SCK/SCL RA4/T0CKI 3 16 RA7/OSC1/CLKIN 4 VSS 5 RA2/AN2/VREF-/VRL 6 15 RA6/OSC2/CLKOUT 14 VDD 13 RA0/AN0 1 20 RB3/CCP1/P1A RA1/AN1/LVDIN 2 19 RB2/SCK/SCL RA4/T0CKI 3 18 RA7/OSC1/CLKIN RA5/MCLR/VPP 4 17 RA6/OSC2/CLKOUT VSS(1) 5 16 VDD(2) VSS(1) 6 15 VDD(2) RA2/AN2/VREF-/VRL 7 14 RB7/T1OSI/P1D RA3/AN3/VREF+/VRH 8 13 RB6/T1OSO/T1CKI/P1C RB0/AN4/INT 9 12 RB5/SDO/P1B RB1/AN5/SS 10 11 RB4/SDI/SDA RB7/T1OSI/P1D RA3/AN3/VREF+/VRH 7 12 RB6/T1OSO/T1CKI/P1C RB0/AN4/INT 8 11 RB5/SDO/P1B RB1/AN5/SS 9 10 RB4/SDI/SDA PIC16C717 RA5/MCLR/VPP PIC16C717 RA0/AN0 RA1/AN1/LVDIN Note 1: VSS pins 5 and 6 must be tied together. 2: VDD pins 15 and 16 must be tied together. Key Features PICmicroTM Mid-Range Reference Manual (DS33023) PIC16C717 PIC16C770 PIC16C771 Operating Frequency DC - 20 MHz DC - 20 MHz DC - 20 MHz Resets (and Delays) POR, BOR, MCLR, WDT (PWRT, OST) POR, BOR, MCLR, WDT (PWRT, OST) POR, BOR, MCLR, WDT (PWRT, OST) Program Memory (14-bit words) 2K 2K 4K Data Memory (bytes) 256 256 256 Interrupts 10 10 10 I/O Ports Ports A,B Ports A,B Ports A,B Timers 3 3 3 Enhanced Capture/Compare/PWM (ECCP) modules 1 1 1 Serial Communications MSSP MSSP MSSP 12-bit Analog-to-Digital Module 6 input channels 6 input channels 10-bit Analog-to-Digital Module 6 input channels Instruction Set 35 Instructions 35 Instructions 35 Instructions DS41120A-page 2 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 Table of Contents 1.0 Device Overview ................................................................................................................................................... 5 2.0 Memory Organization.......................................................................................................................................... 11 3.0 I/O Ports.............................................................................................................................................................. 27 4.0 Program Memory Read (PMR) ........................................................................................................................... 43 5.0 Timer0 Module .................................................................................................................................................... 47 6.0 Timer1 Module .................................................................................................................................................... 49 7.0 Timer2 Module .................................................................................................................................................... 53 8.0 Enhanced Capture/Compare/PWM(ECCP) Modules ......................................................................................... 55 9.0 Master Synchronous Serial Port (MSSP) Module............................................................................................... 67 10.0 Voltage Reference Module and Low-voltage Detect......................................................................................... 109 11.0 Analog-to-Digital Converter (A/D) Module ........................................................................................................ 113 12.0 Special Features of the CPU ............................................................................................................................ 125 13.0 Instruction Set Summary................................................................................................................................... 141 14.0 Development Support ....................................................................................................................................... 149 15.0 Electrical Characteristics................................................................................................................................... 155 16.0 DC and AC Characteristics Graphs and Tables ............................................................................................... 177 17.0 Packaging Information ...................................................................................................................................... 179 Revision History ........................................................................................................................................................ 189 Device Differences ..................................................................................................................................................... 189 Index .......................................................................................................................................................................... 191 On-Line Support.......................................................................................................................................................... 197 Reader Response ....................................................................................................................................................... 198 PIC16C717/770/771 Product Identification System .................................................................................................... 199 To Our Valued Customers 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. New Customer Notification System Register on our web site (www.microchip.com/cn) to receive the most current information on our products. Errata An errata sheet may exist for current devices, describing minor operational differences (from the data sheet) and recommended workarounds. 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) * The Microchip Corporate Literature Center; U.S. FAX: (480) 786-7277 When contacting a sales office or the literature center, please specify which device, revision of silicon and data sheet (include literature number) you are using. Corrections to this Data Sheet We constantly strive to improve the quality of all our products and documentation. We have spent a great deal of time to ensure that this document is correct. However, we realize that we may have missed a few things. If you find any information that is missing or appears in error, please: * Fill out and mail in the reader response form in the back of this data sheet. * E-mail us at webmaster@microchip.com. We appreciate your assistance in making this a better document. 1999 Microchip Technology Inc. Advanced Information DS41120A-page 3 PIC16C717/770/771 NOTES: DS41120A-page 4 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 1.0 DEVICE OVERVIEW There are three devices (PIC16C717, PIC16C770 and PIC16C771) covered by this datasheet. The PIC16C717 device comes in 18/20-pin packages and the PIC16C770/771 devices come in 20-pin packages. This document contains device-specific information. Additional information may be found in the PICmicroTM Mid-Range Reference Manual, (DS33023), which may be obtained from your local Microchip Sales Representative or downloaded from the Microchip website. The Reference Manual should be considered a complementary document to this data sheet, and is highly recommended reading for a better understanding of the device architecture and operation of the peripheral modules. FIGURE 1-1: The following two figures are device block diagrams of the PIC16C717 and the PIC16C770/771. PIC16C717 BLOCK DIAGRAM 13 EPROM Program Memory 2K x 14 Program Bus 14 8 Data Bus Program Counter Program Memory Read (PMR) RAM Addr(1) 9 Addr MUX Instruction reg 7 8 PORTB Indirect Addr FSR reg STATUS reg 8 Internal 4MHz, 37KHz and ER mode 3 Instruction Decode & Control OSC1/CLKIN OSC2/CLKOUT RA0/AN0 RA1/AN1/LVDIN RA2/AN2/VREF-/VRL RA3/AN3/VREF+/VRH RA4/T0CKI RA5/MCLR/VPP RA6/OSC2/CLKOUT RA7/OSC1/CLKIN RAM File Registers 256 x 8 8 Level Stack (13-bit) Direct Addr PORTA RB0/AN4/INT RB1/AN5/SS RB2/SCK/SCL RB3/CCP1/P1A RB4/SDI/SDA RB5/SDO/P1B RB6/T1OSO/T1CKI/P1C RB7/T1OSI/P1O MUX Power-up Timer Timing Generation Oscillator Start-up Timer VDD, VSS Power-on Reset ALU 8 W reg Watchdog Timer Brown-out Reset 10-bit ADC Bandgap Reference Low-voltage Detect Timer0 Timer1 Timer2 Enhanced CCP (ECCP1) Master Synchronous Serial Port (MSSP) Note 1: Higher order bits are from the STATUS register. 1999 Microchip Technology Inc. Advanced Information DS41120A-page 5 PIC16C717/770/771 FIGURE 1-2: PIC16C770/771 BLOCK DIAGRAM 13 8 Data Bus Program Counter PORTA RA0/AN0 RA1/AN1/LVDIN RA2/AN2/VREF-/VRL RA3/AN3/VREF+/VRH RA4/T0CKI RA5/MCLR/VPP RA6/OSC2/CLKOUT RA7/OSC1/CLKIN EPROM Program Memory(2) Program Bus 14 RAM File Registers 256 x 8 8 Level Stack (13-bit) Program Memory Read (PMR) RAM Addr(1) 9 Addr MUX Instruction reg Direct Addr 7 8 PORTB Indirect Addr RB0/AN4/INT RB1/AN5/SS RB2/SCK/SCL RB3/CCP1/P1A RB4/SDI/SDA RB5/SDO/P1B RB6/T1OSO/T1CKI/P1C RB7/T1OSI/P1O FSR reg STATUS reg 8 Internal 4MHz, 37KHz and ER mode 3 Instruction Decode & Control OSC1/CLKIN OSC2/CLKOUT MUX Power-up Timer Timing Generation Oscillator Start-up Timer VDD, VSS Power-on Reset ALU 8 W reg Watchdog Timer Brown-out Reset AVDD AVSS 12-bit ADC Bandgap Reference Low-voltage Detect Timer0 Timer1 Timer2 Enhanced CCP (ECCP1) Master Synchronous Serial Port (MSSP) Note 1: Higher order bits are from the STATUS register. 2: Program memory for PIC16C770 is 2K x 14. Program memory for PIC16C771 is 4K x 14. DS41120A-page 6 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 TABLE 1-1: PIC16C770/771 PINOUT DESCRIPTION Name RA0/AN0 RA1/AN1/LVDIN RA2/AN2/VREF-/VRL Input Type Output Type RA0 ST CMOS AN0 AN Function ST AN1 AN A/D input LVDIN AN LVD input reference RA2 ST AN2 AN VREF- AN RA3 RA5/MCLR/VPP RA6/OSC2/CLKOUT RA7/OSC1/CLKIN RB0/AN4/INT RB1/AN5/SS RB2/SCK/SCL RB3/CCP1/P1A ST Note 1: Bi-directional I/O A/D input Negative analog reference input CMOS Internal voltage reference low output Bi-directional I/O AN3 AN A/D input AN Positive analog reference input AN Internal voltage reference high output OD Bi-directional I/O RA4 ST T0CKI ST TMR0 clock input Input port RA5 ST MCLR ST VPP Power RA6 ST Master clear Programming voltage CMOS Bi-directional I/O OSC2 XTAL Crystal/resonator CLKOUT CMOS RA7 ST OSC1 XTAL CLKIN ST RB0 TTL AN4 AN INT ST RB1 TTL AN5 AN CMOS FOSC/4 output Bi-directional I/O Crystal/resonator External clock input/ER resistor connection CMOS Bi-directional I/O(1) A/D input Interrupt input CMOS Bi-directional I/O(1) A/D input SS ST RB2 TTL CMOS SCK ST CMOS Serial clock I/O for SPI SCL ST OD Serial clock I/O for I2C RB3 TTL CMOS CCP1 ST RB4 RB5/SDO/P1B CMOS Bi-directional I/O VREF+ P1A RB4/SDI/SDA CMOS AN VRH RA4/T0CKI Bi-directional I/O A/D input RA1 VRL RA3/AN3/VREF+/VRH Description TTL SSP slave select input CMOS Capture 1 input/Compare 1 output PWM P1A output CMOS Bi-directional input(1) Serial data I/O for I2C SDI ST ST OD RB5 ST CMOS P1B Bit programmable pull-ups. 1999 Microchip Technology Inc. Bi-directional input(1) CMOS SDA SDO Bi-directional input(1) Serial data in for SPI Bi-directional I/O(1) CMOS Serial data out for SPI CMOS PWM P1B output Advanced Information DS41120A-page 7 PIC16C717/770/771 TABLE 1-1: PIC16C770/771 PINOUT DESCRIPTION (CONTINUED) Name RB6/T1OSO/T1CKI/P1C Function Input Type Output Type RB6 TTL CMOS Bi-directional I/O(1) XTAL Crystal/Resonator T1OSO T1CKI ST P1C RB7/T1OSI/P1D RB7 TTL T1OSI XTAL P1D Description TMR1 clock input CMOS PWM P1C output CMOS Bi-directional I/O(1) TMR1 crystal/resonator CMOS PWM P1D output VSS VSS Power Ground reference for logic and I/O pins VDD VDD Power Positive supply for logic and I/O pins AVSS AVSS Power Ground reference for analog Power Positive supply for analog AVDD AVDD Note 1: Bit programmable pull-ups. DS41120A-page 8 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 TABLE 1-2: PIC16C717 PINOUT DESCRIPTION Name RA0/AN0 RA1/AN1/LVDIN RA2/AN2/VREF-/VRL Input Type Output Type RA0 ST CMOS AN0 AN Function ST AN1 AN A/D input reference LVDIN AN LVD input reference RA2 ST AN2 AN VREF- AN RA3 RA5/MCLR/VPP RA6/OSC2/CLKOUT RA7/OSC1/CLKIN RB0/AN4/INT RB1/AN5/SS RB2/SCK/SCL RB3/CCP1/P1A ST Bi-directional I/O A/D input Negative analog reference input CMOS Internal voltage reference low output Bi-directional I/O AN3 AN A/D input AN Positive analog reference high output RA4 ST T0CKI ST AN Internal voltage reference high output OD Bi-directional I/O TMR0 clock input RA5 ST Input port MCLR ST Master Clear VPP Power RA6 ST Programming Voltage CMOS Bi-directional I/O OSC2 XTAL Crystal/Resonator CLKOUT CMOS FOSC/4 output CMOS Bi-directional I/O RA7 ST OSC1 XTAL CLKIN ST RB0 TTL AN4 AN INT ST RB1 TTL AN5 AN Crystal/Resonator External clock input/ER resistor connection CMOS Bi-directional I/O(1) A/D input Interrupt input CMOS Bi-directional I/O(1) A/D input SS ST RB2 TTL CMOS SCK ST CMOS Serial clock I/O for SPI SCL ST OD Serial clock I/O for I2C RB3 TTL CMOS CCP1 ST RB4 TTL SSP slave select input Bi-directional input(1) Bi-directional input(1) CMOS Capture 1 input/Compare 1 output CMOS PWM P1A output CMOS Bi-directional input(1) Serial data I/O for I2C SDI ST SDA ST OD RB5 ST CMOS Bi-directional I/O(1) CMOS Serial data out for SPI CMOS PWM P1B output RB4/SDI/SDA Note 1: CMOS Bi-directional I/O VREF+ P1A RB5/SDO/P1B CMOS AN VRH RA4/T0CKI Bi-directional I/O A/D input RA1 VRL RA3/AN3/VREF+/VRH Description SDO P1B Bit programmable pull-ups. 1999 Microchip Technology Inc. Serial data in for SPI Advanced Information DS41120A-page 9 PIC16C717/770/771 TABLE 1-2: PIC16C717 PINOUT DESCRIPTION (CONTINUED) Name RB6/T1OSO/T1CKI/P1C Function Input Type Output Type RB6 TTL CMOS T1OSO T1CKI XTAL ST P1C RB7/T1OSI/P1D RB7 TTL T1OSI XTAL P1D VSS VSS VDD VDD Note 1: Bit programmable pull-ups. DS41120A-page 10 Description Bi-directional I/O(1) TMR1 Crystal/Resonator TMR1 Clock input CMOS PWM P1C output CMOS Bi-directional I/O(1) TMR1 Crystal/Resonator CMOS PWM P1D output Power Ground Power Positive Supply Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 2.0 MEMORY ORGANIZATION FIGURE 2-2: There are two memory blocks in each of these PICmicro (R) microcontrollers. Each block (Program Memory and Data Memory) has its own bus, so that concurrent access can occur. PC<12:0> Additional information on device memory may be found in the PICmicro Mid-Range Reference Manual, (DS33023). 2.1 PROGRAM MEMORY MAP AND STACK OF THE PIC16C771 CALL, RETURN RETFIE, RETLW 13 Stack Level 1 Program Memory Organization Stack Level 2 The PIC16C717/770/771 devices have a 13-bit program counter capable of addressing an 8K x 14 program memory space. The PIC16C717 and the PIC16C770 have 2K x 14 words of program memory. The PIC16C771 has 4K x 14 words of program memory. Accessing a location above the physically implemented address will cause a wraparound. Stack Level 8 Reset Vector 0000h Interrupt Vector 0004h 0005h The reset vector is at 0000h and the interrupt vector is at 0004h. FIGURE 2-1: PROGRAM MEMORY MAP AND STACK OF THE PIC16C717 AND PIC16C770 On-chip Program Memory Page 0 07FFh 0800h Page 1 0FFFh 1000h PC<12:0> CALL, RETURN RETFIE, RETLW 13 Stack Level 1 3FFFh Stack Level 2 2.2 Data Memory Organization Stack Level 8 Reset Vector Interrupt Vector On-chip Program Memory 0000h 0004h 0005h Page 0 07FFh The data memory is partitioned into multiple banks, which contain the General Purpose Registers and the Special Function Registers. Bits RP1 and RP0 are the bank select bits. RP1 RP0 = 00 = 01 = 10 = 11 Bank0 Bank1 Bank2 Bank3 (STATUS<6:5>) Each bank extends up to 7Fh (128 bytes). The lower locations of each bank are reserved for the Special Function Registers. Above the Special Function Registers are General Purpose Registers, implemented as static RAM. All implemented banks contain special function registers. Some frequently used special function registers from one bank are mirrored in another bank for code reduction and quicker access. 3FFFh 2.2.1 GENERAL PURPOSE REGISTER FILE The register file can be accessed either directly, or indirectly, through the File Select Register FSR. 1999 Microchip Technology Inc. Advanced Information DS41120A-page 11 PIC16C717/770/771 FIGURE 2-3: REGISTER FILE MAP File Address Indirect addr.(*) TMR0 PCL STATUS FSR PORTA PORTB PCLATH INTCON PIR1 PIR2 TMR1L TMR1H T1CON TMR2 T2CON SSPBUF SSPCON CCPR1L CCPR1H CCP1CON ADRESH ADCON0 00h 01h 02h 03h 04h 05h 06h 07h 08h 09h 0Ah 0Bh 0Ch 0Dh 0Eh 0Fh 10h 11h 12h 13h 14h 15h 16h 17h 18h 19h 1Ah 1Bh 1Ch 1Dh 1Eh 1Fh 20h File Address Indirect addr.(*) 80h OPTION_REG 81h 82h PCL 83h STATUS 84h FSR 85h TRISA 86h TRISB 87h 88h 89h 8Ah PCLATH 8Bh INTCON 8Ch PIE1 8Dh PIE2 8Eh PCON 8Fh 90h 91h SSPCON2 92h PR2 93h SSPADD 94h SSPSTAT WPUB 95h IOCB 96h 97h P1DEL 98h 99h 9Ah 9Bh REFCON LVDCON 9Ch ANSEL 9Dh ADRESL 9Eh ADCON1 9Fh 96 Bytes accesses 70h-7Fh 7Fh Bank 0 * Indirect addr.(*) TMR0 PCL STATUS FSR PORTB PCLATH INTCON PMDATL PMADRL PMDATH PMADRH A0h General Purpose Register 80 Bytes General Purpose Register File Address 100h 101h 102h 103h 104h 105h 106h 107h 108h 109h 10Ah 10Bh 10Ch 10Dh 10Eh 10Fh 110h 111h 112h 113h 114h 115h 116h 117h 118h 119h 11Ah 11Bh 11Ch 11Dh 11Eh 11Fh 120h File Address Indirect addr.(*) OPTION_REG PCL STATUS FSR TRISB PCLATH INTCON PMCON1 180h 181h 182h 183h 184h 185h 186h 187h 188h 189h 18Ah 18Bh 18Ch 18Dh 18Eh 18Fh 190h 191h 192h 193h 194h 195h 196h 197h 198h 199h 19Ah 19Bh 19Ch 19Dh 19Eh 19Fh 1A0h General Purpose Register 80 Bytes EFh F0h accesses 70h - 7Fh accesses 70h - 7Fh 17Fh FFh Bank 1 6Fh 70h Bank 2 1EFh 1F0h 1FFh Bank 3 Unimplemented data memory locations, read as '0'. Not a physical register. DS41120A-page 12 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 2.2.2 SPECIAL FUNCTION REGISTERS The special function registers can be classified into two sets; core (CPU) and peripheral. Those registers associated with the core functions are described in detail in this section. Those related to the operation of the peripheral features are described in detail in that peripheral feature section. The Special Function Registers are registers used by the CPU and Peripheral Modules for controlling the desired operation of the device. These registers are implemented as static RAM. A list of these registers is given in Table 2-1. TABLE 2-1: PIC16C717/770/771 SPECIAL FUNCTION REGISTER SUMMARY Address Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Value on: POR, BOR Value on all other resets (2) Bank 0 00h(3) INDF Addressing this location uses contents of FSR to address data memory (not a physical register) 0000 0000 0000 0000 01h TMR0 Timer0 module's register xxxx xxxx uuuu uuuu 02h PCL Program Counter's (PC) Least Significant Byte 03h(3) STATUS 04h(3) FSR 05h PORTA 06h PORTB 07h -- Unimplemented -- -- 08h -- Unimplemented -- -- 09h -- Unimplemented -- -- (3) 0Ah (1,3) 0Bh(3) IRP RP1 RP0 0000 0000 0000 0000 TO PD Z DC C Indirect data memory address pointer 0001 1xxx 000q quuu xxxx xxxx uuuu uuuu RA7 RA6 RA5 RA4 RA3 RA2 RA1 RA0 xxxx 0000 uuuu 0000 RB7 RB6 RB5 RB4 RB3 RB2 RB1 RB0 xxxx xx00 uuuu uu00 PCLATH -- -- -- INTCON GIE PEIE T0IE Write Buffer for the upper 5 bits of the Program Counter INTE RBIE T0IF INTF RBIF ---0 0000 ---0 0000 0000 000x 0000 000u 0Ch PIR1 -- ADIF -- -- SSPIF CCP1IF TMR2IF TMR1IF -0-- 0000 -0-- 0000 0Dh PIR2 LVDIF -- -- -- BCLIF -- -- -- 0--- 0--- 0--- 0--- 0Eh TMR1L Holding register for the Least Significant Byte of the 16-bit TMR1 register xxxx xxxx uuuu uuuu 0Fh TMR1H Holding register for the Most Significant Byte of the 16-bit TMR1 register xxxx xxxx uuuu uuuu 10h T1CON 11h TMR2 12h T2CON 13h SSPBUF 14h SSPCON 15h CCPR1L Capture/Compare/PWM Register1 (LSB) 16h CCPR1H Capture/Compare/PWM Register1 (MSB) 17h CCP1CON PWM1M1 -- -- T1CKPS1 T1CKPS0 T1OSCEN T1SYNC TMR1CS TMR1ON Timer2 module's register -- TOUTPS3 0000 0000 0000 0000 TOUTPS2 TOUTPS1 TOUTPS0 TMR2ON T2CKPS1 T2CKPS0 -000 0000 -000 0000 Synchronous Serial Port Receive Buffer/Transmit Register WCOL SSPOV PWM1M0 --00 0000 --uu uuuu SSPEN DC1B1 CKP SSPM3 xxxx xxxx uuuu uuuu SSPM2 SSPM1 SSPM0 0000 0000 0000 0000 xxxx xxxx uuuu uuuu xxxx xxxx uuuu uuuu DC1B0 CCP1M3 CCP1M2 CCP1M1 CCP1M0 0000 0000 0000 0000 18h -- Unimplemented -- -- 19h -- Unimplemented -- -- 1Ah -- Unimplemented -- -- 1Bh -- Unimplemented -- -- 1Ch -- Unimplemented -- -- 1Dh -- Unimplemented -- -- 1Eh ADRESH 1Fh ADCON0 A/D High Byte Result Register ADCS1 ADCS0 CHS2 xxxx xxxx uuuu uuuu CHS1 CHS0 GO/DONE CHS3 ADON 0000 0000 0000 0000 Legend: x = unknown, u = unchanged, q = value depends on condition, - = unimplemented read as '0'. Shaded locations are unimplemented, read as `0'. Note 1: The upper byte of the program counter is not directly accessible. PCLATH is a holding register for the PC<12:8> whose contents are transferred to the upper byte of the program counter. 2: Other (non power-up) resets include external reset through MCLR and Watchdog Timer Reset. 3: These registers can be addressed from any bank. 1999 Microchip Technology Inc. Advanced Information DS41120A-page 13 PIC16C717/770/771 TABLE 2-1: PIC16C717/770/771 SPECIAL FUNCTION REGISTER SUMMARY (CONTINUED) Address Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Value on: POR, BOR Value on all other resets (2) Bank 1 80h(3) INDF 81h OPTION_REG 82h(3) PCL (3) Addressing this location uses contents of FSR to address data memory (not a physical register) RBPU INTEDG T0CS T0SE PSA PS2 PS1 PS0 Program Counter's (PC) Least Significant Byte 83h STATUS 84h(3) FSR IRP RP1 RP0 TO 0000 0000 0000 0000 1111 1111 1111 1111 0000 0000 0000 0000 PD Z DC C 0001 1xxx 000q quuu Indirect data memory address pointer xxxx xxxx uuuu uuuu 85h TRISA PORTA Data Direction Register 1111 1111 1111 1111 86h TRISB PORTB Data Direction Register 1111 1111 1111 1111 87h -- Unimplemented -- -- 88h -- Unimplemented -- -- -- Unimplemented -- -- 89h 8Ah(1,3) PCLATH -- 8Bh(3) INTCON 8Ch PIE1 8Dh PIE2 8Eh PCON -- -- Write Buffer for the upper 5 bits of the Program Counter GIE PEIE T0IE INTE RBIE T0IF INTF RBIF 0000 000x 0000 000u -- ADIE -- -- SSPIE CCP1IE TMR2IE TMR1IE -0-- 0000 -0-- 0000 LVDIE -- -- -- BCLIE -- -- -- 0--- 0--- 0--- 0--- -- -- -- -- OSCF -- POR BOR ---- 1-qq ---- 1-uu ---0 0000 ---0 0000 8Fh -- Unimplemented -- -- 90h -- Unimplemented -- -- 91h SSPCON2 92h PR2 GCEN ACKSTAT ACKDT ACKEN RCEN PEN RSEN SEN Timer2 Period Register 0000 0000 0000 0000 1111 1111 1111 1111 Synchronous Serial Port (I 2C mode) Address Register 93h SSPADD 94h SSPSTAT 95h WPUB PORTB Weak Pull-up Control 1111 1111 1111 1111 96h IOCB PORTB Interrupt on Change Control 1111 0000 1111 0000 97h P1DEL PWM 1 Delay value 0000 0000 0000 0000 SMP CKE D/A P 0000 0000 0000 0000 S R/W UA BF 0000 0000 0000 0000 98h -- Unimplemented -- -- 99h -- Unimplemented -- -- 9Ah -- Unimplemented -- -- 9Bh REFCON VRHEN VRLEN VRHOEN VRLOEN -- -- -- -- 0000 ---- 0000 ---- 9Ch LVDCON -- -- BGST LVDEN LVV3 LVV2 LVV1 LVV0 --00 0101 --00 0101 9Dh ANSEL 9Eh ADRESL 9Fh ADCON1 Analog Channel Select A/D Low Byte Result Register ADFM VCFG2 VCFG1 1111 1111 1111 1111 xxxx xxxx uuuu uuuu VCFG0 0000 0000 0000 0000 Legend: x = unknown, u = unchanged, q = value depends on condition, - = unimplemented read as '0'. Shaded locations are unimplemented, read as `0'. Note 1: The upper byte of the program counter is not directly accessible. PCLATH is a holding register for the PC<12:8> whose contents are transferred to the upper byte of the program counter. 2: Other (non power-up) resets include external reset through MCLR and Watchdog Timer Reset. 3: These registers can be addressed from any bank. DS41120A-page 14 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 TABLE 2-1: PIC16C717/770/771 SPECIAL FUNCTION REGISTER SUMMARY (CONTINUED) Address Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Value on: POR, BOR Value on all other resets (2) Bank 2 100h(3) INDF Addressing this location uses contents of FSR to address data memory (not a physical register) 0000 0000 0000 0000 101h TMR0 Timer0 module's register xxxx xxxx uuuu uuuu (3) PCL Program Counter's (PC) Least Significant Byte 0000 0000 0000 0000 (3) STATUS 0001 1xxx 000q quuu (3) FSR xxxx xxxx uuuu uuuu 102h 103h 104h IRP RP1 105h -- PORTB 107h -- 108h -- -- Unimplemented (1,3) Z DC C Unimplemented -- -- xxxx xx00 uuuu uu00 Unimplemented -- -- Unimplemented -- -- -- -- ---0 0000 ---0 0000 0000 000x 0000 000u Program memory read data low xxxx xxxx uuuu uuuu Program memory read address low xxxx xxxx uuuu uuuu --xx xxxx --uu uuuu ---- xxxx ---- uuuu -- -- 0000 0000 0000 0000 1111 1111 1111 1111 0000 0000 0000 0000 0001 1xxx 000q quuu xxxx xxxx uuuu uuuu -- -- -- 10Bh(3) INTCON GIE PEIE T0IE 10Ch PMDATL 10Dh PMADRL 10Eh PMDATH -- -- 10Fh PMADRH -- -- 110h11Fh PD PORTB Data Latch when written: PORTB pins when read PCLATH 10Ah TO Indirect data memory address pointer 106h 109h RP0 -- Write Buffer for the upper 5 bits of the Program Counter INTE RBIE T0IF INTF RBIF Program memory read data high -- -- Program memory read address high Unimplemented Bank 3 180h(3) INDF 181h OPTION_REG 182h(3) PCL Addressing this location uses contents of FSR to address data memory (not a physical register) STATUS (3) FSR 184h 185h T0CS T0SE PSA PS2 PS1 PS0 IRP RP1 RP0 TO PD Z DC C Indirect data memory address pointer -- 186h INTEDG Program Counter's (PC) Least Significant Byte (3) 183h RBPU TRISB Unimplemented PORTB Data Direction Register -- -- 1111 1111 1111 1111 187h -- Unimplemented -- -- 188h -- Unimplemented -- -- -- Unimplemented 189h (1,3) -- -- -- 18Bh(3) INTCON GIE PEIE T0IE INTE RBIE T0IF INTF 18Ch PMCON1 Reserved -- -- -- -- -- -- 18Ah 18Dh18Fh -- -- -- ---0 0000 ---0 0000 RBIF 0000 000x 0000 000u RD 1--- ---0 1--- ---0 -- -- Write Buffer for the upper 5 bits of the Program Counter PCLATH Unimplemented Legend: x = unknown, u = unchanged, q = value depends on condition, - = unimplemented read as '0'. Shaded locations are unimplemented, read as `0'. Note 1: The upper byte of the program counter is not directly accessible. PCLATH is a holding register for the PC<12:8> whose contents are transferred to the upper byte of the program counter. 2: Other (non power-up) resets include external reset through MCLR and Watchdog Timer Reset. 3: These registers can be addressed from any bank. 1999 Microchip Technology Inc. Advanced Information DS41120A-page 15 PIC16C717/770/771 2.2.2.1 STATUS REGISTER For example, CLRF STATUS will clear the upper-three bits and set the Z bit. This leaves the STATUS register as 000u u1uu (where u = unchanged). The STATUS register, shown in Register 2-1, contains the arithmetic status of the ALU, the RESET status and the bank select bits for data memory. It is recommended, therefore, that only BCF, BSF, SWAPF and MOVWF instructions are used to alter the STATUS register, because these instructions do not affect the Z, C or DC bits from the STATUS register. For other instructions not affecting any status bits, see the "Instruction Set Summary." The STATUS register can be the destination for any instruction, as with any other register. If the STATUS register is the destination for an instruction that affects the Z, DC or C bits, then the write to these three bits is disabled. These bits are set or cleared according to the device logic. Furthermore, the TO and PD bits are not writable. Therefore, the result of an instruction with the STATUS register as destination may be different than intended. REGISTER 2-1: Note 2: The C and DC bits operate as a borrow and digit borrow bit, respectively, in subtraction. See the SUBLW and SUBWF instructions for examples. STATUS REGISTER (STATUS: 03h, 83h, 103h, 183h) R/W-0 R/W-0 R/W-0 R-1 R-1 R/W-x R/W-x R/W-x IRP RP1 RP0 TO PD Z DC C bit7 bit 7: bit0 R = Readable bit W = Writable bit U = Unimplemented bit, read as `0' - n = Value at POR reset IRP: Register Bank Select bit (used for indirect addressing) 1 = Bank 2, 3 (100h - 1FFh) 0 = Bank 0, 1 (00h - FFh) bit 6-5: RP<1:0>: Register Bank Select bits (used for direct addressing) 11 = Bank 3 (180h - 1FFh) 10 = Bank 2 (100h - 17Fh) 01 = Bank 1 (80h - FFh) 00 = Bank 0 (00h - 7Fh) Each bank is 128 bytes bit 4: TO: Time-out bit 1 = After power-up, CLRWDT instruction, or SLEEP instruction 0 = A WDT time-out occurred bit 3: PD: Power-down bit 1 = After power-up or by the CLRWDT instruction 0 = By execution of the SLEEP instruction 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 (ADDWF, ADDLW,SUBLW,SUBWF instructions) (for borrow the polarity is reversed) 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 (ADDWF, ADDLW,SUBLW,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: For borrow, the polarity is reversed. A subtraction is executed by adding the two'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. DS41120A-page 16 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 2.2.2.2 OPTION_REG REGISTER Note: The OPTION_REG register is a readable and writable register, which contains various control bits to configure the TMR0 prescaler/WDT postscaler (single assignable register known also as the prescaler), the External INT Interrupt, TMR0 and the weak pull-ups on PORTB. REGISTER 2-2: To achieve a 1:1 prescaler assignment for the TMR0 register, assign the prescaler to the Watchdog Timer. OPTION REGISTER (OPTION_REG: 81h, 181h) 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 INTEDG T0CS T0SE PSA PS2 PS1 PS0 bit7 bit0 bit 7: RBPU: PORTB Pull-up Enable bit(1) 1 = PORTB weak pull-ups are disabled 0 = PORTB weak pull-ups are enabled by the WPUB register bit 6: INTEDG: Interrupt Edge Select bit 1 = Interrupt on rising edge of RB0/INT pin 0 = Interrupt on falling edge of RB0/INT pin bit 5: T0CS: TMR0 Clock Source Select bit 1 = Transition on RA4/T0CKI pin 0 = Internal instruction cycle clock (CLKOUT) bit 4: T0SE: TMR0 Source Edge Select bit 1 = Increment on high-to-low transition on RA4/T0CKI pin 0 = Increment on low-to-high transition on RA4/T0CKI pin bit 3: PSA: Prescaler Assignment bit 1 = Prescaler is assigned to the WDT 0 = Prescaler is assigned to the Timer0 module R = Readable bit W = Writable bit U = Unimplemented bit, read as `0' - n = Value at POR reset bit 2-0: PS<2:0>: Prescaler Rate Select bits Bit Value 000 001 010 011 100 101 110 111 TMR0 Rate 1:2 1:4 1:8 1 : 16 1 : 32 1 : 64 1 : 128 1 : 256 WDT Rate 1:1 1:2 1:4 1:8 1 : 16 1 : 32 1 : 64 1 : 128 Note 1: Individual weak pull-up on RB pins can be enabled/disabled from the weak pull-up PORTB Register (WPUB). 1999 Microchip Technology Inc. Advanced Information DS41120A-page 17 PIC16C717/770/771 2.2.2.3 INTCON REGISTER Note: The INTCON Register is a readable and writable register, which contains various enable and flag bits for the TMR0 register overflow, RB Port change and External RB0/INT pin interrupts. REGISTER 2-3: Interrupt flag bits get set when an interrupt condition occurs, regardless of the state of its corresponding enable bit or the global enable bit, GIE (INTCON<7>). User software should ensure the appropriate interrupt flag bits are clear prior to enabling an interrupt. INTERRUPT CONTROL REGISTER (INTCON: 0Bh, 8Bh, 10Bh, 18Bh) 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 PEIE T0IE INTE RBIE T0IF INTF RBIF bit7 bit0 R = Readable bit W = Writable bit U = Unimplemented bit, read as `0' - n = Value at POR reset bit 7: GIE: Global Interrupt Enable bit 1 = Enables all un-masked interrupts 0 = Disables all interrupts bit 6: PEIE: Peripheral Interrupt Enable bit 1 = Enables all un-masked peripheral interrupts 0 = Disables all peripheral interrupts bit 5: T0IE: TMR0 Overflow Interrupt Enable bit 1 = Enables the TMR0 interrupt 0 = Disables the TMR0 interrupt bit 4: INTE: RB0/INT External Interrupt Enable bit 1 = Enables the RB0/INT external interrupt 0 = Disables the RB0/INT external interrupt bit 3: RBIE: RB Port Change Interrupt Enable bit(1) 1 = Enables the RB port change interrupt 0 = Disables the RB port change interrupt bit 2: T0IF: TMR0 Overflow Interrupt Flag bit 1 = TMR0 register has overflowed (must be cleared in software) 0 = TMR0 register did not overflow bit 1: INTF: RB0/INT External Interrupt Flag bit 1 = The RB0/INT external interrupt occurred (must be cleared in software) 0 = The RB0/INT external interrupt did not occur bit 0: RBIF: RB Port Change Interrupt Flag bit(1) 1 = At least one of the RB<7:0> pins changed state (must be cleared in software) 0 = None of the RB<7:0> pins have changed state Note 1: Individual RB pin interrupt on change can be enabled/disabled from the Interrupt on Change PORTB register (IOCB). DS41120A-page 18 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 2.2.2.4 PIE1 REGISTER Note: This register contains the individual enable bits for the peripheral interrupts. REGISTER 2-4: Bit PEIE (INTCON<6>) must be set to enable any peripheral interrupt. PERIPHERAL INTERRUPT ENABLE REGISTER 1 (PIE1: 8Ch) U-0 R/W-0 U-0 U-0 R/W-0 R/W-0 R/W-0 R/W-0 -- ADIE -- -- SSPIE CCP1IE TMR2IE TMR1IE bit7 bit0 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 R = Readable bit W = Writable bit U = Unimplemented bit, read as `0' - n = Value at POR reset bit 5-4: Unimplemented: Read as '0' bit 3: SSPIE: Synchronous Serial Port Interrupt Enable bit 1 = Enables the SSP interrupt 0 = Disables the SSP interrupt bit 2: CCP1IE: CCP1 Interrupt Enable bit 1 = Enables the CCP1 interrupt 0 = Disables the CCP1 interrupt 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 1999 Microchip Technology Inc. Advanced Information DS41120A-page 19 PIC16C717/770/771 2.2.2.5 PIR1 REGISTER Note: This register contains the individual flag bits for the peripheral interrupts. REGISTER 2-5: U-0 -- R/W-0 ADIF Interrupt flag bits get set when an interrupt condition occurs, regardless of the state of its corresponding enable bit or the global enable bit, GIE (INTCON<7>). User software should ensure the appropriate interrupt flag bits are clear prior to enabling an interrupt. PERIPHERAL INTERRUPT REGISTER 1 (PIR1: 0Ch) U-0 U-0 -- -- R/W-0 SSPIF R/W-0 CCP1IF R/W-0 TMR2IF R/W-0 TMR1IF bit7 bit0 bit 7: Unimplemented: Read as `0'. bit 6: ADIF: A/D Converter Interrupt Flag bit 1 = An A/D conversion completed 0 = The A/D conversion is not complete R = Readable bit W = Writable bit U = Unimplemented bit, read as `0' - n = Value at POR reset bit 5-4: Unimplemented: Read as `0'. bit 3: SSPIF: Synchronous Serial Port (SSP) Interrupt Flag 1 = The SSP interrupt condition has occurred, and must be cleared in software before returning from the interrupt service routine. The conditions that will set this bit are: SPI A transmission/reception has taken place. I2C Slave / Master A transmission/reception has taken place. I2C Master The initiated start condition was completed by the SSP module. The initiated stop condition was completed by the SSP module. The initiated restart condition was completed by the SSP module. The initiated acknowledge condition was completed by the SSP module. A start condition occurred while the SSP module was idle (Multimaster system). A stop condition occurred while the SSP module was idle (Multimaster system). 0 = No SSP interrupt condition has occurred. bit 2: CCP1IF: CCP1 Interrupt Flag bit Capture Mode 1 = A TMR1 register capture occurred (must be cleared in software) 0 = No TMR1 register capture occurred Compare Mode 1 = A TMR1 register compare match occurred (must be cleared in software) 0 = No TMR1 register compare match occurred PWM Mode Unused in this mode bit 1: TMR2IF: TMR2 to PR2 Match Interrupt Flag bit 1 = TMR2 to PR2 match occurred (must be cleared in software) 0 = No TMR2 to PR2 match occurred bit 0: TMR1IF: TMR1 Overflow Interrupt Flag bit 1 = TMR1 register overflowed (must be cleared in software) 0 = TMR1 register did not overflow DS41120A-page 20 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 2.2.2.6 PIE2 REGISTER This register contains the individual enable bits for the SSP bus collision and low voltage detect interrupts. REGISTER 2-6: PERIPHERAL INTERRUPT REGISTER 2 (PIE2: 8Dh) R/W-0 U-0 U-0 U-0 R/W-0 U-0 U-0 U-0 LVDIE -- -- -- BCLIE -- -- -- bit7 bit 7: bit0 R = Readable bit W = Writable bit U = Unimplemented bit, read as `0' - n = Value at POR reset LVDIE: Low-voltage Detect Interrupt Enable bit 1 = LVD Interrupt is enabled 0 = LVD Interrupt is disabled bit 6-4: Unimplemented: Read as '0' bit 3: BCLIE: Bus Collision Interrupt Enable bit 1 = Bus Collision interrupt is enabled 0 = Bus Collision interrupt is disabled bit 2-0: Unimplemented: Read as '0' 1999 Microchip Technology Inc. Advanced Information DS41120A-page 21 PIC16C717/770/771 2.2.2.7 PIR2 REGISTER . Note: This register contains the SSP Bus Collision and lowvoltage detect interrupt flag bits. REGISTER 2-7: Interrupt flag bits get set when an interrupt condition occurs, regardless of the state of its corresponding enable bit or the global enable bit, GIE (INTCON<7>). User software should ensure the appropriate interrupt flag bits are clear prior to enabling an interrupt. PERIPHERAL INTERRUPT REGISTER 2 (PIR2: 0Dh) R/W-0 U-0 U-0 U-0 R/W-0 U-0 U-0 U-0 LVDIF -- -- -- BCLIF -- -- -- bit7 bit 7: bit0 R = Readable bit W = Writable bit U = Unimplemented bit, read as `0' - n = Value at POR reset LVDIF: Low-voltage Detect Interrupt Flag bit 1 = The supply voltage has fallen below the specified LVD voltage (must be cleared in software) 0 = The supply voltage is greater than the specified LVD voltage bit 6-4: Unimplemented: Read as '0' bit 3: BCLIF: Bus Collision Interrupt Flag bit 1 = A bus collision has occurred while the SSP module configured in I2C Master was transmitting (must be cleared in software) 0 = No bus collision occurred bit 2-0: Unimplemented: Read as '0' DS41120A-page 22 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 2.2.2.8 PCON REGISTER Note: The Power Control (PCON) register contains a flag bit to allow differentiation between a Power-on Reset (POR) to an external MCLR Reset or WDT Reset. Those devices with brown-out detection circuitry contain an additional bit to differentiate a Brown-out Reset condition from a Power-on Reset condition. The PCON register also contains the frequency select bit of the INTRC or ER oscillator. REGISTER 2-8: U-0 -- bit7 U-0 -- BOR is unknown on Power-on Reset. It must then be set by the user and checked on subsequent resets to see if BOR is clear, indicating a brown-out has occurred. The BOR status bit is a don't care and is not necessarily predictable if the brown-out circuit is disabled (by clearing the BODEN bit in the Configuration word). POWER CONTROL REGISTER (PCON: 8Eh) U-0 -- U-0 -- R/W-1 OSCF U-0 -- R/W-q POR R/W-q BOR bit0 R = Readable bit W = Writable bit U = Unimplemented bit, read as `0' - n = Value at POR reset bit 7-4,2: Unimplemented: Read as '0' bit 3: OSCF: Oscillator speed INTRC Mode 1 = 4 MHz nominal 0 = 37 KHz nominal ER Mode 1 = Oscillator frequency depends on the external resistor value on the OSC1 pin. 0 = 37 KHz nominal All other modes x = Ignored bit 1: POR: Power-on Reset Status bit 1 = No Power-on Reset occurred 0 = A Power-on Reset occurred (must be set in software after a Power-on Reset occurs) bit 0: BOR: Brown-out Reset Status bit 1 = No Brown-out Reset occurred 0 = A Brown-out Reset occurred (must be set in software after a Brown-out Reset occurs) 1999 Microchip Technology Inc. Advanced Information DS41120A-page 23 PIC16C717/770/771 2.3 PCL and PCLATH 2.4 The program counter (PC) specifies the address of the instruction to fetch for execution. The PC is 13 bits wide. The low byte is called the PCL register. This register is readable and writable. The high byte is called the PCH register. This register contains the PC<12:8> bits and is not directly readable or writable. All updates to the PCH register occur through the PCLATH register. 2.3.1 PROGRAM MEMORY PAGING PIC16C717/770/771 devices are capable of addressing a continuous 8K word block of program memory. The CALL and GOTO instructions provide only 11 bits of address to allow branching within any 2K program memory page. When doing a CALL or GOTO instruction, the upper 2 bits of the address are provided by PCLATH<4:3>. When doing a CALL or GOTO instruction, the user must ensure that the page select bits are programmed so that the desired program memory page is addressed. A return instruction pops a PC address off the stack onto the PC register. Therefore, manipulation of the PCLATH<4:3> bits are not required for the return instructions (which POPs the address from the stack). DS41120A-page 24 Stack The stack allows a combination of up to 8 program calls and interrupts to occur. The stack contains the return address from this branch in program execution. Mid-range devices have an 8-level deep x 13-bit wide hardware stack. The stack space is not part of either program or data space and the stack pointer is not readable or writable. The PC is PUSHed onto the stack when a CALL instruction is executed or an interrupt causes a branch. The stack is POPed in the event of a RETURN, RETLW or a RETFIE instruction execution. PCLATH is not modified when the stack is PUSHed or POPed. After the stack has been PUSHed eight times, the ninth push overwrites the value that was stored from the first push. The tenth push overwrites the second push (and so on). Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 The INDF register is not a physical register. Addressing INDF actually addresses the register whose address is contained in the FSR register (FSR is a pointer). This is indirect addressing. EXAMPLE 2-1: Reading INDF itself indirectly (FSR = 0) will produce 00h. Writing to the INDF register indirectly results in a no-operation (although STATUS bits may be affected). movlw movwf clrf incf btfss goto NEXT A simple program to clear RAM locations 20h-2Fh using indirect addressing is shown in Example 2-1. HOW TO CLEAR RAM USING INDIRECT ADDRESSING 0x20 FSR INDF FSR FSR,4 NEXT ;initialize pointer ; to RAM ;clear INDF register ;inc pointer ;all done? ;NO, clear next CONTINUE : ;YES, continue An effective 9-bit address is obtained by concatenating the 8-bit FSR register and the IRP bit (STATUS<7>), as shown in Figure 2-4. FIGURE 2-4: DIRECT/INDIRECT ADDRESSING Direct Addressing Indirect Addressing from opcode RP1:RP0 6 bank select location select 0 IRP 7 bank select 00 01 10 FSR register 0 location select 11 00h 80h 100h 180h 7Fh FFh 17Fh 1FFh Data Memory(1) Bank 0 Note 1: Bank 1 Bank 2 Bank 3 For register file map detail see Figure 2-3. 1999 Microchip Technology Inc. Advanced Information DS41120A-page 25 PIC16C717/770/771 NOTES: DS41120A-page 26 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 3.0 I/O PORTS Some pins for these I/O ports are multiplexed with an alternate function for 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. Additional information on I/O ports may be found in the PICmicroTM Mid-Range Reference Manual, (DS33023). 3.1 present on a pin, the pin must be configured as an analog input to prevent unnecessary current draw from the power supply. The Analog Select Register (ANSEL) allows the user to individually select the digital/analog mode on these pins. When the analog mode is active, the port pin will always read 0. Note 1: On a Power-on Reset, the ANSEL register configures these mixed-signal pins as analog mode. I/O Port Analog/Digital Mode 2: If a pin is configured as analog mode, the pin will always read '0', even if the digital output is active. The PIC16C717/770/771 have two I/O ports: PORTA and PORTB. Some of these port pins are mixed-signal (can be digital or analog). When an analog signal is REGISTER 3-1: R/W-1 R/W-1 ANALOG SELECT REGISTER (ANSEL: 9Dh) R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 R/W-1 ANS5 ANS4 ANS3 ANS2 ANS1 ANS0 bit7 bit0 R = Readable bit W = Writable bit U = Unimplemented bit, read as `0' -n = Value at POR reset bit 7-6: Reserved: Do not use bit 5-0: ANS<5:0>: Analog Select between analog or digital function on pins AN<5:0>, respectively. 0 = Digital I/O. Pin is assigned to port or special function. 1 = Analog Input. Pin is assigned as analog input. Note: 3.2 Setting a pin to an analog input disables digital inputs and any pull-up that may be present. The corresponding TRIS bit should be set to input mode when using pins as analog inputs. PORTA and the TRISA Register PORTA is a 8-bit wide bi-directional port. The corresponding data direction register is TRISA. Setting a TRISA bit (=1) will make the corresponding PORTA pin an input, i.e., put the corresponding output driver in a hi-impedance mode. Clearing a TRISA bit (=0) will make the corresponding PORTA pin an output, i.e., put the contents of the output latch on the selected pin. Reading the PORTA register reads the status of the pins, whereas writing to it will write to the port latch. All write operations are read-modify-write operations. Therefore, a write to a port implies that the port pins are read, this value is modified, and then written to the port data latch. Pins RA<3:0> are multiplexed with analog functions, such as analog inputs to the A/D converter, analog VREF inputs, and the on-board bandgap reference outputs. When the analog peripherals are using any of 1999 Microchip Technology Inc. these pins as analog input/output, the ANSEL register must have the proper value to individually select the analog mode of the corresponding pins. Note: Upon reset, the ANSEL register configures the RA<3:0> pins as analog inputs. All RA<3:0> pins will read as '0'. Pin RA4 is multiplexed with the Timer0 module clock input to become the RA4/T0CKI pin. The RA4/T0CKI pin is a Schmitt Trigger input and an open drain output. Pin RA5 is multiplexed with the device reset (MCLR) and programming input (VPP) functions. The RA5/ MCLR/VPP input only pin has a Schmitt Trigger input buffer. All other RA port pins have Schmitt Trigger input buffers and full CMOS output buffers. Pins RA6 and RA7 are multiplexed with the oscillator input and output functions. The TRISA register controls the direction of the RA 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. Advanced Information DS41120A-page 27 PIC16C717/770/771 EXAMPLE 3-1: INITIALIZING PORTA BCF CLRF STATUS, RP0 PORTA BSF MOVLW STATUS, RP0 0Fh MOVWF TRISA MOVLW MOVWF BCF 03 ANSEL STATUS, RP0 FIGURE 3-1: ; ; ; ; ; ; ; ; ; ; ; Select Bank 0 Initialize PORTA by clearing output data latches Select Bank 1 Value used to initialize data direction Set RA<3:0> as inputs RA<7:4> as outputs. RA<7:6>availability depends on oscillator selection. Set RA<1:0> as analog inputs, RA<7:2> are digital I/O ; Return to Bank 0 BLOCK DIAGRAM OF RA0/AN0, RA1/AN1/LVDIN Data Bus WR PORT Data Latch D Q VDD VDD CK Q P TRIS Mode D WR TRIS CK Q N Q VSS VSS RD TRIS Analog Select D Schmitt Trigger Q WR ANSEL CK Q Q D EN RD PORT To A/D Converter input or LVD Module input DS41120A-page 28 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 FIGURE 3-2: BLOCK DIAGRAM OF RA2/AN2/VREF-/VRL AND RA3/AN3/VREF+/VRH Data Bus WR PORT Data Latch D Q VDD VDD CK Q P TRIS Mode D WR TRIS CK Q N Q VSS VSS RD TRIS Analog Select D WR ANSEL CK Q Schmitt Trigger Q Q D EN RD PORT To A/D Converter input and Vref+, Vref- inputs VRH, VRL outputs (From Vref-LVD-BOR Module) VRH, VRL output enable Sense input for VRH, VRL amplifier 1999 Microchip Technology Inc. Advanced Information DS41120A-page 29 PIC16C717/770/771 FIGURE 3-3: BLOCK DIAGRAM OF RA4/T0CKI Data Bus WR Port Data Latch D CK Q Q TRIS Latch D WR TRIS CK Q N Q VSS VSS RD TRIS Schmitt Trigger Input Buffer Q D EN RD PORT TMR0 clock input DS41120A-page 30 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 FIGURE 3-4: BLOCK DIAGRAM OF RA5/MCLR/VPP To MCLR Circuit MCLR Filter Program Mode HV Detect Data Bus RD TRIS VSS VSS Schmitt Trigger Q D EN RD PORT 1999 Microchip Technology Inc. Advanced Information DS41120A-page 31 PIC16C717/770/771 FIGURE 3-5: BLOCK DIAGRAM OF RA6/OSC2/CLKOUT PIN INTRC or ER with CLKOUT From OSC1 Oscillator Circuit CLKOUT (FOSC/4) 1 0 VDD Data Bus D WR PORTA VDD Q Q CK P INTRC or ER Data Latch D VSS Q N WR TRISA CK Q TRIS Latch INTRC or ER without CLKOUT INTRC or ER with CLKOUT VSS Schmitt Trigger Input Buffer RD TRISA Q D EN RD PORTA DS41120A-page 32 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 FIGURE 3-6: BLOCK DIAGRAM OF RA7/OSC1/CLKIN PIN To OSC2 Oscillator Circuit VDD To Chip Clock Drivers Data Bus WR PORTA D CK VDD Q P Schmitt Trigger Input Buffer EC Mode Data Latch D WR TRISA Q Q N CK Q TRIS Latch INTRC VSS INTRC RD TRISA Schmitt Trigger Input Buffer Q D EN RD PORTA 1999 Microchip Technology Inc. Advanced Information DS41120A-page 33 PIC16C717/770/771 TABLE 3-1: PORTA FUNCTIONS Name RA0/AN0 RA1/AN1/LVDIN RA2/AN2/VREF-/VRL Input Type Output Type RA0 ST CMOS AN0 AN RA1 ST Function RA5/MCLR/VPP RA6/OSC2/CLKOUT RA7/OSC1/CLKIN DS41120A-page 34 CMOS Bi-directional I/O AN1 AN A/D input AN LVD input reference RA2 ST CMOS Bi-directional I/O AN2 AN A/D input VREF- AN Negative analog reference input AN RA3 ST AN3 AN VREF+ AN VRH RA4/T0CKI Bi-directional I/O A/D input LVDIN VRL RA3/AN3/VREF+/VRH Description RA4 ST CMOS Internal voltage reference low output Bi-directional I/O A/D input Positive analog reference input AN Internal voltage reference high output OD Bi-directional I/O T0CKI ST TMR0 clock input RA5 ST Input port MCLR ST VPP Power RA6 ST Master clear Programming voltage CMOS Bi-directional I/O OSC2 XTAL Crystal/resonator CLKOUT CMOS FOSC/4 output CMOS Bi-directional I/O RA7 ST OSC1 XTAL CLKIN ST Crystal/resonator External clock input/ER resistor connection Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 TABLE 3-2: SUMMARY OF REGISTERS ASSOCIATED WITH PORTA Address Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Value on: POR, BOR 05h PORTA RA7 RA6 RA5 RA4 RA3 RA2 RA1 RA0 xxxx 0000 uuuu 0000 1111 1111 1111 1111 1111 1111 1111 1111 85h TRISA 9Dh ANSEL PORTA Data Direction Register ANS5 ANS4 ANS3 ANS2 ANS1 ANS0 Value on all other resets Legend: x = unknown, u = unchanged, - = unimplemented locations read as '0'. Shaded cells are not used by PORTA. PORTB and the TRISB Register 3.3 enables the weak pull-up resistors. 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. PORTB is an 8-bit wide bi-directional port. The corresponding data direction register is TRISB. Setting a TRISB bit (=1) will make the corresponding PORTB pin an input, i.e., put the corresponding output driver in a hi-impedance mode. Clearing a TRISB bit (=0) will make the corresponding PORTB pin an output, i.e., put the contents of the output latch on the selected pin. EXAMPLE 3-2: Each of the PORTB pins, if configured as input, also has an interrupt on change feature, which can be individually selected from the IOCB register. The RBIE bit in the INTCON register functions as a global enable bit to turn on/off the interrupt on change feature. The selected inputs are compared to the old value latched on the last read of PORTB. The "mismatch" outputs are OR'ed together to generate the RB Port Change Interrupt with flag bit RBIF (INTCON<0>). INITIALIZING PORTB BCF CLRF STATUS, RP0 PORTB MOVLW 03 ; ; ; ; ; ; ; ; ; ; ; ; BSF MOVLW STATUS, RP0 0xCF MOVWF TRISB MOVWF BCF ANSEL STATUS, RP0 ; ; Return to Bank 0 Initialize PORTB by clearing output data latches Select Bank 1 Value used to initialize data direction Set RB<3:0> as inputs RB<5:4> as outputs RB<7:6> as inputs Set RB<1:0> as analog inputs This interrupt can wake the device from SLEEP. The user, in the interrupt service routine, can clear the interrupt in the following manner: a) b) 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. 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. Each of the PORTB pins has an internal pull-up, which can be individually enabled from the WPUB register. A single global enable bit can turn on/off the enabled pullups. Clearing the RBPU bit, (OPTION_REG<7>), REGISTER 3-2: R/W-1 WPUB7 bit7 bit 7-0: R/W-1 WPUB6 Any read or write of PORTB. This will end the mismatch condition. Clear flag bit RBIF. WEAK PULL UP PORTB REGISTER (WPUB: 95h) R/W-1 WPUB5 R/W-1 WPUB4 R/W-1 WPUB3 R/W-1 WPUB2 R/W-1 WPUB1 R/W-1 WPUB0 bit0 R = Readable bit W = Writable bit U = Unimplemented bit, read as `0' -n = Value at POR reset WPUB<7:0>: PORTB Weak Pull-Up Control 1 = Weak pull up enabled. 0 = Weak pull up disabled Note 1: For the WPUB register setting to take effect, the RBPU bit in the OPTION_REG Register must be cleared. 2: The weak pull up device is automatically disabled if the pin is in output mode (TRIS = 0). 1999 Microchip Technology Inc. Advanced Information DS41120A-page 35 PIC16C717/770/771 REGISTER 3-3: R/W-1 IOCB7 bit7 bit 7-0: R/W-1 IOCB6 INTERRUPT ON CHANGE PORTB REGISTER (IOCB: 96h) R/W-1 IOCB5 R/W-1 IOCB4 R/W-0 IOCB3 R/W-0 IOCB2 R/W-0 IOCB1 R/W-0 IOCB0 bit0 R = Readable bit W = Writable bit U = Unimplemented bit, read as `0' -n = Value at POR reset IOCB<7:0>: Interrupt on Change PORTB Control 1 = Interrupt on change enabled. 0 = Interrupt on change disabled. Note 1: The interrupt enable bits GIE and RBIE in the INTCON Register must be set for individual interrupts to be recognized. DS41120A-page 36 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 The RB0 pin is multiplexed with the A/D converter analog input 4 and the external interrupt input (RB0/AN4/ INT). When the pin is used as analog input, the ANSEL register must have the proper value to select the RB0 pin as analog mode. The RB1 pin is multiplexed with the A/D converter analog input 5 and the MSSP module slave select input (RB1/AN5/SS). When the pin is used as analog input, the ANSEL register must have the proper value to select the RB1 pin as analog mode. Note: FIGURE 3-7: Upon reset, the ANSEL register configures the RB1 and RB0 pins as analog inputs. Both RB1 and RB0 pins will read as '0'. BLOCK DIAGRAM OF RB0/AN4/INT, RB1/AN5/SS PIN Data Bus WR WPUB WPUB Reg D Q CK Q VDD RBPU P weak pull-up VDD PORTB Reg WR PORT D Q CK Q VDD P TRIS Reg WR TRIS D Q CK Q N VSS RD TRIS VSS Analog Select WR ANSEL D Q CK Q TTL IOCB Reg CK Q Q Set RBIF Schmitt Trigger Q ... D WR IOCB From RB<7:0> pins Q RD PORT D D EN Q EN EN D Q1 Q3 EN To INT input or MSSP module To A/D Converter 1999 Microchip Technology Inc. Advanced Information DS41120A-page 37 PIC16C717/770/771 FIGURE 3-8: BLOCK DIAGRAM OF RB2/SCK/SCL, RB3/CCP1/P1A, RB4/SDI/SDA, RB5/SDO/P1B Data Bus WPUB Reg D Q CK Q WR WPUB VDD Spec. Func En. RBPU P weak pull-up SDA, SDO, SCK, CCPL, P1A, P1B PORTB Reg WR PORT D Q CK Q VDD VDD 1 0 P N TRIS Reg WR TRIS D Q CK Q VSS VSS RD TRIS TTL IOCB Reg WR IOCB CK Schmitt Trigger Q Q Set RBIF Q ... D From RB<7:0> pins Q EN Q1 D Q RD PORT D EN EN D Q3 EN SCK, SCL, CC, SDI, SDA inputs DS41120A-page 38 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 FIGURE 3-9: BLOCK DIAGRAM OF RB6/T1OSO/T1CKI/P1C WPUB Reg Data Bus WR WPUB D Q CK Q VDD RBPU P weak pull-up VDD D Q P VDD WR PORTB CK Q Data Latch WR TRISB D Q CK Q N TRIS Latch VSS TTL Input Buffer RD TRISB T1OSCEN RD PORTB IOCB Reg D Q CK Q WR IOCB TMR1 Clock Serial programming clock Schmitt Trigger From RB7 TMR1 Oscillator Q D EN Q1 ... Set RBIF Q From RB<7:0> pins D EN RD Port Q3 Note: The TMR1 oscillator enable (T1OSCEN = 1) overrides the RB6 I/O port and P1C functions. 1999 Microchip Technology Inc. Advanced Information DS41120A-page 39 PIC16C717/770/771 FIGURE 3-10: BLOCK DIAGRAM OF THE RB7/T1OSI/P1D VDD RBPU WPUB Reg Data Bus WR WPUB D Q CK Q P weak pull-up To RB6 TMR1 Oscillator T1OSCEN VDD VDD D Q WR PORTB CK P Q Data Latch D Q WR TRISB CK N Q TRIS Latch VSS RD TRISB T10SCEN TTL Input Buffer RD PORTB IOCB Reg WR IOCB D Q CK Q Serial programming input Q Schmitt Trigger D EN Q1 ... Set RBIF From RB<7:0> pins Q D EN RD Port Q3 Note: The TMR1 oscillator enable (T1OSCEN = 1) overrides the RB7 I/O port and P1D functions. DS41120A-page 40 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 TABLE 3-3: PORTB FUNCTIONS Name RB0/AN4/INT RB1/AN5/SS RB2/SCK/SCL RB3/CCP1/P1A Function Input Type Output Type RB0 TTL CMOS AN4 AN A/D input INT ST Interrupt input RB1 TTL AN5 AN A/D input SS ST SSP slave select input RB2 TTL CMOS SCK ST CMOS Serial clock I/O for SPI SCL ST OD Serial clock I/O for I2C RB3 TTL CMOS Bi-directional input(1) CCP1 ST CMOS Capture 1 input/Compare 1 output CMOS P1A RB4/SDI/SDA RB5/SDO/P1B Address PWM P1A output CMOS Bi-directional input(1) SDA ST OD RB5 ST CMOS Bi-directional I/O(1) CMOS Serial data out for SPI Serial data in for SPI SDO TTL T1OSO T1CKI Serial data I/O for I2C CMOS PWM P1B output CMOS Bi-directional I/O(1) XTAL Crystal/Resonator ST TMR1 clock input RB7 TTL T1OSI XTAL CMOS PWM P1C output CMOS Bi-directional I/O(1) TMR1 crystal/resonator CMOS PWM P1D output SUMMARY OF REGISTERS ASSOCIATED WITH PORTB Name 06h, 106h PORTB 86h, 186h TRISB CMOS ST P1D Bit programmable pull-ups. TABLE 3-4: Bi-directional input(1) SDI P1C Note 1: Bi-directional I/O(1) TTL P1B RB7/T1OSI/P1D Bi-directional I/O(1) RB4 RB6 RB6/T1OSO/T1CKI/P1C Description Value on: POR, BOR Value on all other resets Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 RB7 RB6 RB5 RB4 RB3 RB2 RB1 RB0 xxxx xx00 uuuu uu00 PS0 1111 1111 1111 1111 1111 1111 1111 1111 PORTB Data Direction Register 81h, 181h OPTION_REG RBPU INTEDG T0CS T0SE PSA PS2 PS1 95h WPUB PORTB Weak Pull-up Control 1111 1111 1111 1111 96h IOCB PORTB Interrupt on Change Control 1111 0000 1111 0000 9Dh ANSEL ANS5 ANS4 ANS3 ANS2 ANS1 ANS0 1111 1111 1111 1111 Legend: x = unknown, u = unchanged. Shaded cells are not used by PORTB. 1999 Microchip Technology Inc. Advanced Information DS41120A-page 41 PIC16C717/770/771 NOTES: DS41120A-page 42 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 4.0 PROGRAM MEMORY READ (PMR) When interfacing the program memory block, the PMDATH & PMDATL registers form a 2-byte word, which holds the 14-bit data. The PMADRH & PMADRL registers form a 2-byte word, which holds the 12-bit address of the program memory location being accessed. Mid-range devices have up to 8K words of program EPROM with an address range from 0h to 3FFFh. When the device contains less memory than the full address range of the PMADRH:PMARDL registers, the most significant bits of the PMADRH register are ignored. Program memory is readable during normal operation (full VDD range). It is indirectly addressed through the Special Function Registers: * * * * * PMCON1 PMDATH PMDATL PMADRH PMADRL 4.0.1 PMCON1 REGISTER PMCON1 is the control register for program memory accesses. Control bit RD initiates a read operation. This bit cannot be cleared, only set, in software. It is cleared in hardware at completion of the read operation. REGISTER 4-1: PROGRAM MEMORY READ CONTROL REGISTER 1 (PMCON1: 18Ch) R-1 U-0 U-0 U-0 U-0 U-0 U-0 R/S-0 Reserved -- -- -- -- -- -- RD bit7 bit 7: bit0 R = Readable bit W = Writable bit S = Settable bit U = Unimplemented bit, read as `0' - n = Value at POR reset Reserved: Read as `1' bit 6-1: Unimplemented: Read as '0' bit 0: 4.0.2 RD: Read Control bit 1 = Initiates a Program memory read (read takes 2 cycles. RD is cleared in hardware. 0 = Reserved PMDATH AND PMDATL REGISTERS The PMDATH:PMDATL registers are loaded with the contents of program memory addressed by the PMADRH and PMADRL registers upon completion of a Program Memory Read command. 1999 Microchip Technology Inc. Advanced Information DS41120A-page 43 PIC16C717/770/771 REGISTER 4-2: PROGRAM MEMORY DATA HIGH (PMDATH: 10Eh) U-0 U-0 R-x R-x R-x R-x R-x R-x -- -- PMD13 PMD12 PMD11 PMD10 PMD9 PMD8 bit7 bit0 R = Readable bit W = Writable bit S = Settable bit U = Unimplemented bit, read as `0' - n = Value at POR reset bit 7-6: Unimplemented: Read as '0' bit 5-0: PMD<13:8>: The value of the program memory word pointed to by PMADRH and PMADRL after a program memory read command. REGISTER 4-3: PROGRAM MEMORY DATA LOW (PMDATL: 10Ch) R-x R-x R-x R-x R-x R-x R-x R-x PMD7 PMD6 PMD5 PMD4 PMD3 PMD2 PMD1 PMD0 bit7 bit0 R = Readable bit W = Writable bit S = Settable bit U = Unimplemented bit, read as `0' - n = Value at POR reset bit 7-0: PMD<7:0>: The value of the program memory word pointed to by PMADRH and PMADRL after a program memory read command. REGISTER 4-4: PROGRAM MEMORY ADDRESS HIGH (PMADRH: 10Fh) U-0 U-0 U-0 U-0 R/W-x R/W-x R/W-x R/W-x -- -- -- -- PMA11 PMA10 PMA9 PMA8 bit7 bit0 R = Readable bit W = Writable bit S = Settable bit U = Unimplemented bit, read as `0' - n = Value at POR reset bit 7-4: Unimplemented: Read as '0' bit 3-0: PMA<11:8>: PMR Address bits REGISTER 4-5: PROGRAM MEMORY ADDRESS LOW (PMADRL: 10Dh) R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x R/W-x PMA7 PMA6 PMA5 PMA4 PMA3 PMA2 PMA1 PMA0 bit7 bit0 R = Readable bit W = Writable bit S = Settable bit U = Unimplemented bit, read as `0' - n = Value at POR reset bit 7-0: PMA<7:0>: PMR Address bits DS41120A-page 44 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 4.0.3 READING THE EPROM PROGRAM MEMORY To read a program memory location, the user must write 2 bytes of the address to the PMADRH and PMADRL registers, then set control bit RD (PMCON1<0>). Once the read control bit is set, the Program Memory Read (PMR) controller will use the second instruction cycle after to read the data. This EXAMPLE 4-1: OTP PROGRAM MEMORY READ BSF STATUS, RP1 BCF STATUS, RP0 MOVLW MS_PROG_PM_ADDR MOVWF PMADRH MOVLW LS_PROG_PM_ADDR MOVWF PMADRL BSF STATUS, RP0 BSF PMCON1, RD NOP NOP next instruction 4.0.4 causes the second instruction immediately following the "BSF PMCON1,RD" instruction to be ignored. The data is available, in the very next cycle, in the PMDATH and PMDATL registers; therefore it can be read as 2 bytes in the following instructions. PMDATH and PMDATL registers will hold this value until another read or until it is written to by the user. ; ; ; ; ; ; ; ; ; ; ; Bank 2 MS Byte of Program Memory Address to read LS Byte of Program Memory Address to read Bank 3 Program Memory Read This instruction is executed This instruction must be a NOP PMDATH:PMDATL now has the data OPERATION DURING CODE PROTECT When the device is code protected, the CPU can still perform the program memory read function. FIGURE 4-1: PROGRAM MEMORY READ CYCLE EXECUTION Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Program Memory ADDR PC INSTR(PC-1) Executed here PC+1 BSF PMCON1,RD Executed here PMADRH,PMADRL PC+3 PC+4 PC+5 INSTR(PC+1) Executed here Forced NOP Executed here INSTR(PC+3) Executed here INSTR(PC+4) Executed here RD bit PMDATH PMDATL register 1999 Microchip Technology Inc. Advanced Information DS41120A-page 45 PIC16C717/770/771 NOTES: DS41120A-page 46 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 5.0 TIMER0 MODULE Additional information on external clock requirements is available in the PICmicroTM Mid-Range Reference Manual, (DS33023). The Timer0 module timer/counter has the following features: * * * * * * 5.2 8-bit timer/counter Readable and writable Internal or external clock select Edge select for external clock 8-bit software programmable prescaler Interrupt on overflow from FFh to 00h An 8-bit counter is available as a prescaler for the Timer0 module, or as a postscaler for the Watchdog Timer, respectively (Figure 5-2). For simplicity, this counter is being referred to as "prescaler" throughout this data sheet. Note that there is only one prescaler available which is mutually exclusively shared between the Timer0 module and the Watchdog Timer. Thus, a prescaler assignment for the Timer0 module means that there is no prescaler for the Watchdog Timer, and vice-versa. Figure 5-1 is a simplified block diagram of the Timer0 module. Additional information on timer modules is available in the PICmicroTM Mid-Range Reference Manual, (DS33023). 5.1 The prescaler is not readable or writable. The PSA and PS<2:0> bits (OPTION_REG<3:0>) determine the prescaler assignment and prescale ratio. Timer0 Operation Timer0 can operate as a timer or as a counter. Clearing bit PSA will assign the prescaler to the Timer0 module. When the prescaler is assigned to the Timer0 module, prescale values of 1:2, 1:4, ..., 1:256 are selectable. Timer mode is selected by clearing bit T0CS (OPTION_REG<5>). In timer mode, the Timer0 module will increment every instruction cycle (without prescaler). If the TMR0 register is written, 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. Setting bit PSA will assign the prescaler to the Watchdog Timer (WDT). When the prescaler is assigned to the WDT, prescale values of 1:1, 1:2, ..., 1:128 are selectable. Counter mode is selected by setting bit T0CS (OPTION_REG<5>). In counter mode, Timer0 will increment either on every rising or falling edge of pin RA4/T0CKI. The incrementing edge is determined by the Timer0 Source Edge Select bit T0SE (OPTION_REG<4>). Clearing bit T0SE selects the rising edge. Restrictions on the external clock input are discussed in below. When assigned to the Timer0 module, all instructions writing to the TMR0 register (e.g. CLRF 1, MOVWF 1, BSF 1, x....etc.) will clear the prescaler. When assigned to WDT, a CLRWDT instruction will clear the prescaler along with the WDT. Note: When an external clock input is used for Timer0, it must meet certain requirements. The requirements ensure the external clock can be synchronized with the internal phase clock (TOSC). Also, there is a delay in the actual incrementing of Timer0 after synchronization. FIGURE 5-1: Prescaler Writing to TMR0 when the prescaler is assigned to Timer0 will clear the prescaler count, but will not change the prescaler assignment. TIMER0 BLOCK DIAGRAM Data Bus FOSC/4 0 PSout 1 1 Programmable Prescaler RA4/T0CKI pin 0 8 Sync with Internal clocks TMR0 PSout (2 TCY delay) T0SE 3 PS2, PS1, PS0 PSA T0CS Set interrupt flag bit T0IF on overflow Note 1: T0CS, T0SE, PSA, PS<2:0> (OPTION_REG<5:0>). 2: The prescaler is shared with Watchdog Timer (refer to Figure 5-2 for detailed block diagram). 1999 Microchip Technology Inc. Advanced Information DS41120A-page 47 PIC16C717/770/771 5.2.1 5.3 SWITCHING PRESCALER ASSIGNMENT The prescaler assignment is fully under software control, i.e., it can be changed "on-the-fly" during program execution. Note: The TMR0 interrupt is generated when the TMR0 register overflows from FFh to 00h. This overflow sets bit T0IF (INTCON<2>). The interrupt can be masked by clearing bit T0IE (INTCON<5>). Bit T0IF must be cleared in software by the Timer0 module interrupt service routine before re-enabling this interrupt. The TMR0 interrupt cannot awaken the processor from SLEEP since the timer is shut off during SLEEP. To avoid an unintended device RESET, a specific instruction sequence (shown in the PICmicroTM Mid-Range Reference Manual, DS33023) must be executed when changing the prescaler assignment from Timer0 to the WDT. This sequence must be followed even if the WDT is disabled. FIGURE 5-2: Timer0 Interrupt BLOCK DIAGRAM OF THE TIMER0/WDT PRESCALER Data Bus CLKOUT (= FOSC/4) 0 RA4/T0CKI Pin 8 M U X 1 M U X 0 1 SYNC 2 Cycles TMR0 reg T0SE T0CS 0 1 Watchdog Timer Set flag bit T0IF on Overflow PSA 8-bit Prescaler M U X 8 8 - to - 1MUX PS<2:0> PSA 1 0 WDT Enable Bit MUX PSA WDT Time-out Note: T0CS, T0SE, PSA, PS<2:0> are (OPTION_REG<5:0>). TABLE 5-1: REGISTERS ASSOCIATED WITH TIMER0 Address Name Bit 7 Bit 6 Bit 5 Bit 4 01h,101h TMR0 0Bh,8Bh, 10Bh,18Bh INTCON 81h,181h OPTION_REG RBPU INTEDG 85h TRISA PORTA Data Direction Register Bit 3 Bit 2 Bit 1 Bit 0 Timer0 register GIE PEIE Value on: POR, BOR Value on all other resets xxxx xxxx uuuu uuuu T0IE INTE RBIE T0IF INTF RBIF 0000 000x 0000 000u T0CS T0SE PSA PS2 PS1 PS0 1111 1111 1111 1111 1111 1111 1111 1111 Legend: x = unknown, u = unchanged, - = unimplemented locations read as '0'. Shaded cells are not used by Timer0. DS41120A-page 48 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 6.0 TIMER1 MODULE 6.1 The Timer1 module timer/counter has the following features: * 16-bit timer/counter (Two 8-bit registers; TMR1H and TMR1L) * Readable and writable (Both registers) * Internal or external clock select * Interrupt on overflow from FFFFh to 0000h * Reset from ECCP module trigger Figure 6-2 is a simplified block diagram of the Timer1 module. Additional information on timer modules is available in the PICmicroTM Mid-Range Reference Manual, (DS33023). U-0 U-0 -- -- Timer1 can operate in one of these modes: * As a timer * As a synchronous counter * As an asynchronous counter The operating mode is determined by the clock select bit, TMR1CS (T1CON<1>). Timer1 has a control register, shown in Register 6-1. Timer1 can be enabled/disabled by setting/clearing control bit TMR1ON (T1CON<0>). REGISTER 6-1: Timer1 Operation In timer mode, Timer1 increments every instruction cycle. In counter mode, it increments on every rising edge of the external clock input. When the Timer1 oscillator is enabled (T1OSCEN is set), the RB7/T1OSI/P1D and RB6/T1OSO/T1CKI/ P1C pins are no longer available as I/O ports or PWM outputs. That is, the TRISB<7:6> value is ignored. Timer1 also has an internal "reset input". This reset can be generated by the ECCP module (Section 7.0). TIMER1 CONTROL REGISTER (T1CON: 10h) R/W-0 R/W-0 R/W-0 T1CKPS1 T1CKPS0 T1OSCEN R/W-0 T1SYNC R/W-0 R/W-0 TMR1CS TMR1ON bit7 bit0 R = Readable bit W = Writable bit U = Unimplemented bit, read as `0' - n = Value at POR reset bit 7-6: Unimplemented: Read as '0' 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: T1OSCEN: Timer1 Oscillator Enable Control bit 1 = Oscillator is enabled 0 = Oscillator is shut off Note: The oscillator inverter and feedback resistor are turned off to eliminate power drain bit 2: T1SYNC: Timer1 External Clock Input Synchronization Control bit TMR1CS = 1 1 = Do not synchronize external clock input 0 = Synchronize external clock input TMR1CS = 0 This bit is ignored. Timer1 uses the internal clock when TMR1CS = 0. bit 1: TMR1CS: Timer1 Clock Source Select bit 1 = External clock from pin RB6/T1OSO/T1CKI /P1C(on the rising edge) 0 = Internal clock (FOSC/4) bit 0: TMR1ON: Timer1 On bit 1 = Enables Timer1 0 = Stops Timer1 1999 Microchip Technology Inc. Advanced Information DS41120A-page 49 PIC16C717/770/771 6.1.1 TIMER1 COUNTER OPERATION In this mode, Timer1 is being incremented via an external source. Increments occur on a rising edge. After Timer1 is enabled in counter mode, the module must first have a falling edge before the counter begins to increment. FIGURE 6-1: TIMER1 INCREMENTING EDGE T1CKI (Initially high) First falling edge of the T1ON enabled T1CKI (Initially low) First falling edge of the T1ON enabled Note: Arrows indicate counter increments. FIGURE 6-2: TIMER1 BLOCK DIAGRAM Set flag bit TMR1IF on Overflow 0 TMR1 TMR1H Synchronized clock input TMR1L 1 TMR1ON on/off T1SYNC T1OSC RB6/T1OSO/T1CKI/P1C RB7/T1OSI/P1D 1 T1OSCEN FOSC/4 Enable Internal Oscillator(1) Clock Prescaler 1, 2, 4, 8 Synchronize det 0 2 T1CKPS<1:0> TMR1CS SLEEP input Note 1: When the T1OSCEN bit is cleared, the inverter and feedback resistor are turned off. This eliminates power drain. DS41120A-page 50 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 6.2 6.3 Timer1 Oscillator A crystal oscillator circuit is built in between pins T1OSI (input) and T1OSO (amplifier output). It is enabled by setting control bit T1OSCEN (T1CON<3>). The oscillator is a low power oscillator rated up to 200 kHz. It will continue to run during SLEEP. It is primarily intended for a 32 kHz crystal. Table 6-1 shows the capacitor selection for the Timer1 oscillator. The Timer1 oscillator is identical to the LP oscillator. The user must provide a software time delay to ensure proper oscillator start-up. TABLE 6-1: CAPACITOR SELECTION FOR THE TIMER1 OSCILLATOR Osc Type Freq C1 C2 LP 32 kHz 100 kHz 200 kHz 33 pF 15 pF 15 pF 33 pF 15 pF 15 pF Timer1 Interrupt The TMR1 Register pair (TMR1H:TMR1L) increments from 0000h to FFFFh and rolls over to 0000h. The TMR1 Interrupt, if enabled, is generated on overflow which is latched in interrupt flag bit TMR1IF (PIR1<0>). This interrupt can be enabled/disabled by setting/clearing TMR1 interrupt enable bit TMR1IE (PIE1<0>). 6.4 Resetting Timer1 using a CCP Trigger Output If the ECCP module is configured in compare mode to generate a "special event trigger" (CCP1M<3:0> = 1011), this signal will reset Timer1 and start an A/D conversion (if the A/D module is enabled). Note: These values are for design guidance only. 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. The special event triggers from the CCP1 module will not set interrupt flag bit TMR1IF (PIR1<0>). Timer1 must be configured for either timer or synchronized counter mode to take advantage of this feature. If Timer1 is running in asynchronous counter mode, this reset operation may not work. In the event that a write to Timer1 coincides with a special event trigger from ECCP1, the write will take precedence. In this mode of operation, the CCPR1H:CCPR1L registers pair effectively becomes the period register for Timer1. TABLE 6-2: REGISTERS ASSOCIATED WITH TIMER1 AS A TIMER/COUNTER Address Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Value on: POR, BOR Value on all other resets 0Bh,8Bh, 10Bh,18Bh INTCON GIE PEIE T0IE INTE RBIE T0IF INTF RBIF 0000 000x 0000 000u -0-- 0000 0Ch PIR1 -- ADIF -- -- SSPIF CCP1IF TMR2IF TMR1IF -0-- 0000 8Ch PIE1 -- ADIE -- -- SSPIE CCP1IE TMR2IE TMR1IE -0-- 0000 -0-- 0000 uuuu uuuu 0Eh TMR1L Holding register for the Least Significant Byte of the 16-bit TMR1 register xxxx xxxx 0Fh TMR1H Holding register for the Most Significant Byte of the 16-bit TMR1 register xxxx xxxx uuuu uuuu 10h T1CON --00 0000 --uu uuuu Legend: -- -- T1CKPS1 T1CKPS0 T1OSCEN T1SYNC TMR1CS TMR1ON x = unknown, u = unchanged, - = unimplemented read as '0'. Shaded cells are not used by the Timer1 module. 1999 Microchip Technology Inc. Advanced Information DS41120A-page 51 PIC16C717/770/771 NOTES: DS41120A-page 52 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 7.0 TIMER2 MODULE 7.1 The Timer2 module timer has the following features: * * * * * * * Timer2 Operation Timer2 can be used as the PWM time-base for PWM mode of the ECCP module. 8-bit timer (TMR2 register) 8-bit period register (PR2) Readable and writable (Both registers) Software programmable prescaler (1:1, 1:4, 1:16) Software programmable postscaler (1:1 to 1:16) Interrupt on TMR2 match of PR2 SSP module optional use of TMR2 output to generate clock shift The TMR2 register is readable and writable, and is 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 T2CKPS<1:0> (T2CON<1:0>). Timer2 has a control register, shown in Register 7-1. Timer2 can be shut off by clearing control bit TMR2ON (T2CON<2>) to minimize power consumption. Figure 7-1 is a simplified block diagram of the Timer2 module. Additional information on timer modules is available in the PICmicroTM Mid-Range Reference Manual, (DS33023). The match output of TMR2 goes through a 4-bit postscaler (which gives a 1:1 to 1:16 scaling inclusive) to generate a TMR2 interrupt (latched in flag bit TMR2IF, (PIR1<1>)). The prescaler and postscaler counters are cleared when any of the following occurs: * a write to the TMR2 register * a write to the T2CON register * any device reset (Power-on Reset, MCLR Reset, Watchdog Timer Reset, or Brown-out Reset) TMR2 is not cleared when T2CON is written. REGISTER 7-1: U-0 -- R/W-0 TIMER2 CONTROL REGISTER (T2CON1: 12h) R/W-0 R/W-0 R/W-0 R/W-0 TOUTPS3 TOUTPS2 TOUTPS1 TOUTPS0 TMR2ON R/W-0 bit7 bit 7: R/W-0 T2CKPS1 T2CKPS0 bit0 R = Readable bit W = Writable bit U = Unimplemented bit, read as `0' - n = Value at POR reset Unimplemented: Read as '0' bit 6-3: TOUTPS<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: 2CKPS<1:0>: Timer2 Clock Prescale Select bits 00 = Prescaler is 1 01 = Prescaler is 4 1x = Prescaler is 16 1999 Microchip Technology Inc. Advanced Information DS41120A-page 53 PIC16C717/770/771 7.2 Timer2 Interrupt FIGURE 7-1: Sets flag bit TMR2IF The Timer2 module has an 8-bit period register PR2. Timer2 increments from 00h until it matches PR2 and then resets to 00h on the next increment cycle. PR2 is a readable and writable register. The PR2 register is initialized to FFh upon reset. 7.3 TIMER2 BLOCK DIAGRAM TMR2 output (1) Reset Postscaler 1:1 to 1:16 Output of TMR2 The output of TMR2 (before the postscaler) is fed to the Synchronous Serial Port module which optionally uses it to generate shift clock. EQ 4 TMR2 reg Prescaler 1:1, 1:4, 1:16 FOSC/4 2 Comparator PR2 reg Note 1: TMR2 register output can be software selected by the SSP Module as a baud clock. TABLE 7-1: Address Name 0Bh,8Bh, INTCON 10Bh,18Bh 0Ch PIR1 8Ch PIE1 11h TMR2 12h T2CON 92h PR2 Legend: REGISTERS ASSOCIATED WITH TIMER2 AS A TIMER/COUNTER Value on: POR, BOR Value on all other resets Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 GIE PEIE T0IE INTE RBIE T0IF INTF RBIF 0000 000x 0000 000u -- ADIF -- -- SSPIF CCP1IF TMR2IF TMR1IF -0-- 0000 -0-- 0000 -- ADIE -- -- SSPIE CCP1IE TMR2IE TMR1IE -0-- 0000 -0-- 0000 0000 0000 0000 0000 Timer2 register -- TOUTPS3 TOUTPS2 TOUTPS1 TOUTPS0 TMR2ON T2CKPS1 T2CKPS0 -000 0000 -000 0000 1111 1111 1111 1111 Timer2 Period Register x = unknown, u = unchanged, - = unimplemented read as '0'. Shaded cells are not used by the Timer2 module. DS41120A-page 54 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 8.0 ENHANCED CAPTURE/ COMPARE/PWM(ECCP) MODULES The ECCP (Enhanced Capture/Compare/PWM) module contains a 16-bit register which can operate as a 16-bit capture register, as a 16-bit compare register or as a PWM master/slave Duty Cycle register. Table 8-1 shows the timer resources of the ECCP module modes. REGISTER 8-1: Capture/Compare/PWM Register1 (CCPR1) is comprised of two 8-bit registers: CCPR1L (low byte) and CCPR1H (high byte). The CCP1CON and P1DEL registers control the operation of ECCP. All are readable and writable. CCP1 CONTROL REGISTER (CCP1CON: 17h) R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 PWM1M1 PWM1M0 DC1B1 DC1B0 CCP1M3 CCP1M2 CCP1M1 CCP1M0 bit7 bit0 R = Readable bit W= Writable bit U = Unimplemented bit, read as `0' - n = Value at POR reset bit 7-6: PWM1M<1:0>: PWM Output Configuration IF CCP1M<3:2> = 00, 01, 10 xx - P1A assigned as Capture/Compare input. P1B, P1C, P1D assigned as Port pins. IF CCP1M<3:2> = 11 00 - Single output. P1A modulated. P1B, P1C, P1D assigned as Port pins. 01 - Full-bridge output forward. P1D modulated. P1A active. P1B, P1C inactive. 10 - Half-bridge output. P1A, P1B modulated with deadband control. P1C, P1D assigned as Port pins. 11 - Full-bridge output reverse. P1B modulated. P1C active. P1A, P1D inactive. bit 5-4: DC1B<1:0>: PWM Duty Cycle Least Significant bits Capture Mode: Unused Compare Mode: Unused PWM Mode: These bits are the two LSbs of the PWM duty cycle. The eight MSbs are found in CCPRnL. bit 3-0: CCP1M<3:0>: ECCP1 Mode Select bits 0000 = Capture/Compare/PWM off (resets ECCP module) 0001 = Unused (reserved) 0010 = Compare mode, toggle output on match (CCP1IF bit is set) 0011 = Unused (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, set output on match (CCP1IF bit is set) 1001 = Compare mode, clear output on match (CCP1IF bit is set) 1010 = Compare mode, generate software interrupt on match (CCP1IF bit is set, CCP1 pin is unaffected) 1011 = Compare mode, trigger special event (CCP1IF bit is set; ECCP resets TMR1, and starts an A/D conversion, if the A/D module is enabled.) 1100 = PWM mode. P1A, P1C active high. P1B, P1D active high. 1101 = PWM mode. P1A, P1C active high. P1B, P1D active low. 1110 = PWM mode. P1A, P1C active low. P1B, P1D active high. 1111 = PWM mode. P1A, P1C active low. P1B, P1D active low. 1999 Microchip Technology Inc. Advanced Information DS41120A-page 55 PIC16C717/770/771 TABLE 8-1: ECCP MODE - TIMER RESOURCE ECCP1 Mode Timer Resource Capture Compare PWM Timer1 Timer1 Timer2 8.1 Capture Mode EXAMPLE 8-1: CLRF MOVLW MOVWF CCP1CON, F ; Turn ECCP module off NEW_CAPT_PS ; Load WREG with the ; new prescaler mode ; value and ECCP ON CCP1CON ; Load CCP1CON with ; this value FIGURE 8-1: In Capture mode, CCPR1H:CCPR1L captures the 16bit value of the TMR1 register when an event occurs on pin CCP1. An event is defined as: * * * * every falling edge every rising edge every 4th rising edge every 16th rising edge 8.1.2 CCP1 PIN CONFIGURATION If the RB3/CCP1/P1A 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 bit CCP1IE (PIE1<2>) clear to avoid false interrupts and should clear the flag bit CCP1IF following any such change in operating mode. 8.1.4 ECCP PRESCALER There are four prescaler settings, specified by bits CCP1M<3:0>. Whenever the ECCP module is turned off or the ECCP1 module is not in capture mode, 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 8-1 shows the recommended method for switching between capture prescalers. This example also clears the prescaler counter and will not generate the "false" interrupt. DS41120A-page 56 Set flag bit CCP1IF (PIR1<2>) CCPR1H CCPR1L Capture Enable TMR1H TMR1L CCP1CON<3:0> Q's 8.2 Compare Mode In Compare mode, the 16-bit CCPR1 register value is constantly compared against the TMR1 register pair value. When a match occurs, the CCP1 pin is: * * * * driven High driven Low toggle output (High to Low or Low to High) remains Unchanged The action on the pin is based on the value of control bits CCP1M<3:0>. At the same time, interrupt flag bit CCP1IF is set. TIMER1 MODE SELECTION Timer1 must be running in timer mode or synchronized counter mode. In asynchronous counter mode, the capture operation may not work. 8.1.3 Prescaler / 1, 4, 16 and edge detect In Capture mode, the CCP1 pin should be configured as an input by setting the TRISB<3> bit. Note: CAPTURE MODE OPERATION BLOCK DIAGRAM RB3/CCP1/ P1A Pin An event is selected by control bits CCP1M<3:0> (CCP1CON<3:0>). When a capture is made, the interrupt request flag bit CCP1IF (PIR1<2>) is set. It must be cleared in software. If another capture occurs before the value in register CCPR1 is read, the old captured value will be lost. 8.1.1 CHANGING BETWEEN CAPTURE PRESCALERS 8.2.1 CCP1 PIN CONFIGURATION The user must configure the CCP1 pin as an output by clearing the appropriate TRISB bit. Note: 8.2.2 Clearing the CCP1CON register will force the CCP1 compare output latch to the default low level. This is not the port data latch. TIMER1 MODE SELECTION Timer1 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 may not work. 8.2.3 SOFTWARE INTERRUPT MODE When generate software interrupt is chosen, the CCP1 pin is not affected. Only an ECCP interrupt is generated (if enabled). Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 8.2.4 SPECIAL EVENT TRIGGER FIGURE 8-2: In this mode, an internal hardware trigger is generated, which may be used to initiate an action. The special event trigger output of ECCP resets the TMR1 register pair. This allows the CCPR1 register to effectively be a 16-bit programmable period register for Timer1. Special event trigger will: reset Timer1, but not set interrupt flag bit TMR1IF (PIR1<0>). The special event trigger output of ECCP module will also start an A/D conversion if the A/D module is enabled. Note: The special event trigger will not set the interrupt flag bit TMR1IF (PIR1<0>). TABLE 8-2: Name INTCON COMPARE MODE OPERATION BLOCK DIAGRAM Special Event Trigger Set flag bit CCP1IF (PIR1<2>) CCPR1H CCPR1L Q S Output Logic match RB3/CCP1/ R P1A Pin TRISB<3> Output Enable CCP1CON<3:0> Mode Select Comparator TMR1H TMR1L REGISTERS ASSOCIATED WITH CAPTURE, COMPARE AND TIMER1 Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Value on POR, BOR Value on all other resets GIE PEIE T0IE INTE RBIE T0IF INTF RBIF 0000 000x 0000 000u PIR1 PSPIF(1) ADIF RCIF TXIF SSPIF CCP1IF TMR2IF TMR1IF 0000 0000 0000 0000 PIE1 PSPIE(1) ADIE RCIE TXIE SSPIE CCP1IE TMR2IE TMR1IE 0000 0000 0000 0000 TRISB PORTB Data Direction Register 1111 1111 1111 1111 TMR1L Holding register for the Least Significant Byte of the 16-bit TMR1 register xxxx xxxx uuuu uuuu TMR1H Holding register for the Most Significant Byte of the 16-bit TMR1register xxxx xxxx uuuu uuuu --00 0000 --uu uuuu xxxx xxxx uuuu uuuu xxxx xxxx uuuu uuuu 0000 0000 0000 0000 T1CON -- -- T1CKPS1 T1CKPS0 CCPR1L Capture/Compare/PWM register1 (LSB) CCPR1H Capture/Compare/PWM register1 (MSB) CCP1CON PWM1M1 Legend: PWM1M0 DC1B1 DC1B0 T1OSCEN CCP1M3 T1SYNC CCP1M2 TMR1CS CCP1M1 TMR1ON CCP1M0 x = unknown, u = unchanged, - = unimplemented read as '0'. Shaded cells are not used by Capture and Timer1. 1999 Microchip Technology Inc. Advanced Information DS41120A-page 57 PIC16C717/770/771 8.3 PWM Mode In Pulse Width Modulation (PWM) mode, the ECCP module produces up to a 10-bit resolution PWM output. Figure 8-3 shows the simplified PWM block diagram. FIGURE 8-3: SIMPLIFIED PWM BLOCK DIAGRAM CCP1CON<5:4> Duty cycle registers PWM1M1<1:0> CCP1M<3:0> 4 2 CCPR1L CCP1/P1A RB3/CCP1/P1A TRISB<3> CCPR1H (Slave) P1B R Comparator OUTPUT CONTROLLER Q RB5/SDO/P1B TRISB<5> RB6/T1OSO/T1CKI/ P1C P1C TMR2 (Note 1) TRISB<6> S P1D Comparator PR2 Clear Timer, CCP1 pin and latch D.C. RB7/T1OSI/P1D TRISB<7> P1DEL Note: 8-bit timer TMR2 is concatenated with 2-bit internal Q clock or 2 bits of the prescaler to create 10-bit time-base. 8.3.1 PWM PERIOD The PWM period is specified by writing to the PR2 register. The PWM period can be calculated using the following formula: PWM PERIOD = (PR2) + 1] * 4 * TOSC * (TMR2 PRESCALE VALUE) PWM frequency is defined as 1 / [PWM period]. When TMR2 is equal to PR2, the following three events occur on the next increment cycle: * TMR2 is cleared * The CCP1 pin is set (exception: if PWM duty cycle = 0%, the CCP1 pin will not be set) * The PWM duty cycle is latched from CCPR1L into CCPR1H Note: The Timer2 postscaler (see Section 7.0) is 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. DS41120A-page 58 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 8.3.2 PWM DUTY CYCLE FIGURE 8-4: The PWM duty cycle is specified by writing to the CCPR1L register and to the CCP1CON<5:4> bits. Up to 10-bit resolution is available. The CCPR1L contains the eight MSbs and the CCP1CON<5:4> contains the two LSbs. This 10-bit value is represented by CCPR1L:CCP1CON<5:4>. The following equation is used to calculate the PWM duty cycle in time: PWM duty cycle = (CCPR1L:CCP1CON<5:4>) * TOSC * (TMR2 prescale value) CCPR1L and CCP1CON<5:4> can be written to at any time, but the duty cycle value is not latched into CCPR1H until after a match between PR2 and TMR2 occurs (i.e., the period is complete). In PWM mode, CCPR1H is a read-only register. The CCPR1H 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 CCPR1H and 2-bit latch match TMR2 concatenated with an internal 2-bit Q clock or 2 bits of the TMR2 prescaler, the CCP1 pin is cleared. SINGLE PWM OUTPUT Period CCP1(2) Duty Cycle (1) (1) Note 1: At this time, the TMR2 register is equal to the PR2 register. 2: Output signal is shown as asserted high. FIGURE 8-5: EXAMPLE OF SINGLE OUTPUT APPLICATION PIC16C717/770/771 Using PWM as a D/A Converter R CCP1 VOUT Maximum PWM resolution (bits) for a given PWM frequency: C F OSC log --------------- F PWM = ----------------------------- bits log ( 2 ) V+ PIC16C717/770/771 Note: 8.3.3 If the PWM duty cycle value is longer than the PWM period, the CCP1 pin will not be cleared. CCP1 PWM OUTPUT CONFIGURATIONS The PWM1M1 bits in the CCP1CON register allows one of the following configurations: * * * * L O A D Using PWM to Drive a Power Load Single output Half-Bridge output Full-Bridge output, Forward mode Full-Bridge output, Reverse mode In the Single Output mode, the RB3/CCP1/P1A pin is used as the PWM output. Since the CCP1 output is multiplexed with the PORTB<3> data latch, the TRISB<3> bit must be cleared to make the CCP1 pin an output. In the Half-Bridge output mode, two pins are used as outputs. The RB3/CCP1/P1A pin has the PWM output signal, while the RB5/SDO/P1B pin has the complementary PWM output signal. This mode can be used for half-bridge applications, as shown on Figure 8-7, or for full-bridge applications, where four power switches are being modulated with two PWM signal. Since the P1A and P1B outputs are multiplexed with the PORTB<3> and PORTB<5> data latches, the TRISB<3> and TRISB<5> bits must be cleared to configure P1A and P1B as outputs. In Half-Bridge output mode, the programmable deadband delay can be used to prevent shoot-through current in bridge power devices. See Section 8.3.5 for more details of the deadband delay operations. 1999 Microchip Technology Inc. Advanced Information DS41120A-page 59 PIC16C717/770/771 8.3.4 OUTPUT POLARITY CONFIGURATION The CCP1M<1:0> bits in the CCP1CON register allow user to choose the logic conventions (asserted high/ low) for each of the outputs. See Register 8-1 for further details. FIGURE 8-6: The PWM output polarities must be selected before the PWM outputs are enabled. Charging the polarity configuration while the PWM outputs are active is not recommended, since it may result in unpredictable operation. HALF-BRIDGE PWM OUTPUT Period Period Duty Cycle (2) P1A td td P1B(2) (1) (1) (1) td = Deadband Delay Note 1: At this time, the TMR2 register is equal to the PR2 register. 2: Output signals are shown as asserted high. DS41120A-page 60 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 FIGURE 8-7: EXAMPLE OF HALF-BRIDGE OUTPUT MODE APPLICATIONS V+ PIC16C717/770/771 FET DRIVER + V - P1A + LOAD FET DRIVER + V - P1B V- V+ PIC16C717/770/771 FET DRIVER FET DRIVER P1A + FET DRIVER LOAD FET DRIVER P1B V- 1999 Microchip Technology Inc. Advanced Information DS41120A-page 61 PIC16C717/770/771 In Full-Bridge output mode, four pins are used as outputs; however, only two outputs are active at a time. In the Forward mode, RB3/CCP1/P1A pin is continuously active, and RB7/T1OSI/P1D pin is modulated. In the Reverse mode, RB6/T1OSO/T1CKI/P1C pin is continuously active, and RB5/SDO/P1B pin is modulated. FIGURE 8-8: P1A, P1B, P1C and P1D outputs are multiplexed with PORTB<3> and PORTB<5:7> data latches. TRISB<3> and TRISB<5:7> bits must be cleared to make the P1A, P1B, P1C, and P1D pins output. FULL-BRIDGE PWM OUTPUT FORWARD MODE Period P1A(2) 1 0 Duty Cycle P1B(2) 1 0 P1C(2) 1 0 P1D(2) 1 0 (1) (1) REVERSE MODE Period Duty Cycle P1A(2) 1 0 P1B(2) 1 0 P1C(2) 1 0 P1D(2) 1 0 (1) (1) Note 1: At this time, the TMR2 register is equal to the PR2 register. 2: Output signal is shown as asserted high. DS41120A-page 62 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 FIGURE 8-9: EXAMPLE OF FULL-BRIDGE APPLICATION V+ PIC16C717/770/771 FET DRIVER FET DRIVER P1D + LOAD P1C FET DRIVER FET DRIVER P1A VP1B 1999 Microchip Technology Inc. Advanced Information DS41120A-page 63 PIC16C717/770/771 8.3.5 PROGRAMMABLE DEADBAND DELAY In half-bridge or full-bridge applications, where all power switches are modulated at the PWM frequency at all time, the power switches normally require longer 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 will be on for a short period of time, until one switch completely turns off. During this time, a very high current, called shoot-through current, will flow through both power switches, shorting the bridge supply. To REGISTER 8-2: R/W-0 R/W-0 avoid this potentially destructive shoot-through current from flowing during switching, turning on the power switch is normally delayed to allow the other switch to completely turn off. In the Half-Bridge Output mode, a digitally programmable deadband delay is available to avoid shootthrough current from destroying the bridge power switches. The delay occurs at the signal transition from the non-active state to the active state. See Figure 8-6 for illustration. The P1DEL register sets the amount of delay. PWM DELAY REGISTER (P1DEL: 97H) R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 bit7 bit0 R = Readable bit W = Writable bit U = Unimplemented bit, read as `0' - n = Value at POR reset bit 7-0: P1DEL<7:0>: PWM Delay count for Half-Bridge output mode: Number of FOSC/4 (Tosc*4) cycles between the P1A transition and the P1B transition. 8.3.6 DIRECTION CHANGE IN FULL-BRIDGE OUTPUT MODE In the Full-Bridge Output mode, the PWM1M1 bit in the CCP1CON register allows user to control the Forward/ Reverse direction. When the application firmware changes this direction control bit, the ECCP module will assume the new direction on the next PWM cycle. The current PWM cycle still continues, however, the non- modulated outputs, P1A and P1C signals, will transition to the new direction TOSC, 4*TOSC or 16*TOSC (for Timer2 presale T2CKRS<1:0> = 00, 01 and 1x respectively) earlier, before the end of the period. During this transition cycle, the modulated outputs, P1B and P1D, will go to the inactive state. See Figure 8-10 for illustration. FIGURE 8-10: PWM DIRECTION CHANGE (1) SIGNAL PERIOD PERIOD DC P1A (Active High) P1B (Active High) P1C (Active High) P1D (Active High) Note 1: 2: (2) The Direction bit in the ECCP Control Register (CCP1CON.PWM1M1) is written anytime during the PWM cycle. The P1A and P1C signals switch TOSC, 4*Tosc or 16*TOSC depending on the Timer2 prescaler value earlier when changing direction. The modulated P1B and P1D signals are inactive at this time. DS41120A-page 64 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 Note that in the Full-Bridge output mode, the ECCP module does not provide any deadband delay. In general, since only one output is modulated at all time, deadband delay is not required. However, there is a situation where a deadband delay might be required. This situation occurs when all of the following conditions are true: 1. 2. 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 turn on time. example, since the turn off time of the power devices is longer than the turn on time, a shoot-through current flows through the power devices, QB and QD, for the duration of t= toff-ton. The same phenomenon will occur to power devices, QC and QB, for PWM direction change from reverse to forward. If changing PWM direction at high duty cycle is required for the user's application, one of the following requirements must be met: 1. 2. Figure 8-11 shows an example, where the PWM direction changes from forward to reverse at a near 100% duty cycle. At time t1, the output P1A and P1D become inactive, while output P1C becomes active. In this Avoid changing PWM output direction at or near 100% duty cycle. Use switch drivers that compensate the slow turn off of the power devices. The total turn off time (toff) of the power device and the driver must be less than the turn on time (ton). FIGURE 8-11: PWM DIRECTION CHANGE AT NEAR 100% DUTY CYCLE FORWARD PERIOD REVERSE PERIOD P1A 1 0 1 P1B 0 (PWM) 1 P1C 0 P1D 1 0 (PWM) ton 1 External Switch C 0 toff 1 External Switch D 0 Potential 1 Shoot Through 0 Current t = toff - ton t1 Note 1: All signals are shown as active high. 2: ton is the turn on delay of power switch and driver. 3: toff is the turn off delay of power switch and driver. 1999 Microchip Technology Inc. Advanced Information DS41120A-page 65 PIC16C717/770/771 8.3.7 SYSTEM IMPLEMENTATION 8.3.9 When the ECCP module is used in the PWM mode, the application hardware must use the proper external pullup and/or pull-down resistors on the PWM output pins. When the microcontroller powers up, all of the I/O pins are in the high-impedance state. The external pull-up and pull-down resistors 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). 8.3.8 The following steps should be taken when configuring the ECCP module for PWM operation: 1. START-UP CONSIDERATIONS Prior to enabling the PWM outputs, the P1A, P1B, P1C and P1D latches may not be in the proper states. Enabling the TRISB bits for output at the same time with the CCP module may cause damage to the power switch devices. The CCP1 module must be enabled in the proper output mode with the TRISB bits enabled as inputs. Once the CCP1 completes a full PWM cycle, the P1A, P1B, P1C and P1D output latches are properly initialized. At this time, the TRISB bits can be enabled for outputs to start driving the power switch devices. The completion of a full PWM cycle is indicated by the TMR2IF bit going from a '0' to a '1'. 2. 3. TABLE 8-3: Address Name 0Bh, 8Bh, 10Bh, 18Bh INTCON SET UP FOR PWM OPERATION Configure the PWM module: a) Disable the CCP1/P1A, P1B, P1C and/or P1D outputs by setting the respective TRISB bits. b) Set the PWM period by loading the PR2 register. c) Set the PWM duty cycle by loading the CCPR1L register and CCP1CON<5:4> bits. d) Configure the ECCP module for the desired PWM operation by loading the CCP1CON register. With the CCP1M<3:0> bits select the active high/low levels for each PWM output. With the PWM1M<1:0> bits select one of the available output modes: Single, Half-Bridge, Full-Bridge, Forward or FullBridge Reverse. e) For Half-Bridge output mode, set the deadband delay by loading the P1DEL register. Configure and start TMR2: a) Clear the TMR2 interrupt flag bit by clearing the TMR2IF bit in the PIR1 register. b) Set the TMR2 prescale value by loading the T2CKPS<1:0> bits in the T2CON register. c) Enable Timer2 by setting the TMR2ON bit in the T2CON register. Enable PWM outputs after a new cycle has started: a) Wait until TMR2 overflows (TMR2IF bit becomes a '1'). The new PWM cycle begins here. b) Enable the CCP1/P1A, P1B, P1C and/or P1D pin outputs by clearing the respective TRISB bits. REGISTERS ASSOCIATED WITH PWM Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Value on POR, BOR Value on all other resets GIE PEIE T0IE INTE RBIE T0IF INTF RBIF 0000 000x 0000 000u 0Ch PIR1 -- ADIF -- -- SSPIF CCP1IF TMR2IF TMR1IF -0-- 0000 -0-- 0000 8Ch PIE1 -- ADIE -- -- SSPIE CCP1IE TMR2IE TMR1IE -0-- 0000 -0-- 0000 86h, 186h TRISB PORTB Data Direction Register 1111 1111 1111 1111 11h TMR2 Timer2 register 0000 0000 0000 0000 92h PR2 Timer2 period register 1111 1111 1111 1111 12h T2CON -000 0000 -000 0000 15h CCPR1L Capture/Compare/PWM register1 (LSB) 17h CCP1CON PWM1M1 97h P1DEL PWM1 Delay value Legend: Legend: DS41120A-page 66 -- TOUTPS3 PWM1M0 TOUTPS2 DC1B1 TOUTPS1 DC1B0 TOUTPS0 CCP1M3 TMR2ON CCP1M2 T2CKPS1 CCP1M1 T2CKPS0 CCP1M0 xxxx xxxx uuuu uuuu 0000 0000 0000 0000 0000 0000 0000 0000 x = unknown, u = unchanged, - = unimplemented read as '0'. Shaded cells are not used by Capture and Timer1. Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 9.0 MASTER SYNCHRONOUS SERIAL PORT (MSSP) MODULE 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, etc. The MSSP module can operate in one of two modes: * Serial Peripheral Interface (SPITM) * Inter-Integrated Circuit (I 2CTM) 1999 Microchip Technology Inc. Advanced Information DS41120A-page 67 PIC16C717/770/771 REGISTER 9-1: SYNC SERIAL PORT STATUS REGISTER (SSPSTAT: 94h) R/W-0 R/W-0 R-0 R-0 R-0 R-0 R-0 R-0 SMP CKE D/A P S R/W UA BF bit7 bit0 R = Readable bit W = Writable bit U = Unimplemented bit, read as `0' - n = Value at POR reset bit 7: SMP: Sample bit SPI Master Mode 1 = Input data sampled at end of data output time 0 = Input data sampled at middle of data output time SPI Slave Mode SMP must be cleared when SPI is used in slave mode In I2C master or slave mode: 1= Slew rate control disabled for standard speed mode (100 kHz and 1 MHz) 0= Slew rate control enabled for high speed mode (400 kHz) bit 6: CKE: SPI Clock Edge Select (Figure 9-3, Figure 9-5, and Figure 9-6) CKP = 0 1 = Data transmitted on rising edge of SCK 0 = Data transmitted on falling edge of SCK CKP = 1 1 = Data transmitted on falling edge of SCK 0 = Data transmitted on rising edge of SCK bit 5: D/A: Data/Address bit (I2C mode only) 1 = Indicates that the last byte received or transmitted was data 0 = Indicates that the last byte received or transmitted was address bit 4: P: Stop bit (I2C mode only. This bit is cleared when the MSSP module is disabled, SSPEN is cleared) 1 = Indicates that a stop bit has been detected last (this bit is '0' on RESET) 0 = Stop bit was not detected last bit 3: S: Start bit (I2C mode only. This bit is cleared when the MSSP module is disabled, SSPEN is cleared) 1 = Indicates that a start bit has been detected last (this bit is '0' on RESET) 0 = Start bit was not detected last bit 2: R/W: Read/Write bit information (I2C mode only) 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. In I2C slave mode: 1 = Read 0 = Write In I2C master mode: 1 = Transmit is in progress 0 = Transmit is not in progress. Or'ing this bit with SEN, RSEN, PEN, RCEN, or AKEN will indicate if the MSSP is in IDLE mode bit 1: UA: Update Address (10-bit I2C mode only) 1 = Indicates that the user needs to update the address in the SSPADD register 0 = Address does not need to be updated bit 0: BF: Buffer Full Status bit Receive (SPI and I2C modes) 1 = Receive complete, SSPBUF is full 0 = Receive not complete, SSPBUF is empty Transmit (I2C mode only) 1 = Data Transmit in progress (does not include the ACK and stop bits), SSPBUF is full 0 = Data Transmit complete (does not include the ACK and stop bits), SSPBUF is empty DS41120A-page 68 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 REGISTER 9-2: SYNC SERIAL PORT CONTROL REGISTER (SSPCON: 14h) 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 SSPEN CKP SSPM3 SSPM2 SSPM1 SSPM0 bit7 bit0 R = Readable bit W = Writable bit - n = Value at POR reset bit 7: WCOL: Write Collision Detect bit Master Mode: 1 = A write to the SSPBUF register was attempted while the I2C conditions were not valid for a transmission to be started 0 = No collision Slave Mode: 1 = The SSPBUF 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 In SPI mode 1 = A new byte is received while the SSPBUF register is still holding the previous data. In case of overflow, the data in SSPSR is lost. Overflow can only occur in slave mode. In slave mode, the user must read the SSPBUF, even if only transmitting data, to avoid setting overflow. In master mode, the overflow bit is not set since each new reception (and transmission) is initiated by writing to the SSPBUF register. (Must be cleared in software). 0 = No overflow In I2C mode 1 = A byte is received while the SSPBUF register is still holding the previous byte. SSPOV is a "don't care" in transmit mode. (Must be cleared in software). 0 = No overflow bit 5: SSPEN: Synchronous Serial Port Enable bit In both modes, when enabled, these pins must be properly configured as input or output. In SPI mode 1 = Enables serial port and configures SCK, SDO, SDI, and SS as the source of the serial port pins 0 = Disables serial port and configures these pins as I/O port pins In I2C mode 1 = Enables the serial port and configures the SDA and SCL pins as the source of the serial port pins 0 = Disables serial port and configures these pins as I/O port pins bit 4: CKP: Clock Polarity Select bit In SPI mode 1 = Idle state for clock is a high level 0 = Idle state for clock is a low level In I2C slave mode SCK release control 1 = Enable clock 0 = Holds clock low (clock stretch) (Used to ensure data setup time) In I2C master mode Unused in this mode bit 3-0: SSPM<3:0>: Synchronous Serial Port Mode Select bits 0000 = SPI master mode, clock = FOSC/4 0001 = SPI master mode, clock = FOSC/16 0010 = SPI master mode, clock = FOSC/64 0011 = SPI master mode, clock = TMR2 output/2 0100 = SPI slave mode, clock = SCK pin. SS pin control enabled. 0101 = SPI slave mode, clock = SCK pin. SS pin control disabled. SS can be used as I/O pin 0110 = I2C slave mode, 7-bit address 0111 = I2C slave mode, 10-bit address 1000 = I2C master mode, clock = FOSC / (4 * (SSPADD+1) ) 1xx1 = Reserved 1x1x = Reserved 1999 Microchip Technology Inc. Advanced Information DS41120A-page 69 PIC16C717/770/771 REGISTER 9-3: SYNC SERIAL PORT CONTROL REGISTER2 (SSPCON2: 91h) 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 ACKEN RCEN PEN RSEN SEN bit7 bit0 R = Readable bit W = Writable bit U = Unimplemented bit, Read as `0' - n = Value at POR reset bit 7: GCEN: General Call Enable bit (In I2C slave mode only) 1 = Enable interrupt when a general call address (0000h) is received in the SSPSR. 0 = General call address disabled. bit 6: ACKSTAT: Acknowledge Status bit (In I2C master mode only) In master transmit mode: 1 = Acknowledge was not received from slave 0 = Acknowledge was received from slave bit 5: ACKDT: Acknowledge Data bit (In I2C master mode only) In master receive mode: Value that will be transmitted when the user initiates an Acknowledge sequence at the end of a receive. 1 = Not Acknowledge 0 = Acknowledge bit 4: ACKEN: Acknowledge Sequence Enable bit (In I2C master mode only). In master receive mode: 1 = Initiate Acknowledge sequence on SDA and SCL pins, and transmit ACKDT data bit. Automatically cleared by hardware. 0 = Acknowledge sequence idle bit 3: RCEN: Receive Enable bit (In I2C master mode only). 1 = Enables Receive mode for I2C 0 = Receive idle bit 2: PEN: Stop Condition Enable bit (In I2C master mode only). SCK release control 1 = Initiate Stop condition on SDA and SCL pins. Automatically cleared by hardware. 0 = Stop condition idle bit 1: RSEN: Repeated Start Condition Enabled bit (In I2C master mode only) 1 = Initiate Repeated Start condition on SDA and SCL pins. Automatically cleared by hardware. 0 = Repeated Start condition idle. bit 0: SEN: Start Condition Enabled bit (In I2C master mode only) 1 = Initiate Start condition on SDA and SCL pins. Automatically cleared by hardware. 0 = Start condition idle. Note: For bits ACKEN, RCEN, PEN, RSEN, SEN: If the I2C module is not in the idle mode, this bit may not be set (no spooling) and the SSPBUF may not be written (or writes to the SSPBUF are disabled). DS41120A-page 70 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 9.1 SPI Mode FIGURE 9-1: 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: MSSP BLOCK DIAGRAM (SPI MODE) Internal Data Bus Read * Serial Data Out (SDO) * Serial Data In (SDI) * Serial Clock (SCK) Write SSPBUF reg Additionally, a fourth pin may be used when in a slave mode of operation: * Slave Select (SS) 9.1.1 SSPSR reg SDI OPERATION Shift Clock bit0 SDO When initializing the SPI, several options need to be specified. This is done by programming the appropriate control bits (SSPCON<5:0> and SSPSTAT<7:6>). These control bits allow the following to be specified: * * * * Master Mode (SCK is the clock output) Slave Mode (SCK is the clock input) Clock Polarity (Idle state of SCK) Data input sample phase (middle or end of data output time) * Clock edge (output data on rising/falling edge of SCK) * Clock Rate (Master mode only) * Slave Select Mode (Slave mode only) Figure 9-1 shows the block diagram of the MSSP module when in SPI mode. SS Control Enable SS Edge Select 2 Clock Select SCK SSPM<3:0> SMP:CKE 4 TMR2 Output 2 2 Edge Select Prescaler Tosc 4, 16, 64 Data to TX/RX in SSPSR Data direction bit The MSSP consists of a transmit/receive Shift Register (SSPSR) and a Buffer Register (SSPBUF). The SSPSR shifts the data in and out of the device, MSb first. The SSPBUF holds the data that was written to the SSPSR, until the received data is ready. Once the 8 bits of data have been received, that byte is moved to the SSPBUF register. Then the buffer full detect bit, BF (SSPSTAT<0>), and the interrupt flag bit, SSPIF (PIR1<3>), are set. This double buffering of the received data (SSPBUF) allows the next byte to start reception before reading the data that was just received. Any write to the SSPBUF register during transmission/reception of data will be ignored, and the write collision detect bit WCOL (SSPCON<7>) will be set. User software must clear the WCOL bit so that it can be determined if the following write(s) to the SSPBUF register completed successfully. When the application software is expecting to receive valid data, the SSPBUF should be read before the next byte of data to transfer is written to the SSPBUF. Buffer full bit, BF (SSPSTAT<0>), indicates when the SSPBUF has been loaded with the received data (transmission is complete). When the SSPBUF is read, bit BF is cleared. This data may be irrelevant if the SPI is only a transmitter. Generally the MSSP Interrupt is used to 1999 Microchip Technology Inc. Advanced Information DS41120A-page 71 PIC16C717/770/771 determine when the transmission/reception has completed. The SSPBUF must be read and/or written. 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 9-1 shows the loading of the SSPBUF (SSPSR) for data transmission. EXAMPLE 9-1: LOADING THE SSPBUF (SSPSR) REGISTER BSF STATUS, RP0 LOOP BTFSS SSPSTAT, BF GOTO BCF MOVF LOOP STATUS, RP0 SSPBUF, W MOVWF RXDATA MOVF TXDATA, W MOVWF SSPBUF ;Specify Bank 1 ;Has data been ;received ;(transmit ;complete)? ;No ;Specify Bank 0 ;W reg = contents ;of SSPBUF ;Save in user RAM ;W reg = contents ; of TXDATA ;New data to xmit SDI is automatically controlled by the SPI module SDO must have TRISB<5> cleared SCK (Master mode) must have TRISB<2> cleared SCK (Slave mode) must have TRISB<2> set SS must have TRISB<1> set, and ANSEL<5> cleared 9.1.3 ENABLING SPI I/O To enable the serial port, MSSP Enable bit, SSPEN (SSPCON<5>) must be set. To reset or reconfigure SPI mode, clear bit SSPEN, re-initialize the SSPCON registers, and then set bit SSPEN. This configures the FIGURE 9-2: * * * * * Any serial port function that is not desired may be overridden by programming the corresponding data direction (TRIS) register to the opposite value. The SSPSR is not directly readable or writable, and can only be accessed by addressing the SSPBUF register. Additionally, the MSSP status register (SSPSTAT) indicates the various status conditions. 9.1.2 SDI, SDO, SCK and SS 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. That is: TYPICAL CONNECTION Figure 9-2 shows a typical connection between two microcontrollers. The master controller (Processor 1) initiates the data transfer by sending the SCK 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 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 SDO SDI Serial Input Buffer (SSPBUF) SDI Shift Register (SSPSR) MSb Serial Input Buffer (SSPBUF) SDO LSb MSb SCK Serial Clock LSb SCK PROCESSOR 1 DS41120A-page 72 Shift Register (SSPSR) PROCESSOR 2 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 9.1.4 MASTER MODE Figure 9-3, Figure 9-5 and Figure 9-6, where the MSb is transmitted first. In master mode, the SPI clock rate (bit rate) is user programmable to be one of the following: The master can initiate the data transfer at any time because it controls the SCK. The master determines when the slave (Processor 2, Figure 9-2) is to broadcast data by the software protocol. * * * * In master mode, the data is transmitted/received as soon as the SSPBUF register is written to. If the SPI module is only going to receive, the SDO output could be disabled (programmed as an input). The SSPSR register will continue to shift in the signal present on the SDI pin at the programmed clock rate. As each byte is received, it will be loaded into the SSPBUF 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". This allows a maximum bit clock frequency (at 20 MHz) of 8.25 MHz. Figure 9-3 shows the waveforms for Master mode. When CKE = 1, the SDO data is valid before there is a clock edge on SCK. The change of the input sample is shown based on the state of the SMP bit. The time when the SSPBUF is loaded with the received data is shown. The clock polarity is selected by appropriately programming bit CKP (SSPCON<4>). This then would give waveforms for SPI communication as shown in FIGURE 9-3: FOSC/4 (or TCY) FOSC/16 (or 4 * TCY) FOSC/64 (or 16 * TCY) Timer2 output/2 SPI MODE WAVEFORM (MASTER MODE) Write to SSPBUF SCK (CKP = 0 CKE = 0) SCK (CKP = 1 CKE = 0) 4 clock modes SCK (CKP = 0 CKE = 1) SCK (CKP = 1 CKE = 1) SDO (CKE = 0) bit7 bit6 bit5 bit4 bit3 bit2 bit1 bit0 SDO (CKE = 1) bit7 bit6 bit5 bit4 bit3 bit2 bit1 bit0 SDI (SMP = 0) bit0 bit7 Input Sample (SMP = 0) SDI (SMP = 1) bit0 bit7 Input Sample (SMP = 1) SSPIF Next Q4 cycle after Q2 SSPSR to SSPBUF 1999 Microchip Technology Inc. Advanced Information DS41120A-page 73 PIC16C717/770/771 9.1.5 SLAVE MODE In slave mode, the data is transmitted and received as the external clock pulses appear on SCK. When the last bit is latched the interrupt flag bit SSPIF (PIR1<3>) is set. While in slave mode, the external clock is supplied by the external clock source on the SCK 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 will wake-up from sleep. 9.1.6 SLAVE SELECT SYNCHRONIZATION The SS pin allows a synchronous slave mode. The SPI must be in slave mode with SS pin control enabled (SSPCON<3:0> = 0100). The pin must not be driven low for the SS pin to function as an input. TRISB<1> must be set. When the SS pin is low, transmission and reception are enabled and the SDO pin is driven. When the SS pin goes high, the FIGURE 9-4: SDO pin is no longer driven, even if in the middle of a 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 module is in Slave Mode with SS pin control enabled, (SSPCON<3:0> = 0100) the SPI module will reset if the SS pin is set to VDD. 2: If the SPI is used in Slave Mode with CKE = '1', then SS 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 SS pin to a high level or clearing the SSPEN bit. To emulate two-wire communication, the SDO pin can be connected to the SDI pin. When the SPI needs to operate as a receiver, the SDO pin can be configured as an input. This disables transmissions from the SDO. The SDI can always be left as an input (SDI function) since it cannot create a bus conflict. SLAVE SYNCHRONIZATION WAVEFORM SS SCK (CKP = 0 CKE = 0) SCK (CKP = 1 CKE = 0) Write to SSPBUF SDO SDI (SMP = 0) bit7 bit6 bit7 bit0 bit0 bit7 bit7 Input Sample (SMP = 0) SSPIF Interrupt Flag Next Q4 cycle after Q2O SSPSR to SSPBUF DS41120A-page 74 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 FIGURE 9-5: SPI SLAVE MODE WAVEFORM (CKE = 0) SS optional SCK (CKP = 0 CKE = 0) SCK (CKP = 1 CKE = 0) Write to SSPBUF SDO bit7 SDI (SMP = 0) bit6 bit5 bit4 bit3 bit2 bit1 bit0 bit0 bit7 Input Sample (SMP = 0) SSPIF Interrupt Flag Next Q4 cycle after Q2O SSPSR to SSPBUF FIGURE 9-6: SPI SLAVE MODE WAVEFORM (CKE = 1) SS not optional SCK (CKP = 0 CKE = 1) SCK (CKP = 1 CKE = 1) Write to SSPBUF SDO SDI (SMP = 0) bit7 bit6 bit5 bit4 bit3 bit2 bit1 bit0 bit0 bit7 Input Sample (SMP = 0) SSPIF Interrupt Flag Next Q4 cycle after Q2O SSPSR to SSPBUF 1999 Microchip Technology Inc. Advanced Information DS41120A-page 75 PIC16C717/770/771 9.1.7 SLEEP OPERATION 9.1.8 In master mode, all module clocks are halted and the transmission/reception will remain in that state until the device wakes from sleep. After the device returns to normal mode, the module will continue to transmit/ receive data. EFFECTS OF A RESET A reset disables the MSSP module and terminates the current transfer. In slave mode, the SPI transmit/receive shift register operates asynchronously to the device. This allows the device to be placed in sleep 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 from sleep. TABLE 9-1: REGISTERS ASSOCIATED WITH SPI OPERATION Address Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 POR, BOR MCLR, WDT 0Bh, 8Bh, 10Bh,18Bh INTCON GIE PEIE T0IE INTE RBIE T0IF INTF RBIF 0000 000x 0000 000u 0Ch PIR1 -- ADIF -- -- SSPIF CCP1IF TMR2IF TMR1IF -0-- 0000 -0-- 0000 8Ch PIE1 -- ADIE -- -- SSPIE CCP1IE TMR2IE TMR1IE -0-- 0000 -0-- 0000 13h SSPBUF xxxx xxxx uuuu uuuu 14h SSPCON WCOL SSPOV Synchronous Serial Port Receive Buffer/Transmit Register SSPEN CKP SSPM3 SSPM2 SSPM1 SSPM0 0000 0000 0000 0000 94h SSPSTAT SMP CKE D/A P S R/W UA BF 0000 0000 0000 0000 Legend: x = unknown, u = unchanged, - = unimplemented read as '0'. Shaded cells are not used by the MSSP in SPI mode. DS41120A-page 76 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 MSSP I 2C Operation 9.2 FIGURE 9-8: I2C MASTER MODE BLOCK DIAGRAM 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. Baud Rate Generator Refer to Application Note AN578, "Use of the SSP Module in the I 2C Multi-Master Environment." SCL Internal Data Bus Read SSPADD<6:0> 7 A "glitch" filter is on the SCL and SDA pins when the pin is an input. This filter operates in both the 100 kHz and 400 kHz modes. In the 100 kHz mode, when these pins are an output, there is a slew rate control of the pin that is independent of device frequency. FIGURE 9-7: SSPBUF reg Shift Clock SSPSR reg SDA MSb LSb I2C SLAVE MODE BLOCK DIAGRAM Match detect Internal Data Bus SSPADD reg Read Write Shift Clock LSb Match detect Addr Match SSPADD reg Start and Stop bit detect Set/Clear S bit and Clear/Set P bit (SSPSTAT reg) and Set SSPIF Two pins are used for data transfer. These are the SCL pin, which is the clock, and the SDA pin, which is the data. The MSSP module functions are enabled by setting SSP Enable bit SSPEN (SSPCON<5>). SSPSR reg MSb Addr Match Start and Stop bit detect / generate SSPBUF reg SCL SDA Write Set, Reset S, P bits (SSPSTAT reg) The MSSP module has six registers for I2C operation. They are the: * * * * * SSP Control Register (SSPCON) SSP Control Register2 (SSPCON2) SSP Status Register (SSPSTAT) Serial Receive/Transmit Buffer (SSPBUF) SSP Shift Register (SSPSR) - Not directly accessible * SSP Address Register (SSPADD) The SSPCON register allows control of the I 2C operation. Four mode selection bits (SSPCON<3:0>) allow one of the following I 2C modes to be selected: * I 2C Slave mode (7-bit address) * I 2C Slave mode (10-bit address) * I 2C Master mode, clock = OSC/4 (SSPADD +1) Before selecting any I 2C mode, the SCL and SDA pins must be programmed to inputs by setting the appropriate TRIS bits. Selecting an I 2C mode, by setting the SSPEN bit, enables the SCL and SDA pins to be used as the clock and data lines in I 2C mode. The SSPSTAT register gives the status of the data transfer. This information includes detection of a START (S) or STOP (P) bit, specifies if the received byte was data or address if the next byte is the completion of 10-bit address, and if this will be a read or write data transfer. 1999 Microchip Technology Inc. Advanced Information DS41120A-page 77 PIC16C717/770/771 SSPBUF is the register to which the transfer data is written to or read from. The SSPSR register shifts the data in or out of the device. In receive operations, the SSPBUF and SSPSR create a doubled buffered receiver. This allows reception of the next byte to begin before reading the last byte of received data. When the complete byte is received, it is transferred to the SSPBUF register and flag bit SSPIF is set. If another complete byte is received before the SSPBUF register is read, a receiver overflow has occurred and bit SSPOV (SSPCON<6>) is set and the byte in the SSPSR is lost. The SSPADD register holds the slave address. In 10-bit mode, the user needs to write the high byte of the address (1111 0 A9 A8 0). Following the high byte address match, the low byte of the address needs to be loaded (A7:A0). 9.2.1 SLAVE MODE In slave mode, the SCL and SDA pins must be configured as inputs. The MSSP module will override the input state with the output data when required (slavetransmitter). 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 then load the SSPBUF register with the received value currently in the SSPSR register. There are certain conditions that will cause the MSSP module not to give this ACK pulse. These are if either (or both): a) b) The buffer full bit BF (SSPSTAT<0>) was set before the transfer was received. The overflow bit SSPOV (SSPCON<6>) was set before the transfer was received. If the BF bit is set, the SSPSR register value is not loaded into the SSPBUF, but bit SSPIF and SSPOV are set. Table 9-2 shows what happens when a data transfer byte is received, given the status of bits BF and SSPOV. The shaded cells show the condition where user software did not properly clear the overflow condition. Flag bit BF is cleared by reading the SSPBUF register while bit SSPOV is cleared through software. The SCL clock input must have a minimum high and low time for proper operation. The high and low times of the I2C specification as well as the requirement of the MSSP module is shown in timing parameter #100 and parameter #101 of the Electrical Specifications. 9.2.1.1 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 SSPSR register. All incoming bits are sampled with the rising edge of the clock (SCL) line. The value of register SSPSR<7:1> is compared to the value of the SSPADD register. The address is compared on the falling edge of the eighth clock (SCL) pulse. If the addresses match, and the BF and SSPOV bits are clear, the following events occur: a) b) c) d) The SSPSR register value is loaded into the SSPBUF register on the falling edge of the 8th SCL pulse. The buffer full bit, BF is set on the falling edge of the 8th SCL pulse. An ACK pulse is generated. SSP interrupt flag bit, SSPIF (PIR1<3>) is set (interrupt is generated if enabled) - on the falling edge of the 9th SCL pulse. In 10-bit address 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. Bit R/W (SSPSTAT<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 `1111 0 A9 A8 0', where A9 and A8 are the two MSbs of the address. The sequence of events for a 10-bit address is as follows, with steps 7- 9 for slave-transmitter: 1. 2. 3. 4. 5. 6. 7. 8. 9. Receive first (high) byte of Address (bits SSPIF, BF, and bit UA (SSPSTAT<1>) are set). Update the SSPADD register with second (low) byte of Address (clears bit UA and releases the SCL line). Read the SSPBUF register (clears bit BF) and clear flag bit SSPIF. Receive second (low) byte of Address (bits SSPIF, BF, and UA are set). Update the SSPADD register with the first (high) byte of Address. This will clear bit UA and release the SCL line. Read the SSPBUF register (clears bit BF) and clear flag bit SSPIF. Receive Repeated Start condition. Receive first (high) byte of Address (bits SSPIF and BF are set). Read the SSPBUF register (clears bit BF) and clear flag bit SSPIF. Note: DS41120A-page 78 ADDRESSING Following the Repeated Start condition (step 7) in 10-bit mode, the user only needs to match the first 7-bit address. The user does not update the SSPADD for the second half of the address. Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 9.2.1.2 SLAVE RECEPTION When the R/W bit of the address byte is clear and an address match occurs, the R/W bit of the SSPSTAT register is cleared. The received address is loaded into the SSPBUF register. A MSSP interrupt is generated for each data transfer byte. Flag bit SSPIF (PIR1<3>) must be cleared in software. The SSPSTAT register is used to determine the status of the received byte. Note: When the address byte overflow condition exists, then no acknowledge (ACK) pulse is given. An overflow condition is defined as either bit BF (SSPSTAT<0>) or bit SSPOV (SSPCON<6>) and is set. TABLE 9-2: The SSPBUF will be loaded if the SSPOV bit is set and the BF flag is cleared. If a read of the SSPBUF was performed, but the user did not clear the state of the SSPOV bit before the next receive occurred, the ACK is not sent and the SSPBUF is updated. DATA TRANSFER RECEIVED BYTE ACTIONS Status Bits as Data Transfer is Received BF SSPOV SSPSR SSPBUF Generate ACK Pulse 0 1 1 0 0 0 1 1 Yes No No Yes Yes No No No Note 1: 9.2.1.3 Set bit SSPIF (SSP Interrupt occurs if enabled) Yes Yes Yes Yes Shaded cells show the conditions where the user software did not properly clear the overflow condition. SLAVE TRANSMISSION When the R/W bit of the incoming address byte is set and an address match occurs, the R/W bit of the SSPSTAT register is set. The received address is loaded into the SSPBUF register. The ACK pulse will be sent on the ninth bit, and the SCL pin is held low. The transmit data must be loaded into the SSPBUF register, which also loads the SSPSR register. Then the SCL pin should be enabled by setting bit CKP (SSPCON<4>). The master must monitor the SCL pin prior to asserting another clock pulse. The slave devices may be holding off the master by stretching the clock. The eight data bits are shifted out on the falling edge of the SCL input. This ensures that the SDA signal is valid during the SCL high time (Figure 9-10). 1999 Microchip Technology Inc. A MSSP interrupt is generated for each data transfer byte. The SSPIF flag bit must be cleared in software, and the SSPSTAT register is used to determine the status of the byte transfer. The SSPIF flag bit is set on the falling edge of the ninth clock pulse. As a slave-transmitter, the ACK pulse from the masterreceiver is latched on the rising edge of the ninth SCL input pulse. If the SDA line was high (not ACK), then the data transfer is complete. When the not ACK is latched by the slave, the slave logic is reset and the slave then monitors for another occurrence of the START bit. If the SDA line was low (ACK), the transmit data must be loaded into the SSPBUF register, which also loads the SSPSR register. Then the SCL pin should be enabled by setting the CKP bit. Advanced Information DS41120A-page 79 PIC16C717/770/771 I 2C WAVEFORMS FOR RECEPTION (7-BIT ADDRESS) FIGURE 9-9: R/W=0 ACK Receiving Address A7 A6 A5 A4 A3 A2 A1 SDA SCL 1 S 2 3 4 5 6 7 Receiving Data ACK D7 D6 D5 D4 D3 D2 D1 D0 1 9 8 2 3 4 5 6 7 8 9 Not Receiving Data ACK D7 D6 D5 D4 D3 D2 D1 D0 1 2 3 4 5 8 7 6 9 SSPIF P Bus Master terminates transfer BF (SSPSTAT<0>) Cleared in software SSPBUF register is read SSPOV (SSPCON<6>) Bit SSPOV is set because the SSPBUF register is still full. ACK is not sent. FIGURE 9-10: I 2C WAVEFORMS FOR TRANSMISSION (7-BIT ADDRESS) R/W = 1 ACK Receiving Address SDA SCL A7 S A6 1 2 Data in sampled A5 A4 A3 A2 A1 3 4 5 6 7 D7 8 9 R/W = 0 Not ACK Transmitting Data 1 SCL held low while CPU responds to SSPIF D6 D5 D4 D3 D2 D1 D0 2 3 4 5 6 7 8 9 P SSPIF BF (SSPSTAT<0>) cleared in software SSPBUF is written in software From SSP interrupt service routine CKP (SSPCON<4>) Set bit after writing to SSPBUF (the SSPBUF must be written-to before the CKP bit can be set) DS41120A-page 80 Advanced Information 1999 Microchip Technology Inc. 1999 Microchip Technology Inc. S 1 2 1 UA (SSPSTAT<1>) 4 1 5 0 6 7 A9 A8 8 UA is set indicating that the SSPADD needs to be updated SSPBUF is written with contents of SSPSR 3 1 9 ACK Receive First Byte of AddressR/W = 0 1 BF (SSPSTAT<0>) (PIR1<3>) SSPIF SCL SDA 1 3 4 5 Cleared in software 2 Advanced Information 7 UA is set indicating that SSPADD needs to be updated Cleared by hardware when SSPADD is updated. 6 8 A6 A5 A4 A3 A2 A1 A0 Receive Second Byte of Address Dummy read of SSPBUF to clear BF flag A7 Clock is held low until update of SSPADD has taken place 9 ACK 2 3 1 4 1 5 0 Cleared in software 1 1 Cleared by hardware when SSPADD is updated. Dummy read of SSPBUF to clear BF flag Sr 1 6 7 A9 A8 8 9 Receive First Byte of Address R/W=1 ACK 3 4 5 6 7 8 9 ACK P Cleared in software Bus Master terminates transfer CKP has to be set for clock to be released 2 Write of SSPBUF initiates transmit 1 D7 D6 D5 D4 D3 D2 D1 D0 Transmitting Data Byte Master sends NACK Transmit is complete PIC16C717/770/771 FIGURE 9-11: I2C SLAVE-TRANSMITTER (10-BIT ADDRESS) DS41120A-page 81 DS41120A-page 82 S 1 1 UA (SSPSTAT<1>) BF (SSPSTAT<0>) (PIR1<3>) SSPIF SCL SDA 2 1 3 1 5 0 6 A9 7 A8 8 UA is set indicating that the SSPADD needs to be updated 9 ACK R/W = 0 SSPBUF is written with contents of SSPSR 4 1 Receive First Byte of Address 1 3 A5 4 A4 Advanced Information 7 A1 8 A0 UA is set indicating that SSPADD needs to be updated 6 A2 Cleared by hardware when SSPADD is updated with low byte of address. 5 A3 Cleared in software 2 A6 Dummy read of SSPBUF to clear BF flag A7 Receive Second Byte of Address Clock is held low until update of SSPADD has taken place 9 ACK 3 D5 4 D4 5 D3 Cleared in software 2 D6 Cleared by hardware when SSPADD is updated with high byte of address. Dummy read of SSPBUF to clear BF flag 1 D7 6 D2 Receive Data Byte 7 D1 8 D0 9 ACK R/W = 1 Read of SSPBUF clears BF flag P Bus Master terminates transfer PIC16C717/770/771 FIGURE 9-12: I2C SLAVE-RECEIVER (10-BIT ADDRESS) 1999 Microchip Technology Inc. PIC16C717/770/771 9.2.2 GENERAL CALL ADDRESS SUPPORT If the general call address matches, the SSPSR is transferred to the SSPBUF, the BF flag is set (eighth bit), and on the falling edge of the ninth bit (ACK bit), the SSPIF flag 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 SSPBUF to determine if the address was device specific or a general call address. In 10-bit mode, the SSPADD is required to be updated for the second half of the address to match, and the UA bit is set (SSPSTAT<1>). If the general call address is sampled when GCEN is set while the slave is configured in 10-bit address 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 9-13). 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 (SSPCON2<7> is set). Following a start-bit detect, 8 bits are shifted into SSPSR and the address is compared against SSPADD. It is also compared to the general call address, fixed in hardware. FIGURE 9-13: SLAVE MODE GENERAL CALL ADDRESS SEQUENCE (7 OR 10-BIT MODE) Address is compared to General Call Address after ACK, set interrupt flag R/W = 0 ACK D7 General Call Address SDA Receiving data ACK D6 D5 D4 D3 D2 D1 D0 2 3 4 5 6 7 8 SCL S 1 2 3 4 5 6 7 8 9 1 9 SSPIF BF (SSPSTAT<0>) Cleared in software SSPBUF is read SSPOV (SSPCON<6>) '0' GCEN (SSPCON2<7>) '1' 1999 Microchip Technology Inc. Advanced Information DS41120A-page 83 PIC16C717/770/771 9.2.3 SLEEP OPERATION 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. While in sleep mode, the I2C module can receive addresses or data, and when an address match or complete byte transfer occurs, wake the processor from sleep (if the SSP interrupt bit is enabled). 9.2.4 In master mode, the SCL and SDA lines are manipulated by the MSSP hardware. The following events will cause SSP Interrupt Flag bit, SSPIF, to be set (SSP Interrupt if enabled): EFFECTS OF A RESET * * * * * A reset disables the MSSP module and terminates the current transfer. 9.2.5 MASTER MODE Master mode operation is supported by interrupt generation on the detection of the START and STOP conditions. The STOP (P) and START (S) bits are cleared START condition STOP condition Data transfer byte transmitted/received Acknowledge transmit Repeated Start FIGURE 9-14: MSSP BLOCK DIAGRAM (I2C MASTER MODE) SSPM<3:0>, SSPADD<6:0> Internal Data Bus Read Write SSPBUF Shift Clock SDA SDA in SSPSR SCL in Bus Collision DS41120A-page 84 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 clock cntl SCL Receive Enable MSb clock arbitrate/WCOL detect (hold off clock source) Baud Rate Generator Set/Reset, S, P, WCOL (SSPSTAT) Set SSPIF, BCLIF Reset ACKSTAT, PEN (SSPCON2) Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 9.2.6 MULTI-MASTER OPERATION 9.2.7.1 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 bit P (SSPSTAT<4>) is set, or the bus is idle with both the S and P bits clear. When the bus is busy, enabling the SSP Interrupt will generate the interrupt when the STOP condition occurs. In multi-master operation, the SDA 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 BCLIF bit. The states where arbitration can be lost are: * * * * * Address Transfer Data Transfer A Start Condition A Repeated Start Condition An Acknowledge Condition 9.2.7 I2C MASTER OPERATION SUPPORT Master Mode is enabled by setting and clearing the appropriate SSPM bits in SSPCON and by setting the SSPEN bit. Once master mode is enabled, the user has six options. - Assert a start condition on SDA and SCL. - Assert a Repeated Start condition on SDA and SCL. - Write to the SSPBUF register initiating transmission of data/address. - Generate a stop condition on SDA and SCL. - Configure the I2C port to receive data. - Generate an Acknowledge condition at the end of a received byte of data. I2C MASTER MODE OPERATION 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 SDA, while SCL 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 receive bit. Serial data is received via SDA while SCL 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 SPI mode operation is now used to set the SCL clock frequency for either 100 kHz, 400 kHz, or 1 MHz I2C operation. The baud rate generator reload value is contained in the lower 7 bits of the SSPADD register. The baud rate generator will automatically begin counting on a write to the SSPBUF. 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 SCL pin will remain in its last state A typical transmit sequence would go as follows: Note: The MSSP 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 SSPBUF register to initiate transmission before the START condition is complete. In this case, the SSPBUF will not be written to, and the WCOL bit will be set, indicating that a write to the SSPBUF did not occur. a) b) c) d) e) f) g) h) 1999 Microchip Technology Inc. The user generates a Start Condition by setting the START enable bit (SEN) in SSPCON2. SSPIF is set. The module will wait the required start time before any other operation takes place. The user loads the SSPBUF with address to transmit. Address is shifted out the SDA pin until all 8 bits are transmitted. The MSSP Module shifts in the ACK bit from the slave device, and writes its value into the SSPCON2 register ( SSPCON2<6>). The module generates an interrupt at the end of the ninth clock cycle by setting SSPIF. The user loads the SSPBUF with eight bits of data. DATA is shifted out the SDA pin until all 8 bits are transmitted. Advanced Information DS41120A-page 85 PIC16C717/770/771 i) j) k) l) The MSSP Module shifts in the ACK bit from the slave device and writes its value into the SSPCON2 register ( SSPCON2<6>). The MSSP module generates an interrupt at the end of the ninth clock cycle by setting the SSPIF bit. The user generates a STOP condition by setting the STOP enable bit PEN in SSPCON2. Interrupt is generated once the STOP condition is complete. 9.2.8 In I2C master mode, the BRG is reloaded automatically. If Clock Arbitration is taking place for instance, the BRG will be reloaded when the SCL pin is sampled high (Figure 9-16). FIGURE 9-15: BAUD RATE GENERATOR BLOCK DIAGRAM SSPM<3:0> BAUD RATE GENERATOR SSPADD<6:0> SSPM<3:0> Reload SCL Control In I2C master mode, the reload value for the BRG is located in the lower 7 bits of the SSPADD register (Figure 9-15). When the BRG is loaded with this value, 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 clock. CLKOUT Reload BRG Down Counter FOSC/4 FIGURE 9-16: BAUD RATE GENERATOR TIMING WITH CLOCK ARBITRATION SDA DX DX-1 SCL de-asserted but slave holds SCL low (clock arbitration) SCL allowed to transition high SCL BRG decrements (on Q2 and Q4 cycles) BRG value 03h 02h 01h 00h (hold off) 03h 02h SCL is sampled high, reload takes place, and BRG starts its count. BRG reload DS41120A-page 86 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 9.2.9 I2C MASTER MODE START CONDITION TIMING 9.2.9.1 If the user writes the SSPBUF when an START sequence is in progress, then WCOL is set and the contents of the buffer are unchanged (the write doesn't occur). To initiate a START condition, the user sets the start condition enable bit, SEN (SSPCON2<0>). If the SDA and SCL pins are sampled high, the baud rate generator is re-loaded with the contents of SSPADD<6:0>, and starts its count. If SCL and SDA are both sampled high when the baud rate generator times out (TBRG), the SDA pin is driven low. The action of the SDA being driven low while SCL is high is the START condition, and causes the S bit (SSPSTAT<3>) to be set. Following this, the baud rate generator is reloaded with the contents of SSPADD<6:0> and resumes its count. When the baud rate generator times out (TBRG), the SEN bit (SSPCON2<0>) will be automatically cleared by hardware, the baud rate generator is suspended leaving the SDA line held low, and the START condition is complete. Note: WCOL STATUS FLAG Note: Because queueing of events is not allowed, writing to the lower 5 bits of SSPCON2 is disabled until the START condition is complete. If at the beginning of START condition, the SDA and SCL pins are already sampled low, or if during the START condition, the SCL line is sampled low before the SDA line is driven low, a bus collision occurs, the Bus Collision Interrupt Flag (BCLIF) is set, the START condition is aborted, and the I2C module is reset into its IDLE state. FIGURE 9-17: FIRST START BIT TIMING Set S bit (SSPSTAT<3>) Write to SEN bit occurs here. SDA = 1, SCL = 1 TBRG At completion of start bit, Hardware clears SEN bit and sets SSPIF bit TBRG Write to SSPBUF occurs here 1st Bit SDA 2nd Bit TBRG SCL TBRG S 1999 Microchip Technology Inc. Advanced Information DS41120A-page 87 PIC16C717/770/771 FIGURE 9-18: START CONDITION FLOWCHART SSPEN = 1, SSPCON<3:0> = 1000 Idle Mode SEN (SSPCON2<0> = 1) Bus collision detected, Set BCLIF, Release SCL, Clear SEN No SDA = 1? SCL = 1? Yes Load BRG with SSPADD<6:0> No Yes SCL= 0? No No SDA = 0? Yes BRG Rollover? Yes Reset BRG Force SDA = 0, Load BRG with SSPADD<6:0>, Set S bit. No SCL = 0? Yes No BRG rollover? Yes Reset BRG Force SCL = 0, Start Condition Done, Clear SEN and set SSPIF DS41120A-page 88 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 9.2.10 I2C MASTER MODE REPEATED START CONDITION TIMING Immediately following the SSPIF bit getting set, the user may write the SSPBUF 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). A Repeated Start condition occurs when the RSEN bit (SSPCON2<1>) is set high and the I2C module is in the idle state. When the RSEN bit is set, the SCL pin is asserted low. When the SCL pin is sampled low, the baud rate generator is loaded with the contents of SSPADD<6:0>, and begins counting. The SDA pin is released (brought high) for one baud rate generator count (TBRG). When the baud rate generator times out, if SDA is sampled high, the SCL pin will be de-asserted (brought high). When SCL is sampled high the baud rate generator is re-loaded with the contents of SSPADD<6:0> and begins counting. SDA and SCL must be sampled high for one TBRG. This action is then followed by assertion of the SDA pin (SDA is low) for one TBRG while SCL is high. Following this, the RSEN bit in the SSPCON2 register will be automatically cleared, and the baud rate generator is not reloaded, leaving the SDA pin held low. As soon as a start condition is detected on the SDA and SCL pins, the S bit (SSPSTAT<3>) will be set. The SSPIF bit will not be set until the baud rate generator has timed-out. 9.2.10.1 WCOL STATUS FLAG If the user writes the SSPBUF when a Repeated Start sequence is in progress, then WCOL is set and the contents of the buffer are unchanged (the write doesn't occur). Note: Because queueing of events is not allowed, writing of the lower 5 bits of SSPCON2 is disabled until the Repeated Start condition is complete. Note 1: If RSEN is set while any other event is in progress, it will not take effect. Note 2: A bus collision during the Repeated Start condition occurs if: * SDA is sampled low when SCL goes from low to high. * SCL goes low before SDA is asserted low. This may indicate that another master is attempting to transmit a data "1". FIGURE 9-19: REPEAT START CONDITION WAVEFORM Set S (SSPSTAT<3>) Write to SSPCON2 occurs here. SDA = 1, SCL (no change) SDA = 1, SCL = 1 TBRG TBRG At completion of start bit, hardware clear RSEN bit and set SSPIF TBRG 1st Bit SDA Falling edge of ninth clock End of Xmit Write to SSPBUF occurs here. TBRG SCL TBRG Sr = Repeated Start 1999 Microchip Technology Inc. Advanced Information DS41120A-page 89 PIC16C717/770/771 FIGURE 9-20: REPEATED START CONDITION FLOWCHART (PAGE 1) Start Idle Mode, SSPEN = 1, SSPCON<3:0> = 1000 B RSEN = 1 Force SCL = 0 No SCL = 0? Yes Release SDA, Load BRG with SSPADD<6:0> BRG rollover? No Yes Release SCL (Clock Arbitration) SCL = 1? No Yes Bus Collision, Set BCLIF, Release SDA, Clear RSEN No SDA = 1? Yes Load BRG with SSPADD<6:0> C DS41120A-page 90 A Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 FIGURE 9-21: REPEATED START CONDITION FLOWCHART (PAGE 2) B C A Yes No No SCL = 1? SDA = 0? No Yes BRG rollover? Yes Reset BRG Force SDA = 0, Load BRG with SSPADD<6:0> Set S No SCL = '0'? Yes Reset BRG 1999 Microchip Technology Inc. Advanced Information No BRG rollover? Yes Force SCL = 0, Repeated Start condition done, Clear RSEN, Set SSPIF. DS41120A-page 91 PIC16C717/770/771 9.2.11 I2C MASTER MODE TRANSMISSION Transmission of a data byte, a 7-bit address, or either half of a 10-bit address is accomplished by simply writing a value to the SSPBUF register. This action will set the buffer full flag (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 SDA pin after the falling edge of SCL is asserted (see data hold time spec). SCL is held low for one baud rate generator roll over count (TBRG). Data should be valid before SCL is released high (see data setup time spec). When the SCL pin is released high, it is held that way for TBRG, the data on the SDA pin must remain stable for that duration and some hold time after the next falling edge of SCL. After the eighth bit is shifted out (the falling edge of the eighth clock), the BF flag is cleared and the master releases SDA allowing the slave device being addressed to respond with an ACK bit during the ninth bit time, if an address match occurs or if data was received properly. The status of ACK is read into the ACKDT 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 SSPIF is set, and the master clock (baud rate generator) is suspended until the next data byte is loaded into the SSPBUF leaving SCL low and SDA unchanged (Figure 9-23). 9.2.11.3 ACKSTAT STATUS FLAG In transmit mode, the ACKSTAT bit (SSPCON2<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. After the write to the SSPBUF, each bit of address will be shifted out on the falling edge of SCL until all seven address bits and the R/W bit are completed. On the falling edge of the eighth clock, the master will de-assert the SDA pin allowing the slave to respond with an acknowledge. On the falling edge of the ninth clock, the master will sample the SDA pin to see if the address was recognized by a slave. The status of the ACK bit is loaded into the ACKSTAT status bit (SSPCON2<6>). Following the falling edge of the ninth clock transmission of the address, the SSPIF is set, the BF flag is cleared, and the baud rate generator is turned off until another write to the SSPBUF takes place, holding SCL low and allowing SDA to float. 9.2.11.1 BF STATUS FLAG In transmit mode, the BF bit (SSPSTAT<0>) is set when the CPU writes to SSPBUF and is cleared when all 8 bits are shifted out. 9.2.11.2 WCOL STATUS FLAG If the user writes the SSPBUF when a transmit is already in progress (i.e. SSPSR is still shifting out a data byte), then WCOL is set and the contents of the buffer are unchanged (the write doesn't occur). WCOL must be cleared in software. DS41120A-page 92 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 FIGURE 9-22: MASTER TRANSMIT FLOWCHART Idle Mode Write SSPBUF Num_Clocks = 0, BF = 1 Force SCL = 0 Release SDA so slave can drive ACK, Force BF = 0 Yes Num_Clocks = 8? No Load BRG with SSPADD<6:0>, start BRG count Load BRG with SSPADD<6:0>, start BRG count, SDA = Current Data bit BRG rollover? BRG rollover? No No Yes Yes Force SCL = 1, Stop BRG Stop BRG, Force SCL = 1 (Clock Arbitration) SCL = 1? (Clock Arbitration) No SCL = 1? No Yes Yes Read SDA and place into ACKSTAT bit (SSPCON2<6>) No SDA = Data bit? Bus collision detected Set BCLIF, hold prescale off, Clear XMIT enable Yes Load BRG with SSPADD<6:0>, count high time Load BRG with SSPADD<6:0>, count SCL high time Rollover? No Yes BRG rollover? No No SCL = 0? SDA = Data bit? No Yes Yes Yes Force SCL = 0, Set SSPIF Reset BRG Num_Clocks = Num_Clocks + 1 1999 Microchip Technology Inc. Advanced Information DS41120A-page 93 DS41120A-page 94 S Advanced Information R/W PEN SEN BF (SSPSTAT<0>) SSPIF SCL SDA A6 A5 A4 A3 A2 A1 3 4 5 cleared in software 2 6 7 8 9 After start condition SEN cleared by hardware. SSPBUF written 1 D7 3 D5 4 D4 5 D3 6 D2 7 D1 SSPBUF is written in software 8 D0 cleared in software service routine From SSP interrupt 2 D6 Transmitting Data or Second Half of 10-bit Address From slave clear ACKSTAT bit SSPCON2<6> 1 SCL held low while CPU responds to SSPIF ACK = 0 R/W = 0 SSPBUF written with 7 bit address and R/W start transmit A7 Transmit Address to Slave SEN = 0 Write SSPCON2<0> SEN = 1 START condition begins P Cleared in software 9 ACK ACKSTAT in SSPCON2 = 1 PIC16C717/770/771 FIGURE 9-23: I 2C MASTER MODE TIMING (TRANSMISSION, 7 OR 10-BIT ADDRESS) 1999 Microchip Technology Inc. PIC16C717/770/771 9.2.12 I2C MASTER MODE RECEPTION Master mode reception is enabled by setting the receive enable bit, RCEN (SSPCON2<3>). Note: The MSSP Module must be in an IDLE 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 SCL pin changes (high to low/ low to high) and data is shifted into the SSPSR. After the falling edge of the eighth clock, the receive enable flag is automatically cleared, the contents of the SSPSR are loaded into the SSPBUF, the BF flag is set, the SSPIF is set, and the baud rate generator is suspended from counting, holding SCL low. The SSP is now in IDLE state, awaiting the next command. When the buffer is read by the CPU, the BF flag is automatically cleared. The user can then send an acknowledge bit at the end of reception, by setting the acknowledge sequence enable bit, ACKEN (SSPCON2<4>). 9.2.12.1 BF STATUS FLAG In receive operation, BF is set when an address or data byte is loaded into SSPBUF from SSPSR. It is cleared when SSPBUF is read. 9.2.12.2 SSPOV STATUS FLAG In receive operation, SSPOV is set when 8 bits are received into the SSPSR, and the BF flag is already set from a previous reception. 9.2.12.3 WCOL STATUS FLAG If the user writes the SSPBUF when a receive is already in progress (i.e. SSPSR is still shifting in a data byte), then WCOL is set and the contents of the buffer are unchanged (the write doesn't occur). 1999 Microchip Technology Inc. Advanced Information DS41120A-page 95 PIC16C717/770/771 FIGURE 9-24: MASTER RECEIVER FLOWCHART Idle mode RCEN = 1 Num_Clocks = 0, Release SDA Force SCL=0, Load BRG w/ SSPADD<6:0>, start count BRG rollover? No Yes Release SCL (Clock Arbitration) SCL = 1? No Yes Sample SDA, Shift data into SSPSR Load BRG with SSPADD<6:0>, start count. BRG rollover? No Yes SCL = 0? No Yes Num_Clocks = Num_Clocks + 1 No Num_Clocks = 8? Yes Force SCL = 0, Set SSPIF, Set BF. Move contents of SSPSR into SSPBUF, Clear RCEN. DS41120A-page 96 Advanced Information 1999 Microchip Technology Inc. 1999 Microchip Technology Inc. S Advanced Information ACKEN SSPOV BF (SSPSTAT<0>) SDA = 0, SCL = 1 while CPU responds to SSPIF SSPIF SCL SDA 1 A7 2 4 5 6 Cleared in software 3 7 8 9 Transmit Address to Slave R/W = 1 A6 A5 A4 A3 A2 A1 ACK 2 3 5 6 7 8 D0 9 ACK 2 3 4 5 6 7 8 9 ACK is not sent ACK Cleared in software Set SSPIF interrupt at end of acknowledge sequence SSPOV is set because SSPBUF is still full Cleared in software P Bus Master terminates transfer Set P bit (SSPSTAT<4>) and SSPIF Set SSPIF interrupt at end of acknowledge sequence PEN bit = 1 written here Data shifted in on falling edge of CLK Set SSPIF at end of receive 1 D7 D6 D5 D4 D3 D2 D1 D0 RCEN cleared automatically Set ACKEN start acknowledge sequence SDA = ACKDT = 1 Receiving Data from Slave RCEN = 1 start next receive ACK from Master SDA = ACKDT = 0 Last bit is shifted into SSPSR and contents are unloaded into SSPBUF Cleared in software Set SSPIF interrupt at end of receive 4 Cleared in software 1 Receiving Data from Slave D7 D6 D5 D4 D3 D2 D1 Master configured as a receiver by programming SSPCON2<3>, (RCEN = 1) SEN = 0 Write to SSPBUF occurs here RCEN cleared ACK from Slave automatically Start XMIT Write to SSPCON2<0>, (SEN = 1) Begin Start Condition Write to SSPCON2<4> to start acknowledge sequence SDA = ACKDT (SSPCON2<5>) = 0 PIC16C717/770/771 FIGURE 9-25: I 2C MASTER MODE TIMING (RECEPTION 7-BIT ADDRESS) DS41120A-page 97 PIC16C717/770/771 9.2.13 ACKNOWLEDGE SEQUENCE TIMING the baud rate generator counts for TBRG . The SCL 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 IDLE mode. (Figure 9-26) An acknowledge sequence is enabled by setting the acknowledge sequence enable bit, ACKEN (SSPCON2<4>). When this bit is set, the SCL pin is pulled low and the contents of the acknowledge data bit is presented on the SDA 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 SCL pin is de-asserted (pulled high). When the SCL pin is sampled high (clock arbitration), 9.2.13.1 WCOL STATUS FLAG If the user writes the SSPBUF when an acknowledged sequence is in progress, then WCOL is set and the contents of the buffer are unchanged (the write doesn't occur). FIGURE 9-26: ACKNOWLEDGE SEQUENCE WAVEFORM Acknowledge sequence starts here, Write to SSPCON2 ACKEN = 1, ACKDT = 0 ACKEN automatically cleared TBRG TBRG SDA SCL ACK D0 8 9 SSPIF Set SSPIF at the end of receive Cleared in software Cleared in software Set SSPIF at the end of acknowledge sequence Note: TBRG = one baud rate generator period. DS41120A-page 98 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 FIGURE 9-27: ACKNOWLEDGE FLOWCHART Idle mode Set ACKEN Force SCL = 0 BRG rollover? Yes No No SCL = 0? Yes SCL = 0? Yes Drive ACKDT bit (SSPCON2<5>) onto SDA pin, Load BRG with SSPADD<6:0>, start count. Reset BRG Force SCL = 0, Clear ACKEN, Set SSPIF No No ACKDT = 1? Yes No BRG rollover? Yes Yes Force SCL = 1 No SDA = 1? No Bus collision detected, Set BCLIF, Release SCL, Clear ACKEN SCL = 1? (Clock Arbitration) Yes Load BRG with SSPADD <6:0>, start count. 1999 Microchip Technology Inc. Advanced Information DS41120A-page 99 PIC16C717/770/771 9.2.14 STOP CONDITION TIMING while SCL is high, the P bit (SSPSTAT<4>) is set. A TBRG later the PEN bit is cleared and the SSPIF bit is set (Figure 9-28). A stop bit is asserted on the SDA pin at the end of a receive/transmit by setting the Stop Sequence Enable bit PEN (SSPCON2<2>). At the end of a receive/transmit, the SCL line is held low after the falling edge of the ninth clock. When the PEN bit is set, the master will assert the SDA line low . When the SDA line is sampled low, the baud rate generator is reloaded and counts down to 0. When the baud rate generator times out, the SCL pin will be brought high and one TBRG (baud rate generator rollover count) later, the SDA pin will be de-asserted. When the SDA pin is sampled high Whenever the firmware decides to take control of the bus, it will first determine if the bus is busy by checking the S and P bits in the SSPSTAT register. If the bus is busy, then the CPU can be interrupted (notified) when a Stop bit is detected (i.e. bus is free). 9.2.14.1 WCOL STATUS FLAG If the user writes the SSPBUF when a STOP sequence is in progress, then WCOL is set and the contents of the buffer are unchanged (the write doesn't occur). FIGURE 9-28: STOP CONDITION RECEIVE OR TRANSMIT MODE SCL = 1 for TBRG, followed by SDA = 1 for TBRG after SDA sampled high. P bit (SSPSTAT<4>) is set Write to SSPCON2 Set PEN PEN bit (SSPCON2<2>) is cleared by hardware and the SSPIF bit is set Falling edge of 9th clock TBRG SCL SDA ACK P TBRG TBRG TBRG SCL brought high after TBRG SDA asserted low before rising edge of clock to setup stop condition. Note: TBRG = one baud rate generator period. DS41120A-page 100 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 FIGURE 9-29: STOP CONDITION FLOWCHART Idle Mode, SSPEN = 1, SSPCON<3:0> = 1000 PEN = 1 Start BRG Force SDA = 0 SCL doesn't change No BRG rollover? No SDA = 0? Yes Release SDA, Start BRG Yes Start BRG BRG rollover? BRG rollover? No No Yes No P bit Set? Yes De-assert SCL, SCL = 1 (Clock Arbitration) SCL = 1? No Bus Collision detected, Set BCLIF, Clear PEN Yes SDA going from 0 to 1 while SCL = 1 Set SSPIF, Stop Condition done PEN cleared. Yes 1999 Microchip Technology Inc. Advanced Information DS41120A-page 101 PIC16C717/770/771 9.2.15 CLOCK ARBITRATION 9.2.16 Clock arbitration occurs when the master, during any receive, transmit or repeated start/stop condition, deasserts the SCL pin (SCL allowed to float high). When the SCL pin is allowed to float high, the baud rate generator (BRG) is suspended from counting until the SCL pin is actually sampled high. When the SCL pin is sampled high, the baud rate generator is reloaded with the contents of SSPADD<6:0> and begins counting. This ensures that the SCL 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 9-30). SLEEP OPERATION While in sleep mode, the I2C module can receive addresses or data, and when an address match or complete byte transfer occurs, wake the processor from sleep ( if the SSP interrupt is enabled). 9.2.17 EFFECTS OF A RESET A reset disables the MSSP module and terminates the current transfer. FIGURE 9-30: CLOCK ARBITRATION TIMING IN MASTER TRANSMIT MODE BRG overflow, Release SCL, If SCL = 1 Load BRG with SSPADD<6:0>, and start count to measure high time interval BRG overflow occurs, Release SCL, Slave device holds SCL low. SCL = 1 BRG starts counting clock high interval. SCL SCL line sampled once every machine cycle (TOSC * 4). Hold off BRG until SCL is sampled high. SDA TBRG DS41120A-page 102 TBRG Advanced Information TBRG 1999 Microchip Technology Inc. PIC16C717/770/771 9.2.18 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 SDA pin, arbitration takes place when the master outputs a '1' on SDA by letting SDA float high and another master asserts a '0'. When the SCL pin floats high, data should be stable. If the expected data on SDA is a '1' and the data sampled on the SDA pin = '0', then a bus collision has taken place. The master will set the Bus Collision Interrupt Flag, BCLIF, and reset the I2C port to its IDLE state. (Figure 9-31). If a transmit was in progress when the bus collision occurred, the transmission is halted, the BF flag is cleared, the SDA and SCL lines are de-asserted, and the SSPBUF 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 SDA and SCL lines are de-asserted, and the respective control bits in the SSPCON2 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 SDA and SCL pins, and if a STOP condition occurs, the SSPIF bit will be set. A write to the SSPBUF will start the transmission of data at the first data bit, regardless of where the transmitter left off when 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 SSPSTAT register, or the bus is idle and the S and P bits are cleared. FIGURE 9-31: BUS COLLISION TIMING FOR TRANSMIT AND ACKNOWLEDGE Data changes while SCL = 0 SDA line pulled low by another source SDA released by master Sample SDA. While SCL is high data doesn't match what is driven by the master. Bus collision has occurred. SDA SCL Set bus collision interrupt. BCLIF 1999 Microchip Technology Inc. Advanced Information DS41120A-page 103 PIC16C717/770/771 9.2.18.1 BUS COLLISION DURING A START CONDITION During a START condition, a bus collision occurs if: a) SDA or SCL are sampled low at the beginning of the START condition (Figure 9-32). SCL is sampled low before SDA is asserted low. (Figure 9-33). b) During a START condition both the SDA and the SCL pins are monitored. If: while SDA is high, a bus collision occurs, because it is assumed that another master is attempting to drive a data '1' during the START condition. If the SDA pin is sampled low during this count, the BRG is reset and the SDA line is asserted early (Figure 9-34). If however a '1' is sampled on the SDA pin, the SDA pin is asserted low at the end of the BRG count. The baud rate generator is then reloaded and counts down to 0, and during this time, if the SCL pins is sampled as '0', a bus collision does not occur. At the end of the BRG count the SCL pin is asserted low. Note: the SDA pin is already low or the SCL pin is already low, then: the START condition is aborted, and the BCLIF flag is set, and the SSP module is reset to its IDLE state (Figure 9-32). The START condition begins with the SDA and SCL pins de-asserted. When the SDA pin is sampled high, the baud rate generator is loaded from SSPADD<6:0> and counts down to 0. If the SCL pin is sampled low 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 SDA 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. FIGURE 9-32: BUS COLLISION DURING START CONDITION (SDA ONLY) SDA goes low before the SEN bit is set. Set BCLIF, S bit and SSPIF set because SDA = 0, SCL = 1 SDA SCL Set SEN, enable start condition if SDA = 1, SCL=1 SEN cleared automatically because of bus collision. SSP module reset into idle state. SEN BCLIF SDA sampled low before START condition. Set BCLIF. S bit and SSPIF set because SDA = 0, SCL = 1 SSPIF and BCLIF are cleared in software. S SSPIF SSPIF and BCLIF are cleared in software. DS41120A-page 104 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 FIGURE 9-33: BUS COLLISION DURING START CONDITION (SCL = 0) SDA = 0, SCL = 1 TBRG TBRG SDA Set SEN, enable start sequence if SDA = 1, SCL = 1 SCL SCL = 0 before SDA = 0, Bus collision occurs, Set BCLIF. SEN SCL = 0 before BRG time out, Bus collision occurs, Set BCLIF. BCLIF Interrupts cleared in software. S '0' '0' SSPIF '0' '0' FIGURE 9-34: BRG RESET DUE TO SDA COLLISION DURING START CONDITION SDA = 0, SCL = 1 Set S Less than TBRG SDA Set SSPIF TBRG SDA pulled low by other master. Reset BRG and assert SDA SCL s SCL pulled low after BRG Timeout SEN BCLIF '0' Set SEN, enable start sequence if SDA = 1, SCL = 1 S SSPIF SDA = 0, SCL = 1 Set SSPIF 1999 Microchip Technology Inc. Advanced Information Interrupts cleared in software. DS41120A-page 105 PIC16C717/770/771 9.2.18.2 BUS COLLISION DURING A REPEATED START CONDITION however SDA is sampled high, then the BRG is reloaded and begins counting. If SDA goes from high to low before the BRG times out, no bus collision occurs, because no two masters can assert SDA at exactly the same time. During a Repeated Start condition, a bus collision occurs if: a) b) A low level is sampled on SDA when SCL goes from low level to high level. SCL goes low before SDA is asserted low, indicating that another master is attempting to transmit a data '1'. If, however, SCL goes from high to low before the BRG times out and SDA has not already been asserted, then a bus collision occurs. In this case, another master is attempting to transmit a data '1' during the Repeated Start condition. When the user de-asserts SDA and the pin is allowed to float high, the BRG is loaded with SSPADD<6:0>, and counts down to 0. The SCL pin is then deasserted, and when sampled high, the SDA pin is sampled. If SDA is low, a bus collision has occurred (i.e. another master is attempting to transmit a data '0'). If If at the end of the BRG time out both SCL and SDA are still high, the SDA pin is driven low, the BRG is reloaded, and begins counting. At the end of the count, regardless of the status of the SCL pin, the SCL pin is driven low and the Repeated Start condition is complete (Figure 9-35). FIGURE 9-35: BUS COLLISION DURING A REPEATED START CONDITION (CASE 1) SDA SCL Sample SDA when SCL goes high. If SDA = 0, set BCLIF and release SDA and SCL RSEN BCLIF S '0' Cleared in software '0' SSPIF '0' '0' FIGURE 9-36: BUS COLLISION DURING REPEATED START CONDITION (CASE 2) TBRG TBRG SDA SCL SCL goes low before SDA, Set BCLIF. Release SDA and SCL BCLIF Interrupt cleared in software RSEN S '0' '0' SSPIF '0' '0' DS41120A-page 106 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 9.2.18.3 BUS COLLISION DURING A STOP CONDITION The STOP condition begins with SDA asserted low. When SDA is sampled low, the SCL pin is allow to float. When the pin is sampled high (clock arbitration), the baud rate generator is loaded with SSPADD<6:0> and counts down to 0. After the BRG times out SDA is sampled. If SDA is sampled low, a bus collision has occurred. This is due to another master attempting to drive a data '0'. If the SCL pin is sampled low before SDA is allowed to float high, a bus collision occurs. This is another case of another master attempting to drive a data '0' (Figure 9-37). Bus collision occurs during a STOP condition if: a) b) After the SDA pin has been de-asserted and allowed to float high, SDA is sampled low after the BRG has timed out. After the SCL pin is de-asserted, SCL is sampled low before SDA goes high. FIGURE 9-37: BUS COLLISION DURING A STOP CONDITION (CASE 1) TBRG TBRG TBRG SDA sampled low after TBRG, Set BCLIF SDA SDA asserted low SCL PEN BCLIF P '0' '0' SSPIF '0' '0' FIGURE 9-38: BUS COLLISION DURING A STOP CONDITION (CASE 2) TBRG TBRG TBRG SDA Assert SDA SCL SCL goes low before SDA goes high Set BCLIF PEN BCLIF P '0' SSPIF '0' 1999 Microchip Technology Inc. Advanced Information DS41120A-page 107 PIC16C717/770/771 9.2.19 CONNECTION CONSIDERATIONS FOR I2C BUS VOL max = 0.4V at 3 mA, Rp min = (5.5-0.4)/0.003 = 1.7 k. VDD as a function of Rp is shown in Figure 9-39. The desired noise margin of 0.1VDD for the low level limits the maximum value of Rs. Series resistors are optional and used to improve ESD susceptibility. For standard-mode I2C bus devices, the values of resistors Rp and Rs in Figure 9-39 depends on the following parameters The bus capacitance is the total capacitance of wire, connections, and pins. This capacitance limits the maximum value of Rp due to the specified rise time (Figure 9-39). * Supply voltage * Bus capacitance * Number of connected devices (input current + leakage current). The SMP bit is the slew rate control enabled bit. This bit is in the SSPSTAT register, and controls the slew rate of the I/O pins when in I2C mode (master or slave). The supply voltage limits the minimum value of resistor Rp due to the specified minimum sink current of 3 mA at VOL max = 0.4V for the specified output stages. For example, with a supply voltage of VDD = 5V+10% and FIGURE 9-39: SAMPLE DEVICE CONFIGURATION FOR I2C BUS VDD + 10% RP DEVICE RP RS RS SDA SCL Cb=10 pF to 400 pF Note: I2C devices with input levels related to VDD must have one common supply line to which the pull-up resistor is also connected. TABLE 9-3: REGISTERS ASSOCIATED WITH I2C OPERATION Address Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 POR, BOR MCLR, WDT 0Bh, 8Bh, 10Bh,18Bh INTCON GIE PEIE T0IE INTE RBIE T0IF INTF RBIF 0000 000x 0000 000u 0Ch PIR1 -- ADIF -- -- SSPIF CCP1IF TMR2IF TMR1IF -0-- 0000 -0-- 0000 8Ch PIE1 -- ADIE -- -- SSPIE CCP1IE TMR2IE TMR1IE -0-- 0000 -0-- 0000 0Dh PIR2 LVDIF -- -- -- BCLIF -- -- CCP2IF 0--- 0--0 0--- 0--0 8Dh PIE2 LVDIE -- -- -- BCLIE -- -- CCP2IE 0--- 0--0 0--- 0--0 13h SSPBUF xxxx xxxx uuuu uuuu 14h SSPCON WCOL SSPOV SSPEN CKP SSPM3 SSPM2 SSPM1 SSPM0 0000 0000 0000 0000 91h SSPCON2 GCEN ACKSTAT ACKDT ACKEN RCEN PEN RSEN SEN 0000 0000 0000 0000 94h SSPSTAT SMP CKE D/A P S R/W UA BF 0000 0000 0000 0000 Synchronous Serial Port Receive Buffer/Transmit Register Legend: x = unknown, u = unchanged, - = unimplemented read as '0'. Shaded cells are not used by the MSSP in I2C mode. DS41120A-page 108 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 10.0 VOLTAGE REFERENCE MODULE AND LOW-VOLTAGE DETECT The Voltage Reference module provides reference voltages for the Brown-out Reset circuitry, the Low-voltage Detect circuitry and the A/D converter. The source for the reference voltages comes from the bandgap reference circuit. The bandgap circuit is energized anytime the reference voltage is required by the other sub-modules, and is powered down when not in use. The control registers for this module are LVDCON and REFCON, as shown in Register 10-1 and Figure 10-2. REGISTER 10-1: LOW-VOLTAGE DETECT CONTROL REGISTER (LVDCON: 9Ch) U-0 -- bit7 U-0 -- R-0 BGST R/W-0 LVDEN R/W-0 LV3 R/W-1 LV2 R/W-0 LV1 R/W-1 LV0 bit0 R = Readable bit W = Writable bit U = Unimplemented bit, read as `0' - n = Value at POR reset bit 7-6: Unimplemented: Read as '0' bit 5: BGST: Bandgap Stable Status Flag bit 1 = Indicates that the bandgap voltage is stable, and LVD interrupt is reliable 0 = Indicates that the bandgap voltage is not stable, and LVD interrupt should not be enabled bit 4: LVDEN: Low-voltage Detect Power Enable bit 1 = Enables LVD, powers up bandgap circuit and reference generator 0 = Disables LVD, powers down bandgap circuit if unused by BOR or VRH/VRL bit 3-0: LV<3:0>: Low Voltage Detection Limit bits (1) 1111 = External analog input is used 1110 = 4.5V 1101 = 4.2V 1100 = 4.0V 1011 = 3.8V 1010 = 3.6V 1001 = 3.5V 1000 = 3.3V 0111 = 3.0V 0110 = 2.8V 0101 = 2.7V 0100 = 2.5V 0011 = Reserved. Do not use. 0010 = Reserved. Do not use. 0001 = Reserved. Do not use. 0000 = Reserved. Do not use. Note 1: These are the minimum trip points for the LVD. See Table 15-3 for the trip point tolerances. Selection of reserved setting may result in an inadvertent interrupt. 1999 Microchip Technology Inc. Advanced Information DS41120A-page 109 PIC16C717/770/771 REGISTER 10-2: VOLTAGE REFERENCE CONTROL REGISTER (REFCON: 9BH) R/W-0 VRHEN bit7 R/W-0 VRLEN R/W-0 VRHOEN R/W-0 VRLOEN U-0 -- U-0 -- U-0 -- U-0 -- bit0 R = Readable bit W = Writable bit U = Unimplemented bit, read as `0' - n = Value at POR reset bit 7: VRHEN: Voltage Reference High Enable bit (VRH = 4.096V nominal) 1 = Enabled, powers up reference generator 0 = Disabled, powers down reference generator if unused by LVD, BOR, or VRL bit 6: VRLEN: Voltage Reference Low Enable bit (VRL = 2.048V nominal) 1 = Enabled, powers up reference generator 0 = Disabled, powers down reference generator if unused by LVD, BOR, or VRH bit 5: VRHOEN: High Voltage Reference Output Enable bit 1 = Enabled, VRH analog reference is output on RA3 if enabled (VRHEN = 1) 0 = Disabled, analog reference is used internally only bit 4: VRLOEN: Low Voltage Reference Output Enable bit 1 = Enabled, VRL analog reference is output on RA2 if enabled (VRLEN = 1) 0 = Disabled, analog reference is used internally only bit 3-0: Unimplemented: Read as '0' 10.1 Bandgap Voltage Reference The bandgap module generates a stable voltage reference of over a range of temperatures and device supply voltages. This module is enabled anytime any of the following are enabled: * Brown-out Reset * Low-voltage Detect * Either of the internal analog references (VRH, VRL) Whenever the above are all disabled, the bandgap module is disabled and draws no current. 10.2 Internal VREF for A/D Converter The bandgap output voltage is used to generate two stable references for the A/D converter module. These references are enabled in software to provide the user with the means to turn them on and off in order to minimize current consumption. Each reference can be individually enabled. Each reference, if enabled, can be output on an external pin by setting the VRHOEN (high reference output enable) or VRLOEN (low reference output enable) control bit. If the reference is not enabled, the VRHOEN and VRLOEN bits will have no effect on the corresponding pin. The device specific pin can then be used as general purpose I/O. Note: If VRH or VRL is enabled and the other reference (VRL or VRH), the BOR, and the LVD modules are not enabled, the bandgap will require a start-up time before the bandgap reference is stable. Before using the internal VRH or VRL reference, ensure that the bandgap reference voltage is stable by monitoring the BGST bit in the LVDCON register. The voltage references will not be reliable until the bandgap is stable as shown by BGST being set. The VRH reference is enabled with control bit VRHEN (REFCON<7>). When this bit is set, the gain amplifier is enabled. After a specified start-up time a stable reference of 4.096V nominal is generated and can be used by the A/D converter as a reference input. The VRL reference is enabled by setting control bit VRLEN (REFCON<6>). When this bit is set, the gain amplifier is enabled. After a specified start up time a stable reference of 2.048V nominal is generated and can be used by the A/D converter as a reference input. Each voltage reference is available for external use via VRL and VRH pins. DS41120A-page 110 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 10.3 Low-voltage Detect (LVD) This module is used to generate an interrupt when the supply voltage falls below a specified "trip" voltage. This module operates completely under software control. This allows a user to power the module on and off to periodically monitor the supply voltage, and thus minimize total current consumption. FIGURE 10-1: BLOCK DIAGRAM OF LVD AND VOLTAGE REFERENCE CIRCUIT LVDCON VDD VRHEN + VRLEN generates LVDIF 16 to 1 MUX RA1/AN1/LVDIN LVDEN REFCON VRH BODEN BGAP VRL LVDEN The LVD module is enabled by setting the LVDEN bit in the LVDCON register. The "trip point" voltage is the minimum supply voltage level at which the device can operate before the LVD module asserts an interrupt. When the supply voltage is equal to or less than the trip point, the module will generate an interrupt signal setting interrupt flag bit LVDIF. If interrupt enable bit LVDIE was set, then an interrupt is generated. The LVD interrupt can wake the device from sleep. The "trip point" voltage is software programmable to any one of 16 values, five of which are reserved (See Figure 10-1). The trip point is selected by programming the LV<3:0> bits (LVDCON<3:0>). Note: The LVDIF bit can not be cleared until the supply voltage rises above the LVD trip point. If interrupts are enabled, clear the LVDIE bit once the first LVD interrupt occurs to prevent reentering the interrupt service routine immediately after exiting the ISR. If the bandgap reference voltage is previously unused by either the brown-out circuitry or the voltage reference circuitry, then the bandgap circuit requires a time to start-up and become stable before a low voltage condition can be reliably detected. The low-voltage interrupt flag is prevented from being set until the bandgap has reached a stable reference voltage. When the bandgap is stable the BGST (LVDCON<5>) bit is set indicating that the low-voltage interrupt flag bit is released to be set if VDD is equal to or less than the LVD trip point. 10.3.1 EXTERNAL ANALOG VOLTAGE INPUT The LVD 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 LV<3:0> = 1111. When these bits are set the comparator input is multiplexed from an external input pin (RA1/AN1/LVDIN). Once the LV bits have been programmed for the specified trip voltage, the low-voltage detect circuitry is then enabled by setting the LVDEN (LVDCON<4>) bit. 1999 Microchip Technology Inc. Advanced Information DS41120A-page 111 PIC16C717/770/771 NOTES: DS41120A-page 112 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 11.0 ANALOG-TO-DIGITAL CONVERTER (A/D) MODULE The analog-to-digital (A/D) converter module has six inputs for the PIC16C717/770/771. The PIC16C717 analog-to-digital converter (A/D) allows conversion of an analog input signal to a corresponding 10-bit digital value, while the A/D converter in the PIC16C770/771 allows conversion to a corresponding 12-bit digital value. The A/D module has up to 6 analog inputs, which are multiplexed into one sample and hold. The output of the sample and hold is the input into the converter, which generates the result via successive approximation. The analog reference voltages are software selectable to either the device's analog positive and negative supply voltages (AVDD/ AVSS), the voltage level on the VREF+ and VREF- pins, or internal voltage references if enabled (VRH, VRL). The A/D converter can be triggered by setting the GO/ DONE bit, or by the special event compare mode of the ECCP1 module. When conversion is complete, the GO/DONE bit returns to '0', the ADIF bit in the PIR1 register is set, and an A/D interrupt will occur, if enabled. The A/D converter has a unique feature of being able to 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. 1999 Microchip Technology Inc. The A/D module has four registers. These registers are: * * * * A/D Result Register Low ADRESL A/D Result Register High ADRESH A/D Control Register 0 (ADCON0) A/D Control Register 1 (ADCON1) A device reset forces all registers to their reset state. This forces the A/D module to be turned off and any conversion is aborted. 11.1 Control Registers The ADCON0 register, shown in Register 11-1, controls the operation of the A/D module. The ADCON1 register, shown in Register 11-2, configures the functions of the port pins, the voltage reference configuration and the result format. The port pins can be configured as analog inputs or as digital I/O. The combination of the ADRESH and ADRESL registers contain the result of the A/D conversion. The register pair is referred to as the ADRES register. When the A/D conversion is complete, the result is loaded into ADRES, the GO/DONE bit (ADCON0<2>) is cleared, and the A/D interrupt flag ADIF is set. The block diagram of the A/D module is shown in Figure 11-3. Advanced Information DS41120A-page 113 PIC16C717/770/771 REGISTER 11-1: A/D CONTROL REGISTER 0 (ADCON0: 1Fh). R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 ADCS1 ADCS0 CHS2 CHS1 CHS0 GO/DONE CHS3 ADON bit7 bit 0 R= W= -n= Readable bit Writable bit Value at POR reset bit 7-6: ADCS<1:0>: A/D Conversion Clock Select bits If internal VRL and/or VRH are not used for A/D reference (VCFG<2:0> = 000, 001, 011 or 101): 00 = FOSC/2 01 = FOSC/8 10 = FOSC/32 11 = FRC (clock derived from a dedicated RC oscillator = 1 MHz max) If internal VRL and/or VRH are used for A/D reference (VCFG<2:0> = 010, 100, 110 or 111): 00 = FOSC/16 01 = FOSC/64 10 = FOSC/256 11 = FRC (clock derived from a dedicated RC oscillator = 125 kHz max) bit 1,5-3: CHS:<3:0>: Analog Channel Select bits 0000 = channel 00 (AN0) 0001 = channel 01 (AN1) 0010 = channel 02 (AN2) 0011 = channel 03 (AN3) 0100 = channel 04 (AN4) 0101 = channel 05 (AN5) 0110 = reserved, do not select 0111 = reserved, do not select 1000 = reserved, do not select 1001 = reserved, do not select 1010 = reserved, do not select 1011 = reserved, do not select 1100 = reserved, do not select 1101 = reserved, do not select 1110 = reserved, do not select 1111 = reserved, do not select bit 2: GO/DONE: A/D Conversion Status bit 1 = A/D conversion cycle in progress. Setting this bit starts an A/D conversion cycle. This bit is automatically cleared by hardware when the A/D conversion has completed. 0 = A/D conversion completed/not in progress bit 0: ADON: A/D On bit 1 = A/D converter module is operating 0 = A/D converter is shutoff and consumes no operating current DS41120A-page 114 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 REGISTER 11-2: A/D CONTROL REGISTER 1 (ADCON1: 9Fh) R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 ADFM VCFG2 VCFG1 VCFG0 R/W-0 R/W-0 Reserved bit7 bit 0 bit 7: ADFM: A/D Result Format Select bit 1 = Right justified 0 = Left justified bit 6-4: VCFG<2:0>: Voltage reference configuration bits bit 3-0: R/W-0 A/D VREF+ A/D VREF- 000 AVDD AVSS 001 External VREF+ External VREF- 010 Internal VRH Internal VRL 011 External VREF+ AVSS 100 Internal VRH AVSS 101 AVDD External VREF- 110 AVDD Internal VRL 111 Internal VRL AVSS R= W= U= -n= Readable bit Writable bit Unimplemented bit, read as `0' Value at POR reset Reserved: Do not use. The value that is in the ADRESH and ADRESL registers are not modified for a Power-on Reset. The ADRESH and ADRESL registers will contain unknown data after a Power-on Reset. The A/D conversion results can be left justified (ADFM bit cleared), or right justified (ADFM bit set). Figure 11-1 through Figure 11-2 show the A/D result data format of the PIC16C717/770/771. FIGURE 11-1: PIC16C770/771 12-BIT A/D RESULT FORMATS ADRESH (1Eh) Left Justified (ADFM = 0) ADRESL (9Eh) MSB LSB bit7 bit7 12-bit A/D Result Right Justified (ADFM = 1) Unused MSB bit7 LSB bit7 Unused 1999 Microchip Technology Inc. 12-bit A/D Result Advanced Information DS41120A-page 115 PIC16C717/770/771 FIGURE 11-2: PIC16C717 10-BIT A/D RESULT FORMAT (ADFM = 0) MSB LSB bit7 bit7 10-bit A/D Result Unused MSB (ADFM = 1) LSB bit7 bit7 Unused 10-bit A/D Result After the A/D module has been configured as desired, the selected channel must be acquired before the conversion is started. The analog input channels must have their corresponding TRIS and ANSEL bits selected as an input. To determine acquisition time, see Section 11.6. After this acquisition time has elapsed, the A/D conversion can be started. The following steps should be followed for doing an A/D conversion: 11.2 Configuring the A/D Module 11.2.1 CONFIGURING ANALOG PORT PINS The ANSEL and TRIS registers control the operation of the A/D port pins. The port pins that are desired as analog inputs must have their corresponding TRIS bit set (input). If the TRIS bit is cleared (output), the digital output level (VOH or VOL) will be converted. The proper ANSEL bits must be set (analog input) to disable the digital input buffer. 11.2.2 Unused CONFIGURING THE REFERENCE VOLTAGES The VCFG bits in the ADCON1 register configure the A/D module reference inputs. The reference high input can come from an internal reference (VRH) or (VRL), an external reference (VREF+), or AVDD. The low reference input can come from an internal reference (VRL), an external reference (VREF-), or AVSS. If an external reference is chosen for the reference high or reference low inputs, the port pin that multiplexes the incoming external references is configured as an analog input, regardless of the values contained in the A/D port configuration bits (PCFG<3:0>). The A/D operation is independent of the state of the TRIS bits and the ANSEL bits. Note 1: When reading the PORTA or PORTB register, all pins configured as analog input channels will read as '0'. 2: Analog levels on any pin that is defined as a digital input, including the ANx pins, may cause the input buffer to consume current that is out of the devices specification. DS41120A-page 116 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 After the A/D module has been configured as desired and the analog input channels have their corresponding TRIS bits selected for port inputs, the selected channel must be acquired before conversion is started. The A/D conversion cycle can be initiated by setting the GO/DONE bit. The A/D conversion begins and lasts for 13TAD. The following steps should be followed for performing an A/D conversion: 1. 2. 3. Configure port pins: * Configure analog input mode (ANSEL) * Configure pin as input (TRISA or TRISB) Configure the A/D module * Configure A/D Result Format / voltage reference (ADCON1) * Select A/D input channel (ADCON0) * Select A/D conversion clock (ADCON0) * Turn on A/D module (ADCON0) Configure A/D interrupt (if required) * Clear ADIF bit * Set ADIE bit * Set PEIE bit * Set GIE bit 4. 5. 6. Wait the required acquisition time (3TAD) Start conversion * Set GO/DONE bit (ADCON0) Wait 13TAD until A/D conversion is complete, by either: * Polling for the GO/DONE bit to be cleared OR 7. 8. * Waiting for the A/D interrupt Read A/D Result registers (ADRESH and ADRESL), clear ADIF if required. For next conversion, go to step 1, step 2 or step 3 as required. Clearing the GO/DONE bit during a conversion will abort the current conversion. The ADRESH and ADRESL registers will be updated with the partially completed A/D conversion value. That is, the ADRESH and ADRESL registers will contain the value of the current incomplete conversion. Note: Do not set the ADON bit and the GO/ DONE bit in the same instruction. Doing so will cause the GO/DONE bit to be automatically cleared. FIGURE 11-3: A/D BLOCK DIAGRAM CHS<3:0> VAIN RB1/AN5/SS (Input voltage) RB0/AN4/INT RA3/AN3/VREF+/VRH RA2/AN2/VREF-/VRL RA1/AN1 AVDD VREF+ RA0/AN0 VRH VRL (Reference voltage +) VCFG<2:0> A/D Converter VREFVRL (Reference voltage -) AVSS VCFG<2:0> 1999 Microchip Technology Inc. Advanced Information DS41120A-page 117 PIC16C717/770/771 11.3 Selecting the A/D Conversion Clock The A/D conversion cycle requires 13TAD: 1 TAD for settling time, and 12 TAD for conversion. The source of the A/D conversion clock is software selected. If neither the internal VRH nor VRL are used for the A/D converter, the four possible options for TAD are: * * * * 2 TOSC 8 TOSC 32 TOSC A/D RC oscillator TABLE 11-1: If the VRH or VRL are used for the A/D converter reference, then the TAD requirement is automatically increased by a factor of 8. For correct A/D conversions, the A/D conversion clock (TAD) must be selected to ensure a minimum TAD time of 1.6 s. Table 11-1 shows the resultant TAD times derived from the device operating frequencies and the A/D clock source selected. The ADIF bit is set on the rising edge of the 14th TAD. The GO/DONE bit is cleared on the falling edge of the 14th TAD. TAD vs. DEVICE OPERATING FREQUENCIES A/D Reference Source A/D Clock Source (TAD) Operation 2 TOSC External VREF or 8 TOSC Analog Supply 32 TOSC A/D RC Internal VRH or 16 TOSC VRL 64 TOSC 256 TOSC A/D RC ADCS<1:0> 00 01 10 11 00 01 10 11 Device Frequency 20 MHz 100 ns(2) 800 ns(2) 1.6 s 2 - 6 s(1,4) 800 ns(2) 6.4 s(2) 12.8 s 16 - 48 s(4,5) 5 MHz 400 ns(2) 1.6 s 6.4 s 2 - 6 s(1,4) 3.2 s(2) 12.8 s 51.2 s 16 - 48 s(4,5) 4 MHz 500 ns(2) 2.0 s 8.0 s(3) 2 - 6 s(1,4) 4 s(2) 16 s 64 s(3) 16 - 48 s(4,5) 1.25 MHz 1.6 s 6.4 s 24 s(3) 2 - 6 s(1,4) 12.8 s 51.2 s 192 s(3) 16 - 48 s(4,5) Legend: Note 1: 2: 3: 4: Shaded cells are outside of recommended range. The A/D RC source has a typical TAD time of 4 s for VDD > 3.0V. These values violate the minimum required TAD time. For faster conversion times, the selection of another clock source is recommended. When the device frequency is greater than 1 MHz, the A/D RC clock source is only recommended if the conversion will be performed during sleep. 5: The resource has a typical TAD time of 32 s for VDD > 3.0V. DS41120A-page 118 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 11.4 A/D Conversions Example 11-1 shows an example that performs an A/D conversion. The port pins are configured as analog inputs. The analog reference VREF+ is the device AVDD and the analog reference VREF- is the device AVSS. The A/D interrupt is enabled and the A/D conversion clock is TRC. The conversion is performed on the AN0 channel. EXAMPLE 11-1: PERFORMING AN A/D CONVERSION BCF BSF CLRF MOVLW MOVWF MOVWF BSF BCF MOVLW PIR1, ADIF STATUS, RP0 ADCON1 0x01 ANSEL TRISA PIE1, ADIE STATUS, RP0 0xC1 MOVWF BSF BSF ADCON0 INTCON, PEIE INTCON, GIE ;Clear A/D Int Flag ;Select Bank 1 ;Configure A/D Voltage Reference ;disable AN0 digital input buffer ;RA0 is input mode ;Enable A/D interrupt ;Select Bank 0 ;RC clock, A/D is on, ;Ch 0 is selected ; ;Enable Peripheral ;Enable All Interrupts ; ; Ensure that the required sampling time for the ; selected input channel has lapsed. Then the ; conversion may be started. BSF ADCON0, GO ;Start A/D Conversion : ;The ADIF bit will be ;set and the GO/DONE bit : ;cleared upon completion;of the A/D conversion. ; Wait for A/D completion and read ADRESH:ADRESL for result. 1999 Microchip Technology Inc. Advanced Information DS41120A-page 119 PIC16C717/770/771 11.5 A/D Converter Module Operation Figure 11-4 shows the flowchart of the A/D converter module. FIGURE 11-4: FLOWCHART OF A/D OPERATION ADON = 0 Yes ADON = 0? No Sample Selected Channel Yes GO = 0? No A/D Clock = RC? Yes Start of A/D Conversion Delayed 1 Instruction Cycle Finish Conversion GO = 0 ADIF = 1 No No SLEEP Yes Instruction? SLEEP Yes Instruction? Abort Conversion GO = 0 ADIF = 0 Finish Conversion GO = 0 ADIF = 1 Wake-up Yes From Sleep? No No Finish Conversion GO = 0 ADIF = 1 Wait 2 Tad SLEEP Power down A/D Wait 2 Tad Stay in Sleep Powerdown A/D Wait 2 Tad DS41120A-page 120 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 11.6 A/D Sample Requirements 11.6.1 RECOMMENDED SOURCE IMPEDANCE The maximum recommended impedance for analog sources is 2.5 k. This value is calculated based on the maximum leakage current of the input pin. The leakage current is 100 nA max., and the analog input voltage cannot be varied by more than 1/4 LSb or 250 V due to leakage. This places a requirement on the input impedance of 250 V/100 nA = 2.5 k. 11.6.2 SAMPLING TIME CALCULATION 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 11-5. 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), see Figure 11-5. The maximum recommended impedance for analog sources is 2.5 k . After the analog input channel is selected (changed) this sampling must be done before the conversion can be started. To calculate the minimum sampling time, Equation 112 may be used. This equation assumes that 1/4 LSb error is used (16384 steps for the A/D). The 1/4 LSb error is the maximum error allowed for the A/D to meet its specified resolution. The CHOLD is assumed to be 25 pF for the 12-bit A/D. EXAMPLE 11-2: A/D SAMPLING TIME EQUATION VHOLD =(VREF - VREF/16384) = (VREF) * (1 -e (-TC/C (RIC +RSS + RS)) VREF(1 - 1/16384) = VREF * (1 -e (-TC/C (RIC +RSS + RS)) Tc = -CHOLD (1k + RSS + RS) In (1/16384) Figure 11-3 shows the calculation of the minimum time required to charge CHOLD. This calculation is based on the following system assumptions: CHOLD = 25 pF RS = 2.5 k 1/4 LSb error VDD = 5V RSS = 10 k (worst case) Temp (system Max.) = 50C Note 1: The reference voltage (VREF) has no effect on the equation, since it cancels itself out. 2: The charge holding capacitor (CHOLD) is not discharged after each conversion. 3: The maximum recommended impedance for analog sources is 2.5 k . This is required to meet the pin leakage specification. 4: After a conversion has completed, you must wait 2 TAD time before sampling can begin again. During this time, the holding capacitor is not connected to the selected A/D input channel. 1999 Microchip Technology Inc. Advanced Information DS41120A-page 121 PIC16C717/770/771 EXAMPLE 11-3: CALCULATING THE MINIMUM REQUIRED SAMPLE TIME TACQ = TACQ = TC = TC = TC = TC = TC = TC = Amplifier Settling Time + Holding Capacitor Charging Time +Temperature offset 5 s + TC + [(Temp - 25C)(0.05 s/C)] Holding Capacitor Charging Time (CHOLD) (RIC + RSS + RS) In (1/16384) -25 pF (1 k +10 k + 2.5 k) In (1/16384) -25 pF (13.5 k) In (1/16384) -0.338 (-9.704)s 3.3s TACQ = 5 s + 3.3 s + [(50C - 25C)(0.05 s / C)] TACQ = TACQ = 8.3 s + 1.25 s 9.55 s The temperature coefficient is only required for temperatures > 25C. FIGURE 11-5: ANALOG INPUT MODEL VDD Rs Port Pin CPIN 5 pF VA Sampling Switch VT = 0.6V VT = 0.6V RIC 1k 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 SS CHOLD DS41120A-page 122 = interconnect resistance = sampling switch = sample/hold capacitance (from DAC) 6V 5V VDD 4V 3V 2V Advanced Information 5 6 7 8 9 10 11 Sampling Switch (RSS) ( k ) 1999 Microchip Technology Inc. PIC16C717/770/771 11.7 Use of the ECCP1 Trigger 11.9 An A/D conversion can be started by the "special event trigger" of the CCP module. This requires that the CCP1M<3:0> bits be programmed as 1011b and that the A/D module is enabled (ADON is set). When the trigger occurs, the GO/DONE bit will be set on Q2 to start the A/D conversion and the Timer1 counter will be reset to zero. Timer1 is reset to automatically repeat the A/D conversion cycle, with minimal software overhead (moving the ADRESH and ADRESL to the desired location). The appropriate analog input channel must be selected before the "special event trigger" sets the GO/DONE bit (starts a conversion cycle). If the A/D module is not enabled (ADON is cleared), then the "special event trigger" will be ignored by the A/D module, but will still reset the Timer1 counter. 11.8 Effects of a RESET A device reset forces all registers to their reset state. This forces the A/D module to be turned off, and any conversion is aborted. The value that is in the ADRESH and ADRESL registers are not modified. The ADRESH and ADRESL registers will contain unknown data after a Power-on Reset. Faster Conversion - Lower Resolution Trade-off Not all applications require a result with 12-bits of resolution, but may instead require a faster conversion time. The A/D module allows users to make the tradeoff of conversion speed to resolution. Regardless of the resolution required, the acquisition time is the same. To speed up the conversion, the A/D module may be halted by clearing the GO/DONE bit after the desired number of bits in the result have been converted. Once the GO/DONE bit has been cleared, all of the remaining A/D result bits are `0'. The equation to determine the time before the GO/DONE bit can be switched is as follows: Conversion time = (N+1)TAD Where: N = number of bits of resolution required, and 1TAD is the amplifier settling time. Since TAD is based from the device oscillator, the user must use some method (a timer, software loop, etc.) to determine when the A/D GO/DONE bit may be cleared. Table 11-4 shows a comparison of time required for a conversion with 4-bits of resolution, versus the normal 12-bit resolution conversion. The example is for devices operating at 20 MHz. The A/D clock is programmed for 32 TOSC. EXAMPLE 11-4: 4-BIT vs. 12-BIT CONVERSION TIME EXAMPLE 4 Bit Example: Conversion Time = (N + 1) TAD = (4 + 1) TAD = (5)(1.6 S) = 8 S 12 Bit Example: Conversion Time = (N + 1) TAD = (12 + 1) TAD = (13)(1.6 S) = 20.8 S 1999 Microchip Technology Inc. Advanced Information DS41120A-page 123 PIC16C717/770/771 11.10 A/D Operation During Sleep Turning off the A/D places the A/D module in its lowest current consumption state. The A/D module can operate during SLEEP mode. This requires that the A/D clock source be configured for RC (ADCS<1:0> = 11b). With the RC clock source selected, when the GO/DONE bit is set the A/D module waits one instruction cycle before starting the conversion cycle. This allows the SLEEP instruction to be executed, which eliminates all digital switching noise during the sample and conversion. When the conversion cycle is completed the GO/DONE bit is cleared, and the result loaded into the ADRESH and ADRESL registers. If the A/D interrupt is enabled, the device will wake-up from SLEEP. If the A/D interrupt is not enabled, the A/D module will then be turned off, although the ADON bit will remain set. When the A/D clock source is another clock option (not RC), a SLEEP instruction causes the present conversion to be aborted and the A/D module is turned off, though the ADON bit will remain set. TABLE 11-2: Note: 11.11 For the A/D module to operate in SLEEP, the A/D clock source must be configured to RC (ADCS<1:0> = 11b). Connection Considerations Since the analog inputs employ ESD protection, they have diodes to VDD and VSS. This requires that the analog input must be between VDD and VSS. If the input voltage exceeds this range by greater than 0.3V (either direction), one of the diodes becomes forward biased and it may damage the device if the input current specification is exceeded. An external RC filter is sometimes added for anti-aliasing of the input signal. The R component should be selected to ensure that the total source impedance is kept under the 2.5 k recommended specification. Any external components connected (via hi-impedance) to an analog input pin (capacitor, zener diode, etc.) should have very little leakage current at the pin. SUMMARY OF A/D REGISTERS Address Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Value on: POR, BOR Value on all other Resets 0Bh,8Bh, 10Bh,18Bh INTCON GIE PEIE T0IE INTE RBIE T0IF INTF RBIF 0000 000x 0000 000u 0Ch PIR1 -- ADIF -- -- SSPIF CCP1IF TMR2IF TMR1IF -0-- 0000 -0-- 0000 -- ADIE -- -- SSPIE CCP1IE TMR2IE TMR1IE -0-- 0000 -0-- 0000 uuuu uuuu 8Ch PIE1 1Eh ADRESH A/D High Byte Result Register xxxx xxxx 9Eh ADRESL A/D Low Byte Result Register xxxx xxxx uuuu uuuu 9Bh REFCON VRHEN 0000 ---- 0000 ---- 1Fh ADCON0 ADCS1 ADCS0 9Fh ADCON1 ADFM VCFG2 05h PORTA 06h PORTB 85h TRISA 86h TRISB 9Dh ANSEL VRLOEN -- -- -- -- CHS2 CHS1 CHS0 GO/DONE CHS3 ADON 0000 0000 0000 0000 VCFG1 VCFG0 -- -- -- -- 0000 ---- 0000 ---- PORTA Data Latch when written: PORTA pins when read 000x 0000 000u 0000 PORTB Data Latch when written: PORTB pins when read xxxx xx00 uuuu uu00 PORTA Data Direction Register 1111 1111 1111 1111 PORTB Data Direction Register 1111 1111 1111 1111 1111 1111 1111 1111 VRLEN VRHOEN ANS5 ANS4 ANS3 ANS2 ANS1 ANS0 Legend: x = unknown, u = unchanged, - = unimplemented read as '0'. Shaded cells are not used for A/D conversion. DS41120A-page 124 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 12.0 SPECIAL FEATURES OF THE CPU These devices have a host of features intended to maximize system reliability, minimize cost through elimination of external components, provide power saving operating modes and offer code protection. These are: * Oscillator Selection * Reset - Power-on Reset (POR) - Power-up Timer (PWRT) - Oscillator Start-up Timer (OST) - Brown-out Reset (BOR) * Interrupts * Watchdog Timer (WDT) * Low-voltage detection * SLEEP * Code protection * ID locations * In-circuit serial programming (ICSP) Some of the core features provided may not be necessary to each application that a device may be used for. The configuration word bits allow these features to be configured/enabled/disabled as necessary. These features include code protection, brown-out reset and its trippoint, the power-up timer, the watchdog timer and the devices oscillator mode. As can be seen in Figure 12-1, some additional configuration word bits have been provided for brown-out reset trippoint selection. These devices have a Watchdog Timer, which can be shut off only through configuration bits. It runs off its own RC oscillator for added reliability. There are two timers that offer necessary delays on power-up. One is the Oscillator Start-up Timer (OST), intended to keep the chip in reset until the crystal oscillator is stable. The other is the Power-up Timer (PWRT), which provides a fixed delay of 72 ms (nominal) on power-up type resets only (POR, BOR), designed to keep the part in reset while the power supply stabilizes. With these two timers on-chip, most applications need no external reset circuitry. SLEEP mode is designed to offer a very low current power-down mode. The user can wake-up from SLEEP through external reset, Watchdog Timer Wake-up, or through an interrupt. Several oscillator options are also made available to allow the part to fit the application. The INTRC and ER oscillator options save system cost while the LP crystal option saves power. A set of configuration bits are used to select various options. Additional information on special features is available in the PICmicroTM Mid-Range Reference Manual, (DS33023). 12.1 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 in program memory location 2007h. The user will note that address 2007h is beyond the user program memory space. In fact, it belongs to the special test/configuration memory space (2000h 3FFFh), which can be accessed only during programming. 1999 Microchip Technology Inc. Advanced Information DS41120A-page 125 PIC16C717/770/771 FIGURE 12-1: CONFIGURATION WORD FOR 16C717/770/771 DEVICE CP CP bit13 12 BORV1 BORV0 11 10 CP CP -- 9 8 7 BODEN MCLRE PWRTE 6 5 4 WDTE FOSC2 FOSC1 3 2 1 FOSC0 bit0 Register: Address CONFIG 2007h bit 13,12: CP: Program Memory Code Protection bit 9,8: 1 = Code protection off 0 = All program memory is protected(2) bit 11-10: BORV<1:0>: Brown-out Reset Voltage bits 00 = VBOR set to 4.5V 01 = VBOR set to 4.2V 10 = VBOR set to 2.7V 11 = VBOR set to 2.5V bit 7: Unimplemented: Read as '1' bit 6: BODEN: Brown-out Detect Reset Enable bit (1) 1 = Brown-out Detect Reset enabled 0 = Brown-out Detect Reset disabled bit 5: MCLRE: RA5/MCLR pin function select 1 = RA5/MCLR pin function is MCLR 0 = RA5/MCLR pin function is digital input, MCLR internally tied to VDD bit 4: PWRTE: Power-up Timer Enable bit (1) 1 = PWRT disabled 0 = PWRT enabled bit 3: WDTE: Watchdog Timer Enable bit 1 = WDT enabled 0 = WDT disabled bit 2-0: FOSC<2:0>: Oscillator Selection bits 000 = LP oscillator: Ceramic resonator on RA6/OSC2/CLKOUT and RA7/OSC1/CLKIN 001 = XT oscillator: Crystal on RA6/OSC2/CLKOUT and RA7/OSC1/CLKIN 010 = HS oscillator: High frequency crystal on RA6/OSC2/CLKOUT and RA7/OSC1/CLKIN 011 = EC: I/O function on RA6/OSC2/CLKOUT pin, CLKIN function on RA7/OSC1/CLKIN 100 = INTRC oscillator: I/O function on RA6/OSC2/CLKOUT pin, I/O function on RA7/OSC1/CLKIN 101 = INTRC oscillator: CLKOUT function on RA6/OSC2/CLKOUT pin, I/O function on RA7/OSC1/CLKIN 110 = ER oscillator: I/O function on RA6/OSC2/CLKOUT pin, Resistor on RA7/OSC1/CLKIN 111 = ER oscillator: CLKOUT function on RA6/OSC2/CLKOUT pin, Resistor on RA7/OSC1/CLKIN Note 1: Enabling Brown-out Reset automatically enables the Power-up Timer (PWRT), regardless of the value of bit PWRTE. Ensure the Power-up Timer is enabled anytime Brown-out Reset is enabled. 2: All of the CP bits must be given the same value to enable code protection. 12.2 Oscillator Configurations 12.2.2 12.2.1 OSCILLATOR TYPES In LP, XT or HS modes, a crystal or ceramic resonator is connected to the OSC1/CLKIN and OSC2/CLKOUT pins to establish oscillation (Figure 12-2). The PIC16C717/770/771 oscillator design requires the use of a parallel cut crystal. Use of a series cut crystal may give a frequency out of the crystal manufacturers specifications. The PIC16C717/770/771 can be operated in four different oscillator modes. The user can program three configuration bits (FOSC<2:0>) to select one of these eight modes: * * * * LP XT HS ER Low Power Crystal Crystal/Resonator High Speed Crystal/Resonator External Resistor (with and without CLKOUT) * INTRC Internal 4 MHz (with and without CLKOUT) * EC External Clock DS41120A-page 126 LP, XT AND HS MODES Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 FIGURE 12-2: CRYSTAL/CERAMIC RESONATOR OPERATION (HS, XT OR LP OSC CONFIGURATION) C1(1) OSC1 XTAL To internal logic RF(3) OSC2 SLEEP 12.2.3 EC MODE In applications where the clock source is external, the PIC16C717/770/771 should be programmed to select the EC (External Clock) mode. In this mode, the RA6/ OSC2/CLKOUT pin is available as an I/O pin. See Figure 12-3 for illustration. FIGURE 12-3: EXTERNAL CLOCK INPUT OPERATION (EC OSC CONFIGURATION) RS(2) PIC16C717/770/771 C2(1) Note1: See Table 12-1 and Table 12-2 for recommended values of C1 and C2. 2: A series resistor (RS) may be required for AT strip cut crystals. 3: RF varies with the crystal chosen. TABLE 12-1: OSC1 Clock from ext. system PIC16C717/770/771 I/O RA6 CERAMIC RESONATORS Ranges Tested: Mode XT Freq 455 kHz 2.0 MHz 4.0 MHz 8.0 MHz 16.0 MHz HS OSC1 68 - 100 pF 15 - 68 pF 15 - 68 pF 10 - 68 pF 10 - 22 pF OSC2 68 - 100 pF 15 - 68 pF 15 - 68 pF 10 - 68 pF 10 - 22 pF These values are for design guidance only. See notes at bottom of page. All resonators used did not have built-in capacitors. TABLE 12-2: Osc Type LP XT HS CAPACITOR SELECTION FOR CRYSTAL OSCILLATOR Crystal Freq Cap. Range C1 Cap. Range C2 32 kHz 33 pF 33 pF 200 kHz 15 pF 15 pF 200 kHz 47-68 pF 47-68 pF 1 MHz 15 pF 15 pF 4 MHz 15 pF 15 pF 4 MHz 15 pF 15 pF 8 MHz 15-33 pF 15-33 pF 20 MHz 15-33 pF 15-33 pF These values are for design guidance only. See notes at bottom of page. Note 1: Since each resonator/crystal has its own characteristics, the user should consult the resonator/crystal manufacturer for appropriate values of external components. 2: Higher capacitance increases the stability of oscillator but also increases the start-up time. 1999 Microchip Technology Inc. Advanced Information DS41120A-page 127 PIC16C717/770/771 12.2.4 ER MODE 12.2.6 For timing insensitive applications, the ER (External Resistor) clock mode offers additional cost savings. Only one external component, a resistor connected to the OSC1 pin and VSS, is needed to set the operating frequency of the internal oscillator. The resistor draws a DC bias current which controls the oscillation frequency. In addition to the resistance value, the oscillator frequency will vary from unit to unit, and as a function of supply voltage and temperature. Since the controlling parameter is a DC current and not a capacitance, the particular package type and lead frame will not have a significant effect on the resultant frequency. Figure 12-4 shows how the controlling resistor is connected to the PIC16C717/770/771. For Rext values below 38k ohms, the oscillator operation may become unstable, or stop completely. For very high Rext values (e.g. 1M), the oscillator becomes sensitive to noise, humidity and leakage. Thus, we recommend keeping Rext between 38k and 1M ohms. CLKOUT In the INTRC and ER modes, the PIC16C717/770/771 can be configured to provide a clock out signal by programming the configuration word. The oscillator frequency, divided by 4, can be used for test purposes or to synchronize other logic. In the INTRC and ER modes, if the CLKOUT output is enabled, CLKOUT is held low during reset. 12.2.7 DUAL SPEED OPERATION FOR ER AND INTRC MODES A software programmable dual speed oscillator is available in either ER or INTRC oscillator modes. This feature allows the applications to dynamically toggle the oscillator speed between normal and slow frequencies. The nominal slow frequency is 37KHz. In ER mode, the slow speed operation is fixed and does not vary with resistor size. Applications that require low current power savings, but cannot tolerate putting the part into sleep, may use this mode. FIGURE 12-4: EXTERNAL RESISTOR The OSCF bit in the PCON register is used to control dual speed mode. See the PCON Register, Register 2-8, for details. PIC16C717/770/771 When changing the INTRC or ER internal oscillator speed, there is a period of time when the processor is inactive. When the speed changes from fast to slow, the processor inactive period is in the range of 100 S to 300 S. For speed change from slow to fast, the processor is in active for 1.25 S to 3.25 S. RA6/OSC2/CLKOUT RA7/OSC1/CLKIN REXT The Electrical Specification section shows the relationship between the Rext resistance value and the operating frequency as well as frequency variations due to operating temperature for given Rext and VDD values. The ER oscillator mode has two options that control the OSC2 pin. The first allows it to be used as a general purpose I/O port. The other configures the pin as CLKOUT. The ER oscillator does not run during reset. 12.2.5 INTRC MODE The internal RC oscillator provides a fixed 4 MHz (nominal) system clock at VDD = 5V and 25C, see "Electrical Specifications" section for information on variation over voltage and temperature. The INTRC oscillator does not run during reset. DS41120A-page 128 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 12.3 Reset The PIC16C717/770/771 devices have several different resets. These resets are grouped into two classifications; power-up and non-power-up. The power-up type resets are the power-on and brown-out resets which assume the device VDD was below its normal operating range for the device's configuration. The nonpower up type resets assume normal operating limits were maintained before/during and after the reset. * * * * * Power-on Reset (POR) Programmable Brown-out Reset (PBOR) MCLR reset during normal operation MCLR reset during SLEEP WDT Reset (during normal operation) Some registers are not affected in any reset condition. Their status is unknown on a power-up reset and unchanged in any other reset. Most other registers are placed into an initialized state upon reset, however they are not affected by a WDT reset during sleep, because this is considered a WDT Wakeup, which is viewed as the resumption of normal operation. Several status bits have been provided to indicate which reset occurred (see Table 12-4). See Table 12-6 for a full description of reset states of all registers. A simplified block diagram of the on-chip reset circuit is shown in Figure 12-5. These devices have a MCLR noise filter in the MCLR reset path. The filter will detect and ignore small pulses. It should be noted that a WDT Reset does not drive MCLR pin low. FIGURE 12-5: SIMPLIFIED BLOCK DIAGRAM OF ON-CHIP RESET CIRCUIT External Reset MCLR SLEEP WDT Time-out Module VDD rise detect Power-on Reset VDD Programmable BODEN Brown-out S OST/PWRT OST Chip_Reset R 10-bit Ripple counter Q OSC1 PWRT Dedicated Oscillator 10-bit Ripple counter Enable PWRT Enable OST 1999 Microchip Technology Inc. Advanced Information DS41120A-page 129 PIC16C717/770/771 12.4 12.5 Power-On Reset (POR) A Power-on Reset pulse is generated on-chip when VDD rise is detected (in the range of 1.5V - 2.1V). To take advantage of the POR, just enable the internal MCLR feature. This will eliminate external RC components usually needed to create a Power-on Reset. A maximum rise time for VDD is specified. See Electrical Specifications for details. For a slow rise time, see Figure 12-6. Two delay timers, (PWRT on OST), have been provided which hold the device in reset after a POR (dependent upon device configuration) so that all operational parameters have been met prior to releasing the device to resume/begin normal operation. When the device starts normal operation (exits the reset condition), device operating parameters (voltage, frequency, 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. Brown-out Reset may be used to meet the startup conditions, or if necessary an external POR circuit may be implemented to delay end of reset for as long as needed. FIGURE 12-6: EXTERNAL POWER-ON RESET CIRCUIT (FOR SLOW VDD RAMP) VDD VDD D R1 MCLR PIC16C717/770/771 Note 1: External Power-on Reset circuit is required only if 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 voltage drop across R does not violate the device's electrical specification. 3: R1 = 100 to 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). DS41120A-page 130 The Power-up Timer provides a fixed TPWRT time-out on power-up type resets only. For a POR, the PWRT is invoked when the POR pulse is generated. For a BOR, the PWRT is invoked when the device exits the reset condition (VDD rises above BOR trippoint). The Powerup Timer operates on an internal RC oscillator. The chip is kept in reset as long as the PWRT is active. The PWRT's time delay is designed to allow VDD to rise to an acceptable level. A configuration bit is provided to enable/disable the PWRT for the POR only. For a BOR the PWRT is always available regardless of the configuration bit setting. The power-up time delay will vary from chip-to-chip due to VDD, temperature and process variation. See DC parameters for details. 12.6 Oscillator Start-up Timer (OST) The Oscillator Start-up Timer (OST) provides 1024 oscillator cycle (from OSC1 input) delay after the PWRT delay is over. This ensures that the crystal oscillator or resonator has started and stabilized. The OST time-out is invoked only for XT, LP and HS modes and only on a power-up type reset or a wake-up from SLEEP. 12.7 Programmable Brown-Out Reset (PBOR) The Programmable Brown-out Reset module is used to generate a reset when the supply voltage falls below a specified trip voltage. The trip voltage is configurable to any one of four voltages provided by the BORV<1:0> configuration word bits. R C Power-up Timer (PWRT) Configuration bit, BODEN, can disable (if clear/programmed) or enable (if set) the Brown-out Reset circuitry. If VDD falls below the specified trippoint for longer than TBOR, (parameter #35), the brown-out situation will reset the chip. A reset may not occur if VDD falls below the trippoint for less than TBOR. The chip will remain in Brown-out Reset until VDD rises above VBOR. The Power-up Timer will be invoked at that point and will keep the chip in RESET an additional TPWRT. If VDD drops below VBOR while the Power-up Timer is running, the chip will go back into a Brown-out Reset and the Power-up Timer will be re-initialized. Once VDD rises above VBOR, the Power-up Timer will again begin a TPWRT time delay. Even though the PWRT is always enabled when brown-out is enabled, the PWRT configuration word bit should be cleared (enabled) when brown-out is enabled. Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 12.8 Table 12-5 shows the reset conditions for some special function registers, while Table 12-6 shows the reset conditions for all the registers. Time-out Sequence On power-up, the time-out sequence is as follows: First PWRT time-out is invoked by the POR pulse. When the PWRT delay expires, the Oscillator Start-up Timer is activated. The total time-out will vary based on oscillator configuration and the status of the PWRT. For example, in RC mode with the PWRT disabled, there will be no time-out at all. Figure 12-7, Figure 12-8, Figure 12-9 and Figure 12-10 depict time-out sequences on power-up. 12.9 The Power Control/Status Register, PCON, has two status bits that provide indication of which power-up type reset occurred. Bit0 is Brown-out Reset Status bit, BOR. Bit BOR is set on a Power-on Reset. It must then be set by the user and checked on subsequent resets to see if bit BOR cleared, indicating a BOR occurred. However, if the brown-out circuitry is disabled, the BOR bit is a "Don't Care" bit and is considered unknown upon a POR. Since the time-outs occur from the POR pulse, if MCLR is kept low long enough, the time-outs will expire. Then bringing MCLR high will begin execution immediately (Figure 12-9). This is useful for testing purposes or to synchronize more than one PICmicro microcontroller operating in parallel. TABLE 12-3: Bit1 is POR (Power-on Reset Status bit). It is cleared on a Power-on Reset and unaffected otherwise. The user must set this bit following a Power-on Reset. TIME-OUT IN VARIOUS SITUATIONS Power-up Oscillator Configuration Brown-out Wake-up from SLEEP 1024TOSC TPWRT + 1024TOSC 1024TOSC -- TPWRT -- PWRTE = 0 PWRTE = 1 XT, HS, LP TPWRT + 1024TOSC EC, ER, INTRC TPWRT TABLE 12-4: Power Control/Status Register (PCON) STATUS BITS AND THEIR SIGNIFICANCE POR BOR TO PD 0 1 1 1 Power-on Reset 0 x 0 x Illegal, TO is set on POR 0 x x 0 Illegal, PD is set on POR 1 0 1 1 Brown-out Reset 1 1 0 1 WDT Reset 1 1 0 0 WDT Wake-up 1 1 u u MCLR Reset during normal operation 1 1 1 0 MCLR Reset during SLEEP or interrupt wake-up from SLEEP TABLE 12-5: RESET CONDITION FOR SPECIAL REGISTERS Program Counter STATUS Register PCON Register Power-on Reset 000h 0001 1xxx ---- 1-01 MCLR Reset during normal operation 000h 000u uuuu ---- 1-uu MCLR Reset during SLEEP 000h 0001 0uuu ---- 1-uu WDT Reset 000h 0000 1uuu ---- 1-uu PC + 1 uuu0 0uuu ---- u-uu 000h 0001 1uuu ---- 1-u0 Interrupt wake-up from SLEEP, GIE = 0 PC + 1 uuu1 0uuu ---- u-uu Interrupt wake-up from SLEEP, GIE = 1 0004h uuu1 0uuu ---- u-uu Condition WDT Wake-up Brown-out Reset Legend: u = unchanged, x = unknown, - = unimplemented bit read as '0'. 1999 Microchip Technology Inc. Advanced Information DS41120A-page 131 PIC16C717/770/771 TABLE 12-6: INITIALIZATION CONDITIONS FOR ALL REGISTERS Register Power-on Reset or Brown-out Reset MCLR Reset or WDT Reset Wake-up via WDT or Interrupt W xxxx xxxx uuuu uuuu uuuu uuuu INDF 0000 0000 uuuu uuuu uuuu uuuu TMR0 xxxx xxxx uuuu uuuu uuuu uuuu 0000h 0000h STATUS 0001 1xxx 000q quuu(2) uuuq quuu(2) FSR xxxx xxxx uuuu uuuu uuuu uuuu PORTA xxxx 0000 uuuu 0000 uuuu uuuu PORTB xxxx xx00 uuuu uu00 uuuu uu00 PCLATH ---0 0000 ---0 0000 ---u uuuu INTCON 0000 000x 0000 000u uuuu uuqq PIR1 -0-- 0000 -0-- 0000 -0-- uuuu PIR2 0--- 0--- 0--- 0--- q--- q--- TMR1L xxxx xxxx uuuu uuuu uuuu uuuu TMR1H xxxx xxxx uuuu uuuu uuuu uuuu T1CON --00 0000 --uu uuuu --uu uuuu TMR2 0000 0000 0000 0000 uuuu uuuu T2CON -000 0000 -000 0000 -uuu uuuu SSPBUF xxxx xxxx uuuu uuuu uuuu uuuu SSPCON 0000 0000 0000 0000 uuuu uuuu CCPR1L xxxx xxxx uuuu uuuu uuuu uuuu CCPR1H xxxx xxxx uuuu uuuu uuuu uuuu CCP1CON 0000 0000 0000 0000 uuuu uuuu ADRESH xxxx xxxx uuuu uuuu uuuu uuuu ADCON0 0000 0000 0000 0000 uuuu uuuu OPTION_REG 1111 1111 1111 1111 uuuu uuuu TRISA 1111 1111 1111 1111 uuuu uuuu TRISB 1111 1111 1111 1111 uuuu uuuu PIE1 -0-- 0000 -0-- 0000 -u-- uuuu PIE2 0--- 0--- 0--- 0--- u--- u--- PCON ---- 1-qq ---- 1-uu ---- u-uu PR2 1111 1111 1111 1111 1111 1111 SSPADD 0000 0000 0000 0000 uuuu uuuu SSPSTAT 0000 0000 0000 0000 uuuu uuuu WPUB 1111 1111 1111 1111 uuuu uuuu IOCB 1111 0000 1111 0000 uuuu uuuu P1DEL 0000 0000 0000 0000 uuuu uuuu REFCON 0000 ---- 0000 ---- uuuu ---- PCL PC + 1(1) Legend: u = unchanged, x = unknown, - = unimplemented bit, read as '0', q = value depends on condition Note 1: When the wake-up is due to an interrupt and the GIE bit is set, the PC is loaded with the interrupt vector (0004h). 2: See Table 12-5 for reset value for specific condition. DS41120A-page 132 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 TABLE 12-6: INITIALIZATION CONDITIONS FOR ALL REGISTERS (CONTINUED) Register Power-on Reset or Brown-out Reset MCLR Reset or WDT Reset Wake-up via WDT or Interrupt LVDCON --00 0101 --00 0101 --uu uuuu ANSEL 1111 1111 1111 1111 uuuu uuuu ADRESL xxxx xxxx uuuu uuuu uuuu uuuu ADCON1 0000 000 0000 0000 uuuu uuuu PMDATL xxxx xxxx uuuu uuuu uuuu uuuu PMADRL xxxx xxxx uuuu uuuu uuuu uuuu PMDATH --xx xxxx --uu uuuu --uu uuuu PMADRH ---- xxxx ---- uuuu ---- uuuu PMCON1 1--- ---0 1--- ---0 1--- ---0 Legend: u = unchanged, x = unknown, - = unimplemented bit, read as '0', q = value depends on condition Note 1: When the wake-up is due to an interrupt and the GIE bit is set, the PC is loaded with the interrupt vector (0004h). 2: See Table 12-5 for reset value for specific condition. FIGURE 12-7: TIME-OUT SEQUENCE ON POWER-UP (MCLR TIED TO VDD) VDD MCLR INTERNAL POR TPWRT PWRT TIME-OUT TOST OST TIME-OUT INTERNAL RESET 1999 Microchip Technology Inc. Advanced Information DS41120A-page 133 PIC16C717/770/771 FIGURE 12-8: TIME-OUT SEQUENCE ON POWER-UP (MCLR NOT TIED TO VDD): CASE 1 VDD MCLR INTERNAL POR TPWRT PWRT TIME-OUT TOST OST TIME-OUT INTERNAL RESET FIGURE 12-9: TIME-OUT SEQUENCE ON POWER-UP (MCLR NOT TIED TO VDD): CASE 2 VDD MCLR INTERNAL POR TPWRT PWRT TIME-OUT TOST OST TIME-OUT INTERNAL RESET FIGURE 12-10: SLOW VDD RISE TIME (MCLR TIED TO VDD) 5V VDD 0V MCLR INTERNAL POR TPWRT (1) PWRT TIME-OUT TOST OST TIME-OUT INTERNAL RESET Note 1: Time dependent on oscillator circuit DS41120A-page 134 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 12.10 Interrupts The devices have up to 11 sources of interrupt. The interrupt control register (INTCON) records individual interrupt requests in flag bits. It also has individual and global interrupt enable bits. Note: Individual interrupt flag bits are set regardless of the status of their corresponding mask bit or the GIE bit. A global interrupt enable bit, GIE (INTCON<7>), enables (if set) all un-masked interrupts or disables (if cleared) all interrupts. When bit GIE is enabled and an interrupt's flag bit and mask bit are set, the interrupt will vector immediately. Individual interrupts can be disabled through their corresponding enable bits in various registers. Individual interrupt bits are set, regardless of the status of the GIE bit. The GIE bit is cleared on reset. The "return from interrupt" instruction, RETFIE, exits the interrupt routine as well as sets the GIE bit, which re-enables interrupts. The RB0/INT pin interrupt, the RB port change interrupt and the TMR0 overflow interrupt flags are contained in the INTCON register. The peripheral interrupt flags are contained in the special function registers PIR1 and PIR2. The corresponding interrupt enable bits are contained in special function registers PIE1 and PIE2, and the peripheral interrupt enable bit is contained in special function register INTCON. When an interrupt is responded to, the GIE bit is cleared to disable any further interrupt, the return address is pushed onto the stack and the PC is loaded with 0004h. Once in the interrupt service routine the source(s) of the interrupt can be determined by polling the interrupt flag bits. The interrupt flag bit(s) must be cleared in software before re-enabling interrupts to avoid recursive interrupts. For external interrupt events, such as the INT pin or PORTB change interrupt, the interrupt latency will be three or four instruction cycles. The exact latency depends when the interrupt event occurs. The latency is the same for one or two cycle instructions. Individual interrupt flag bits are set regardless of the status of their corresponding mask bit or the GIE bit FIGURE 12-11: INTERRUPT LOGIC LVDIF LVDIE Wake-up (If in SLEEP mode) ADIF ADIE T0IF T0IE INTF INTE Interrupt to CPU RBIF RBIE SSPIF SSPIE CCP1IF CCP1IE PEIE GIE TMR2IF TMR2IE TMR1IF TMR1IE BCLIF BCLIE 1999 Microchip Technology Inc. Advanced Information DS41120A-page 135 PIC16C717/770/771 12.10.1 INT INTERRUPT 12.11 External interrupt on RB0/INT pin is edge triggered: either rising if bit INTEDG (OPTION_REG<6>) is set, or falling, if the INTEDG bit is clear. When a valid edge appears on the RB0/INT pin, flag bit INTF (INTCON<1>) is set. This interrupt can be disabled by clearing enable bit INTE (INTCON<4>). Flag bit INTF must be cleared in software in the interrupt service routine before re-enabling this interrupt. The INT interrupt can wake-up the processor from SLEEP, if bit INTE was set prior to going into SLEEP. The status of global interrupt enable bit GIE decides whether or not the processor branches to the interrupt vector following wake-up. See Section 12.13 for details on SLEEP mode. During an interrupt, only the PC is saved on the stack. At the very least, W and STATUS should be saved to preserve the context for the interrupted program. All registers that may be corrupted by the ISR, such as PCLATH or FSR, should be saved. 12.10.2 TMR0 INTERRUPT An overflow (FFh 00h) in the TMR0 register will set flag bit T0IF (INTCON<2>). The interrupt can be enabled/disabled by setting/clearing enable bit T0IE (INTCON<5>). (Section 2.2.2.3) 12.10.3 PORTB INTCON CHANGE An input change on PORTB<7:0> sets flag bit RBIF (INTCON<0>). The PORTB pin(s) which can individually generate interrupt is selectable in the IOCB register. The interrupt can be enabled/disabled by setting/ clearing enable bit RBIE (INTCON<4>). (Section 2.2.2.3) Context Saving During Interrupts Example 12-1 stores and restores the STATUS, W and PCLATH registers. The register, W_TEMP, is defined in Common RAM, the last 16 bytes of each bank that may be accessed from any bank. The STATUS_TEMP and PCLATH_TEMP are defined in bank 0. The example: a) b) c) d) e) f) g) Stores the W register. Stores the STATUS register in bank 0. Stores the PCLATH register in bank 0. Executes the ISR code. Restores the PCLATH register. Restores the STATUS register Restores W. Note that W_TEMP, STATUS_TEMP and PCLATH_TEMP are defined in the common RAM area (70h - 7Fh) to avoid register bank switching during context save and restore. EXAMPLE 12-1: SAVING STATUS, W, AND PCLATH REGISTERS IN RAM #define W_TEMP 0x70 #define STATUS_TEMP 0x71 #define PCLATH_TEMP 0x72 org 0x04 ; start at Interrupt Vector MOVWF W_TEMP ; Save W register MOVF STATUS,w MOVWF STATUS_TEMP ; save STATUS MOVF PCLATH,w MOVWF PCLATH_TEMP ; save PCLATH : (Interrupt Service Routine) : MOVF PCLATH_TEMP,w MOVWF PCLATH MOVF STATUS_TEMP,w MOVWF STATUS SWAPF W_TEMP,f ; SWAPF W_TEMP,w ; swapf loads W without affecting STATUS flags RETFIE DS41120A-page 136 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 12.12 The WDT can be permanently disabled by programming the configuration bit WDTE (Section 12.1)'0'. Watchdog Timer (WDT) The Watchdog Timer is a free running on-chip RC oscillator, which does not require any external components. This oscillator is in dependent from the processor clock. The WDT will run, even if the main clock of the device has been stopped, for example, by execution of a SLEEP instruction. WDT time-out period values may be found in the Electrical Specifications. Values for the WDT prescaler may be assigned using the OPTION_REG register. During normal operation, a WDT time-out generates a device RESET (Watchdog Timer Reset). If the device is in SLEEP mode, a WDT time-out causes the device to wake-up and continue with normal operation (Watchdog Timer Wake-up). The TO bit in the STATUS register will be cleared upon a Watchdog Timer time-out. Note: The CLRWDT and SLEEP instructions clear the WDT and the postscaler, if assigned to the WDT, and prevent it from timing out and generating a device RESET condition. Note: When a CLRWDT instruction is executed and the prescaler is assigned to the WDT, the prescaler count will be cleared, but the prescaler assignment is not changed. . FIGURE 12-12: WATCHDOG TIMER BLOCK DIAGRAM From TMR0 Clock Source (Figure 5-2) 0 WDT Timer Postscaler M 1 U X 8 PS<2:0>(1) 8 - to - 1 MUX PSA WDT Enable Bit(2) To TMR0 (Figure 5-2) 0 1 PSA(1) MUX Note 1: PSA and PS<2:0> are bits in the OPTION_REG register. 2: WDTE bit in the configuration word. TABLE 12-7: WDT Time-out SUMMARY OF WATCHDOG TIMER REGISTERS Address Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 2007h Config. bits(1) -- BODEN MCLRE PWRTE WDTE FOSC2 FOSC1 FOSC0 81h,181h OPTION_REG RBPU INTEDG T0CS T0SE PSA PS2 PS1 PS0 Legend: Shaded cells are not used by the Watchdog Timer. Note 1: See Figure 12-1 for the full description of the configuration word bits. 1999 Microchip Technology Inc. Advanced Information DS41120A-page 137 PIC16C717/770/771 12.13 Power-down Mode (SLEEP) Power-down mode is entered by executing a SLEEP instruction. If enabled, the Watchdog Timer will be cleared but keeps running, the PD bit (STATUS<3>) is cleared, the TO (STATUS<4>) bit is set, and the oscillator driver is turned off. The I/O ports maintain the status they had, before the SLEEP instruction was executed (driving high, low, or hi-impedance). For lowest current consumption in this mode, place all I/O pins at either VDD, or VSS, ensure no external circuitry is drawing current from the I/O pin, power-down the A/D, disable external clocks. Pull all I/O pins, that are hi-impedance inputs, high or low externally to avoid switching currents caused by floating inputs. The T0CKI input should also be at VDD or VSS for lowest current consumption. The contribution from on-chip pull-ups on PORTB should be considered. 12.13.1 WAKE-UP FROM SLEEP The device can wake up from SLEEP through one of the following events: 1. 2. 3. External reset input on MCLR pin. Watchdog Timer Wake-up (if WDT was enabled). Interrupt from INT pin, RB port change, or some Peripheral Interrupts. External MCLR Reset will cause a device reset. All other events are considered a continuation of program execution and cause a "wake-up". The TO and PD bits in the STATUS register can be used to determine the cause of device reset. The PD bit, which is set on power-up, is cleared when SLEEP is invoked. The TO bit is cleared if a WDT time-out occurred (and caused wake-up). set (enabled), the device executes the instruction after the SLEEP instruction and then branches to the interrupt address (0004h). In cases where the execution of the instruction following SLEEP is not desirable, the user should have a NOP after the SLEEP instruction. 12.13.2 WAKE-UP USING INTERRUPTS When global interrupts are disabled (GIE cleared) and any interrupt source has both its interrupt enable bit and interrupt flag bit set, one of the following will occur: * If the interrupt occurs before the execution of a SLEEP instruction, the SLEEP instruction will complete as a NOP. Therefore, the WDT and WDT postscaler will not be cleared, the TO bit will not be set and PD bits will not be cleared. * If the interrupt occurs during or after the execution of a SLEEP instruction, the device will immediately wake up from sleep. The SLEEP instruction will be completely executed before the wake-up. Therefore, the WDT and WDT postscaler will be cleared, the TO bit will be set and the PD bit will be cleared. Even if the flag bits were checked before executing a SLEEP instruction, it may be possible for flag bits to become set before the SLEEP instruction completes. To determine whether a SLEEP instruction executed, test the PD bit. If the PD bit is set, the SLEEP instruction was executed as a NOP. To ensure that the WDT is cleared, a CLRWDT instruction should be executed before a SLEEP instruction. The following peripheral interrupts can wake the device from SLEEP: 1. 2. 3. 4. 5. 6. 7. TMR1 interrupt. Timer1 must be operating as an asynchronous counter. CCP capture mode interrupt. Special event trigger (Timer1 in asynchronous mode using an external clock). SSP (Start/Stop) bit detect interrupt. SSP transmit or receive in slave mode (SPI/I2C). A/D conversion (when A/D clock source is RC). Low-voltage detect. Other peripherals cannot generate interrupts since during SLEEP, no on-chip clocks are present. When the SLEEP instruction is being executed, the next instruction (PC + 1) is pre-fetched. For the device to wake-up through an interrupt event, the corresponding interrupt enable bit must be set (enabled). Wake-up is regardless of the state of the GIE bit. If the GIE bit is clear (disabled), the device continues execution at the instruction after the SLEEP instruction. If the GIE bit is DS41120A-page 138 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 FIGURE 12-13: WAKE-UP FROM SLEEP THROUGH INTERRUPT Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 OSC1 Tost(1) CLKOUT(3) INT pin INTF flag (INTCON<1>) GIE bit (INTCON<7>) Interrupt Latency(2) Processor in SLEEP INSTRUCTION FLOW PC Instruction fetched Instruction executed Note 1: 2: 3: 12.14 PC Inst(PC) = SLEEP Inst(PC - 1) PC+1 PC+2 Inst(PC + 1) Inst(PC + 2) SLEEP Inst(PC + 1) 12.15 Dummy cycle 0004h 0005h Inst(0004h) Inst(0005h) Dummy cycle Inst(0004h) TOST = 1024TOSC (drawing not to scale) This delay applies to LP, XT and HS modes only. GIE = '1' assumed. In this case after wake- up, the processor jumps to the interrupt routine. If GIE = '0', execution will continue in-line. CLKOUT is not available in these osc modes, but shown here for timing reference. Program Verification/Code Protection If the code protection bit(s) have not been programmed, the on-chip program memory can be read out for verification purposes. Note: PC + 2 PC+2 Microchip does not recommend code protecting windowed devices. ID Locations Four memory locations (2000h - 2003h) are designated as ID locations where the user can store checksum or other code-identification numbers. These locations are not accessible during normal execution but are readable and writable during program/verify. It is recommended that only the 4 least significant bits of the ID location are used. 12.16 In-Circuit Serial Programming (ICSPTM) PIC16CXXX microcontrollers 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 complete details of serial programming, please refer to the In-Circuit Serial Programming (ICSPTM) Guide, (DS30277). For ROM devices, these values are submitted along with the ROM code. 1999 Microchip Technology Inc. Advanced Information DS41120A-page 139 PIC16C717/770/771 NOTES: DS41120A-page 140 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 13.0 INSTRUCTION SET SUMMARY Each PIC16CXXX instruction is a 14-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 PIC16CXX instruction set summary in Table 13-2 lists byte-oriented, bit-oriented, and literal and control operations. Table 13-1 shows the opcode field descriptions. For byte-oriented instructions, 'f' represents a file register designator and 'd' represents a destination designator. The file register designator specifies which file register is to be used by the instruction. The destination designator specifies where the result of the operation is to be placed. If 'd' is zero, the result is placed in the W register. If 'd' is one, the result is placed in the file register specified in the instruction. For bit-oriented instructions, 'b' represents a bit field designator which selects the number of the bit affected by the operation, while 'f' represents the number of the file in which the bit is located. Table 13-2 lists the instructions recognized by the MPASM assembler. Figure 13-1 shows the general formats that the instructions can have. Note: All examples use the following format to represent a hexadecimal number: 0xhh where h signifies a hexadecimal digit. FIGURE 13-1: GENERAL FORMAT FOR INSTRUCTIONS Byte-oriented file register operations 13 8 7 6 OPCODE d f (FILE #) Bit-oriented file register operations 13 10 9 7 6 OPCODE b (BIT #) f (FILE #) OPCODE FIELD DESCRIPTIONS Field Description f Register file address (0x00 to 0x7F) Working register (accumulator) b Bit address within an 8-bit file register k Literal field, constant data or label General x Don't care location (= 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. 13 PC Destination select; d = 0: store result in W, d = 1: store result in file register f. Default is d = 1 TO Time-out bit PD Power-down bit Literal and control operations 8 7 OPCODE 0 k (literal) k = 8-bit immediate value CALL and GOTO instructions only 13 Program Counter 0 b = 3-bit bit address f = 7-bit file register address W d 0 d = 0 for destination W d = 1 for destination f f = 7-bit file register address For literal and control operations, 'k' represents an eight or eleven bit constant or literal value. TABLE 13-1: To maintain upward compatibility with future PIC16CXXX products, do not use the OPTION and TRIS instructions. 11 OPCODE 10 0 k (literal) k = 11-bit immediate value The instruction set is highly orthogonal and is grouped into three basic categories: * Byte-oriented operations * Bit-oriented operations * Literal and control operations A description of each instruction is available in the PICmicroTM Mid-Range Reference Manual, (DS33023). All instructions are executed within one single instruction cycle, unless a conditional test is true or the program counter is changed as a result of an instruction. In this case, the execution takes two instruction cycles with the second cycle executed as a NOP. 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. 1999 Microchip Technology Inc. Advanced Information DS41120A-page 141 PIC16C717/770/771 TABLE 13-2: PIC16CXXX INSTRUCTION SET Mnemonic, Operands Description Cycles 14-Bit Opcode MSb LSb Status Affected Notes BYTE-ORIENTED FILE REGISTER OPERATIONS ADDWF ANDWF CLRF CLRW COMF DECF DECFSZ INCF INCFSZ IORWF MOVF MOVWF NOP RLF RRF SUBWF SWAPF XORWF f, d f, d f f, d f, d f, d f, d f, d f, d f, d f f, d f, d f, d f, d f, d Add W and f AND W with f Clear f Clear W Complement f Decrement f Decrement f, Skip if 0 Increment f Increment f, Skip if 0 Inclusive OR W with f Move f Move W to f No Operation Rotate Left f through Carry Rotate Right f through Carry Subtract W from f Swap nibbles in f Exclusive OR W with f 1 1 1 1 1 1 1(2) 1 1(2) 1 1 1 1 1 1 1 1 1 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0111 0101 0001 0001 1001 0011 1011 1010 1111 0100 1000 0000 0000 1101 1100 0010 1110 0110 dfff dfff lfff 0000 dfff dfff dfff dfff dfff dfff dfff lfff 0xx0 dfff dfff dfff dfff dfff ffff ffff ffff 0011 ffff ffff ffff ffff ffff ffff ffff ffff 0000 ffff ffff ffff ffff ffff C,DC,Z Z Z Z Z Z Z Z Z C C C,DC,Z Z 1,2 1,2 2 1,2 1,2 1,2,3 1,2 1,2,3 1,2 1,2 1,2 1,2 1,2 1,2 1,2 BIT-ORIENTED FILE REGISTER OPERATIONS BCF BSF BTFSC BTFSS f, b f, b f, b f, b Bit Clear f Bit Set f Bit Test f, Skip if Clear Bit Test f, Skip if Set 1 1 1 (2) 1 (2) 01 01 01 01 00bb 01bb 10bb 11bb bfff bfff bfff bfff ffff ffff ffff ffff 1 1 2 1 2 1 1 2 2 2 1 1 1 11 11 10 00 10 11 11 00 11 00 00 11 11 111x 1001 0kkk 0000 1kkk 1000 00xx 0000 01xx 0000 0000 110x 1010 kkkk kkkk kkkk 0110 kkkk kkkk kkkk 0000 kkkk 0000 0110 kkkk kkkk kkkk kkkk kkkk 0100 kkkk kkkk kkkk 1001 kkkk 1000 0011 kkkk kkkk 1,2 1,2 3 3 LITERAL AND CONTROL OPERATIONS ADDLW ANDLW CALL CLRWDT GOTO IORLW MOVLW RETFIE RETLW RETURN SLEEP SUBLW XORLW k k k k k k k k k Add literal and W AND literal with W Call subroutine Clear Watchdog Timer Go to address Inclusive OR literal with W Move literal to W Return from interrupt Return with literal in W Return from Subroutine Go into standby mode Subtract W from literal Exclusive OR literal with W C,DC,Z Z TO,PD Z TO,PD C,DC,Z Z Note 1: When an I/O register is modified as a function of itself ( e.g., MOVF PORTB, 1), 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'. 2: If this instruction is executed on the TMR0 register (and, where applicable, d = 1), the prescaler will be cleared if assigned to the Timer0 Module. 3: If Program Counter (PC) is modified or a conditional test is true, the instruction requires two cycles. The second cycle is executed as a NOP. DS41120A-page 142 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 13.1 Instruction Descriptions ADDLW Add Literal and W ANDWF AND W with f Syntax: [label] ADDLW Syntax: [label] ANDWF Operands: 0 k 255 Operands: 0 f 127 d [0,1] k f,d Operation: (W) + k (W) Status Affected: C, DC, Z Operation: (W) .AND. (f) (destination) Description: The contents of the W register are added to the eight bit literal 'k' and the result is placed in the W register. Status Affected: Z Description: AND the W register with register 'f'. If 'd' is 0, the result is stored in the W register. If 'd' is 1, the result is stored back in register 'f'. BCF Bit Clear f Syntax: [label] BCF Operands: 0 f 127 0b7 Operation: 0 (f<b>) Status Affected: None Description: Bit 'b' in register 'f' is cleared. BSF Bit Set f ADDWF Add W and f Syntax: [label] ADDWF Operands: 0 f 127 d [0,1] Operation: (W) + (f) (destination) Status Affected: C, DC, Z Description: Add the contents of the W register with register 'f'. If 'd' is 0, the result is stored in the W register. If 'd' is 1, the result is stored back in register 'f'. ANDLW AND Literal with W f,d Syntax: [label] ANDLW Operands: 0 k 255 Operation: (W) .AND. (k) (W) Status Affected: Description: f,b Syntax: [label] BSF Operands: 0 f 127 0b7 Z Operation: 1 (f<b>) The contents of W register are AND'ed with the eight bit literal 'k'. The result is placed in the W register. Status Affected: None Description: Bit 'b' in register 'f' is set. 1999 Microchip Technology Inc. k Advanced Information f,b DS41120A-page 143 PIC16C717/770/771 BTFSS Bit Test f, Skip if Set CLRF Clear f Syntax: [label] BTFSS f,b Syntax: [label] CLRF Operands: 0 f 127 0b<7 Operands: 0 f 127 Operation: Operation: skip if (f<b>) = 1 00h (f) 1Z Status Affected: None Status Affected: Z Description: If bit 'b' in register 'f' is '0', the next instruction is executed. If bit 'b' is '1', then the next instruction is discarded and a NOP is executed instead making this a 2TCY instruction. Description: The contents of register 'f' are cleared and the Z bit is set. BTFSC Bit Test, Skip if Clear CLRW Clear W Syntax: [label] BTFSC f,b Syntax: [ label ] CLRW Operands: 0 f 127 0b7 Operands: None Operation: Operation: skip if (f<b>) = 0 00h (W) 1Z f Status Affected: None Status Affected: Z Description: If bit 'b' in register 'f' is '1', the next instruction is executed. If bit 'b', in register 'f', is '0', the next instruction is discarded, and a NOP is executed instead, making this a 2TCY instruction. Description: W register is cleared. Zero bit (Z) is set. CALL Call Subroutine CLRWDT Clear Watchdog Timer Syntax: [ label ] CALL k Syntax: [ label ] CLRWDT Operands: 0 k 2047 Operands: None Operation: (PC)+ 1 TOS, k PC<10:0>, (PCLATH<4:3>) PC<12:11> Operation: Status Affected: None 00h WDT 0 WDT prescaler, 1 TO 1 PD Description: Call Subroutine. First, return address (PC+1) is pushed onto the stack. The eleven bit immediate address is loaded into PC bits <10:0>. The upper bits of the PC are loaded from PCLATH. CALL is a two cycle instruction. Status Affected: TO, PD Description: CLRWDT instruction resets the Watchdog Timer. It also resets the prescaler of the WDT. Status bits TO and PD are set. DS41120A-page 144 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 COMF Complement f GOTO Unconditional Branch Syntax: [ label ] COMF Syntax: [ label ] Operands: 0 f 127 d [0,1] Operands: 0 k 2047 Operation: (f) (destination) Operation: k PC<10:0> PCLATH<4:3> PC<12:11> Status Affected: Z Status Affected: None Description: 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'. Description: GOTO is an unconditional branch. The eleven bit immediate value is loaded into PC bits <10:0>. The upper bits of PC are loaded from PCLATH<4:3>. GOTO is a two cycle instruction. DECF Decrement f Syntax: [label] DECF f,d INCF Increment f Operands: 0 f 127 d [0,1] Syntax: [ label ] Operands: 0 f 127 d [0,1] (f) + 1 (destination) f,d GOTO k INCF f,d Operation: (f) - 1 (destination) Status Affected: Z Operation: Description: Decrement register 'f'. If 'd' is 0, the result is stored in the W register. If 'd' is 1, the result is stored back in register 'f'. Status Affected: Z Description: The contents of register 'f' are incremented. If 'd' is 0, the result is placed in the W register. If 'd' is 1, the result is placed back in register 'f'. INCFSZ Increment f, Skip if 0 DECFSZ Decrement f, Skip if 0 Syntax: [ label ] DECFSZ f,d Operands: 0 f 127 d [0,1] Operation: (f) - 1 (destination); skip if result = 0 Status Affected: None Description: The contents of register 'f' are decremented. If 'd' is 0, the result is placed in the W register. If 'd' is 1, the result is placed back in register 'f'. If the result is 1, the next instruction is executed. If the result is 0, then a NOP is executed instead making it a 2TCY instruction. 1999 Microchip Technology Inc. Syntax: [ label ] Operands: 0 f 127 d [0,1] Operation: (f) + 1 (destination), skip if result = 0 Status Affected: None Description: The contents of register 'f' are incremented. If 'd' is 0, the result is placed in the W register. If 'd' is 1, the result is placed back in register 'f'. If the result is 1, the next instruction is executed. If the result is 0, a NOP is executed instead making it a 2TCY instruction. Advanced Information INCFSZ f,d DS41120A-page 145 PIC16C717/770/771 IORLW Inclusive OR Literal with W MOVLW Move Literal to W Syntax: [ label ] Syntax: [ label ] Operands: 0 k 255 Operands: 0 k 255 Operation: (W) .OR. k (W) Operation: k (W) Status Affected: Z Status Affected: None Description: The contents of the W register are OR'ed with the eight bit literal 'k'. The result is placed in the W register. Description: The eight bit literal 'k' is loaded into W register. The don't cares will assemble as 0's. MOVWF Move W to f IORWF Inclusive OR W with f Syntax: [ label ] Syntax: [ label ] Operands: Operands: 0 f 127 d [0,1] 0 f 127 Operation: (W) (f) Operation: (W) .OR. (f) (destination) Status Affected: None Status Affected: Z Description: Move data from W register to register 'f'. Description: Inclusive OR the W register with register 'f'. If 'd' is 0 the result is placed in the W register. If 'd' is 1 the result is placed back in register 'f'. NOP No Operation Syntax: [ label ] Operands: None Operation: No operation Status Affected: None Description: No operation. IORLW k IORWF f,d MOVF Move f Syntax: [ label ] Operands: 0 f 127 d [0,1] Operation: (f) (destination) Status Affected: Z Description: The contents of register f are moved to a destination dependant upon the status of d. If d = 0, destination is W register. If d = 1, the destination is file register f itself. d = 1 is useful to test a file register since status flag Z is affected. DS41120A-page 146 MOVF f,d Advanced Information MOVLW k MOVWF f NOP 1999 Microchip Technology Inc. PIC16C717/770/771 RETFIE Return from Interrupt RLF Rotate Left f through Carry Syntax: [ label ] Syntax: [ label ] Operands: None Operands: Operation: TOS PC, 1 GIE 0 f 127 d [0,1] Operation: See description below None Status Affected: C Description: 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 the W register. If 'd' is 1, the result is stored back in register 'f'. Status Affected: RETFIE RLF C RETLW Return with Literal in W Syntax: [ label ] Operands: Operation: RETLW k f,d Register f RRF Rotate Right f through Carry 0 k 255 Syntax: [ label ] k (W); TOS PC Operands: 0 f 127 d [0,1] Status Affected: None Operation: See description below Description: The W register is loaded with the eight bit literal 'k'. The program counter is loaded from the top of the stack (the return address). This is a two cycle instruction. Status Affected: C Description: 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 the W register. If 'd' is 1, the result is placed back in register 'f'. RRF f,d C Register f RETURN Return from Subroutine Syntax: [ label ] Operands: None SLEEP Operation: TOS PC Syntax: Status Affected: None [ label ] Description: Return from subroutine. The stack is POPed and the top of the stack (TOS) is loaded into the program counter. This is a two cycle instruction. Operands: None Operation: 00h WDT, 0 WDT prescaler, 1 TO, 0 PD Status Affected: TO, PD Description: The power-down status bit, PD is cleared. Time-out status bit, TO is set. Watchdog Timer and its prescaler are cleared. The processor is put into SLEEP mode with the oscillator stopped. See Section 13.8 for more details. RETURN 1999 Microchip Technology Inc. Advanced Information SLEEP DS41120A-page 147 PIC16C717/770/771 SUBLW Syntax: Subtract W from Literal [ label ] SUBLW k Operands: 0 k 255 Operands: 0 k 255 Operation: k - (W) (W) Operation: (W) .XOR. k (W) Status Affected: C, DC, Z Status Affected: Z Description: The W register is subtracted (2's complement method) from the eight bit literal 'k'. The result is placed in the W register. Description: The contents of the W register are XOR'ed with the eight bit literal 'k'. The result is placed in the W register. SUBWF Syntax: Subtract W from f [ label ] SUBWF f,d XORWF Exclusive OR W with f Syntax: [label] Operands: 0 f 127 d [0,1] Operands: 0 f 127 d [0,1] Operation: (f) - (W) (destination) Operation: (W) .XOR. (f) (destination) Status Affected: C, DC, Z Status Affected: Z Description: Description: Exclusive OR the contents of the W register with register 'f'. If 'd' is 0, the result is stored in the W register. If 'd' is 1, the result is stored back in register 'f'. Subtract (2's complement method) W register from register 'f'. If 'd' is 0, the result is stored in the W register. If 'd' is 1, the result is stored back in register 'f'. SWAPF Swap Nibbles in f Syntax: [ label ] SWAPF f,d Operands: 0 f 127 d [0,1] Operation: (f<3:0>) (destination<7:4>), (f<7:4>) (destination<3:0>) Status Affected: None Description: The upper and lower nibbles of register 'f' are exchanged. If 'd' is 0, the result is placed in W register. If 'd' is 1, the result is placed in register 'f'. DS41120A-page 148 XORLW Exclusive OR Literal with W Syntax: [label] Advanced Information XORLW k XORWF f,d 1999 Microchip Technology Inc. PIC16C717/770/771 14.0 DEVELOPMENT SUPPORT (R) The PICmicro microcontrollers are supported with a full range of hardware and software development tools: * Integrated Development Environment - MPLABTM IDE Software * Assemblers/Compilers/Linkers - MPASM Assembler - MPLAB-C17 and MPLAB-C18 C Compilers - MPLINK/MPLIB Linker/Librarian * Simulators - MPLAB-SIM Software Simulator * Emulators - MPLAB-ICE Real-Time In-Circuit Emulator - PICMASTER(R)/PICMASTER-CE In-Circuit Emulator - ICEPICTM * In-Circuit Debugger - MPLAB-ICD for PIC16F877 * Device Programmers - PRO MATE II Universal Programmer - PICSTART Plus Entry-Level Prototype Programmer * Low-Cost Demonstration Boards - SIMICE - PICDEM-1 - PICDEM-2 - PICDEM-3 - PICDEM-17 - SEEVAL - KEELOQ 14.1 MPLAB Integrated Development Environment Software The MPLAB IDE software brings an ease of software development previously unseen in the 8-bit microcontroller market. MPLAB is a Windows-based application which contains: * Multiple functionality - editor - simulator - programmer (sold separately) - emulator (sold separately) * A full featured editor * A project manager * Customizable tool bar and key mapping * A status bar * On-line help 1999 Microchip Technology Inc. MPLAB allows you to: * Edit your source files (either assembly or `C') * One touch assemble (or compile) and download to PICmicro tools (automatically updates all project information) * Debug using: - source files - absolute listing file - object code The ability to use MPLAB with Microchip's simulator, MPLAB-SIM, allows a consistent platform and the ability to easily switch from the cost-effective simulator to the full featured emulator with minimal retraining. 14.2 MPASM Assembler MPASM is a full featured universal macro assembler for all PICmicro MCU's. It can produce absolute code directly in the form of HEX files for device programmers, or it can generate relocatable objects for MPLINK. MPASM has a command line interface and a Windows shell and can be used as a standalone application on a Windows 3.x or greater system. MPASM generates relocatable object files, Intel standard HEX files, MAP files to detail memory usage and symbol reference, an absolute LST file which contains source lines and generated machine code, and a COD file for MPLAB debugging. MPASM features include: * MPASM and MPLINK are integrated into MPLAB projects. * MPASM allows user defined macros to be created for streamlined assembly. * MPASM allows conditional assembly for multi purpose source files. * MPASM directives allow complete control over the assembly process. 14.3 MPLAB-C17 and MPLAB-C18 C Compilers The MPLAB-C17 and MPLAB-C18 Code Development Systems are complete ANSI `C' compilers and integrated development environments for Microchip's PIC17CXXX and PIC18CXXX family of microcontrollers, respectively. These compilers provide powerful integration capabilities and ease of use not found with other compilers. For easier source level debugging, the compilers provide symbol information that is compatible with the MPLAB IDE memory display. Advanced Information DS41120A-page 149 PIC16C717/770/771 14.4 MPLINK/MPLIB Linker/Librarian MPLINK is a relocatable linker for MPASM and MPLAB-C17 and MPLAB-C18. It can link relocatable objects from assembly or C source files along with precompiled libraries using directives from a linker script. MPLIB is a librarian for pre-compiled code to be used with MPLINK. When a routine from a library is called from another source file, only the modules that contains that routine will be linked in with the application. This allows large libraries to be used efficiently in many different applications. MPLIB manages the creation and modification of library files. MPLINK features include: * MPLINK works with MPASM and MPLAB-C17 and MPLAB-C18. * MPLINK allows all memory areas to be defined as sections to provide link-time flexibility. MPLIB features include: * MPLIB makes linking easier because single libraries can be included instead of many smaller files. * MPLIB helps keep code maintainable by grouping related modules together. * MPLIB commands allow libraries to be created and modules to be added, listed, replaced, deleted, or extracted. 14.5 MPLAB-SIM Software Simulator The MPLAB-SIM Software Simulator allows code development in a PC host environment by simulating the PICmicro series microcontrollers on an instruction level. On any given instruction, the data areas can be examined or modified and stimuli can be applied from a file or user-defined key press to any of the pins. The execution can be performed in single step, execute until break, or trace mode. MPLAB-SIM fully supports symbolic debugging using MPLAB-C17 and MPLAB-C18 and MPASM. The Software Simulator offers the flexibility to develop and debug code outside of the laboratory environment making it an excellent multi-project software development tool. 14.6 MPLAB-ICE High Performance Universal In-Circuit Emulator with MPLAB IDE The MPLAB-ICE Universal In-Circuit Emulator is intended to provide the product development engineer with a complete microcontroller design tool set for PICmicro microcontrollers (MCUs). Software control of MPLAB-ICE is provided by the MPLAB Integrated Development Environment (IDE), which allows editing, "make" and download, and source debugging from a single environment. DS41120A-page 150 Interchangeable processor modules allow the system to be easily reconfigured for emulation of different processors. The universal architecture of the MPLAB-ICE allows expansion to support new PICmicro microcontrollers. The MPLAB-ICE Emulator System has been designed as a real-time emulation system with advanced features that are generally found on more expensive development tools. The PC platform and Microsoft(R) Windows 3.x/95/98 environment were chosen to best make these features available to you, the end user. MPLAB-ICE 2000 is a full-featured emulator system with enhanced trace, trigger, and data monitoring features. Both systems use the same processor modules and will operate across the full operating speed range of the PICmicro MCU. 14.7 PICMASTER/PICMASTER CE The PICMASTER system from Microchip Technology is a full-featured, professional quality emulator system. This flexible in-circuit emulator provides a high-quality, universal platform for emulating Microchip 8-bit PICmicro microcontrollers (MCUs). PICMASTER systems are sold worldwide, with a CE compliant model available for European Union (EU) countries. 14.8 ICEPIC ICEPIC is a low-cost in-circuit emulation solution for the Microchip Technology PIC16C5X, PIC16C6X, PIC16C7X, and PIC16CXXX families of 8-bit one-timeprogrammable (OTP) microcontrollers. The modular system can support different subsets of PIC16C5X or PIC16CXXX products through the use of interchangeable personality modules or daughter boards. The emulator is capable of emulating without target application circuitry being present. 14.9 MPLAB-ICD In-Circuit Debugger Microchip's In-Circuit Debugger, MPLAB-ICD, is a powerful, low-cost run-time development tool. This tool is based on the flash PIC16F877 and can be used to develop for this and other PICmicro microcontrollers from the PIC16CXXX family. MPLAB-ICD utilizes the In-Circuit Debugging capability built into the PIC16F87X. This feature, along with Microchip's In-Circuit Serial Programming protocol, offers cost-effective in-circuit flash programming and debugging from the graphical user interface of the MPLAB Integrated Development Environment. This enables a designer to develop and debug source code by watching variables, single-stepping and setting break points. Running at full speed enables testing hardware in real-time. The MPLAB-ICD is also a programmer for the flash PIC16F87X family. Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 14.10 PRO MATE II Universal Programmer The PRO MATE II Universal Programmer is a full-featured programmer capable of operating in stand-alone mode as well as PC-hosted mode. PRO MATE II is CE compliant. The PRO MATE II has programmable VDD and VPP supplies which allows it to verify programmed memory at VDD min and VDD max for maximum reliability. It has an LCD display for instructions and error messages, keys to enter commands and a modular detachable socket assembly to support various package types. In stand-alone mode the PRO MATE II can read, verify or program PICmicro devices. It can also set code-protect bits in this mode. 14.11 PICSTART Plus Entry Level Development System The PICSTART programmer is an easy-to-use, lowcost prototype programmer. It connects to the PC via one of the COM (RS-232) ports. MPLAB Integrated Development Environment software makes using the programmer simple and efficient. PICSTART Plus supports all PICmicro devices with up to 40 pins. Larger pin count devices such as the PIC16C92X, and PIC17C76X may be supported with an adapter socket. PICSTART Plus is CE compliant. 14.12 SIMICE Entry-Level Hardware Simulator SIMICE is an entry-level hardware development system designed to operate in a PC-based environment with Microchip's simulator MPLAB-SIM. Both SIMICE and MPLAB-SIM run under Microchip Technology's MPLAB Integrated Development Environment (IDE) software. Specifically, SIMICE provides hardware simulation for Microchip's PIC12C5XX, PIC12CE5XX, and PIC16C5X families of PICmicro 8-bit microcontrollers. SIMICE works in conjunction with MPLAB-SIM to provide non-real-time I/O port emulation. SIMICE enables a developer to run simulator code for driving the target system. In addition, the target system can provide input to the simulator code. This capability allows for simple and interactive debugging without having to manually generate MPLAB-SIM stimulus files. SIMICE is a valuable debugging tool for entry-level system development. 14.13 PICDEM-1 Low-Cost PICmicro Demonstration Board The PICDEM-1 is a simple board which demonstrates the capabilities of several of Microchip's microcontrollers. The microcontrollers supported are: PIC16C5X (PIC16C54 to PIC16C58A), PIC16C61, PIC16C62X, PIC16C71, PIC16C8X, PIC17C42, PIC17C43 and PIC17C44. All necessary hardware and software is included to run basic demo programs. The users can program the sample microcontrollers provided with 1999 Microchip Technology Inc. the PICDEM-1 board, on a PRO MATE II or PICSTART-Plus programmer, and easily test firmware. The user can also connect the PICDEM-1 board to the MPLAB-ICE emulator and download the firmware to the emulator for testing. Additional prototype area is available for the user to build some additional hardware and connect it to the microcontroller socket(s). Some of the features include an RS-232 interface, a potentiometer for simulated analog input, push-button switches and eight LEDs connected to PORTB. 14.14 PICDEM-2 Low-Cost PIC16CXX Demonstration Board The PICDEM-2 is a simple demonstration board that supports the PIC16C62, PIC16C64, PIC16C65, PIC16C73 and PIC16C74 microcontrollers. All the necessary hardware and software is included to run the basic demonstration programs. The user can program the sample microcontrollers provided with the PICDEM-2 board, on a PRO MATE II programmer or PICSTART-Plus, and easily test firmware. The MPLAB-ICE emulator may also be used with the PICDEM-2 board to test firmware. Additional prototype area has been provided to the user for adding additional hardware and connecting it to the microcontroller socket(s). Some of the features include a RS-232 interface, push-button switches, a potentiometer for simulated analog input, a Serial EEPROM to demonstrate usage of the I2C bus and separate headers for connection to an LCD module and a keypad. 14.15 PICDEM-3 Low-Cost PIC16CXXX Demonstration Board The PICDEM-3 is a simple demonstration board that supports the PIC16C923 and PIC16C924 in the PLCC package. It will also support future 44-pin PLCC microcontrollers with a LCD Module. All the necessary hardware and software is included to run the basic demonstration programs. The user can program the sample microcontrollers provided with the PICDEM-3 board, on a PRO MATE II programmer or PICSTART Plus with an adapter socket, and easily test firmware. The MPLAB-ICE emulator may also be used with the PICDEM-3 board to test firmware. Additional prototype area has been provided to the user for adding hardware and connecting it to the microcontroller socket(s). Some of the features include an RS-232 interface, push-button switches, a potentiometer for simulated analog input, a thermistor and separate headers for connection to an external LCD module and a keypad. Also provided on the PICDEM-3 board is an LCD panel, with 4 commons and 12 segments, that is capable of displaying time, temperature and day of the week. The PICDEM-3 provides an additional RS-232 interface and Windows 3.1 software for showing the demultiplexed LCD signals on a PC. A simple serial interface allows the user to construct a hardware demultiplexer for the LCD signals. Advanced Information DS41120A-page 151 PIC16C717/770/771 14.16 PICDEM-17 The PICDEM-17 is an evaluation board that demonstrates the capabilities of several Microchip microcontrollers, including PIC17C752, PIC17C756, PIC17C762, and PIC17C766. All necessary hardware is included to run basic demo programs, which are supplied on a 3.5-inch disk. A programmed sample is included, and the user may erase it and program it with the other sample programs using the PRO MATE II or PICSTART Plus device programmers and easily debug and test the sample code. In addition, PICDEM-17 supports down-loading of programs to and executing out of external FLASH memory on board. The PICDEM-17 is also usable with the MPLAB-ICE or PICMASTER emulator, and all of the sample programs can be run and modified using either emulator. Additionally, a generous prototype area is available for user hardware. 14.17 SEEVAL Evaluation and Programming System The SEEVAL SEEPROM Designer's Kit supports all Microchip 2-wire and 3-wire Serial EEPROMs. The kit includes everything necessary to read, write, erase or program special features of any Microchip SEEPROM product including Smart Serials and secure serials. The Total Endurance Disk is included to aid in tradeoff analysis and reliability calculations. The total kit can significantly reduce time-to-market and result in an optimized system. 14.18 KEELOQ Evaluation and Programming Tools KEELOQ evaluation and programming tools support Microchips HCS Secure Data Products. The HCS evaluation kit includes an LCD display to show changing codes, a decoder to decode transmissions, and a programming interface to program test transmitters. DS41120A-page 152 Advanced Information 1999 Microchip Technology Inc. Software Tools Emulators 1999 Microchip Technology Inc. Programmers Debugger a PIC17C4X a a a a a a a PIC16C9XX a a a a a a a PIC16F8XX a a a a a PIC16C8X a a a a a a a PIC16C7XX a a a a a a a PIC16C7X a a a a a a a PIC16F62X a a a PIC16CXXX a a a a a PIC16C6X a a a a a a a PIC16C5X a a a a a a a PIC14000 a a a a a a PIC12CXXX a a a a a a a Advanced Information a a a a a a a a a a a a a a a a a * Contact the Microchip Technology Inc. web site at www.microchip.com for information on how to use the MPLAB-ICD In-Circuit Debugger (DV164001) with PIC16C62, 63, 64, 65, 72, 73, 74, 76, 77 ** Contact Microchip Technology Inc. for availability date. Development tool is available on select devices. MCP2510 CAN Developer's Kit MCRFXXX a a a 13.56 MHz Anticollision microID Developer's Kit 125 kHz Anticollision microID Developer's Kit 125 kHz microID Developer's Kit microIDTM Programmer's Kit KEELOQ Transponder Kit KEELOQ(R) Evaluation Kit PICDEM-17 a PICDEM-14A a PICDEM-3 a a a a PICDEM-2 a 24CXX/ 25CXX/ 93CXX a a PICDEM-1 a a a ** ** HCSXXX a SIMICE MPLAB-ICD In-Circuit Debugger ICEPIC Low-Cost In-Circuit Emulator PICMASTER/PICMASTER-CE MPLABTM-ICE MPASM/MPLINK MPLAB C18 Compiler * a PRO MATE II Universal Programmer a PICSTARTPlus Low-Cost Universal Dev. Kit a a a * PIC17C7XX a a ** PIC18CXX2 a a MPLAB C17 Compiler TABLE 14-1: Demo Boards and Eval Kits MPLAB Integrated Development Environment PIC16C717/770/771 DEVELOPMENT TOOLS FROM MICROCHIP MCP2510 a DS41120A-page 153 PIC16C717/770/771 NOTES: DS41120A-page 154 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 15.0 ELECTRICAL CHARACTERISTICS Absolute Maximum Ratings Ambient temperature under bias................................................................................................................ .-55 to +125C Storage temperature .............................................................................................................................. -65C to +150C Voltage on any pin with respect to VSS (except VDD, MCLR and RA4)........................................... -0.3V to (VDD + 0.3V) Voltage on VDD with respect to VSS ............................................................................................................ -0.3 to +7.5V Maximum voltage between AVDD and VDD pins................................................................................................................. 0.3V Maximum voltage between AVSS and VSS pins ................................................................................................................. 0.3V Voltage on MCLR with respect to VSS........................................................................................................ -0.3V to +8.5V Voltage on RA4 with respect to Vss ......................................................................................................... -0.3V to +10.5V Total power dissipation (Note 1)................................................................................................................................1.0W Maximum current out of VSS pin ...........................................................................................................................300 mA Maximum current into VDD pin ..............................................................................................................................250 mA Input clamp current, IIK (VI < 0 or VI > VDD)..................................................................................................................... 20 mA Output clamp current, IOK (VO < 0 or VO > VDD) ............................................................................................................. 20 mA Maximum output current sunk by any I/O pin..........................................................................................................25 mA Maximum output current sourced by any I/O pin ....................................................................................................25 mA Maximum current sunk by PORTA and PORTB (combined) .................................................................................200 mA Maximum current sourced by PORTA and PORTB (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. 1999 Microchip Technology Inc. Advanced Information DS41120A-page 155 PIC16C717/770/771 FIGURE 15-1: PIC16C717/770/771 VOLTAGE-FREQUENCY GRAPH, -40C TA +85C 6.0 5.5 5.0 VDD (Volts) 4.5 4.0 3.5 3.0 2.5 0 4 10 20 25 Frequency (MHz) Note 1: The shaded region indicates the permissible combinations of voltage and frequency. FIGURE 15-2: PIC16LC717/770/771 VOLTAGE-FREQUENCY GRAPH, 0C TA +70C 6.0 5.5 5.0 VDD (Volts) 4.5 4.0 3.5 3.0 2.5 0 4 10 20 25 Frequency (MHz) Note 1: The shaded region indicates the permissible combinations of voltage and frequency. DS41120A-page 156 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 FIGURE 15-3: PIC16LC717/770/771 VOLTAGE-FREQUENCY GRAPH, -40C TA 0C, +70C TA +85C 6.0 5.5 5.0 VDD (Volts) 4.5 4.0 3.5 3.0 2.5 0 4 10 20 25 Frequency (MHz) Note 1: The shaded region indicates the permissible combinations of voltage and frequency. 1999 Microchip Technology Inc. Advanced Information DS41120A-page 157 PIC16C717/770/771 15.1 DC Characteristics: PIC16C717/770/771 (Commercial, Industrial) Standard Operating Conditions (unless otherwise stated) Operating temperature -40C TA +85C for industrial and 0C TA +70C for commercial DC CHARACTERISTICS Param No. Sym Characteristic Min Typ Max Units Conditions D001 VDD Supply Voltage 4.0 -- 5.5 V D002* VDR RAM Data Retention -- 1.5 -- V -- VSS -- V See section on Power-on Reset for details 0.05 -- -- V/ms See section on Power-on Reset for details. PWRT enabled TBD mA FOSC = 20 MHz, VDD = 5.5V* TBD mA FOSC = 20 MHz, VDD = 4.0V TBD mA FOSC = 4 MHz, VDD = 4.0V* TBD mA FOSC = 32 KHz, VDD = 4.0V TBD 16 19 mA A A VDD = 5.5V, 0C to +70C* VDD = 4.0V, 0C to +70C VDD = 4.0V, -40C to +85C Voltage(1) D003 VPOR VDD start voltage to ensure internal Power-on Reset signal D004* SVDD VDD rise rate to ensure internal Poweron Reset signal D010 IDD Supply Current(2) D020 D020A IPD Power-down Current -- -- -- (3) 1.5 1.5 Module Differential Current(5) D021 IWDT Watchdog Timer -- 6.0 20 A VDD = 4.0V D023B* IBG(6) Bandgap voltage generator -- 40A TBD A VDD = 4.0V D025* IT1OSC Timer1 oscillator -- 5 9 A VDD = 4.0V D026* IAD A/D Converter -- 300 -- A VDD = 5.5V, A/D on, not converting ILVD Low Voltage Detect 10 TBD A VDD = 4.0V* IPBOR Programmable Brown-Out Reset 10 TBD A PBOR enabled, VDD = 5.0V* IVRH Voltage Reference High 70 TBD A VDD = 5.0V, no load on VRH* 70 TBD A VDD = 4.0V, no load on VRL* -- 4 37 -- 37 -- -- 200 -- -- TBD -- 4 20 KHz MHz MHz MHz MHz MHz MHz All temperatures All temperatures, OSCF = 1 All temperatures, OSCF = 0 All temperatures, OSCF = 1 All temperatures, OSCF = 0 All temperatures All temperatures 1A IVRL Voltage Reference Low Fosc LP oscillator, operating freq. INTRC oscillator operating freq. ER oscillator operating freq. XT oscillator operating freq. HS oscillator operating freq. * Note 1: 2: 3: 4: 5: 6: 9 -- -- TBD -- 0 0 These parameters are characterized but not tested. Data in "Typ" column is at 5V, 25C unless otherwise stated. These parameters are for design guidance only and are not tested. This is the limit to which VDD can be lowered without losing RAM data. The supply current is mainly a function of the operating voltage and frequency. Other factors such as I/O pin loading and switching rate, oscillator type, 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 tristated, pulled to VDD MCLR = VDD; WDT enabled/disabled as specified. 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 hi-impedance state and tied to VDD or VSS. For ER osc configuration, current through Rext is not included. The current through the resistor can be estimated by the formula Ir = TBD with Rext in kOhm. The current is the additional current consumed when the peripheral is enabled. This current should be added to the base (IPD or IDD) current. The bandgap voltage reference provides 1.22V nominal to the VRL, VRH, LVD and BOR circuits. When calculating current consumption use the following formula: IVRL + IVRH + ILVD + IBOR + IBG. Any of the IVRL, IVRH, ILVD or IBOR can be 0. DS41120A-page 158 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 15.2 DC Characteristics: PIC16LC717/770/771 (Commercial, Industrial) Standard Operating Conditions (unless otherwise stated) Operating temperature -40C TA +85C for industrial and 0C TA +70C for commercial DC CHARACTERISTICS Param No. Sym D001 VDD Characteristic Supply Voltage Min Typ Max Units 2.5 -- 5.5 V Conditions D002* VDR RAM Data Retention Voltage -- 1.5 -- V D003 VPOR VDD start voltage to ensure internal Power-on Reset signal -- VSS -- V See section on Power-on Reset for details D004* SVDD VDD rise rate to ensure internal Power-on Reset signal 0.05 -- -- V/ms See section on Power-on Reset for details. PWRT enabled D010 Supply IDD TBD mA FOSC = 20 MHz, VDD = 5.5V* TBD TBD TBD mA mA mA FOSC = 20 MHz, VDD = 4.0V FOSC = 10 MHz, VDD = 3.0V FOSC = 4 MHz, VDD = 2.5V (1) Current(2) D020 D020A IPD Power-down Current(3) TBD mA FOSC = 32 KHz, VDD = 2.5V -- -- -- -- -- TBD 1.5 1.5 0.9 0.9 TBD 16 19 5 5 A A A A A VDD = 5.5V, 0C to +70C VDD = 4.0V, 0C to +70C VDD = 4.0V, -40C to +85C VDD = 2.5V, 0C to +70C VDD = 3.0V, -40C to +85C -- -- 6 40 20 TBD A A VDD = 3.0V VDD = 3.0V Module Differential Current(5) D021 IWDT D023B* IBG Watchdog Timer Bandgap voltage generator D025* IT1OSC Timer1 oscillator -- 1.5 3 A VDD = 3.0V D026* IAD A/D Converter -- 300 -- A VDD = 5.5V, A/D on, not converting ILVD Low Voltage Detect 10 TBD A VDD = 4.0V* IPBOR Programmable Brown-Out Reset 10 TBD A PBOR enabled, VDD = 5.0V* IVRH Voltage Reference High 70 TBD A VDD = 5.0V, no load on VRH* 70 TBD A VDD = 4.0V, no load on VRL* -- 4 37 -- 37 -- -- 200 -- -- TBD -- 4 20 KHz MHz MHz MHz MHz MHz MHz All temperatures All temperatures, OSCF = 1 All temperatures, OSCF = 0 All temperatures, OSCF = 1 All temperatures, OSCF = 0 All temperatures All temperatures 1A IVRL Voltage Reference Low Fosc LP oscillator, operating freq. INTRC oscillator operating freq. ER oscillator operating freq. XT oscillator operating freq. HS oscillator operating freq. * Note 1: 2: 3: 4: 5: 9 -- -- TBD -- 0 0 These parameters are characterized but not tested. Data in "Typ" column is at 5V, 25C unless otherwise stated. These parameters are for design guidance only and are not tested. This is the limit to which VDD can be lowered without losing RAM data. The supply current is mainly a function of the operating voltage and frequency. Other factors such as I/O pin loading and switching rate, oscillator type, 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 tristated, pulled to VDD MCLR = VDD; WDT enabled/disabled as specified. 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 hi-impedance state and tied to VDD or VSS. For ER osc configuration, current through Rext is not included. The current through the resistor can be estimated by the formula Ir = VDD/2Rext (mA) with Rext in kOhm. The current is the additional current consumed when the peripheral is enabled. This current should be added to the base (IPD or IDD) current. 1999 Microchip Technology Inc. Advanced Information DS41120A-page 159 PIC16C717/770/771 15.3 DC Characteristics: PIC16C717/770/771 & PIC16LC717/770/771 (Commercial, Industrial) Standard Operating Conditions (unless otherwise stated) Operating temperature -40C TA +85C for industrial and 0C TA +70C for commercial Operating voltage VDD range as described in DC spec Section 15.1 and Section 15.2. DC CHARACTERISTICS Param No. Sym VIL D030 D030A D031 D032 Characteristic Input Low Voltage I/O ports with TTL buffer with Schmitt Trigger buffer D033 VIH MCLR OSC1 (in XT, HS, LP and EC) Input High Voltage I/O ports with TTL buffer D040 D040A D041 D042 D042A D070 with Schmitt Trigger buffer MCLR OSC1 (XT, HS, LP and EC) IPURB PORTB weak pull-up current per pin Min Typ Max Units VSS VSS VSS VSS -- -- -- -- 0.15VDD 0.8V 0.2VDD 0.2VDD V V V V VSS -- 0.3VDD V Conditions For entire VDD range 4.5V VDD 5.5V For entire VDD range -- 2.0 (0.25VDD + 0.8V) 0.8VDD 0.8VDD 0.7VDD 50 -- -- VDD VDD V V 4.5V VDD 5.5V For entire VDD range -- -- -- 250 VDD VDD VDD 400 V V V A For entire VDD range -- -- 1 A Vss VPIN VDD, Pin at hi-impedance Vss VPIN VDD, Pin at hi-impedance Vss VPIN VDD Vss VPIN VDD, XT, HS, LP and EC osc configuration VDD = 5V, VPIN = VSS D060 IIL Input Leakage Current (1,2) I/O ports (with digital functions) D060A IIL I/O ports (with analog functions) -- -- 100 nA RA5/MCLR/VPP OSC1 -- -- -- -- 5 5 A A Output Low Voltage I/O ports Output High Voltage -- -- 0.6 V IOL = 8.5 mA, VDD = 4.5V -- -- V IOH = -3.0 mA, VDD = 4.5V -- 10.5 V RA4 pin -- 15 pF In XT, HS and LP modes when external clock is used to drive OSC1. D061 D063 D080 D090 D150* D100 VOL VDD - 0.7 I/O ports(2) -- VOD Open-Drain High Voltage Capacitive Loading Specs on Output Pins* COSC2 OSC2 pin -- VOH -- -- 50 pF -- -- 400 pF SCL, SDA in I2C mode -- -- 200 pF VRH output enabled CVRH VRH pin -- -- 200 pF VRL output enabled CVRL VRL pin * These parameters are characterized but not tested. Data in "Typ" column is at 5V, 25C unless otherwise stated. These parameters are for design guidance only and are not tested. Note 1: The leakage current on the MCLR pin is strongly dependent on the applied voltage level. The specified levels represent normal operating conditions. Higher leakage current may be measured at different input voltages. 2: Negative current is defined as current sourced by the pin. D101 D102 CIO CB All I/O pins and OSC2 (in RC mode) DS41120A-page 160 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 15.4 AC Characteristics: PIC16C717/770/771 & PIC16LC717/770/771 (Commercial, Industrial) 15.4.1 TIMING PARAMETER SYMBOLOGY The timing parameter symbols have been created following one of the following formats: 1. TppS2ppS 3. TCC:ST (I2C specifications only) 2. TppS 4. Ts (I2C specifications only) T F Frequency Lowercase letters (pp) and their meanings: pp cc CCP1 ck CLKOUT cs CS di SDI do SDO dt Data in io I/O port mc MCLR Uppercase letters and their meanings: S F Fall H High I Invalid (Hi-impedance) L Low I2C only AA BUF output access Bus free TCC:ST (I2C specifications only) CC HD Hold ST DAT DATA input hold STA START condition T Time osc rd rw sc ss t0 t1 wr OSC1 RD RD or WR SCK SS T0CKI T1CKI WR P R V Z Period Rise Valid Hi-impedance High Low High Low SU Setup STO STOP condition FIGURE 15-4: LOAD CONDITIONS Load condition 1 Load condition 2 VDD/2 RL CL Pin CL Pin VSS VSS RL = 464 CL = 50 pF 15 pF 1999 Microchip Technology Inc. for all pins except OSC2 for OSC2 output Advanced Information DS41120A-page 161 PIC16C717/770/771 15.4.2 TIMING DIAGRAMS AND SPECIFICATIONS FIGURE 15-5: CLKOUT AND I/O TIMING Q1 Q4 Q2 Q3 OSC1 11 10 CLKOUT 13 14 19 12 18 16 I/O Pin (input) 15 17 I/O Pin (output) new value old value 20, 21 Note: Refer to Figure 15-4 for load conditions. TABLE 15-1: Parameter No. CLKOUT AND I/O TIMING REQUIREMENTS Sym Characteristic Min Typ Max Units Conditions 10* TosH2ckL OSC1 to CLKOUT -- 75 200 ns Note 1 11* TosH2ckH OSC1 to CLKOUT -- 75 200 ns Note 1 12* TckR CLKOUT rise time -- 35 100 ns Note 1 13* TckF CLKOUT fall time -- 35 100 ns Note 1 14* TckL2ioV CLKOUT to Port out valid -- -- 0.5TCY + 20 ns Note 1 15* TioV2ckH Port in valid before CLKOUT 0.25TCY + 25 -- -- ns Note 1 16* TckH2ioI Port in hold after CLKOUT 0 -- -- ns Note 1 17* TosH2ioV OSC1 (Q1 cycle) to Port out valid -- 50 150 ns 18* TosH2ioI PIC16C717/770/771 OSC1 (Q2 cycle) to Port input invalid (I/O in PIC16LC717/770/771 hold time) 100 -- -- ns 200 -- -- ns 19* TioV2osH Port input valid to OSC1 (I/O in setup time) 0 -- -- ns 20* TioR Port output rise time PIC16C717/770/771 -- 10 25 ns PIC16LC717/770/771 -- -- 60 ns 21* TioF Port output fall time PIC16C717/770/771 -- 10 25 ns PIC16LC717/770/771 22* 23* -- -- 60 ns Tinp INT pin high or low time TCY -- -- ns Trbp RB7:RB0 change INT high or low time TCY -- -- ns * These parameters are characterized but not tested. Data in "Typ" column is at 5V, 25C unless otherwise stated. These parameters are for design guidance only and are not tested. These parameters are asynchronous events not related to any internal clock edges. Note 1: Measurements are taken in RC Mode where CLKOUT output is 4 x TOSC. DS41120A-page 162 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 FIGURE 15-6: EXTERNAL CLOCK TIMING Q4 Q1 Q2 Q3 Q4 Q1 OSC1 1 3 4 3 4 2 CLKOUT TABLE 15-2: Parameter No. 1A Sym FOSC 1 EXTERNAL CLOCK TIMING REQUIREMENTS TOSC Characteristic Min Typ Max Units Conditions External CLKIN Frequency (Note 1) DC -- 4 MHz XT osc mode DC -- 20 MHz EC osc mode HS osc mode DC -- 20 MHz DC -- 200 kHz LP osc mode Oscillator Frequency (Note 1) 0.1 -- 4 MHz XT osc mode 4 5 -- -- 20 200 MHz kHz HS osc mode LP osc mode External CLKIN Period (Note 1) 250 -- -- ns XT and RC osc mode 50 -- -- ns EC osc mode 50 -- -- ns HS osc mode 5 -- -- s LP osc mode 250 -- 10,000 ns XT osc mode 50 -- 250 ns HS osc mode 5 -- -- s LP osc mode ns TCY = 4/FOSC XT oscillator Oscillator Period (Note 1) 2 TCY Instruction Cycle Time (Note 1) 200 TCY DC 3* TosL, TosH External Clock in (OSC1) High or Low Time 100 -- -- ns 2.5 -- -- s LP oscillator 15 -- -- ns HS oscillator -- -- 25 ns XT oscillator -- -- 50 ns LP oscillator -- -- 15 ns HS oscillator EC oscillator 4* TosR, TosF External Clock in (OSC1) Rise or Fall Time EC oscillator * These parameters are characterized but not tested. Data in "Typ" column is at 5V, 25C unless otherwise stated. These parameters are for design guidance only and are not tested. Note 1: Instruction cycle period (TCY) equals four times the input oscillator time-base period. All specified values are based on characterization data for that particular oscillator type under standard operating conditions with the device executing code. Exceeding these specified limits may result in an unstable oscillator operation and/or higher than expected current consumption. All devices are tested to operate at "min." values with an external clock applied to the OSC1/CLKIN pin. When an external clock input is used, the "Max." cycle time limit is "DC" (no clock) for all devices. 1999 Microchip Technology Inc. Advanced Information DS41120A-page 163 PIC16C717/770/771 TABLE 15-3: CALIBRATED INTERNAL RC FREQUENCIES - PIC16C717/770/771 AND PIC16LC717/770/771 AC Characteristics Parameter No. Standard Operating Conditions (unless otherwise specified) Operating Temperature 0C TA +70C (commercial), -40C TA +85C (industrial), Operating Voltage VDD range is described in Section 15.1 and Section 15.2 Min* Typ(1) Internal Calibrated RC Frequency 3.65 4.00 4.28 MHz VDD = 5.0V Internal Calibrated RC Frequency 3.55 4.00 4.31 MHz VDD = 2.5V Sym Characteristic Max* Units Conditions * These parameters are characterized but not tested. Note 1: Data in the Typical ("Typ") column is at 5V, 25C unless otherwise stated. These parameters are for design guidance only and are not tested. FIGURE 15-7: RESET, WATCHDOG TIMER, OSCILLATOR START-UP TIMER AND POWER-UP TIMER TIMING VDD MCLR 30 Internal POR 33 PWRT Time-out 32 OSC Time-out Internal RESET Watchdog Timer RESET 31 34 34 I/O Pins Note: Refer to Figure 15-4 for load conditions. FIGURE 15-8: BROWN-OUT RESET TIMING VDD BVDD 35 DS41120A-page 164 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 TABLE 15-4: Parameter No. RESET, WATCHDOG TIMER, OSCILLATOR START-UP TIMER, POWER-UP TIMER, AND BROWN-OUT RESET REQUIREMENTS Sym Characteristic Min Typ Max Units Conditions 30* TMCL MCLR Pulse Width (low) 2 -- -- s VDD = 5V, -40C to +85C 31* TWDT Watchdog Timer Time-out Period (No Prescaler) 7 18 33 ms VDD = 5V, -40C to +85C 32* TOST Oscillation Start-up Timer Period -- 1024 TOSC -- -- TOSC = OSC1 period 33* TPWRT Power up Timer Period 28 72 132 ms VDD = 5V, -40C to +85C 34* TIOZ I/O Hi-impedance from MCLR Low or Watchdog Timer Reset -- -- 2.1 s TBOR Brown-out Reset pulse width 100 -- -- s 35* * VDD VBOR (D005) These parameters are characterized but not tested. Data in "Typ" column is at 5V, 25C unless otherwise stated. These parameters are for design guidance only and are not tested. FIGURE 15-9: BROWN-OUT RESET CHARACTERISTICS VDD VBOR (device not in Brown-out Reset) (device in Brown-out Reset) RESET (due to BOR) 72 ms time out FIGURE 15-10: TIMER0 AND TIMER1 EXTERNAL CLOCK TIMINGS RA4/T0CKI 41 40 42 RC0/T1OSO/T1CKI 46 45 47 48 TMR0 or TMR1 Note: Refer to Figure 15-4 for load conditions. 1999 Microchip Technology Inc. Advanced Information DS41120A-page 165 PIC16C717/770/771 TABLE 15-5: Param No. 40* 41* 42* 45* 46* 47* 48 * Sym Tt0H TIMER0 AND TIMER1 EXTERNAL CLOCK REQUIREMENTS Characteristic T0CKI High Pulse Width No Prescaler With Prescaler No Prescaler With Prescaler Min Typ Max 0.5TCY + 20 -- -- ns 10 -- -- -- -- -- -- -- -- -- -- ns ns ns ns ns -- -- -- -- -- -- ns ns ns -- -- -- -- -- -- -- -- -- -- ns ns ns ns ns -- -- -- -- -- -- ns ns ns -- -- ns -- -- -- -- -- 50 ns ns kHz -- 7Tosc -- 0.5TCY + 20 10 TCY + 40 Tt0P T0CKI Period No Prescaler Greater of: With Prescaler 20 or TCY + 40 N Tt1H T1CKI High Time Synchronous, Prescaler = 1 0.5TCY + 20 Synchronous, PIC16C717/770/771 15 Prescaler = PIC16LC717/770/771 25 2,4,8 Asynchronous PIC16C717/770/771 30 PIC16LC717/770/771 50 Tt1L T1CKI Low Time Synchronous, Prescaler = 1 0.5TCY + 20 Synchronous, PIC16C717/770/771 15 Prescaler = PIC16LC717/770/771 25 2,4,8 Asynchronous PIC16C717/770/771 30 PIC16LC717/770/771 50 Tt1P T1CKI input period Synchronous PIC16C717/770/771 Greater of: 30 OR TCY + 40 N PIC16LC717/770/771 Greater of: 50 OR TCY + 40 N Asynchronous PIC16C717/770/771 60 PIC16LC717/770/771 100 Ft1 Timer1 oscillator input frequency range DC (oscillator enabled by setting bit T1OSCEN) Tcke2tmr1 Delay from external clock edge to timer increment 2Tosc Tt0L T0CKI Low Pulse Width Units Conditions Must also meet parameter 42 Must also meet parameter 42 N = prescale value (2, 4, ..., 256) Must also meet parameter 47 Must also meet parameter 47 N = prescale value (1, 2, 4, 8) N = prescale value (1, 2, 4, 8) These parameters are characterized but not tested. Data in "Typ" column is at 5V, 25C unless otherwise stated. These parameters are for design guidance only and are not tested. FIGURE 15-11: ENHANCED CAPTURE/COMPARE/PWM TIMINGS (ECCP1) RB3/CCP1/P1A (Capture Mode) 50 51 52 RB3/CCP1/P1A (Compare or PWM Mode) 53 54 Note: Refer to Figure 15-4 for load conditions. DS41120A-page 166 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 TABLE 15-6: Param No. 50* ENHANCED CAPTURE/COMPARE/PWM REQUIREMENTS (ECCP1) Sym Characteristic TccL CCP1 input low time Min No Prescaler PIC16C717/770/771 With Prescaler PIC16LC717/770/771 51* TccH CCP1 input high time TccR CCP1 output fall time 54* * TccF CCP1 output fall time -- ns 10 -- -- ns -- -- ns -- -- ns 10 -- -- ns 20 -- -- ns 3TCY + 40 N -- -- ns PIC16C717/770/771 -- 10 25 ns PIC16LC717/770/771 -- 25 45 ns PIC16C717/770/771 -- 10 25 ns PIC16LC717/770/771 -- 25 45 ns PIC16C717/770/771 53* -- 20 With Prescaler PIC16LC717/770/771 TccP CCP1 input period 0.5TCY + 20 0.5TCY + 20 No Prescaler 52* Typ Max Units Conditions N = prescale value (1,4 or 16) These parameters are characterized but not tested. Data in "Typ" column is at 5V, 25C unless otherwise stated. These parameters are for design guidance only and are not tested. 1999 Microchip Technology Inc. Advanced Information DS41120A-page 167 PIC16C717/770/771 15.5 Analog Peripherals Characteristics: PIC16C717/770/771 & PIC16LC717/ 770/771 (Commercial, Industrial) 15.5.1 BANDGAP MODULE FIGURE 15-12: BANDGAP START-UP TIME VBGAP = 1.2V (internal use only) VBGAP Enable Bandgap TBGAP Bandgap stable TABLE 15-7: Parameter No. 36* * BANDGAP START-UP TIME Sym TBGAP Characteristic Bandgap start-up time Min Typ Max Units Conditions -- 30 TBD S Defined as the time between the instant that the bandgap is enabled and the moment that the bandgap reference voltage is stable. These parameters are characterized but not tested. Data in "Typ" column is at 5V, 25C unless otherwise stated. These parameters are for design guidance only and are not tested. DS41120A-page 168 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 15.5.2 LOW VOLTAGE DETECT MODULE (LVD) TABLE 15-8: LOW-VOLTAGE DETECT CHARACTERISTICS VDD VLVD (LVDIF set by hardware) LVDIF (LVDIF can be cleared in software anytime during the gray area) TABLE 15-9: ELECTRICAL CHARACTERISTICS: LVD DC CHARACTERISTICS Param No. D420* D422* D423* * Note 1: Standard Operating Conditions (unless otherwise stated) Operating temperature -40C TA +85C for industrial and 0C TA +70C for commercial Operating voltage VDD range as described in DC spec Section 15.1 and Section 15.2. Characteristic Symbol LVV = 0100 LVV = 0101 LVV = 0110 LVV = 0111 LVV = 1000 LVV = 1001 LVV = 1010 LVV = 1011 LVV = 1100 LVV = 1101 LVV = 1110 LVD Voltage Temperature coefficient LVD Voltage Supply Regulation Min Typ Max Units 2.5 2.7 2.8 3.0 3.3 3.5 3.6 3.8 4.0 4.2 4.5 2.66 2.86 2.98 3.2 3.52 3.72 3.84 4.04 4.26 4.46 4.78 50 V V V V V V V V V V V ppm/C 50 V/V TCVOUT -- 2.58 2.78 2.89 3.1 3.41 3.61 3.72 3.92 4.13 4.33 4.64 15 VLVD/ VDD -- -- LVD Voltage Conditions These parameters are characterized but not tested. Production tested at Tamb = 25C. Specifications over temperature limits ensured by characterization. 1999 Microchip Technology Inc. Advanced Information DS41120A-page 169 PIC16C717/770/771 15.5.3 PROGRAMMABLE BROWN-OUT RESET MODULE (PBOR) TABLE 15-10: DC CHARACTERISTICS: PBOR DC CHARACTERISTICS Param No. Standard Operating Conditions (unless otherwise stated) Operating temperature -40C TA +85C for industrial and 0C TA +70C for commercial Operating voltage VDD range as described in DC spec Section 15.1 and Section 15.2. Characteristic D005* Symbol BOR Voltage BORV<1:0> = 11 BORV<1:0> = 10 BORV<1:0> = 01 BORV<1:0> = 00 D006* BOR Voltage Temperature coefficient D006A* BOR Voltage Supply Regulation * 15.5.4 VBOR Min Typ Max 2.5 2.58 2.66 2.7 4.2 4.5 -- 2.78 4.33 4.64 15 -- -- 2.86 4.46 4.78 50 50 TCVOUT VBOR/ VDD Units Conditions V ppm/C V/V These parameters are characterized but not tested. VREF MODULE TABLE 15-11: DC CHARACTERISTICS: VREF Standard Operating Conditions (unless otherwise stated) Operating temperature -40C TA +85C for industrial and 0C TA +70C for commercial Operating voltage VDD range as described in DC spec Section 15.1 and Section 15.2. DC CHARACTERISTICS Param No. D400 D402* D404* D405* * D406* D407* * Symbol VRL VRH TCVOUT IVREFSO IVREFSI CL VOUT/ IOUT VOUT/ VDD Characteristic Min Typ Max Units Output Voltage 2.0 4.0 Output Voltage Temperature coefficient External Load Source External Load Sink External capacitor load Load Regulation -- 2.048 4.096 15 2.1 4.2 50 V V ppm/C -- -- -- -- -- -- mA mA pF -- -- 1 1 5 -5 200 TBD TBD -- -- 50 Supply Regulation Conditions mV/mA VDD 2.5V VDD 4.5V Isource = 0 mA to 5 mA Isink = 0 mA to 5 mA V/V These parameters are characterized but not tested. Data in "Typ" column is at 5V, 25C unless otherwise stated. These parameters are for design guidance only and are not tested. DS41120A-page 170 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 15.5.5 A/D CONVERTER MODULE TABLE 15-12: PIC16C770/771 AND PIC16LC770/771 A/D CONVERTER CHARACTERISTICS: Param No. Sym Characteristic Min Typ Max Units Conditions A01 NR Resolution -- -- 12 bits bit Min. resolution for A/D is 1 mV, VREF+ = AVDD = 4.096V, VREF- = AVSS = 0V, VREF- VAIN VREF+ A03 EIL Integral error -- -- TBD -- VREF+ = AVDD = 4.096V, VREF- = AVSS = 0V, VREF- VAIN VREF+ A04 EDL Differential error -- -- TBD -- No missing codes to 10 bits VREF+ = AVDD = 4.096V, VREF- = AVSS = 0V, VREF- VAIN VREF+ A06 EOFF Offset error -- -- TBD -- VREF+ = AVDD = 4.096V, VREF- = AVSS = 0V, VREF- VAIN VREF+ A07 EGN Gain Error -- -- TBD LSb VREF+ = AVDD = 4.096V, VREF- = AVSS = 0V, VREF- VAIN VREF+ A10 -- Monotonicity -- guaranteed(3) -- -- AVSS VAIN VREF+ A20 VREF Reference voltage (VREF+ VREF-) 4.096 -- VDD +0.3V V Absolute minimum electrical spec to ensure 12-bit accuracy. A21 VREF+ Reference V High (AVDD or VREF+) VREF- -- AVDD V Min. resolution for A/D is 1 mV A22 VREF- Reference V Low (AVSS or VREF-) AVSS -- VREF+ V Min. resolution for A/D is 1 mV A25 VAIN Analog input voltage VREFL -- VREFH V A30 ZAIN Recommended impedance of analog voltage source -- -- 2.5 k A50 IREF VREF input current (Note 2) -- -- 10 A During VAIN acquisition. Based on differential of VHOLD to VAIN. To charge CHOLD see Section 11.0. During A/D conversion cycle. * These parameters are characterized but not tested. Data in "Typ" column is at 5V, 25C unless otherwise stated. These parameters are for design guidance only and are not tested. Note 1: When A/D is off, it will not consume any current other than minor leakage current. The power down current spec includes any such leakage from the A/D module. 2: VREF input current is from External VREF+, or VREF-, or AVSS, or AVDD pin, whichever is selected as reference input. 3: The A/D conversion result never decreases with an increase in the input voltage and has no missing codes. 1999 Microchip Technology Inc. Advanced Information DS41120A-page 171 PIC16C717/770/771 FIGURE 15-13: PIC16C770/771 AND PIC16LC770/771 A/D CONVERSION TIMING (NORMAL MODE) BSF ADCON0, GO 1/2 TCY 134 131 Q4 130 A/D CLK 11 A/D DATA 10 9 8 3 2 1 NEW_DATA OLD_DATA ADRES 0 ADIF GO SAMPLE Note 1: DONE SAMPLING STOPPED 132 If the A/D clock source is selected as RC, a time of TCY is added before the A/D clock starts. This allows the SLEEP instruction to be executed. TABLE 15-13: PIC16C770/771 AND PIC16LC770/771 A/D CONVERSION REQUIREMENTS Parameter No. 130* 130* Sym TAD TAD Characteristic Min Typ Max Units A/D clock period 1.6 -- -- s Tosc based, VREF 2.5V 3.0 -- -- s Tosc based, VREF full range 3.0 6.0 9.0 s ADCS<1:0> = 11 (RC mode) At VDD = 2.5V 2.0 4.0 6.0 s At VDD = 5.0V -- 13TAD -- TAD Set GO bit to new data in A/D result register Note 2 11.5 -- s 5* -- -- s The minimum time is the amplifier settling time. This may be used if the "new" input voltage has not changed by more than 1LSb (i.e 1mV @ 4.096V) from the last sampled voltage (as stated on CHOLD). -- TOSC/2 -- -- If the A/D clock source is selected as RC, a time of TCY is added before the A/D clock starts. This allows the SLEEP instruction to be executed. A/D Internal RC oscillator period 131* TCNV Conversion time (not including acquisition time) (Note 1) 132* TACQ Acquisition Time 134* TGO Q4 to A/D clock start Conditions * These parameters are characterized but not tested. Data in "Typ" column is at 5V, 25C unless otherwise stated. These parameters are for design guidance only and are not tested. Note 1: ADRES register may be read on the following TCY cycle. 2: See Section 11.6 for minimum conditions. DS41120A-page 172 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 FIGURE 15-14: PIC16C770/771 AND PIC16LC770/771 A/D CONVERSION TIMING (SLEEP MODE) BSF ADCON0, GO 134 131 Q4 130 A/D CLK 11 A/D DATA 10 9 8 3 2 1 OLD_DATA ADRES 0 NEW_DATA ADIF GO SAMPLE Note 1: DONE SAMPLING STOPPED 132 If the A/D clock source is selected as RC, a time of TCY is added before the A/D clock starts. This allows the SLEEP instruction to be executed. TABLE 15-14: PIC16C770/771 AND PIC16LC770/771 A/D CONVERSION REQUIREMENTS Parameter No. 130* 130* Sym TAD TAD Characteristic Min Typ Max Units A/D clock period 1.6 -- -- s VREF 2.5V TBD -- -- s VREF full range 3.0 6.0 9.0 s ADCS<1:0> = 11 (RC mode) At VDD = 3.0V 2.0 4.0 6.0 s At VDD = 5.0V -- 13TAD -- -- Note 2 11.5 -- s 5* -- -- s The minimum time is the amplifier settling time. This may be used if the "new" input voltage has not changed by more than 1LSb (i.e 1mV @ 4.096V) from the last sampled voltage (as stated on CHOLD). -- TOSC/2 + TCY -- -- If the A/D clock source is selected as RC, a time of TCY is added before the A/D clock starts. This allows the SLEEP instruction to be executed. A/D Internal RC oscillator period 131* TCNV Conversion time (not including acquisition time) (Note 1) 132* TACQ Acquisition Time 134* TGO Q4 to A/D clock start Conditions * These parameters are characterized but not tested. Data in "Typ" column is at 5V, 25C unless otherwise stated. These parameters are for design guidance only and are not tested. Note 1: ADRES register may be read on the following TCY cycle. 2: See Section 11.6 for minimum conditions. 1999 Microchip Technology Inc. Advanced Information DS41120A-page 173 PIC16C717/770/771 TABLE 15-15: PIC16C717 AND PIC16LC717 A/D CONVERTER CHARACTERISTICS: Param No. Sym Characteristic Min Typ Max Units Conditions A01 NR Resolution -- -- 10 bits bit Min. resolution for A/D is 4.1 mV, VREF+ = AVDD = 4.096V, VREF- = AVSS = 0V, VREF- VAIN VREF+ A03 EIL Integral error -- -- TBD -- VREF+ = AVDD = 4.096V, VREF- = AVSS = 0V, VREF- VAIN VREF+ A04 EDL Differential error -- -- TBD -- No missing codes to 10 bits VREF+ = AVDD = 4.096V, VREF- = AVSS = 0V, VREF- VAIN VREF+ A06 EOFF Offset error -- -- TBD -- VREF+ = AVDD = 4.096V, VREF- = AVSS = 0V, VREF- VAIN VREF+ A07 EGN Gain Error -- -- TBD LSb VREF+ = AVDD = 4.096V, VREF- = AVSS = 0V, VREF- VAIN VREF+ A10 -- Monotonicity -- guaranteed(3) -- -- AVSS VAIN VREF+ A20 VREF Reference voltage (VREF+ VREF-) 4.096 -- VDD +0.3V V Absolute minimum electrical spec to ensure 10-bit accuracy. A21 VREF+ Reference V High (AVDD or VREF+) VREF- -- AVDD V Min. resolution for A/D is 4.1 mV A22 VREF- Reference V Low (AVSS or VREF-) AVSS -- VREF+ V Min. resolution for A/D is 4.1 mV A25 VAIN Analog input voltage VREFL -- VREFH V A30 ZAIN Recommended impedance of analog voltage source -- -- 2.5 k A50 IREF VREF input current (Note 2) -- -- 10 A During VAIN acquisition. Based on differential of VHOLD to VAIN. To charge CHOLD see Section 11.0. During A/D conversion cycle. * These parameters are characterized but not tested. Data in "Typ" column is at 5V, 25C unless otherwise stated. These parameters are for design guidance only and are not tested. Note 1: When A/D is off, it will not consume any current other than leakage current. The power down current spec includes any such leakage from the A/D module. 2: VREF current is from External VREF+, or VREF-, or AVSS, or AVDD pin, whichever is selected as reference input. 3: The A/D conversion result never decreases with an increase in the input voltage and has no missing codes. DS41120A-page 174 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 FIGURE 15-15: PIC16C717 A/D CONVERSION TIMING (NORMAL MODE) BSF ADCON0, GO 134 1/2 TCY 131 Q4 130 A/D CLK 9 A/D DATA 8 7 6 3 2 1 0 NEW_DATA OLD_DATA ADRES ADIF GO SAMPLE Note 1: DONE SAMPLING STOPPED 132 If the A/D clock source is selected as RC, a time of TCY is added before the A/D clock starts. This allows the SLEEP instruction to be executed. TABLE 15-16: PIC16C717 AND PIC16LC717 A/D CONVERSION REQUIREMENTS Parameter No. Sym Characteristic Min Typ Max Units 1.6 -- -- s Tosc based, VREF 2.5V 3.0 -- -- s Tosc based, VREF full range 3.0 6.0 9.0 s 2.0 4.0 6.0 s At VDD = 5.0V -- 11TAD -- TAD Set GO bit to new data in A/D result register Note 2 11.5 -- s 5* -- -- s The minimum time is the amplifier settling time. This may be used if the "new" input voltage has not changed by more than 1LSb (i.e 1mV @ 4.096V) from the last sampled voltage (as stated on CHOLD). -- TOSC/2 -- -- If the A/D clock source is selected as RC, a time of TCY is added before the A/D clock starts. This allows the SLEEP instruction to be executed. 130* TAD A/D clock period 130* TAD A/D Internal RC oscillator period 131* TCNV Conversion time (not including acquisition time) (Note 1) 132* TACQ Acquisition Time 134* TGO Q4 to A/D clock start Conditions ADCS<1:0> = 11 (RC mode) At VDD = 2.5V * These parameters are characterized but not tested. Data in "Typ" column is at 5V, 25C unless otherwise stated. These parameters are for design guidance only and are not tested. Note 1: ADRES register may be read on the following TCY cycle. 2: See Section 11.6 for minimum conditions. 1999 Microchip Technology Inc. Advanced Information DS41120A-page 175 PIC16C717/770/771 FIGURE 15-16: PIC16C717 A/D CONVERSION TIMING (SLEEP MODE) BSF ADCON0, GO 134 131 Q4 130 A/D CLK 9 A/D DATA 8 7 6 3 2 1 NEW_DATA OLD_DATA ADRES 0 ADIF GO SAMPLE Note 1: DONE SAMPLING STOPPED 132 If the A/D clock source is selected as RC, a time of TCY is added before the A/D clock starts. This allows the SLEEP instruction to be executed. TABLE 15-17: PIC16C717 AND PIC16LC717 A/D CONVERSION REQUIREMENTS Parameter No. 130* 130* Sym TAD TAD Characteristic Min Typ Max Units A/D clock period 1.6 -- -- s VREF 2.5V TBD -- -- s VREF full range 3.0 6.0 9.0 s ADCS<1:0> = 11 (RC mode) At VDD = 3.0V 2.0 4.0 6.0 s At VDD = 5.0V -- 11TAD -- -- Note 2 11.5 -- s 5* -- -- s The minimum time is the amplifier settling time. This may be used if the "new" input voltage has not changed by more than 1LSb (i.e 1mV @ 4.096V) from the last sampled voltage (as stated on CHOLD). -- TOSC/2 + TCY -- -- If the A/D clock source is selected as RC, a time of TCY is added before the A/D clock starts. This allows the SLEEP instruction to be executed. A/D Internal RC oscillator period 131* TCNV Conversion time (not including acquisition time) (Note 1) 132* TACQ Acquisition Time 134* TGO Q4 to A/D clock start Conditions * These parameters are characterized but not tested. Data in "Typ" column is at 5V, 25C unless otherwise stated. These parameters are for design guidance only and are not tested. Note 1: ADRES register may be read on the following TCY cycle. 2: See Section 11.6 for minimum conditions. DS41120A-page 176 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 16.0 DC AND AC CHARACTERISTICS GRAPHS AND TABLES The graphs and tables provided in this section are for design guidance and are not tested. In some graphs or tables, the data presented are outside specified operating range (i.e., outside specified VDD range). This is for information only. The data presented in this section is a statistical summary of data collected on units from different lots over a period of time and matrix samples. 'Typical' represents the mean of the distribution at 25C. 'Max' or 'min' represents (mean + 3) or (mean - 3) respectively, where is standard deviation, over the whole temperature range. Graphs and Tables not available at this time. 1999 Microchip Technology Inc. Advanced Information DS41120A-page 177 PIC16C717/770/771 NOTES: DS41120A-page 178 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 17.0 PACKAGING INFORMATION 17.1 Package Marking Information 18-Lead PDIP Example XXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXX YYWWNNN PIC16C717/P 9917017 18-Lead CERDIP Windowed Example XXXXXXXX XXXXXXXX YYWWNNN PIC16C717/JW 9905017 Example 18-Lead SOIC XXXXXXXXXXXX XXXXXXXXXXXX XXXXXXXXXXXX PIC16C717/SO 9910017 YYWWNNN Example 20-Lead PDIP PIC16C770/P XXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXX YYWWNNN Legend: MM...M XX...X YY WW NNN Note: * 9917017 Microchip part number information Customer specific information* Year code (last 2 digits of calendar year) Week code (week of January 1 is week `01') Alphanumeric traceability code In the event the full Microchip part number cannot be marked on one line, it will be carried over to the next line thus limiting the number of available characters for customer specific information. Standard OTP marking consists of Microchip part number, year code, week code, facility code, mask rev#, and assembly code. For OTP marking beyond this, certain price adders apply. Please check with your Microchip Sales Office. For QTP devices, any special marking adders are included in QTP price. 1999 Microchip Technology Inc. Advanced Information DS41120A-page 179 PIC16C717/770/771 Package Marking Information (Cont'd) 20-Lead SSOP Example XXXXXXXXXXX XXXXXXXXXXX PIC16C770 20I/SS YYWWNNN 9917017 20-Lead CERDIP Windowed Example PIC16C770/JW XXXXXXXX XXXXXXXX YYWWNNN 20-Lead SOIC Example XXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXXXXXX YYWWNNN DS41120A-page 180 9905017 PIC16C771/SO Advanced Information 9910017 1999 Microchip Technology Inc. PIC16C717/770/771 17.2 18-Lead Plastic Dual In-line (P) - 300 mil (PDIP) E1 D 2 n 1 E A2 A L c A1 B1 p B eB Units Dimension Limits n p MIN INCHES* NOM 18 .100 .155 .130 MAX MILLIMETERS NOM 18 2.54 3.56 3.94 2.92 3.30 0.38 7.62 7.94 6.10 6.35 22.61 22.80 3.18 3.30 0.20 0.29 1.14 1.46 0.36 0.46 7.87 9.40 5 10 5 10 MIN Number of Pins Pitch Top to Seating Plane A .140 .170 Molded Package Thickness A2 .115 .145 Base to Seating Plane A1 .015 Shoulder to Shoulder Width E .300 .313 .325 Molded Package Width E1 .240 .250 .260 Overall Length D .890 .898 .905 Tip to Seating Plane L .125 .130 .135 c Lead Thickness .008 .012 .015 Upper Lead Width B1 .045 .058 .070 Lower Lead Width B .014 .018 .022 Overall Row Spacing eB .310 .370 .430 Mold Draft Angle Top 5 10 15 Mold Draft Angle Bottom 5 10 15 *Controlling Parameter Notes: Dimensions D and E1 do not include mold flash or protrusions. Mold flash or protrusions shall not exceed .010" (0.254mm) per side. JEDEC Equivalent: MS-001 Drawing No. C04-007 1999 Microchip Technology Inc. Advanced Information MAX 4.32 3.68 8.26 6.60 22.99 3.43 0.38 1.78 0.56 10.92 15 15 DS41120A-page 181 PIC16C717/770/771 17.3 18-Lead Ceramic Dual In-line with Window (JW) - 300 mil (CERDIP) E1 D W2 2 n 1 W1 E A2 A c L A1 eB B1 p B Units Dimension Limits n p Number of Pins Pitch Top to Seating Plane Ceramic Package Height Standoff Shoulder to Shoulder Width Ceramic Pkg. Width Overall Length Tip to Seating Plane Lead Thickness Upper Lead Width Lower Lead Width Overall Row Spacing Window Width Window Length *Controlling Parameter JEDEC Equivalent: MO-036 Drawing No. C04-010 DS41120A-page 182 A A2 A1 E E1 D L c B1 B eB W1 W2 MIN .170 .155 .015 .300 .285 .880 .125 .008 .050 .016 .345 .130 .190 INCHES* NOM 18 .100 .183 .160 .023 .313 .290 .900 .138 .010 .055 .019 .385 .140 .200 MAX .195 .165 .030 .325 .295 .920 .150 .012 .060 .021 .425 .150 .210 Advanced Information MILLIMETERS NOM 18 2.54 4.32 4.64 3.94 4.06 0.38 0.57 7.62 7.94 7.24 7.37 22.35 22.86 3.18 3.49 0.20 0.25 1.27 1.40 0.41 0.47 8.76 9.78 3.30 3.56 4.83 5.08 MIN MAX 4.95 4.19 0.76 8.26 7.49 23.37 3.81 0.30 1.52 0.53 10.80 3.81 5.33 1999 Microchip Technology Inc. PIC16C717/770/771 17.4 18-Lead Plastic Small Outline (SO) - Wide, 300 mil (SOIC) E p E1 D 2 B n 1 h 45 c A2 A L Units Dimension Limits n p MIN A1 INCHES* NOM 18 .050 .099 .091 .008 .407 .295 .454 .020 .033 4 .011 .017 12 12 MAX MILLIMETERS NOM 18 1.27 2.36 2.50 2.24 2.31 0.10 0.20 10.01 10.34 7.39 7.49 11.33 11.53 0.25 0.50 0.41 0.84 0 4 0.23 0.27 0.36 0.42 0 12 0 12 MIN Number of Pins Pitch Overall Height A .093 .104 Molded Package Thickness A2 .088 .094 Standoff A1 .004 .012 Overall Width E .394 .420 Molded Package Width E1 .291 .299 Overall Length D .446 .462 Chamfer Distance h .010 .029 Foot Length L .016 .050 Foot Angle 0 8 c Lead Thickness .009 .012 Lead Width B .014 .020 Mold Draft Angle Top 0 15 Mold Draft Angle Bottom 0 15 *Controlling Parameter Notes: Dimensions D and E1 do not include mold flash or protrusions. Mold flash or protrusions shall not exceed .010" (0.254mm) per side. JEDEC Equivalent: MS-013 Drawing No. C04-051 1999 Microchip Technology Inc. Advanced Information MAX 2.64 2.39 0.30 10.67 7.59 11.73 0.74 1.27 8 0.30 0.51 15 15 DS41120A-page 183 PIC16C717/770/771 17.5 20-Lead Plastic Dual In-line (P) - 300 mil (PDIP) E1 D 2 n 1 E A2 A L c A1 B1 eB p B Units Dimension Limits n p MIN INCHES* NOM 20 .100 .155 .130 MAX MILLIMETERS NOM 20 2.54 3.56 3.94 2.92 3.30 0.38 7.49 7.87 6.10 6.35 26.04 26.24 3.05 3.30 0.20 0.29 1.40 1.52 0.36 0.46 7.87 9.40 5 10 5 10 MIN Number of Pins Pitch Top to Seating Plane A .140 .170 Molded Package Thickness A2 .115 .145 Base to Seating Plane A1 .015 Shoulder to Shoulder Width E .295 .310 .325 Molded Package Width E1 .240 .250 .260 Overall Length D 1.025 1.033 1.040 Tip to Seating Plane L .120 .130 .140 c Lead Thickness .008 .012 .015 Upper Lead Width B1 .055 .060 .065 Lower Lead Width B .014 .018 .022 Overall Row Spacing eB .310 .370 .430 Mold Draft Angle Top 5 10 15 Mold Draft Angle Bottom 5 10 15 *Controlling Parameter Notes: Dimensions D and E1 do not include mold flash or protrusions. Mold flash or protrusions shall not exceed .010" (0.254mm) per side. JEDEC Equivalent: MS-001 Drawing No. C04-019 DS41120A-page 184 Advanced Information MAX 4.32 3.68 8.26 6.60 26.42 3.56 0.38 1.65 0.56 10.92 15 15 1999 Microchip Technology Inc. PIC16C717/770/771 17.6 20-Lead Ceramic Dual In-line with Window (JW) - 300 mil (CERDIP) DRAWING NOT AVAILABLE 1999 Microchip Technology Inc. Advanced Information DS41120A-page 185 PIC16C717/770/771 17.7 20-Lead Plastic Small Outline (SO) - Wide, 300 mi (SOIC) E E1 p D 2 B n 1 h 45 c A2 A L Units Dimension Limits n p MIN A1 INCHES* NOM 20 .050 .099 .091 .008 .407 .295 .504 .020 .033 4 .011 .017 12 12 MAX MILLIMETERS NOM 20 1.27 2.36 2.50 2.24 2.31 0.10 0.20 10.01 10.34 7.39 7.49 12.60 12.80 0.25 0.50 0.41 0.84 0 4 0.23 0.28 0.36 0.42 0 12 0 12 MIN Number of Pins Pitch Overall Height A .093 .104 Molded Package Thickness A2 .088 .094 Standoff A1 .004 .012 Overall Width E .394 .420 Molded Package Width E1 .291 .299 Overall Length D .496 .512 Chamfer Distance h .010 .029 Foot Length L .016 .050 Foot Angle 0 8 c Lead Thickness .009 .013 Lead Width B .014 .020 Mold Draft Angle Top 0 15 Mold Draft Angle Bottom 0 15 *Controlling Parameter Notes: Dimensions D and E1 do not include mold flash or protrusions. Mold flash or protrusions shall not exceed .010" (0.254mm) per side. JEDEC Equivalent: MS-013 Drawing No. C04-094 DS41120A-page 186 Advanced Information MAX 2.64 2.39 0.30 10.67 7.59 13.00 0.74 1.27 8 0.33 0.51 15 15 1999 Microchip Technology Inc. PIC16C717/770/771 17.8 20-Lead Plastic Shrink Small Outline (SS) - 209 mil, 5.30 mm (SSOP) E E1 p D B 2 1 n c A2 A L A1 Units Dimension Limits n p Number of Pins Pitch Overall Height Molded Package Thickness Standoff Overall Width Molded Package Width Overall Length Foot Length Lead Thickness Foot Angle Lead Width Mold Draft Angle Top Mold Draft Angle Bottom A A2 A1 E E1 D L c B MIN .068 .064 .002 .299 .201 .278 .022 .004 0 .010 0 0 INCHES* NOM 20 .026 .073 .068 .006 .309 .207 .284 .030 .007 4 .013 5 5 MAX .078 .072 .010 .322 .212 .289 .037 .010 8 .015 10 10 MILLIMETERS NOM 20 0.66 1.73 1.85 1.63 1.73 0.05 0.15 7.59 7.85 5.11 5.25 7.06 7.20 0.56 0.75 0.10 0.18 0.00 101.60 0.25 0.32 0 5 0 5 MIN MAX 1.98 1.83 0.25 8.18 5.38 7.34 0.94 0.25 203.20 0.38 10 10 *Controlling Parameter Notes: Dimensions D and E1 do not include mold flash or protrusions. Mold flash or protrusions shall not exceed .010" (0.254mm) per side. JEDEC Equivalent: MO-150 Drawing No. C04-072 1999 Microchip Technology Inc. Advanced Information DS41120A-page 187 PIC16C717/770/771 NOTES: DS41120A-page 188 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 APPENDIX A: REVISION HISTORY Version Date Revision Description A 9/16/99 This is a new data sheet. However, the devices described in this data sheet are the upgrades to the devices found in the PIC16C7X Data Sheet, DS30390E. APPENDIX B: DEVICE DIFFERENCES The differences between the devices in this data sheet are listed in Table B-1. TABLE B-1: DEVICE DIFFERENCES Difference PIC16C717 PIC16C770 PIC16C771 Program Memory 2K 2K 4K 6 channels, 10 bits 6 channels, 12 bits 6 channels, 12 bits Not available Available Available 18-pin PDIP, 18-pin windowed CERDIP, 18-pin SOIC, 20-pin SSOP 20-pin PDIP, 20-pin windowed CERDIP, 20-pin SOIC, 20-pin SSOP 20-pin PDIP, 20-pin windowed CERDIP, 20-pin SOIC, 20-pin SSOP A/D Dedicated AVDD and AVSS Packages 1999 Microchip Technology Inc. Advanced Information DS41120A-page 189 PIC16C717/770/771 NOTES: DS41120A-page 190 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 INDEX A C A/D .................................................................................... 113 A/D Converter Enable (ADIE Bit) ................................ 19 ADCON0 Register..................................................... 113 ADCON1 Register............................................. 113, 115 ADRES Register ....................................................... 113 Block Diagram........................................................... 117 Configuring Analog Port............................................ 116 Conversion time ........................................................ 123 Conversions .............................................................. 119 converter characteristics ................... 169, 170, 171, 174 Faster Conversion - Lower Resolution Tradeoff ....... 123 Internal Sampling Switch (Rss) Impedence .............. 121 Operation During Sleep ............................................ 124 Sampling Requirements............................................ 121 Sampling Time .......................................................... 121 Source Impedance.................................................... 121 Special Event Trigger (CCP)....................................... 57 A/D Conversion Clock ....................................................... 118 ACK..................................................................................... 78 Acknowledge Data bit, AKD ................................................ 70 Acknowledge Pulse............................................................. 78 Acknowledge Sequence Enable bit, AKE ........................... 70 Acknowledge Status bit, AKS ............................................. 70 ACKSTAT ........................................................................... 92 ADCON0 Register............................................................. 113 ADCON1 Register..................................................... 113, 115 ADRES.............................................................................. 113 ADRES Register ........................................... 13, 14, 113, 124 AKD..................................................................................... 70 AKE ..................................................................................... 70 AKS ..................................................................................... 70 Application Note AN578, "Use of the SSP Module in the I2C Multi-Master Environment."................................................. 77 Architecture PIC16C717/PIC16C717 Block Diagram ....................... 5 PIC16C770/771/PIC16C770/771 Block Diagram ......... 6 Assembler MPASM Assembler................................................... 149 B Banking, Data Memory ................................................. 11, 16 Baud Rate Generator .......................................................... 86 BF ..................................................................... 68, 78, 92, 95 Block Diagrams Baud Rate Generator.................................................. 86 I2C Master Mode......................................................... 84 I2C Module .................................................................. 77 RA3:RA0 and RA5 Port Pins .................... 28, 30, 31, 37 SSP (I2C Mode) .......................................................... 77 SSP (SPI Mode).......................................................... 71 BOR. See Brown-out Reset BRG .................................................................................... 86 Brown-out Reset (BOR) .................................... 125, 131, 132 Buffer Full bit, BF ................................................................ 78 Buffer Full Status bit, BF ..................................................... 68 Bus Arbitration .................................................................. 103 Bus Collision Section ........................................................ 103 Bus Collision During a RESTART Condition..................... 106 Bus Collision During a Start Condition .............................. 104 Bus Collision During a Stop Condition .............................. 107 1999 Microchip Technology Inc. Capture (CCP Module) ....................................................... 56 Block Diagram ............................................................ 56 CCP Pin Configuration ............................................... 56 CCPR1H:CCPR1L Registers ..................................... 56 Changing Between Capture Prescalers ..................... 56 Software Interrupt ....................................................... 56 Timer1 Mode Selection............................................... 56 CCP1CON .......................................................................... 15 CCP2CON .......................................................................... 15 CCPR1H Register......................................................... 13, 15 CCPR1L Register ............................................................... 15 CCPR2H Register............................................................... 15 CCPR2L Register ............................................................... 15 CKE .................................................................................... 68 CKP .................................................................................... 69 Clock Polarity Select bit, CKP............................................. 69 Code Examples Loading the SSPBUF register .................................... 72 Code Protection ........................................................ 125, 139 Compare (CCP Module) ..................................................... 56 Block Diagram ............................................................ 57 CCP Pin Configuration ............................................... 56 CCPR1H:CCPR1L Registers ..................................... 56 Software Interrupt ....................................................... 56 Special Event Trigger ........................................... 51, 57 Timer1 Mode Selection............................................... 56 Configuration Bits ............................................................. 125 D D/A...................................................................................... 68 Data Memory ...................................................................... 11 Bank Select (RP<1:0> Bits).................................. 11, 16 General Purpose Registers ........................................ 11 Register File Map ....................................................... 12 Special Function Registers......................................... 13 Data/Address bit, D/A ......................................................... 68 DC Characteristics PIC16C717/770/771 ................................................. 158 Development Support ....................................................... 149 Device Differences............................................................ 189 Direct Addressing ............................................................... 25 E Enhanced Capture/Compare/PWM (CCP) CCP1 CCPR1H Register .............................................. 55 CCPR1L Register ............................................... 55 Enable (CCP1IE Bit)........................................... 19 Timer Resources ........................................................ 56 Enhanced Capture/Compare/PWM (ECCP)....................... 55 External Power-on Reset Circuit....................................... 130 F Firmware Instructions ....................................................... 141 Flowcharts Acknowledge .............................................................. 99 Master Receiver ......................................................... 96 Master Transmit.......................................................... 93 Restart Condition........................................................ 90 Start Condition............................................................ 88 Stop Condition .......................................................... 101 FSR Register .......................................................... 13, 14, 15 Advanced Information DS41120A-page 191 PIC16C717/770/771 G GCE .................................................................................... 70 General Call Address Sequence......................................... 83 General Call Address Support ............................................ 83 General Call Enable bit, GCE ............................................. 70 I I/O Ports .............................................................................. 27 I2C ....................................................................................... 77 I2C Master Mode Receiver Flowchart ................................. 96 I2C Master Mode Reception................................................ 95 I2C Master Mode Restart Condition .................................... 89 I2C Mode Selection ............................................................. 77 I2C Module Acknowledge Flowchart .............................................. 99 Acknowledge Sequence timing ................................... 98 Addressing .................................................................. 78 Baud Rate Generator .................................................. 86 Block Diagram............................................................. 84 BRG Block Diagram .................................................... 86 BRG Reset due to SDA Collision .............................. 105 BRG Timing ................................................................ 86 Bus Arbitration .......................................................... 103 Bus Collision ............................................................. 103 Acknowledge..................................................... 103 Restart Condition .............................................. 106 Restart Condition Timing (Case1)..................... 106 Restart Condition Timing (Case2)..................... 106 Start Condition .................................................. 104 Start Condition Timing .............................. 104, 105 Stop Condition .................................................. 107 Stop Condition Timing (Case1)......................... 107 Stop Condition Timing (Case2)......................... 107 Transmit Timing ................................................ 103 Bus Collision timing................................................... 103 Clock Arbitration........................................................ 102 Clock Arbitration Timing (Master Transmit)............... 102 Conditions to not give ACK Pulse ............................... 78 General Call Address Support .................................... 83 Master Mode ............................................................... 84 Master Mode 7-bit Reception timing ........................... 97 Master Mode Operation .............................................. 85 Master Mode Start Condition ...................................... 87 Master Mode Transmission......................................... 92 Master Mode Transmit Sequence ............................... 85 Master Transmit Flowchart ......................................... 93 Multi-Master Communication .................................... 103 Multi-master Mode ...................................................... 85 Operation .................................................................... 77 Repeat Start Condition timing ..................................... 89 Restart Condition Flowchart........................................ 90 Slave Mode ................................................................. 78 Slave Reception .......................................................... 79 Slave Transmission..................................................... 79 SSPBUF...................................................................... 78 Start Condition Flowchart............................................ 88 Stop Condition Flowchart .......................................... 101 Stop Condition Receive or Transmit timing............... 100 Stop Condition timing ................................................ 100 Waveforms for 7-bit Reception ................................... 80 Waveforms for 7-bit Transmission .............................. 80 I2C Module Address Register, SSPADD............................. 78 I2C Slave Mode ................................................................... 78 ID Locations .............................................................. 125, 139 In-Circuit Serial Programming (ICSP) ....................... 125, 139 INDF.................................................................................... 15 INDF Register ............................................................... 13, 14 DS41120A-page 192 Indirect Addressing ............................................................. 25 FSR Register .............................................................. 11 Instruction Format............................................................. 141 Instruction Set................................................................... 141 ADDLW..................................................................... 143 ADDWF..................................................................... 143 ANDLW..................................................................... 143 ANDWF..................................................................... 143 BCF .......................................................................... 143 BSF........................................................................... 143 BTFSC ...................................................................... 144 BTFSS ...................................................................... 144 CALL......................................................................... 144 CLRF ........................................................................ 144 CLRW ....................................................................... 144 CLRWDT .................................................................. 144 COMF ....................................................................... 145 DECF ........................................................................ 145 DECFSZ ................................................................... 145 GOTO ....................................................................... 145 INCF ......................................................................... 145 INCFSZ..................................................................... 145 IORLW ...................................................................... 146 IORWF...................................................................... 146 MOVF ....................................................................... 146 MOVLW .................................................................... 146 MOVWF .................................................................... 146 NOP .......................................................................... 146 RETFIE ..................................................................... 147 RETLW ..................................................................... 147 RETURN................................................................... 147 RLF ........................................................................... 147 RRF .......................................................................... 147 SLEEP ...................................................................... 147 SUBLW ..................................................................... 148 SUBWF..................................................................... 148 SWAPF ..................................................................... 148 XORLW .................................................................... 148 XORWF .................................................................... 148 Summary Table ........................................................ 142 INTCON .............................................................................. 15 INTCON Register................................................................ 18 GIE Bit ........................................................................ 18 INTE Bit ...................................................................... 18 INTF Bit ...................................................................... 18 PEIE Bit ...................................................................... 18 RBIE Bit ...................................................................... 18 RBIF Bit ................................................................ 18, 35 T0IE Bit ....................................................................... 18 T0IF Bit ....................................................................... 18 Inter-Integrated Circuit (I2C) ............................................... 67 internal sampling switch (Rss) impedence ....................... 121 Interrupt Sources ...................................................... 125, 135 Block Diagram .......................................................... 135 Capture Complete (CCP)............................................ 56 Compare Complete (CCP).......................................... 56 RB0/INT Pin, External............................................... 136 TMR0 Overflow................................................... 48, 136 TMR1 Overflow..................................................... 49, 51 TMR2 to PR2 Match ................................................... 54 TMR2 to PR2 Match (PWM) ................................. 53, 58 Interrupts Synchronous Serial Port Interrupt............................... 20 Interrupts, Context Saving During..................................... 136 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 Interrupts, Enable Bits A/D Converter Enable (ADIE Bit) ................................ 19 CCP1 Enable (CCP1IE Bit)................................... 19, 56 Global Interrupt Enable (GIE Bit) ........................ 18, 135 Interrupt on Change (RB7:RB4) Enable (RBIE Bit) ............................................................ 18, 136 Peripheral Interrupt Enable (PEIE Bit) ........................ 18 PSP Read/Write Enable (PSPIE Bit) .......................... 19 RB0/INT Enable (INTE Bit) ......................................... 18 SSP Enable (SSPIE Bit) ............................................. 19 TMR0 Overflow Enable (T0IE Bit)............................... 18 TMR1 Overflow Enable (TMR1IE Bit) ......................... 19 TMR2 to PR2 Match Enable (TMR2IE Bit) ................. 19 USART Receive Enable (RCIE Bit) ............................ 19 Interrupts, Flag Bits CCP1 Flag (CCP1IF Bit) ............................................. 56 Interrupt on Change (RB7:RB4) Flag (RBIF Bit) ...................................................... 18, 35, 136 RB0/INT Flag (INTF Bit).............................................. 18 TMR0 Overflow Flag (T0IF Bit) ........................... 18, 136 INTRC Mode ..................................................................... 128 K KeeLoq Evaluation and Programming Tools.................. 152 M Master Clear (MCLR) MCLR Reset, Normal Operation ............... 129, 131, 132 MCLR Reset, SLEEP................................ 129, 131, 132 Memory Organization Data Memory .............................................................. 11 Program Memory ........................................................ 11 MPLAB Integrated Development Environment Software .. 149 Multi-Master Communication ............................................ 103 Multi-Master Mode .............................................................. 85 O OPCODE Field Descriptions ............................................. 141 OPERATION ....................................................................... 45 OPTION_REG Register ...................................................... 17 INTEDG Bit ................................................................. 17 PS Bits .................................................................. 17, 47 PSA Bit.................................................................. 17, 47 RBPU Bit..................................................................... 17 T0CS Bit................................................................ 17, 47 T0SE Bit................................................................ 17, 47 Oscillator Configuration..................................................... 126 CLKOUT ................................................................... 128 Dual Speed Operation for ER and INTRC Modes .... 128 EC ............................................................. 126, 127, 131 ER ..................................................................... 126, 131 ER Mode ................................................................... 128 HS ..................................................................... 126, 131 INTRC ............................................................... 126, 131 LP...................................................................... 126, 131 XT ..................................................................... 126, 131 Oscillator, Timer1 .......................................................... 49, 51 Oscillator, WDT ................................................................. 137 P P.......................................................................................... 68 Packaging ......................................................................... 179 Paging, Program Memory ............................................. 11, 24 Parallel Slave Port (PSP) Read/Write Enable (PSPIE Bit)................................... 19 PCL Register................................................................. 13, 14 PCLATH Register ................................................... 13, 14, 15 PCON Register ........................................................... 23, 131 1999 Microchip Technology Inc. PICDEM-1 Low-Cost PICmicro Demo Board ................... 151 PICDEM-2 Low-Cost PIC16CXX Demo Board................. 151 PICDEM-3 Low-Cost PIC16CXXX Demo Board .............. 151 PICSTART Plus Entry Level Development System.......... 151 PIE1 Register ..................................................................... 19 ADIE Bit ...................................................................... 19 CCP1IE Bit ................................................................. 19 PSPIE Bit.................................................................... 19 RCIE Bit...................................................................... 19 SSPIE Bit.................................................................... 19 TMR1IE Bit ................................................................. 19 TMR2IE Bit ................................................................. 19 PIE2 Register ..................................................................... 21 Pinout Descriptions PIC16C717 ................................................................... 9 PIC16C770 ................................................................... 7 PIC16C770/771 ............................................................ 7 PIC16C771 ................................................................... 7 PIR1 Register ..................................................................... 20 PIR2 Register ..................................................................... 22 PMCON1 ............................................................................ 43 Pointer, FSR ....................................................................... 25 POR. See Power-on Reset PORTA ............................................................................... 15 Initialization................................................................. 28 PORTA Register......................................................... 27 TRISA Register........................................................... 27 PORTA Register ......................................................... 13, 124 PORTB ............................................................................... 15 Initialization................................................................. 35 PORTB Register......................................................... 35 Pull-up Enable (RBPU Bit).......................................... 17 RB0/INT Edge Select (INTEDG Bit) ........................... 17 RB0/INT Pin, External .............................................. 136 RB7:RB4 Interrupt on Change.................................. 136 RB7:RB4 Interrupt on Change Enable (RBIE Bit)........................................................... 18, 136 RB7:RB4 Interrupt on Change Flag (RBIF Bit)...................................................... 18, 35, 136 TRISB Register........................................................... 35 PORTB Register ......................................................... 13, 124 Postscaler, Timer2 Select (TOUTPS Bits)................................................. 53 Postscaler, WDT................................................................. 47 Assignment (PSA Bit) ........................................... 17, 47 Block Diagram ............................................................ 48 Rate Select (PS Bits)............................................ 17, 47 Switching Between Timer0 and WDT ......................... 48 Power-on Reset (POR)..................... 125, 129, 130, 131, 132 Oscillator Start-up Timer (OST)........................ 125, 130 Power Control (PCON) Register............................... 131 Power-down (PD Bit) .................................................. 16 Power-on Reset Circuit, External ............................. 130 Power-up Timer (PWRT) .................................. 125, 130 Time-out (TO Bit)........................................................ 16 Time-out Sequence .................................................. 131 Time-out Sequence on Power-up..................... 133, 134 PR2 Register ...................................................................... 14 Prescaler, Capture.............................................................. 56 Prescaler, Timer0 ............................................................... 47 Assignment (PSA Bit) ........................................... 17, 47 Block Diagram ............................................................ 48 Rate Select (PS Bits)............................................ 17, 47 Switching Between Timer0 and WDT ......................... 48 Prescaler, Timer1 ............................................................... 50 Select (T1CKPS Bits) ................................................. 49 Advanced Information DS41120A-page 193 PIC16C717/770/771 Prescaler, Timer2................................................................ 59 Select (T2CKPS Bits).................................................. 53 PRO MATE II Universal Programmer............................. 151 Program .............................................................................. 43 Program Counter PCL Register............................................................... 24 PCLATH Register ............................................... 24, 136 Reset Conditions....................................................... 131 Program Memory ................................................................ 11 Interrupt Vector ........................................................... 11 Paging ................................................................... 11, 24 Program Memory Map ................................................ 11 Reset Vector ............................................................... 11 Program Verification.......................................................... 139 Programmable Brown-out Reset (PBOR) ................. 129, 130 Programming, Device Instructions .................................... 141 PWM (CCP Module)............................................................ 58 Block Diagram............................................................. 58 CCPR1H:CCPR1L Registers ...................................... 58 Duty Cycle................................................................... 59 Output Diagram........................................................... 59 Period.......................................................................... 58 TMR2 to PR2 Match ............................................. 53, 58 TMR2 to PR2 Match Enable (TMR2IE Bit) ................. 19 Q Q-Clock ............................................................................... 59 R R/W ..................................................................................... 68 R/W bit ................................................................................ 78 R/W bit ................................................................................ 79 RAM. See Data Memory RCE,Receive Enable bit, RCE ............................................ 70 RCREG ............................................................................... 15 RCSTA Register.................................................................. 15 Read/Write bit, R/W ............................................................ 68 READING............................................................................ 45 Receive Overflow Indicator bit, SSPOV .............................. 69 Register File ........................................................................ 11 Register File Map ................................................................ 12 Registers FSR Summary ............................................................ 15 INDF Summary ........................................................... 15 INTCON Summary ...................................................... 15 PCL Summary............................................................. 15 PCLATH Summary ..................................................... 15 PORTB Summary ....................................................... 15 SSPSTAT.................................................................... 68 STATUS Summary ..................................................... 15 TMR0 Summary .......................................................... 15 TRISB Summary ......................................................... 15 Reset......................................................................... 125, 129 Block Diagram........................................................... 129 Brown-out Reset (BOR). See Brown-out Reset (BOR) MCLR Reset. See MCLR Power-on Reset (POR). See Power-on Reset (POR) Reset Conditions for All Registers ............................ 132 Reset Conditions for PCON Register........................ 131 Reset Conditions for Program Counter ..................... 131 Reset Conditions for STATUS Register .................... 131 Restart Condition Enabled bit, RSE .................................... 70 Revision History ................................................................ 189 RSE..................................................................................... 70 S SAE ..................................................................................... 70 SCK..................................................................................... 71 DS41120A-page 194 SCL..................................................................................... 78 SDA .................................................................................... 78 SDI...................................................................................... 71 SDO .................................................................................... 71 SEEVAL Evaluation and Programming System............. 152 Serial Clock, SCK ............................................................... 71 Serial Clock, SCL................................................................ 78 Serial Data Address, SDA .................................................. 78 Serial Data In, SDI .............................................................. 71 Serial Data Out, SDO ......................................................... 71 Slave Select Synchronization ............................................. 74 Slave Select, SS ................................................................. 71 SLEEP .............................................................. 125, 129, 138 SMP .................................................................................... 68 Software Simulator (MPLAB-SIM) .................................... 150 SPE..................................................................................... 70 Special Features of the CPU ............................................ 125 Special Function Registers ................................................. 13 PIC16C717 ................................................................. 13 PIC16C717/770/771 ................................................... 13 PIC16C770 ................................................................. 13 PIC16C771 ................................................................. 13 Speed, Operating.................................................................. 1 SPI Master Mode............................................................... 73 Serial Clock................................................................. 71 Serial Data In .............................................................. 71 Serial Data Out ........................................................... 71 Serial Peripheral Interface (SPI) ................................. 67 Slave Select................................................................ 71 SPI Clock .................................................................... 73 SPI Mode .................................................................... 71 SPI Clock Edge Select, CKE .............................................. 68 SPI Data Input Sample Phase Select, SMP ....................... 68 SPI Master/Slave Connection............................................. 72 SPI Module Master/Slave Connection............................................ 72 Slave Mode................................................................. 74 Slave Select Synchronization ..................................... 74 Slave Synch Timnig .................................................... 74 SS ....................................................................................... 71 SSP..................................................................................... 67 Block Diagram (SPI Mode) ......................................... 71 Enable (SSPIE Bit) ..................................................... 19 SPI Mode .................................................................... 71 SSPADD ..................................................................... 78 SSPBUF ............................................................... 73, 78 SSPCON1 .................................................................. 69 SSPCON2 .................................................................. 70 SSPSR ................................................................. 73, 78 SSPSTAT ............................................................. 68, 77 TMR2 Output for Clock Shift................................. 53, 54 SSP I2C SSP I2C Operation ..................................................... 77 SSP Module SPI Master Mode ........................................................ 73 SPI Master./Slave Connection.................................... 72 SPI Slave Mode .......................................................... 74 SSPCON1 Register .................................................... 77 SSP Overflow Detect bit, SSPOV....................................... 78 SSPADD Register............................................................... 14 SSPBUF ....................................................................... 15, 78 SSPBUF Register ............................................................... 13 SSPCON Register .............................................................. 13 SSPCON1..................................................................... 69, 77 SSPCON2........................................................................... 70 SSPEN................................................................................ 69 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 SSPIF............................................................................ 20, 79 SSPM3:SSPM0................................................................... 69 SSPOV.................................................................... 69, 78, 95 SSPSTAT...................................................................... 68, 77 SSPSTAT Register ............................................................. 14 Stack ................................................................................... 24 Start bit (S) .......................................................................... 68 Start Condition Enabled bit, SAE ........................................ 70 STATUS Register ....................................................... 16, 136 C Bit ............................................................................ 16 DC Bit.......................................................................... 16 IRP Bit......................................................................... 16 PD Bit.......................................................................... 16 RP1:RP0 Bits .............................................................. 16 TO Bit.......................................................................... 16 Z Bit............................................................................. 16 Status Register ................................................................... 16 Stop bit (P) .......................................................................... 68 Stop Condition Enable bit ................................................... 70 Synchronous Serial Port ..................................................... 67 Synchronous Serial Port Enable bit, SSPEN ...................... 69 Synchronous Serial Port Interrupt ....................................... 20 Synchronous Serial Port Mode Select bits, SSPM<3:0>......................................................................... 69 T T1CON ................................................................................ 15 T1CON Register ........................................................... 15, 49 T1CKPS Bits ............................................................... 49 T1OSCEN Bit.............................................................. 49 T1SYNC Bit................................................................. 49 TMR1CS Bit ................................................................ 49 TMR1ON Bit................................................................ 49 T2CON Register ........................................................... 15, 53 T2CKPS Bits ............................................................... 53 TMR2ON Bit................................................................ 53 TOUTPS Bits .............................................................. 53 Timer0 ................................................................................. 47 Block Diagram............................................................. 47 Clock Source Edge Select (T0SE Bit)................... 17, 47 Clock Source Select (T0CS Bit)............................ 17, 47 Overflow Enable (T0IE Bit) ......................................... 18 Overflow Flag (T0IF Bit)...................................... 18, 136 Overflow Interrupt ............................................... 48, 136 Timer1 ................................................................................. 49 Block Diagram............................................................. 50 Capacitor Selection..................................................... 51 Clock Source Select (TMR1CS Bit) ............................ 49 External Clock Input Sync (T1SYNC Bit) .................... 49 Module On/Off (TMR1ON Bit)..................................... 49 Oscillator ............................................................... 49, 51 Oscillator Enable (T1OSCEN Bit) ............................... 49 Overflow Enable (TMR1IE Bit).................................... 19 Overflow Interrupt ................................................. 49, 51 Special Event Trigger (CCP)................................. 51, 57 T1CON Register ......................................................... 49 TMR1H Register ......................................................... 49 TMR1L Register.......................................................... 49 Timer2 Block Diagram............................................................. 54 PR2 Register......................................................... 53, 58 SSP Clock Shift..................................................... 53, 54 T2CON Register ......................................................... 53 TMR2 Register............................................................ 53 TMR2 to PR2 Match Enable (TMR2IE Bit) ................. 19 TMR2 to PR2 Match Interrupt ......................... 53, 54, 58 1999 Microchip Technology Inc. Timing Diagrams Acknowledge Sequence Timing ................................. 98 Baud Rate Generator with Clock Arbitration............... 86 BRG Reset Due to SDA Collision............................. 105 Brown-out Reset....................................................... 164 Bus Collision Start Condition Timing ...................................... 104 Bus Collision During a Restart Condition (Case 1)... 106 Bus Collision During a Restart Condition (Case2).... 106 Bus Collision During a Start Condition (SCL = 0) ..... 105 Bus Collision During a Stop Condition...................... 107 Bus Collision for Transmit and Acknowledge ........... 103 Capture/Compare/PWM ........................................... 166 CLKOUT and I/O ...................................................... 162 External Clock Timing............................................... 162 I2C Master Mode First Start bit timing ........................ 87 I2C Master Mode Reception timing............................. 97 I2C Master Mode Transmission timing ....................... 94 Master Mode Transmit Clock Arbitration .................. 102 Power-up Timer ........................................................ 164 Repeat Start Condition ............................................... 89 Reset ........................................................................ 164 Slave Synchronization ................................................ 74 Start-up Timer........................................................... 164 Stop Condition Receive or Transmit ......................... 100 Time-out Sequence on Power-up..................... 133, 134 Timer0 ...................................................................... 165 Timer1 ...................................................................... 165 Wake-up from SLEEP via Interrupt .......................... 139 Watchdog Timer ....................................................... 164 TMR0 .................................................................................. 15 TMR0 Register.................................................................... 13 TMR1H ............................................................................... 15 TMR1H Register ................................................................. 13 TMR1L ................................................................................ 15 TMR1L Register.................................................................. 13 TMR2 .................................................................................. 15 TMR2 Register.................................................................... 13 TRISA Register........................................................... 14, 124 TRISB Register........................................................... 14, 124 TXREG ............................................................................... 15 U Update Address, UA ........................................................... 68 USART Receive Enable (RCIE Bit) ......................................... 19 W W Register ........................................................................ 136 Wake-up from SLEEP............................................... 125, 138 Interrupts .......................................................... 131, 132 MCLR Reset ............................................................. 132 Timing Diagram ........................................................ 139 WDT Reset ............................................................... 132 Watchdog Timer (WDT)............................................ 125, 137 Block Diagram .......................................................... 137 Enable (WDTE Bit) ................................................... 137 Programming Considerations ................................... 137 RC Oscillator ............................................................ 137 Time-out Period ........................................................ 137 WDT Reset, Normal Operation................. 129, 131, 132 WDT Reset, SLEEP ......................................... 131, 132 Waveform for General Call Address Sequence.................. 83 WCOL ................................................. 69, 87, 92, 95, 98, 100 WCOL Status Flag.............................................................. 87 Write Collision Detect bit, WCOL........................................ 69 WWW, On-Line Support ....................................................... 3 Advanced Information DS41120A-page 195 PIC16C717/770/771 NOTES: DS41120A-page 196 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 ON-LINE SUPPORT Systems Information and Upgrade Hot Line Microchip provides on-line support on the Microchip World Wide Web (WWW) site. The web site is used by Microchip as a means to make files and information easily available to customers. To view the site, the user must have access to the Internet and a web browser, such as Netscape or Microsoft Explorer. Files are also available for FTP download from our FTP site. The Systems Information and Upgrade Line provides system users a listing of the latest versions of all of Microchip's development systems software products. Plus, this line provides information on how customers can receive any currently available upgrade kits.The Hot Line Numbers are: 1-800-755-2345 for U.S. and most of Canada, and 1-480-786-7302 for the rest of the world. Connecting to the Microchip Internet Web Site 981103 The Microchip web site is available by using your favorite Internet browser to attach to: www.microchip.com The file transfer site is available by using an FTP service to connect to: ftp://ftp.microchip.com The web site and file transfer site provide a variety of services. Users may download files for the latest Development Tools, Data Sheets, Application Notes, User's Guides, Articles and Sample Programs. A variety of Microchip specific business information is also available, including listings of Microchip sales offices, distributors and factory representatives. Other data available for consideration is: * Latest Microchip Press Releases * Technical Support Section with Frequently Asked Questions * Design Tips * Device Errata * Job Postings * Microchip Consultant Program Member Listing * Links to other useful web sites related to Microchip Products * Conferences for products, Development Systems, technical information and more * Listing of seminars and events 1999 Microchip Technology Inc. Trademarks: The Microchip name, logo, PIC, PICmicro, PICSTART, PICMASTER and PRO MATE are registered trademarks of Microchip Technology Incorporated in the U.S.A. and other countries. FlexROM, MPLAB and fuzzyLAB are trademarks and SQTP is a service mark of Microchip in the U.S.A. All other trademarks mentioned herein are the property of their respective companies. Advanced Information DS41120A-page197 PIC16C717/770/771 READER RESPONSE It is our intention to provide you with the best documentation possible to ensure successful use of your Microchip product. If you wish to provide your comments on organization, clarity, subject matter, and ways in which our documentation can better serve you, please FAX your comments to the Technical Publications Manager at (480) 786-7578. Please list the following information, and use this outline to provide us with your comments about this Data Sheet. To: Technical Publications Manager RE: Reader Response Total Pages Sent From: Name Company Address City / State / ZIP / Country Telephone: (_______) _________ - _________ FAX: (______) _________ - _________ Application (optional): Would you like a reply? Y Device: PIC16C717/770/771 N Literature Number: DS41120A Questions: 1. What are the best features of this document? 2. How does this document meet your hardware and software development needs? 3. Do you find the organization of this data sheet easy to follow? If not, why? 4. What additions to the data sheet do you think would enhance the structure and subject? 5. What deletions from the data sheet could be made without affecting the overall usefulness? 6. Is there any incorrect or misleading information (what and where)? 7. How would you improve this document? 8. How would you improve our software, systems, and silicon products? DS41120A-page198 Advanced Information 1999 Microchip Technology Inc. PIC16C717/770/771 PIC16C717/770/771 PRODUCT IDENTIFICATION SYSTEM To order or obtain information, e.g., on pricing or delivery refer to the factory or the listed sales office. PART NO. - Examples X /XX XXX Pattern: QTP, SQTP, Code or Special Requirements Package: JW SO P SS = = = = Temperature Range: I = 0C to +70C = -40C to +85C Device PIC16C771 : VDD range 4.0V to 5.5V PIC16C771T : VDD range 4.0V to 5.5V (Tape/Reel) PIC16LC771 : VDD range 2.5V to 5.5V PIC16LC771T: VDD range 2.5V to 5.5V (Tape/Reel) Windowed CERDIP SOIC PDIP SSOP a) PIC16C771/P Commercial Temp., PDIP Package, normal VDD limits. * JW Devices are UV erasable and can be programmed to any device configuration. JW Devices meet the electrical requirement of each oscillator type (including LC devices). Sales and Support Data Sheets Products supported by a preliminary Data Sheet may have an errata sheet describing minor operational differences and recommended workarounds. To determine if an errata sheet exists for a particular device, please contact one of the following: 1. 2. 3. Your local Microchip sales office The Microchip Corporate Literature Center U.S. FAX: (480) 786-7277 The Microchip Worldwide Site (www.microchip.com) Please specify which device, revision of silicon and Data Sheet (include Literature #) you are using. New Customer Notification System Register on our web site (www.microchip.com/cn) to receive the most current information on our products. 1999 Microchip Technology Inc. Advanced Information DS41120A-page 199 WORLDWIDE SALES AND SERVICE AMERICAS AMERICAS (continued) Corporate Office Toronto Singapore Microchip Technology Inc. 2355 West Chandler Blvd. Chandler, AZ 85224-6199 Tel: 480-786-7200 Fax: 480-786-7277 Technical Support: 480-786-7627 Web Address: http://www.microchip.com Microchip Technology Inc. 5925 Airport Road, Suite 200 Mississauga, Ontario L4V 1W1, Canada Tel: 905-405-6279 Fax: 905-405-6253 Microchip Technology Singapore Pte Ltd. 200 Middle Road #07-02 Prime Centre Singapore 188980 Tel: 65-334-8870 Fax: 65-334-8850 Atlanta Microchip Asia Pacific Unit 2101, Tower 2 Metroplaza 223 Hing Fong Road Kwai Fong, N.T., Hong Kong Tel: 852-2-401-1200 Fax: 852-2-401-3431 Microchip Technology Inc. 500 Sugar Mill Road, Suite 200B Atlanta, GA 30350 Tel: 770-640-0034 Fax: 770-640-0307 Boston Microchip Technology Inc. 5 Mount Royal Avenue Marlborough, MA 01752 Tel: 508-480-9990 Fax: 508-480-8575 Chicago Microchip Technology Inc. 333 Pierce Road, Suite 180 Itasca, IL 60143 Tel: 630-285-0071 Fax: 630-285-0075 Dallas Microchip Technology Inc. 4570 Westgrove Drive, Suite 160 Addison, TX 75248 Tel: 972-818-7423 Fax: 972-818-2924 Dayton Microchip Technology Inc. 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Tri-Atria Office Building 32255 Northwestern Highway, Suite 190 Farmington Hills, MI 48334 Tel: 248-538-2250 Fax: 248-538-2260 Los Angeles Microchip Technology Inc. 18201 Von Karman, Suite 1090 Irvine, CA 92612 Tel: 949-263-1888 Fax: 949-263-1338 New York Microchip Technology Inc. 150 Motor Parkway, Suite 202 Hauppauge, NY 11788 Tel: 631-273-5305 Fax: 631-273-5335 San Jose Microchip Technology Inc. 2107 North First Street, Suite 590 San Jose, CA 95131 Tel: 408-436-7950 Fax: 408-436-7955 ASIA/PACIFIC Hong Kong ASIA/PACIFIC (continued) Taiwan, R.O.C Microchip Technology Taiwan 10F-1C 207 Tung Hua North Road Taipei, Taiwan, ROC Tel: 886-2-2717-7175 Fax: 886-2-2545-0139 EUROPE Beijing United Kingdom Microchip Technology, Beijing Unit 915, 6 Chaoyangmen Bei Dajie Dong Erhuan Road, Dongcheng District New China Hong Kong Manhattan Building Beijing 100027 PRC Tel: 86-10-85282100 Fax: 86-10-85282104 Arizona Microchip Technology Ltd. 505 Eskdale Road Winnersh Triangle Wokingham Berkshire, England RG41 5TU Tel: 44 118 921 5858 Fax: 44-118 921-5835 India Denmark Microchip Technology Inc. India Liaison Office No. 6, Legacy, Convent Road Bangalore 560 025, India Tel: 91-80-229-0061 Fax: 91-80-229-0062 Microchip Technology Denmark ApS Regus Business Centre Lautrup hoj 1-3 Ballerup DK-2750 Denmark Tel: 45 4420 9895 Fax: 45 4420 9910 Japan France Microchip Technology Intl. Inc. Benex S-1 6F 3-18-20, Shinyokohama Kohoku-Ku, Yokohama-shi Kanagawa 222-0033 Japan Tel: 81-45-471- 6166 Fax: 81-45-471-6122 Arizona Microchip Technology SARL Parc d'Activite du Moulin de Massy 43 Rue du Saule Trapu Batiment A - ler Etage 91300 Massy, France Tel: 33-1-69-53-63-20 Fax: 33-1-69-30-90-79 Korea Germany Microchip Technology Korea 168-1, Youngbo Bldg. 3 Floor Samsung-Dong, Kangnam-Ku Seoul, Korea Tel: 82-2-554-7200 Fax: 82-2-558-5934 Arizona Microchip Technology GmbH Gustav-Heinemann-Ring 125 D-81739 Munchen, Germany Tel: 49-89-627-144 0 Fax: 49-89-627-144-44 Shanghai Arizona Microchip Technology SRL Centro Direzionale Colleoni Palazzo Taurus 1 V. Le Colleoni 1 20041 Agrate Brianza Milan, Italy Tel: 39-039-65791-1 Fax: 39-039-6899883 Microchip Technology RM 406 Shanghai Golden Bridge Bldg. 2077 Yan'an Road West, Hong Qiao District Shanghai, PRC 200335 Tel: 86-21-6275-5700 Fax: 86 21-6275-5060 Italy 11/15/99 Microchip received QS-9000 quality system certification for its worldwide headquarters, design and wafer fabrication facilities in Chandler and Tempe, Arizona in July 1999. The Company's quality system processes and procedures are QS-9000 compliant for its PICmicro(R) 8-bit MCUs, KEELOQ(R) code hopping devices, Serial EEPROMs and microperipheral products. In addition, Microchip's quality system for the design and manufacture of development systems is ISO 9001 certified. All rights reserved. (c) 1999 Microchip Technology Incorporated. Printed in the USA. 11/99 Printed on recycled paper. Information contained in this publication regarding device applications and the like is intended for suggestion only and may be superseded by updates. No representation or warranty is given and no liability is assumed by Microchip Technology Incorporated with respect to the accuracy or use of such information, or infringement of patents or other intellectual property rights arising from such use or otherwise. Use of Microchip's products as critical components in life support systems is not authorized except with express written approval by Microchip. No licenses are conveyed, implicitly or otherwise, under any intellectual property rights. The Microchip logo and name are registered trademarks of Microchip Technology Inc. in the U.S.A. and other countries. All rights reserved. All other trademarks mentioned herein are the property of their respective companies. 1999 Microchip Technology Inc.