I2C Master/Slave 16F88/16F767 working code
Hi Guys,
After a few days of trying, I got this code to work. One 16F88 as master, and two 16F767 as slaves, just to test that the address is working fine. I only test to send one byte. I will have to test to read one, but wanted to share the code anyway:
Code:'--- MASTER BEGINS ---------------------------------------------------------------------------- @ device pic16f88, intrc_osc_noclkout ; system clock options @ device pic16f88, wdt_on ; watchdog timer @ device pic16f88, pwrt_on ; power-on timer @ device pic16f88, mclr_off ; master clear options (internal) @ device pic16f88, protect_off ; code protect off '--- DEFINE OSC 8 DEFINE I2C_HOLD 1 DEFINE I2C_SLOW 1 osccon = %01111000 '8mhz '--- cmcon = 7 ansel = 0 '--- scl VAR PORTB.4 ' i2c clock input sda VAR PORTB.1 ' i2c data input '--- main: High PORTA.6 Pause 500 Low PORTA.6 Pause 500 ' First 16f767 - address 6 I2CWrite sda, scl, $06, [15], bogus Pause 100 I2CWrite sda, scl, $06, [30], bogus Pause 100 ' Second 16f767 - address 8 I2CWrite sda, scl, $08, [45], bogus Pause 100 I2CWrite sda, scl, $08, [60], bogus Pause 100 GoTo main '--- bogus: GoTo main '--- End '--- MASTER ENDS ----------------------------------------------------------------------------Code:'--- FIRST SLAVE STARTS ---------------------------------------------------------------------------- @ DEVICE PIC16F767, INTRC_OSC_NOCLKOUT ; System Clock Options @ DEVICE PIC16F767, WDT_ON ; Watchdog Timer @ DEVICE PIC16F767, PWRT_ON ; Power-On Timer @ DEVICE PIC16F767, MCLR_OFF ; Master Clear Options (Internal) @ DEVICE PIC16F767, PROTECT_OFF ; Code Protect Off '--- DEFINE OSC 8 OSCCON = %01110000 '--- CMCON = 7 ' Comparators Off ADCON0 = 0 ' A/D Modules Off ADCON1 = %11111111 ' All Digital Pins TRISA = %00000000 '--- DEFINE I2C_HOLD 1 DEFINE I2C_SLOW 1 '--- ' Alias pins scl VAR PORTC.3 ' I2C clock input sda VAR PORTC.4 ' I2C data input '--- ' Define used register flags SSPIF VAR PIR1.3 ' SSP (I2C) interrupt flag BF VAR SSPSTAT.0 ' SSP (I2C) Buffer Full R_W VAR SSPSTAT.2 ' SSP (I2C) Read/Write D_A VAR SSPSTAT.5 ' SSP (I2C) Data/Address CKP VAR SSPCON.4 ' SSP (I2C) SCK Release Control SSPEN VAR SSPCON.5 ' SSP (I2C) Enable SSPOV VAR SSPCON.6 ' SSP (I2C) Receive Overflow Indicator WCOL VAR SSPCON.7 ' SSP (I2C) Write Collision Detect '--- ' Define constants I2Caddress CON 6 ' Make our address 6 '--- LEDA VAR PORTB.2 LEDB VAR PORTB.6 LEDC VAR PORTB.7 '--- ' Allocate RAM datain VAR BYTE ' Data in readcnt VAR BYTE dataout VAR BYTE[8] '--- ' Initialize I2C slave mode SSPADD = I2Caddress ' Set our address SSPCON2 = 0 ' General call address disabled SSPCON = $36 ' Set to I2C slave with 7-bit address '--- ' POST Low leda Pause 100 High leda Pause 100 Low leda Pause 100 High leda Pause 100 GoTo main '--- i2cslave: ' I2C slave subroutine SSPIF = 0 ' Clear interrupt flag IF R_W = 1 Then i2crd ' Read data from us IF BF = 0 Then i2cexit ' Nothing in buffer so exit IF D_A = 1 Then i2cwr ' Data for us (not address) IF SSPBUF != I2Caddress Then i2cexit ' Clear the address from the buffer readcnt = 0 ' Mark as first read GoTo i2cexit '--- i2cwr: ' I2C write data to us datain = SSPBUF ' Put data into array GoTo i2cexit '--- i2crd: ' I2C read data from us IF D_A = 0 Then readcnt = 0 ' Mark as first read EndIF SSPBUF = dataout[readcnt] ' Get data from array CKP = 1 ' Release SCL line readcnt = readcnt + 1 ' Move along read count GoTo i2cexit ' That's it '--- i2cexit: Return '--- main: IF SSPIF = 1 Then GoSub i2cslave Low leda Pause 10 High leda Pause 10 IF datain = 15 Then Low ledb Pause 10 High ledb Pause 10 EndIF IF datain = 30 Then Low ledc Pause 10 High ledc Pause 10 EndIF EndIF SSPOV = 0 WCOL = 0 GoTo main '--- End '--- FIRST SLAVE ENDS ----------------------------------------------------------------------------Hope it helps.Code:'--- SECOND SLAVE STARTS ---------------------------------------------------------------------------- @ DEVICE PIC16F767, INTRC_OSC_NOCLKOUT ; System Clock Options @ DEVICE PIC16F767, WDT_ON ; Watchdog Timer @ DEVICE PIC16F767, PWRT_ON ; Power-On Timer @ DEVICE PIC16F767, MCLR_OFF ; Master Clear Options (Internal) @ DEVICE PIC16F767, PROTECT_OFF ; Code Protect Off '--- DEFINE OSC 8 OSCCON = %01110000 '--- CMCON = 7 ' Comparators Off ADCON0 = 0 ' A/D Modules Off ADCON1 = %11111111 ' All Digital Pins TRISA = %00000000 '--- DEFINE I2C_HOLD 1 DEFINE I2C_SLOW 1 '--- ' Alias pins scl VAR PORTC.3 ' I2C clock input sda VAR PORTC.4 ' I2C data input '--- ' Define used register flags SSPIF VAR PIR1.3 ' SSP (I2C) interrupt flag BF VAR SSPSTAT.0 ' SSP (I2C) Buffer Full R_W VAR SSPSTAT.2 ' SSP (I2C) Read/Write D_A VAR SSPSTAT.5 ' SSP (I2C) Data/Address CKP VAR SSPCON.4 ' SSP (I2C) SCK Release Control SSPEN VAR SSPCON.5 ' SSP (I2C) Enable SSPOV VAR SSPCON.6 ' SSP (I2C) Receive Overflow Indicator WCOL VAR SSPCON.7 ' SSP (I2C) Write Collision Detect '--- ' Define constants I2Caddress CON 8 ' Make our address 8 '--- LEDA VAR PORTB.2 LEDB VAR PORTB.6 LEDC VAR PORTB.7 '--- ' Allocate RAM datain VAR BYTE ' Data in readcnt VAR BYTE dataout VAR BYTE[8] '--- ' Initialize I2C slave mode SSPADD = I2Caddress ' Set our address SSPCON2 = 0 ' General call address disabled SSPCON = $36 ' Set to I2C slave with 7-bit address '--- ' POST Low leda Pause 100 High leda Pause 100 Low leda Pause 100 High leda Pause 100 GoTo main '--- i2cslave: ' I2C slave subroutine SSPIF = 0 ' Clear interrupt flag IF R_W = 1 Then i2crd ' Read data from us IF BF = 0 Then i2cexit ' Nothing in buffer so exit IF D_A = 1 Then i2cwr ' Data for us (not address) IF SSPBUF != I2Caddress Then i2cexit ' Clear the address from the buffer readcnt = 0 ' Mark as first read GoTo i2cexit '--- i2cwr: ' I2C write data to us datain = SSPBUF ' Put data into array GoTo i2cexit '--- i2crd: ' I2C read data from us IF D_A = 0 Then readcnt = 0 ' Mark as first read EndIF SSPBUF = dataout[readcnt] ' Get data from array CKP = 1 ' Release SCL line readcnt = readcnt + 1 ' Move along read count GoTo i2cexit ' That's it '--- i2cexit: Return '--- main: IF SSPIF = 1 Then GoSub i2cslave Low leda Pause 10 High leda Pause 10 IF datain = 45 Then Low ledb Pause 10 High ledb Pause 10 EndIF IF datain = 60 Then Low ledc Pause 10 High ledc Pause 10 EndIF EndIF SSPOV = 0 WCOL = 0 GoTo main '--- End '--- SECOND SLAVE ENDS ----------------------------------------------------------------------------
Regards,
Daniel.
Re: I2C Master/Slave 16F88/16F767 working code
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