EPP mode parallel port comms

[mackrackit]

Maybe have the PC write to an EEPROM. Then at Pic boot time the EEPROM is read for a set of pre difined parameters ....

[cncmachineguy]

Thanks Dave, but thats where my brain gets foggy. For instance I can see how I would put a timer value in the EEPROM, then read it at boot time. But what if the user doesn't want to use the timer at all? Do I have an IF NoTimer then skip the timer section? And then would this get checked every time through the loop? that seems like the wrong way to implement it. But I can't think how to do it.

[mackrackit]

I think this is something like you want. It is quick and dirty with ON INT

'  18F6680  24FC1025
'<FL_PIC18F6680>'
    DEFINE OSC 20
    @ __CONFIG    _CONFIG1H, _OSC_HS_1H
    @ __CONFIG    _CONFIG2H, _WDT_OFF_2H & _WDTPS_128_2H
    @ __CONFIG    _CONFIG4L, _LVP_OFF_4L
    DEFINE LCD_DREG     PORTG
    DEFINE LCD_DBIT     0
    DEFINE LCD_RSREG    PORTE
    DEFINE LCD_RSBIT    0
    DEFINE LCD_EREG     PORTE
    DEFINE LCD_EBIT     1
    DEFINE LCD_BITS     4
    DEFINE LCD_LINES    4
    DEFINE LCD_COMMANDUS    3000
    DEFINE LCD_DATAUS   150
    PAUSE 1000
    DPIN    VAR PORTB.2    'I2C DATA PIN
    CPIN    VAR PORTB.1    'I2C CLOCK PIN
    ADDR    VAR WORD
    DATI    VAR BYTE[45]
    DATO    VAR WORD

    BOOT:
    LCDOUT $FE,1,"BOOTING"
    ADDR = 1
    'FOR TESTING DO A WRITE/READ TO THE EEPROM
    'CHANGE THE VALUE IN I2CWRITE TO TURN THE
    'TIMER ON OR OFF... THE SAME CAN BE DONE
    'FOR T0CON FOR DIFFERENT PWM
    I2CWRITE DPIN,CPIN,$A0,ADDR,[1]
    PAUSE 100
    I2CREAD DPIN,CPIN,$A0,ADDR,[INT_VAR]
    PAUSE 100
    INT_VAR VAR BYTE
    INTCON.5 = INT_VAR    'ENABLE/DISABLE TMR0
    T0CON = %10000000
    ON INTERRUPT GOTO TLOOP

    MAIN:
    LCDOUT $FE,1,"RUNNING"
    PAUSE 100
    GOTO MAIN

    DISABLE
    TLOOP:
    INTCON.2=0:TOGGLE PORTG.4
    RESUME: ENABLE

[cncmachineguy]

Thanks Dave, starting to have the fog clear a little now.