I2CWRITE and 18F4680

[mister_e]

Are you using a OSC module or crystal?

[ecoli-557]

I am now using a 20 MHz oscillator fed into A.7
I also tried downloading the MPASM again from the MELABS site - no change.....

[mister_e]

Don't forget, the timeout label OF I2CWRITE perform a GOTO not a GOSUB, maybe why you have odd results.... stack underflow.

What happen if you loop within the INIT section?

init:
        pause 1000 'Hold here for a bit while things IPL......
        LCDOUT $FE,1,"I'm alive!"
        heart=1 'Turns off HEARTBEAT led
        fault=1 'Turns off FAULT led
        for i2c_addr=0 to 7
             i2cwrite idata,iclock,$06,i2c_addr,[$00,$FF] 'Sets GP0.0-GP0.7 as OUTPUTS
             pause 20
             i2cwrite idata,iclock,$07,i2c_addr,[$FF,$00] 'Sets GP1.0-GP1.7 as INPUTS
             pause 20
             next
        GOTO init

[ecoli-557]

Mr. E-
I added a GOTO at the end of the INIT section (tight loop) and still the pins don't reflect any movement - they are both high.

BTW, MPASM 5.14, MCS 2.3.0.0, PBP 2.47.

I am no Guru but have coded before and this is driving me nuts! 2 different board designs but using the same chip gives the same symptom.......I swear it seems that the command offers no response.

[mister_e]

Is the LCD's working?

[ecoli-557]

Yes, all esle is working as expected. When I start a project I use the LCD as a debugging tool and all the messages I write to it are working. ALso the heartbeat LED is blinking showing me that I am looping in the main part and that the proc is counting correctly.

Everything BUT the I2C commands - nothing from the pin!!

[mister_e]

Well that's strange... i have activity here on both pins with the same PIC, but 20MHZ external crystal (not the problem here as your LCD work)

PBP 2.50, MPASM 5.20.

I would check for a short somewhere...