At 08:17 AM 7/9/2010, you wrote:


Are you trying to modify someone else's code extracted from an
existing PIC design?




>The original I2C code goes like this (a part of it).
>
>txbyte          movlw .8
>                 movwf bitctr
>                 btfss txbuf,7
>                 goto $+3
>                 bsf iicport,sda
>                 goto $+3
>                 bcf iicport,sda
>                 goto $+1
>                 goto $+1
>                 bsf iicport,scl
>                 goto $+1
>                 goto $+1
>                 bcf iicport,scl
>                 rlf txbuf,same
>                 decfsz bitctr,same
>                 goto $-0Dh
>                 bsf iicport,scl
>                 bsf iicport,sda
>                 retlw 0
>
>
> > If it works then it is probably a read-write-modify issue, which occurs
> > when a pin hasn't changed enough before the next bcf or bsf happens.
>
>This code would work for me on 16C54's years back.
>
>Cheers
>
>Ravi
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