Peter L. Peres wrote:
>
> ; #3 ! untested. (but need one ? ;)
>   rrf   INPUT, W
>   xorwf INPUT, F
>   rrf   INPUT, W
>   xorwf INPUT, F
>   rrf   INPUT, W
>   xorwf INPUT, F ; LSB = B3^B2^B1^B0
>
> ; optional laundry
>   movlw 1
>   andwf INPUT, F
>
> Peter

how 'bout

    rrf   INPUT, W
    xorwf INPUT, F
    rrf   INPUT, W
    xorwf INPUT, F
    rrf   INPUT, W
    xorwf INPUT, F ; LSB = B3^B2^B1^B0

; optional laundry
    rrf   INPUT, F ;(or W)
    skpc
     goto odd_parity
even_parity:


or (if we are destroying INPUT) a little faster:

    rlf    INPUT,w
    xorwf  INPUT,f
    rlf    INPUT,w
    rrf    INPUT,f
    xorwf  INPUT,f

    btfsc  INPUT,2
     goto  odd_parity

even_parity:


Scott