Scott writes:
>
> Try this untested code:
>
>        MOVF    PORTA,W         ;Get the current state of PORTA,4
>        XORWF   index_flag,W    ;Compare to the saved state.
>        ANDLW   1<<4            ;Only interested in PORTA,4
>
>        SKPNZ
>         goto   no_change
>
>   ;Change in states was detected
>        XORWF   index_flag,F    ;Save state for next time.
>
>        ;"Index_now" code goes here.
>
>
>no_change

Thanks for the new method. I had to change it a little since it detected
both edges and I needed falling edges. This is what I came up with:

        MOVF    PORTA,W         ;Get the current state of PORTA,4
        XORWF   index_flag,W    ;Compare to the saved state.
        ANDLW   1<<4            ;Only interested in PORTA,4

        SKPNZ
         goto   Dont_care

   ;Change in states was detected
        XORWF   index_flag,F    ;Save state for next time.
        btfsc   index_flag,F    ;only want falling edges
        goto    Dont_care
        ;"Index_now" code goes here.

This is much better than my two methods, because changing it from detecting
rising edges to falling edges only requires one change, from btfsc to btfss.

I will also look at your debounce code on your web page.

Thanks, Bob