John Considine wrote:
>
> I am trying to have a variable be decremented and that result be used as
> the BTFSC test bit
>
> For example
>
> movlw    H'07'
> movwf    TestBit
> decf        TestBit, 1
> btfsc       PORTB, TestBit
>
> Is this possible,  I tried using indirect referencing like
>
> movlw    TestBit
> movwf    FSR
> btfsc       PORTB, INDF
>
> but that will not work. Any suggestions.
> Thanks

You cannot use BTFSC like that. (?)

You may need to try something like...

        movlw b'10000000'
        movwf TestBit

        - - - -

        bcf status,carry        ; shift bit one position to right
        rrf TestBit
        btfsc status,carry      ; if carry = 1 then reset bit 7 = 1
        rrf TextBit

        - - - -

        movf PORTB,w            ; do bit comparison on port
        andwf TestBit,w
        btfsc status,Z
        goto BitIsOne

--
Best regards

Tony

http://www.picnpoke.com
Email sales@picnpoke.com