A more common compiler requirement is do this
kind of operation with out changing register C
unless it is needed. ie pre-setting C has lots
of problems if C is volitile. I think that will take
6 instructions. (can it be done in less?)

         btfsc   A
         btfss   B
         goto   clear
         bsf     C
         goto   done
clear  bcf     C
done

Walter Banks
http://www.bytecraft.com

>
> Scott Dattalo wrote:
>
> > How fast can you logically AND two bits?
> >
> > Given:
> >  bit_a  of register A
> >  bit_b  of register B
> >  bit_c  of register C
> >
> > The goal in C parlance is:
> >
> >   C.bit_c = A.bit_a & B.bit_b;
>
> John Payson wrote:
> >
> >
> >         bsf     C
> >         btfsc   A
> >          btfss  B
> >          bcf    C