Greetings everybody. ;-)

Tracy Smith wrote:
>
> >I want to change   b7 b6 b5 b4 b3 b2 b1 b0   to  b0
> b1 b2 b3 b4 b5 b6 b7.
> >
> >Quickest & most code efficient??
>
> How about this... (John Payson)
>
>         movwf   source

        movfw   source  ;otherwise you put W to source

>         btfsc   source,0
>          xorlw  h'41'
>         btfsc   source,6
>          xorlw  h'41'

ok. swap 0 with 6

>         btfsc   source,1
>          xorlw  h'22'
>         btfsc   source,5
>          xorlw  h'22'

ok. swap 1 with 5

>         btfsc   source,2
>          xorlw  h'14'
>         btfsc   source,4
>          xorlw  h'14'

ok. swap 2 with 4

bit 3 is already on right place.

Here  is another reduced version:

        swapf   source,w        ;3210.654
        btfsc   source,3        ;swap bit 3 back
         xorlw  0x44            ;bit 7 is expected = 0
        btfsc   source,6
         xorlw  0x05
        btfsc   source,4        ;
         xorlw  0x05
        btfsc   source,2
         xorlw  0x50
        btfsc   source,0
         xorlw  0x50

I believe that there is more quick and compact version of this
(without ever table lookups) but I've no time to discover that.

WBR Dmitry.