Dwayne Reid wrote:
>
> At 12:44 AM 6/10/01 +1000, Roman Black wrote:
>
> >There are a few custom designed mnemonics that are not
> >official Microchip ones, but which are really handy,
> >I got these from Olin,
> >
> >SKPWGT   skip if w greater than
> >SKPWLE   skip if w less or equal
> >SKPWEQ   skip if w equal
> >SKPWNE   skip if w not equal
>
> I've got a few more that I find useful:
>
> 12 bit core only:
>
> tstw            MACRO           ;test w, valid Z; C & DC unchanged
>      xorlw       0
>      endm

Clever! Never thought of using that one! :o)


>
> comw            MACRO           ;complement W, valid Z; C & DC unchanged
>      xorlw       0xFF
>      endm
>
> 12 bit and 14 bit core parts:
>
> decw            MACRO                   ;decrement w, valid Z, C & DC trashed
>      addlw       -1
>      endm                                ;C & DC =1 if w>0 after decrement
>
> negw            MACRO                   ;negate w
>      sublw       0
>      endm                                ;valid z; C & DC trashed
>
> And you are right: Olin's 1 line macros were (are) a great idea - thanks,
> Olin!


Absolutely! And may I ask is there any gain from
making these one-inst mnemonics as macros and not
just using #defines?

I use:
#define   NEGW   sublw d'0'     ; negate w

-Roman

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