----- Original Message -----
From: Olin Lathrop <olin_piclist@COGNIVIS.COM>
To: <PICLIST@MITVMA.MIT.EDU>
Sent: Thursday, October 19, 2000 3:57 PM
Subject: Re: [PIC]: Number crunching, enclosed is 24x24 equ 48, have fun


> > > > movf    <somebyte>,W
> > > > skpnc
> > > > incfsz    <somebyte>,W
> > > > addwf    <resultbyte>,F
> > > >
>
> However, that brings up another problem.  If SOMEBYTE was 255 and there
was
> an incoming carry, the ADDWF will get skipped, which will prevent
RESULTBYTE
> from being set.  I am presuming here that the point of the code snippet is
> to perform an add with carry in/out of SOMEBYTE + RESULTBYTE -->
RESULTBYTE?
>

Olin, today is _not_ your day.

Yes, we skip setting <resultbyte> in the case that <somebyte> was 255 and
there was an incoming carry.

This is because we would have been adding 0 (255 plus the carry == 256, 256
mod 256 == 0) to <resultbyte>, anyway!

Bob Ammerman
RAm Systems
(contract development of high performance, high function, low-level
software)

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