Am I right in assuming that if you needed it rounded to the nearest
integer, you would just have to incf temp,F before the last rotate?

This will make a valuable addition to my math.asm, if you will let me
plagiarize :)

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> From: Scott Dattalo <sdattalo@UNIX.SRI.COM>
> To: PICLIST@MITVMA.MIT.EDU
> Subject: Re: Conversion of byte to percentage
> Date: Thursday, May 21, 1998 1:39 PM
>
> Justin Crooks wrote:
> >
> > > From: Scott Dattalo <sdattalo@UNIX.SRI.COM>
>
> <snip>
>
> > >
> > >         MOVWF   temp            ;Hex value is in W.
> > >         CLRC                    ;Clear the Carry bit so it doesn't
> > >         RRF     temp,F
> > >         CLRC
> > >         RRF     temp,F
> > >         CLRC
> > >         RRF     temp,F          ;temp = h>>3
> > >         ADDWF   temp,F          ;temp = h + (h>>3)
> > What happens if result > 0xFF?
>
>   The carry will get set and the next RRF will pick it up like a sponge
> soaks up water.
>
> > >         RRF     temp,F          ;temp = (h + (h>>3)) >> 1
> > >         ADDWF   temp,F          ;temp = h + ((h + (h>>3)) >> 1)
> > Again, same issue.
>
>   Again, same answer.
>
> > >         RRF     temp,F
> > >         CLRC
> > >         RRF     temp,W          ;d = W = (h + (h + (h>>3)) >> 1) >> 2
> > >
> > >         RETURN
> >
> > This is excellent, but will not work for values > 64%.  I like how
clean it
> > is, though.  You could add a line to check if MSB set.  Subtract 128 if
> > set, and add 50% at the end.
>
> The routine works just fine. Try it. The only limitation that it does
> have is that it actually computes floor(x * 100 / 256). So if your
> percentage is 88.7%, for example, you would get just 88%. For my
> application this was okay.
>
> Scott