Thanx John and everyone else who responded to this note.

I will update the 16 bit multiply with 32 bit result tomorrow.

myke

>
>
>|To fix this, I came up with the following code with the optional pieces, not
>|only will the result be correct, but the carry value as well.
>
>|I would appreciate it if you could look at it and comment on any
>|problems/better ways of doing it.
>
>The following brilliancy (not mine) will save many instructions:
>
>       movf    source,w
>       btfsc   C
>        incfsz source,w
>        addwf  dest,f
>
>This will add /source/ to /dest/, with correct carry propagation
>in and out.  The code is tricky, but it does handle all cases
>correctly.  Note that the final result must be put in /dest/ for
>this trick to work.  Replacing the ",f" on the last instruction
>with ",w" will cause the code to fail in the source==FF+carry case.
>
>
>
>

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