Ed Todd <PICLIST@MITVMA.MIT.EDU> wrote:

> Here is the way I do it for 16 bit in assembler.  There are some
> simple macros I use based on the CARRY bit too.
>
>         MOVFW   A3
>         ADDWF   B3,F
>         IFCARRY
>         INCF            B2,F
>         MOVFW   A2
>         ADDWF   B2,F
>         IFCARRY
>         INCF            B1,F
>         MOVFW   A1
>         ADDWF   B1,F
>         IFCARRY
>         INCF            B0,F
>         MOVFW   A0
>         ADDWF   B0,F
>         IFCARRY
>         GOTO            OVERFLOW

Ed:

Your code is essentially the same as the example that started this
thread.  Like that example, it won't work.

Use your routine to perform the following two additions (each of
which should give the same result):

      0000FFFF        00000001
    + 00000001      + 0000FFFF

See why it fails?

-Andy

=== Andrew Warren - fastfwd@ix.netcom.com
=== Fast Forward Engineering - Vista, California
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