Does that work for:

   0x0000ffff
 + 0x00000001
   ----------
   0x00010000

or does it result in
   0x00000000

ie:
if B2 is already 0xff then the INCF B2,F makes it zero but doesn't propogate
the new carry either as an overflow or into the next bytes.

John


At 07:34 AM 20/02/1997 -0700, you 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
>
>  <edtodd@sni.net>    Ed Todd
>
>
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