>-----Original Message-----
>From: CaptMasterX@CS.COM [mailto:CaptMasterX@CS.COM]
>Sent: Monday, March 17, 2003 12:47 PM
>To: PICLIST@MITVMA.MIT.EDU
>Subject: [PIC] 16F628 ASM Language question
>
>
>The instruction set for the 16F628 looks kinda skimpy.  Is there any =
way to
>test wreg against a certain byte and jump if it's equal.  They have
>instructions to test each bit, but to test against a byte, i'd have to =
write
>a function to go through and test every bit before i got the answer.  =
is
>there an easier way?
>
>--

I'll offer one way, though I doubt it's the "most efficient"

***WARNING.. Untested code for example only**********

To compare W with a literal and GOTO if equal:

        XORLW           Literal
        BTFSC           STATUS,Z
        GOTO            values_match

Or similar, to compare W with another register

        XORWF           testfile,W
        BTFSC           STATUS,Z
        GOTO            values_match

Both of these trash the W value, replacing it with
zero if equal, or a mask of the bits that are different
if not zero.

XOR (Exclusive OR) tests two byte values. The resulting bits
are ON for different and OFF for same.
i.e. which bits are different.


Good Luck,
Lyle

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