> How the heckety heck did you figure out that the branch wasn't being
> taken after $7F?
>
> Changing the BPL to BNE fixed the problem, although I don't know why the
> problem existed in the first place. I can't see what would make the
> BLOW routine stop at $7F with a BPL in there, unless there is something
> about the nature of BPL that I just don't understand. Doesn't it just
> branch if the result is a positive number? BEQ branches if the result is
> zero, BMI branches if the result is a negative number, and BNE branches if
> the result is anything other than zero.
Well, you're right. BPL does branch if the result is a positive number.
But this is a BINARY positive/negative. Bit 7 is the sign bit: 0=pos 1=neg.
(and $FF= -1, and $FE= -2, etc).
And don't feel bad...I've got a good one along the same lines. I'll post it
to the list later...
-Chris
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