Re: Re[3]: [stella] signed 8-bit comparisons?

Subject: Re: Re[3]: [stella] signed 8-bit comparisons?
From: KirkIsrael@xxxxxxxxxxxxx
Date: 5 Mar 2004 12:56:30 -0000
Just changing the subject, because i sent this under a different name 
and it hasn't come back to me :-( a blockage of my outgoing mail?

Tear my hair in frustration, because this is either something 
so retarded I shouldn't be in the 6507 business AT ALL, or something 
so subtle... 
two ASM files: 

---works, because I shoved in 3 NOPs around line 2730 

---doesn't work. I removed one of those 3 NOPs. 

Works = Pterry seems to fly smoothly and bounces at the right edge 

Not works = Pterry seems more herkyjerk and shows up on the left 
before finally switching direction. 

It is not an inherently time-sensitive piece of code. 
I don't know if it's: 
A. some odd memory alignment issue 
B. some odd timing issue 
C. one of Kirk's classic screwups, some mysterious missing "#" before 
   a constant or something like that--a quick inspection didn't 
   come up with anythi 

This is the simplest case I could make for the problem... 
the clc you see commented out was my first try at fixing it 
(I thought maybe it was carry problems doing a comparison, and 
the clc fixed it! apparently by doing what one of the NOPs is doing now.) 

Thank you, thank you if you can figure out what is up with this. 

I'm getting really nervous about this deadline I'd *really* like 
to make... 

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