Re: [stella] JoustPong on the home stretch

Subject: Re: [stella] JoustPong on the home stretch
From: KirkIsrael@xxxxxxxxxxxxx
Date: 2 Mar 2004 21:54:21 -0000
> > So, I have a curious bug maybe people can look at--but 
> > only in Z26 (my ROM totally blows up in StellaX -- is 
> > that because of Thomas's SLEEP Macro, or what?) 
> I think the SLEEP macro uses undocumented opcodes in it's
> default state. StellaX doesn't support these. There should
> be a compiler switch that you can define to make the macro
> compile to only normal opcodes instead.

Yeah, I gotta look into that.
I don't think I'm using SLEEP for that much too important 
anymore.  (though if it's a multiple of 2, isn't SLEEP
"safe" re: undocumented opcodes?)
> > When the user hits Select in Z26 to return to the title
> > screen, the music starts going nuts and starts listing a 
> > huuuge framerate. It plays fine, and I can't duplicate the 
> > problem via supercharger on my 2600.
> Can you reproduce it reliably on the emulator? When I try
> hitting SELECT in your game, the sound plays just fine in z26.

Now, do you mean pressing Select *on* the title screen
(cycling through the gamemodes) or, what I meant to say 
but possibly wasn't clear, on the main gameplay screen, 
maybe even during a game, so it goes back to the title
screen. That's when I see it, and the framerate jumps 
to like 1300, though everything plays just fine. The sound
gets garbled as if ...I dunno, all the counters I'm using 
to do the music timing got set to zeros or 1s or other low
values, a garbled mess but at least it seems to be using 
the correct settings for AUDC*.

> But while working on the next version of z26 I had some situations,
> where it seemed as if there was an echo in the sound. Maybe
> the sound buffers get played twice or something. I can't figure
> out what triggers this, so it's a little difficult to find out
> what's going wrong.

Well, there was the framerate thing too...
when I'm home I'll try to give you the exact version of Z26 
I'm using.

> Is this what you are hearing, and do you have any idea how to
> trigger this? That would help me to find the bug in z26 and to
> fix it.

Yeah, not so much an echo, more like a timing garble. 

There is no god and Murphy is his prophet

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