Re: [stella] How to make Stella (please help)

Subject: Re: [stella] How to make Stella (please help)
From: "B. Watson" <atari@xxxxxxxxxxxxxx>
Date: Tue, 18 Dec 2001 11:00:04 -0500 (EST)
On Tue, 18 Dec 2001, Thomas Jentzsch wrote:

> Thanks, you're right, version 3.0.x caused the problems.
> Now, if I could compile without running out of virtual memory, I would be completely happy :-)

Hey, you have virtual memory, in DOS? :)

> > I can't give you my modified Stella source... but, can I give you a
> > .diff that you can apply to your unmodified Stella source?
> Yes, please send it to me. I managed to recompile Stella and now Thrust isn't crashing the emulator anymore, but it behaves quite strange. Does it work with your version?

Nope... freezes up on game start. On standard error, it prints:
Illegal Instruction! a7

...which is LAX zeropage... which is something I haven't added to my xstella
source yet (I only added LAX (zp),y)..

So I've just now added LAX zeropage, recompiled, and now Thrust seems to
work just fine, at least for the 5 or 10 seconds I manage to keep from
getting killed (I think this is due to me being bad at the game, not an
emulator bug or anything) :)

> > Bradford Mott, are you still on this list? Does distributing patches to be
> > applied to Stella violate the intent of your license? (The letter of the
> > license doesn't say, one way or another, but the intent is what counts)
> There was a thread about illegal opcodes in February where Brad was asking for info about illegal opcodes:
> That was his last post to the list, so perhaps he isn't doing any Atari stuff anymore.

Well whatever he is doing, I hope it goes well... and I hope we see him here

Unlike DASM, when adding illegal instructions to Stella, you have to modify
2 different files, one of which has 3 tables (but only the timing table should
really *matter* during emulation, the others just give a name & addr. mode to
print if you've built Stella with debugging)... also unlike DASM, I can't
automate the entire process with a Perl script, since the code that actually
implements the emulated instruction doesn't really fit a template...

But if there's enough interest, and if I have enough time, it'll be a pretty
straightforward process to add them all. Also if Bradford doesn't mind (I'm
going to mail him directly & ask).. there are a few other modifications I'd
like to make, too (for one thing, a command-line switch to force PAL or NTSC
mode.. currently, to test the PAL version of my game, I have to generate a entry for it)

Meanwhile, I will send you, Thomas, author of Thrust, the modified Stella
source files you need to compile a version of Stella that can play Thrust. I
don't want to post it to the list without permission...


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