Re: [stella] Games using unofficial opcodes

Subject: Re: [stella] Games using unofficial opcodes
From: "Fred Quimby" <c9r@xxxxxxxxxxx>
Date: Thu, 2 Jun 2005 22:17:04 -0400
I investigated this and it turns out both emus do support RRA.  It turns out 
that my memory was wrong... I looked back through my code, and I made a 
comment to myself that I could use RRA in a certain case but it wouldn't 
save any bytes, which was the real reason I didn't use it.

And since my memory was wrong, I mistook a "n/a" for opcode $62 in Stella 
source to be where RRA was supposed to be, but of course $62 is really a JAM 
or HLT.  So I stand corrected, and now I will change my previous statement 
to be that you can find *everything* about illegal opcodes in emulator 
source code.

>From: "Eckhard Stolberg" <Eckhard_Stolberg@xxxxxx>
>Reply-To: stella@xxxxxxxxxxxxxxxxxx
>To: <stella@xxxxxxxxxxxxxxxxxx>
>Subject: Re: [stella] Games using unofficial opcodes
>Date: Thu, 2 Jun 2005 17:05:52 -0400
> > Emulator source code (Stella or Z26, not PCAE) will reveal most of what
> > you
> > need to know.  However, I have found that even these emulators don't do
> > all
> > of the exotic opcodes (in particular, neither seems to do RRA, which I
> > tried
> > to use in one of my games.)
>We have implemented all undocumented opcodes in z26 and tested them
>with Wolfgang Lorenz's C64 emulator test suite. So RRA should work
>properly. What happened when you tried to use RRA in z26 and what
>did you expect to happen? Also, which version of z26 did you use?
>Did your program work as expected on a real VCS?
>Ciao, Eckhard Stolberg
>Archives (includes files) at
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