Re: [stella] Games using unofficial opcodes

Subject: Re: [stella] Games using unofficial opcodes
From: "Eckhard Stolberg" <Eckhard_Stolberg@xxxxxx>
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

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