Re: [stella] Games using unofficial opcodes

Subject: Re: [stella] Games using unofficial opcodes
From: Adam Wozniak <adam@xxxxxxxxxxxxxxxx>
Date: Wed, 1 Jun 2005 13:23:01 -0400
Hash: SHA1

On Wed, 1 Jun 2005, Dennis Debro wrote:
> I looked at this and I think it uses one by accident. It does a jmp to
> LF01F which would cause the sax (opcode $83) instruction to be called.
> They could have jmp'd to LF021 (which is the Veritcal Sync routine) which
> would have bypassed this and the game would have worked the same.

Is there a good complete opcode reference that includes all the undocumented
pro: discusses undocumented opcodes
con: difficult to search, doesn't list status flags affected succinctly
pro: hyperlinks for easy navigation
con: no undocumented opcodes, doesn't list status flags affected succinctly
pro: lists alternate names for undocumented opcodes
con: doesn't list status flags affected succinctly
pro: big chart has lots of information
con: difficult to read, doesn't list status flags succinctly
pro: nice charts, status flags affected are listed
con: descriptions are terse, unclear which opcodes are not available on 6502
pro: nice charts, nice explanation of how opcodes are decoded
con: few english descriptions

Is there a web page somewhere that combines the best of all these?
One geared for atari 2600 programmers?

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