Re: [stella] LXA illegal opcode?

Subject: Re: [stella] LXA illegal opcode?
From: Thomas Jentzsch <tjentzsch@xxxxxx>
Date: Wed, 28 Jan 2004 19:45:50 +0100
Oliver Achten wrote:
> Perhaps the best solution is to stick to the C64 documentation and avoid
> unstable opcodes, since they seem to cause a malfunction in the 6502 bus
> circuit, leading to processing undefined byte values.

> Esapecially if you notice that the behaviour is strongly influenced by the
> electrical design of the bus.

I agree. I just checked again on my three PAL 2600s:
- Six Switcher: behaves like in the C64 documentation (ora #$ee)
- Darth Vader: like Dennis mentioned
- Chinese Jr: both don't work.

Let's just stick to the stable "illegal" opcodes.

Have fun!
Thomas Jentzsch         | *** Every bit is sacred ! ***
tjentzsch at web dot de |

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