RE: [stella] LXA illegal opcode?

Subject: RE: [stella] LXA illegal opcode?
From: "B. Watson" <atari@xxxxxxxxxxxxxx>
Date: Mon, 26 Jan 2004 21:02:57 -0500 (EST)

On Mon, 26 Jan 2004, Dennis Debro wrote:

> Hi Thomas,
> > Attached is that test program. Light blue means ok, dark brown means
> > error. Please try!
> Confirmed working on my 7800 and 4 switch via CC. Maybe Z26 might need
> another update.
> BTW, would you consider this a safe opcode? What if someone made a 2600 with
> a C64 6502? Is the 6502 in the C64 a stock product or is it a hybrid like
> the 6507 or 6502C (used in the A8)?

IIRC, it's a 6510, which is basically a custom part. I don't remember (if I
ever knew) whether anybody but Commodore ever used the 6510 for anything.

More interesting would be whether the LXA opcode is compatible with the
recently posted hack where someone replaced the 2600's 6507 with a 6502
and added 32K of RAM... My guess is yes, but it's a guess...

BTW, the test fails on the Stella emulator (not surprising).

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