Re: 6502/6510 ROM selection daughterboard

From: Ingo Korb <>
Date: Sun, 03 Jun 2012 19:38:27 +0200
Message-ID: <>
Michał Pleban <> writes:

> I was thinking of another approach - a 6502 running side by side on the
> cartridge, executing the same code as the main CPU. IIRC, 6502 and 6510
> are cycle-compatible, so this could be done easily. So one could easily
> detect writes to $01 and set the flags appropriately without playing
> crudely with the PLA lines.

You can't see the results of reads from $00/$01, so tape accesses and
anything that tries to detect the bit fading on the top two bits of $01
will throw you off.


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Received on 2012-06-03 18:00:27

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