Re: Hardware emulation of 6509 using 6502?

From: smf <*smf_at_null.net*> Date: Fri, 2 Mar 2018 21:38:52 +0000 Message-ID: <57feebca-d1d1-a486-1e17-7e17e26f5568@null.net> · smf_at_null.net

On 02/03/2018 12:44, Michał Pleban wrote:
> The P500 has SRAM in bank F just like the 610, so I think it could work.
> At least it's an idea worth a quick check (assuming that Jim has a P500?)

The interaction between dram and vic2 is where it gets interesting as 
I'm not sure the vic2 can see the sram at $0/$1 in bank f. Even I'm not 
sure I'd worth worrying about writing to ram that neither the cpu or 
vic2 could read.

But letting the data lines float during $0/$1 writes is necessary & then 
you get the functionality for reads for free.

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