[morcheeba]

Yep. The 65C02 has a SYNC output that goes high to indicate an instruction is being fetched on the current cycle. Since there is no cache, it's pretty simple to use this to determine the PC.

[ddingus]

Thought so. From there, it is a bit of logic to map the chip selects to make the writes and reads come and go from the intended resources.

[forinti]

That's it then. I was missing the sync pin. Thank you.