[BBC-Micro] New 6502 second processors?

[Michael Firth]

Has anyone given any thought to producing replacement internal or external 6502 second processors?

It would seem that most of the design pieces exist (mostly on Sprow's website), and it shouldn't be an impossible task.

Given that any that appear on eBay are going for well over £50, and not that many appear, it seems there's a demand for them.

If anyone is thinking about it, would they go for an entirely virtual approach (using a 6502 core in a FPGA or similar), or a physical 6502?

To me, the parts list would only have to be (roughly):
2x 62256 RAM
1x 65C02 CPU
ULA replacement (presumably a PLD of some sort)
1x Oscillator
1x Small EPROM (existing boards have 2k)
Connectors, PSU etc.

I'm presuming that if a PLD is used to replace the ULA then it could also be used for the (fairly minimal) address decoding etc needed.

Am I missing something major from this list?

Michael
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