Re: Dataman Microdoctor
We looked at the idea of doing something like this with an Arduino Mega in ScottishColin's PET repair but the situation there was complicated by the fact that the system had dynamic RAM and all the timing for that was derived from the 'clock 2' output on the 6502, so the Arduino impostor would have had to try to generate all needed signals with the correct relative timing, even if it drove the whole thing in slo-mo - but not too slow, because otherwise it might have failed to refresh the RAM in time.
That, and the lack of a similar system for me to try it in myself first, was the main reason we didn't attempt it and in the end made the necessary diagnois by running test code kindly provided by Slothie and Daver2 on the machine itself, something it was fortunately able to do.
Trying to do it with an Arduino would have generated more questions than answers, most likely. You'd have to get a system like that working on a definitely known working host system and producing sensible results from that first before then trying to use it on a broken system.
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