Hi All!

I have some SY6502 and 68A09 processors that I'm wanting to build into single board computers.

However, I don't know if any or all of them work. They're used pulls from various places so I don't know the history on them. I don't want to spend an inordinate amount of time only to find the processor is toast.

Is there a simple test circuit (short of a whole system) that could be rigged up for each of these processors to verify that they are functional?

Thanks

Gary

You could try Lee Davison's NOP generator. It will cycle through the 65k address space execuing the NOP instruction...this would at least verify that the CPU is getting the clock, reading the databus, and processing the NOP instruction.

Here's a link:
http://www.6502.org/mini-projects/nop-gen/nop-gen.htm

Daryl

Yeah, I saw that and thought I could probably just hook up the oscillator and rom socket and just use that to test it. I guess if the CPU was functioning, I'd see the address lines cycle. That would be good enough for a good/not good type of determination.

Anybody see any problems with this?

What about putting the 6502 in a working VIC-20? If it starts up, the 6502 is OK. Same for the 6809 (which should NOT be put in the VIC-20 of course :)

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