UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post - Non-working Commodore PET 3016

Mark1960 · 2nd Mar 2021, 5:25 pm

I think it would be good to check the data lines again with the duff prom replaced, see if DA0 is still showing low logic levels from one or more proms.

You could try first with the 6502 direct connected, but its not running NOP now so the pattern will be different and you might not be getting chip select on every prom now.

2nd Mar 2021, 5:25 pm	#750
Mark1960 Octode Join Date: Mar 2020 Location: Kitchener, Ontario, Canada Posts: 1,298	Re: Non-working Commodore PET 3016 I think it would be good to check the data lines again with the duff prom replaced, see if DA0 is still showing low logic levels from one or more proms. You could try first with the 6502 direct connected, but its not running NOP now so the pattern will be different and you might not be getting chip select on every prom now.