I already checked cas/ras and they were there, as was power. I may have also checked the address pins, but my memory escapes me. It often does these days.......stephen_usher wrote: ↑Sat Jun 12, 2021 3:53 pm Yeah. It's always good to check. Maybe check what signals the RAM chip is getting from the ULA whilst you have the socket there and maybe buzz out the data path to the ULA. (Being paranoid.)
I need to try and make up a pinout diagram for the ULA as the pins, other than 1 on my glop top soldered in model, are not at all clear. I only know where pin 49 is as I checked the 16Mhz clock there.