JC8080
Well-known member
I checked pin 82 of the MDU (shown as /ROMOE on the developer notes, and ROM SEL on the Bomarc schematics), it starts high and stays high. I also checked a couple address and data lines, all started high and stayed high, though admittedly I am not exactly sure what you should see on a address/data line.Check for chip enable on the ROM chips. There is crud around W1?
Check for bad traces around C34. Not only the nearby transistors/diodes, but also the CPU pins around 50/51.
This weekend hopefully I will have time to take a closer look for broken traces under a microscope, and also R&R the chips @imactheknife pointed out.