From your earlier picture LK90 is unpopulated. It's not on the original A3000 PCB, it's been added to allow Flash chips (like 39sf040) to be used for the OS. It feeds pin 1 of the rom sockets with +5V (2-3) or LA20 (1-2).
It probably won't matter with mask roms, like you have, but I'd still fit it and put a jumper on pins 2 & 3.
It probably won't matter with mask roms, like you have, but I'd still fit it and put a jumper on pins 2 & 3.
Statistics: Posted by IanS — Sun Aug 18, 2024 1:45 pm