ACU Romboard (DIY)
A DIY project to make a romboard
ROM Selection is made using a port decoded with A13=0, A14=1. D3 must be 0, D2..D0 select the ROM, allowing up to 8 ROMs to be selected, but the PCB only has 6 EPROM sockets. Sockets for ROM 0 and ROM 7 aren't fitted. More than one value can select the same ROM (e.g. &11 will also select &1).