Here is a picture of the custom driver boards
Starting from the left is the lamp drivers, then the coil drivers, then what I call special drivers (flipper on/off relay, GI on/off relay and other cabinet lamp drivers. The last board is a parallel port interface board. It uses 4 bit to 16 line decoders which lets me drive 16 lamps, 16 coils and 4 other special lines.
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