Originally Posted by crazyc
Looks like the test mode pin is connected to the upd78p214 along with the serial port(?). Would be neat to make the networking work.

yeah, it seems the board had some sort of serial connection. its emulation is probably beyond my current set of skills, though (my frustration with MegaDrive serial EEPROMs exposed that I clearly suck at understanding serial comms from the running code), so if you want to take a look, the relevant slot device is at src/mess/machine/sns_event.c