It has a 25-pin serial port which converts to a 9-pin serial port by a simple passive converter (basically, just ditch 16 of the pins and route the others prope

It has a 25-pin serial port which converts to a 9-pin serial port by a simple passive converter (basically, just ditch 16 of the pins and route the others properly, you can actually do serial with just two wires). Same goes for the ADM-3a