FDT
Interfacing was first done with Flight Deck Technology cards which provided 32 inputs and 32 outputs. These boards can deal with toggle switches without the need to construct pulse circuits or use relays. They check the position of switches at startup and set the sim to the switches condition.
Most of the switches and lights on the Flight Guidance Computer are operated by a Go Flight auto pilot RMK. The switches and lights that are not included in the Go Flight unit will operated by the FDT boards.
BU0836X
Leo Bodnars boards are also used in the centre pedestal to operate the throttles, flaps and spoilers and also the switches in the fuel panel. The illumination of the switches, which are double pole, is from a small 240v to 6v power supply. A bit of logic in set up in the switch arrangement in that you cannot operate a starter switch without the appropriate ignition switch on. The fire switches which are not quite Lear Jet (I had two missile covers and just had to use them), are set to cut the fuel pump to each engine.
I have also used another of Leo’s boards for the radio units. Using FSUIPS to send a key stroke to the Reality XP gauge and also operating two rotary encoders for tuning.