Integrating BFF Control Loading Boards with Jeehell FMGS [Lua]

The BFF control loading board can now be directly interfaced with Jeehell with the help of Lua scripting (FSUIPC registered version required).

BFF Control Loading Boards 3-Axis system; only one board is required for Airbus rudder control

In the simulator setup, the BFF control loading board connects to a motor attached to a shaft which moves the rudder pedals. The system allows for rudder auto spring resistance (centering), and rudder trimming. This is useful if OEI (one engine inoperable) scenarios need to be simulated as the BFF Control Loading (CL) software can detect asynchronous engine thrust, and auto-trim the rudder system.

The BFF CL boards are an affordable and cost effective way to integrate control loading (“force feedback”) into your simulator (more information on the Soarbywire setup here).

To setup the boards with Jeehell FMGS, autopilot annunciator offsets (AP1, AP2) must be exported to a custom offset so the BFF CL can detect that the aircraft has autopilot enabled.

This can be implemented with the following Lua script:


– Log Jeehell FMGS AP1 & AP2 LED outputs to offset 0x5300

function autopilot(offset, value)
—    ipc.log(“**** autopilot lua: value received = ” .. value)
if value == 0 then — both AP’s are off
else — at least one AP is on

event.offsetmask(0x7390, 3, “UB”, “autopilot”)

ipc.log(“Jeehell FMGS AP1 & AP2 LED outputs lua started”)

Simply place the script in your /documents/Prepar3D Add-ons/FSUIPC folder and add the line ‘1=Lua Jeehell_AP’ in the [AUTO] section of fsuipc.ini

Other practical uses of the Lua script is that it can export to a offset (gate), and it can trigger a relay powering the sidestick solenoids when either AP1, AP2 or both are enabled (sidestick lock).

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