I have successfully managed to get FSX, Link2FS and my Arduino Uno talking and have now spent many hours watching my landing gear go up and down and my "three greens" turn on and off (Actually they are yellow but I'm sure we all remember this first success !!)

I'm part way through building a composite MCP for my simming. It is broadly based on the 737NGX MCP (for PMDG) though with some poetic license to allow for B747 and potentially Airbur as well. I've made the panel itself and have all the buttons in stalled. I'm currently working on the LED indication of which mode is active.

Having got the gear going up and down and indicating on a set of LEDs, I'm now struggling to understand how I read the status of the various MCP modes and can then pass them (using modified code) to my Arduino - e.g. CMD active, FLCH active, LOC capture active etc.

Any clues as to how I might read these values from FSX ? I think I can then get them into the Arduino OK from there.