Mike,Although you have likely already run across these by now, here are some possibly useful information sources.The panels SDK for MSFS has details of the proxy variables that allow you to read state. (At least the FS2K SDK did, haven't checked FS2K2). I know you're interested in input, but if you're building a full cockpit you'll have to drive lights and indicators as well.Peter Dowson maintains the FSUIPC freeware that interfaces to MSFS. The code and documentation are available at www.schiratti.com/dowson.html You mentioned "FS" and I have perhaps been wrong taking that to mean the Microsoft product. Certainly there are others. X-Plane, for example, can be interfaced to apparently fairly easily using UDP packets. See the X-Plane site www.x-plane.com and look under "Hacking X-Plane" for details.Mikewww.mikesflightdeck.comInfo for simpit builders

Hi Mike. Yep, Microsoft Flight Simulator. Yes, I'm interested in communicating both directions with the FS state machine. I think I have enough info to get started on the project now and by the way, it is not a home cockpit but a device to make hoem cockpit building easier.. Thanks for all the help.. MIke B.