Proper way to control engines (programmatically)

[lordofwings]

Let's consider this scenario: I have a SAITEK Throttle Quadrant and my application is connected to FSX. Now, the two leftmost leversl of the TQ are in their middle position (i.e. not idle). Then how would I go about controlling the engine's throttles without having the TQ override my input?

In other words, if the Throttles on the TQ are at any position, I would expect that if my FSUIPC application writes any value to the throttle setting (say I write 0 for IDLE) then the Flight Simulator will immediately set it and subsequently read the current position of the levers of the TQ and directly obliterate the values I just wrote.

How do I manage that sitution?

My same question is valid for items such as the Mixture and Propeller levers.

[Pete Dowson]

In other words, if the Throttles on the TQ are at any position, I would expect that if my FSUIPC application writes any value to the throttle setting (say I write 0 for IDLE) then the Flight Simulator will immediately set it and subsequently read the current position of the levers of the TQ and directly obliterate the values I just wrote.

How are you writing those values?

I'm assuming you'd be assigning the throttles in FSUIPC rather than FS.

FSUIPC (and even FS) only make changes if they receive a new value. Providing your throttle is not moved and isn't jittering then it won't interfere. However, Saitek throttles in particular seem to be very jittery, so for this to work you probably would need to park them someplace calibrated as a dead zone. Alternatively most analogue input methods are usually stable at their very maximum and minimum positions -- which should really be calibrated with a little dead zone in any case.

If you are talking about some sort of fly-by-wire or external autothrottle implementation, though, and interfacing to FSUIPC via the offsets, please look up offset 310A which tells you how to do such things with the throttle inputs disconnected.

My same question is valid for items such as the Mixture and Propeller levers.

Really? So not fly-by-wire or autothrottle then? For those axes you'd need to park the levers into a stable or dead zone. If you wanted to disconnect them instead you'd need to use a Lua plug-in and route the values through that so they can be stopped. Easy enough, though. You could do the same with the thottles if you wished.

Regards

Pete

[lordofwings]

Thanks, as you supposed I was talking about using FSUIPC to write the values (using the FSUIPC C# SDK from Paul Hentty).