Quote Originally Posted by starmarky View Post
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It is not clever to connect the LED directly to the switch because the FD could go off due to other events in the cockpit without any switching of the knob. So the FD-status for the LED has to come directly from the offset, not from the switch position.
Exactlly! That is also the reason why one should not combine a control and a state in one and the same offset.

A good example, of how one should interface, is the Level-D SDK, in there you will find control commands for switches, and separate state variables for the position of a switch.
Take for instance a Korry Switch, that one has even two states, the position of the switch (On/Off) and an indicator whether the function controlled by the switch works or not (see for instance the 'press' light in Fuel Pump korries)

regards,
Nico