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Button PollInterval for rotary encoder

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I'm trying to optimize the settings to get the fastest pulse rate that still works reliably for my rotary encoders:

The encoders send joystick button presses (one button for clock-wise, another one for counter-clock-wise). I have them assigned to "Vor1 Obi Inc/Dec" in fsuipc.

Basically, I have two parameters to tune (as far as I know):

  • Pulse width: Time the button stays pressed for each 'click' of the encoder. I can change this in the firmware.
  • The PollInterval setting in fsuipc.ini

I've tried setting pulse width to 20ms and the pollinterval to 5, but I'm losing clicks. 40ms pulses with 5ms polling works fine, but it takes ages to turn the OBI like that.

The strange thing is that, even with 10ms pulses, the FSUIPC menu still detects them reliably. The "Buttons+Switches" page reacts without fault. But when I assign them to controls, the pollinterval seems to be significantly longer.

Am I doing something wrong here?

edit: I should probably add that this is in P3D v3



Edited by scm@smurn.org
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Program both "press" and "release" for the same controls. That's the most you can do. Each click is either a press or a release. The default poll interval should be sufficient. Any other delay is down to the processing in the gauges, or whatever is processing the controls.



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Thanks Pete.

I'll guess I'll go with plan B then: Use a separate application to listen to the joystick buttons and then update the fsuipc offsets every 100ms or so, combining all clicks inbetween into one fsuipc write.

I've changed the firmware to toggle the buttons instead of a press & release cycle per click, as you suggest. I quick proof of concept shows that I can handle almost a 1000 clicks per second with an external application. That should be enough for even the most vigorous knob spinning :-)

Guess I have some programming to do this weekend....

Thanks for your help,




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