Hi all, 

i'm interested on how the current code (3.1-dev) uses the free output pin in the case we want to use them for controlling standard servo or a shutter.

I fly a quad and i've compiled the 3.1-dev from eclipse. I've tried to set the the PWM frequency to 50hz from MP before connecting a servo to CH5 and then in MP selecting CH5 for roll stab.

This works, servo moves correctly.  (and i imagine that the other channel, CH6-CH8 in MP, are connected to the CH6-8 output).

So now i've tried putting PWM freq to 50hz to save a servo, but what happens to this output (CH5-8) in quad configuration IF i put the PMW frequency back to 490hz? They will ouput 490hz or in a quad configuration automatically they works a 50hz?

So, i'm not a good coder, but analyzing laserlab_MP32V1F4.cpp , lines from 12 to 33, seems to be what i'm looking for but they are commented and a big warnig says that the TIMER change can be done only if the receiver is connected in PPMSUM.

So what i've understood is: You have to use PPMSUM in order to get 50hz on the free CH5-8 output (in quad mode).

Is that right?

Best Regards

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  • Hello, if you get the latest version from git the 490Hz update frequency is set only for motors used in your configuration.

    So if you have a quad only CH1 to CH4 will output at 490Hz.

    All other OUTPUT channels will be 50Hz as default.

    This is a fairly recent update because before all outputs CH1 to CH6 were at 490Hz. So please get latest version.

    When connecting PPMSUM, we have actually 4 INPUTS free that can be used as inputs/outputs, but at the time writing we still need to correctly manage the freed pins to be of general purpose IO.

    If you tell me what you would like to achieve, we could work together to get something done.



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