PWM output on 2.0.42

Hi,I measured a PWM output on sparkfun ATmega1280 and I found that when system is not armed all pwm outputs are 50 Hz, 1 ms, when I arm the system I experienced a variable frequency pwm output form 200 Hz to 300 Hz with duty cycle depending on the radio command. Is that normal? ThanksAngelo

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  • (Having looked at the implementation in APM_RC.cpp) Why isn't the timer/counter's 'TOP' value just reduced to 5000 rather than having that 'Force_Out0_Out1' jazz?  Manipulating the timer/counter register to 'skip' over part of the timing seems unnecessary and terrifying.

  • ESCs dont typically use a clock pulse for sync so can take any frequency upto (i believe) 450hz ish. After that the 2ms maximum pulse width begins to blend into a constant high.
  • Instant PWM? Oscilloscope correctly captured the signal with a variable frequency. Are the ESC capable of decoding such signal?
  • Developer

    Yeah, that's "Instant PWM" kicking in.

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