servo.write(pin, value) doesn't produce expected PWM output

[kirbyny]

Testing environment is Arduino Nano ESP32 (S3), IDE 2.2.1 Attached scope trace taken using GPIO 6, but other GPIO produce same results.

myservo.write(pin, 500);  //produces 5738μs pulse width, expecting ~500μs - see scope trace
myservo.write(pin, 180); //produces 2400μs pulse width, expecting ~2500μs
myservo.write(pin, 0); //produces 544μs pulse width, expecting ~500μs

I'm assuming that I'm mis-reading the docs and simply doing something wrong here.

[kirbyny]

After looking at the source, it appears that PWM values I am seeing are the result of the channel data defined in pwmWrite.h.
Modifying these values produces the expected PMW values.

I am unsure where the original 5.7ms value came from, though changing the values shown below has eliminated the issue. Requesting a value lower than servoMinUs now outputs 2.5ms, though this seems counterintuitive (I would expect it to substitute .5ms rather than 2.5ms).

original code

`    mem_t mem[16] = {  // channel data (see above)
      {255, 1000, 0, 8, 0, 0, 0, 544, 2400, 0, 0, 0, 0, 0, 0, 0, 1.0, 0, 0},
      {255, 1000, 0, 8, 0, 0, 0, 544, 2400, 0, 0, 0, 0, 0, 0, 0, 1.0, 0, 0},
      {255, 1000, 0, 8, 0, 1, 0, 544, 2400, 0, 0, 0, 0, 0, 0, 0, 1.0, 0, 0},
      {255, 1000, 0, 8, 0, 1, 0, 544, 2400, 0, 0, 0, 0, 0, 0, 0, 1.0, 0, 0},
      {255, 1000, 0, 8, 0, 2, 0, 544, 2400, 0, 0, 0, 0, 0, 0, 0, 1.0, 0, 0},
      {255, 1000, 0, 8, 0, 2, 0, 544, 2400, 0, 0, 0, 0, 0, 0, 0, 1.0, 0, 0},
      {255, 1000, 0, 8, 0, 3, 0, 544, 2400, 0, 0, 0, 0, 0, 0, 0, 1.0, 0, 0},
      {255, 1000, 0, 8, 0, 3, 0, 544, 2400, 0, 0, 0, 0, 0, 0, 0, 1.0, 0, 0},
      {255, 1000, 0, 8, 1, 0, 0, 544, 2400, 0, 0, 0, 0, 0, 0, 0, 1.0, 0, 0},
      {255, 1000, 0, 8, 1, 0, 0, 544, 2400, 0, 0, 0, 0, 0, 0, 0, 1.0, 0, 0},
      {255, 1000, 0, 8, 1, 1, 0, 544, 2400, 0, 0, 0, 0, 0, 0, 0, 1.0, 0, 0},
      {255, 1000, 0, 8, 1, 1, 0, 544, 2400, 0, 0, 0, 0, 0, 0, 0, 1.0, 0, 0},
      {255, 1000, 0, 8, 1, 2, 0, 544, 2400, 0, 0, 0, 0, 0, 0, 0, 1.0, 0, 0},
      {255, 1000, 0, 8, 1, 2, 0, 544, 2400, 0, 0, 0, 0, 0, 0, 0, 1.0, 0, 0},
      {255, 1000, 0, 8, 1, 3, 0, 544, 2400, 0, 0, 0, 0, 0, 0, 0, 1.0, 0, 0},
      {255, 1000, 0, 8, 1, 3, 0, 544, 2400, 0, 0, 0, 0, 0, 0, 0, 1.0, 0, 0}
    };`

modified code

    mem_t mem[16] = {  // channel data (see above)
      {255, 1000, 0, 8, 0, 0, 0, 500, 2500, 0, 0, 0, 0, 0, 0, 0, 1.0, 0, 0},
      {255, 1000, 0, 8, 0, 0, 0, 500, 2500, 0, 0, 0, 0, 0, 0, 0, 1.0, 0, 0},
      {255, 1000, 0, 8, 0, 1, 0, 500, 2500, 0, 0, 0, 0, 0, 0, 0, 1.0, 0, 0},
      {255, 1000, 0, 8, 0, 1, 0, 500, 2500, 0, 0, 0, 0, 0, 0, 0, 1.0, 0, 0},
      {255, 1000, 0, 8, 0, 2, 0, 500, 2500, 0, 0, 0, 0, 0, 0, 0, 1.0, 0, 0},
      {255, 1000, 0, 8, 0, 2, 0, 500, 2500, 0, 0, 0, 0, 0, 0, 0, 1.0, 0, 0},
      {255, 1000, 0, 8, 0, 3, 0, 500, 2500, 0, 0, 0, 0, 0, 0, 0, 1.0, 0, 0},
      {255, 1000, 0, 8, 0, 3, 0, 500, 2500, 0, 0, 0, 0, 0, 0, 0, 1.0, 0, 0},
      {255, 1000, 0, 8, 1, 0, 0, 500, 2500, 0, 0, 0, 0, 0, 0, 0, 1.0, 0, 0},
      {255, 1000, 0, 8, 1, 0, 0, 500, 2500, 0, 0, 0, 0, 0, 0, 0, 1.0, 0, 0},
      {255, 1000, 0, 8, 1, 1, 0, 500, 2500, 0, 0, 0, 0, 0, 0, 0, 1.0, 0, 0},
      {255, 1000, 0, 8, 1, 1, 0, 500, 2500, 0, 0, 0, 0, 0, 0, 0, 1.0, 0, 0},
      {255, 1000, 0, 8, 1, 2, 0, 500, 2500, 0, 0, 0, 0, 0, 0, 0, 1.0, 0, 0},
      {255, 1000, 0, 8, 1, 2, 0, 500, 2500, 0, 0, 0, 0, 0, 0, 0, 1.0, 0, 0},
      {255, 1000, 0, 8, 1, 3, 0, 500, 2500, 0, 0, 0, 0, 0, 0, 0, 1.0, 0, 0},
      {255, 1000, 0, 8, 1, 3, 0, 500, 2500, 0, 0, 0, 0, 0, 0, 0, 1.0, 0, 0}
    };

Are the values of 544/2400 non-arbitrary?