Servo control on ESP32

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One of the things that do not work the Arduino way in the ESP32 so far is the PWM generation using analogWrite() command. There is, however, a library to handle PWM signals using timers, so up to 16 PWM signals can be handled.  You can find fine examples like this one.

However, I wanted to use timers in my project and I wanted to have a clearer view of what was going on, so I decided to handle the PWM timing myself. Here you have an example of how to handle a single servo using a timer. Same timer and routine could be extended to handle more output pins in a similar fashion, but I just needed one here.


It is just a simple sketch that moves the servo back and forth using a sin function to get this motion easily, ranging the signal pulse width from 600 to 2200 microseconds.

This is the end result:



All in all, I am impressed with the simplicity and power of the ESP32 and the great Arduino-esp32 code. Kudos to Espressif.

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