Egoruch / ESP32-TIM-INT-ARDUINO

Simple ESP32 Hardware Timer Interrupt with tests using frequency counter and oscilloscope

ESP32-TIM-INT-ARDUINO

Simple ESP32 Hardware Timer Interrupt with tests using frequency counter and oscilloscope

• Article (EN): https://refcircuit.com/articles/857-simple-timer-interrupt-esp32-s3-arduino-work-example.html

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• ESP32-S3 N16R8 (tested on)
• Arduino IDE 2.3.3 (tested on)
• Arduino ESP32 3.0.1 (tested on)

Arduino Configurations

Check Flash Size of your board (in my case it's 16MB). Enable USB CDC is you're use it for flashing and debbuging.

How to set frequency?

The final equation is here (obviously ESP32 has limitations, so you can't use any numbers):

$$f_{TIM} = \frac{TIM_{FREQ}}{TIM_{PER}} = \frac{1000000}{200} = 5000 Hz = 5 kHz$$

timer = timerBegin(1000000); // TIM_FREQ
timerAttachInterrupt(timer, &onTimer);
timerAlarm(timer, 200, true, ); // TIM_PER

Tests

The period of the generated signal will be twice bigger (2200 us=400 us) than actual timer interrupt frequency because we make pin toggle each time when we enter the handler.

Connection

Frequency Counter

Oscillosope