I'm posting here a simple project to create an interrupt timer on an ESP32 board for version 3.1.1 by Esspressif Systems. I had difficulties to find updated information to make this code, I hope it can be useful to someone ! This code creates an interrupt every 100ms and counts the number of interr…

[image] RemiLNT: timer = timerBegin(1000000); // 1000000 µs = 100ms = 0.1s 1,000,000us is 1 second, not a 100ms [image] RemiLNT: I had difficulties to find updated information see this and this

Thank you, the comment was not on the right line. And thank you for the documentation, I couldn't find the documentation about the new version of eps32 by expressif

I would have at least a delay(2000) in the loop. [image] RemiLNT: while (1){ Serial.println("Erreur !!"); } An infinite loop() without an explicit yield(), delay() etc. may cause a watch dog timer reset which could make troubleshooting more complex. This comment is a bit mislead…

if I run your code on an ESP32 I get an exception - serial monitor output Start... E (20) gptimer: gptimer_start(396): timer is not ready for a new start if I replace your statement timerStart(timer); with timerAlarm(timer, 100000, true, 0); timer interrupt goes off every 100mSec - s…

[image] horace: if I run your code on an ESP32 I get an exception - serial monitor output Interesting. The OP's example looks close enough to the one here for the ESP32 Arduino 3.x core if that is indeed what you are running. Timer - - — Arduino ESP32 latest documentation

[image] 6v6gt: The OP's example looks close enough to the one here for the ESP32 Arduino 3.x core. I am using ESP32 core 3.1.1 think the problem is timerbegin() initializes the timer and starts it the following timerstart() attempts to start the timer again and throws the exception E (20) …

Ah yes. On looking more closely at the quoted official example, the statement timerStart(timer); does not appear. Actually, the error message you got is quite explicit and the behaviour of timerBegin() is also clear and documented to read "This function is used to configure the timer. After success…

[image] horace: I am using ESP32 core 3.1.1 FWIW, this code (originally written for Core 3.0.7) compiles and works in Core 3.1.1. So, any differences are not due to changes in the IDF APIs, but the Arduino APIs that wrap them. #include "Arduino.h" #include "driver/gptimer.h" void BlinkingTa…

the ESP32 timer is very useful by calling timerAlarm() in the timer ISR one can have a sequence of events of different periods, e.g. events at 100Usec 350uSec 750uSec // ESP32 timer interrupts - three pulses 100Usec 350uSec 750uSec #define pin 19 hw_timer_t *timer = NULL; // timer ISR invert …

[image] 6v6gt: An infinite loop() without an explicit yield(), delay() etc. may cause a watch dog timer reset which could make troubleshooting more complex. Thank you, I will correct that. Just a dalay(100); in the while{} ? [image] 6v6gt: If you are using the timer for only one purpose,…

Programming timer interruption

Projects Programming

b707 February 5, 2025, 4:09pm 2

1,000,000us is 1 second, not a 100ms

see this and this

Topic		Replies	Views
Timer Interrupt ESP32 Deutsch	8	641	August 16, 2025
ESP32 Timer Interrupt Frage Deutsch	5	817	April 9, 2024
Problema Interrupción Timer ESP32 Microcontroladores	2	191	May 29, 2025
ESP32 Timer Interrupt Programming	2	7642	June 11, 2024
Configuração de timer para ESP32 em IDE Arduino Português	2	178	November 5, 2025

Programming timer interruption

Related topics