esp32 timerbegin(0 80 true)

timer= timerBegin(0, 80, true); This function returns a pointer to a structure of type hw_timer_t, which we will define as the timer global variable. We pass three values to this function, the first one is the timer to use.

CircuitDigest

circuitdigest.com › microcontroller-projects › esp32-timers-and-timer-interrupts

ESP32 Timers & Timer Interrupt Tutorial

August 5, 2025 - void setup() { pinMode(LED, OUTPUT) My_timer = timerBegin(0, 80, true); timerAttachInterrupt(My_timer, &onTimer, true); timerAlarmWrite(My_timer, 1000000, true); timerAlarmEnable(My_timer); } void loop() { } And in the Setup function, we have initialised GPIO21 as an output with the help of the pinMode macro. ... To initialise the timer, we are using the ESP32 timerBegin function with the following variables.

Discussions

Hardware timer, how to run once and restart again?

I had some trouble with timers and alarms on my esp32 doit devboard. Spent many hours trying to debug, end of the days its a silicon issue with the REV0 chips. Not sure if this applies to you but more information can be found here: https://github.com/espressif/arduino-esp32/issues/1313 More on reddit.com

r/esp32

8

5

April 12, 2021

ESP32 Timer Interrupt

Hi Folks, I am using Esp32 Dev Module to develop the timer interrupt code .but when I am using timerBegin() function I am getting errors like that: timerBegin() function can accept only one argument.Please help me out this problem.For you reference I am posting my code. More on forum.arduino.cc

forum.arduino.cc

2

0

June 10, 2024

Problema con timer y gestor de placa ESP32

En la version 2.x (gestor de placa de esp32 de espressif systems) la configuración de los timers por ejemplo "timer = timerBegin(1,80,true);" te permite elegir el timer en este caso timer1 pero en la version 3.x solo se ingresa la frecuencia ejemplo "timer = timerBegin(1000000);" entonces ... More on forum.arduino.cc

forum.arduino.cc

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July 20, 2024

Timer error building infinity cube. New syntax?

That library hasn't been updated for Arduino 3.0. This is the old way to make timers: prescaler=80000000/frequency; timer = timerBegin(0, prescaler , true); timerAttachInterrupt(timer, &onTick, true); timerAlarmWrite(timer, 1, true); timerAlarmEnable(timer); and this is the new way, where 'frequency' is in Hz. timer = timerBegin(frequency); timerAttachInterrupt(timer, &onTick); timerAlarm(timer, 1, true, 0); More on reddit.com

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11

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June 8, 2025

DeepBlue

deepbluembedded.com › home › blog › esp32 timers & timer interrupt tutorial (arduino ide)

ESP32 Timers & Timer Interrupt Tutorial (Arduino IDE) – DeepBlueMbedded

February 17, 2025 - Typical compile error message is now…. error: too many arguments to function ‘hw_timer_t* timerBegin(uint32_t)’ 159 | Timer0_Cfg = timerBegin(0, 8, true); // timer 0, 80MHz/8 = 10MHz = 0.1us/tick

Mechatronics LAB

mechatronicslab.net › home › lessons › esp32 arduino programming handbook › chapter 12: timers, delays & interrupts › timers for esp32 arduino programming

Timers for ESP32 Arduino Programming - Mechatronics LAB

Syntax · hw_timer_t *timer = NULL; ... true); // 1 second timerAlarmEnable(timer); // start timer } Syntax Explanation timerBegin(0, 80, true) creates timer 0....

GitHub

gist.github.com › futureshocked › 5327bec254a9d5afcc91fa0b673442b6

ESP32 timer interrupts, how to change duration in the loop. · GitHub

Essa é a maneira recomendada de lidar com interrupções, especialmente em plataformas sensíveis ao tempo como o ESP32. Isso evita problemas com watchdog timers e garante que a ISR seja o mais rápida e leve possível.

Espressif Docs

espressif-docs.readthedocs-hosted.com › projects › arduino-esp32 › en › latest › api › timer.html

Timer — Arduino-ESP32 2.0.14 documentation

#include "esp_system.h" #include "rom/ets_sys.h" const int button = 0; //gpio to use to trigger delay const int wdtTimeout = 3000; //time in ms to trigger the watchdog hw_timer_t * timer = NULL; void ARDUINO_ISR_ATTR resetModule() { ets_printf("reboot\n"); esp_restart(); } void setup() { Serial.begin(115200); Serial.println(); Serial.println("running setup"); pinMode(button, INPUT_PULLUP); //init control pin timer = timerBegin(1000000); //timer 1Mhz resolution timerAttachInterrupt(timer, &resetModule); //attach callback timerAlarm(timer, wdtTimeout * 1000, false, 0); //set time in us } void lo

Phatiphat Thounthong

phatiphatt.wordpress.com › esp32-sampling_mode

ESP32 Timer Interrupt (Sampling Mode) – Phatiphat Thounthong

October 21, 2020 - Total number: “); Serial.pri... pinMode(LED1, OUTPUT); //Step #1 My_timer = timerBegin(0, 80, true); //Name = timerBegin(timerN, prescale, up/down); //count up (true) or down (false)....

Vb-electronics

vb-electronics.github.io › Esp32-101-board › Notes › ESP32-TIMER › ESP32-TIMER

ESP32-TIMER - Esp32-101-board

#include "C:\Users\KolevBM\AppData\Local\Arduino15\packages\esp32\hardware\esp32\2.0.2\cores\esp32\esp32-hal-timer.h" #include "Arduino.h" volatile int interruptCounter; int totalInterruptCounter; hw_timer_t * timer = NULL; portMUX_TYPE timerMux = portMUX_INITIALIZER_UNLOCKED; void IRAM_ATTR onTimer() { portENTER_CRITICAL_ISR(&timerMux); interruptCounter++; portEXIT_CRITICAL_ISR(&timerMux); } void setup() { Serial.begin(115200); timer = timerBegin(0, 80, true); //from 0 to 3, since we have 4 hardware timers) timerAttachInterrupt(timer, &onTimer, true); timerAlarmWrite(timer, 1000000, true); timerAlarmEnable(timer); } void loop() { if (interruptCounter > 0) { portENTER_CRITICAL(&timerMux); interruptCounter--; portEXIT_CRITICAL(&timerMux); totalInterruptCounter++; Serial.print("An interrupt as occurred.

ESP32 Forum

esp32.com › viewtopic.php

Timers and interrupts not working as expected - ESP32 Forum

January 12, 2024 - hw_timer_t * timer = NULL; void IRAM_ATTR onTimer() { bool state = digitalRead(5); digitalWrite(5, !state); } void setup() { pinMode(5, OUTPUT); Serial.begin(115200); timer = timerBegin(0, 80, true); // Timer 0, prescaler 80, count up timerAttachInterrupt(timer, &onTimer, true); timerAlarm...

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Luis Llamas

luisllamas.es › inicio › tutoriales arduino › curso esp8266 / esp32

How to use ESP32 timers

November 25, 2024 - Below is an example of how to use ... = true; } void setup() { Serial.begin(9600); pinMode(LED_BUILTIN, OUTPUT); timer = timerBegin(0, 80, true); // Timer 0, clock divisor 80 timerAttachInterrupt(timer, &timerInterrupt, true); ...

ESP32 Forum

esp32.com › viewtopic.php

ESP32 Timer Problem - ESP32 Forum

April 1, 2022 - timer0 = timerBegin(0, 80, true); //timer 0, div 80 · timerAttachInterrupt(timer0, &resetModule0, true); //attach callback · timerAlarmWrite(timer0, wdtTimeout * 1000, false); //set time in us · timer1 = timerBegin(1, 80, true); //timer 0, div 80 · timerAttachInterrupt(timer1, &resetModule1, ...

Espressif

docs.espressif.com › projects › arduino-esp32 › en › latest › api › timer.html

Timer - - — Arduino ESP32 latest documentation

#include <Arduino.h> #include "esp_system.h" #include "rom/ets_sys.h" const int button = 0; //gpio to use to trigger delay const int wdtTimeout = 3000; //time in ms to trigger the watchdog hw_timer_t *timer = NULL; void ARDUINO_ISR_ATTR resetModule() { ets_printf("reboot\n"); esp_restart(); } void setup() { Serial.begin(115200); Serial.println(); Serial.println("running setup"); pinMode(button, INPUT_PULLUP); //init control pin timer = timerBegin(1000000); //timer 1Mhz resolution timerAttachInterrupt(timer, &resetModule); //attach callback timerAlarm(timer, wdtTimeout * 1000, false, 0); //set

ESP32 Forum

esp32.com › viewtopic.php

Converting 2.0.17 Timer code to 3.0+ - ESP32 Forum

I am attempting to upgrade some code written with the older Timer library for the esp32 2.17.0 Arduino library that looks something like this: ``` askRequestTimer = timerBegin(0, 80, true); timerAttachInterrupt(askRequestTimer, &onAskReqTimer, true); timerAlarmWrite(askRequestTimer, 5*1000000, ...

reddit.com › r/esp32 › hardware timer, how to run once and restart again?

r/esp32 on Reddit: Hardware timer, how to run once and restart again?

April 12, 2021 -

Guys

I have a DevKitC dev board, and I'm trying to set up a HW timer that I want to re-use under certain conditions. In other words, I don't want it to reload automatically, it should run once and then remain dormant until I enable it again. It seems to work the first time, but when I enable the timer a second time it fires immediately, without any delay. It seems I'm not resetting it properly, so that the counter starts from 0 again (?).

What I've tried is this:

initialize timer 0 in setup(), with a prescaler for 80MHz.

myTimer = timerBegin (0, 80, true);
timerAttachInterrupt (myTimer, &isrMyTimer, true);

then when I want to use the timer I enable it as follows (for a duration of 3 seconds):

timerAlarmWrite(myTimer, 3000000), false);
timerAlarmEnable(myTimer);

I am also trying to confirm the frequency to use for the timer, whether it is indeed 80MHz. I get the values as shown below for the different functions. Any thoughts on what they mean?

getCpuFrequencyMhz()		240	
getXtalFrequencyMhz()		40
getApbFrequency()		80000000

Top answer

1 of 4

2

I had some trouble with timers and alarms on my esp32 doit devboard. Spent many hours trying to debug, end of the days its a silicon issue with the REV0 chips. Not sure if this applies to you but more information can be found here: https://github.com/espressif/arduino-esp32/issues/1313

2 of 4

2

I managed to get it working. The trick that worked for me was to reset the timer (counter) before each use, with the following statement: timerRestart() Below is a little pseudo sketch, only showing the relevant statements, to give you or anyone finding this post later, an idea of what worked for me. #include // only needed to get ESP32 frequency detail hw_timer_t * tmrTEST = NULL; // timer used for TESTING unsigned long lngTimerStart = 0; // system micro-seconds at timer start int tmrDuration = 5; // run timer for 5 seconds // Interrupt Service Routine called when TEST timer fires. void IRAM_ATTR isrTimerTEST() { Serial.print(" >>>>> TEST TIMER ISR: "); Serial.print( micros() ); Serial.print(" diff="); Serial.println((micros()-lngTimerStart)/1000/1000); } void setup() { Serial.begin(115200); ... // Set up TEST timer.. tmrTEST = timerBegin (1, 80, true); // use ESP32 Timer 1, pre-scale 80 (for 80MHz freq), count up. timerAttachInterrupt (tmrTEST, &isrTimerTEST, true); // attach the function to call when timer interrupt fires. Edge. Serial.print(" >> CPU Freq: "); Serial.println(getCpuFrequencyMhz()); Serial.print(" >> XTL Freq: "); Serial.println(getXtalFrequencyMhz()); Serial.print(" >> APB Freq: "); Serial.println(getApbFrequency()); ... } void loop() { ... if (tmrDuration > 0) { // initiate TEST timer. duration in micro-seconds. False to run once. timerAlarmWrite(tmrTEST, (tmrDuration * 1000000), false); timerRestart(tmrTEST); // reset timer counter timerAlarmEnable(tmrTEST); // start the timer lngTimerStart = micros(); Serial.print(" >>>>> TimerTEST dur="); Serial.print(tmrDuration); Serial.print(" start: "); Serial.println( lngTimerStart ); } ... } Thanks for your replies and time !

Arduino Forum

forum.arduino.cc › projects › programming

ESP32 Timer Interrupt - Programming - Arduino Forum

June 10, 2024 - Hi Folks, I am using Esp32 Dev Module to develop the timer interrupt code .but when I am using timerBegin() function I am getting errors like that: timerBegin() function can accept only one argument.Please help me out this problem.For you reference I am posting my code.

QuadMeUp

blog.quadmeup.com › home › programming › esp32, arduino and timer/alerts

ESP32, Arduino and Timer/Alerts » QuadMeUp

May 20, 2025 - timer = timerBegin(0, 80, true); If you run ESP32 with a different clock, you have to modify the prescaler.

Arduino Forum

forum.arduino.cc › international › español › microcontroladores

Problema con timer y gestor de placa ESP32 - Microcontroladores - Arduino Forum

July 20, 2024 - En la version 2.x (gestor de placa de esp32 de espressif systems) la configuración de los timers por ejemplo "timer = timerBegin(1,80,true);" te permite elegir el timer en este caso timer1 pero en la version 3.x solo se …

reddit.com › r/esp32 › timer error building infinity cube. new syntax?

r/esp32 on Reddit: Timer error building infinity cube. New syntax?

June 8, 2025 -

Building, https://github.com/mecharms/Infinity-LED-CUBE/tree/main

I believe the problem is the timer is written under old format so does not work with new version in IDE.

Does anyone know if this is just a syntax fix?

 //--------------------------------
  // Configure Prescaler to 80, as our timer runs @ 80Mhz
  // Giving an output of 80,000,000 / 80 = 1,000,000 ticks / second
  timer = timerBegin(0, 80, true);                
  timerAttachInterrupt(timer, &onTime, true);    
  // Fire Interrupt every 1m ticks, so 1s
  timerAlarmWrite(timer, 5000000, true);      
  timerAlarmEnable(timer);
  //--------------------------------

C:\Users\Jason\Downloads\Infinity-LED-CUBE-main\Infinity-LED-CUBE-main\code\cube_led\cube_led.ino: In function 'void setup()':

C:\Users\Jason\Downloads\Infinity-LED-CUBE-main\Infinity-LED-CUBE-main\code\cube_led\cube_led.ino:3829:21: error: too many arguments to function 'hw_timer_t* timerBegin(uint32_t)'

3829 | timer = timerBegin(0, 80, true);

| ~~~~~~~~~~^~~~~~~~~~~~~

In file included from C:\Users\Jason\AppData\Local\Arduino15\packages\esp32\hardware\esp32\3.2.0\cores\esp32/esp32-hal.h:98,

from C:\Users\Jason\AppData\Local\Arduino15\packages\esp32\hardware\esp32\3.2.0\libraries\Wire\src/Wire.h:33,

from C:\Users\Jason\Downloads\Infinity-LED-CUBE-main\Infinity-LED-CUBE-main\code\cube_led\cube_led.ino:2:

C:\Users\Jason\AppData\Local\Arduino15\packages\esp32\hardware\esp32\3.2.0\cores\esp32/esp32-hal-timer.h:35:13: note: declared here

35 | hw_timer_t *timerBegin(uint32_t frequency);

| ^~~~~~~~~~

C:\Users\Jason\Downloads\Infinity-LED-CUBE-main\Infinity-LED-CUBE-main\code\cube_led\cube_led.ino:3830:23: error: too many arguments to function 'void timerAttachInterrupt(hw_timer_t*, void (*)())'

3830 | timerAttachInterrupt(timer, &onTime, true);

| ~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~

C:\Users\Jason\AppData\Local\Arduino15\packages\esp32\hardware\esp32\3.2.0\cores\esp32/esp32-hal-timer.h:50:6: note: declared here

50 | void timerAttachInterrupt(hw_timer_t *timer, void (*userFunc)(void));

| ^~~~~~~~~~~~~~~~~~~~

C:\Users\Jason\Downloads\Infinity-LED-CUBE-main\Infinity-LED-CUBE-main\code\cube_led\cube_led.ino:3832:3: error: 'timerAlarmWrite' was not declared in this scope; did you mean 'timerWrite'?

3832 | timerAlarmWrite(timer, 5000000, true);

| ^~~~~~~~~~~~~~~

| timerWrite

C:\Users\Jason\Downloads\Infinity-LED-CUBE-main\Infinity-LED-CUBE-main\code\cube_led\cube_led.ino:3833:3: error: 'timerAlarmEnable' was not declared in this scope; did you mean 'timerAlarm'?

3833 | timerAlarmEnable(timer);

| ^~~~~~~~~~~~~~~~

| timerAlarm

exit status 1

Compilation error: too many arguments to function 'hw_timer_t* timerBegin(uint32_t)'

Thank you!