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ESP32TimerInterrupt Simple Example

Here’s a stripped down example of Khoi¬†Hoang’s ESP32TimerInterrupt library. The library claims to run up to 16 compares (or alarms) on one, single timer. It seems to work well although I’ve only tested 3 timers thus far. I plan to use it on my Idiot Christmas Light Controller controlling triacs.

include <Arduino.h>
 /
   TimerInterruptTest.ino
   For ESP32 boards
   Written by Khoi Hoang
 Built by Khoi Hoang https://github.com/khoih-prog/ESP32TimerInterrupt
   Licensed under MIT license
 This is the most basic example using Khoi Hoang's ESP32TimerInterrupt library.  
   The library works well, but I found myself wanting an ultra basic version to understand the functionality
 */
 define TIMER_INTERRUPT_DEBUG 0
 define TIMERINTERRUPT_LOGLEVEL 0
 include "ESP32TimerInterrupt.h"
 // Change these to whatever GPIO you'd like to toggle
 define LED0 25 // GPIO 25
 define LED1 27 // GPIO 27
 define LED2 33 // GPIO 33
 // The lenght of each timer in milliseconds
 define TIMER0_INTERVAL_MS 100
 define TIMER1_INTERVAL_MS 3000
 define TIMER2_INTERVAL_MS 400
 void IRAM_ATTR TimerHandler0(void)
 {
   static bool toggle0 = false;
 //timer interrupt toggles pin LED0
   digitalWrite(LED0, toggle0);
   toggle0 = !toggle0;
 }
 void IRAM_ATTR TimerHandler1(void)
 {
   static bool toggle1 = false;
 //timer interrupt toggles LED1
   digitalWrite(LED1, toggle1);
   toggle1 = !toggle1;
 }
 void IRAM_ATTR TimerHandler2(void)
 {
   static bool toggle2 = false;
 //timer interrupt toggles LED2
   digitalWrite(LED2, toggle2);
   toggle2 = !toggle2;
 }
 // Init ESP32 timer 0,1, and 2
 ESP32Timer ITimer0(0);
 ESP32Timer ITimer1(1);
 ESP32Timer ITimer2(2);
 void setup()
 {
 pinMode(LED0, OUTPUT);
   pinMode(LED1, OUTPUT);
   pinMode(LED2, OUTPUT);
 Serial.begin(115200);
   while (!Serial)
     ;
 delay(100);
 Serial.print(F("\nStarting TimerInterruptTest on "));
   Serial.println(ARDUINO_BOARD);
 Serial.println(ESP32_TIMER_INTERRUPT_VERSION);
 Serial.print(F("CPU Frequency = "));
   Serial.print(F_CPU / 1000000);
   Serial.println(F(" MHz"));
 // Using ESP32  => 80 / 160 / 240MHz CPU clock ,
   // For 64-bit timer counter
   // For 16-bit timer prescaler up to 1024
 // Setup Timer0
   // Interval in microsecs
   if (ITimer0.attachInterruptInterval(TIMER0_INTERVAL_MS * 1000, TimerHandler0))
   {
     Serial.print(F("Starting  ITimer0 OK, millis() = "));
     Serial.println(millis());
   }
   else
     Serial.println(F("Can't set ITimer0. Select another freq. or timer"));
 // Setup Timer1
   // Interval in microsecs
   if (ITimer1.attachInterruptInterval(TIMER1_INTERVAL_MS * 1000, TimerHandler1))
   {
     Serial.print(F("Starting  ITimer1 OK, millis() = "));
     Serial.println(millis());
   }
   else
     Serial.println(F("Can't set ITimer1. Select another freq. or timer"));
 // Setup Timer2
   // Interval in microsecs
   if (ITimer2.attachInterruptInterval(TIMER2_INTERVAL_MS * 1000, TimerHandler2))
   {
     Serial.print(F("Starting  ITimer2 OK, millis() = "));
     Serial.println(millis());
   }
   else
     Serial.println(F("Can't set ITimer1. Select another freq. or timer"));
 Serial.flush();
 }
 void loop()
 {
 }
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