ESP32_multiple_timers_experiment.ino

/* 
  orginal code via: 

 * Copyright (c) 2017 pcbreflux. All Rights Reserved.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, version 3.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>. *
 * 
 
  modified by @kosso
 
 */
hw_timer_t * timer0 = NULL;
hw_timer_t * timer1 = NULL;
portMUX_TYPE timerMux0 = portMUX_INITIALIZER_UNLOCKED;
portMUX_TYPE timerMux1 = portMUX_INITIALIZER_UNLOCKED;

volatile uint8_t led1stat = 0; 
volatile uint8_t led2stat = 0; 

int steps0 = 200;
int steps1 = 200;

int count = 0;

boolean toggle = false;

void IRAM_ATTR onTimer0(){
  // Critical Code here
  portENTER_CRITICAL_ISR(&timerMux0);
  led1stat=1-led1stat;
  digitalWrite(14, led1stat);   // turn the LED on or off
  portEXIT_CRITICAL_ISR(&timerMux0);
}

void IRAM_ATTR onTimer1(){
  // Critical Code here
  portENTER_CRITICAL_ISR(&timerMux1);
  led2stat=1-led2stat;
  digitalWrite(27, led2stat);   // turn the LED on or off
  portEXIT_CRITICAL_ISR(&timerMux1);
}

void setup() {
  Serial.begin(115200);

  pinMode(27, OUTPUT);
  pinMode(14, OUTPUT);
  digitalWrite(27, LOW);    // turn the LED off by making the voltage LOW
  digitalWrite(14, LOW);    // turn the LED off by making the voltage LOW

  //delay(2000);

  Serial.println("start timer 1");
  timer1 = timerBegin(1, 80, true);  // timer 1, MWDT clock period = 12.5 ns * TIMGn_Tx_WDT_CLK_PRESCALE -> 12.5 ns * 80 -> 1000 ns = 1 us, countUp
  timerAttachInterrupt(timer1, &onTimer1, true); // edge (not level) triggered 
  timerAlarmWrite(timer1, 25000, true); // 250000 * 1 us = 250 ms, autoreload true

  Serial.println("start timer 0");
  timer0 = timerBegin(0, 80, true);  // timer 0, MWDT clock period = 12.5 ns * TIMGn_Tx_WDT_CLK_PRESCALE -> 12.5 ns * 80 -> 1000 ns = 1 us, countUp
  timerAttachInterrupt(timer0, &onTimer0, true); // edge (not level) triggered 
  timerAlarmWrite(timer0, 200000, true); // 2000000 * 1 us = 2 s, autoreload true

  // at least enable the timer alarms
  timerAlarmEnable(timer0); // enable
  timerAlarmEnable(timer1); // enable
}

void loop() {
  // nope nothing here
  //vTaskDelay(portMAX_DELAY); // wait as much as posible ...
  
  count++;
  
  Serial.println("hmm " + String(count));
  delay(1000);
 // Serial.println("erm" + String(count));
 // delay(1500);
  /*
    
  // test stopping timer1 
  if(count == 10){
    Serial.println("disable timer1 alarm");
    timerAlarmDisable(timer1);
    Serial.println("stop timer2");
    timerStop(timer1);
    timerDetachInterrupt(timer1);
    timerEnd(timer1);
    timer1 = NULL;
    digitalWrite(27, LOW);
  }
  // test stopping timer0 
  if(count == 20){
    Serial.println("disable timer0 alarm");
    timerAlarmDisable(timer0);
    Serial.println("stop timer0");
    timerStop(timer0);
    timerDetachInterrupt(timer0);
    timerEnd(timer0);
    timer0 = NULL;    
    digitalWrite(14, LOW);
  }
  */
  if(count == 30){
    
    Serial.println("wait a bit");
    
    //delay(5000);
    Serial.println("reset and change speeds");
    
    count = 0;    
    // toggle speeds every 30 counts
    int speed0 = (toggle == true)?200000:25000; 
    int speed1 = (toggle == true)?25000:200000; 

    toggle = !toggle;
    
    Serial.println("start timer 0 at " + String(speed0));
    timer0 = timerBegin(0, 80, true); 
    timerAttachInterrupt(timer0, &onTimer0, true); 
    timerAlarmWrite(timer0, speed0, true); 
    
    Serial.println("start timer 1 at " + String(speed1));
    timer1 = timerBegin(1, 80, true); 
    timerAttachInterrupt(timer1, &onTimer1, true);
    timerAlarmWrite(timer1, speed1, true);

    
    
    //timerStart(timer0);
    //timerStart(timer1);
    timerAlarmEnable(timer0);
    timerAlarmEnable(timer1);
    
    Serial.println("go at swapped speeds!!");

  }

  
  
  
}