ESP32 Forum

Posted: **Wed Mar 10, 2021 2:00 pm**

Hey there!
I'm having some troubles using more than one timer with my ESP32. The second interrupt works well, but I seem to be accessing the first one only one time. It must be some variable I'm forgetting to update, but I just can't get it to work.

It seems as if interruptCounter isn't increasing again, but I don't know why it wouldn't.

I attach the relevant parts of the code:

Declarations/Initializations:

Code: Select all

volatile int interruptCounter; 
int totalInterruptCounter;
hw_timer_t * timer = NULL;
portMUX_TYPE timerMux = portMUX_INITIALIZER_UNLOCKED;

volatile int interruptCounter2; 
int totalInterruptCounter2;
hw_timer_t * timer2 = NULL;
portMUX_TYPE timerMux2 = portMUX_INITIALIZER_UNLOCKED;

volatile int interruptCounter;
int totalInterruptCounter;
hw_timer_t * timer = NULL;
portMUX_TYPE timerMux = portMUX_INITIALIZER_UNLOCKED;

void IRAM_ATTR onTime(){ 
  portENTER_CRITICAL_ISR(&timerMux);
  interruptCounter++;
  portEXIT_CRITICAL_ISR(&timerMux);
  }
  
volatile int interruptCounter2; 
int totalInterruptCounter2;
hw_timer_t * timer2 = NULL;
portMUX_TYPE timerMux2 = portMUX_INITIALIZER_UNLOCKED;

void IRAM_ATTR onTime2(){ 
  portENTER_CRITICAL_ISR(&timerMux2);
  interruptCounter2++;
  portEXIT_CRITICAL_ISR(&timerMux2);  
}

Setup:

Code: Select all

  pinMode(pinSend, OUTPUT); 

timer = timerBegin(0,80,true); //1MHz, prescaler de 80
timerAttachInterrupt(timer, &onTime, true);
timerAlarmWrite(timer, 10, true); //interrumps every 10 micros
timerAlarmEnable(timer);

timer2 = timerBegin(1,80,true); //1MHz, prescaler de 80
timerAttachInterrupt(timer2, &onTime2, true);
timerAlarmWrite(timer2, 501, true); //interrumpe every 501 micros
timerAlarmEnable(timer2);

Loop:

Code: Select all

      if (interruptCounter2 > 0) { //this one works ok!!
        if (flag_pulse == 1){ 
          portENTER_CRITICAL(&timerMux2);
          interruptCounter2--;
          portEXIT_CRITICAL(&timerMux2);
         totalInterruptCounter2++;
          if (totalInterruptCounter2 < lastDuty) {
            digitalWrite(pinSend, HIGH);
          }
          else {
            digitalWrite(pinSend, LOW);
          if (totalInterruptCounter2 = 20)
          totalInterruptCounter2 = 0;
      }}
      }
        
      if (interruptCounter > 0) { //this only works one time!
        if (flag_data){
               portENTER_CRITICAL(&timerMux);
               interruptCounter--;
               portEXIT_CRITICAL(&timerMux);
               totalInterruptCounter++;
               flag_samples++;
               data[flag_samples] = analogRead(34);
               Serial.println(totalInterruptCounter); //for debug purpose only, it only prints once...
               if (totalInterruptCounter = 500){
                flag_send = 1; 
                flag_data = 0; 
                flag_pulse = 0; 
                totalInterruptCounter = 0;
                flag_samples = 0;
           }
        }

//Send data via BLE
        if (flag_send) { //this works ok! although it's sending empty data because it doesn't read the pin
          for (int k = 0; k< samples; k++) {
          Serial.println((3.3*(data[k]).toInt()/4096));
          voltage[k] = String(100-((3.3*(data[k]).toInt()/4096))*20);
          pCharacteristic->setValue(voltage[k].c_str()); 
          pCharacteristic->notify();
          delay(3);
        }
        flag_send = 0;
        }
     }

PS. For a brief explanation of the code, with timer2 I generate pulse trains with different frequencies. With timer I analogread the response. I could read the response just fine, until I added the other interrupt.

If anyone can guide me in the right direction, that would be really helpful!
Thanks in advance

Posted: **Wed Mar 10, 2021 4:17 pm**

Nevermind, I just fixed it.

Now the interrupt looks like this:

Code: Select all

      if (interruptCounter > 0) {
        if (flag_data){
               portENTER_CRITICAL(&timerMux);
               interruptCounter--;
               portEXIT_CRITICAL(&timerMux);
               totalInterruptCounter++;
               
               if (flag_samples<500){
               dato[flag_samples] = analogRead(34);
               flag_samples++;
               }
               else {
                flag_send = 1;
                flag_data = 0; 
                flag_pulse = 0;
                flag_samples = 0;
           }
        }

Posted: **Wed Mar 10, 2021 4:29 pm**

Hi,

Good to know!

Changing the title to SOLVED.

ESP32 Forum

[SOLVED] ESP32 - Using more than one timer

[SOLVED] ESP32 - Using more than one timer

Re: ESP32 - Using more than one timer

Re: [SOLVED] ESP32 - Using more than one timer