// LED pin number
const int ledPin = 16;  // 16 corresponds to GPIO16

// setting PWM properties
const int frequency = 5000;  // setting frequency to 5KHz
const int ledChannel = 0;    // using led channel 0
const int resolution = 8;    // using 8 bit resolution to control the brightness from 0 to 255.
 
void setup(){
  // configure LED PWM functionalitites
  ledcSetup(ledChannel, frequency, resolution);
  
  // attach the channel to the GPIO to be controlled
  ledcAttachPin(ledPin, ledChannel);

  //code to loop the fucntionality 3 times and stop.
  int loop = 0;
  while(loop < 3){
    // increase the LED brightness 
  for(int i = 0; i <= 255; i++){   // where i is the dutyCycle of the PWM signal.
    // changing the LED brightness with PWM
    ledcWrite(ledChannel, i);
    delay(15);
  }

  // decrease the LED brightness
  for(int i = 255; i >= 0; i--){
    // changing the LED brightness with PWM
    ledcWrite(ledChannel, i);   
    delay(15);
  }
  loop++;
  }
}
 
void loop(){
  // To loop continuously place the code here.
}