const int ledPin=23;
const int frequency=500;
const int ledChannel=0;
const int resolution=8;
void setup() {
  // configure the pwm functionalites
  ledcSetup(ledChannel,frequency,resolution);
  //attach the channel to gpio to be controlled
  ledcAttachPin(ledPin,ledChannel);
}

void loop() {
  // to increase led brightness
  for(int dutyCycle=0;dutyCycle<=255;dutyCycle++) 
  {
    //changing the led brightness with pwm
    ledcWrite(ledChannel,dutyCycle);
    delay(15);
  }

}