// the number of the LED pin
const int ledPin1 = 16;  // 16 corresponds to GPIO16
const int ledPin2 = 5;
const int ledPin3 = 18;
// setting PWM properties
const int freq = 1000;
const int ledChannel = 0;
const int resolution = 8;
 
void setup(){
  // configure LED PWM functionalitites
  ledcSetup(ledChannel, freq, resolution);
  
  // attach the channel to the GPIO to be controlled
  ledcAttachPin(ledPin1, ledChannel);
  ledcAttachPin(ledPin2, ledChannel);
  ledcAttachPin(ledPin3, ledChannel);
}
 
void loop(){
  // merah, kuning, hijau
  for(int dutyCycle = 0; dutyCycle <= 255; dutyCycle++){   
    // changing the LED brightness with PWM
    ledcWrite(ledChannel, dutyCycle);
    delay(10);
  }

  // merah, kuning, hijau
  for(int dutyCycle = 255; dutyCycle >= 0; dutyCycle--){
    // changing the LED brightness with PWM
    ledcWrite(ledChannel, dutyCycle);   
    delay(10);
  }
}