int ledPinMerah = 8; // pinout 8 ke kaki LED positif LED Merah
int ledPinKuning = 9; // pinout 9 ke kaki LED positif LED Kuning
int ledPinHijau = 10; // pinout 10 ke kaki LED positif LED Hijau

void setup() {
  // put your setup code here, to run once:
  pinMode(ledPinMerah, OUTPUT);
  pinMode(ledPinKuning, OUTPUT);
  pinMode(ledPinHijau, OUTPUT);
}

void loop() {
  // put your main code here, to run repeatedly:
  digitalWrite(ledPinMerah, HIGH); // LED Merah hidup
  digitalWrite(ledPinKuning, LOW); // LED Kuning mati
  digitalWrite(ledPinHijau, LOW); // LED HIjau mati
  delay(2000); // Tunda 2000ms atau 2 detik

  digitalWrite(ledPinMerah, LOW); // LED Merah Mati
  digitalWrite(ledPinKuning, HIGH); // LED Kuning hidup
  digitalWrite(ledPinHijau, LOW); // LED HIjau mati
  delay(2000); // Tunda 2000ms atau 2 detik

  digitalWrite(ledPinMerah, LOW); // LED Merah mati
  digitalWrite(ledPinKuning, LOW); // LED Kuning mati
  digitalWrite(ledPinHijau, HIGH); // LED HIjau hidup
  delay(2000); // Tunda 2000ms atau 2 detik
}