#define LedMerah 2 
#define LedKuning 4 
void setup() {
  // put your setup code here, to run once:
pinMode(LedMerah, OUTPUT );
pinMode(LedKuning, OUTPUT ) ;
}

void loop() {
  // put your main code here, to run repeatedly:
digitalWrite(LedMerah, HIGH ) ;
digitalWrite(LedKuning, LOW ) ;
delay(500) ;
digitalWrite(LedMerah, LOW ) ;
digitalWrite(LedKuning, HIGH ) ;
delay(300) ;
}