#define LED1 4 //mendefinisikan pin 4 sebagai LED1
#define LED2 5
#define LED3 6
#define LED4 7
 
void setup() {
//setting LED1-LED4 sebagai output
pinMode (LED1, OUTPUT);
pinMode (LED2, OUTPUT);
pinMode (LED3, OUTPUT);
pinMode (LED4, OUTPUT);
Serial.begin(9600);
}
 
void loop() {
switch (4) { //case 4 yang akan dieksekusi
case 1:
  digitalWrite (LED1, HIGH);
  digitalWrite (LED2, HIGH);
  digitalWrite (LED3, LOW);
  digitalWrite (LED4, LOW);
break;
case 2:
  digitalWrite (LED1, HIGH);
  digitalWrite (LED2, LOW);
  digitalWrite (LED3, HIGH);
  digitalWrite (LED4, LOW);
break;
case 3:
  digitalWrite (LED1, HIGH);
  digitalWrite (LED2, LOW);
  digitalWrite (LED3, LOW);
  digitalWrite (LED4, HIGH);
  delay(1000);
break;
case 4:
  digitalWrite (LED1, HIGH);
  digitalWrite (LED2, HIGH);
  digitalWrite (LED3, HIGH);
  digitalWrite (LED4, HIGH);
  delay(1000);
break;
default:
  Serial.println ("Terjadi kesalahan");
break;
}
}