void setup() {
  // put your setup code here, to run once:
Serial.begin(115200);
if(!Serial) Serial.println("serial tidak berfungsi");
pinMode(12, OUTPUT); // led merah
}

void loop() {
  // put your main code here, to run repeatedly:
  // lampu led merah o/off
digitalWrite(12, HIGH);
Serial.println("Lampu merah nyala");
delay(6000);
digitalWrite(12, LOW);
Serial.println("Lampu merah mati");

  // lampu led kuning o/off
digitalWrite(11, HIGH);
Serial.println("Lampu kuning nyala");
delay(3000);
digitalWrite(11, LOW);
Serial.println("Lampu kuning mati");

  // lampu led hijau o/off
digitalWrite(10, HIGH);
Serial.println("Lampu hijau nyala");
delay(5000);
digitalWrite(10, LOW);
Serial.println("Lampu hijau mati");
}