const int PIN_12 = 12; 

void setup() {
  Serial.begin(9600);  
    pinMode(PIN_12, OUTPUT); 
    }

    void loop() {
      while (Serial.available() != 0) { 
          int bilangan = Serial.parseInt(); 
              Serial.flush(); 

                  if (bilangan == 1) {
                        digitalWrite(PIN_12, HIGH); 
                              Serial.println("LED dihidupkan Bro");
                                  } else if (bilangan == 0) {
                                        digitalWrite(PIN_12, LOW); 
                                              Serial.println("LED dimatikan Bro");
                                                  }

                                                      delay(20);
                                                        }
                                                        }