void setup() {
  Serial.begin(9600);
  pinMode(13, OUTPUT);
}
void loop() {
}
void serialEvent() {
  while (Serial.available()) {
    int data = Serial.parseInt();
    if (Serial.read() == char(13)) {
      if (data == 1) digitalWrite(13, HIGH);
      else digitalWrite(13, LOW);
    }
  }
}