light.ino

char data = 0;
void setup() {
  // put your setup code here, to run once:
  pinMode(12,OUTPUT);
  Serial.begin(9600);
}

void loop() {
  // put your main code here, to run repeatedly:
  if(Serial.available() > 0){
    data = Serial.read();
    if(data=='1'){
      digitalWrite(12,HIGH);
    }else if(data=='2'){
      digitalWrite(12,LOW);
    }
  }
}