int dataFromBT; int door1 = 2; int door2 = 3; void setup() { pinMode(door1, OUTPUT); pinMode(door2, OUTPUT); Serial.begin(9600); // start serial communication at 9600bps } void loop() { if( Serial.available() ) // if data is available to read { dataFromBT = Serial.read(); // read it and store it in 'val' } if( dataFromBT == '1' ) // if '1' was received { digitalWrite(door1, HIGH); // activate transistor/relay delay(2000); digitalWrite(door1, LOW); dataFromBT='0'; } else if (dataFromBT == '2' ) { digitalWrite(door2, HIGH); // activate transistor/relay delay(2000); digitalWrite(door2, LOW); dataFromBT='0'; } delay(100); }