const int ledPin = 8;    //define the LED pin
  
  void setup(){
  
    pinMode(ledPin, OUTPUT);    //initialize LED output
    Serial.begin(9600);         //start the serial communication
  }
  
  void loop(){
  
    if(Serial.available() > 0){           //if some data is available of in the serial port
      char ledPinState = Serial.read();   //read the value
      if(ledPinState == '1'){             //if statement will be true(1)
        digitalWrite(ledPin, HIGH);       //turn ON the LED
      }
      if(ledPinState == '0'){             //if statement will be false(0)
        digitalWrite(ledPin, LOW);        //turn OFF the LED
      }
    }
  }