char inChar; // define a variable to store characters received from serial port

void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);
}

void loop() {
  // put your main code here, to run repeatedly:
  if(Serial.available()){ // judge whether data has been received --> Scanning for user input
    inChar = Serial.read(); // read the data
    Serial.print("received:");
    Serial.println(inChar);
  }
}