int inInt; // store data received from serial port
int ledPin = 11; // we will be using pin 11 for LED

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

void loop() {
  // put your main code here, to run repeatedly:
  if(Serial.available()){ // scans and judges input
    inInt = Serial.parseInt(); // reads an integer
    Serial.print("received:"); // "received:"
    Serial.println(inInt); // print out the received data
    // use received integer and convert it to PWM duty cycle of ledPin port
    analogWrite(ledPin, constrain(inInt, 0, 255));
  }
}