int sensor = 2; 
int val;             // the pin that the sensor is atteched to
void setup() {
  pinMode(sensor, INPUT);    // initialize sensor as an input
  Serial.begin(9600);        // initialize serial
}

void loop(){
  val = digitalRead(sensor);   // read sensor value
  if(val>0){
  Serial.println("Motion detected!");
  } 
  else{
  Serial.println("Motion not detected!");
}
  delay(1000);
  }