/*
  PIR sensor tester
*/
int LED_PIN = 12;             // choose the pin for the LED
int PIR_PIN = 2;              // choose the input pin (for PIR sensor)
int pirState = LOW;           // we start, assuming no motion detected
int pirVal = 0;               // variable for reading the pin status

void setup() {
  pinMode(LED_PIN, OUTPUT);   // declare LED as output
  pinMode(PIR_PIN, INPUT);    // declare sensor as input

  Serial.begin(9600);
}

void loop() {
  pirVal = digitalRead(PIR_PIN);  // read input value
  if (pirVal == HIGH) {           // check if the input is HIGH
    digitalWrite(LED_PIN, HIGH);  // turn LED ON
    if (pirState == LOW) {
      // we have just turned on
      Serial.println("Motion detected!");
      // We only want to print on the output change, not state
      pirState = HIGH;
    }
  } else {
    digitalWrite(LED_PIN, LOW); // turn LED OFF
    if (pirState == HIGH) {
      // we have just turned of
      Serial.println("Motion ended!");
      // We only want to print on the output change, not state
      pirState = LOW;
    }
  }
}