int led =13;
int pirdata =15 ;
int pirstate =LOW ;
int value =0;


void setup() {
  pinMode(led, OUTPUT);
  pinMode(pirdata, INPUT);
  Serial.begin(9600);
}

void loop() {
  value = digitalRead(pirdata);
 if (value == HIGH) {
  digitalWrite(led, HIGH);
  if (pirstate == LOW)
  {
    Serial.println("motion detected!");
     pirstate = HIGH ;

  }
  else {
    digitalWrite(led, LOW);
    if(pirstate == HIGH){

      Serial.println(" motion ended!");

      pirstate == LOW;
     }
  }
 }
}