int pir=12;
int buzzpin=11;

void setup() {
  // put your setup code here, to run once:
  pinMode(pir, INPUT);
  pinMode(buzzpin, OUTPUT);
}

void loop() {
  // put your main code here, to run repeatedly:
  int value_of_pir =  digitalRead(pir);
  if (value_of_pir== HIGH)
  {
  tone(buzzpin,500,3);
  }
  else
  {
  tone(buzzpin,0,1);
  }
}