Build Instructions

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  Run a Program

  bool isToneOn = false;
  int frequency = 3000;
  
  void setup() {
  //here is our PIR sensor
  pinMode(2, INPUT);
  //here is our buzzer
  pinMode(3, OUTPUT);
  
  }
  
  void loop() {
  //when PIR sensor gives us HIGH it means that it detects movement
  if(digitalRead(2) == HIGH){
  //we will turn on alarm for 15 seconds
  //we are using tone() so we can control frequency of our beep sound
  //to turn tone off we have to use noTone()
  //if you want to change frequency of tone you can do it in the variable
  //on the top of the code
  for(int a = 0; a < 30; a++){
  if(isToneOn){
  noTone(3);
  isToneOn = false;
  }else{
  //3 means our pin where buzzer is connected
  tone(3, frequency);
  //we have to change this variable to true, we have to know
  //when to turn buzzer on and when to turn it on
  isToneOn = true;
  }
  //delay 0.5 second, you can change this value so it will
  //beep slower or faster
  delay(500);
  }
  }
  }

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