ArduinoBasics - 7. Buzzer, button, LED alarm

int led = 9;
int buzzer = 10;
int button = 11;
bool isPressed;

void setup() {
  pinMode(led, OUTPUT);
  pinMode(buzzer, OUTPUT);
  pinMode(button, INPUT);
}

void loop() {
  isPressed = digitalRead(button);
  if(isPressed == true){
    digitalWrite(led, HIGH);
    tone(buzzer, 400);
    delay(200);
    digitalWrite(led, LOW);
    noTone(buzzer);
    delay(200);
  }
  else{
    digitalWrite(led, LOW);
  }
}