#define triggerPin 15 // Pin connected to the TRIGGER pin of the ultrasonic sensor
#define echoPin 4    // Pin connected to the ECHO pin of the ultrasonic sensor
#define buzzerPin 5 // Pin connected to the buzzer

void setup() {
  pinMode(triggerPin, OUTPUT);// Initialize the TRIGGER pin as an output
  pinMode(echoPin, INPUT);   // Initialize the ECHO pin as an input
  pinMode(buzzerPin, OUTPUT);// Initialize the buzzer pin as an output
}

void generateTriggerPulse() {
  digitalWrite(triggerPin, LOW);
  delayMicroseconds(2);
  digitalWrite(triggerPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(triggerPin, LOW);
}

long getEchoDuration() {
  return pulseIn(echoPin, HIGH);
}

int convertToDistance(long duration) {
  return duration * 0.0343 / 2;
}

void activateBuzzer() {
  tone(buzzerPin, 1000, 1000); // Generate a 1000ms beep
  delay(1000);                 // Wait for 1000ms
  noTone(buzzerPin);          // Turn off the buzzer
  delay(100);                 // Wait for 100ms
}

void loop() {
  generateTriggerPulse();
  long duration = getEchoDuration();
  int distance = convertToDistance(duration);
  
  if (distance < 50) {
    activateBuzzer();
  }
  
  delay(100);
}