#define TRIGGER_PIN_1 2
#define ECHO_PIN_1 3
#define BUZZER_PIN_1 7

/* #define TRIGGER_PIN_2 5
#define ECHO_PIN_2 4
#define BUZZER_PIN_2 6 */

void setup() {
  Serial.begin(9600);
  
  pinMode(TRIGGER_PIN_1, OUTPUT);
  pinMode(ECHO_PIN_1, INPUT);
  pinMode(BUZZER_PIN_1, OUTPUT);

  /* pinMode(TRIGGER_PIN_2, OUTPUT);
  pinMode(ECHO_PIN_2, INPUT);
  pinMode(BUZZER_PIN_2, OUTPUT); */
}

void measureDistance(int triggerPin, int echoPin, int buzzerPin) {
  long duration, distance;

  // Send a pulse to the ultrasonic sensor to start measurement
  digitalWrite(triggerPin, LOW);
  delayMicroseconds(2);
  digitalWrite(triggerPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(triggerPin, LOW);

  // Measure the time it takes for the pulse to return
  duration = pulseIn(echoPin, HIGH);

  // Calculate the distance in centimeters
  distance = (duration * 0.0343) / 2;

  Serial.print("Distance: ");
  Serial.print(distance);
  Serial.println(" cm");

  // Check if an object is within a certain range (adjust as needed)
  if (distance < 30) {
    // If an object is detected, activate the buzzer
    tone(buzzerPin, 1000); // You can adjust the frequency as needed
  } else {
    // If no object is detected or it's out of range, turn off the buzzer
    noTone(buzzerPin);
  }
}

void loop() {
  measureDistance(TRIGGER_PIN_1, ECHO_PIN_1, BUZZER_PIN_1);
  delay(100); // Add a small delay between sensor readings

  /* measureDistance(TRIGGER_PIN_2, ECHO_PIN_2, BUZZER_PIN_2);
  delay(1000); // Adjust the delay as needed for your application */
}