// Define pins for the HC-SR04
const int trigPin = 9;
const int echoPin = 10;

// Define variables for duration and distance
long duration;
float distance;

void setup() {
  // Initialize the serial monitor
  Serial.begin(9600);
  
  // Set trigPin as OUTPUT and echoPin as INPUT
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
}

void loop() {
  // Clear the trigPin
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);

  // Trigger the sensor by setting trigPin HIGH for 10 microseconds
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);

  // Read the echoPin and calculate the duration
  duration = pulseIn(echoPin, HIGH);

  // Calculate the distance in cm
  distance = (duration * 0.034) / 2;

  // Print the distance on the serial monitor
  Serial.print("Distance: ");
  Serial.print(distance);
  Serial.println(" cm");

  // Delay before next reading
  delay(500);
}