#define trigPin 13
#define echoPin 12
#define speaker 11
#define led2 10

void setup() {
  Serial.begin(9600);
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
  pinMode(speaker, OUTPUT);
  pinMode(led2, OUTPUT);
}

void loop() {
  long duration, distance;
  digitalWrite(trigPin, LOW);  
  delayMicroseconds(2);   
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10); 
  digitalWrite(trigPin, LOW);
  
  duration = pulseIn(echoPin, HIGH);
  distance = (duration / 2) / 29.1;
  
  Serial.print("Distance: ");
  Serial.println(distance);
  
  if (distance < 200) {  // Set your distance threshold
    digitalWrite(led2, HIGH);
    tone(speaker, 1000); // Set a frequency (e.g., 1000 Hz)
    delay(300);          // Play sound and turn on LED for 300 milliseconds
    digitalWrite(led2, LOW);
    noTone(speaker);
    delay(300);          // Turn off LED and sound for 300 milliseconds
  } else {
    digitalWrite(led2, LOW);
    noTone(speaker);
  }
}