#define TRIG_PIN 14
#define ECHO_PIN 27
#define LED_PIN 2





void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);
  
  pinMode(TRIG_PIN, OUTPUT);
  pinMode(ECHO_PIN, INPUT);
  pinMode(LED_PIN, OUTPUT);
}

void loop() {
  long duration;
  float distance;

  digitalWrite( TRIG_PIN, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIG_PIN, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN, LOW);

  duration = pulseIn(ECHO_PIN, HIGH, 30000);

  distance = duration * 0.0343 / 2;


if (duration == 0){
  Serial.println("tidak ada pantulan");
  digitalWrite(LED_PIN, LOW);
} else{
  Serial.print("jarak: ");
  Serial.print(distance);
  Serial.println(" cm");
  
  if (distance < 30) {
    digitalWrite(LED_PIN, HIGH);
    Serial.println("LED MENYALA");
  } else{
    digitalWrite(LED_PIN, LOW);
    Serial.println("LED MATI");
  }
}
  
  delay(500);
}