#define ECHO_PIN 2
#define TRIG_PIN 3

// Menentukan PIN untuk LED
uint8_t ledPin[] = {13, 12, 11, 10, 9}; // pin led
uint8_t nyalaLED = 0; // jml led menyala

void setup() {
  Serial.begin(115200);
  pinMode(TRIG_PIN, OUTPUT);
  pinMode(ECHO_PIN, INPUT);

  for (uint8_t j = 0; j < 5; j++) {
    pinMode(ledPin[j], OUTPUT);
  }
}

float bacaJarakCM() {
  digitalWrite(TRIG_PIN, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIG_PIN, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN, LOW);
  int durasi = pulseIn(ECHO_PIN, HIGH);
  return durasi * 0.03435 / 2; // Kec. suara 343.5 m/s atau 0.03435 cm/ms
}

void loop() {
  float jarak = bacaJarakCM();

  if (jarak > 380) {
    nyalaLED = 0;
  } else if (jarak < 380 && jarak > 300) {
    nyalaLED = 1;
  } else if (jarak < 300 && jarak > 200) {
    nyalaLED = 2;
  } else if (jarak < 200 && jarak > 100) {
    nyalaLED = 3;
  } else if (jarak < 100 && jarak > 20) {
    nyalaLED = 4;
  } else {
    nyalaLED = 5;
  }

  // MEMBERIKAN INSTRUKSI KE AKTUATOR (LED)
  for (uint8_t i = 0; i < nyalaLED; i++) {
    digitalWrite(ledPin[i], HIGH);
  }
  for (uint8_t i = nyalaLED; i < 5; i++) {
    digitalWrite(ledPin[i], LOW);
  }

  Serial.print("Jarak (cm): ");
  Serial.println(bacaJarakCM());

  delay(100);
}