#define ECHO_PIN 5
#define TRIG_PIN 4
#define LedMerah 8
#define LedKuning 7
#define LedHijau 6

void setup() {
  Serial.begin(115200);
  pinMode(LED_BUILTIN, OUTPUT);
  pinMode(TRIG_PIN, OUTPUT);
  pinMode(ECHO_PIN, INPUT);
  pinMode(LedHijau, OUTPUT);
  pinMode(LedMerah, OUTPUT);
  pinMode(LedKuning, OUTPUT);
}

float readDistanceCM() {
  digitalWrite(TRIG_PIN, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIG_PIN, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN, LOW);
  int duration = pulseIn(ECHO_PIN, HIGH);
  return duration * 0.034 / 2;
}

void loop() {
  digitalWrite(TRIG_PIN, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIG_PIN, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN, LOW);
  int duration = pulseIn(ECHO_PIN, HIGH);
  float distance = duration * 0.034 / 2;

  Serial.print("Jarak: ");
  Serial.println(distance);
  if (distance >= 100){
  digitalWrite(LedMerah, HIGH);
  digitalWrite(LedKuning, LOW);
  digitalWrite(LedHijau, LOW);
  

  }if (distance > 50 && distance <= 100) {
    digitalWrite(LedKuning, HIGH);
    digitalWrite(LedMerah, LOW);
    digitalWrite(LedHijau, LOW);

  }if (distance <= 50) {
    digitalWrite(LedHijau, HIGH);
    digitalWrite(LedKuning, LOW);
    digitalWrite(LedMerah, LOW);
  }

  delay(100);
}