#include <Arduino.h>
#include <Wire.h>
#include <LiquidCrystal_I2C.h>

// Inisialisasi LCD12C
LiquidCrystal_I2C lcd(0x27, 16, 2);

// Pin untuk LED
const int redPin = 9;
const int yellowPin = 10;
const int greenPin = 11;


void setup() {
  // Inisialisasi serial monitor
  Serial.begin(9600);
  
  // Inisialisasi LCD12C
  lcd.init();
  lcd.backlight();
  
  // Inisialisasi pin LED
  pinMode(redPin, OUTPUT);
  pinMode(yellowPin, OUTPUT);
  pinMode(greenPin, OUTPUT);
  

void loop() {
  // Baca jarak dari sensor ultrasonik
  long duration, distance;
  pinMode(9, OUTPUT);
  digitalWrite(9, LOW);
  delayMicroseconds(10);
  digitalWrite(9, HIGH);
  delayMicroseconds(10);
  digitalWrite(9, LOW);
  duration = pulseIn(10, HIGH);
  distance = (duration / 2) / 29.1; // Konversi waktu ke jarak dalam cm
 

  // Tampilkan jarak pada LCD12C
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Jarak: ");
  lcd.print(distance);
  lcd.print(" cm");
  
  // Kontrol LED berdasarkan jarak
  if (distance > 30) {
    digitalWrite(greenPin, HIGH);
    digitalWrite(redPin, LOW);
    digitalWrite(yellowPin, LOW);
  } else if (distance >= 15 && distance <= 29) {
    digitalWrite(greenPin, LOW);
    digitalWrite(redPin, LOW);
    digitalWrite(yellowPin, HIGH);
  } else if (distance >= 0 && distance < 15) {
    digitalWrite(greenPin, LOW);
    digitalWrite(redPin, HIGH);
    digitalWrite(yellowPin, LOW);
  } else {
    digitalWrite(greenPin, LOW);
    digitalWrite(redPin, LOW);
    digitalWrite(yellowPin, LOW);
  }

  

  // Tunggu selama 1 detik sebelum mengukur lagi
  delay(1000);
}