//A SOFIYUL FUADIKA 01 XI TEI 1

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

// Inisialisasi LCD I2C
LiquidCrystal_I2C lcd(0x27, 16, 2); 
// Jika tidak tampil, coba ganti 0x27 jadi 0x3F

// Ultrasonic
const int trigPin = 3;
const int echoPin = 2;

// LED
const int ledMerah = 4;
const int ledHijau = 5;

long waktu;
int jarak;

void setup() {
pinMode(trigPin, OUTPUT);
pinMode(echoPin, INPUT);

pinMode(ledMerah, OUTPUT);
pinMode(ledHijau, OUTPUT);

lcd.init();
lcd.backlight();

lcd.setCursor(0,0);
lcd.print("Sensor Jarak");

Serial.begin(9600);
}

void loop() {

// Trigger Ultrasonic
digitalWrite(trigPin, LOW);
delayMicroseconds(2);

digitalWrite(trigPin, HIGH);
delayMicroseconds(10);
digitalWrite(trigPin, LOW);

// Baca Echo
waktu = pulseIn(echoPin, HIGH);
jarak = waktu * 0.034 / 2;

// Tampilkan ke LCD
lcd.setCursor(0,1);
lcd.print("Jarak: ");
lcd.print(jarak);
lcd.print(" cm   ");

// Logika LED
if (jarak < 15) {
digitalWrite(ledMerah, HIGH);
digitalWrite(ledHijau, LOW);
} else {
digitalWrite(ledMerah, LOW);
digitalWrite(ledHijau, HIGH);
}
delay(500);
}