#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x27, 20, 4);
#define led 13
#define ECHO_PIN 4
#define TRIG_PIN 2

void setup() {
  pinMode(13, OUTPUT);
  pinMode(TRIG_PIN, OUTPUT);
  pinMode(ECHO_PIN, INPUT);
  lcd.init();
  lcd.backlight();
  // put your setup code here, to run once:
  Serial.begin(115200);
  Serial.println("Hello, ESP32!");
}

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;

  lcd.setCursor(2,0);
  lcd.print("Jarak: ");
  lcd.println(distance);

  if(200>distance){
    lcd.setCursor(2,1);
    lcd.print("Hati-hati");
    digitalWrite(13, HIGH);
    delay(distance);
    digitalWrite(13, LOW);
    delay(distance);
  }else{
    lcd.setCursor(2,1);
    lcd.print("Aman     ");
  }

  delay(100);
}