#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x27, 16, 2);

const int trigger = 10;
const int echo = 9;
const int LED = 11;

void setup() {
  lcd.init();
  lcd.backlight();
  pinMode (trigger, OUTPUT);
  pinMode (echo, INPUT);
  pinMode (LED, OUTPUT);
}
void loop(){
  digitalWrite(trigger, LOW);
  delayMicroseconds(5);
  
  digitalWrite(trigger, HIGH);
  delayMicroseconds(13);
  digitalWrite(trigger, LOW);
  
  long duration = pulseIn(echo, HIGH);
  
  long distance = (duration * 0.0343) / 2;
  
  Serial.print("Sensor Distance: ");
  Serial.println(distance);

  if(distance > 30){
    lcd.clear();
    digitalWrite(LED, HIGH);
    lcd.setCursor(0,0);
    lcd.print("LED ON");
    delay(500);
  }
  if(distance < 30){
    lcd.clear();
    digitalWrite(LED, LOW);
    lcd.setCursor(0,0);
    lcd.print("LED OFF");
    delay(500);
}
}