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

const int trigPin = 6;
const int echoPin = 5;
int buzzer = 8;

long duration;
int JarakCm, JarakInch;

void setup() {
  lcd.begin(12,2);

  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
  Serial.begin(9600);
}

void loop() {
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);

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

  duration = pulseIn(echoPin, HIGH);
  JarakCm = duration*0.03/2;
  JarakInch = duration*0.0133/2;

  lcd.setCursor(0,0);
  lcd.print("Jarak :");
  lcd.print(JarakCm);
  lcd.print(" Cm ");
  delay(10);
  lcd.setCursor(0,1);
  lcd.print("Jarak :");
  lcd.print(JarakInch);
  lcd.print(" Inch ");
  delay(10);

  if (JarakCm<=20){
    tone(buzzer,1030);
    delay(400);
    noTone(12);
    delay(100);
  }

  }