//Program Water Leve;
// By Naufal azhar XI TEDK 1

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

int led = A0;
int buzzer = 2;
int trig = 6;
int echo = 5;
long waktu,jarak;

void setup() {
  lcd.init();
  lcd.backlight();
  lcd.clear();
  lcd.setCursor(0,0);
  lcd.print("   Welcome To   ");
  lcd.setCursor(0,1);
  lcd.print("   Water Level   ");
  delay(2000);
  lcd.clear();

  pinMode(trig, OUTPUT);
  pinMode(echo, INPUT);
  Serial. begin(9600);

  pinMode(led,OUTPUT);
  pinMode(buzzer, OUTPUT);
}

void loop() {
  digitalWrite(trig, HIGH);
  delayMicroseconds(5);
  digitalWrite(trig, LOW);
  delayMicroseconds(5);

  waktu = pulseIn(echo, HIGH);
  jarak = waktu/58,4;

  Serial.print("Jarak = ");
  Serial.print(jarak);
  Serial.println(" cm");

  lcd.setCursor(0,0);
  lcd.print("Jarak = ");
  lcd.setCursor(8,0);
  lcd.print(jarak);
  lcd.print(" cm");
  delay(200);

  if(jarak>100){
    tone(buzzer, 200);
    digitalWrite(led, HIGH);
  }

  if(jarak<100){
    noTone(buzzer);
  }

  if(jarak<20){
    digitalWrite(led, LOW);
  }
}