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

RTC_DS3231 rtc;
LiquidCrystal_I2C lcd(0x27, 16, 2);

void setup() {
  Serial.begin(115200);
  Wire.begin();
  lcd.init();
  lcd.backlight();

  if (! rtc.begin()) {
    Serial.println("Couldn't find RTC");
    while (1);
  }

  if (! rtc.begin()) {
    Serial.println("RTC is NOT running!");
    rtc.adjust(DateTime(F(__DATE__), F(__TIME__)));
  }
}

void loop() {
  DateTime now = rtc.now();
  lcd.setCursor(0,0);
  lcd.print(now.hour());
  lcd.print(":");
  lcd.print(now.minute());
  lcd.print(":");
  lcd.print(now.second());
  lcd.setCursor(0,1);
  lcd.print(now.day());
  lcd.print("/");
  lcd.print(now.month());
  lcd.print("/");
  lcd.print(now.year());

  if (now.minute() == 0) {
    tone(8, 1000, 500);
    delay(1000);
  } else if (now.minute() == 30) {
    tone(8, 1000, 500);
    delay(1000);
  }

  delay(1000);
}