RTC-DS3231 with 1602 LCD I2C - VTM Systems Store

/*
 * VTM Arduino Tutorial: DS3231 RTC + 1602 I2C LCD (Standard C++)
 * Tutorial: RTC-DS3231 with 1602 LCD I2C
 * 
 * Hardware Connections:
 *   DS3231 & 1602 LCD VCC -> Arduino 5V
 *   DS3231 & 1602 LCD GND -> Arduino GND
 *   DS3231 & 1602 LCD SDA -> Arduino Pin A4 (Uno) or SDA
 *   DS3231 & 1602 LCD SCL -> Arduino Pin A5 (Uno) or SCL
 * 
 * Libraries: RTClib by Adafruit, LiquidCrystal_I2C
 */

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

RTC_DS3231 rtc;
LiquidCrystal_I2C lcd(0x27, 16, 2); // Use 0x3F if your I2C module differs

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

  if (!rtc.begin()) {
    lcd.setCursor(0, 0);
    lcd.print("RTC Error!");
    while (1);
  }

  // Uncomment the line below once if you need to set the time, then re-upload:
  // rtc.adjust(DateTime(F(__DATE__), F(__TIME__)));

  lcd.clear();
}

void loop() {
  DateTime now = rtc.now();

  // Line 1: DATE YYYY-MM-DD
  char dateBuffer[17];
  snprintf(dateBuffer, sizeof(dateBuffer), "Date: %04d-%02d-%02d", 
           now.year(), now.month(), now.day());
  lcd.setCursor(0, 0);
  lcd.print(dateBuffer);

  // Line 2: TIME HH:MM:SS
  char timeBuffer[17];
  snprintf(timeBuffer, sizeof(timeBuffer), "Time: %02d:%02d:%02d", 
           now.hour(), now.minute(), now.second());
  lcd.setCursor(0, 1);
  lcd.print(timeBuffer);

  delay(1000);
}