Digital Clock with ESP32 and DS1307 RTC (I2C + LCD)

In this project, we display the time and date on a 16x2 I2C LCD screen using the DS3231 real-time clock (RTC) module. The DS3231 is a highly accurate RTC that deviates by only a few seconds per year thanks to its internally temperature-compensated crystal; it maintains the time even if the ESP32 is powered off, thanks to its battery backup. Both modules share the same I2C bus (SDA/SCL), allowing us to learn how to control multiple devices using just two signal wires.