The Real Time Clock (RTC) module can be used to retain the time, even when the Arduino is powered off. These modules use I2C communication.
Learn how to use the Real Time Clock (RTC) module with the Arduino:
Best Tools and Gear for Makers
The Real Time Clock (RTC) module can be used to retain the time, even when the Arduino is powered off. These modules use I2C communication.
Learn how to use the Real Time Clock (RTC) module with the Arduino: