This is the SparkFun Real Time Clock (RTC) Module, a small breakout that utilizes the DS1307 to track the current year, month, day, and time. The module comes fully assembled and includes a small CR1225 Lithium coin cell battery that will run the RTC for a minimum of 9 years (typical 17 years) without an external 5V power supply. The DS1307 RTC is accessed via the I2C protocol. We've written a test-bed to program the modules. This code should provide you with some insight into how to interface the module with any microcontroller using our example software's I2C and BCD routines. https://elecena.pl/product/4623595/sparkfun-real-time-clock-module 2014-05-09 https://elecena.pl/product/4623595/sparkfun-real-time-clock-module 2015-10-22 https://elecena.pl/product/4623595/sparkfun-real-time-clock-module 2016-04-01 https://elecena.pl/product/4623595/sparkfun-real-time-clock-module 2016-04-04 https://elecena.pl/product/4623595/sparkfun-real-time-clock-module 2016-11-25 https://elecena.pl/product/4623595/sparkfun-real-time-clock-module 2016-11-29 https://elecena.pl/product/4623595/sparkfun-real-time-clock-module 2016-12-09 https://elecena.pl/product/4623595/sparkfun-real-time-clock-module 2016-12-14 https://elecena.pl/product/4623595/sparkfun-real-time-clock-module 2017-03-31 https://elecena.pl/product/4623595/sparkfun-real-time-clock-module 2017-04-06 https://elecena.pl/product/4623595/sparkfun-real-time-clock-module 2017-11-24 https://elecena.pl/product/4623595/sparkfun-real-time-clock-module 2017-11-28 https://elecena.pl/product/4623595/sparkfun-real-time-clock-module 2018-05-05 https://elecena.pl/product/4623595/sparkfun-real-time-clock-module 2018-05-11 https://elecena.pl/product/4623595/sparkfun-real-time-clock-module 2018-05-15 https://elecena.pl/product/4623595/sparkfun-real-time-clock-module 2018-10-30 https://elecena.pl/product/4623595/sparkfun-real-time-clock-module 2018-11-21 https://elecena.pl/product/4623595/sparkfun-real-time-clock-module 2018-11-27 https://elecena.pl/product/4623595/sparkfun-real-time-clock-module 2019-03-15 https://elecena.pl/product/4623595/sparkfun-real-time-clock-module 2019-03-19 https://elecena.pl/product/4623595/sparkfun-real-time-clock-module 2019-07-04 https://elecena.pl/product/4623595/sparkfun-real-time-clock-module 2019-07-09 https://elecena.pl/product/4623595/sparkfun-real-time-clock-module 2019-11-29 https://elecena.pl/product/4623595/sparkfun-real-time-clock-module 2019-12-03 https://elecena.pl/product/4623595/sparkfun-real-time-clock-module 2022-02-21 https://elecena.pl/product/4623595/sparkfun-real-time-clock-module 2025-03-24 https://elecena.pl/product/4623595/sparkfun-real-time-clock-module 2025-06-26 https://elecena.pl/product/4623595/sparkfun-real-time-clock-module 2025-09-18 https://elecena.pl/product/4623595/sparkfun-real-time-clock-module 2025-09-21