Checkout Raspberry Pi Real Time Clock (RTC) Expansion Module! Utilises Maxim DS1307 chip and CR1220 button cell on the board to keep the real time for a long time after the Raspberry Pi has it’s power down. It communicates with Raspberry Pi through I2C bus.
Real-Time Clock Counts Seconds, Minutes,Hours, Day, Date, Month, and Year with Leap Year Compensation Valid Up to 2100. Set a serial port (TTL) for debugging.
Not only that, it provides programmable square-wave output signal and Automatic Power-Fail Detect and Switch Circuitry.
Raspberry Pi B module 2X13 connection port
Raspberry Pi A+/B+/2 module 2X13 connection port
2*5pin 2.54mm connector
Learn more or Buy Raspberry Pi RTC Expansion Module from Pakronics: