## RTC Introduction


## Coin Cell Battery

The Location of coin-type battery is shown by this figure:
![CBattery](/helios64/img/rtc/cbat.jpg)

The battery type is CR1225, this device has diameter of 12.5mm and 2.5mm thickness.
In above figure the positive (+) polarity is heading downward to the CPU heatsink side.
This battery is used only for keep the RTC (Real Time Clock) running.