The RTC will continue to operate in any sleep mode where the selected source clock is running. The RTC interrupts can be used to wake up the device from sleep modes. Events connected to the event system can trigger other operations in the system without exiting sleep modes. Refer to the Power Manager for details on the different sleep modes.
The RTC will be reset only at power-on (POR) or by setting the Software Reset bit in the Control A register (CTRLA.SWRST=1).