The RTC module tracks time with separate registers for hours, minutes, and seconds. The calendar registers track date, day of the week, month and year with automatic leap year correction.
The RTC is capable of running from an alternate source of power, so it can continue to keep time while the primary source of power is off or unavailable. The timer remains operational when the core domain is in power-down. The kernel part of the RTC keeps
running as long as the hibernate domain is powered with an alternate supply source. The alternate source can be for example a lithium battery or a super capacitor.
