The RTC interfaces to logic in the PMC and includes these features:
- An APB interface to access the registers within the controller and the RTC counters
- Interrupt status, interrupt mask, interrupt enable, and interrupt disable registers manage the seconds and alarm interrupts
- The RTC control register enables the crystal oscillator, controls power to the RTC, and enables address errors when accesses are made to the regions within the RTC address space that are not mapped to registers
Important: The RTC control register must be
programmed every time the PMC is powered down. Otherwise, the value returned by
reading the control register can be different from the actual control settings
stored in the battery power domain.