21.6.5 Events
The RTC can generate the following output events:
- Overflow (OVF): Generated when the counter has reached its top value and wrapped to zero.
- Tamper (TAMPER): Generated on detection of valid signal on a tamper input pin or tamper event input.
- Compare (CMPn): Indicates a match between the counter value and the compare register.
- Alarm (ALARM): Indicates a match between the clock value and the alarm register.
- Period n (PERn): The corresponding bit in the prescaler has toggled. Refer to Periodic Intervals for details.
- Periodic Daily (PERD): Generated when the COUNT/CLOCK has incremented at a fixed period of time.
Setting the Event Output bit in the Event Control Register (EVCTRL.xxxEO=1) enables the corresponding output event. Writing a zero to this bit disables the corresponding output event. Refer to the EVSYS - Event System for details on configuring the event system.
The RTC can take the following actions on an input event:
- Tamper (TAMPEVT): Capture the RTC counter to the timestamp register. See Tamper Detection.
Writing a one to an Event Input bit into the Event Control register (EVCTRL.xxxEI) enables the corresponding action on input event. Writing a zero to this bit disables the corresponding action on input event.