Rtc Main Features - ST STM32L4x6 Reference Manual

Real-time clock (RTC)
34.2

RTC main features

The RTC unit main features are the following (see
•
Calendar with subseconds, seconds, minutes, hours (12 or 24 format), day (day of
week), date (day of month), month, and year.
•
Daylight saving compensation programmable by software.
•
Programmable alarm with interrupt function. The alarm can be triggered by any
combination of the calendar fields.
•
Automatic wakeup unit generating a periodic flag that triggers an automatic wakeup
interrupt.
• Reference clock detection: a more precise second source clock (50 or 60 Hz) can be
used to enhance the calendar precision.
•
Accurate synchronization with an external clock using the subsecond shift feature.
•
Digital calibration circuit (periodic counter correction): 0.95 ppm accuracy, obtained in a
calibration window of several seconds
•
Time-stamp function for event saving
•
Tamper detection event with configurable filter and internal pull-up
•
Maskable interrupts/events:
–
–
–
–
–
•
32 backup registers.
1064/1693
Alarm A
Alarm B
Wakeup interrupt
Time-stamp
Tamper detection
DocID024597 Rev 3
Figure 351: RTC block
RM0351
diagram):