Rtc Main Features; Figure 215. Rtc Block Diagram - ST STM32F207 Series Reference Manual

RM0033
22.2

RTC main features

The RTC unit main features are the following (see
•
Calendar with seconds, minutes, hours (12 or 24 format), day (day of week), date (day
of month), month, and year.
•
Daylight saving compensation programmable by software.
•
Two programmable alarms with interrupt function. The alarms 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.
•
Maskable interrupts/events:
–
–
–
–
–
•
Digital calibration circuit (periodic counter correction)
–
•
Timestamp function for event saving (1 event)
•
Tamper detection:
–
• 20 backup registers (80 bytes). The backup registers are reset when a tamper
detection event occurs.
•
RTC alternate function outputs (RTC_AFO):
–
–
•
RTC alternate function inputs (RTC_AFI):
–
–
Note: Refer to
on how to select RTC alternate functions (RTC_AF1 and RTC_AF2).
Alarm A
Alarm B
Wakeup interrupt
Timestamp
Tamper detection
5 ppm accuracy
1 tamper event on edge detection
AFO_CALIB: 512 Hz clock output (with an LSE frequency of 32.768 kHz). It is
routed to the device RTC_AF1 pin.
AFO_ALARM: Alarm A or Alarm B or wakeup (only one can be selected). It is
routed to the device RTC_AF1 pin.
AFI_TAMPER1: tamper event detection. It is routed to the device RTC_AF1 and
RTC_AF2 pins.
AFI_TIMESTAMP: timestamp event detection. It is routed to the device RTC_AF1
and RTC_AF2 pins.
Section 6.4.1: GPIO port mode register (GPIOx_MODER) (x = A..I)
Figure 215: RTC block
RM0033 Rev 9
Real-time clock (RTC)
diagram):
for more details
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