Figure 19. Rtc Simplified Block Diagram - ST STM32F101 Series Reference Manual

RM0008
time is incremented at the TR_CLK rate and compared with a programmable date (stored in
the RTC_ALR register) in order to generate an alarm interrupt, if enabled in the RTC_CR
control register.

Figure 19. RTC simplified block diagram

PCLK1
RTCCLK
RTC_PRL
Reload
RTC_DIV
rising
edge
RTC prescaler
powered in Standby
WKUP pin
Backup domain
32-bit programmable
counter
TR_CLK
RTC_CNT
=
RTC_ALR
powered in Standby
APB1 bus
APB1 interface
RTC_Second
RTC_Overflow
RTC_Alarm
RTC_Alarm
WKP_STDBY
Real-time clock (RTC)
not powered in Standby
RTC_CR
SECF
SECIE
OWF
OWIE
ALRF
ALRIE
not powered in Standby
NVIC interrupt
controller
not powered in Standby
exit from
Standby mode
powered in Standby
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