ST STM32F31xx User Manual

Real-time clock (RTC)
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19.1.5 RTC_AlarmTypeDef
RTC_AlarmTypeDef is defined in the stm32f30x_rtc.h
Data Fields
 RTC_TimeTypeDef RTC_AlarmTime
 uint32_t RTC_AlarmMask
 uint32_t RTC_AlarmDateWeekDaySel
 uint8_t RTC_AlarmDateWeekDay
Field Documentation
 RTC_TimeTypeDef RTC_AlarmTypeDef::RTC_AlarmTime
 Specifies the RTC Alarm Time members.
 uint32_t RTC_AlarmTypeDef::RTC_AlarmMask
 Specifies the RTC Alarm Masks. This parameter can be a value of
RTC_AlarmMask_Definitions
 uint32_t RTC_AlarmTypeDef::RTC_AlarmDateWeekDaySel
 Specifies the RTC Alarm is on Date or WeekDay. This parameter can be a value
of RTC_AlarmDateWeekDay_Definitions
 uint8_t RTC_AlarmTypeDef::RTC_AlarmDateWeekDay
 Specifies the RTC Alarm Date/WeekDay. If the Alarm Date is selected, this
parameter must be set to a value in the 1-31 range. If the Alarm WeekDay is
selected, this parameter can be a value of RTC_WeekDay_Definitions
19.2 RTC Firmware driver API description
The following section lists the various functions of the RTC library.
19.2.1 RTC Operating Condition
The real-time clock (RTC) and the RTC backup registers can be powered from the VBAT
voltage when the main VDD supply is powered off. To retain the content of the RTC backup
registers and supply the RTC when VDD is turned off, VBAT pin can be connected to an
optional standby voltage supplied by a battery or by another source.
To allow the RTC to operate even when the main digital supply (VDD) is turned off, the
VBAT pin powers the following blocks:
1. The RTC
2. The LSE oscillator
3. PC13 to PC15 I/Os (when available)
When the backup domain is supplied by VDD (analog switch connected to VDD), the
following functions are available:
1. PC14 and PC15 can be used as either GPIO or LSE pins
2. PC13 can be used as a GPIO or as the RTC_AF pin
When the backup domain is supplied by VBAT (analog switch connected to VBAT
because VDD is not present), the following functions are available:

ST STM32F31xx Specifications

General

Brand	ST
Model	STM32F31xx
Category	Microcontrollers
Language	English