STMicroelectronics STM32F05 series User Manual

RM0091 Real-time clock (RTC)
Doc ID 018940 Rev 1 537/742
24.3.2 GPIOs controlled by the RTC
RTC_OUT, RTC_TS and RTC_TAMP1 are mapped on the same pin (PC13).
The selection of the RTC_ALARM output is performed through the RTC_TAFCR register as
follows: the PC13VALUE bit is used to select whether the RTC_ALARM output is configured
in push-pull or open drain mode.
When PC13 is not used as RTC alternate function, it can be forced in output push-pull mode
by setting the PC13MODE bit in the RTC_TAFCR. The output data value is then given by
the PC13VALUE bit. In this case, PC13 output push-pull state and data are preserved in
Standby mode.
The output mechanism follows the priority order shown in Tabl e 7 7
When PC14 and PC15 are not used as LSE oscillator, they can be forced in output push-pull
mode by setting the PC14MODE and PC15MODE bits in the RTC_TAFCR register
respectively. The output data values are then given by PC14VALUE and PC15VALUE. In
this case, the PC14 and PC15 output push-pull states and data values are preserved in
Standby mode.
The output mechanism follows the priority order shown in Tabl e 7 8 and Ta bl e 7 9 .
Table 77. RTC pin PC13 configuration
(1)
Pin
configuration
and function
RTC_ALARM
output
enabled
RTC_CALIB
output
enabled
RTC_TAMP1
input
enabled
RTC_TS
input
enabled
PC13MODE
bit
PC13VALUE
bit
RTC_ALARM
output OD
1 Don’t care Don’t care Don’t care Don’t care 0
RTC_ALARM
output PP
1 Don’t care Don’t care Don’t care Don’t care 1
RTC_CALIB
output PP
0 1 Don’t care Don’t care Don’t care Don’t care
RTC_TAMP1
input floating
0010Don’t careDon’t care
RTC_TS and
RTC_TAMP1
input floating
0011Don’t careDon’t care
RTC_TS input
floating
0001Don’t careDon’t care
Output PP
forced
00001
PC13 output
data value
Wakeup pin or
Standard GPIO
00000Don’t care
1. OD: open drain; PP: push-pull.

STMicroelectronics STM32F05 series Specifications

General

Brand	STMicroelectronics
Model	STM32F05 series
Category	Microcontrollers
Language	English