Real-time clock (RTC) RM0440
1542/2126 RM0440 Rev 4
The triggers outputs can be used as triggers for other peripherals.
35.3.3 GPIOs controlled by the RTC and TAMP
The GPIOs included in the Battery Backup Domain (V
BAT
) are directly controlled by the
peripherals providing functions on these I/Os, whatever the GPIO configuration.
Both RTC and TAMP peripherals provide functions on these I/Os (refer to Section 36:
Tamper and backup registers (TAMP)).
RTC_OUT1, RTC_TS and TAMP_IN1 are mapped on the same pin (PC13). The RTC and
TAMP functions mapped on PC13 are available in all low-power modes and in V
BAT
mode.
The output mechanism follows the priority order shown in Table 331.
Table 330. RTC interconnection
Signal name Source/destination
rtc_its
From power controller (PWR): main power loss/switch to V
BAT
detection
output
rtc_tamp_evt From TAMP peripheral: tamp_evt
rtc_calovf To TAMP peripheral: tamp_itamp5
Table 331. PC13 configuration
(1)
PC13 Pin function
OSEL[1:0]
(ALARM output enable)
TAMPOE
(TAMPER output enable)
COE
(CALIB output enable)
OUT2EN
TAMPALRM_TYPE
TAMPALRM_PU
TAMP1E
(TAMP_IN1 input enable)
TSE
(RTC_TS input enable)
TAMPALRM output
Push-Pull
01 or
10 or
11
0
Don’t
care
Don’t
care
00
Don’t
care
Don’t
care
00 1
01 or
10 or
11
1