Real-time clock (RTC)
RM0090
826/1731
DocID018909 Rev 11
26.6.20 RTC backup registers (RTC_BKPxR)
Address offset: 0x50 to 0x9C
Backup domain reset value: 0x0000 0000
System reset: not affected
26.6.21 RTC
register
map
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
BKP[31:16]
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
BKP[15:0]
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
w
rw
rw
Bits 31:0 BKP[31:0]
The application can write or read data to and from these registers.
They are powered-on by V
BAT
when V
DD
is switched off, so that they are not reset by
System reset, and their contents remain valid when the device operates in low-power mode.
This register is reset on a tamper detection event, as long as TAMPxF=1.
Table 120. RTC register map and reset values
Offset
Register
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
0x00
RTC_TR
Reserved
PM
HT
[1:0]
HU[3:0]
Re
se
rv
e
d
MNT[2:0]
MNU[3:0]
Re
se
rv
e
d
ST[2:0]
SU[3:0]
Reset value
0
0
0 0 0 0 0
0
0
0 0 0 0 0
0 0 0 0
0
0
0
0x04
RTC_DR
Reserved
YT[3:0]
YU[3:0]
WDU[2:0]
MT
MU[3:0]
Reserved
DT
[1:0]
DU[3:0]
Reset value
0
0
1
0 0 0 0 1
0 0 0
0
0
1
0x08
RTC_CR
Reserved
COE
OSEL
[1:0]
PO
L
CO
SEL
BK
P
SUB1
H
ADD1
H
TSIE
WUTI
E
AL
R
B
IE
AL
R
A
IE
TSE
WUTE
ALRB
E
ALRA
E
DCE
FMT
BY
PSHA
D
RE
F
C
K
O
N
TSEDG
E
WCKSEL
[2:0]
Reset value
0
0
0
0 0 0 0 0
0
0
0
0 0 0 0 0 0 0 0 0 0
0
0
0
0x0C
RTC_ISR
Reserved
TA
M
P
2
F
TA
M
P
1
F
TSO
V
F
TS
F
WUT
F
AL
R
B
F
AL
R
A
F
INI
T
INI
T
F
RSF
INIT
S
SHPF
WUT
W
F
AL
R
B
W
F
AL
R
A
WF
Reset value
0
0
0 0 0 0 0 0 0 0 0 0
1
0
1
0x10
RTC_PRER
Reserved
PREDIV_A[6:0]
Reserved
PREDIV_S[14:0]
Reset value
1
1
1 1 1 1 1
0 0
0 0 0 0 0 1 1 1 1 1
1
1
1
0x14
RTC_WUTR
Reserved
WUT[15:0]
Reset value
1
1
1
1 1 1 1 1 1 1 1 1 1
1
1
1
0x18
RTC_CALIBR
Reserved
DCS
Reserved
DC[4:0]
Reset value
0
0 0
0
0
0