DocID025202 Rev 7
740/1080
RM0365
Real-time clock (RTC)
764
Backup domain reset value: 0x0000 0000
System reset: 0x0000 0000 when BYPSHAD = 0. Not affected when BYPSHAD = 1.
27.6.2
RTC date register (RTC_DR)
The RTC_DR is the calendar date shadow register. This register must be written in
initialization mode only. Refer to
Calendar initialization and configuration on page 729
and
Reading the calendar on page 730
This register is write protected. The write access procedure is described in
Address offset: 0x04
Backup domain reset value: 0x0000 2101
System reset: 0x0000 2101 when BYPSHAD = 0. Not affected when BYPSHAD = 1.
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
Res.
Res.
Res.
Res.
Res.
Res.
Res.
Res.
Res.
PM
HT[1:0]
HU[3:0]
rw
rw
rw
rw
rw
rw
rw
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
Res.
MNT[2:0]
MNU[3:0]
Res.
ST[2:0]
SU[3:0]
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
Bits 31-23 Reserved, must be kept at reset value
Bit 22
PM
:
AM/PM notation
0: AM or 24-hour format
1: PM
Bits 21:20
HT[1:0]
: Hour tens in BCD format
Bits 19:16
HU[3:0]
: Hour units in BCD format
Bit 15 Reserved, must be kept at reset value.
Bits 14:12
MNT[2:0]
: Minute tens in BCD format
Bits 11:8
MNU[3:0]
: Minute units in BCD format
Bit 7 Reserved, must be kept at reset value.
Bits 6:4
ST[2:0]
: Second tens in BCD format
Bits 3:0
SU[3:0]
: Second units in BCD format
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
Res.
Res.
Res.
Res.
Res.
Res.
Res.
Res.
YT[3:0]
YU[3:0]
rw
rw
rw
rw
rw
rw
rw
rw
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
WDU[2:0]
MT
MU[3:0]
Res.
Res.
DT[1:0]
DU[3:0]
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw
rw