RM0033 Rev 9 583/1381
RM0033 Real-time clock (RTC)
597
22.6 RTC registers
Refer to Section 1.1: List of abbreviations for registers for registers for a list of abbreviations
used in register descriptions.
The peripheral registers have to be accessed by words (32 bits).
22.6.1 RTC time register (RTC_TR)
The RTC_TR is the calendar time shadow register. This register must be written in
initialization mode only. Refer to
Calendar initialization and configuration on page 575 and
Reading the calendar on page 576.
Address offset: 0x00
Backup domain reset value: 0x0000 0000
System reset: 0x0000 0000 before the RSF flag is set, then the correct value is available.
Note: This register is write protected. The write access procedure is described in RTC register
write protection on page 574.
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16
Reserved
PM HT[1:0] HU[3:0]
rw rw rw rw rw rw rw
1514131211109876543210
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 31-24 Reserved
Bit 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
Bit 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