18.6.1 RTC Control Register
This register can only be written if the WPEN bit is cleared in the System Controller Write Protection Mode register (SYSC_WPMR).
| Name: | RTC_CR |
| Offset: | 0x00 |
| Reset: | 0x00000000 |
| Property: | Read/Write |
| Bit | 31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | |
| Access | |||||||||
| Reset |
| Bit | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 | |
| CALEVSEL[1:0] | |||||||||
| Access | R/W | R/W | |||||||
| Reset | 0 | 0 | |||||||
| Bit | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | |
| TIMEVSEL[1:0] | |||||||||
| Access | R/W | R/W | |||||||
| Reset | 0 | 0 | |||||||
| Bit | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | |
| UPDCAL | UPDTIM | ||||||||
| Access | R/W | R/W | |||||||
| Reset | 0 | 0 |
Bits 17:16 – CALEVSEL[1:0] Calendar Event Selection
The event that generates the flag CALEV in RTC_SR depends on the value of CALEVSEL
In UTC mode, this field has no effect on RTC_SR.
| Value | Name | Description |
|---|---|---|
| 0 | WEEK | Week change (every Monday at time 00:00:00) |
| 1 | MONTH | Month change (every 01 of each month at time 00:00:00) |
| 2 | YEAR | Year change (every January 1 at time 00:00:00) |
| 3 | YEAR | Reserved |
Bits 9:8 – TIMEVSEL[1:0] Time Event Selection
The event that generates the flag TIMEV in RTC_SR depends on the value of TIMEVSEL.
In UTC mode, this field has no effect on RTC_SR.
| Value | Name | Description |
|---|---|---|
| 0 | MINUTE | Minute change |
| 1 | HOUR | Hour change |
| 2 | MIDNIGHT | Every day at midnight |
| 3 | NOON | Every day at noon |
Bit 1 – UPDCAL Update Request Calendar Register
Calendar counting consists of day, date, month, year and century counters. Calendar counters can be programmed once this bit is set and acknowledged by the RTC_SR.ACKUPD bit.
In UTC mode, both UPDTIM and UPDCAL must be set to '1' in order to update the UTC time value.
| Value | Name | Description |
|---|---|---|
| 0 | CLOSE_UPDATE | No effect or, if UPDCAL has been previously written to 1, stops the update procedure. |
| 1 | START_UPDATE | Stops the RTC calendar counting. |
Bit 0 – UPDTIM Update Request Time Register
Time counting consists of second, minute and hour counters. Time counters can be programmed once this bit is set and acknowledged by the RTC_SR.ACKUPD bit.
In UTC mode, both UPDTIM and UPDCAL must be set to '1' in order to update the UTC time value.
| Value | Name | Description |
|---|---|---|
| 0 | CLOSE_UPDATE | No effect or, if UPDTIM has been previously written to 1, stops the update procedure. |
| 1 | START_UPDATE | Stops the RTC time counting. |