RTC control register
| WUCKSEL | Wakeup clock selection |
| TSEDGE | Time-stamp event active edge TSE must be reset when TSEDGE is changed to avoid unwanted TSF setting. |
| REFCKON | RTC_REFIN reference clock detection enable (50 or 60Hz) Note: PREDIV_S must be 0x00FF. |
| BYPSHAD | Bypass the shadow registers Note: If the frequency of the APB clock is less than seven times the frequency of RTCCLK, BYPSHAD must be set to 1. |
| FMT | Hour format |
| ALRAE | Alarm A enable |
| ALRBE | Alarm B enable |
| WUTE | Wakeup timer enable |
| TSE | timestamp enable |
| ALRAIE | Alarm A interrupt enable |
| ALRBIE | Alarm B interrupt enable |
| WUTIE | Wakeup timer interrupt enable |
| TSIE | Time-stamp interrupt enable |
| ADD1H | Add 1 hour (summer time change) When this bit is set outside initialization mode, 1 hour is added to the calendar time. This bit is always read as 0. |
| SUB1H | Subtract 1 hour (winter time change) When this bit is set outside initialization mode, 1 hour is subtracted to the calendar time if the current hour is not 0. This bit is always read as 0. Setting this bit has no effect when current hour is 0. |
| BKP | Backup This bit can be written by the user to memorize whether the daylight saving time change has been performed or not. |
| COSEL | Calibration output selection When COE=1, this bit selects which signal is output on RTC_CALIB. These frequencies are valid for RTCCLK at 32.768 kHz and prescalers at their default values (PREDIV_A=127 and PREDIV_S=255). Refer to Section24.3.15: Calibration clock output |
| POL | Output polarity This bit is used to configure the polarity of RTC_ALARM output |
| OSEL | Output selection These bits are used to select the flag to be routed to RTC_ALARM output |
| COE | Calibration output enable This bit enables the RTC_CALIB output |
| ITSE | timestamp on internal event enable |