RTC_CALALR

RTC Calendar Alarm Register

This register can only be written if the WPEN bit is cleared in the System Controller Write Protection Mode Register (SYSC_WPMR).

To change one of the DATE, MONTH fields, it is recommended to disable the field before changing the value and then re-enable it after the change has been made. This requires up to three accesses to the RTC_CALALR. The first access clears the enable corresponding to the field to change (DATEEN, MTHEN). If the field is already cleared, this access is not required. The second access performs the change of the value (DATE, MONTH). The third access is required to re-enable the field by writing 1 in DATEEN, MTHEN fields.

  0x14 32 Read/Write 0x01010000  
Parent topic: Register Summary

RTC Calendar Alarm Register

Bit  31 30 29 28 27 26 25 24  
  DATEEN   DATE[5:0]  
Access  R/W   R/W R/W R/W R/W R/W R/W  
Reset  0   0 0 0 0 0 1  
Bit  23 22 21 20 19 18 17 16  
  MTHEN     MONTH[4:0]  
Access  R/W     R/W R/W R/W R/W R/W  
Reset  0     0 0 0 0 1  
Bit  15 14 13 12 11 10 9 8  
                   
Access                   
Reset                   
Bit  7 6 5 4 3 2 1 0  
                   
Access                   
Reset                   

Bits 20:16 – MONTH[4:0]: Month Alarm

Month Alarm

This field is the alarm field corresponding to the BCD-coded month counter.

Bit 23 – MTHEN: Month Alarm Enable

Month Alarm Enable

ValueDescription
0

The month-matching alarm is disabled.
1

The month-matching alarm is enabled.

Bits 29:24 – DATE[5:0]: Date Alarm

Date Alarm

This field is the alarm field corresponding to the BCD-coded date counter.

Bit 31 – DATEEN: Date Alarm Enable

Date Alarm Enable

ValueDescription
0

The date-matching alarm is disabled.
1

The date-matching alarm is enabled.