22.5 Functional Description

The RTC provides a full binary-coded decimal (BCD) clock that includes century (20), year (with leap years), month, date, day, hours, minutes and seconds reported in the Time register (RTC_TIMR) and the Calendar register (RTC_CALR).

The RTC can operate in UTC mode, giving the number of seconds elapsed since a reference time defined by the user (the UTC standard—ISO 8601—reference time is the 30th of June 1972). In this mode, the time is reported on 32-bit and coded in hexadecimal format.

The valid year range is up to 2099 in Gregorian mode (or 1300 to 1499 in Persian mode).

The RTC can operate in 24-hour mode or in 12-hour mode with an AM/PM indicator.

Corrections for leap years are included (all years divisible by 4 being leap years). This is correct up to the year 2099.

The RTC can generate configurable waveforms on RTCOUT0/1 outputs.