Module rp2040_hal::rtc

Real time clock functionality

A RealTimeClock can be configured with an initial DateTime. Afterwards the clock will track time automatically. The current DateTime can be retrieved by RealTimeClock::now().

With the chrono feature enabled, the following types will be alias for chrono types:

• DateTime: chrono::NaiveDateTime
• DayOfWeek: chrono::Weekday

Notes

There are some things to take into account. As per the datasheet:

• Day of week: The RTC will not compute the correct day of the week; it will only increment the existing value.
  • With the chrono feature, the day of week is calculated by chrono and should be correct. The value from the rp2040 itself is not used.
• Leap year: If the current year is evenly divisible by 4, a leap year is detected, then Feb 28th is followed by Feb 29th instead of March 1st.
  • There are cases where this is incorrect, e.g. century years have no leap day, but the chip will still add a Feb 29th.
  • To disable leap year checking and never have a Feb 29th, call RealTimeClock::set_leap_year_check(false).

Other limitations:

• Leap seconds: The rp2040 will not take leap seconds into account
  • With the chrono feature, leap seconds will be silently handled by chrono. This means there might be a slight difference between the value of RealTimeClock::now() and adding 2 times together in code.

Structs

• DateTime
  Structure containing date and time information
• DateTimeFilter
  A filter used for RealTimeClock::schedule_alarm.
• RealTimeClock
  A reference to the real time clock of the system

Enums

• DateTimeError
  Errors regarding the DateTime and DateTimeFilter structs.
• DayOfWeek
  A day of the week
• RtcError
  Errors that can occur on methods on RtcClock