Atmel Xplained Pro Evaluation Kit ATSAM4E-XPRO ATSAM4E-XPRO Fiche De Données
Codes de produits
ATSAM4E-XPRO
333
SAM4E [DATASHEET]
Atmel-11157D-ATARM-SAM4E16-SAM4E8-Datasheet_12-Jun-14
Anyway the TDERR error flag will be set again if the source of the error has not been cleared before clearing the
TDERR flag. The clearing of the source of such error can be done either by reprogramming a correct value on
RTC_CALR and/or RTC_TIMR.
TDERR flag. The clearing of the source of such error can be done either by reprogramming a correct value on
RTC_CALR and/or RTC_TIMR.
The RTC internal free running counters may automatically clear the source of TDERR due to their roll-over (i.e.,
every 10 seconds for SECONDS[3:0] field in RTC_TIMR). In this case the TDERR is held high until a clear
command is asserted by TDERRCLR bit in RTC_SCCR.
every 10 seconds for SECONDS[3:0] field in RTC_TIMR). In this case the TDERR is held high until a clear
command is asserted by TDERRCLR bit in RTC_SCCR.
16.5.6 Updating Time/Calendar
To update any of the time/calendar fields, the user must first stop the RTC by setting the corresponding field in the
Control Register (RTC_CR). Bit UPDTIM must be set to update time fields (hour, minute, second) and bit UPDCAL
must be set to update calendar fields (century, year, month, date, day).
Control Register (RTC_CR). Bit UPDTIM must be set to update time fields (hour, minute, second) and bit UPDCAL
must be set to update calendar fields (century, year, month, date, day).
The ACKUPD bit is automatically set within a second after setting the UPDTIM and/or UPDCAL bit (meaning one
second is the maximum duration of the polling or wait for interrupt period). Once ACKUPD is set, it is mandatory to
clear this flag by writing the corresponding bit in the RTC_SCCR, after which the user can write to the Time
Register, the Calendar Register, or both.
second is the maximum duration of the polling or wait for interrupt period). Once ACKUPD is set, it is mandatory to
clear this flag by writing the corresponding bit in the RTC_SCCR, after which the user can write to the Time
Register, the Calendar Register, or both.
Once the update is finished, the user must reset (0) UPDTIM and/or UPDCAL in the RTC_CR.
When entering programming mode of the calendar fields, the time fields remain enabled. When entering the
programming mode of the time fields, both time and calendar fields are stopped. This is due to the location of the
calendar logic circuity (downstream for low-power considerations). It is highly recommended to prepare all the
fields to be updated before entering programming mode. In successive update operations, the user must wait at
least one second after resetting the UPDTIM/UPDCAL bit in the RTC_CR before setting these bits again. This is
done by waiting for the SEC flag in the RTC_SR before setting UPDTIM/UPDCAL bit. After resetting
UPDTIM/UPDCAL, the SEC flag must also be cleared.
programming mode of the time fields, both time and calendar fields are stopped. This is due to the location of the
calendar logic circuity (downstream for low-power considerations). It is highly recommended to prepare all the
fields to be updated before entering programming mode. In successive update operations, the user must wait at
least one second after resetting the UPDTIM/UPDCAL bit in the RTC_CR before setting these bits again. This is
done by waiting for the SEC flag in the RTC_SR before setting UPDTIM/UPDCAL bit. After resetting
UPDTIM/UPDCAL, the SEC flag must also be cleared.