Atmel Evaluation Kit for the SAM4E Series of Flash Microcontrollers ATSAM4E-EK ATSAM4E-EK Data Sheet
Product codes
ATSAM4E-EK
SAM4E [DATASHEET]
Atmel-11157D-ATARM-SAM4E16-SAM4E8-Datasheet_12-Jun-14
330
16.
Real-time Clock (RTC)
16.1
Description
The Real-time Clock (RTC) peripheral is designed for very low power consumption. For optimal functionality, the
RTC requires an accurate external 32.768 kHz clock, which can be provided by a crystal oscillator.
RTC requires an accurate external 32.768 kHz clock, which can be provided by a crystal oscillator.
It combines a complete time-of-day clock with alarm and a two-hundred-year Gregorian or Persian calendar,
complemented by a programmable periodic interrupt. The alarm and calendar registers are accessed by a 32-bit
data bus.
complemented by a programmable periodic interrupt. The alarm and calendar registers are accessed by a 32-bit
data bus.
The time and calendar values are coded in binary-coded decimal (BCD) format. The time format can be 24-hour
mode or 12-hour mode with an AM/PM indicator.
mode or 12-hour mode with an AM/PM indicator.
Updating time and calendar fields and configuring the alarm fields are performed by a parallel capture on the 32-bit
data bus. An entry control is performed to avoid loading registers with incompatible BCD format data or with an
incompatible date according to the current month/year/century.
data bus. An entry control is performed to avoid loading registers with incompatible BCD format data or with an
incompatible date according to the current month/year/century.
A clock divider calibration circuitry enables to compensate crystal oscillator frequency inaccuracy.
An RTC output can be programmed to generate several waveforms, including a prescaled clock derived from
32.768 kHz.
32.768 kHz.
16.2
Embedded Characteristics
Ultra Low Power Consumption
Full Asynchronous Design
Gregorian Calendar up to 2099 or Persian Calendar
Programmable Periodic Interrupt
Safety/security features:
̶
Valid Time and Date Programmation Check
̶
On-The-Fly Time and Date Validity Check
Crystal Oscillator Clock Calibration
Waveform Generation
Register Write Protection