Atmel ARM-Based Evaluation Kit for SAM4S16C, 32-Bit ARM® Cortex® Microcontroller ATSAM4S-WPIR-RD ATSAM4S-WPIR-RD Data Sheet

SAM4S Series [DATASHEET]

Atmel-11100G-ATARM-SAM4S-Datasheet_27-May-14

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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.
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.
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.
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.
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.

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Ultra Low Power Consumption

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Full Asynchronous Design

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Gregorian Calendar up to 2099 or Persian Calendar

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Programmable Periodic Interrupt

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Safety/security features:

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Valid Time and Date Programmation Check

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On-The-Fly Time and Date Validity Check

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Crystal Oscillator Clock Calibration

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Waveform Generation

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