Datasheet

SAM9G45 [DATASHEET]
Atmel-6438O-ATARM-SAM9G45-Datasheet_08-Dec-15
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13. Real-time Clock (RTC)
13.1 Description
The Real-time Clock (RTC) peripheral is designed for very low power consumption.
It combines a complete time-of-day clock with alarm and a two-hundred-year Gregorian 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.
13.2 Embedded Characteristics
 Low power consumption
 Full asynchronous design
 Two hundred year calendar
 Programmable Periodic Interrupt
 Alarm and update parallel load
13.3 Block Diagram
Figure 13-1. RTC Block Diagram
Bus Interface
32768 Divider
Time
Crystal Oscillator: SLCK
Bus Interface
Date
RTC Interrupt
Entry
Control
Interrupt
Control