Datasheet

87
SAM9M10 [DATASHEET]
6355FATARM12-Mar-13
14. Real-time Clock (RTC)
14.1 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.
14.2 Embedded Characteristics
Low power consumption
Full asynchronous design
Two hundred year calendar
Programmable Periodic Interrupt
Alarm and update parallel load
Control of alarm and update Time/Calendar Data In
14.3 Block Diagram
Figure 14-1. RTC Block Diagram
Bus Interface
32768 Divider
Time
Crystal Oscillator: SLCK
Bus Interface
Date
RTC Interrupt
Entry
Control
Interrupt
Control