Atmel Evaluation Kit AT91SAM9M10-G45-EK AT91SAM9M10-G45-EK Data Sheet
Product codes
AT91SAM9M10-G45-EK
87
SAM9M10 [DATASHEET]
6355F–ATARM–12-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.
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.
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