AT91SAM datasheet(45/67 Pages) ATMEL

45 / 67 page

11100BS–ATARM–31-Jul-12

SAM4S Series [Preliminary]

10.9

Real-Time Timer

• Real-Time Timer, allowing backup of time with different accuracies

– 32-bit Free-running backup Counter

– Integrates a 16-bit programmable prescaler running on slow clock

– Alarm Register capable to generate a wake-up of the system through the Shut Down

Controller

10.10 Real Time Clock

• Low power consumption

• Full asynchronous design

• Two hundred year Gregorian and Persian calendar

• Programmable Periodic Interrupt

• Trimmable 32.7682 kHz crystal oscillator clock source

• Alarm and update parallel load

• Control of alarm and update Time/Calendar Data In

• Waveform output capability on GPIO pins in low power modes

10.11 General-Purpose Backup Registers

• Eight 32-bit backup general-purpose registers

10.12 Nested Vectored Interrupt Controller

• Thirty maskable external interrupts

• Sixteen priority levels

• Processor state automatically saved on interrupt entry, and restored on

• Dynamic reprioritizing of interrupts

• Priority grouping.

– selection of pre-empting interrupt levels and non pre-empting interrupt levels.

• Support for tail-chaining and late arrival of interrupts.

– back-to-back interrupt processing without the overhead of state saving and

restoration between interrupts.

• Processor state automatically saved on interrupt entry, and restored on interrupt exit, with no

instruction overhead.

AT91SAM Datasheet(PDF) 45 Page - ATMEL Corporation