Atmel AVR XMEGA AU series User Manual

106
8331B–AVR–03/12
Atmel AVR XMEGA AU
Table 8-1 on page 106 shows the different sleep modes and the active clock domains, oscilla-
tors, and wake-up sources.
The wake-up time for the device is dependent on the sleep mode and the main clock source.
The startup time for the system clock source must be added to the wake-up time for sleep
modes where the system clock source is not kept running. For details on the startup time for the
different oscillator options, refer to ”System Clock and Clock Options” on page 83.
The content of the register file, SRAM and registers are kept during sleep. If a reset occurs dur-
ing sleep, the device will reset, start up, and execute from the reset vector.
8.3.1 Idle Mode
In idle mode the CPU and nonvolatile memory are stopped (note that any ongoing programming
will be completed), but all peripherals, including the interrupt controller, event system and DMA
controller are kept running. Any enabled interrupt will wake the device.
8.3.2 Power-down Mode
In power-down mode, all clocks, including the real-time counter clock source, are stopped. This
allows operation only of asynchronous modules that do not require a running clock. The only
interrupts that can wake up the MCU are the two-wire interface address match interrupt, asyn-
chronous port interrupts, and the USB resume interrupt.
8.3.3 Power-save Mode
Power-save mode is identical to power down, with one exception. If the real-time counter (RTC)
is enabled, it will keep running during sleep, and the device can also wake up from either an
RTC overflow or compare match interrupt.
Table 8-1. Active clock domains and wake-up sources in the different sleep modes.
Active Clock Domain Oscillators Wake-up Sources
Sleep Modes
CPU Clock Peripheral and USB Clock RTC Clock System Clock Source RTC Clock Source USB Resume Asynchronous Port Interrupts TWI Address Match Interrupts Real Time Clock Interrupts All Interrupts
Idle X X X XXXXXX
Power down X X X
Power save X XXXXX
Standby X X X X
Extended standby X X X X X X X

Atmel AVR XMEGA AU series Specifications

General

Brand	Atmel
Model	AVR XMEGA AU series
Category	Microcontrollers
Language	English