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8331B–AVR–03/12
Atmel AVR XMEGA AU
System Clock and Clock Options ......................................................... 83
System Clock Selection and Prescalers ..........................................................87
DFLL 2MHz and DFLL 32MHz ........................................................................89
PLL and External Clock Source Failure Monitor ..............................................90
Register Description – DFLL32M/DFLL2M ....................................................101
Register Summary - DFLL32M/DFLL2M .......................................................104
Oscillator Failure Interrupt Vector Summary .................................................104
Power Management and Sleep Modes ............................................... 105
Minimizing Power Consumption ....................................................................107
Register Description – Power Reduction .......................................................109
Register Summary – Power Reduction .........................................................112
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