Datasheet

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8011Q–AVR–02/2013
ATmega164P/324P/644P
6.5 Low Frequency Crystal Oscillator ...........................................................................34
6.6 Calibrated Internal RC Oscillator ............................................................................36
6.7 128 kHz Internal Oscillator .....................................................................................37
6.8 External Clock ........................................................................................................37
6.9 Timer/Counter Oscillator ........................................................................................38
6.10 Clock Output Buffer ..............................................................................................38
6.11 System Clock Prescaler .......................................................................................38
6.12 Register Description .............................................................................................40
7 Power Management and Sleep Modes ................................................. 42
7.1 Overview ................................................................................................................42
7.2 Sleep Modes ..........................................................................................................42
7.3 BOD Disable ...........................................................................................................43
7.4 Idle Mode ................................................................................................................43
7.5 ADC Noise Reduction Mode ..................................................................................43
7.6 Power-down Mode .................................................................................................44
7.7 Power-save Mode ..................................................................................................44
7.8 Standby Mode ........................................................................................................44
7.9 Extended Standby Mode ........................................................................................44
7.10 Power Reduction Register ....................................................................................45
7.11 Minimizing Power Consumption ...........................................................................45
7.12 Register Description .............................................................................................47
8 System Control and Reset .................................................................... 50
8.1 Resetting the AVR ..................................................................................................50
8.2 Reset Sources ........................................................................................................50
8.3 Power-on Reset ......................................................................................................51
8.4 External Reset ........................................................................................................52
8.5 Brown-out Detection ...............................................................................................53
8.6 Watchdog Reset .....................................................................................................53
8.7 Internal Voltage Reference .....................................................................................54
8.8 Watchdog Timer .....................................................................................................55
8.9 Register Description ...............................................................................................58
9 Interrupts ................................................................................................ 61
9.1 Overview ................................................................................................................61
9.2 Interrupt Vectors in ATmega164P/324P/644P .......................................................61
9.3 Register Description ...............................................................................................65