Datasheet

ii
8011K–AVR–09/08
ATmega164P/324P/644P
8.6 Calibrated Internal RC Oscillator ............................................................................37
8.7 128 kHz Internal Oscillator .....................................................................................38
8.8 External Clock ........................................................................................................38
8.9 Timer/Counter Oscillator ........................................................................................39
8.10 Clock Output Buffer ..............................................................................................39
8.11 System Clock Prescaler .......................................................................................39
8.12 Register Description .............................................................................................41
9 Power Management and Sleep Modes ................................................. 43
9.1 Overview ................................................................................................................43
9.2 Sleep Modes ..........................................................................................................43
9.3 BOD Disable ...........................................................................................................44
9.4 Idle Mode ................................................................................................................44
9.5 ADC Noise Reduction Mode ..................................................................................44
9.6 Power-down Mode .................................................................................................45
9.7 Power-save Mode ..................................................................................................45
9.8 Standby Mode ........................................................................................................45
9.9 Extended Standby Mode ........................................................................................45
9.10 Power Reduction Register ....................................................................................46
9.11 Minimizing Power Consumption ...........................................................................46
9.12 Register Description .............................................................................................48
10 System Control and Reset .................................................................... 51
10.1 Internal Voltage Reference ...................................................................................55
10.2 Watchdog Timer ...................................................................................................56
10.3 Register Description .............................................................................................59
11 Interrupts ................................................................................................ 62
11.1 Overview ..............................................................................................................62
11.2 Interrupt Vectors in ATmega164P/324P/644P .....................................................62
11.3 Register Description .............................................................................................66
12 External Interrupts ................................................................................. 68
12.1 Overview ..............................................................................................................68
12.2 Register Description .............................................................................................68
13 I/O-Ports .................................................................................................. 73
13.1 Overview ..............................................................................................................73
13.2 Ports as General Digital I/O ..................................................................................74