Datasheet

ii
8272E–AVR–04/2013
ATmega164A/PA/324A/PA/644A/PA/1284/P
9.2Clock Sources .........................................................................................................31
9.3Low Power Crystal Oscillator ...................................................................................33
9.4Full swing Crystal Oscillator ....................................................................................34
9.5Low Frequency Crystal Oscillator ............................................................................35
9.6Calibrated Internal RC Oscillator .............................................................................36
9.7128kHz internal oscillator ........................................................................................37
9.8External clock ..........................................................................................................38
9.9Timer/Counter Oscillator .........................................................................................38
9.10Clock Output Buffer ...............................................................................................39
9.11System Clock Prescaler ........................................................................................39
9.12Register description ...............................................................................................40
10 Power management and sleep modes ................................................. 42
10.1Overview ...............................................................................................................42
10.2Sleep Modes .........................................................................................................42
10.3BOD disable
(1)
.......................................................................................................43
10.4Idle mode ...............................................................................................................43
10.5ADC Noise Reduction mode .................................................................................43
10.6Power-down mode ................................................................................................44
10.7Power-save mode .................................................................................................44
10.8Standby mode .......................................................................................................44
10.9Extended Standby mode .......................................................................................44
10.10Power Reduction Register ...................................................................................45
10.11Minimizing Power Consumption ..........................................................................45
10.12Register description .............................................................................................47
11 System Control and Reset .................................................................... 50
11.1Resetting the AVR .................................................................................................50
11.2Internal Voltage Reference ....................................................................................54
11.3Watchdog Timer ....................................................................................................55
11.4Register description ...............................................................................................58
12 Interrupts ................................................................................................ 61
12.1Overview ...............................................................................................................61
12.2Interrupt Vectors in ATmega164A/164PA/324A/324PA/644A/644PA/1284/1284P ..
61
12.3Register description ...............................................................................................65
13 External Interrupts ................................................................................. 67