Datasheet

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2545F–AVR–06/05
7.9 Clock Output Buffer ................................................................................................34
7.10 Timer/Counter Oscillator ......................................................................................34
7.11 System Clock Prescaler .......................................................................................34
8 Power Management and Sleep Modes ................................................. 37
8.1 Idle Mode ................................................................................................................38
8.2 ADC Noise Reduction Mode ..................................................................................38
8.3 Power-down Mode .................................................................................................38
8.4 Power-save Mode ..................................................................................................38
8.5 Standby Mode ........................................................................................................39
8.6 Power Reduction Register ......................................................................................39
8.7 Minimizing Power Consumption .............................................................................41
9 System Control and Reset .................................................................... 43
9.1 Internal Voltage Reference .....................................................................................48
9.2 Watchdog Timer .....................................................................................................49
10 Interrupts ................................................................................................ 54
10.1 Interrupt Vectors in ATmega48 ............................................................................54
10.2 Interrupt Vectors in ATmega88 ............................................................................56
10.3 Interrupt Vectors in ATmega168 ..........................................................................59
11 External Interrupts ................................................................................. 64
11.1 Pin Change Interrupt Timing ................................................................................64
12 I/O-Ports .................................................................................................. 69
12.1 Introduction ...........................................................................................................69
12.2 Ports as General Digital I/O ..................................................................................70
12.3 Alternate Port Functions .......................................................................................74
12.4 Register Description for I/O Ports .........................................................................86
13 8-bit Timer/Counter0 with PWM ............................................................ 88
13.1 Overview ..............................................................................................................88
13.2 Timer/Counter Clock Sources ..............................................................................89
13.3 Counter Unit .........................................................................................................89
13.4 Output Compare Unit ...........................................................................................90
13.5 Compare Match Output Unit .................................................................................92
13.6 Modes of Operation ..............................................................................................93
13.7 Timer/Counter Timing Diagrams ..........................................................................97
13.8 8-bit Timer/Counter Register Description .............................................................99