Datasheet

ii
2586D–AVR–02/06
ATtiny25/45/85
7.10 System Clock Prescaler .......................................................................................30
8 Power Management and Sleep Modes ................................................. 32
8.1 Idle Mode ................................................................................................................33
8.2 ADC Noise Reduction Mode ..................................................................................33
8.3 Power-down Mode .................................................................................................33
8.4 Power Reduction Register ......................................................................................34
8.5 Minimizing Power Consumption .............................................................................34
9 System Control and Reset .................................................................... 36
9.1 Internal Voltage Reference .....................................................................................40
9.2 Watchdog Timer .....................................................................................................41
9.3 Timed Sequences for Changing the Configuration of the Watchdog Timer ...........44
10 Interrupts ................................................................................................ 46
10.1 Interrupt Vectors in ATtiny25/45/85 ......................................................................46
11 External Interrupts ................................................................................. 48
11.1 Pin Change Interrupt Timing ................................................................................48
11.2 External Interrupts Register Description ...............................................................49
12 I/O Ports .................................................................................................. 51
12.1 Introduction ...........................................................................................................51
12.2 Ports as General Digital I/O ..................................................................................52
12.3 Alternate Port Functions .......................................................................................57
12.4 Register Description for I/O-Ports .........................................................................63
13 8-bit Timer/Counter0 with PWM ............................................................ 64
13.1 Overview ..............................................................................................................64
13.2 Timer/Counter Clock Sources ..............................................................................65
13.3 Counter Unit .........................................................................................................65
13.4 Output Compare Unit ...........................................................................................66
13.5 Compare Match Output Unit .................................................................................68
13.6 Modes of Operation ..............................................................................................69
13.7 Timer/Counter Timing Diagrams ..........................................................................73
13.8 8-bit Timer/Counter Register Description .............................................................75
14 Timer/Counter Prescaler ....................................................................... 82
15 8-bit Timer/Counter1 .............................................................................. 84
15.1 Timer/Counter1 ....................................................................................................84