Datasheet

13.3. Default Clock Source..................................................................................................................54
13.4. Crystal Oscillator........................................................................................................................ 54
13.5. Low-frequency Crystal Oscillator................................................................................................55
13.6. External RC Oscillator................................................................................................................ 56
13.7. Calibrated Internal RC Oscillator................................................................................................56
13.8. External Clock............................................................................................................................ 57
13.9. Timer/Counter Oscillator.............................................................................................................58
13.10. Register Description...................................................................................................................58
14. Power Management and Sleep Modes................................................................... 61
14.1. Sleep Modes...............................................................................................................................61
14.2. Idle Mode....................................................................................................................................62
14.3. ADC Noise Reduction Mode.......................................................................................................62
14.4. Power-down Mode......................................................................................................................62
14.5. Power-save Mode.......................................................................................................................62
14.6. Standby Mode............................................................................................................................ 63
14.7. Extended Standby Mode............................................................................................................ 63
14.8. Minimizing Power Consumption................................................................................................. 63
14.9. Register Description................................................................................................................... 65
15. System Control and Reset.......................................................................................67
15.1. Resetting the AVR...................................................................................................................... 67
15.2. Reset Sources............................................................................................................................67
15.3. Internal Voltage Reference.........................................................................................................71
15.4. Watchdog Timer......................................................................................................................... 71
15.5. Timed Sequences for Changing the Configuration of the Watchdog Timer............................... 72
15.6. Register Description................................................................................................................... 73
16. Interrupts................................................................................................................. 77
16.1. Interrupt Vectors in ATmega64A.................................................................................................77
16.2. Register Description................................................................................................................... 82
17. External Interrupts................................................................................................... 85
17.1. Register Description................................................................................................................... 85
18. I/O Ports.................................................................................................................. 92
18.1. Overview.....................................................................................................................................92
18.2. Ports as General Digital I/O........................................................................................................93
18.3. Alternate Port Functions.............................................................................................................96
18.4. Register Description..................................................................................................................111
19. Timer/Counter3, Timer/Counter2, and Timer/Counter1 Prescalers....................... 134
19.1. Overview...................................................................................................................................134
19.2. Internal Clock Source............................................................................................................... 134
19.3. Prescaler Reset........................................................................................................................134
19.4. External Clock Source..............................................................................................................134
19.5. Register Description................................................................................................................. 135
20. 16-bit Timer/Counter (Timer/Counter1 and Timer/Counter3).................................137
Atmel ATmega64A [DATASHEET]
Atmel-8160E-ATmega64A_Datasheet_Complete-09/2015
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