Datasheet

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7593L–AVR–09/12
AT90USB64X/128X
7.10 PLL ......................................................................................................................49
8 Power management and sleep modes ................................................. 51
8.1 Idle mode ...............................................................................................................52
8.2 ADC noise reduction mode ...................................................................................52
8.3 Power-down mode ................................................................................................52
8.4 Power-save mode .................................................................................................52
8.5 Standby mode .......................................................................................................53
8.6 Extended Standby mode .......................................................................................53
8.7 Power Reduction Register .....................................................................................54
8.8 Minimizing power consumption .............................................................................55
9 System control and reset ...................................................................... 57
9.1 Resetting the AVR .................................................................................................57
9.2 Reset sources .......................................................................................................57
9.3 Power-on reset ......................................................................................................58
9.4 External reset ........................................................................................................59
9.5 Brown-out detection ..............................................................................................60
9.6 Watchdog reset .....................................................................................................61
9.7 Internal voltage reference ......................................................................................62
9.8 Watchdog timer .....................................................................................................63
10 Interrupts ................................................................................................ 68
10.1 Interrupt vectors in AT90USB64/128 ...................................................................68
11 I/O-ports .................................................................................................. 71
11.1 Introduction ..........................................................................................................71
11.2 Ports as general digital I/O ..................................................................................72
11.3 Alternate port functions .......................................................................................76
11.4 Register description for I/O-ports ........................................................................89
12 External interrupts ................................................................................. 92
13 Timer/Counter0, Timer/Counter1, and Timer/Counter3 prescalers ... 96
13.1 Internal clock source ...........................................................................................96
13.2 Prescaler reset ....................................................................................................96
13.3 External clock source ..........................................................................................96
13.4 GTCCR – General Timer/Counter Control Register ............................................97
14 8-bit Timer/Counter0 with PWM ............................................................ 98
14.1 Overview .............................................................................................................98