ATMEGA8U2_14 Datasheet, PDF (305/310 Pages) ATMEL Corporation – 125 Powerful Instructions – Most Single Clock Cycle Execution

7799D–AVR–11/10
ATmega8U2/16U2/32U2
14.1Overview ................................................................................................................88
14.2Internal Clock Source ............................................................................................88
14.3Prescaler Reset .....................................................................................................88
14.4External Clock Source ...........................................................................................88
14.5Register Description ..............................................................................................89
15 8-bit Timer/Counter0 with PWM ............................................................ 91
15.1Features ................................................................................................................91
15.2Overview ................................................................................................................91
15.3Timer/Counter Clock Sources ...............................................................................92
15.4Counter Unit ..........................................................................................................92
15.5Output Compare Unit .............................................................................................93
15.6Compare Match Output Unit ..................................................................................95
15.7Modes of Operation ...............................................................................................96
15.8Timer/Counter Timing Diagrams .........................................................................100
15.9Register Description ............................................................................................102
16 16-bit Timer/Counter 1 with PWM ....................................................... 108
16.1Features ..............................................................................................................108
16.2Overview ..............................................................................................................108
16.3Accessing 16-bit Registers ..................................................................................110
16.4Timer/Counter Clock Sources .............................................................................113
16.5Counter Unit ........................................................................................................114
16.6Input Capture Unit ...............................................................................................115
16.7Output Compare Units .........................................................................................117
16.8Compare Match Output Unit ................................................................................119
16.9Modes of Operation .............................................................................................120
16.10Timer/Counter Timing Diagrams .......................................................................127
16.11Register Description ..........................................................................................129
17 SPI – Serial Peripheral Interface ......................................................... 138
17.1Features ..............................................................................................................138
17.2Overview ..............................................................................................................138
17.3SS Pin Functionality ............................................................................................142
17.4Data Modes .........................................................................................................143
17.5Register Description ............................................................................................145
18 USART ................................................................................................... 148
18.1Features ..............................................................................................................148
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