ATMEGA88V_14 Datasheet, PDF (372/377 Pages) ATMEL Corporation – High endurance non-volatile memory segments

2545T–AVR–05/11
ATmega48/88/168
18.3Timer/counter clock sources ...............................................................................141
18.4Counter unit .........................................................................................................141
18.5Output compare unit ............................................................................................142
18.6Compare match output unit .................................................................................144
18.7Modes of operation ..............................................................................................145
18.8Timer/counter timing diagrams ............................................................................149
18.9Asynchronous operation of Timer/Counter2 ........................................................151
18.10Timer/counter prescaler ....................................................................................152
18.11Register description ...........................................................................................153
19 SPI – Serial peripheral interface ......................................................... 161
19.1Features ..............................................................................................................161
19.2Overview .............................................................................................................161
19.3SS pin functionality ..............................................................................................166
19.4Data modes .........................................................................................................166
19.5Register description .............................................................................................168
20 USART0 ................................................................................................. 171
20.1Features ..............................................................................................................171
20.2Overview .............................................................................................................171
20.3Clock generation .................................................................................................172
20.4Frame formats .....................................................................................................175
20.5USART initialization .............................................................................................176
20.6Data transmission – The USART transmitter ......................................................179
20.7Data reception – The USART receiver ................................................................181
20.8Asynchronous data reception ..............................................................................185
20.9Multi-processor communication mode .................................................................188
20.10Register description ...........................................................................................190
20.11Examples of baud rate setting ...........................................................................194
21 USART in SPI mode ............................................................................. 199
21.1Features ..............................................................................................................199
21.2Overview .............................................................................................................199
21.3Clock generation .................................................................................................199
21.4SPI data modes and timing .................................................................................200
21.5Frame formats .....................................................................................................201
21.6Data transfer ........................................................................................................203
21.7AVR USART MSPIM vs. AVR SPI ......................................................................205
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