Datasheet

iv
8023F–AVR–07/09
ATmega325P/3250P
16.9Asynchronous Operation of Timer/Counter2 .......................................................147
16.10Register Description ..........................................................................................149
17 SPI – Serial Peripheral Interface ......................................................... 154
17.1Features ..............................................................................................................154
17.2Overview .............................................................................................................154
17.3SS
Pin Functionality ............................................................................................159
17.4Data Modes .........................................................................................................159
17.5Register Description ............................................................................................160
18 USART0 ................................................................................................. 163
18.1Features ..............................................................................................................163
18.2Overview .............................................................................................................163
18.3Clock Generation .................................................................................................165
18.4Frame Formats ....................................................................................................168
18.5USART Initialization ............................................................................................169
18.6Data Transmission – The USART Transmitter ....................................................171
18.7Data Reception – The USART Receiver .............................................................173
18.8Asynchronous Data Reception ............................................................................177
18.9Multi-processor Communication Mode ................................................................180
18.10Register Description ..........................................................................................182
18.11Examples of Baud Rate Setting ........................................................................186
19 USI – Universal Serial Interface .......................................................... 191
19.1Features ..............................................................................................................191
19.2Overview .............................................................................................................191
19.3Functional Descriptions .......................................................................................192
19.4Alternative USI Usage .........................................................................................198
19.5Register Descriptions ..........................................................................................199
20 Analog Comparator ............................................................................. 203
20.1Overview .............................................................................................................203
20.2Analog Comparator Multiplexed Input .................................................................203
20.3Register Description ............................................................................................204
21 Analog to Digital Converter ................................................................ 206
21.1Features ..............................................................................................................206
21.2Overview .............................................................................................................206
21.3Operation .............................................................................................................207