Datasheet

iv
2545F–AVR–06/05
18.9 USART Register Description ..............................................................................187
18.10 Examples of Baud Rate Setting .......................................................................191
19 USART in SPI Mode ............................................................................. 196
19.1 Overview ............................................................................................................196
19.2 Clock Generation ................................................................................................196
19.3 SPI Data Modes and Timing ..............................................................................197
19.4 Frame Formats ...................................................................................................198
19.5 Data Transfer .....................................................................................................199
19.6 USART MSPIM Register Description .................................................................201
19.7 AVR USART MSPIM vs. AVR SPI .....................................................................204
20 2-wire Serial Interface .......................................................................... 205
20.1 Features .............................................................................................................205
20.2 2-wire Serial Interface Bus Definition .................................................................205
20.3 Data Transfer and Frame Format .......................................................................206
20.4 Multi-master Bus Systems, Arbitration and Synchronization ..............................209
20.5 Overview of the TWI Module ..............................................................................211
20.6 TWI Register Description ...................................................................................213
20.7 Using the TWI .....................................................................................................217
20.8 Transmission Modes ..........................................................................................221
20.9 Multi-master Systems and Arbitration .................................................................234
21 Analog Comparator ............................................................................. 235
21.1 Analog Comparator Multiplexed Input ................................................................237
22 Analog-to-Digital Converter ................................................................ 239
22.1 Features .............................................................................................................239
22.2 Starting a Conversion .........................................................................................241
22.3 Prescaling and Conversion Timing .....................................................................242
22.4 Changing Channel or Reference Selection ........................................................244
22.5 ADC Noise Canceler ..........................................................................................245
22.6 ADC Conversion Result .....................................................................................250
23 debugWIRE On-chip Debug System .................................................. 255
23.1 Features .............................................................................................................255
23.2 Overview ............................................................................................................255
23.3 Physical Interface ...............................................................................................255
23.4 Software Break Points ........................................................................................256