ATmega1284P datasheet(376/380 Pages) ATMEL

376 / 380 page

8059D–AVR–11/09

ATmega1284P

16.4Data Modes .........................................................................................................166

16.5Register Description ............................................................................................168

USART ................................................................................................... 171

17.1Features ..............................................................................................................171

17.2USART1 and USART0 ........................................................................................171

17.3Overview .............................................................................................................171

17.4Clock Generation .................................................................................................172

17.5Frame Formats ....................................................................................................175

17.6USART Initialization ............................................................................................176

17.7Data Transmission – The USART Transmitter ....................................................177

17.8Data Reception – The USART Receiver .............................................................180

17.9Asynchronous Data Reception ............................................................................184

17.10Multi-processor Communication Mode ..............................................................187

17.11Register Description ..........................................................................................189

17.12Examples of Baud Rate Setting ........................................................................194

USART in SPI Mode ............................................................................. 198

18.1Features ..............................................................................................................198

18.2Overview .............................................................................................................198

18.3Clock Generation .................................................................................................198

18.4SPI Data Modes and Timing ...............................................................................199

18.5Frame Formats ....................................................................................................199

18.6Data Transfer ......................................................................................................201

18.7AVR USART MSPIM vs. AVR SPI ......................................................................203

18.8Register Description ............................................................................................204

2-wire Serial Interface .......................................................................... 207

19.1Features ..............................................................................................................207

19.22-wire Serial Interface Bus Definition ..................................................................207

19.3Data Transfer and Frame Format ........................................................................208

19.4Multi-master Bus Systems, Arbitration and Synchronization ...............................211

19.5Overview of the TWI Module ...............................................................................213

19.6Using the TWI ......................................................................................................215

19.7Transmission Modes ...........................................................................................218

19.8Multi-master Systems and Arbitration ..................................................................231

19.9Register Description ............................................................................................232

AC - Analog Comparator ..................................................................... 237

ATmega1284P Datasheet(PDF) 376 Page - ATMEL Corporation