JUMO DICON 400, Interface Description, Page: 3 / 44

Contents
1 Introduction 5
1.1 Preface .......................................................................................................... 5
1.2 Typographical conventions ......................................................................... 6
1.2.1 Warning signs ................................................................................................. 6
1.2.2 Note signs ...................................................................................................... 6
1.2.3 Presentation ................................................................................................... 6
2 Protocol description 7
2.1 Master-slave principle ................................................................................. 7
2.2 Transfer mode (RTU) .................................................................................... 7
2.3 Instrument address ...................................................................................... 8
2.4 Timing of the communication ..................................................................... 8
2.4.1 Timing of a data request .............................................................................. 10
2.4.2 Communication during the internal processing time of the slave ................ 11
2.4.3 Communication during the response time of the slave ............................... 11
2.5 Structure of the data blocks ...................................................................... 11
2.6 Error handling ............................................................................................. 11
2.7 Checksum (CRC16) .................................................................................... 13
2.8 Interface ...................................................................................................... 14
3 Functions 15
3.1 Read n words .............................................................................................. 15
3.2 Write 1 word ................................................................................................ 16
3.3 Write n words .............................................................................................. 17