Contents
1 Introduction 5
1.1 Preface ........................................................................................................ 5
1.2 Typographical conventions ....................................................................... 5
2 Protocol description 7
2.1 Master-Slave principle ............................................................................... 7
2.2 Transmission mode (RTU) ......................................................................... 7
2.3 Device address ........................................................................................... 8
2.4 Timing of the communication ................................................................... 8
2.5 Structure of the data blocks ................................................................... 11
2.6 Function codes ......................................................................................... 12
2.6.1 Read n words ............................................................................................. 12
2.6.2 Write one word ........................................................................................... 13
2.6.3 Write n words ............................................................................................. 14
2.7 Transmission format (integer, float and text values) ............................. 15
2.8 Checksum (CRC16) .................................................................................. 17
2.9 Error processing ...................................................................................... 18
3 RS485 interface 19
3.1 Connection diagram ................................................................................ 19
3.2 Configuration ............................................................................................ 20
4 Modbus addresses 21
4.1 Process data ............................................................................................ 21
4.2 Set point values ........................................................................................ 22
4.3 Controller parameters ............................................................................. 23
4.4 Configuration ............................................................................................ 23
4.5 Commands ............................................................................................... 24
4.6 RAM memory ............................................................................................ 25
To Next Page
Loading...
Need help?
General