YOKOGAWA IR202, User Manual

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<CONTENTS>
IM 11G02Q02-51EN 2nd Edition : Sep. 04, 2020-00
Model IR202
Infrared Gas Analyzer
Communication Functions (MODBUS)
CONTENTS
IM 11G02Q02-51EN 2nd Edition
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PREFACE ........................................................................................................ i
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Safety Precautions ....................................................................................... ii
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After-Sales Warranty ................................................................................... iv
1. GENERAL .................................................................................................. 1-1
2. CONNECTION ........................................................................................... 2-1
3. MODBUS PROTOCOL .............................................................................. 3-1
3.1 Composition of message ................................................................................. 3-1
3.2 Response of slave station ................................................................................ 3-2
3.3 Function code .................................................................................................... 3-3
3.4 Calculation of error check code (CRC-16) .....................................................3-4
3.5 Transmission control procedure .....................................................................3-6
4. DETAILS OF MESSAGE ........................................................................... 4-1
4.1 Read-out word data (Function code : 03
H
) .....................................................4-1
4.2 Read-out word data (Read-out only) (Function code : 04
H
) ..........................4-2
4.3 Write-in word data (1 word) (Function code : 06
H
) ....................................................... 4-4
4.4 Write-in continuous word data
(Function code : 10
H
) ........................................................................................4-5
5. ADDRESS MAP AND DATA FORMAT ..................................................... 5-1
5.1 Data format ........................................................................................................ 5-1
5.1.1 Handling of decimal point position and measurement unit ................5-1
5.1.2 Handling at measurement data over-range .......................................5-2
5.2 Address map ..................................................................................................... 5-3
5.3 Supplement to address map ..........................................................................5-16
6. TROUBLE SHOOTING ............................................................................. 6-1
Revision Information ............................................................................................... i