Yokogawa EJX930A - Manual (Page 3)

ii
IM 01C25R05-01EN
4. Diagnostics ............................................................................................... 4-1
4.1 Self-Diagnostics ................................................................................................4-1
4.1.1
Identify Problems by Using the Configuration Tool ............................4-1
4.1.2 Checking with Integral Indicator .........................................................4-1
4.1.3 Status Information .............................................................................4-1
4.2 Alarms and Countermeasures ........................................................................4-2
5. Modbus Communication ......................................................................... 5-1
5.1 General ...............................................................................................................5-1
5.2 Message construction ......................................................................................5-1
5.3 Broadcast ...........................................................................................................5-1
5.4 Function code ....................................................................................................5-1
5.4.1
01 (0x01) Read Coils .........................................................................5-1
5.4.2 02 (0x02) Read Discrete Inputs .........................................................5-2
5.4.3 03 (0x03) Read Holding Registers.....................................................5-2
5.4.4 04 (0x04) Read Input Registers .........................................................5-2
5.4.5 05 (0x05) Write Single Coil ................................................................5-2
5.4.6 08 (0x08) Diagnostics ........................................................................5-3
5.4.7 16 (0x10) Write Multiple registers ......................................................5-3
5.5 Response error code ........................................................................................5-3
5.6 Data format ........................................................................................................5-4
5.7 Address Map ......................................................................................................5-4
5.7.1
Address Map (Basic Information) ......................................................5-5
5.7.2 Address Map (Detail Information) ......................................................5-6
5.7.3 Enumeration table list ......................................................................5-14
6. Modbus Communication Troubleshooting ........................................... 6-1
Revision Information ...............................................................................................i