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Modbus Service

Modbus serverimplementTag pointModbusregister , allowssupports Modbus Client host computerthrough Modbus TCPor Modbus RTU protocolread/write Tag point. supportsslave ID, canaddmultipleservice.
  • gatewaycommunication: Tag pointwhen, Modbusregisterpoint value .
gatewaycommunicationunder: Default value: Modbus Address point valuetablein"Default value"column value aftervalue: Modbus Address point valueafter value
  • servicestarttime: Modbus servicewhensecondsstart.

Modbus TCPConfiguration​

Modbus TCPservice, allowshost computerthrough Modbus TCPprotocolEthernet portconnectiongateway.
  • slave ID: gateway Modbus service slave ID; canthrough Add Slave IDaddmultipleslave ID
  • Port number: Settings Modbus TCPPort number, Default valueis 503.

select Enable Modbus TCP Service, click Save.

Figure 1 ModbusTCPserviceConfiguration

Modbus RTUConfiguration​

Modbus RTUservice, Click"Configuration"button, in openinaddspecifiedserial port, provide Modbus RTUservice. allowshost computerthrough Modbus RTUprotocolserial portconnection(RS-232/485)gateway.

Figure 2 Modbus RTUservice canthrough Add RTUaddserial port RTUservice.

Figure 3 createModbusRTUservice

Figure 4 ModbusRTUserviceConfiguration

Modbus DTUmodeConfiguration​

Modbus DTUmode, gatewayonwhen, throughfill in server Addressand Portconnectionserver, serverthroughgateway, gatewayIP. serverin the TCPlinkonthroughmodbus TCPormodbus RTUmessageread/writegateway Tag point.

Figure 5 ModbusDTUmodeConfiguration

message: specifiedmodbus TCPormodbus RTU messageperform.

interval: selectgatewayintervalupload, selectgatewayin onwhensend.

Modbus address mapping​

Tag pointModbusregisteron, Configurationstepsas follows:
  1. Click the Add button.
  2. in openwindowinselectneed to point;
  3. select the Modbus data area, data type, and byte order;
  4. Click the "OK" buttoncompletepoint add.
oncanaddmore pointAddresslist.

Figure 36 add Modbus service Address

Figure 37 Modbus servicepoint Double-click Tag pointcanmodifyModbusregister , can Configuration:
  • data area: 0 X (Coil Status),1 X (Input Status),3 X (Input Registers),4 X (Holding Register)data area.
  • Modbusregister Address: specifiedthe Tag pointin Modbus Address Address, Addressis 1. Modbusregister Address anddata area, such asdata areaselect 4 X (Holding Register), Modbusregister Addressfill in 1, the point Modbus Addressis 400001.
  • Modbusdata type: bool, bit, uint 16, int 16, uint 32, int 32, float, double, uint 64, int 6410 .
  • byte order: Null, Big-endian, Little-endian, Big-endian byte swap, Little-endian byte swap5.
  • Null: used tobool, bit, uint 16, int 16data type, byte order;
  • Big-Endian: mode, is (isvalue after)savein within Addressin, , savein within Addressin, storage modepointconvert/writestring: Addressto, from; in 4 3 2 1
  • Little-Endian: mode, is savein within Addressin, savein within Addressin, storage modeAddress anddata bits, Addressminutevalue, Addressminutevalue, and logic. in 1 2 3 4
  • Big-Endian byte swap: , in 2 1 4 3
  • Little-Endian byte swap: , in 3 4 1 2
  • Default value: is 9999, canmodify, in "gatewaycommunication"inselect"Default value", Tag pointwhen, Modbusregister point valuethe Default value.

Tool Softwaretestgateway MODBUSservice​

Modbus pollread Modbus TCPservice Example, stepsas follows:
  1. Modbus TCPservice, Addressas follows:

Figure 38 Modbus servicepoint
  1. the projectthroughtoolin "downloadproject"buttondownloadgatewayin.
  2. open Modbus Poll, Clickabovetoolin"Connection"under "Connect.", in openinselect"Modbus TCP/IP",input LM Gateway IP addressand Port number, Click"OK"completeconnection Configuration.

Figure 39 Modbus pollconnectiongatewayservice
  1. according to GCin Modbus servicepage Address, data typeandbyte ordermodify Modbus Polltoolin"Display", viewregister.

Figure 40 Configurationdata typeandbyte order

Figure 41 gateway Modbus service