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What are the Connection Modes for InTouch and KEPServerEX (Interactive, Service/SuiteLink, and DDE/FastDDE)?


Last Update: 11/7/2018

All types of DDE rely on the Windows Messaging Layer, which is essentially the Windows clipboard. Since this layer is not available to applications running as System Services, KEPServerEX must be configured to run in Interactive Mode in order to provide data to DDE clients. Users should note the following:

  • KEPServerEX V5 will install as a Service by default. To change the selected mode, open the Administration menu and then click Settings | Runtime Process.
  • KEPServerEX V4 does not install as a Service by default. To verify the process mode, open the server and then click Tools | Options.
  • Neither Vista nor Windows 7 support NetDDE.
  • For DDE format examples, refer to the information below and the "How Do I...?" topic in the product manual.

Making SuiteLink Connections from Wonderware
To make SuiteLink connections from Wonderware clients like InTouch to KEPServerEX, reference the name of the server's .exe file in the Application Name field.

  • For KEPServerEX V5, enter "server_runtime".
  • For KEPServerEX V4, enter "servermain".
  • For DDE and FastDDE connections, enter "kepdde".

Using DDE with the Server
Example 1: Accessing a Register Locally Using the Default Topic

  • Syntax: <application>|<topic>!<item>
  • Example: kepdde|_ddedata!Modbus.PLC1.40001, where:
    • Application: DDE service name
    • Topic: _ddedata*
    • Item: Modbus.PLC1.40001

      *The default topic for all DDE data not using an Alias Map entry.

Example 2: Accessing a Register Locally Using an Alias Name as a Topic

  • Syntax: <application>|<topic>!<item>
  • Example: kepdde|ModPLC1!40001, where:
    • Application: DDE service name
    • Topic: ModPLC1*
    • Item: 40001

      *The topic now using an Alias Map entry.
Related Products
DDE Client, KEPServerEX