Brainchild VR06 - DDE with Third-Party Applications (PLC, SCADA)

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DDE with third party applications
Once the data is available at Excel at particular cell, then data can be exchanged with the third party
applications like PLC, SCADA, and Visual Basic etc.
If data is to be exchanged with PLC, then PLC programmer can write Visual basic macro in Excel from
the following link
Excel – Tools – macro
For the source code examples, PLC programmer may check the PLC manuals for DDE sample macros.
It is also possible to exchange data from recorder to SCADA applications through DDE.
Example 1
DDE link between Allen-Bradley SLC 5/03 PLC and Excel
Task: Write a block of data (10 floating points) from Excel to PLC.
Name of the Excel file = Reports.XLS
Data Source: D 37 to D 46, data in total 10 cells
Target= PLC, Starting address= F8
User RSLinx to configure PLC and DDE link
DDE topic name in RSLinx= DDE_REPORTS
Sub Block_Write()
'open dde link: testsol=DDE Topic This is comment only
RSIchan = DDEInitiate("RSLinx", "DDE_REPORTS")
'write data thru channel This is comment only
DDEPoke RSIchan, "F8:2,L10", Range("[Reports.XLS]PROCESS!D37:D46")
'close dde link This is comment only
DDETerminate (RSIchan)
End Sub