Cause a macro to run when a OPC DataHub point changes value. Here is one macro that runs another macro every time a certain cell's value is updated by a DDE message. The macro that gets run is link_updated. It simply increments the value in cell A1. You can easily change this example to meet your needs. The set_link macro tells the workbook to run the link_updated macro whenever the DataHub sends a DDE message about point0001. You can also change the name of the DataHub point as needed.

Add to Sheet1 macro code:

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Sub link_updated()
    Cells(1, 1) = Cells(1, 1) + 1
End Sub
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Run once to establish the link:

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Sub set_link()
    ThisWorkbook.SetLinkOnData "datahub|default!'point0001'", "Sheet1.link_updated"
End Sub
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