The OPC Diagnostics Window provides a real-time and historical view of OPC events that occur between any OPC client and the TOP Server. An event is a method call that a client makes to the TOP Server, or a callback the TOP Server makes to a client. You must be in Runtime Mode in the Configuration to be able to access the diagnostics.  See Offline Editing for more information.

The OPC Diagnostics Window is separate from the main TOP Server configuration window, which allows you to hide the window even while diagnostics are being captured. In the event that there is an issue between a client and the TOP Server, the Diagnostics Window can be opened to display the events that have occurred. The operation of the OPC Diagnostics Window can be controlled through its’ menu, toolbar or by right-clicking in the Event Window.

The events and details captured by this utility are specific to the OPC Data Access 1.0, 2.0 and 3.0 Custom Specifications. To determine the meaning of the data presented by this window, refer to those specifications. Copies of these specifications are available to OPC Foundation members on the OPC Foundation web site (Information on joining the OPC Foundation is also provided). 

See the TOP Server Help file under “Built in Diagnostic, OPC Diagnostics” for information on how to use this feature including settings and filters.