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Chapter 2
Servers
After you configure and save the tags, complete the following steps to make
sure the server is providing data properly.
1.
Start the Tag Engine by selecting Tools»DSC Module»
Launch Engine.
2.
Open the Tag Monitor by selecting Tools»DSC Module»
Monitor Tags.
3.
Double-click tags under the server in the left tree.
4.
Make sure the data values and time stamps change.
If you cannot get live data with the Tag Monitor, use the configuration
utility for that server to check the installation and configuration. Check the
status of tag data in the Quality column of the Tag Monitor.
Accessing OPC Servers Using the DSC Module as an
OPC Client
The DSC Module can function as an OPC client and communicate with any
server implementing the OPC Foundation OPC server interface, which is a
Microsoft COM-based standard. The DSC Module finds all OPC servers
installed on the computer and reads any available information about the
server capabilities and items directly from the server.
Configuring the DSC Module OPC Client
You might need to configure the DSC Module OPC client for the following
reasons.
•
If the server does not support asynchronous communication, you can
force the client to use synchronous communication.
•
If the server has many OPC items, you can increase the maximum
number of items that display while you browse the server.
•
If you perform many writes to the server and receive an output queue
overflow, increase the length of the OPC write queue, which contains
requested but not completed asynchronous writes to the OPC server.
Complete the following steps to configure the DSC Module OPC client.
1.
Open the Server Browser by selecting Tools»DSC Module»
Advanced»Server Browser.
2.
Click the OPC Client Settings button.
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DSC Module Developer Manual