OPC Data Control - Free OPC Server and Item Browser

Included with the OPC Data ActiveX at no additional charge is our Server and Item Browser - these functions give you an easy way to add OPC Server and Item Browsing to your Visual Basic application, functions that normally would take you dozens and possibly over 100 lines of code to implement with a "free wrapper" -- here it's all done, debugged, and ready to drop into your application.  To try this out for yourself, download our free 10 day trial software demo and install it - in the Program Files\OPC Data Control\Samples folder you will find the VB source for the program from which these screenshots were made.

Important Note! Updated Browse Demo (3/2004):
We have made some updates to the browse demo to improve how it works across DCOM connections - primarily we changed so that we always use the server CLSID that is returned from the server browser instead of the ProgID when calling to read items, write items, or browse for items. This is faster for one thing and also works better over DCOM. 

Download the updated VB Source and EXE here.

Also available in Borland Delphi format here.

If you plan to use this demo to connect between remote machines and need help in DCOM setup, we recommend you review our DCOM Tutorial that supplies recommended settings - if you are using this on a local machine, then you should not need to make any DCOM settings.

When you first run the OPC Browse Sample, you see the following screen: Click on browse to bring up our built in OPC Server Browser.

Server Browsing

Our Server Browser dialog is built and ready to go, and can be called with one line of code in your VB program. The dialog gives you the ability to browse your local machine for available OPC Data Access 1 and 2 servers, as well as remote machines via DCOM that you have security clearance for. 

Simply pick the OPC server you want to connect to and click OK. This custom dialog will return to your VB program either the ProgID or the GUID for the OPC server depending on the choice made by the user. You can then use that server identifier in your code to connect to the OPC server.

When running the demo program, after you click on OK in the Server Browser, click "Connect" on the main screen to connect to your chosen OPC server.

Item Browsing

Once you've connected to the OPC server, click the Browse button and our custom Item Browser Dialog is shown. This custom dialog can be called and displayed for your user with one line of code and it will return the necessary information to your program to read/write/subscribe to the tag chosen by the user.