OPC client

Hi.

I have an OPC server, and i was looking for a VB (not .NET) code to create an OPC client to read tags, but I only find comercial programs, who has an example (OPC client) in visual Basic .

Thanks.

Hi,


Beijer Electronics have a (very) basic sample OPC-client (VB6) that you can download from the following link:
http://www.beijerelectronics.com/web/BExFilePileHMI.nsf/0/99B3A48A251CAE98C12573750055D364/$FILE/VBOPCClientSample.zip

//Supporter

The OPC foundation has sample (reference) VB6 OPC client code on their site. I believe you have to be a member to download it, though.

Software Toolbox web site has an OPC client package as well as HMI objects that can be hooked directly into the OPC client. In other words you can construct an HMI in VB with minimal coding and you can have unlimited run time distribution. I wrote an OPC client long time ago when OPC specs were still free on ODVA web site. Now you have to pay. I found out recently that the same code that used to run well on Widows 2000 had some issues on Windows XP, I had to tweak the code and that required painfull re-learning of the OPC. I tell you it's not worth the effort to write an OPC client for someone who does system integration.

Also a word of caution. The Beijer example is great but it uses their wrapper, you will need to have a wrapper specific to your application. For example AB has their own wrapper that comes on RSLinx CD.

Check out Kepware's Sample code that isntalls with it server. there are also some very basic examples in the knowledge base.

http://www.kepware.com/KEP_KB/default.asp?ToDo=view&questId=84&catId=60