I have a situation where I have a VB app that differentiates between left hand parts and right hand parts. When I bring up the Form for left hand, it goes out and defines an OPCServer and connects to it. Then has the topic it connects to, and has about 40 items it writes to the PLC.

Then I have a form for the right hand and it does the same thing. Both forms come up, but whichever form that is accessed first is the only form which will work. My question is, do I need to define seperate OPCservers for the application, or just one? Plus, we want to be able to have more than one application running, talking to the same OPC server. But the topic can only be accessed from one app or the other, not both.

Any ideas?

thanks.

 

You can try opcware http://www.opcware.com/OPCWare.html

This is activex controls and you can put them on your Visual Basic forms, each activex control works independent of the other. You can connect to as many opc servers as you like, all at the same time. It will save you buckets of time and head scratching/headaches - believe me I've been down that road too.