This article has been inspired by an e-mail conversation we have recently had with a customer. He had written a piece of code "from the scratch" that connected to his OPC Data Access server, and was able to obtain the data he needed to store in a database. He therefore had doubts about the value and usefulness of a library such as QuickOPC; it appeared to him that the task of writing an OPC client is quite easy.

During the course of a discussion, we have identified quite a lot of points that his code was lacking. Here are some questions we have asked:

This article describes best practices that aid in developing applications and libraries that use the QuickOPC library.

All information described in this article is merely a set of guidelines to aid development. These guidelines do not constitute an absolute truth. They are patterns that we found helpful; not rules that should be followed blindly. There are situations where certain guidelines do not apply. It is up to each individual developer to decide if a certain guideline makes sense in each specific situation.

The guidelines in this article are listed in no particular order.

Our products are listed on the new OPC Foundation Web site.

• QuickOPC Client Toolkit
• StreamInsight Option for QuickOPC
• PiiGAB M-Bus OPC Server - this is listed because we have helped developed the server and provided the OPC interoperability and compliance testing for it.
• OPC Development Services

Our products are listed on OPC Foundation Web site.