How It Works

How the OPC A&E Server Toolkit Works

The OPC A&E Server Toolkit is a DLL (dynamic-link library) that you link with your application. Your application may be a new or existing application to which you want to add OPC A&E compliant interfaces, or an existing OPC Data Access Server.

The toolkit can be used with a variety of applications including: MFC, ATL, Win32, console, Windows service, and Windows CE.

The DLL exposes a simple set of objects and API calls behind which are aggregated all the COM interfaces and OPC object resources required to manage OPC A&E client connections.

What the Developer Does

As the developer, you work with the toolkit objects and API calls to provide the following.

	Define the event categories, vendor-specific attributes, and condition and sub-condition names using the toolkit's Configuration Database objects.
	For non-simple servers, populate a cache of event source objects (used for triggering event conditions) using the toolkit's Source Cache objects. Objects can be added and removed dynamically during the lifetime of the server.
	Notify the toolkit of simple and/or tracking events as your software detects them.
	Activate and deactivate event source conditions.
	When prompted by the toolkit, provide current values for vendor-specific event attributes.

What the Toolkit Does For Your Application

Here is a summary list of what the toolkit does for your application.

	Manages all OPC A&E client connections for your server.
	Efficiently creates, manages, and destroys OPC A&E COM objects as required.
	Using information in the Source Cache, automatically fulfills client browsing requests. You do not need to implement browsing.
	Manages event subscriptions and the related filtering and state management.
	Generate event notifications for connected OPC clients.
	Handle incoming event acknowledgements. Valid acknowledgements are passed through to your application for further processing.
	Manages the state of all conditions as per the state machine defined in the OPC A&E Standard.
	Service all query and administration requests.

More Details

Download the demonstration software for the OPC A&E Server Toolkit. The demo contains the complete server toolkit, including a Reference Manual, a sample implementation (with source code), and a guide to explain the sample implementation. You can even write your own server. Click here for the demo.