1. Intellut on Copyright 1998 Intellution, Inc. All Rights Reserved Notes to Presenter These slides are scripted (they have notes pages) Some of these slides can be (or may already be) ‘hidden’ in order to produce ‘short’ versions of this talk. Note - It would be nice to add a ConnectionPoint overview to the ‘detailed’ version. - See the Alarms and Events ppt which has one. The ‘fixed’ template has been applied to this file (11/4/98)

2. Intellut on Copyright 1998 Intellution, Inc. All Rights Reserved TM OLE for Process Control and Factory Automation Al Chisholm - OPC Technical Chairman 10/98 OPC Data Access 2.0 Technical Overview

3. Intellut on Copyright 1998 Intellution, Inc. All Rights Reserved Topics A review of the Data Access Problem Design Features Assumptions about the Applications The Objects The functionality they provide

4. Intellut on Copyright 1998 Intellution, Inc. All Rights Reserved Why is OPC Data Access needed? Software Driver Software Driver Software Driver Software Driver Display Application Trend Application Report Application

5. Intellut on Copyright 1998 Intellution, Inc. All Rights Reserved How does OPC Solve the Problem? Software Driver Software Driver Software Driver Software Driver OPC Display Application Trend Application Report Application OPC

6. Intellut on Copyright 1998 Intellution, Inc. All Rights Reserved Where does OPC Data Access Fit? Low level sensors Typically use a dedicated Hardware Interface and protocol Device Specific I/O Control Data Monitor SubSystem OPC OPC (via DCOM)can also be used between subsystems and Management Consoles OPC is generally used between Monitoring applications and I/O specific software drivers

7. Intellut on Copyright 1998 Intellution, Inc. All Rights Reserved What data does OPC provide? Real time sensor data - temp, pressure, flow Control parameters - open, close, run, stop Status information – Status of the hardware connection – Status of the local software and subsystem OPC can expose any data available OPC Interfaces Sensor Data Comm Status System Performance OS Statistics

8. Intellut on Copyright 1998 Intellution, Inc. All Rights Reserved Features of OPC Data Access Based on COM - to leverage Microsoft ‘Plumbing’ Flexible - to support many applications Efficient & Scalable - to support large applications Hi performance - well behaved on a Network Easy to understand Widely accepted

9. Intellut on Copyright 1998 Intellution, Inc. All Rights Reserved Problems not solved by OPC Data Access Global Naming Alarms and Events (Separate OPC Spec) Security (DCOM and/or Separate OPC Spec) Structured Data (supported but not specified)

10. Intellut on Copyright 1998 Intellution, Inc. All Rights Reserved Assumptions About the Architecture Each OPC Server such as Data Access is a Separate Object The Data Access Server provides a window into Existing Data; it is not a configuration system. Data is accessed by Name (a string) which will generally be vendor or hardware specific. Data for lists of items can be read explicitly (polled) or subscriptions can be created. Existing SCADA, DCS, PLC or other Data Source FIC101, FIC102... OPC Server OPC Client

11. Intellut on Copyright 1998 Intellution, Inc. All Rights Reserved Assumptions about the Applications Applications are interested in a subset of the Data Items (Tags) available within the underlying Control sub-system. Applications are interested in many different subsets of Data Items at different times and may have variable requirements for response and resolution. Applications want to be independent of the data structures (or objects) used by the sub-systems. (I.e. they want symbolic access to the data).

12. Intellut on Copyright 1998 Intellution, Inc. All Rights Reserved The Logical Object Model OPCServer OPCGroup OPC/COM Interfaces OPCGroup OPCGroup(s) OPCItem(s)

13. Intellut on Copyright 1998 Intellution, Inc. All Rights Reserved Typical Server Design OPC/COM Interfaces OPC Group & Item Management Item Data Optimization and Monitoring Device Specific Protocol Logic Hardware Connection Management

14. Intellut on Copyright 1998 Intellution, Inc. All Rights Reserved The Logical Object Model The Group OPC Group XYZ OPC Item

15. Intellut on Copyright 1998 Intellution, Inc. All Rights Reserved The Logical Object Model The Item The ITEM is separate OPC specific object independent of the underlying system. OPC ServerThe ‘Real’ data sub-system (e.g. SCADA or DCS System) FIC101 TIC101 FIC102 TIC102 FIC103 TIC103 FIC104 FIC105... OPC Groups... OPC Item

16. Intellut on Copyright 1998 Intellution, Inc. All Rights Reserved The Server Interfaces The server is a COM object which provides: IOPCServer IOPCBrowseServerAddressSpace (optional) IOPCCommon (2.0) IOPCItemProperties(2.0) IConnectionPointContainer(2.0) OPCServer

17. Intellut on Copyright 1998 Intellution, Inc. All Rights Reserved The Group Interfaces The Group is a COM object which provides: IOPCGroupStateMgt IOPCAsyncIO2 (2.0 - replaces IOPCAsyncIO) IOPCItemMgt IOPCSyncIO IConnectionPointContainer (2.0 replaces IDataObject) OPCGroup

18. Intellut on Copyright 1998 Intellution, Inc. All Rights Reserved The OPC Server Object, Its Interfaces and Methods OPCServer

19. Intellut on Copyright 1998 Intellution, Inc. All Rights Reserved The Server Interface Methods: IOPCServer AddGroup RemoveGroup GetGroupByName CreateGroupEnumerator GetErrorString GetStatus

20. Intellut on Copyright 1998 Intellution, Inc. All Rights Reserved The Server Interface Methods: IOPCBrowseServerAddressSpace QueryOrganization ChangeBrowsePosition BrowseOPCItemIDs GetItemID

21. Intellut on Copyright 1998 Intellution, Inc. All Rights Reserved The Server Interface Methods: IOPCCommon Get/SetLocaleID QueryAvailableLocaleIDs GetErrorString SetClientName

22. Intellut on Copyright 1998 Intellution, Inc. All Rights Reserved The Server Interface Methods: IOPCItemProperties QueryAvailableProperties GetItemProperties LookupItemProperties

23. Intellut on Copyright 1998 Intellution, Inc. All Rights Reserved The Server Interface Methods: IConnectionPointContainer EnumConnectionPoints FindConnectionPoint Supports the IOPCShutdown Callback into the Client

24. Intellut on Copyright 1998 Intellution, Inc. All Rights Reserved The OPC Group Object, its Interfaces and Methods OPCGroup

25. Intellut on Copyright 1998 Intellution, Inc. All Rights Reserved The Group Interface Methods: IOPCGroupStateMgt GetState SetState SetName CloneGroup

26. Intellut on Copyright 1998 Intellution, Inc. All Rights Reserved The Group Interface Methods: IOPCItemMgt AddItems ValidateItems RemoveItems SetActiveState SetClientHandles SetDatatypes CreateEnumerator

27. Intellut on Copyright 1998 Intellution, Inc. All Rights Reserved The Group Interface Methods: IOPCAsyncIO2 Read Write Refresh2 Cancel2 SetEnable GetEnable

28. Intellut on Copyright 1998 Intellution, Inc. All Rights Reserved The Group Interface Methods: IOPCSyncIO Read Write

29. Intellut on Copyright 1998 Intellution, Inc. All Rights Reserved The Group Interface Methods: IConnectionPointContainer (Replaces IDataObject) EnumConnectionPoints FindConnectionPoint Supports the IOPCDataCallback callback into the Client

30. Intellut on Copyright 1998 Intellution, Inc. All Rights Reserved The Group Interface Methods: IConnectionPoint Advise Unadvise

31. Intellut on Copyright 1998 Intellution, Inc. All Rights Reserved The Client Side Intefaces The Client provides 2 COM interfaces that the server can call IOPCShutdown IOPCDataCallback Server Object Group Object(s) Client IOPCDataChange IOPCShutdown

32. Intellut on Copyright 1998 Intellution, Inc. All Rights Reserved The Client Side Interfaces: IOPCShutdown (This is a callback from the Server into the Client) ShutdownRequest

33. Intellut on Copyright 1998 Intellution, Inc. All Rights Reserved The Client Side Interface: IOPCDataCallback (This is a callback from the GROUP into the Client. It replaces IAdviseSink) OnReadComplete OnWriteComplete OnCancelComplete OnDataChange

34. Intellut on Copyright 1998 Intellution, Inc. All Rights Reserved Performance and Flexibility OPC Data Access is complete, powerful and flexible because it is a combination of the best ideas of many of the best companies in our business. OPC Data Access is Fast because it was designed from the start with networking in mind.

35. Intellut on Copyright 1998 Intellution, Inc. All Rights Reserved Summary The OPC Data Access 2.0 Interfaces Allow applications to easily access subsystem data Support polled or exception based access Are optimized for use over a network Are designed to be vendor neutral Are exceptionally flexible and efficient www.opcfoundation.org