1. Generic OPC UA Server Framework
Piotr Nikiel
For OPC UA Developers
3rd Mar 2015

2. Intro What is this? Where does rapidity come from?
A framework for rapid creation of OPC UA servers, using C++.
Where does rapidity come from?
Automatic generation of majority of source code
Establishing common architecture and convention
What does it base on?
The OPC UA Toolkit
A number of open source libraries and tools

3. Organization of Readout
Configurator
OPC UA Address space
Device Logic
WinCC OA OPC UA Client
Other OPC UA Client #1
Other OPC UA Client #2
Hardware access layer
Hardware
XML config file
configures
OPC UA Server
TCP/IP

4. Modus Operandi START Get&Understand model of target device/system
Create(edit) design file
Generate OPC UA Address Space and Configuration module
(Re)generate device logic stubs
(Re)implement device logic
Build
Test, evaluate …
Device model is OK Y N N
Device logic is OK
Work to be done =
design file + device logic + testing
Roughly 50-90% lines of code generated Y
END

5. Elements of the Design File
Very much alike traditional Object Oriented design
Main elements
Classes
E.g. System, Crate, Channel, PowerSupply, Probe, Fan, …
Relations between classes
E.g. System has Crates, Crate has Channels and Fans, Channel has Probes
Variables which belong to classes
E.g. voltage, current, temperature, fan speed, on/off, …
Various types: cache and source variable, for in-memory data as well as asynchronous and synchronous device access (and synchronization)
XML Schema available
Using Eclipse helps a lot in editing (like filling up a form)

6. Configuration Module Generated parts:
XSD Schema for server’s configuration file
Configuration loader
builds address space & device hierarchy accordingly
Configuration validator
C++ mappings
Access configuration data from device logic without writing any XML handling code

7. Example – Simple 2 Class Design
TEXTUAL CONTENT
VISUALIZATION
DESIGN FILE
CONFIGURATION FILE
(generated diagram)
<class name=“PowerSupplyChannel”>
<cachevariable name=“current” dataType=“Float”/>
</class>
<class name=“PowerSupply”>
<sourcevariable name=“state” dataType=“Int”/>
<hasobjects class=“PowerSupplyChannel”/>
In OPC UA client (from UA Toolkit):
<PowerSupply name=“powerSupply1”>
<PowerSupplyChannel name=“channel1”/>
<PowerSupplyChannel name=“channel2”/>
</PowerSupply>

8. Demo 1
Editing in Eclipse
Design file
Config file

9. Build System & Tools Build system Tools Provided out-of-the-box
Tightly integrated with the workflow
Based around CMake
Tools
Consistency checker
Visualization tools
Design file validator and upgrade tool
A tool for upgrading your project to newer framework version
„Honky tonk” generator – quick way of testing your address space
Easy RPM Generator
Doxygen integrated by default

10. Demo 2
Building a project

11. For More Advanced Designs…

12. WinCC OA Integration Features: Generation of Data Point Types
basing on classes declared in design file
(arriving soon) Creation of Data Points
Basing on config file
Generation of CTRL code for peripheral OPC UA address setup

13. WinCC OA Integration - Screenshot

14. Advantages Programming reduced to device logic implementation
No knowledge of OPC UA Toolkit required
Coherency (single point of input: Design file, everything else generated from that)
Profit from achievements of other OPC UA developments
e.g. calculated items (based on CANopen server)
Quick integration of custom components into SCADA

15. Current State Generic OPC UA Server framework: production-ready 0.96
Validated with SLC6.6 production systems
Windows version is in progress
OPC UA Servers using this approach:
In production:
ATLAS Wiener server for VME crates (custom protocol over CAN)
ATLAS LAr Purity server (custom protocol over CAN)
S7 TSPP PLC OPC UA Server (Siemens native protocol over TCP/IP)
In development:
EN-ICE Caen HV server (Caen protocol over TCP/IP)
ATLAS IBL FEI4 server (custom protocol over TCP/IP)
ATLAS TileCal HV Micro server (custom protocol over CAN)
Test servers:
Simple CANopen server (CANopen over CAN)

16. Deliverables
The frameworks comes as a complete package ready to create new OPC UA server projects
SVN Link:
Documentation:
Video tutorials on youtube
Written documentation
Have a look inside Documentation on SVN link above

17. BACKUP SLIDES

18. Software Dependencies
Mandatory:
Suitable C++ compiler (gcc is assumed by default)
The Unified Automation OPC UA Toolkit, version 1.3.3Boost development libraries. (In principle, boost-regex, boost-devel and boost-program-options should be sufficient)
XSLT processor capable of XSLT2.0 processing. We use Saxon9 which is bundled with the package.
Java run time environment, to run the Saxon XSLT Processor.
Cmake version 2.8 or later. Available in SLC6 as cmake28 package.
Recommended:
Schema-aware XML editor. We use Eclipse, as can be seen in the screencasts.
Good C++ IDE / editor. We use Eclipse, as can be seen in the screencasts.
Good merge tool. We use kdiff3 (available as kdiff3 RPM in SLC6 Linux).
ArtisticStyle – for formatting of automatically generated code
Graphviz for UML visualization
UnifiedAutomation UaExpert or any other OPC UA Client for exploring OPC UA address space.
Valgrind, for checking memory-related problems. (valgrind RPM in SLC6)
PDF viewer for opening UML-like diagrams created from design file.
Doxygen for generating documentation.
RPM Build tools for RPM generation

19. Transformations Diagram

20. What is generated from the design file? Backup
Complete address space
Complete configuration
Configuration file loader (aka “Configurator”) with config validator
Schema for configuration file
Device logic stubs
Ready for providing implementation
WinCC OA integration
Generation of DPTs from classes description
Generation of OPC UA Address Setup
Autogenerated tools, diagrams, etc …