Figure2_

 

 

 

Figure4_

 

     OPC UA Specification

OPC 10000-19

 

OPC Unified Architecture

Part 19: Dictionary Reference

 

 

Release 1.04

2020-03-05

 

 

 

 

 

 


 

Figure1_

Specification Type:

Industry Standard Specification

Comments:

Report or view errata: http://www.opcfoundation.org/errata

 

 

 

 

Document
Number

OPC 10000-19

 

 

Title:

OPC Unified Architecture

Part 19 :Dictionary Reference

Date:

2020-03-05

 

 

 

 

Version:

Release 1.04

Software:

MS-Word

 

 

Source:

OPC 10000-19 - UA Specification Part 19 - Dictionary Reference 1.04.docx

 

 

 

 

Author:

OPC Foundation

Status:

Release

 

 

 

 


 

 

CONTENTS

Page

 

1      Scope. 1

2      Normative references. 1

3      Terms, definitions, abbreviated terms, and conventions. 1

3.1     Terms and definitions. 1

4      Dictionary Reference Information Model overview. 1

4.1     General 1

4.2     Overview. 2

5      OPC UA ObjectTypes. 3

5.1     DictionaryEntryType. 3

5.2     DictionaryFolderType. 3

5.3     IRDI ISO/IEC 11179-6 conformant DictionaryEntryType. 3

5.4     URI based dictionary entry type. 3

6      OPC UA ReferenceTypes. 3

6.1     HasDictionaryEntry ReferenceType. 3

7      OPC UA VariableTypes. 4

7.1     MultiStateDictionaryEntryDiscreteBaseType VariableType. 4

7.2     MultiStateDictionaryEntryDiscreteType VariableType. 4

8      OPC UA Objects. 5

8.1     Dictionaries Object 5

 


 

Figures

 

Figure 1 – The dictionary reference types................................................ 3

 


Tables

Table 1 – MultiStateDictionaryEntryDiscreteBaseType Definition. 4

Table 2 – MultiStateDictionaryEntryDiscreteType Definition. 4

 


 

OPC Foundation

____________

 

UNIFIED ARCHITECTURE

FOREWORD

This specification is the specification for developers of OPC UA applications. The specification is a result of an analysis and design process to develop a standard interface to facilitate the development of applications by multiple vendors that shall inter-operate seamlessly together.

Copyright © 2006-2020, OPC Foundation, Inc.

AGREEMENT OF USE

COPYRIGHT RESTRICTIONS

Any unauthorized use of this specification may violate copyright laws, trademark laws, and communications regulations and statutes. This document contains information which is protected by copyright. All Rights Reserved. No part of this work covered by copyright herein may be reproduced or used in any form or by any means--graphic, electronic, or mechanical, including photocopying, recording, taping, or information storage and retrieval systems--without permission of the copyright owner.

OPC Foundation members and non-members are prohibited from copying and redistributing this specification. All copies must be obtained on an individual basis, directly from the OPC Foundation Web site
HTUhttp://www.opcfoundation.orgUTH.

PATENTS

The attention of adopters is directed to the possibility that compliance with or adoption of OPC specifications may require use of an invention covered by patent rights. OPC shall not be responsible for identifying patents for which a license may be required by any OPC specification, or for conducting legal inquiries into the legal validity or scope of those patents that are brought to its attention. OPC specifications are prospective and advisory only. Prospective users are responsible for protecting themselves against liability for infringement of patents.

WARRANTY AND LIABILITY DISCLAIMERS

WHILE THIS PUBLICATION IS BELIEVED TO BE ACCURATE, IT IS PROVIDED "AS IS" AND MAY CONTAIN ERRORS OR MISPRINTS. THE OPC FOUDATION MAKES NO WARRANTY OF ANY KIND, EXPRESSED OR IMPLIED, WITH REGARD TO THIS PUBLICATION, INCLUDING BUT NOT LIMITED TO ANY WARRANTY OF TITLE OR OWNERSHIP, IMPLIED WARRANTY OF MERCHANTABILITY OR WARRANTY OF FITNESS FOR A PARTICULAR PURPOSE OR USE. IN NO EVENT SHALL THE OPC FOUNDATION BE LIABLE FOR ERRORS CONTAINED HEREIN OR FOR DIRECT, INDIRECT, INCIDENTAL, SPECIAL, CONSEQUENTIAL, RELIANCE OR COVER DAMAGES, INCLUDING LOSS OF PROFITS, REVENUE, DATA OR USE, INCURRED BY ANY USER OR ANY THIRD PARTY IN CONNECTION WITH THE FURNISHING, PERFORMANCE, OR USE OF THIS MATERIAL, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.

The entire risk as to the quality and performance of software developed using this specification is borne by you.

RESTRICTED RIGHTS LEGEND

This Specification is provided with Restricted Rights. Use, duplication or disclosure by the U.S. government is subject to restrictions as set forth in (a) this Agreement pursuant to DFARs 227.7202-3(a); (b) subparagraph (c)(1)(i) of the Rights in Technical Data and Computer Software clause at DFARs 252.227-7013; or (c) the Commercial Computer Software Restricted Rights clause at FAR 52.227-19 subdivision (c)(1) and (2), as applicable. Contractor / manufacturer are the OPC Foundation,. 16101 N. 82nd Street, Suite 3B, Scottsdale, AZ, 85260-1830

COMPLIANCE

The OPC Foundation shall at all times be the sole entity that may authorize developers, suppliers and sellers of hardware and software to use certification marks, trademarks or other special designations to indicate compliance with these materials. Products developed using this specification may claim compliance or conformance with this specification if and only if the software satisfactorily meets the certification requirements set by the OPC Foundation. Products that do not meet these requirements may claim only that the product was based on this specification and must not claim compliance or conformance with this specification.

Trademarks

Most computer and software brand names have trademarks or registered trademarks. The individual trademarks have not been listed here.

GENERAL PROVISIONS

Should any provision of this Agreement be held to be void, invalid, unenforceable or illegal by a court, the validity and enforceability of the other provisions shall not be affected thereby.

This Agreement shall be governed by and construed under the laws of the State of Minnesota, excluding its choice or law rules.

This Agreement embodies the entire understanding between the parties with respect to, and supersedes any prior understanding or agreement (oral or written) relating to, this specification.

ISSUE REPORTING

The OPC Foundation strives to maintain the highest quality standards for its published specifications; hence they undergo constant review and refinement. Readers are encouraged to report any issues and view any existing errata here: HTUhttp://www.opcfoundation.org/errataUTH

 


OPC Unified Architecture Specification

 

Part 19: Dictionary Reference

 

 

 

 

1             Scope

This specification defines an Information Model of the OPC Unified Architecture. The Information Model describes the basic infrastructure to reference from an OPC UA Information Model to external dictionaries like IEC Common Data Dictionary or eCl@ss.

2             Normative references

The following referenced documents are indispensable for the application of this specification. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments and errata) applies.

OPC 10000-1, OPC Unified Architecture - Part 1: Overview and Concepts

http://www.opcfoundation.org/UA/Part1/

OPC 10000-3, OPC Unified Architecture - Part 3: Address Space Model

http://www.opcfoundation.org/UA/Part3/

OPC 10000-4, OPC Unified Architecture - Part 4: Services

http://www.opcfoundation.org/UA/Part4/

OPC 10000-5, OPC Unified Architecture - Part 5: Information Model

http://www.opcfoundation.org/UA/Part5/

OPC 10000-8, OPC Unified Architecture - Part 8: Data Access

http://www.opcfoundation.org/UA/Part8/

OPC 10001-5, OPC Unified Architecture V1.04 - Amendment 5: Dictionary Reference

http://www.opcfoundation.org/UA/Amendment5/

3             Terms, definitions, abbreviated terms, and conventions

3.1       Terms and definitions

For the purposes of this document, the terms and definitions given in OPC 10000-1, OPC 10000-3, and OPC 10000-5 apply.

All used terms are italicized in the specification.

4             Dictionary Reference Information Model overview

4.1       General

This document describes the basic infrastructure an OPC UA Information Model may use to reference external dictionaries like IEC Common Data Dictionary or eCl@ss. It defines ObjectTypes, VariableTypes and a ReferenceType and explains how they should be used.

The ObjectTypes are used to represent an external dictionary in an OPC UA AddressSpace. The ReferenceType is used to reference from Nodes in the AddressSpace to the dictionary entries. Such dictionary entries can be seen as external classification or external semantic information.

The type system of OPC UA already provides means to express the semantic of an OPC UA Object. As an example, OPC 10000-100 defines the DeviceType ObjectType expressing that instances of this ObjectType represent devices. Subtypes of the DeviceType are used to add vendor specific semantic. However, the classification and additional semantic of the device in terms of an external data dictionary is not specified further. This document provides means to represent that an Object is for example a differential pressure transmitter in the context of an IEC Common Data Dictionary. This allows clients to automatically retrieve and identify such devices.

This document is an integral part of this standard, that is, the types defined in this document shall be used as defined. However, it is not required but strongly recommended that a Server use the types defined in this document to refer to external dictionaries. The defined types may be subtyped to refine their behaviour.

When a Server references external dictionaries using the types defined in this document, it refers from OPC UA Nodes to dictionary entries. The Server may optionally also provide the hierarchy and content of the external dictionary. Resource consumption needs to be considered, especially in scenarios where the OPC UA Server is part of the firmware of a device.

Note: This version of the document reference Types defined in Amendment OPC 10001-5 and described as amendments to OPC 10001-5. In a future version of this document the Types defined in the Amendment will be included here and not in OPC 10001-5.

4.2       Overview

The types and instances defined in this document are illustrated in Figure 1. The DictionaryEntryType is an abstract base type for dictionary entries. The IrdiDictionaryEntryType and the UriDictionaryEntryType provide concrete types that can be used to represent dictionary entries. The HasDictionaryEntry ReferenceType is used to refer an OPC UA Node to a dictionary entry. The DictionaryFolderType and the Dictionaries Object provide an optional capability to expose the hierarchy of a referenced dictionary.

Figure5_

Figure 1The dictionary reference types

5             OPC UA ObjectTypes

5.1         DictionaryEntryType

This abstract ObjectType is formally defined in OPC 10001-5 for this version of the document.

5.2         DictionaryFolderType

This ObjectType is formally defined in OPC 10001-5 for this version of the document.

5.3         IRDI ISO/IEC 11179-6 conformant DictionaryEntryType

This ObjectType is formally defined in OPC 10001-5 for this version of the document.

5.4         URI based dictionary entry type

This ObjectType is formally defined in OPC 10001-5 for this version of the document.

6             OPC UA ReferenceTypes

6.1         HasDictionaryEntry ReferenceType

This ReferenceType is formally defined in OPC 10001-5 for this version of the document.

7             OPC UA VariableTypes

7.1         MultiStateDictionaryEntryDiscreteBaseType VariableType

The MultiStateDictionaryEntryDiscreteBaseType VariableType is a subtype of the MultiStateValueDiscreteType. It provides dictionary entries for each of the possible states as well as the current state of the MultiStateValueDiscreteType. It is formally defined in Table 1.

Table 1 – MultiStateDictionaryEntryDiscreteBaseType Definition

Attribute

Value

BrowseName

MultiStateDictionaryEntryDiscreteBaseType

IsAbstract

False

ValueRank

Scalar

DataType

Number

References

NodeClass

BrowseName

DataType

TypeDefinition

Modelling
Rule

Subtype of the MultiStateValueDiscreteType defined in OPC 10000-8

HasProperty

Variable

EnumDictionaryEntries

NodeId[][]

PropertyType

Mandatory

HasComponent

Variable

ValueAsDictionaryEntries

NodeId[]

PropertyType

Optional

 

The normal approach of associating DictionaryEntryType Nodes with HasDictionaryEntry References cannot be used with a MultiStateValueDiscreteType VariableType due to the EnumStrings Property being an Array, making this Type necessary. References can however be used for other VariableTypes. For example, the TwoStateDiscreteType can use HasDictionaryEntry References with SourceNode being the TrueState and FalseState Properties and TargetNode being the DictionaryEntry Nodes.

EnumDictionaryEntries is a two-dimensional array of NodeIds. The first dimension is used to list all possible dictionary entry values for the related variable in a specific dictionary (e.g. CDD or eCl@ss). The second dimension is used to reference this dictionary. The size of the first array dimension shall be the same size as the EnumStrings Property.

ValueAsDictionaryEntries provides a list of all dictionary entry values in the different dictionaries related to the current value of the variable. The order of the array entries shall be in the same order used by the EnumDictionaryEntries Property.

If an instance of this type is writeable and the optional ValueAsDictionaryEntries Property is implemented, it shall be writeable as well. Clients writing to the ValueAsDictionaryEntries Property shall use one of the DictionaryEntryType NodeIds defined by the EnumDictionaryEntries Property. This will have the same result as writing the value attribute, but the client does not require knowledge of the values.

The NodeIds represent the dictionary entries and can be generated with dictionary knowledge.

7.2         MultiStateDictionaryEntryDiscreteType VariableType

The MultiStateDictionaryEntryDiscreteType VariableType is a subtype of the MultiStateDictionaryEntryDiscreteBaseType. It requires the ValueAsDictionaryEntries Property. It is formally defined in Table 2.

Table 2 – MultiStateDictionaryEntryDiscreteType Definition

Attribute

Value

BrowseName

MultiStateDictionaryEntryDiscreteType

IsAbstract

False

ValueRank

Scalar

DataType

Number

References

NodeClass

BrowseName

DataType

TypeDefinition

Modelling
Rule

Subtype of the MultiStateDictionaryEntryDiscreteBaseType defined in 7.1

HasComponent

Variable

ValueAsDictionaryEntries

NodeId[]

PropertyType

Mandatory

 

8             OPC UA Objects

8.1         Dictionaries Object

This ObjectType is formally defined in OPC 10001-5 for this version of the document.

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