SIST EN IEC 61158-5-12:2019

SLOVENSKI STANDARD
01-november-2019
Nadomešča:
SIST EN 61158-5-12:2015
Industrijska komunikacijska omrežja - Specifikacije za procesna vodila - 5-12. del:
Definicija opravil na aplikacijski ravni - Elementi tipa 12 (IEC 61158-5-12:2019)
Industrial communication networks - Fieldbus specifications - Part 5-12: Application layer
service definition - Type 12 elements (IEC 61158-5-12:2019)
Industrielle Kommunikationsnetze - Feldbusse - Teil 5-12: Dienstfestlegungen des
Application Layer (Anwendungsschicht) - Typ 12-Elemente (IEC 61158-5-12:2019)
Réseaux de communication industriels - Spécifications des bus de terrain - Partie 5-12 :
Définition des services de la couche application - Éléments de type 12 (IEC 61158-5-
12:2019)
Ta slovenski standard je istoveten z: EN IEC 61158-5-12:2019
ICS:
25.040.40 Merjenje in krmiljenje Industrial process
industrijskih postopkov measurement and control
35.100.70 Uporabniški sloj Application layer
35.110 Omreževanje Networking
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD EN IEC 61158-5-12

NORME EUROPÉENNE
EUROPÄISCHE NORM
June 2019
ICS 25.040.40; 35.100.70; 35.110 Supersedes EN 61158-5-12:2014
English Version
Industrial communication networks - Fieldbus specifications -
Part 5-12: Application layer service definition - Type 12 elements
(IEC 61158-5-12:2019)
Réseaux de communication industriels - Spécifications des Industrielle Kommunikationsnetze - Feldbusse - Teil 5-12:
bus de terrain - Partie 5-12 : Définition des services de la Dienstfestlegungen des Application Layer
couche application - Éléments de type 12 (Anwendungsschicht) - Typ 12-Elemente
(IEC 61158-5-12:2019) (IEC 61158-5-12:2019)
This European Standard was approved by CENELEC on 2019-05-15. CENELEC members are bound to comply with the CEN/CENELEC
Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.
Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC
Management Centre or to any CENELEC member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the
same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the
Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.

European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2019 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN IEC 61158-5-12:2019 E

European foreword
The text of document 65C/947/FDIS, future edition 4 of IEC 61158-5-12, prepared by SC 65C
"Industrial networks" of IEC/TC 65 "Industrial-process measurement, control and automation" was
submitted to the IEC-CENELEC parallel vote and approved by CENELEC as EN IEC 61158-5-
12:2019.
The following dates are fixed:
• latest date by which the document has to be implemented at national (dop) 2020-02-15
level by publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2022-05-15
document have to be withdrawn
This document supersedes EN 61158-5-12:2014.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC shall not be held responsible for identifying any or all such patent rights.

Endorsement notice
The text of the International Standard IEC 61158-5-12:2019 was approved by CENELEC as a
European Standard without any modification.
In the official version, for Bibliography, the following notes have to be added for the standards
indicated:
IEC 61158-2 NOTE Harmonized as EN 61158-2
IEC 61158-4-12 NOTE Harmonized as EN 61158-4-12
IEC 61158-6-12 NOTE Harmonized as EN 61158-6-12
IEC 61784-1 NOTE Harmonized as EN 61784-1
IEC 61784-2 NOTE Harmonized as EN 61784-2

Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments)
applies.
NOTE 1  Where an International Publication has been modified by common modifications, indicated by (mod), the relevant
EN/HD applies.
NOTE 2  Up-to-date information on the latest versions of the European Standards listed in this annex is available here:
www.cenelec.eu.
Publication Year Title EN/HD Year
IEC 61131-3 -  Programmable controllers - Part 3: EN 61131-3 -
Programming languages
IEC 61158-1 2019 Industrial communication networks - EN IEC 61158-1 2019
Fieldbus specifications - Part 1: Overview
and guidance for the IEC 61158 and IEC
61784 series
IEC 61158-3-12 2019 Industrial communication networks - - -
Fieldbus specifications - Part 3-12: Data-
link layer service definition - Type 12
elements
ISO/IEC 646 1991 Information technology; ISO 7-bit coded - -
character set for information interchange
ISO/IEC 7498-1 -  Information technology - Open Systems - -
Interconnection - Basic reference model:
The basic model
ISO/IEC 7498-3 -  Information technology - Open Systems - -
Interconnection - Basic reference model:
Naming and addressing
ISO/IEC/IEEE 8802-3 -  Standard for Ethernet - -
ISO/IEC 9545 -  Information technology - Open Systems - -
Interconnection - Application layer
structure
ISO/IEC 10646 -  Information technology - Universal Coded - -
Character Set (UCS)
ISO/IEC 10731 -  Information technology - Open Systems - -
Interconnection - Basic Reference Model -
Conventions for the definition of OSI
services
ISO/IEC/IEEE 60559 -  Information technology - Microprocessor - -
Systems - Floating-Point arithmetic
IEEE 802.1D -  IEEE Standard for local and metropolitan - -
area networks - Media Access Control
(MAC) Bridges
IETF RFC 791 -  Internet Protocol - DARPA Internet - -
Program Protocol Specification

IEC 61158-5-12 ®
Edition 4.0 2019-04
INTERNATIONAL
STANDARD
Industrial communication networks – Fieldbus specifications –

Part 5-12: Application layer service definition – Type 12 elements

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 25.040.40; 35.100.70; 35.110 ISBN 978-2-8322-6747-9

– 2 – IEC 61158-5-12:2019 © IEC 2019
CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope . 8
1.1 General . 8
1.2 Specifications . 9
1.3 Conformance . 9
2 Normative references . 9
3 Terms, definitions, symbols, abbreviations and conventions . 10
3.1 Reference model terms and definitions . 10
3.2 Service convention terms and definitions . 11
3.3 Application layer and data-link service terms and definitions . 11
3.4 Common symbols and abbreviations . 15
3.5 Conventions . 16
4 Concepts . 17
4.1 Common concepts . 17
4.2 Type specific concepts . 17
4.2.1 Operating principle . 17
4.2.2 Communication model overview . 18
4.2.3 Application layer element description . 18
4.2.4 Slave reference model . 20
4.2.5 Master reference model . 22
5 Data type ASE . 24
5.1 General . 24
5.2 Formal definition of data type objects . 24
5.3 FAL defined data types . 24
5.3.1 Fixed length types . 24
5.3.2 String types . 32
5.3.3 GUID Types . 33
5.4 Data type ASE service specification . 33
6 Communication model specification . 33
6.1 ASEs . 33
6.1.1 Process data ASE. 33
6.1.2 SII ASE . 40
6.1.3 Isochronous ASE . 49
6.1.4 CoE ASE . 52
6.1.5 EoE ASE . 85
6.1.6 FoE ASE. 94
6.1.7 MBX ASE . 100
6.2 AR . 105
6.2.1 Overview . 105
6.2.2 AR control class specification . 110
6.2.3 AR service specification . 114
Bibliography . 117

Figure 1 – Producer consumer model. 19
Figure 2 – Client server model . 19

IEC 61158-5-12:2019 © IEC 2019 – 3 –
Figure 3 – Server triggered invocation . 19
Figure 4 – Slave reference model . 20
Figure 5 – Simple slave device . 21
Figure 6 – Complex slave device . 22
Figure 7 – Master functional overview . 23
Figure 8 – Process output data sequence . 34
Figure 9 – Process input data sequence . 35
Figure 10 – CoE server model . 52
Figure 11 – Successful single SDO-Download sequence . 57
Figure 12 – Unsuccessful single SDO-Download sequence . 58
Figure 13 – Successful segmented SDO-Download sequence . 58
Figure 14 – Successful single SDO-Upload sequence . 59
Figure 15 – Unsuccessful single SDO-Upload sequence . 59
Figure 16 – Successful segmented SDO-Upload sequence . 60
Figure 17 – SDO information sequence . 61
Figure 18 – Emergency service . 62
Figure 19 – Command sequence. 63
Figure 20 – PDO mapping . 64
Figure 21 – Sync manager PDO assigment . 64
Figure 22 – RxPDO service . 66
Figure 23 – TxPDO service . 66
Figure 24 – RxPDO remote transmission sequence . 67
Figure 25 – TxPDO remote transmission sequence . 67
Figure 26 – EoE sequence . 87
Figure 27 – FoE read sequence with success . 94
Figure 28 – FoE read sequence with error . 95
Figure 29 – FoE write sequence with success . 95
Figure 30 – FoE write sequence with error . 96
Figure 31 – FoE write sequence with busy . 96
Figure 32 – Successful AL control sequence . 106
Figure 33 – Unsuccessful AL control sequence . 107
Figure 34 – AL state changed sequence . 108

Table 1 – Process output data . 37
Table 2 – Process input data . 38
Table 3 – Update process input data . 39
Table 4 – SII read . 47
Table 5 – SII write. 48
Table 6 – SII reload . 49
Table 7 – Allocation of SDO areas . 53
Table 8 – SDO download expedited . 71
Table 9 – SDO download normal . 72
Table 10 – Download SDO segment . 73

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Table 11 – SDO upload expedited. 74
Table 12 – SDO upload normal . 75
Table 13 – Upload SDO segment . 76
Table 14 – Abort SDO transfer . 76
Table 15 – Get OD list . 77
Table 16 – OD list segment . 78
Table 17 – Get object description. 79
Table 18 – Get entry description . 80
Table 19 – Object entry segment . 82
Table 20 – Emergency . 83
Table 21 – RxPDO . 84
Table 22 – TxPDO . 84
Table 23 – RxPDO remote transmission. 85
Table 24 – TxPDO remote transmission . 85
Table 25 – Initiate EoE . 90
Table 26 – EoE fragment . 91
Table 27 – Set IP parameter . 92
Table 28 – Set address filter . 93
Table 29 – FoE read . 98
Table 30 – FoE write . 98
Table 31 – FoE data . 99
Table 32 – FoE ack . 99
Table 33 – FoE busy . 100
Table 34 – FoE error . 100
Table 35 – MBX read . 102
Table 36 – MBX write . 103
Table 37 – MBX read upd . 104
Table 38 – AL management and ESM service primitives . 105
Table 39 – AL control . 115
Table 40 – AL state change . 116

IEC 61158-5-12:2019 © IEC 2019 – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
INDUSTRIAL COMMUNICATION NETWORKS –
FIELDBUS SPECIFICATIONS –
Part 5-12: Application layer service definition –
Type 12 elements
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as
“IEC Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee
interested in the subject dealt with may participate in this preparatory work. International, governmental and
non-governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates
closely with the International Organization for Standardization (ISO) in accordance with conditions determined
by agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of
IEC Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other
IEC Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
Attention is drawn to the fact that the use of the associated protocol type is restricted by its
intellectual-property-right holders. In all cases, the commitment to limited release of
intellectual-property-rights made by the holders of those rights permits a layer protocol type to
be used with other layer protocols of the same type, or in other type combinations explicitly
authorized by its intellectual-property-right holders.
NOTE Combinations of protocol types are specified in IEC 61784-1 and IEC 61784-2.
International Standard IEC 61158-5-12 has been prepared by subcommittee 65C: Industrial
networks, of IEC technical committee 65: Industrial-process measurement, control and
automation.
This fourth edition cancels and replaces the third edition published in 2014. This edition
constitutes a technical revision.

– 6 – IEC 61158-5-12:2019 © IEC 2019
This edition includes the following significant technical changes with respect to the previous
edition:
• Technical corrections; and
• Editorial improvements for clarification.
The text of this International Standard is based on the following documents:
FDIS Report on voting
65C/947/FDIS 65C/950/RVD
Full information on the voting for the approval of this International Standard can be found in
the report on voting indicated in the above table.
This publication has been drafted in accordance with ISO/IEC Directives, Part 2.
A list of all parts of the IEC 61158 series, published under the general title Industrial
communication networks – Fieldbus specifications, can be found on the IEC web site.
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
A bilingual version of this publication may be issued at a later date.

IEC 61158-5-12:2019 © IEC 2019 – 7 –
INTRODUCTION
This document is one of a series produced to facilitate the interconnection of automation
system components. It is related to other standards in the set as defined by the “three-layer”
fieldbus reference model described in IEC 61158-1.
The application service is provided by the application protocol making use of the services
available from the data-link or other immediately lower layer. This document defines the
application service characteristics that fieldbus applications and/or system management may
exploit.
Throughout the set of fieldbus standards, the term “service” refers to the abstract capability
provided by one layer of the OSI Basic Reference Model to the layer immediately above.
Thus, the application layer service defined in this document is a conceptual architectural
service, independent of administrative and implementation divisions.

– 8 – IEC 61158-5-12:2019 © IEC 2019
INDUSTRIAL COMMUNICATION NETWORKS –
FIELDBUS SPECIFICATIONS –
Part 5-12: Application layer service definition –
Type 12 elements
1 Scope
1.1 General
The fieldbus Application Layer (FAL) provides user programs with a means to access the
fieldbus communication environment. In this respect, the FAL can be viewed as a “window
between corresponding application programs.”
This part of IEC 61158 provides common elements for basic time-critical and non-time-critical
messaging communications between application programs in an automation environment and
material specific to Type 12 fieldbus. The term “time-critical” is used to represent the
presence of a time-window, within which one or more specified actions are required to be
completed with some defined level of certainty. Failure to complete specified actions within
the time window risks failure of the applications requesting the actions, with attendant risk to
equipment, plant and possibly human life.
This International Standard defines in an abstract way the externally visible service provided
by the different Types of the fieldbus Application Layer in terms of
a) an abstract model for defining application resources (objects) capable of being
manipulated by users via the use of the FAL service,
b) the primitive actions and events of the service,
c) the parameters associated with each primitive action and event, and the form which they
take, and
d) the interrelationship between these actions and events, and their valid sequences.
The purpose of this document is to define the services provided to
a) the FAL user at the boundary between the user and the Application Layer of the Fieldbus
Reference Model, and
b) Systems Management at the boundary between the Application Layer and Systems
Management of the Fieldbus Reference Model.
This document specifies the structure and services of the IEC fieldbus Application Layer, in
conformance with the OSI Basic Reference Model (ISO/IEC 7498) and the OSI Application
Layer Structure (ISO/IEC 9545).
FAL services and protocols are provided by FAL application-entities (AE) contained within the
application processes. The FAL AE is composed of a set of object-oriented Application
Service Elements (ASEs) and a Layer Management Entity (LME) that manages the AE. The
ASEs provide communication services that operate on a set of related application process
object (APO) classes. One of the FAL ASEs is a management ASE that provides a common
set of services for the management of the instances of FAL classes.
Although these services specify, from the perspective of applications, how request and
responses are issued and delivered, they do not include a specification of what the requesting
and responding applications are to do with them. That is, the behavioral aspects of the
applications are not specified; only a definition of what requests and responses they can

IEC 61158-5-12:2019 © IEC 2019 – 9 –
send/receive is specified. This permits greater flexibility to the FAL users in standardizing
such object behavior. In addition to these services, some supporting services are also defined
in this document to provide access to the FAL to control certain aspects of its operation.
1.2 Specifications
The principal objective of this document is to specify the characteristics of conceptual
application layer services suitable for time-critical communications, and thus supplement the
OSI Basic Reference Model in guiding the development of application layer protocols for time-
critical communications.
A secondary objective is to provide migration paths from previously-existing industrial
communications protocols. It is this latter objective which gives rise to the diversity of services
standardized as the various Types of IEC 61158, and the corresponding protocols
standardized in subparts of IEC 61158-6.
This specification may be used as the basis for formal Application Programming-Interfaces.
Nevertheless, it is not a formal programming interface, and any such interface will need to
address implementation issues not covered by this specification, including
a) the sizes and octet ordering of various multi-octet service parameters, and
b) the correlation of paired request and confirm, or indication and response, primitives.
1.3 Conformance
This document does not specify individual implementations or products, nor does it constrain
the implementations of application layer entities within industrial automation systems.
There is no conformance of equipment to this application layer service definition standard.
Instead, conformance is achieved through implementation of conforming application layer
protocols that fulfill any given Type of application layer services as defined in this document.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their
content constitutes requirements of this document. For dated references, only the edition
cited applies. For undated references, the latest edition of the referenced document (including
any amendments) applies.
NOTE All parts of the IEC 61158 series, as well as IEC 61784-1 and IEC 61784-2 are maintained simultaneously.
Cross-references to these documents within the text therefore refer to the editions as dated in this list of normative
references.
IEC 61131-3, Programmable controllers – Part 3: Programming languages
IEC 61158-1:2019, Industrial communication networks – Fieldbus specifications – Part 1:
Overview and guidance for the IEC 61158 and IEC 61784 series
IEC 61158-3-12:2019, Industrial communication networks – Fieldbus specifications –
Part 3-12: Data-link layer service definition – Type 12 elements
ISO/IEC 646:1991, Information technology – ISO 7-bit coded character set for information
interchange
ISO/IEC 7498-1, Information technology – Open Systems Interconnection – Basic Reference
Model: The Basic Model
– 10 – IEC 61158-5-12:2019 © IEC 2019
ISO/IEC 7498-3, Information technology – Open Systems Interconnection – Basic Reference
Model: Naming and addressing
ISO/IEC/IEEE 8802-3, Information technology – Telecommunications and information
exchange between systems – Local and metropolitan area networks – Specific requirements –
Part 3: Standard for Ethernet
ISO/IEC 9545, Information technology – Open Systems Interconnection – Application Layer
structure
ISO/IEC 10646, Information technology – Universal Coded Character Set (UCS)
ISO/IEC 10731, Information technology – Open Systems Interconnection – Basic Reference
Model – Conventions for the definition of OSI services
ISO/IEC/IEEE 60559, Information technology – Microprocessor Systems – Floating-Point
arithmetic
IEEE Std 802.1D, IEEE standard for local and metropolitan area networks – Media access
control (MAC) Bridges; available at http://www.ieee.org> [viewed 2018-09-11]
IETF RFC 791, Internet Protocol darpa internet program protocol specification; available at
http://www.ietf.org> [viewed 2018-09-11]
3 Terms, definitions, symbols, abbreviations and conventions
For the purposes of this document, the following terms, definitions, symbols, abbreviations
and conventions apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1 Reference model terms and definitions
This document is based in part on the concepts developed in ISO/IEC 7498-1 and
ISO/IEC 7498-3, and makes use of the following terms defined therein:
3.1.1 correspondent (N)-entities
[ISO/IEC 7498-1]
correspondent AL-entities  (N=7)
3.1.2 (N)-entity [ISO/IEC 7498-1]
AL-entity  (N=7)
3.1.3 (N)-layer [ISO/IEC 7498-1]
AL-layer  (N=7)
3.1.4 layer-management
[ISO/IEC 7498-1]
3.1.5 peer-entities [ISO/IEC 7498-1]
3.1.6 primitive name
[ISO/IEC 7498-3]
3.1.7 AL-protocol [ISO/IEC 7498-1]
3.1.8 AL-protocol-data-unit [ISO/IEC 7498-1]

IEC 61158-5-12:2019 © IEC 2019 – 11 –
3.1.9 reset [ISO/IEC 7498-1]
3.1.10 routing
[ISO/IEC 7498-1]
3.1.11 segmenting [ISO/IEC 7498-1]
3.1.12 (N)-service [ISO/IEC 7498-1]
AL-service  (N=7)
3.1.13 AL-service-data-unit
[ISO/IEC 7498-1]
3.1.14 AL-simplex-transmission [ISO/IEC 7498-1]
3.1.15 AL-subsystem
[ISO/IEC 7498-1]
3.1.16 systems-management [ISO/IEC 7498-1]
3.1.17 AL-user-data
[ISO/IEC 7498-1]
3.2 Service convention terms and definitions
This document also makes use of the following terms defined in ISO/IEC 10731 as they apply
to the data-link layer:
3.2.1 acceptor
3.2.2 asymmetrical service
3.2.3 confirm (primitive);
requestor.deliver (primitive)
3.2.4 deliver (primitive)
3.2.5 AL-service-primitive;
primitive
3.2.6 AL-service-provider
3.2.7 AL-service-user
3.2.8 indication (primitive);
acceptor.deliver (primitive)
3.2.9 request (primitive);
requestor.submit (primitive)
3.2.10 requestor
3.2.11 response (primitive);
acceptor.submit (primitive)
3.2.12 submit (primitive)
3.2.13 symmetrical service
3.3 Application layer and data-link service terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.3.1
application
function or data structure for which data is consumed or produced
3.3.2
application objects
multiple object classes that manage and provide a run time exchange of messages across the
network and within the network device

– 12 – IEC 61158-5-12:2019 © IEC 2019
3.3.3
basic slave
slave device that supports only physical addressing of data
3.3.4
bit
unit of information consisting of a 1 or a 0
Note 1 to entry: This is the smallest data unit that can be transmitted.
3.3.5
client
object which uses the services of another (server) object to perform a task
3.3.6
client
initiator of a message to which a server reacts
3.3.7
communication object
component that manage and provide a run time exchange of messages across the network
3.3.8
connection
logical binding between two application objects within the same or different devices
3.3.9
cyclic
events which repeat in a regular and repetitive manner
3.3.10
data
generic term used to refer to any information carried over a fieldbus
3.3.11
data consistency
means for coherent transmission and access of the input- or output-data object between and
within client and server
3.3.12
data type
relation between values and encoding for data of that type
Note 1 to entry: The data type definitions of IEC 61131-3 apply.
3.3.13
data type object
entry in the object dictionary indicating a data type
3.3.14
default gateway
device with at least two interfaces in two different IP subnets acting as router for a subnet.
3.3.15
device
physical entity connected to the fieldbus composed of at least one communication element
(the network element) and which may have a control element and/or a final element
(transducer, actuator, etc.)
IEC 61158-5-12:2019 © IEC 2019 – 13 –
3.3.16
device profile
collection of device dependent information and functionality providing consistency between
similar devices of the same device
3.3.17
diagnosis information
all data available at the server for maintenance purposes
3.3.18
distributed clocks
method to synchronize slaves and maintain a global time base
3.3.19
error
discrepancy between a computed, observed or measured value or condition and the specified
or theoretically correct value or condition
3.3.20
error class
general grouping for related error definitions and corresponding error codes
3.3.21
error code
identification of a specific type of error within an error class
3.3.22
event
instance of a change of conditions
3.3.23
fieldbus memory management unit
function that establishes one or several correspondences between logical addresses and
physical memory
3.3.24
fieldbus memory management unit entity
single element of the fieldbus memory management unit: one correspondence between a
coherent logical address space and a coherent physical memory location
3.3.25
frame
denigrated synonym for DLPDU
3.3.26
full slave
slave device that supports both physical and logical addressing of data
3.3.27
index
address of an object within an application process
3.3.28
interface
shared boundary between two functional units, defined by functional characteristics, signal
characteristics, or other characteristics as appropriate

– 14 – IEC 61158-5-12:2019 © IEC 2019
3.3.29
little endian
method for data representation of numbers greater 8 bit where the least significant octet is
transmitted first
3.3.30
master
device that controls the data transfer on the network and initiates the media access of the
slaves by sending messages and that constitutes the interface to the control system
3.3.31
mapping
correspondence between two objects in that way that one object is part of the other object
3.3.32
mapping parameters
set of values defining the correspondence between application objects and process data
objects
3.3.33
medium
cable, optical fibre, or other means by which communication signals are transmitted between
two or more points
Note 1 to entry: "media" is used as the plural of medium.
3.3.34
message
ordered series of octets intended to convey information
Note 1 to entry: Normally used to convey information between peers at the application layer.
3.3.35
network
set of nodes connected by some type of communication medium, including any intervening
repeaters, bridges, routers and lower-layer gateways
3.3.36
node
a) single DL-entity as it appears on one local link
b) end-point of a link in a network or a point at which two or more links meet
[SOURCE: IEC 61158-2, for option b), with some wording adjustment]
3.3.37
object
abstract representation of a particular component within a device
Note 1 to entry: An object can be
a) an abstract representation of the capabilities of a device. Objects can be composed of any or all of the
following components:
1) data (information which changes with time);
2) configuration (parameters for behavior);
3) methods (things that can be done using data and configuration).
b) a collection of related data (in the form of variables) and methods (procedures) for operating on that data that
have clearly defined interface and behavior.

IEC 61158-5-12:2019 © IEC 2019 – 15 –
3.
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