EN 61158-6-18:2012

Industrial communication networks - Fieldbus specifications - Part 6-18: Application layer protocol specification - Type 18 elements

IEC 61158-6-18:2010(E) specifies the protocol of the Type 18 fieldbus application layer, in conformance with the OSI Basic Reference Model (ISO/IEC 7498-1) and the OSI application layer structure (ISO/IEC 9545). It defines the protocol provided to define the wire-representation of the service primitives defined in IEC 61158-5-18:2010, and the externally visible behavior associated with their transfer. This second edition cancels and replaces the first edition published in 2007 and constitutes a technical revision. The main changes with respect to the previous edition are: - editorial corrections; - addition of cyclic data segmenting.

Industrielle Kommunikationsnetze - Feldbusse - Teil 6-18: Protokollspezifikation des Application Layer (Anwendungsschicht) - Typ 18-Elemente

Réseaux de communication industriels - Spécifications des bus de terrain - Partie 6-18: Spécification des protocoles des couches d'application - Eléments de type 18

L'IEC 61158-6-18:2010 fournit des éléments communs pour les communications en temps critique ou non entre des programmes d'application dans un environnement et avec un matériel d'automatisation propres aux bus de terrain de type 18. Le terme "en temps critique" signale l'existence d'une fenêtre temporelle dans laquelle est exigée la réalisation d'une ou de plusieurs actions spécifiées, avec un niveau de certitude défini. La non-réalisation des actions spécifiées dans la fenêtre temporelle induit un risque de défaillance des applications qui exigent ces actions, avec les risques afférents pour l'équipement, les installations et éventuellement la vie humaine. La présente norme définit les interactions entre les applications distantes ainsi que le comportement, visible par un observateur externe, assuré par la couche Application de bus de terrain de type 18, en termes a) de syntaxe abstraite formelle définissant les unités de données de protocole de couche application, acheminées entre les entités d'application en communication; b) de syntaxe de transfert définissant les règles de codage qui s'appliquent aux unités de données de protocole de couche application; c) de la machine à état de contexte application définissant le comportement de service application visible entre des entités d'application engagées dans une communication; d) de machines à état de relations d'applications définissant le comportement de communication visible entre les entités d'application en communication.

Industrijska komunikacijska omrežja - Specifikacije za procesno vodilo - 6-18. del: Specifikacija protokola na aplikacijskem nivoju - Elementi tipa 18 (IEC 61158-6-18:2010)

Aplikacijski nivo procesnih vodil (FAL) omogoča uporabniškim programom dostop do komunikacijskega okolja procesnih vodil. Glede na to je mogoče aplikacijski nivo procesnih vodil šteti za »okno med ustreznimi aplikacijami«. Ta standard določa skupne elemente za osnovne časovno kritične in časovno nekritične sporočilne komunikacije med aplikacijami v avtomatizacijskem okolju in material, specifičen za procesna vodila tipa 18. Izraz »časovno kritičen« se uporablja za predstavitev prisotnosti časovnega okna, v okviru katerega se zahteva dokončanje enega ali več opredeljenih dejanj z določeno stopnjo gotovosti. Zaradi neuspešnega dokončanja opredeljenih dejanj v časovnem oknu je možna odpoved aplikacij, ki zahtevajo dejanja, pri čemer so ogroženi oprema, obrat in morda človeška življenja. Ta standard opredeljuje interakcije med oddaljenimi aplikacijami in določa zunanje vidno vedenje, ki ga zagotavlja aplikacijski nivo procesnih vodil tipa 18 v zvezi z a) formalno abstraktno sintakso, ki opredeljuje podatkovne enote protokola aplikacijskega nivoja, ki se prenašajo med aplikacijskimi osebki, ki komunicirajo, b) prenosno sintakso, ki opredeljuje pravila kodiranja, ki se uporabljajo za podatkovne enote protokola aplikacijskega nivoja, c) strojem stanj aplikacijskega konteksta, ki opredeljuje vedenje aplikacijskega opravila, vidnega med aplikacijskimi osebki, ki komunicirajo, in d) stroji stanj aplikacijskega razmerja, ki opredeljujejo komunikacijsko vedenje med aplikacijskimi osebki, ki komunicirajo. Namen tega standarda je opredeliti protokol za a) določitev žične predstavitve primitivov opravil iz standarda IEC 61158-5-18 in b) določitev zunanje vidnega vedenja, povezanega z njihovim prenosom. Ta standard določa protokol aplikacijskega nivoja procesnih vodil tipa 18 v skladu z osnovnim referenčnim modelom OSI (ISO/IEC 7498-1) in strukturo aplikacijskega nivoja OSI (ISO/IEC 9545).

General Information

• Status: Published
• Publication Date: 21-Jun-2012
• Withdrawal Date: 27-Mar-2015
• ICS: 25.040.40 - Industrial process measurement and control
• ICS: 35.100.70 - Application layer
• ICS: 35.110 - Networking
• Technical Committee: CLC/TC 65X - Industrial-process measurement, control and automation
• Drafting Committee: IEC/SC 65C - IEC_SC_65C
• Current Stage: 6060 - Document made available - Publishing
• Start Date: 22-Jun-2012
• Completion Date: 22-Jun-2012
• Mandate: M/490 - Standardisation mandate to the European Standardisation Organisations (ESOs) to support European Smart Grid deployment
• Ref Project: SIST EN 61158-6-18:2012 - Industrial communication networks - Fieldbus specifications - Part 6-18: Application layer protocol specification - Type 18 elements (IEC 61158-6-18:2010)

Relations

• Replaces: EN 61158-6-18:2008 - Industrial communication networks - Fieldbus specifications - Part 6-18: Application layer protocol specification - Type 18 elements
• Effective Date: 28-Jan-2023

Overview

EN 61158-6-18:2012 - titled Industrial communication networks - Fieldbus specifications - Part 6-18: Application layer protocol specification - Type 18 elements - is the CENELEC adoption of IEC 61158-6-18:2010. The standard specifies the application layer protocol (wire-level encoding and behaviour) for Type 18 fieldbus elements. It maps the service primitives defined in IEC 61158-5-18 to their wire representation and defines the externally visible behavior of their transfer. The 2012 edition is a technical revision of the 2008 edition and includes editorial corrections and the addition of cyclic data segmenting. The protocol is defined in conformance with the OSI Basic Reference Model (ISO/IEC 7498-1) and the OSI application layer structure (ISO/IEC 9545).

Key topics and technical requirements

• Application layer protocol specification: precise encoding (transfer syntax) and abstract syntax for Type 18 PDUs (Protocol Data Units).
• Mapping of service primitives: wire-level definitions for the service primitives given in IEC 61158-5-18 (device manager, connection manager, cyclic and acyclic transmissions).
• Protocol machines and state machines: structure and behavior of FAL service protocol machine (FSPM), AR protocol machine (ARPM - master and slave variants), and DLL mapping protocol machine (DMPM).
• Cyclic and acyclic transmission handling: definitions for cyclic transmission PDUs, including the newly added cyclic data segmenting capability, and message/data encoding for acyclic transfers.
• Attribute and command encodings: tables and formats for device/connection/cyclic attributes, command headers, system info, memory read/write and line test commands.
• Conformance and interoperability: alignment with OSI conventions and normative references to ensure consistent implementation across vendors.

Applications and users

This standard is essential for:

• Fieldbus device manufacturers implementing the Type 18 application layer in firmware or hardware.
• Automation system integrators who need to ensure interoperability between Type 18 devices and networks.
• Protocol stack developers and vendors creating compliant application-layer implementations.
• Test laboratories and certification bodies validating wire-level conformance and interoperability.
• Control engineers designing industrial process control systems that rely on deterministic cyclic data exchange.

Practical use-cases include deterministic cyclic I/O exchange, configuration and device management over a Type 18 fieldbus, and integrated systems where strict protocol conformance is required for cross-vendor interoperability.

Related standards

• IEC 61158-5-18 - Application layer service definition (normative mapping of service primitives)
• IEC 61158-3-18, IEC 61158-4-18 - other parts of the Type 18 specification
• ISO/IEC 7498-1, ISO/IEC 9545 - OSI Basic Reference Model and application layer structure

Keywords: EN 61158-6-18:2012, IEC 61158-6-18, fieldbus, application layer protocol, Type 18, cyclic data segmenting, industrial communication networks, OSI model, fieldbus interoperability.

Standards Content (Sample)

SLOVENSKI STANDARD
01-september-2012
1DGRPHãþD
SIST EN 61158-6-18:2008
Industrijska komunikacijska omrežja - Specifikacije za procesno vodilo - 6-18. del:
Specifikacija protokola na aplikacijskem nivoju - Elementi tipa 18 (IEC 61158-6-
18:2010)
Industrial communication networks - Fieldbus specifications - Part 6-18: Application layer
protocol specification - Type 18 elements (IEC 61158-6-18:2010)
Industrielle Kommunikationsnetze - Feldbusse - Teil 6-18: Protokollspezifikation des
Application Layer (Anwendungsschicht) - Typ 18-Elemente (IEC 61158-6-18:2010)
Réseaux de communication industriels - Spécifications des bus de terrain - Partie 6-18:
Spécification des protocoles des couches d'application - Eléments de type 18 (CEI
61158-6-18:2010)
Ta slovenski standard je istoveten z: EN 61158-6-18:2012
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 61158-6-18
NORME EUROPÉENNE
June 2012
EUROPÄISCHE NORM
ICS 25.040.40; 35.100.70; 35.110 Supersedes EN 61158-6-18:2008

English version
Industrial communication networks -
Fieldbus specifications -
Part 6-18: Application layer protocol specification -
Type 18 elements
(IEC 61158-6-18:2010)
Réseaux de communication industriels -  Industrielle Kommunikationsnetze -
Spécifications des bus de terrain - Feldbusse -
Partie 6-18: Spécification des protocoles Teil 6-18: Protokollspezifikation des
des couches d'application - Application Layer (Anwendungsschicht) -
Eléments de type 18 Typ 18-Elemente
(CEI 61158-6-18:2010) (IEC 61158-6-18:2010)

This European Standard was approved by CENELEC on 2012-03-28. 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, Romania, Slovakia, Slovenia,
Spain, Sweden, Switzerland, Turkey and the United Kingdom.

CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung

Management Centre: Avenue Marnix 17, B - 1000 Brussels

© 2012 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 61158-6-18:2012 E
Foreword
The text of document 65C/607/FDIS, future edition 2 of IEC 61158-6-18, 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 61158-6-18:2012.

The following dates are fixed:
(dop) 2012-12-28
• latest date by which the document has
to be implemented at national level by
publication of an identical national
standard or by endorsement
• latest date by which the national (dow) 2015-03-28

standards conflicting with the
document have to be withdrawn
This document supersedes EN 61158-6-18:2008.
18:2008:
– editorial corrections;
– addition of cyclic data segmenting.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC [and/or CEN] shall not be held responsible for identifying any or all such patent
rights.
Endorsement notice
The text of the International Standard IEC 61158-6-18:2010 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/TR 61158-1:2010 NOTE  Harmonized as CLC/TR 61158-1:2010 (not modified).
IEC 61158-3-18:2007 NOTE  Harmonized as EN 61158-3-18:2008 (not modified).
IEC 61158-4-18:2010 NOTE  Harmonized as EN 61158-4-18:2012 (not modified).

- 3 - EN 61158-6-18:2012
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications

The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.

NOTE  When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD
applies.
Publication Year Title EN/HD Year

IEC 61158-5-18 2010 Industrial communication networks - Fieldbus EN 61158-5-18 2012
specifications -
Part 5-18: Application layer service definition -
Type 18 elements
ISO/IEC 7498-1 - Information technology - Open Systems - -
Interconnection - Basic Reference Model:
The Basic Model
ISO/IEC 8822 - Information technology - Open Systems - -
Interconnection - Presentation service
definition
ISO/IEC 8824-1 - Information technology - Abstract Syntax - -
Notation One (ASN.1): Specification of basic
notation
ISO/IEC 9545 - Information technology - Open Systems - -
Interconnection - Application Layer structure

ISO/IEC 10731 - Information technology - Open Systems - -
Interconnection - Basic reference model -
Conventions for the definition of OSI services

IEC 61158-6-18 ®
Edition 2.0 2010-08
INTERNATIONAL
STANDARD
Industrial communication networks – Fieldbus specifications –
Part 6-18: Application layer protocol specification – Type 18 elements

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
XA
ICS 25.04.40; 35.100.70; 35.110 ISBN 978-2-88912-132-8
– 2 – 61158-6-18 © IEC:2010(E)
CONTENTS
FOREWORD.5
INTRODUCTION.7
1 Scope.8
1.1 General .8
1.2 Specifications.8
1.3 Conformance.9
2 Normative references .9
3 Terms and definitions .9
3.1 Terms and definitions from other ISO/IEC standards .9
3.2 Other terms and definitions .10
3.3 Abbreviations and symbols.16
3.4 Additional abbreviations and symbols for type 18 .16
3.5 Conventions .17
4 Abstract syntax.17
4.1 M1 device manager PDU abstract syntax .17
4.2 M2 device manager PDU abstract syntax .17
4.3 S1 device manager PDU abstract syntax.18
4.4 S2 device manager PDU abstract syntax.18
4.5 M1 connection manager PDU abstract syntax.18
4.6 M2 connection manager PDU abstract syntax.19
4.7 S1 connection manager PDU abstract syntax .19
4.8 S2 connection manager PDU abstract syntax .20
4.9 M1 cyclic transmission PDU abstract syntax.20
4.10 M2 cyclic transmission PDU abstract syntax.20
4.11 S1 cyclic transmission PDU abstract syntax .21
4.12 S2 cyclic transmission PDU abstract syntax .21
4.13 Acyclic transmission PDU abstract syntax .21
5 Transfer syntax .22
5.1 M1 device manager PDU encoding.22
5.2 M2 device manager PDU encoding.25
5.3 S1 device manager PDU encoding .26
5.4 S2 device manager PDU encoding .26
5.5 M1 connection manager PDU encoding .27
5.6 M2 connection manager PDU encoding .31
5.7 S1 connection manager PDU encoding.32
5.8 S2 connection manager PDU encoding.33
5.9 M1 cyclic transmission PDU encoding .33
5.10 M2 cyclic transmission PDU encoding .35
5.11 S1 cyclic transmission PDU encoding.36
5.12 S2 cyclic transmission PDU encoding.37
5.13 Acyclic transmission PDU encoding.38
6 Structure of FAL protocol state machines .45
7 AP-context state machine.47
8 FAL service protocol machine (FSPM).47
8.1 Overview .47
8.2 FAL service primitives .47

61158-6-18 © IEC:2010(E) – 3 –
9 AR protocol machine (ARPM) .48
9.1 Overview .48
9.2 M1 master ARPM .49
9.3 M2 master ARPM .53
9.4 Slave ARPM.56
10 DLL mapping protocol machine (DMPM).59
10.1 Overview .59
10.2 Primitives received from the ARPM .59
10.3 Indications received from the DL .59
Bibliography.60

Figure 1 – Parameter block 1 command parameter field.40
Figure 2 – Parameter block 2 command parameter field.41
Figure 3 – Relationships among protocol machines and adjacent layers .46
Figure 4 – ARPM M1 master AR state diagram .49
Figure 5 – ARPM M2 master AR state diagram .53
Figure 6 – ARPM slave AR state diagram .56

Table 1 – M1 device manager attribute format .17
Table 2 – M2 device manager attribute format .17
Table 3 – S1 device manager attribute format.18
Table 4 – S2 device manager attribute format.18
Table 5 – M1 connection manager attribute format.18
Table 6 – M2 connection manager attribute format.19
Table 7 – S1 connection manager attribute format .20
Table 8 – S2 connection manager attribute format .20
Table 9 – M1 cyclic transmission attribute format.20
Table 10 – M2 cyclic transmission attribute format.21
Table 11 – S1 cyclic transmission attribute format .21
Table 12 – S2 cyclic transmission attribute format .21
Table 13 – Acyclic transmission attribute format .21
Table 14 – M1 device manager attribute encoding .23
Table 15 – M2 device manager attribute encoding .25
Table 16 – S1 device manager attribute encoding.26
Table 17 – S2 device manager attribute encoding.27
Table 18 – M1 connection manager attribute encoding .28
Table 19 – M2 connection manager attribute encoding .31
Table 20 – S1 connection manager attribute encoding .32
Table 21 – S2 connection manager attribute encoding .33
Table 22 – M1 cyclic transmission attribute encoding.34
Table 23 – M2 cyclic transmission attribute encoding.36
Table 24 – S1 cyclic transmission attribute encoding .36
Table 25 – S2 cyclic transmission attribute encoding .38
Table 26 – Acyclic transmission – message data encoding .38

– 4 – 61158-6-18 © IEC:2010(E)
Table 27 – Command header format .39
Table 28 – Command codes .39
Table 29 – System information command parameter field .42
Table 30 – System information command parameter field .42
Table 31 – System information command parameter field .42
Table 32 – System information command parameter field .43
Table 33 – Line test command parameter field.43
Table 34 – Memory read command parameter field.44
Table 35 – Memory write command parameter field .45
Table 36 – FSPM events.48
Table 37 – M1 master state-event table 1 – events .51
Table 38 – M1 master state-event table 2 – receipt of FSPM service primitives .51
Table 39 – M1 master state-event table 3 – receipt of DMPM service primitives.53
Table 40 – M2 master state-event table 1 – events .54
Table 41 – M2 master state-event table 2 – receipt of FSPM service primitives .55
Table 42 – M2 master state-event table 3 – receipt of DMPM service primitives.55
Table 43 – S1 connect monitoring time .57
Table 44 – S2 connect monitoring time .57
Table 45 – Slave state-event table 1 – events.58
Table 46 – Slave state-event table 2 – receipt of FSPM service primitives .58
Table 47 – Slave state-event table 3 – receipt of DMPM service primitives .58
Table 48 – ARPM to DL mapping .59
Table 49 – DL to ARPM mapping .59

61158-6-18 © IEC:2010(E) – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
INDUSTRIAL COMMUNICATION NETWORKS –
FIELDBUS SPECIFICATIONS –
Part 6-18: Application layer protocol specification –
Type 18 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,
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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-
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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
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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
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misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
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between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
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5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
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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
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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.
International Standard IEC 61158-6-18 has been prepared by subcommittee 65C: Industrial
networks, of IEC technical committee 65: Industrial-process measurement, control and
automation.
This second edition cancels and replaces the first edition published in 2007. This edition
constitutes a technical revision.
The main changes with respect to the previous edition are listed below:
• editorial corrections;
• addition of cyclic data segmenting.

– 6 – 61158-6-18 © IEC:2010(E)
The text of this standard is based on the following documents:
FDIS Report on voting
65C/607/FDIS 65C/621/RVD
Full information on the voting for the approval of this 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.
NOTE The revision of this standard will be synchronized with the other parts of the IEC 61158 series.

61158-6-18 © IEC:2010(E) – 7 –
INTRODUCTION
This part of IEC 61158 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/TR 61158-1.
The application protocol provides the application service by making use of the services
available from the data-link or other immediately lower layer. The primary aim of this standard
is to provide a set of rules for communication expressed in terms of the procedures to be
carried out by peer application entities (AEs) at the time of communication. These rules for
communication are intended to provide a sound basis for development in order to serve a
variety of purposes:
• as a guide for implementers and designers;
• for use in the testing and procurement of equipment;
• as part of an agreement for the admittance of systems into the open systems environment;
• as a refinement to the understanding of time-critical communications within OSI.
This standard is concerned, in particular, with the communication and interworking of sensors,
effectors and other automation devices. By using this standard together with other standards
positioned within the OSI or fieldbus reference models, otherwise incompatible systems may
work together in any combination.
NOTE Use of some of the associated protocol types is restricted by their 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 particular data-link layer protocol type to be used with physical layer and application layer protocols in Type
combinations as specified explicitly in the profile parts. Use of the various protocol types in other combinations
may require permission from their respective intellectual-property-right holders.
The International Electrotechnical Commission (IEC) draws attention to the fact that it is
claimed that compliance with this document may involve the use of patents concerning Type
18 elements and possibly other types given in subclause 4. 5, 5.5, 6.9.2 and 9.2.2 as follows:
3343036/Japan [MEC] “Network System for a Programmable Controller”
5896509/USA [MEC] “Network System for a Programmable Controller”
246906/Korea [MEC] “Network System for a Programmable Controller”
19650753/Germany [MEC] “Network System for a Programmable Controller”

IEC takes no position concerning the evidence, validity and scope of these patent rights.
The holder of these patent rights has assured the IEC that he/she is willing to negotiate
licences either free of charge or under reasonable and non-discriminatory terms and
conditions with applicants throughout the world. In this respect, the statement of the holder of
these patent rights is registered with IEC. Information may be obtained from:
[MEC] Mitsubishi Electric Corporation
Corporate Licensing Division
7-3, Marunouchi 2-chome, Chiyoda-ku,
Tokyo 100-8310, Japan
Attention is drawn to the possibility that some of the elements of this document may be the
subject of patent rights other than those identified above. IEC shall not be held responsible for
identifying any or all such patent rights.
ISO (www.iso.org/patents) and IEC (http://www.iec.ch/tctools/patent_decl.htm) maintain on-
line data bases of patents relevant to their standards. Users are encouraged to consult the
data bases for the most up to date information concerning patents.

– 8 – 61158-6-18 © IEC:2010(E)
INDUSTRIAL COMMUNICATION NETWORKS –
FIELDBUS SPECIFICATIONS –
Part 6-18: Application layer protocol specification –
Type 18 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 standard 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 18 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 standard specifies interactions between remote applications and defines the externally
visible behavior provided by the Type 18 fieldbus application layer in terms of
a) the formal abstract syntax defining the application layer protocol data units conveyed
between communicating application entities;
b) the transfer syntax defining encoding rules that are applied to the application layer
protocol data units;
c) the application context state machine defining the application service behavior visible
between communicating application entities;
d) the application relationship state machines defining the communication behavior visible
between communicating application entities.
The purpose of this standard is to define the protocol provided to
a) define the wire-representation of the service primitives defined in IEC 61158-5-18, and
b) define the externally visible behavior associated with their transfer.
This standard specifies the protocol of the Type 18 fieldbus application layer, in conformance
with the OSI Basic Reference Model (ISO/IEC 7498-1) and the OSI application layer structure
(ISO/IEC 9545).
1.2 Specifications
The principal objective of this standard is to specify the syntax and behavior of the application
layer protocol that conveys the application layer services defined in IEC 61158-5-18.
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
protocols standardized in the IEC 61158-6 series.

61158-6-18 © IEC:2010(E) – 9 –
1.3 Conformance
This standard does not specify individual implementations or products, nor do they constrain
the implementations of application layer entities within industrial automation systems.
Conformance is achieved through implementation of this application layer protocol
specification.
2 Normative references
The following referenced documents are indispensable for the application 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.
IEC 61158-5-18:2010 , Industrial communication networks – Fieldbus specifications – Part
5-18: Application layer service definition – Type 18 elements
ISO/IEC 10731, Information technology – Open Systems Interconnection – Basic Reference
Model – Conventions for the definition of OSI services
ISO/IEC 7498-1, Information technology – Open Systems Interconnection – Basic Reference
Model: The Basic Model
ISO/IEC 8822, Information technology – Open Systems Interconnection – Presentation
service definition
ISO/IEC 8824-1, Information technology – Abstract Syntax Notation One (ASN.1):
Specification of basic notation
ISO/IEC 9545, Information technology – Open Systems Interconnection – Application Layer
structure
3 Terms and definitions
3.1 Terms and definitions from other ISO/IEC standards
3.1.1 ISO/IEC 7498-1 terms
For the purposes of this document, the following terms as defined in ISO/IEC 7498-1 apply:
a) application entity
b) application process
c) application protocol data unit
d) application service element
e) application entity invocation
f) application process invocation
g) application transaction
h) real open system
i) transfer syntax
3.1.2 ISO/IEC 8822 terms
For the purposes of this document, the following terms as defined in ISO/IEC 8822 apply:
———————
o be published.
– 10 – 61158-6-18 © IEC:2010(E)
a) abstract syntax
b) presentation context
3.1.3 ISO/IEC 9545 terms
For the purposes of this document, the following terms as defined in ISO/IEC 9545 apply:
a) application-association
b) application-context
c) application context name
d) application-entity-invocation
e) application-entity-type
f) application-process-invocation
g) application-process-type
h) application-service-element
i) application control service element
3.1.4 ISO/IEC 8824-1 terms
For the purposes of this document, the following terms as defined in ISO/IEC 8824-1 apply:
a) object identifier
b) type
3.2 Other terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.2.1
alarm
activation of an event that shows a critical state
3.2.2
alarm ack
acknowledgment of an event that shows a critical state
3.2.3
application
function or data structure for which data is consumed or produced
3.2.4
application layer interoperability
capability of application entities to perform coordinated and cooperative operations using the
services of the FAL
3.2.5
application objects
multiple object classes that manage and provide a run time exchange of PDUs across the
network and within the network device
3.2.6
application process
part of a distributed application on a network, which is located on one device and
unambiguously addressed
61158-6-18 © IEC:2010(E) – 11 –
3.2.7
application process identifier
distinguishes multiple application processes used in a device
NOTE Application process identifier is assigned by PROFIBUS International (PI).
3.2.8
application process object
component of an application process that is identifiable and accessible through an FAL
application relationship
NOTE Application process object definitions are composed of a set of values for the attributes of their class (see
the definition for Application Process Object Class Definition). Application process object definitions may be
accessed remotely using the services of the FAL Object Management ASE. FAL Object Management services can
be used to load or update object definitions, to read object definitions, and to dynamically create and delete
application objects and their corresponding definitions.
3.2.9
application process object class
a class of application process objects defined in terms of the set of their network-accessible
attributes and services
3.2.10
application relationship
cooperative association between two or more application-entity-invocations for the purpose of
exchange of information and coordination of their joint operation. This relationship is activated
either by the exchange of application-protocol-data-units or as a result of preconfiguration
activities
3.2.11
application relationship application service element
application-service-element that provides the exclusive means for establishing and
terminating all application relationships
3.2.12
application relationship endpoint
context and behavior of an application relationship as seen and maintained by one of the
application processes involved in the application relationship
NOTE Each application process involved in the application relationship maintains its own application relationship
endpoint.
3.2.13
attribute
description of an externally visible characteristic or feature of an object
NOTE The attributes of an object contain information about variable portions of an object. Typically, they provide
status information or govern the operation of an object. Attributes may also affect the behavior of an object.
Attributes are divided into class attributes and instance attributes.
3.2.14
backup
status of the IO AR, which indicates that it, is in the standby state
3.2.15
behavior
indication of how an object responds to particular events
3.2.16
class
a set of objects, all of which represent the same kind of system component

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NOTE A class is a generalization of an object; a template for defining variables and methods. All objects in a
class are identical in form and behavior, but usually contain different data in their attributes.
3.2.17
class attributes
attribute that is shared by all objects within the same class
3.2.18
class code
unique identifier assigned to each object class
3.2.19
class specific service
service defined by a particular object class to perform a required function which is not
performed by a common service
NOTE A class specific object is unique to the object class which defines it.
3.2.20
clear
status of the IO controller, which indicates that the control algorithm is currently not running
3.2.21
cyclic
repetitive in a regular manner
3.2.22
device
physical hardware connected to the link
NOTE A device may contain more than one node.
3.2.23
device ID
a vendor assigned device type identification
3.2.24
device profile
a collection of device dependent information and functionality providing consistency between
similar devices of the same device type
3.2.25
diagnosis data object
object(s) which contains diagnosis information referenced by device/slot/subslot/index
3.2.26
diagnosis information
all data available at the server for maintenance purposes
3.2.27
endpoint
one of the communicating entities involved in a connection
3.2.28
engineering
abstract term that characterizes the client application or device responsible for configuring an
automation system via interconnecting data items

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3.2.29
error
discrepancy between a computed, observed or measured value or condition and the specified
or theoretically correct value or condition
3.2.30
error class
general grouping for related error definitions and corresponding error codes
3.2.31
error code
identification of a specific type of error within an error class
3.2.32
event
an instance of a change of conditions
3.2.33
frame
denigrated term for DLPDU, unit of data transfer on a link
3.2.34
identification data object
object(s) that contain information about device, module and sub-module manufacturer and
type referenced by device/slot/subslot/index
3.2.35
implicit AR endpoint
AR endpoint that is defined locally within a device without use of the create service
3.2.36
index
address of a record data object within an application process
3.2.37
instance
the actual physical occurrence of an object within a class that identifies one of many objects
within the same object class
3.2.38
instance attributes
attribute that is unique to an object instance and not shared by the object class
3.2.39
instantiated
object that has been created in a device
3.2.40
interface
collection of FAL class attributes and services that represents a specific view on the FAL
class
3.2.41
invocation
act of using a service or other resource of an application process
NOTE Each invocation represents a separate thread of control that may be described by its context. Once the
service completes, or use of the resource is released, the invocation ceases to exist. For service invocations, a

– 14 – 61158-6-18 © IEC:2010(E)
service that has been initiated but not yet completed is referred to as an outstanding service invocation. Also for
service invocations, an Invoke ID may be used to unambiguously identify the service invocation and differentiate it
from other outstanding service invocations.
3.2.42
IO controller
controlling device, which acts as client for several IO devices (field devices)
NOTE This is usually a programmable controller or a distributed control system.
3.2.43
IO data object
object designated to be transferred cyclically for the purpose of processing and referenced by
device/slot/subslot
3.2.44
IO device
field device which acts as server for IO operation
3.2.45
IO supervisor
engineering device which manages commissioning and diagnosis of an IO system
3.2.46
IO system
system composed of all its IO subsystems
NOTE As an example a PLC with more than one IO controller (network interface) controls one IO system
composed of an IO subsystems for each IO controller.
3.2.47
logical device
a certain FAL class that abstracts a software component or a firmware component as an
autonomous self-contained facility of an automation device
3.2.48
member
piece of an attribute that is structured as an element of an array
3.2.49
method
a synonym for an operational service which is provided by the server ASE and
invoked by a client
3.2.50
module
hardware or logical component of a physical device
3.2.51
network
a set of nodes connected by some type of communication medium, including any intervening
repeaters, bridges, routers and lower-layer gateways
3.2.52
object
abstract representation of a particular component within a device, usually 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

61158-6-18 © IEC:2010(E) – 15 –
3.2.53
object specific service
service unique to the object class which defines it
3.2.54
operate
status of the IO controller that indicates that the control algorithm is currently running
3.2.55
peer
role of an AR endpoint in which it is capable of acting as both client and server
3.2.56
physical device
a certain FAL class that abstracts the hardware facilities of an automation device
3.2.57
point-to-point connection
connection that exists between exactly two application objects
3.2.58
primary
status of the IO AR that indicates that it is in the operating state
NOTE Besides a primary IO AR a backup IO AR may exist. In example used for redundancy and dynamic
reconfiguration of IO data.
3.2.59
property
a synonym for ASE attributes which are readable or writeable via operational ASE services
NOTE These services are generally named “get_” or “set_” and correspond
with the IDL keywords “propget” and “propput”.
3.2.60
provider
a) source of a data connection
b) node or source sending data to one or many consumer
3.2.61
Register X
register containing bit-oriented cyclic data of type input data that is transmitted from a slave to
a master
3.2.62
Register Y
register containing bit-oriented cyclic data of type output data that is transmitted from a
master to a slave
3.2.63
Register Wr
register containing word-oriented cyclic data of type input data that is transmitted from a slave
to a master
3.2.64
Register Ww
register containing word-oriented cyclic data of type output data that is transmitted from a
master to a slave
...