EN 61158-6-22:2014

Industrial communication networks - Fieldbus specifications - Part 6-22: Application layer protocol specification - Type 22 elements

IEC 61158-6-22:2014 defines the protocol provided to define the wire-representation of the service primitives defined in IEC 61158-5-22, and define the externally visible behavior associated with their transfer. This standard specifies the protocol of the IEC fieldbus Application Layer, in conformance with the OSI Basic Reference Model (ISO/IEC 7498-1) and the OSI application layer structure (ISO/IEC 9545). This second edition cancels and replaces the first edition published in 2010 and constitutes a technical revision. The main changes are: Adopted revisions dates of cited standards.

Industrielle Kommunikationsnetze - Feldbusse - Teil 6-22: Protokollspezifikation des Application Layer (Anwendungsschicht) - Typ 22-Elemente

Réseaux de communication industriels - Spécifications des bus de terrain - Partie 6-22: Spécification du protocole de la couche application - Éléments de type 22

L'IEC 61158-6-22:2014 décrit le protocole mis en place pour définir la représentation filaire des primitives de service définies dans la CEI 61158-5-22 et définir le comportement visible de l'extérieur associé à leur transfert. La présente norme spécifie le protocole de la couche application de bus de terrain de l'IEC, en conformité avec le modèle de référence de base OSI (ISO/CEI 7498-1) et la structure de la couche application OSI (ISO/CEI 9545). Cette deuxième édition annule et remplace la première édition parue en 2010. Elle constitue une révision technique. Les principales modifications sont: Adoption des dates de révision des normes citées.

Industrijska komunikacijska omrežja - Specifikacije za procesna vodila - 6-22. del: Specifikacija protokola na aplikacijski ravni - Elementi tipa 22 (IEC 61158-6-22:2014)

Namen standarda IEC 61158-6-22:2014 je opredeliti protokol za določitev žične predstavitve primitivov opravil iz standarda IEC 61158-5-22 in določitev zunanje vidnega vedenja, povezanega z njihovim prenosom. Ta standard določa protokol aplikacijskega nivoja procesnih vodil IEC v skladu z osnovnim referenčnim modelom OSI (ISO/IEC 7498-1) in strukturo aplikacijskega nivoja OSI (ISO/IEC 9545). Ta druga izdaja razveljavlja in nadomešča prvo izdajo, objavljeno leta 2010, in predstavlja tehnično popravljeno izdajo. Glavne spremembe so: Datumi sprejetih popravkov navedenih standardov.

General Information

• Status: Published
• Publication Date: 30-Oct-2014
• Withdrawal Date: 22-Sep-2017
• 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: 31-Oct-2014
• Completion Date: 31-Oct-2014
• Mandate: M/490 - Standardisation mandate to the European Standardisation Organisations (ESOs) to support European Smart Grid deployment
• Ref Project: SIST EN 61158-6-22:2015 - Industrial communication networks - Fieldbus specifications - Part 6-22: Application layer protocol specification - Type 22 elements (IEC 61158-6-22:2014)

Relations

• Replaces: EN 61158-6-22:2012 - Industrial communication networks - Fieldbus specifications - Part 6-22: Application layer protocol specification - Type 22 elements
• Effective Date: 04-Nov-2014
• Parent: EN 61158-6-2:2014 - Industrial communication networks - Fieldbus specifications - Part 6-2: Application layer protocol specification - Type 2 elements
• Effective Date: 07-Jun-2022
• Parent: EN 61158-6-2:2014 - Industrial communication networks - Fieldbus specifications - Part 6-2: Application layer protocol specification - Type 2 elements
• Effective Date: 23-Mar-2020

Overview

EN 61158-6-22:2014 (IEC 61158-6-22:2014) is the European/Slovenian adoption of the international standard that specifies the application layer protocol for Type 22 fieldbus elements. The standard defines the wire representation of service primitives (as specified in IEC 61158-5-22) and the externally visible behaviour associated with their transfer. It is aligned with the OSI Basic Reference Model (ISO/IEC 7498-1) and the OSI application layer structure (ISO/IEC 9545). This second edition supersedes the 2010 edition; the main technical change noted is the adoption of revised citation dates for referenced standards.

Key technical topics and requirements

The standard details the structure, encoding and runtime behaviour of the fieldbus application layer. Major technical topics include:

• Application layer protocol specification (FAL): operating principles, application layer structure and device reference models (RTFL, RTFN).
• FAL syntax and data encoding: transfer syntax for bit sequences, integer and unsigned types, and special types such as TimeOfDay and TimeDifference.
• Object dictionary and addressing: object definitions, object types and schema for application objects used by devices.
• Service primitives and CeS encoding: wire-representation of primitives defined in IEC 61158-5-22 and communication section (CeS) encoding rules.
• Protocol state machines: definitions and state machines for the Fieldbus Service Protocol Machine (FSPM), Application Layer State Machine (ALSM), Application Relationship Protocol Machine (ARPM), and DLL mapping protocol machine (DMPM).
• DLL mapping and management: primitives exchanged between ALSM and DMPM, ALSM-to-DLL mapping, management and diagnostic encodings.
• Diagnostics and device configuration: error registers, event logs, manufacturer identity, time sync, SDO/EMCY/PDO parameters and timeouts (as listed in the tables).

The document includes normative references to related parts of IEC 61158 and relevant ISO/IEC standards necessary for conformance and implementation.

Practical applications

This standard is used to:

• Implement the application layer protocol in fieldbus devices and gateways.
• Ensure interoperability between Type 22 fieldbus nodes from different vendors.
• Guide system integrators and automation engineers when configuring application-layer services, diagnostics and object dictionaries.
• Provide a basis for conformance testing and certification of fieldbus products.

Who should use this standard

• Fieldbus device manufacturers and firmware developers
• Control-system and industrial network integrators
• Automation architects and system designers
• Test laboratories and certification bodies ensuring compliance with IEC/CENELEC requirements

Related standards

• IEC 61158-5-22 (Application layer service definition - Type 22)
• IEC 61158-3-22 / 4-22 (Data-link layer service and protocol for Type 22)
• ISO/IEC 7498-1, ISO/IEC 9545 (OSI model and application layer structure)

Keywords: EN 61158-6-22:2014, IEC 61158-6-22, fieldbus, application layer protocol, Type 22, industrial communication networks, OSI model, object dictionary, protocol state machines.

Standards Content (Sample)

SLOVENSKI STANDARD
01-marec-2015
1DGRPHãþD
SIST EN 61158-6-22:2012
Industrijska komunikacijska omrežja - Specifikacije za procesna vodila - 6-22. del:
Specifikacija protokola na aplikacijski ravni - Elementi tipa 22 (IEC 61158-6-
22:2014)
Industrial communication networks - Fieldbus specifications - Part 6-22: Application layer
protocol specification - Type 22 elements (IEC 61158-6-22:2014)
Industrielle Kommunikationsnetze - Feldbusse - Teil 6-22: Protokollspezifikation des
Application Layer (Anwendungsschicht) - Typ 22-Elemente (IEC 61158-6-22:2014)
Réseaux de communication industriels - Spécifications des bus de terrain - Partie 6-22:
Spécification du protocole de la couche application - Éléments de type 22 (CEI 61158-6-
22:2014)
Ta slovenski standard je istoveten z: EN 61158-6-22:2014
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 61158-6-22

NORME EUROPÉENNE
EUROPÄISCHE NORM
October 2014
ICS 25.040.40; 35.100.70; 35.110 Supersedes EN 61158-6-22:2012
English Version
Industrial communication networks - Fieldbus specifications -
Part 6-22: Application layer protocol specification - Type 22
elements
(IEC 61158-6-22:2014)
Réseaux de communication industriels - Spécifications des Industrielle Kommunikationsnetze - Feldbusse - Teil 6-22:
bus de terrain - Partie 6-22: Spécification du protocole de la Protokollspezifikation des Application Layer
couche application - Éléments de type 22 (Anwendungsschicht) - Typ 22-Elemente
(CEI 61158-6-22:2014) (IEC 61158-6-22:2014)
This European Standard was approved by CENELEC on 2014-09-23. 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, Former Yugoslav Republic of Macedonia, 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.

European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2014 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN 61158-6-22:2014 E
Foreword
The text of document 65C/764/FDIS, future edition 2 of IEC 61158-6-22, 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 61158-6-22:2014.
The following dates are fixed:
(dop) 2015-06-23
• latest date by which the document has to be implemented at
national level by publication of an identical national
standard or by endorsement
(dow) 2017-09-23
• latest date by which the national standards conflicting with
the document have to be withdrawn

This document supersedes EN 61158-6-22:2012.
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.
This document has been prepared under a mandate given to CENELEC by the European Commission
and the European Free Trade Association.
Endorsement notice
The text of the International Standard IEC 61158-6-22:2014 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 61158-1 NOTE Harmonized as EN 61158-1.
IEC 61784-1 NOTE Harmonized as EN 61784-1.
IEC 61784-2 NOTE Harmonized as EN 61784-2.

- 3 - EN 61158-6-22:2014
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 1 When 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 61158-3-22 -  Industrial communication networks - EN 61158-3-22 -
Fieldbus specifications -
Part 3-22: Data-link layer service
definition - Type 22 elements
IEC 61158-4-22 -  Industrial communication networks - EN 61158-4-22 -
Fieldbus specifications -
Part 4-22: Data-link layer protocol
specification - Type 22 elements
IEC 61158-5-22 -  Industrial communication networks - EN 61158-5-22 -
Fieldbus specifications -
Part 5-22: Application layer service
definition - Type 22 elements
ISO/IEC 7498-1 -  Information technology - Open Systems - -
Interconnection - Basic reference model:
The basic model
ISO/IEC 8802-3 -  Information technology - - -
Telecommunications and information
exchange between systems - Local and
metropolitan area networks - Specific
requirements -
Part 3: Carrier sense multiple access with
collision detection (CSMA/CD) access
method and physical layer specifications
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
Publication Year Title EN/HD Year
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

IEC 61158-6-22 ®
Edition 2.0 2014-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Industrial communication networks – Fieldbus specifications –

Part 6-22: Application layer protocol specification – Type 22 elements

Réseaux de communication industriels – Spécifications des bus de terrain –

Partie 6-22: Spécification du protocole de la couche application – Éléments

de type 22
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX XD
ICS 25.040.40; 35.100.70; 35.110 ISBN 978-2-8322-1767-2

– 2 – IEC 61158-6-22:2014 © IEC 2014
CONTENTS
FOREWORD . 6
INTRODUCTION . 8
1 Scope . 9
1.1 General . 9
1.2 Specifications . 10
1.3 Conformance . 10
2 Normative references . 10
3 Terms, definitions, abbreviations, symbols and conventions . 11
3.1 Terms and definitions from other ISO/IEC standards . 11
3.2 Fieldbus application-layer specific definitions . 11
3.3 Abbreviations and symbols . 15
3.4 Conventions . 17
4 Application layer protocol specification . 18
4.1 Operating principle . 18
4.2 Device reference models . 19
4.3 Application layer structure . 21
5 FAL syntax description . 21
5.1 Introduction and coding principles . 21
5.2 Data type encoding . 21
5.3 CeS encoding . 25
5.4 ISO/IEC 8802-3 DLPDU communication inside Type 22 RTFL . 71
5.5 Management encoding . 71
6 FAL protocol state machines . 72
6.1 Overview . 72
6.2 Fieldbus service protocol machine (FSPM) . 74
6.3 Application relationship protocol machine (ARPM) . 74
6.4 DLL mapping protocol machine . 74
7 AP-context state machine . 74
8 FAL service protocol machine (FSPM) . 74
9 Application layer state machine (ALSM) . 75
9.1 Description . 75
9.2 States . 77
9.3 Primitive definitions . 77
9.4 State table . 78
9.5 AL-service forwarding depending on AL-state . 79
10 DLL mapping protocol machine (DMPM) . 80
10.1 Overview . 80
10.2 Primitives exchanged between ALSM and DMPM . 80
10.3 Primitives exchanged between DLL and DMPM . 84
10.4 ALSM to DLL mapping . 86
Bibliography . 87

Figure 1 – RTFL device reference model . 20
Figure 2 – RTFN device reference model . 21
Figure 3 – Encoding of TimeOfDay value . 22

IEC 61158-6-22:2014 © IEC 2014 – 3 –
Figure 4 – Encoding of TimeDifference value . 23
Figure 5 – Object dictionary addressing schema . 26
Figure 6 – Relationships among protocol machines and adjacent layers . 73
Figure 7 – ALSM protocol machine . 74
Figure 8 – ALSM diagram . 76

Table 1 – PDU element definition . 18
Table 2 – Object definition . 18
Table 3 – Transfer syntax for bit sequences . 22
Table 4 – Transfer syntax for Integer data type . 24
Table 5 – Transfer syntax for Unsigned data type . 24
Table 6 – Object dictionary structure . 25
Table 7 – Object dictionary object type definitions . 26
Table 8 – Basic data type definitions . 26
Table 9 – Complex data type definition . 27
Table 10 – Communication section . 28
Table 11 – Device type . 30
Table 12 – Error register encoding . 30
Table 13 – Error register . 31
Table 14 – Object definition template . 31
Table 15 – Encoding of event log entries . 32
Table 16 – Event log . 32
Table 17 – Manufacturer device name . 33
Table 18 – Manufacturer HW version . 33
Table 19 – Manufacturer SW version . 33
Table 20 – CL configuration . 34
Table 21 – Time sync IRQ configuration encoding . 36
Table 22 – Time sync IRQ configuration . 36
Table 23 – Time sync IRQ state . 36
Table 24 – Store parameters read information . 37
Table 25 – Store parameters. 37
Table 26 – Restore parameters read information . 39
Table 27 – Restore default parameters . 39
Table 28 – Diagnostic information . 40
Table 29 – Diagnostic threshold . 43
Table 30 – IP address EMCY . 45
Table 31 – Inhibit time EMCY. 45
Table 32 – Encoding of consumer heartbeat entries . 45
Table 33 – Consumer heartbeat list . 46
Table 34 – Producer heartbeat parameter . 47
Table 35 – Identity object . 49
Table 36 – SDO protocol timeout . 50
Table 37 – Enable client SDO parameter . 50

– 4 – IEC 61158-6-22:2014 © IEC 2014
Table 38 – Enable EMCY . 51
Table 39 – PDO timeout tolerance . 51
Table 40 – Store EDS . 52
Table 41 – Storage format . 52
Table 42 – OS command . 52
Table 43 – OS command mode . 53
Table 44 – OS debugger interface . 54
Table 45 – OS prompt . 55
Table 46 – Module list . 56
Table 47 – Emergency subscriber encoding . 57
Table 48 – Emergency subscriber . 57
Table 49 – Client SDO parameter encoding . 57
Table 50 – Client SDO parameter . 58
Table 51 – Receive PDO communication parameter . 58
Table 52 – Transmit PDO communication parameter . 60
Table 53 – Mapping format . 63
Table 54 – Receive PDO mapping parameter. 63
Table 55 – Transmit PDO mapping parameter . 64
Table 56 – Initiate SDO expedited download request . 64
Table 57 – Initiate SDO expedited download response . 65
Table 58 – Initiate SDO normal download request . 65
Table 59 – Initiate SDO normal download response . 65
Table 60 – SDO download request . 65
Table 61 – SDO download response . 66
Table 62 – Initiate SDO expedited upload request . 66
Table 63 – Initiate SDO expedited upload response . 66
Table 64 – Initiate SDO normal upload response . 67
Table 65 – SDO upload request . 67
Table 66 – SDO upload response . 67
Table 67 – SDO abort request . 67
Table 68 – SDO abort codes . 68
Table 69 – Process data write request via MSC . 69
Table 70 – Process data write request via CDC . 69
Table 71 – Emergency request . 69
Table 72 – Emergency error codes . 69
Table 73 – Heartbeat request via MSC . 70
Table 74 – Heartbeat request via CDC . 71
Table 75 – Send frame request . 71
Table 76 – Application layer management request . 72
Table 77 – State transitions and management services . 76
Table 78 – Primitives issued by ALSM to DLL . 78
Table 79 – Primitives issued by DLL to ALSM . 78
Table 80 – Primitives issued by FSPM to ALSM . 78

IEC 61158-6-22:2014 © IEC 2014 – 5 –
Table 81 – Primitives issued by ALSM to FSPM . 78
Table 82 – ALSM state table . 79
Table 83 – Application layer states and communication services. 79
Table 84 – Primitives issued by ALSM to DMPM . 80
Table 85 – Primitives issued by DMPM to ALSM . 82
Table 86 – Primitives issued by DMPM to DLL . 84
Table 87 – Primitives issued by DLL to DMPM . 85
Table 88 – ALSM to DLL mapping . 86

– 6 – IEC 61158-6-22:2014 © IEC 2014
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
INDUSTRIAL COMMUNICATION NETWORKS –
FIELDBUS SPECIFICATIONS –
Part 6-22: Application layer protocol specification –
Type 22 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 61158-6-22 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 2010. This edition
constitutes a technical revision.

IEC 61158-6-22:2014 © IEC 2014 – 7 –
This edition includes the following technical changes with respect to the previous edition.
• Adopted revisions dates of cited standards.
The text of this standard is based on the following documents:
FDIS Report on voting
65C/764/FDIS 65C/774/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.
– 8 – IEC 61158-6-22:2014 © IEC 2014
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 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 implementors 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.

IEC 61158-6-22:2014 © IEC 2014 – 9 –
INDUSTRIAL COMMUNICATION NETWORKS –
FIELDBUS SPECIFICATIONS –
Part 6-22: Application layer protocol specification –
Type 22 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 22 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 defines in an abstract way the externally visible behavior provided by the
different Types of the fieldbus Application Layer in terms of:
a) the abstract syntax defining the application layer protocol data units conveyed between
communicating application entities;
b) the transfer syntax defining the application layer protocol data units conveyed between
communicating application entities;
c) the application context state machine defining the application service behavior visible
between communicating application entities; and
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 61158-5-22; and
b) define the externally visible behavior associated with their transfer.
This standard specifies the protocol of the IEC fieldbus Application Layer, in conformance
with the OSI Basic Reference Model (ISO/IEC 7498-1) 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

– 10 – IEC 61158-6-22:2014 © IEC 2014
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 standard to provide access to the FAL to control certain aspects of its operation.
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 61158-5-22.
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 subparts of IEC 61158-6.
1.3 Conformance
This standard 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 the application layer service definition standard.
Instead, conformance is achieved through implementation of this application layer protocol
specification.
2 Normative references
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 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 61158-3-22, Industrial communication networks – Fieldbus specifications –
Part 3-22: Data-link layer service definition – Type 22 elements
IEC 61158-4-22, Industrial communication networks – Fieldbus specifications –
Part 4-22: Data-link layer protocol specification – Type 22 elements
IEC 61158-5-22, Industrial communication networks – Fieldbus specifications –
Part 5-22: Application layer service definition – Type 22 elements
ISO/IEC 7498-1, Information technology – Open Systems Interconnection – Basic Reference
Model: The Basic Model
ISO/IEC 8802-3, Information technology – Telecommunications and information exchange
between systems – Local and metropolitan area networks – Specific requirements – Part 3:
Carrier sense multiple access with collision detection (CSMA/CD) access method and
physical layer specifications
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
IEC 61158-6-22:2014 © IEC 2014 – 11 –
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
3 Terms, definitions, abbreviations, symbols and conventions
For the purposes of this document, the following terms, definitions, symbols, abbreviations
and conventions apply:
3.1 Terms and definitions from other ISO/IEC standards
3.1.1 ISO/IEC 7498-1 terms
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
a) abstract syntax
b) presentation context
3.1.3 ISO/IEC 9545 terms
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
a) object identifier
b) type
3.2 Fieldbus application-layer specific definitions
3.2.1
acyclic data
data which is transferred from time to time for dedicated purposes

– 12 – IEC 61158-6-22:2014 © IEC 2014
3.2.2
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.
3.2.3
cell
synonym for a single DL-segment which uses RTFL communication model
3.2.4
channel
path provided for conveying data
3.2.5
client
object which uses the services of a server by initiating a message to perform a task
3.2.6
communication cycle
fixed time period between which the root device issues empty frames for cyclic
communication initiation in which data is transmitted utilizing CDC and MSC
3.2.7
connection
logical binding between two application objects
3.2.8
cycle time
duration of a communication cycle
3.2.9
cyclic
events which repeat in a regular and repetitive manner
3.2.10
cyclic communication
periodic exchange of telegrams
3.2.11
cyclic data
data which is transferred in a regular and repetitive manner for dedicated purposes
3.2.12
cyclic data channel
CDC
part of one or more frames, which is reserved for cyclic data
3.2.13
data
generic term used to refer to any information carried over a fieldbus
3.2.14
device
physical entity connected to the fieldbus

IEC 61158-6-22:2014 © IEC 2014 – 13 –
3.2.15
error
discrepancy between a computed, observed or measured value or condition and the specified
or theoretically correct value or condition
3.2.16
error code
identification number of a specific type of error
3.2.17
gateway
device acting as a linking element between different protocols
3.2.18
index
position of an object within the object dictionary
3.2.19
inter-cell communication
communication between a RTFL device and a RTFN device or communication between a
RTFL device and another RTFL device in different cells linked by RTFN
3.2.20
interface
shared boundary between two functional units, defined by functional characteristics, signal
characteristic, or other characteristics as appropriate
3.2.21
intra-cell communication
communication between a RTFL device and another RTFL device in the same cell
3.2.22
logical double line
sequence of root device and all ordinary devices processing the communication frame in
forward and backward direction
3.2.23
mapping parameters
set of values defining the correspondence between application objects and process data
objects
3.2.24
master clock
global time base for the PCS mechanism
3.2.25
message
ordered sequence of octets intended to convey data
3.2.26
message channel
MSC
part of one or more frames, which is reserved for acyclic data
3.2.27
network
set of devices connected by some type of communication medium, including any intervening
repeaters, bridges, routers and lower-layer gateways

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3.2.28
ordinary device
OD
slave in the communication system, which utilizes RTFL for cyclic and acyclic data
interchange with other ODs in the same logical double line
3.2.29
precise clock synchronization
PCS
mechanism to synchronize clocks of RTFL devices and maintain a global time base
3.2.30
process data
data designated to be transferred cyclically or acyclically for the purpose of processing
3.2.31
process data object
dedicated data object(s) designated to be transferred cyclically or acyclically for the purpose
of processing
3.2.32
protocol
convention about the data formats, time sequences, and error correction in the data exchange
of communication systems
3.2.33
root device
RD
master in the communication system, which organises, initiates and controls the RTFL cyclic
and acyclic data interchange for one logical double line
3.2.34
real time frame line
RTFL
communication model communicating in a logical double line
3.2.35
real time frame network
RTFN
communication model communicating in a switched network
3.2.36
round trip time
transmission time needed by a DLPDU from the RD to the last OD in forward and backward
direction
3.2.37
sub-index
sub-position of an individual element of an object within the object dictionary
3.2.38
timing signal
time-based indication of the occurrence of an event
...