IEC 61158-5-12:2014

Industrial communication networks - Fieldbus specifications - Part 5-12: Application layer service definition - Type 12 elements

IEC 61158-5-12:2014 defines the services provided to the FAL user at the boundary between the user and the application layer of the fieldbus reference model, and Systems Management at the boundary between the application layer and Systems Management of the fieldbus reference model. This standard specifies the structure and services 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 third edition cancels and replaces the second edition published in 2010 and constitutes a technical revision. The main changes are:
- bug fixes;
- editorial improvements;
- support of Explicit Device Identification added in ESM.

Réseaux de communication industriels - Spécifications des bus de terrain - Partie 5-12: Définition des services de la couche application - Eléments de type 12

L'IEC 61158-5-12:2014 défini les services mis en place pour l'utilisateur de FAL, à la frontière entre l'utilisateur et la couche application du modèle de référence de bus de terrain; et la Gestion des systèmes, à la frontière entre la couche application et la Gestion des systèmes selon le modèle de référence de bus de terrain. La présente norme spécifie la structure et les services de la couche application de bus de terrain IEC, en conformité avec le modèle de référence de base de l'OSI (ISO/CEI 7498-1) et la structure de la couche application de l'OSI (ISO/CEI 9545). Cette troisième édition annule et remplace la deuxième édition parue en 2010. Elle constitue une révision technique. Cette édition inclut les modifications majeures suivantes:
- réparations des erreurs;
- améliorations éditoriales;
- prise en charge de l'Identification Explicite d'Appareils ajoutée dans l'ESM.

General Information

• Status: Published
• Publication Date: 17-Aug-2014
• ICS: 25.040.40 - Industrial process measurement and control
• ICS: 29.140.40 - Luminaires
• ICS: 35.100.70 - Application layer
• ICS: 35.110 - Networking
• Technical Committee: SC 65C - Industrial networks
• Current Stage: DELPUB - Deleted Publication
• Start Date: 10-Apr-2019
• Completion Date: 26-Oct-2025

Relations

• Revises: IEC 61158-5-12:2010 - Industrial communication networks - Fieldbus specifications - Part 5-12: Application layer service definition - Type 12 elements
• Effective Date: 05-Sep-2023
• Revised: IEC 61158-5-12:2019 - Industrial communication networks - Fieldbus specifications - Part 5-12: Application layer service definition - Type 12 elements
• Effective Date: 05-Sep-2023

Overview

IEC 61158-5-12:2014 is an international standard developed by the International Electrotechnical Commission (IEC) focusing on industrial communication networks, specifically Fieldbus specifications. This part, 5-12, defines the Application Layer Service Definition for Type 12 elements. It establishes comprehensive guidelines and service definitions provided to the Fieldbus Application Layer (FAL) user, specifically at the interface between the user and the application layer within the fieldbus reference model.

This third edition represents a technical revision over the earlier 2010 version, featuring important bug fixes, editorial improvements, and the introduction of Explicit Device Identification support in the Embedded Systems Management (ESM). The standard aligns with the OSI Basic Reference Model (ISO/IEC 7498-1) and the OSI application layer structure (ISO/IEC 9545), ensuring compatibility with widely accepted communication frameworks.

Key Topics

• Application Layer Service Definition
  Defines services accessible to the application layer user and systems management, which includes data exchange, device control, and diagnostic interactions within industrial processes.

• Conformance to OSI Models
  Provides structure and services consistent with OSI Reference Model, enhancing interoperability and standardized communication within fieldbus networks.

• Type 12 Elements Specification
  Details the data types, communication model, and service primitives specific to Type 12 application layer elements.

• Systems Management Services
  Integrates application layer functions with systems management through ESM, including the newly added Explicit Device Identification, facilitating network device management.

• Bug Fixes and Editorial Improvements
  Ensures enhanced clarity, consistency, and performance of the standard through the latest revisions.

Applications

IEC 61158-5-12:2014 serves as an essential standard for manufacturers, system integrators, and end-users involved in:

• Industrial Automation Systems
  Ensuring reliable communication between control systems and field devices for processes like manufacturing, energy production, and process control.

• Fieldbus Network Design and Implementation
  Structuring communication layers to promote interoperability and seamless data exchange in complex industrial environments.

• Device and System Management
  Enhancing device identification, diagnostics, and control within fieldbus networks for improved maintenance and network reliability.

• Integration with Higher-Level Systems
  Providing standardized application layer services that interface effectively with supervisory control and data acquisition (SCADA) and enterprise-level systems.

Related Standards

• IEC 61158 Fieldbus Series
  The broader IEC 61158 series covers various types and parts of fieldbus communication networks, including lower layers like the data link and physical layers.

• ISO/IEC 7498-1
  OSI Basic Reference Model standard, providing architecture context for layered communication protocols.

• ISO/IEC 9545
  OSI Application Layer structure standard that IEC 61158-5-12 aligns with for application layer service definitions.

• IEC 61784
  Standards for fieldbus profiles that complement IEC 61158 specifications for interoperability between products.

• IEC 61131
  Focuses on programmable controllers and can work alongside IEC 61158 for automation system integration.

By adhering to IEC 61158-5-12:2014, stakeholders in the industrial communication domain ensure robust, interoperable application layer services that support efficient and reliable fieldbus network operations across diverse industrial sectors.

Standards Content (Sample)

IEC 61158-5-12 ®
Edition 3.0 2014-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Industrial communication networks – Fieldbus specifications –
Part 5-12: Application layer service definition – Type 12 elements

Réseaux de communication industriels – Spécifications des bus de terrain –
Partie 5-12: Définition des services de la couche application – Éléments
de type 12
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IEC 61158-5-12 ®
Edition 3.0 2014-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Industrial communication networks – Fieldbus specifications –

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

Réseaux de communication industriels – Spécifications des bus de terrain –

Partie 5-12: Définition des services de la couche application – Éléments

de type 12
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
XF
CODE PRIX
ICS 25.040.40; 35.100.70; 35.110 ISBN 978-2-8322-1737-5

– 2 – IEC 61158-5-12:2014 © IEC 2014

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
5 Data type ASE . 26
5.1 General . 26
5.2 Formal definition of data type objects . 26
5.3 FAL defined data types . 26
5.4 Data type ASE service specification . 35
6 Communication model specification . 35
6.1 ASEs . 35
6.2 AR . 116
Bibliography . 129

Figure 1 – Producer consumer model . 19
Figure 2 – Client server model . 19
Figure 3 – Server triggered invocation . 19
Figure 4 – Slave reference model . 21

Figure 5 – Simple slave device . 22
Figure 6 – Complex slave device . 23
Figure 7 – Master functional overview . 24
Figure 8 – Process output data sequence . 36
Figure 9 – Process input data sequence . 37
Figure 10 – CoE server model . 55
Figure 11 – Successful single SDO-Download sequence. 60
Figure 12 – Unsuccessful single SDO-Download sequence . 61
Figure 13 – Successful segmented SDO-Download sequence . 62
Figure 14 – Successful single SDO-Upload sequence . 63
Figure 15 – Unsuccessful single SDO-Upload sequence . 64
Figure 16 – Successful segmented SDO-Upload sequence . 65

Figure 17 – SDO information sequence . 66

Figure 18 – Emergency service . 67

Figure 19 – Command sequence . 68

Figure 20 – PDO mapping . 70

Figure 21 – Sync manager PDO assigment . 71

Figure 22 – RxPDO service . 73

Figure 23 – TxPDO service . 74

Figure 24 – RxPDO remote transmission sequence . 75

Figure 25 – TxPDO remote transmission sequence . 76
Figure 26 – EoE sequence . 96
Figure 27 – FoE read sequence with success . 104
Figure 28 – FoE read sequence with error . 105
Figure 29 – FoE write sequence with success . 106
Figure 30 – FoE write sequence with error. 107
Figure 31 – FoE write sequence with busy . 108
Figure 32 – Successful AL control sequence . 118
Figure 33 – Unsuccessful AL control sequence . 119
Figure 34 – AL state changed sequence . 120

Table 1 – Process output data . 39
Table 2 – Process input data . 40
Table 3 – Update process input data . 41
Table 4 – SII read . 49
Table 5 – SII write . 50
Table 6 – SII reload . 51
Table 7 – Allocation of SDO areas. 55
Table 8 – SDO download expedited . 80
Table 9 – SDO download normal . 81
Table 10 – Download SDO segment . 82
Table 11 – SDO upload expedited . 83
Table 12 – SDO upload normal . 84

Table 13 – Upload SDO segment . 85
Table 14 – Abort SDO transfer . 85
Table 15 – Get OD list . 86
Table 16 – OD list segment . 87
Table 17 – Get object description . 88
Table 18 – Get entry description . 89
Table 19 – Object entry segment . 91
Table 20 – Emergency . 92
Table 21 – RxPDO . 93
Table 22 – TxPDO . 93
Table 23 – RxPDO remote transmission . 94
Table 24 – TxPDO remote transmission . 94

– 4 – IEC 61158-5-12:2014 © IEC 2014

Table 25 – Initiate EoE. 99

Table 26 – EoE fragment . 100

Table 27 – Set IP parameter . 101

Table 28 – Set address filter . 102

Table 29 – FoE read . 109

Table 30 – FoE write . 110

Table 31 – FoE data . 110

Table 32 – FoE ack . 111

Table 33 – FoE busy . 111
Table 34 – FoE error . 112
Table 35 – MBX read . 113
Table 36 – MBX write . 114
Table 37 – MBX read upd . 115
Table 38 – AL management and ESM service primitives . 117
Table 39 – AL control . 127
Table 40 – AL state change . 128

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
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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
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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
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6) All users should ensure that they have the latest edition of this publication.
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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 third edition cancels and replaces the second edition published in 2010. This edition
constitutes a technical revision. The main changes with respect to the previous edition are
listed below:
– 6 – IEC 61158-5-12:2014 © IEC 2014

• bug fixes;
• editorial improvements;
• support of Explicit Device Identification added in ESM (see 6.2.2)

The text of this standard is based on the following documents:

FDIS Report on voting
65C/763/FDIS 65C/773/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.
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 service is provided by the application protocol making use of the services

available from the data-link or other immediately lower layer. This standard 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 standard is a conceptual architectural
service, independent of administrative and implementation divisions.

– 8 – IEC 61158-5-12:2014 © IEC 2014

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 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 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 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 standard 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 standard 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

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 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 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 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 standard.
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 61131-3, Programmable controllers – Part 3: Programming languages
IEC 61158-1:2014, Industrial communication networks – Fieldbus specifications – Part 1:
Overview and guidance for the IEC 61158 and IEC 61784 series
IEC 61158-3-12, 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 61158-5-12:2014 © IEC 2014

ISO/IEC 7498-3, Information technology – Open Systems Interconnection – Basic Reference

Model: Naming and addressing
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 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; available at
IETF RFC 791, Internet Protocol darpa internet program protocol specification; available at

3 Terms, definitions, symbols, abbreviations and conventions
For the purposes of this document, the following terms, definitions, symbols, abbreviations
and conventions apply.
3.1 Reference model terms and definitions
This standard 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]
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 standard 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]
3.3.3
basic slave
slave device that supports only physical addressing of data

– 12 – IEC 61158-5-12:2014 © IEC 2014

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
1) object which uses the services of another (server) object to perform a task

2) initiator of a message to which a server reacts

3.3.6
communication object
component that manage and provide a run time exchange of messages across the network
3.3.7
connection
logical binding between two application objects within the same or different devices
3.3.8
cyclic
events which repeat in a regular and repetitive manner
3.3.9
data
generic term used to refer to any information carried over a fieldbus
3.3.10
data consistency
means for coherent transmission and access of the input- or output-data object between and
within client and server
3.3.11
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.
3.3.12
data type object
entry in the object dictionary indicating a data type

3.3.13
default gateway
device with at least two interfaces in two different IP subnets acting as router for a subnet.
3.3.14
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.)
3.3.15
device profile
collection of device dependent information and functionality providing consistency between
similar devices of the same device

3.3.16
diagnosis information
all data available at the server for maintenance purposes

3.3.17
distributed clocks
method to synchronize slaves and maintain a global time base

3.3.18
error
discrepancy between a computed, observed or measured value or condition and the specified

or theoretically correct value or condition
3.3.19
error class
general grouping for related error definitions and corresponding error codes
3.3.20
error code
identification of a specific type of error within an error class
3.3.21
event
instance of a change of conditions
3.3.22
fieldbus memory management unit
function that establishes one or several correspondences between logical addresses and
physical memory
3.3.23
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
3.3.24
frame
denigrated synonym for DLPDU
3.3.25
full slave
slave device that supports both physical and logical addressing of data
3.3.26
index
address of an object within an application process
3.3.27
interface
shared boundary between two functional units, defined by functional characteristics, signal
characteristics, or other characteristics as appropriate
3.3.28
little endian
method for data representation of numbers greater 8 bit where the least significant octet is
transmitted first
– 14 – IEC 61158-5-12:2014 © IEC 2014

3.3.29
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

3.3.30
mapping
correspondence between two objects in that way that one object is part of the other object

3.3.31
mapping parameters
set of values defining the correspondence between application objects and process data
objects
3.3.32
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.
3.3.33
message
ordered series of octets intended to convey information
Note 1 to entry: Normally used to convey information between peers at the application layer.
3.3.34
network
set of nodes connected by some type of communication medium, including any intervening
repeaters, bridges, routers and lower-layer gateways
3.3.35
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
[Derived from IEC 61158-2]
3.3.36
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.
3.3.37
object dictionary
data structure addressed by Index and Sub-index that contains descriptions of data type
objects, communication objects and application objects

3.3.38
process data
collection of application objects designated to be transferred cyclically or acyclically for the

purpose of measurement and control

3.3.39
process data object
structure described by mapping parameters containing one or several process data entities

3.3.40
segment
collection of one real master with one or more slaves
3.3.41
server
object which provides services to another (client) object
3.3.42
service
operation or function that an object and/or object class performs upon request from another
object and/or object class
3.3.43
slave
DL-entity accessing the medium only after being initiated by the preceding slave or the master
3.3.44
sub-index
subaddress of an object within the object dictionary
3.3.45
Sync Manager
collection of control elements to coordinate access to concurrently used objects.
3.3.46
Sync Manager channel
single control elements to coordinate access to concurrently used objects.
3.3.47
switch
MAC bridge as defined in IEEE 802.1D

3.4 Common symbols and abbreviations
AL- Application layer (as a prefix)
ALE AL-entity (the local active instance of the application layer)
AL AL-layer
APDU AL-protocol-data-unit
ALM AL-management
ALME AL-management Entity (the local active instance of AL-management)
ALMS AL-management service
ALS AL-service
AR Application relationship
ASE Application service element
CAN Controller Area Network
– 16 – IEC 61158-5-12:2014 © IEC 2014

CiA CAN in Automation
CoE CAN appliclication protocol over Type 12 services

CSMA/CD Carrier sense multiple access with collision detection

DC Distributed clocks
DL Data-link-layer
DNS Domain name system (server for name resolution in IP networks)

E²PROM Electrically erasable programmable read only memory

EoE Ethernet tunneled over Type 12 services

ESC Type 12 slave controller
FCS Frame check sequence
FIFO First-in first-out (queuing method)
FMMU Fieldbus memory management unit
FoE File access with Type 12 services
HDR Header
ID Identifier
IETF Internet engineering task force
IP Internet protocol
LAN Local area network
MAC Medium access control
OD Object dictionary
OSI Open systems interconnection
PDI Physical device internal interface (a set of elements that allows access to DL-services from the
AL)
PDO Process data object
PhL Ph-layer
QoS Quality of service
RAM Random access memory
Rx Receive
SDO Service data object
SII slave information interface
SM Synchronization manager
SyncM Synchronization manager
TCP Transmission control protocol
Tx Transmit
UDP User datagram protocol
WKC Working counter
3.5 Conventions
This standard uses the descriptive conventions given in ISO/IEC 10731.
The service model, service primitives, and time-sequence diagrams used are entirely abstract
descriptions; they do not represent a specification for implementation.
Service primitives, used to represent service user/service provider interactions (see
ISO/IEC 10731), convey parameters that indicate information available in the user/provider
interaction.
This standard uses a tabular format to describe the component parameters of the service
primitives. The parameters that apply to each group of service primitives are set out in tables

throughout the remainder of this standard. Each table consists of up to five columns,

containing the name of the service parameter, and a column each for those primitives and

parameter-transfer directions used by the servi
...