IEC 61158-3-16:2007

IEC 61158-3-16 ®
Edition 1.0 2007-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Industrial communication networks – Fieldbus specifications –
Part 3-16: Data-link layer service definition – Type 16 elements

Réseaux de communication industriels – Spécifications des bus de terrain –
Partie 3-16: Définition du service de la couche de liaison de données –
Éléments de Type 16
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form
or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from
either IEC or IEC's member National Committee in the country of the requester.
If you have any questions about IEC copyright or have an enquiry about obtaining additional rights to this publication,
please contact the address below or your local IEC member National Committee for further information.

Droits de reproduction réservés. Sauf indication contraire, aucune partie de cette publication ne peut être reproduite ni
utilisée sous quelque forme que ce soit et par aucun procédé, électronique ou mécanique, y compris la photocopie et les
microfilms, sans l'accord écrit de la CEI ou du Comité national de la CEI du pays du demandeur.
Si vous avez des questions sur le copyright de la CEI ou si vous désirez obtenir des droits supplémentaires sur cette
publication, utilisez les coordonnées ci-après ou contactez le Comité national de la CEI de votre pays de résidence.

IEC Central Office Tel.: +41 22 919 02 11
3, rue de Varembé Fax: +41 22 919 03 00
CH-1211 Geneva 20 info@iec.ch
Switzerland www.iec.ch
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.

About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigenda or an amendment might have been published.

Useful links:
IEC publications search - www.iec.ch/searchpub Electropedia - www.electropedia.org
The advanced search enables you to find IEC publications The world's leading online dictionary of electronic and
by a variety of criteria (reference number, text, technical electrical terms containing more than 30 000 terms and
committee,…). definitions in English and French, with equivalent terms in
It also gives information on projects, replaced and additional languages. Also known as the International
withdrawn publications. Electrotechnical Vocabulary (IEV) on-line.

IEC Just Published - webstore.iec.ch/justpublished Customer Service Centre - webstore.iec.ch/csc
Stay up to date on all new IEC publications. Just Published If you wish to give us your feedback on this publication
details all new publications released. Available on-line and or need further assistance, please contact the
also once a month by email. Customer Service Centre: csc@iec.ch.

A propos de la CEI
La Commission Electrotechnique Internationale (CEI) est la première organisation mondiale qui élabore et publie des
Normes internationales pour tout ce qui a trait à l'électricité, à l'électronique et aux technologies apparentées.

A propos des publications CEI
Le contenu technique des publications de la CEI est constamment revu. Veuillez vous assurer que vous possédez
l’édition la plus récente, un corrigendum ou amendement peut avoir été publié.

Liens utiles:
Recherche de publications CEI - www.iec.ch/searchpub Electropedia - www.electropedia.org
La recherche avancée vous permet de trouver des Le premier dictionnaire en ligne au monde de termes
publications CEI en utilisant différents critères (numéro de électroniques et électriques. Il contient plus de 30 000
référence, texte, comité d’études,…). termes et définitions en anglais et en français, ainsi que
Elle donne aussi des informations sur les projets et les les termes équivalents dans les langues additionnelles.
publications remplacées ou retirées. Egalement appelé Vocabulaire Electrotechnique
International (VEI) en ligne.
Just Published CEI - webstore.iec.ch/justpublished
Service Clients - webstore.iec.ch/csc
Restez informé sur les nouvelles publications de la CEI.
Just Published détaille les nouvelles publications parues. Si vous désirez nous donner des commentaires sur
Disponible en ligne et aussi une fois par mois par email. cette publication ou si vous avez des questions
contactez-nous: csc@iec.ch.
IEC 61158-3-16 ®
Edition 1.0 2007-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Industrial communication networks – Fieldbus specifications –

Part 3-16: Data-link layer service definition – Type 16 elements

Réseaux de communication industriels – Spécifications des bus de terrain –

Partie 3-16: Définition du service de la couche de liaison de données –

Éléments de Type 16
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX T
ICS 25.040.40; 35.100.20 ISBN 978-2-8322-0984-4

– 2 – 61158-3-16 © IEC:2007
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
1.1 Overview . 6
1.2 Specifications . 6
1.3 Conformance . 6
2 Normative references . 7
3 Terms, definitions, symbols, abbreviations and conventions . 7
3.1 Reference model terms and definitions . 7
3.2 Service convention terms and definitions . 8
3.3 Data-link service terms and definitions . 9
3.4 Symbols and abbreviations . 12
3.5 Common conventions . 13
4 Data-link services and concepts . 14
4.1 Overview . 14
4.2 Service channel services (SVC services) . 16
4.3 Realtime channel setup services (RTCS services) . 18
4.4 RTC services . 20
4.5 File transmission services . 23
Bibliography . 25

Figure 1 – Relationships of DLSAPs, DLSAP-addresses and group DL-addresses . 10

Table 1 – Summary of DL services and primitives . 16
Table 2 – Read (RD) . 17
Table 3 – Write (WR) . 18
Table 4 – Initiate_cyclic_communication (ICC) . 19
Table 5 – Disable_cyclic_communication (DCC) . 20
Table 6 – Notify_Error (NER) . 20
Table 7 – Write_cyclic (WRC) . 21
Table 8 – Get_Device_Status (GDS) . 21
Table 9 – Write_Device_Status (SDS). 22
Table 10 – Notify_Network_Status_Change (NNSC) . 22
Table 11 – File download (FD) . 23
Table 12 – File upload (FU) . 23

61158-3-16 © IEC:2007 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
INDUSTRIAL COMMUNICATION NETWORKS –
FIELDBUS SPECIFICATIONS –
Part 3-16: Data-link layer service definition – Type 16 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 provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with an IEC Publication.
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.
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 IEC 61784 series. Use of the various protocol types in other
combinations may require permission of their respective intellectual-property-right holders.
International Standard IEC 61158-3-16 has been prepared by subcommittee 65C: Industrial
networks, of IEC technical committee 65: Industrial-process measurement, control and
automation.
This first edition and its companion parts of the IEC 61158-3 subseries cancel and replace
IEC 61158-3:2003. This edition of this part constitutes a technical addition. This publication,
together with its companion parts for Type 16, also partially replaces IEC 61491:2002 which is
at present being revised. IEC 61491 will be issued as a technical report.
This edition includes the following significant changes with respect to the previous edition:
a) deletion of the former Type 6 fieldbus, and the placeholder for a Type 5 fieldbus data-link
layer, for lack of market relevance;
b) addition of new types of fieldbuses;

– 4 – 61158-3-16 © IEC:2007
c) division of this part into multiple parts numbered 3-1, 3-2, …, 3-19.
This bilingual version (2013-07) corresponds to the monolingual English version, published in
2007-12.
The text of this standard is based on the following documents:
FDIS Report on voting
65C/473/FDIS 65C/484/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.
The French version of this standard has not been voted upon.
This publication has been drafted in accordance with ISO/IEC Directives, Part 2.
The committee has decided that the contents of this publication will remain unchanged until
the maintenance result 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.
The list of all the parts of the IEC 61158 series, under the general title Industrial
communication networks – Fieldbus specifications, can be found on the IEC web site.

61158-3-16 © IEC:2007 – 5 –
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.
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 data-link layer service defined in this standard is a conceptual architectural service,
independent of administrative and implementation divisions.

– 6 – 61158-3-16 © IEC:2007
INDUSTRIAL COMMUNICATION NETWORKS –
FIELDBUS SPECIFICATIONS –
Part 3-16: Data-link layer service definition – Type 16 elements

1 Scope
1.1 Overview
This standard provides common elements for basic time-critical messaging communications
between devices in an automation environment. 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 Type
16 fieldbus data-link layer in terms of
a) the primitive actions and events of the service;
b) the parameters associated with each primitive action and event, and the form which they
take; and
c) the interrelationship between these actions and events, and their valid sequences.
The purpose of this standard is to define the services provided to
• the Type 16 fieldbus application layer at the boundary between the application and data-
link layers of the fieldbus reference model, and
• systems management at the boundary between the data-link layer and systems
management of the fieldbus reference model.
1.2 Specifications
The principal objective of this standard is to specify the characteristics of conceptual data-link
layer services suitable for time-critical communications, and thus supplement the OSI Basic
Reference Model in guiding the development of data-link protocols for time-critical
communications. A secondary objective is to provide migration paths from previously-existing
industrial communications protocols.
This specification may be used as the basis for formal DL-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 do they constrain
the implementations of data-link entities within industrial automation systems.
There is no conformance of equipment to this data-link layer service definition standard.
Instead, conformance is achieved through implementation of the corresponding data-link
protocol that fulfills the Type 16 data-link layer services defined in this standard.

61158-3-16 © IEC:2007 – 7 –
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.
ISO/IEC 7498-1, Information technology – Open Systems Interconnection – Basic Reference
Model: The Basic Model
ISO/IEC 7498-3, Information technology – Open Systems Interconnection – Basic Reference
Model: Naming and addressing
ISO/IEC 10731, Information technology – Open Systems Interconnection – Basic Reference
Model – Conventions for the definition of OSI services
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 DL-address [7498-3]
3.1.2 DL-address-mapping [7498-1]
3.1.3 called-DL-address [7498-3]
3.1.4 calling-DL-address [7498-3]
3.1.5 centralized multi-end-point-connection [7498-1]
3.1.6 DL-connection [7498-1]
3.1.7 DL-connection-end-point [7498-1]
3.1.8 DL-connection-end-point-identifier [7498-1]
3.1.9 DL-connection-mode transmission [7498-1]
3.1.10 DL-connectionless-mode transmission [7498-1]
3.1.11 correspondent (N)-entities [7498-1]
correspondent DL-entities  (N=2)
correspondent Ph-entities  (N=1)
3.1.12 DL-duplex-transmission [7498-1]
3.1.13 (N)-entity [7498-1]
DL-entity  (N=2)
Ph-entity  (N=1)
3.1.14 DL-facility [7498-1]
3.1.15 flow control [7498-1]
– 8 – 61158-3-16 © IEC:2007
3.1.16 (N)-layer [7498-1]
DL-layer  (N=2)
Ph-layer  (N=1)
3.1.17 layer-management [7498-1]
3.1.18 DL-local-view [7498-3]
3.1.19 DL-name [7498-3]
3.1.20 naming-(addressing)-domain [7498-3]
3.1.21 peer-entities [7498-1]
3.1.22 primitive name [7498-3]
3.1.23 DL-protocol [7498-1]
3.1.24 DL-protocol-connection-identifier [7498-1]
3.1.25 DL-protocol-data-unit [7498-1]
3.1.26 DL-relay [7498-1]
3.1.27 reset [7498-1]
3.1.28 responding-DL-address [7498-3]
3.1.29 routing [7498-1]
3.1.30 segmenting [7498-1]
3.1.31 (N)-service [7498-1]
DL-service  (N=2)
Ph-service  (N=1)
3.1.32 (N)-service-access-point [7498-1]
DL-service-access-point  (N=2)
Ph-service-access-point  (N=1)
3.1.33 DL-service-access-point-address [7498-3]
3.1.34 DL-service-connection-identifier [7498-1]
3.1.35 DL-service-data-unit
[7498-1]
3.1.36 DL-simplex-transmission [7498-1]
3.1.37 DL-subsystem [7498-1]
3.1.38 systems-management [7498-1]
3.1.39 DL-user-data [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
61158-3-16 © IEC:2007 – 9 –
3.2.3 confirm (primitive);
requestor.deliver (primitive)
3.2.4 deliver (primitive)
3.2.5 DL-confirmed-facility
3.2.6 DL-facility
3.2.7 DL-local-view
3.2.8 DL-mandatory-facility
3.2.9 DL-non-confirmed-facility
3.2.10 DL-provider-initiated-facility
3.2.11 DL-provider-optional-facility
3.2.12 DL-service-primitive;
primitive
3.2.13 DL-service-provider
3.2.14 DL-service-user
3.2.15 DL-user-optional-facility
3.2.16 indication (primitive);
acceptor.deliver (primitive)
3.2.17 multi-peer
3.2.18 request (primitive);
requestor.submit (primitive)
3.2.19 requestor
3.2.20 response (primitive);
acceptor.submit (primitive)
3.2.21 submit (primitive)
3.2.22 symmetrical service
3.3 Data-link service terms and definitions
3.3.1
cycle time
duration of a communication cycle
3.3.2
cyclic communication
periodic exchange of telegrams
3.3.3
cyclic data
part of a telegram, which does not change its meaning during cyclic operation of the network
3.3.4
cyclic operation
operation in which devices in the communication network are addressed and queried one after
the other at fixed, constant time intervals

– 10 – 61158-3-16 © IEC:2007
3.3.5
device
a slave in the communication network, (e.g., a power drive system as defined in the
IEC 61800 standard family, I/O stations as defined in the IEC 61131 standard family)
3.3.6
device status
four adjacent octets inside the acknowledge telegram containing status information for each
device
3.3.7
DL-segment, link, local link
single DL-subnetwork in which any of the connected DLEs may communicate directly, without
any intervening DL-relaying, whenever all of those DLEs that are participating in an instance
of communication are simultaneously attentive to the DL-subnetwork during the period(s) of
attempted communication
NOTE 1 DLSAPs and PhSAPs are depicted as ovals spanning the boundary between two adjacent layers.
NOTE 2 DL-addresses are depicted as designating small gaps (points of access) in the DLL portion of a DLSAP.
NOTE 3 A single DL-entity may have multiple DLSAP-addresses and group DL-addresses associated with a
single DLSAP.
Figure 1 – Relationships of DLSAPs, DLSAP-addresses and group DL-addresses
3.3.8
DLSAP
distinctive point at which DL-services are provided by a single DL-entity to a single higher-
layer entity
NOTE This definition, derived from ISO/IEC 7498-1, is repeated here to facilitate understanding of the critical
distinction between DLSAPs and their DL-addresses.

61158-3-16 © IEC:2007 – 11 –
3.3.9
DL(SAP)-address
either an individual DLSAP-address, designating a single DLSAP of a single DLS-user, or a
group DL-address potentially designating multiple DLSAPs, each of a single DLS-user
NOTE This terminology is chosen because ISO/IEC 7498-3 does not permit the use of the term DLSAP-address
to designate more than a single DLSAP at a single DLS-user.
3.3.10
(individual) DLSAP-address
DL-address that designates only one DLSAP within the extended link
NOTE A single DL-entity may have multiple DLSAP-addresses associated with a single DLSAP.
3.3.11
element
part of IDNs – each IDN has 7 elements, whereas each one has a specific meaning (e.g.,
number, name, data)
3.3.12
extended link
DL-subnetwork, consisting of the maximal set of links interconnected by DL-relays, sharing a
single DL-name (DL-address) space, in which any of the connected DL-entities may
communicate, one with another, either directly or with the assistance of one or more of those
intervening DL-relay entities
NOTE An extended link may be composed of just a single link.
3.3.13
frame
denigrated synonym for DLPDU
3.3.14
group DL-address
DL-address that potentially designates more than one DLSAP within the extended link. A
single DL-entity may have multiple group DL-addresses associated with a single DLSAP. A
single DL-entity also may have a single group DL-address associated with more than one
DLSAP
3.3.15
hot plug
possibility to open the communication network and insert or remove slaves while the network
is still in real-time operation
3.3.16
identification number (IDN)
designation of operating data under which a data block is preserved with its attribute, name,
unit, minimum and maximum input values, and the data
3.3.17
node
single DL-entity as it appears on one local link
3.3.18
protocol
convention about the data formats, time sequences, and error correction in the data exchange
of communication systems
3.3.19
receiving DLS-user
DL-service user that acts as a recipient of DL-user-data

– 12 – 61158-3-16 © IEC:2007
NOTE A DL-service user can be concurrently both a sending and receiving DLS-user.
3.3.20
sending DLS-user
DL-service user that acts as a source of DL-user-data
3.3.21
service channel (SVC)
non real-time transmission of information upon master request during RT channel
3.3.22
slave
node, which is assigned the right to transmit by the master
3.3.23
station
node
3.3.24
telegram
frame
3.3.25
topology
physical network architecture with respect to the connection between the stations of the
communication system
3.4 Symbols and abbreviations
3.4.1 DL- Data-link layer (as a prefix)
3.4.2 DLC DL-connection
3.4.3 DLCEP DL-connection-end-point
3.4.4 DLE DL-entity (the local active instance of the data-link layer)
3.4.5 DLL DL-layer
3.4.6 DLPCI DL-protocol-control-information
3.4.7 DLPDU DL-protocol-data-unit
3.4.8 DLM DL-management
3.4.9 DLME DL-management Entity (the local active instance of
DL-management)
3.4.10 DLMS DL-management Service
3.4.11 DLS DL-service
3.4.12 DLSAP DL-service-access-point
3.4.13 DLSDU DL-service-data-unit
3.4.14 FIFO First-in first-out (queuing method)
3.4.15 IDN Identification Number
3.4.16 OSI Open systems interconnection

61158-3-16 © IEC:2007 – 13 –
3.4.17 Ph- Physical layer (as a prefix)
3.4.18 PhE Ph-entity (the local active instance of the physical layer)
3.4.19 PhL Ph-layer
3.4.20 QoS Quality of service
3.4.21 RE Resource element
3.4.22 RTC Real-time channel
3.4.23 SI Sub Index
3.4.24 SVC Service channel
3.5 Common 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 DLS
primitives. The parameters that apply to each group of DLS primitives are set out in tables
throughout the remainder of this standard. Each table consists of up to six columns,
containing the name of the service parameter, and a column each for those primitives and
parameter-transfer directions used by the DLS:
 the request primitive’s input parameters;
 the request primitive’s output parameters;
 the indication primitive’s output parameters;
 the response primitive’s input parameters; and
 the confirm primitive’s output parameters.
NOTE The request, indication, response and confirm primitives are also known as requestor.submit,
acceptor.deliver, acceptor.submit, and requestor.deliver primitives, respectively (see ISO/IEC 10731).
One parameter (or part of it) is listed in each row of each table. Under the appropriate service
primitive columns, a code is used to specify the type of usage of the parameter on the
primitive and parameter direction specified in the column:
M — parameter is mandatory for the primitive.
U — parameter is a User option, and may or may not be provided depending on
the dynamic usage of the DLS-user. When not provided, a default value for
the parameter is assumed.
C — parameter is conditional upon other parameters or upon the environment of
the DLS-user.
(blank) — parameter is never present.
Some entries are further qualified by items in brackets. These may be
a) a parameter-specific constraint

– 14 – 61158-3-16 © IEC:2007
(=) indicates that the parameter is semantically equivalent to the parameter in the
service primitive to its immediate left in the table;
b) an indication that some note applies to the entry
(n) indicates that the following note n contains additional information pertaining to the
parameter and its use.
In any particular interface, not all parameters need be explicitly stated. Some may be
implicitly associated with the DLSAP at which the primitive is issued.
In the diagrams which illustrate these interfaces, dashed lines indicate cause-and-effect or
time-sequence relationships, and wavy lines indicate that events are roughly
contemporaneous.
4 Data-link services and concepts
4.1 Overview
The data-link layer specifies services for reading and writing data from devices in a Type 16
network. The mechanisms for using these services are related to the Type 16 specific
Identification Numbers (IDN). There are three different types of services:
• Service channel services (confirmed, non-cyclic)
• File transfer services (confirmed, non-cyclic)
• Real-time channel setup services (confirmed, non-cyclic)
• Real-time channel services (confirmed, cyclic).
Table 1 gives a Summary of DL services and primitives.
4.1.1 Acknowledged connection oriented data transfer: Read (RD)
This service permits the local DLS-user to send a DLSDU to a single remote station. At the
remote station the DLSDU, if the respective DLPDU is transferred error-free, is delivered by
the remote DLE to its local DLS-user and answered by it. This response is send back. The
originating local DLS-user receives a confirmation answer of the DLSDU by the remote DLS-
user. If an error occurred during the transfer, the originating DLE repeats the data transfer up
to a configured maximum number of times.
4.1.2 Acknowledged connection oriented data transfer: Read (WR)
This service permits the local DLS-user to send a DLSDU to a single remote station. At the
remote station the DLSDU, if the respective DLPDU is transferred error-free, is delivered by
the remote DLE to its local DLS-user and answered by it. This response is send back. The
originating local DLS-user receives a confirmation answer of the DLSDU by the remote DLS-
user. If an error occurred during the transfer, the originating DLE repeats the data transfer up
to a configured maximum number of times.
4.1.3 Acknowledged connection oriented data transfer: Initiate_cyclic_communication
(ICC)
This service permits the local DLS-user to send a DLSDU to a several remote station. At the
remote station the DLSDU, if the respective DLPDU is transferred error-free, is delivered by
the remote DLE to its local DLS-user and answered by it. This response is send back. The
originating local DLS-user receives a confirmation answer of the DLSDU by the remote DLS-
user. If an error occurred during the transfer, the originating DLE repeats the data transfer up
to a configured maximum number of times.

61158-3-16 © IEC:2007 – 15 –
4.1.4 Acknowledged connection oriented data transfer: Disable_cyclic_communication
(DCC)
This service permits the local DLS-user to send a DLSDU to remote stations. At the remote
station the DLSDU, if the respective DLPDU is transferred error-free, is delivered by the
remote DLE to its local DLS-user and answered by it. This response is send back. The
originating local DLS-user receives a confirmation answer of the DLSDU by the remote DLS-
user. If an error occurred during the transfer, the originating DLE repeats the data transfer up
to a configured maximum number of times.
4.1.5 Unacknowledged connectionless data transfer: Write_cyclic (WRC)
This service permits a local DLS-user to transfer a DLSDU to a single remote station or a list
of stations. The local DLS-user receives a confirmation acknowledging the completion of the
transfer, but not whether the DLPDU was duly received. At each addressed remote station
this DLSDU, if the respective DLPDU is received error-free, is delivered to a single local DLS-
user. There is no confirmation to the sending DLS-user that such an intended delivery has
taken place.
4.1.6 Unacknowledged connectionless data transfer: Send_Device_Status (SDS)
This service permits a local DLS-user to transfer a DLSDU to a single remote station . The
local DLS-user receives a confirmation acknowledging the completion of the transfer, but not
whether the DLPDU was duly received. At the addressed remote station this DLSDU, if the
respective DLPDU is received error-free, is delivered to a single local DLS-user. There is no
confirmation to the sending DLS-user that such an intended delivery has taken place.
4.1.7 Unacknowledged connectionless data transfer: Write_Device_Status (WDS)
This service permits a local DLS-user to transfer a DLSDU to a single remote station . The
local DLS-user receives a confirmation acknowledging the completion of the transfer, but not
whether the DLPDU was duly received. At the addressed remote station this DLSDU, if the
respective DLPDU is received error-free, is delivered to a single local DLS-user. There is no
confirmation to the sending DLS-user that such an intended delivery has taken place.
4.1.8 Acknowledged connection oriented data transfer: File download (FD)
This service permits the local DLS-user to send a DLSDU to remote stations. At the remote
station the DLSDU, if the respective DLPDU is transferred error-free, is delivered by the
remote DLE to its local DLS-user and answered by it. This response is send back. The
originating local DLS-user receives a confirmation answer of the DLSDU by the remote DLS-
user. If an error occurred during the transfer, the originating DLE repeats the data transfer up
to a configured maximum number of times.
4.1.9 Acknowledged connection oriented data transfer: File download (FD)
This service permits the local DLS-user to send a DLSDU to remote stations. At the remote
station the DLSDU, if the respective DLPDU is transferred error-free, is delivered by the
remote DLE to its local DLS-user and answered by it. This response is send back. The
originating local DLS-user receives a confirmation answer of the DLSDU by the remote DLS-
user. If an error occurred during the transfer, the originating DLE repeats the data transfer up
to a configured maximum number of times.

– 16 – 61158-3-16 © IEC:2007
Table 1 – Summary of DL services and primitives
Service Primitive Possible for these station classes
Acknowledged connection oriented data transfer: DL-RD request Master
Read (RD) DL-RD confirm
DL-RD indication Slave
DL-RD response
Acknowledged connection oriented data transfer: DL-WR request Master
Write (WR) DL-WR confirm
DL-WR indication Slave
DL-WR response
Acknowledged connection oriented data transfer: DL-ICC request Master
Initiate_cyclic_communication (ICC) DL-ICC confirm
DL-ICC indication Slave
DL-ICC response
Acknowledged connection oriented data transfer: DL-DCC request Master
Disable_cyclic_communication (DCC) DL-DCC confirm
DL-DCC indication Slave
DL-DCC response
Unacknowledged connectionless data transfer: DL-WRC request Master or Slave
Write_cyclic (WRC) DL-WRC confirm
DL-WRC indication Slave or Master
Unacknowledged connectionless data transfer: DL-SDS request Slave
Send_Device_Status (SDS) DL-SDS confirm
DL-SDS indication Master
Unacknowledged connectionless data transfer: DL-WDS request Master
Write_Device_Status (WDS) DL-WDS confirm
DL-WDS indication Slave
Acknowledged connection oriented data transfer: DL-FD request Master
File download (FD) DL-FD confirm
DL-FD indication Slave
DL-FD response
Acknowledged connection oriented data transfer: DL-FU request Master
File upload (FU) DL-FU confirm
DL-FU indication Slave
DL-FU response
4.2 Service channel services (SVC services)
With the services of the service channel, a master reads or writes elements of an IDN of a
slave device.
4.2.1 Read (RD)
4.2.1.1 Function
With the RD service, a master reads elements of an IDN from one device selected by a device
address (see Table 2).
61158-3-16 © IEC:2007 – 17 –
Table 2 – Read (RD)
Request Indication Response Confirmation
Parameter name
input output input output
Device address M M (=)
IDN M M (=)
Element M M (=)
Data  M M (=)
Error code  M M (=)
NOTE The method by which a confirm primitive is correlated with its corresponding preceding
request primitive is a local matter. The method by which a response primitive is correlated
with its corresponding preceding indication primitive is a local matter. See 1.2.

4.2.1.2 Request and Indication parameters
4.2.1.2.1 Device address
This parameter is used to address the device from which the data is to be read.
4.2.1.2.2 IDN
This parameter is used to identify the IDN from which the data is to beread.
4.2.1.2.3 Element
This parameter is used to identify the element of the IDN that is to be read.
4.2.1.3 Response and confirmation parameters
The result is used to convey the service specific parameters of the service response.
4.2.1.3.1 Data
This parameter specifies the data which was read from the device.
4.2.1.3.2 Error code
This parameter specifies the error code of the read request.
4.2.2 Write (WR)
4.2.2.1 Function
With the Write services a master writes elements of an IDN to one device selected by a
device address (see Table 3).
– 18 – 61158-3-16 © IEC:2007
Table 3 – Write (WR)
Request Indication Response Confirmation
Parameter name
input output input output
Device address M M (=)
IDN M M (=)
Element M M (=)
Data M M (=)
Error code  M M (=)
NOTE The method by which a confirm primitive is correlated with its corresponding preceding
request primitive is a local matter. The method by which a response primitive is correlated
with its corresponding preceding indication primitive is a local matter. See 1.2.

4.2.2.2 Request and Indication parameters
4.2.2.2.1 Device address
This parameter is used to address the device to which the data is to be written.
4.2.2.2.2 IDN
This parameter is used to identify the IDN from which the data is to be written.
4.2.2.2.3 Element
This parameter is used to identify the element of the IDN that is to be written.
4.2.2.2.4 Data
This parameter specifies the data which is written to the device.
4.2.2.3 Response and confirmation parameters
The result conveys the service specific parameters of the service response.
4.2.2.3.1 Error code
This parameter specifies the error code of the write request.
4.3 Realtime channel setup services (RTCS services)
With the Realtime channel setup services, a master establishes the cyclic communication.
4.3.1 Initiate_cyclic_communication (ICC)
4.3.1.1 Function
With the ICC service, a master initiates the cyclic communication with the slave devices in a
Type 16 network (see Table 4).

61158-3-16 © IEC:2007 – 19 –
Table 4 – Initiate_cyclic_communication (ICC)
Request Indication Response Confirmation
Parameter name
input output input output
Baud rate M M (=)
Cycle time M M (=)
List of device addresses M M (=)
List of MS input data length for all devices M M (=)
List of offset of MS input data for all devices M M (=)
List of MS output data length for all devices M M (=)
List of offset MS output data for all devices M M (=)
Error code  M M (=)
NOTE The method by which a confirm primitive is correlated with its corresponding preceding request
primitive is a local matter. The method by which a response primitive is correlated with its
corresponding preceding indication primitive is a local matter. See 1.2.

4.3.1.2 Request and Indication parameters
4.3.1.2.1 Baud rate
This parameter is used to define the baud rate of the communication.
4.3.1.2.2 Cycle time
This parameter is used to define the cycle time of the communication.
4.3.1.2.3 List of device addresses
This parameter is used to define the addresses of all devices which are included in the cyclic
communication.
4.3.1.2.4 List of length of input data for all devices
This parameter is used to define the length of input data for all devices which are included in
the cyclic communication.
4.3.1.2.5 List of offsets of input data for all devices
This parameter is used to define the offsets of all devices for transmitting data.
4.3.1.2.6 List of length of output data for all devices
This parameter is used to define the length of output data for all devices which are included in
the cyclic communication.
4.3.1.2.7 List of offsets for output data for all devices
This parameter is used to define the offsets of all devices for receiving data.
4.3.1.3 Response and Confirmation parameters
4.3.1.3.1 Error code
This parameter specifies the error code of the initiate request.

– 20 – 61158-3-16 © IEC:2007
4.3.2 Disable_cyclic_communication (DCC)
4.3.2.1 Function
With the DCC service, a master disables the cyclic communication with the slave devices in a
Type 16 network (see Table 5).
Table 5 – Disable_cyclic_communication (DCC)
Request Indication Response Confirmation
Parameter name
input output input output
List of device addresses M M (=)
Error code  M M(=)
NOTE The method by which a confirm primitive is correlated with its corresponding preceding
request primitive is a local matter. The method by which a response primitive is correlated
with its corresponding preceding indication primitive is a local matter. See 1.2.

4.3.2.2 Request and Indication parameters
4.3.2.2.1 List of Device Addresses
This Parameter specifies the list of device addresses with which the cyclic communication is
to be disabled.
4.3.2.3 Response and Confirmation paramete
...