IEC 61158-3-19:2014

IEC 61158-3-19 ®
Edition 3.0 2014-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Industrial communication networks – Fieldbus specifications –
Part 3-19: Data-link layer service definition – Type 19 elements

Réseaux de communication industriels – Spécifications des bus de terrain –
Partie 3-19: Définition des services de la couche liaison de données – Eléments
de type 19
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IEC 61158-3-19 ®
Edition 3.0 2014-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Industrial communication networks – Fieldbus specifications –

Part 3-19: Data-link layer service definition – Type 19 elements

Réseaux de communication industriels – Spécifications des bus de terrain –

Partie 3-19: Définition des services de la couche liaison de données – Eléments

de type 19
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX T
ICS 25.040.40; 35.100.20; 35.110 ISBN 978-2-8322-1716-0

– 2 – IEC 61158-3-19:2014 © IEC 2014

CONTENTS
FOREWORD . 3

INTRODUCTION . 5

1 Scope . 6

1.1 General . 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 . 14
4 Data-link services and concepts . 15
4.1 Overview . 15
4.2 Service channel services (SVC services) . 16
4.3 Hot-plug services . 18
4.4 Realtime channel setup services (RTCS services) . 19
4.5 RTC services . 21
Bibliography . 24

Figure 1 – Relationships of DLSAPs, DLSAP-addresses and group DL-addresses . 11

Table 1 – Summary of DL services and primitives . 15
Table 2 – Read (RD) . 17
Table 3 – Write (WR) . 18
Table 4 – Enable_Hotplug (EHP) . 19
Table 5 – Notify_Hotplug (NHP) . 19
Table 6 – Initiate_cyclic_communication (ICC) . 20
Table 7 – Disable_cyclic_communication (DCC) . 21
Table 8 – Notify_Error (NER) . 21

Table 9 – Write_cyclic (WRC) . 21
Table 10 – Send_Device_Status (SDS) . 22
Table 11 – Write_Device_Status (WDS) . 23
Table 12 – Notify_Network_Status_Change (NNSC) . 23

INTERNATIONAL ELECTROTECHNICAL COMMISSION

____________
INDUSTRIAL COMMUNICATION NETWORKS –

FIELDBUS SPECIFICATIONS –
Part 3-19: Data-link layer service definition –

Type 19 elements
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
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6) All users should ensure that they have the latest edition of this publication.
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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 61158-3-19 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:
– 4 – IEC 61158-3-19:2014 © IEC 2014

• introducing connections based on a producer-consumer model;

• introducing additional mechanisms to realize features such as timestamping and
oversampling;
• improving the hotplug and redundancy features;

• improving the phase switching and the error handling;

• editorial improvements.
The text of this standard is based on the following documents:

FDIS Report on voting
65C/759/FDIS 65C/769/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.

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 – IEC 61158-3-19:2014 © IEC 2014

INDUSTRIAL COMMUNICATION NETWORKS –

FIELDBUS SPECIFICATIONS –
Part 3-19: Data-link layer service definition –

Type 19 elements
1 Scope
1.1 General
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
19 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 19 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 standard 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 19 data-link layer services 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.
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]
– 8 – IEC 61158-3-19:2014 © IEC 2014

3.1.15 flow control [7498-1]
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
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
For the purposes of this document, the following terms and definitions apply.
3.3.1
communication cycle
fixed time period between two master synchronization telegrams in which real-time telegrams
are transmitted in the RT channel and non real-time telegrams are transmitted in the IP
channel
3.3.2
cycle time
duration of a communication cycle

– 10 – IEC 61158-3-19:2014 © IEC 2014

3.3.3
cyclic communication
periodic exchange of telegrams

3.3.4
cyclic data
part of a telegram, which does not change its meaning during cyclic operation of the network

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
3.3.8
DLSAP
distinctive point at which DL-services are provided by a single DL-entity to a single higher-
layer entity
Note 1 to entry: This definition, derived from ISO/IEC 7498-1, is repeated here to facilitate understanding of the
critical distinction between DLSAPs and their DL-addresses (see Figure 1).

DLS-user-entity
DLS-user-entity
DLS-users
DLSAP DLSAP DLSAP
DLSAP-
address DLSAP-
DLSAP-
group DL-
address
addresses
address
DL-layer
DL-entity
PhSA P PhSA P
Ph-layer
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
3.3.9
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 1 to entry: 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 1 to entry: 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 1 to entry: An extended link may be composed of just a single link.

– 12 – IEC 61158-3-19:2014 © IEC 2014

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.

Note 1 to entry: 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
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
3.3.16
master
node, which assigns the other nodes (i.e., slaves) the right to transmit
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
Note 1 to entry: 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
topology
physical network architecture with respect to the connection between the stations of the
communication system
3.4 Symbols and abbreviations
AT Acknowledge telegram
CA Procedure command acknowledgment

CC Cross communication between participants

DA Destination address
DAT Duration of acknowledge telegram

DL- Data-link layer (as a prefix)

DLC DL-connection
DLCEP DL-connection-end-point
DLE DL-entity (the local active instance of the data-link layer)
DLL DL-layer
DLPCI DL-protocol-control-information
DLPDU DL-protocol-data-unit
DLM DL-management
DLME DL-management entity (the local active instance of DL-management)
DLMS DL-management service
DLS DL-service
DLSAP DL-service-access-point
DLSDU DL-service-data-unit
FIFO First-in first-out (queuing method)
HS service channel handshake (see AHS and MHS)
IDN Identification number
INFO service channel information
MC motion control or motion controller (see also NC)
NC numerical control (also control unit or controller)
OSI Open systems interconnection
Ph- Physical layer (as a prefix)

PhE Ph-entity (the local active instance of the physical layer)
PhL Ph-layer
QoS Quality of service
RE Resource element
RT real-time
RTC real-time channel
SA source address
SI Sub Index
SVC Service Channel
– 14 – IEC 61158-3-19:2014 © IEC 2014

XX address of a device
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
(=) 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 Type 19 services for reading and writing data from devices in a

Type 19 network (see Table 1). The mechanisms for using these services are related to the

Type 19 specific Identification Numbers (IDN). There are four different types of services:

• Service channel services (confirmed, non-cyclic)

• Hot-Plug services (confirmed and unconfirmed, non-cyclic)

• Real-time channel setup services (confirmed, non-cyclic)

• Real-time services (unconfirmed, cyclic).
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
Read (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
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.

– 16 – IEC 61158-3-19:2014 © IEC 2014

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.
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.
4.2 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).
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 be read.
4.2.1.2.3 Element
This parameter is used to identify the element of the IDN that is to be read. The element
consists of a data block element that is mandatory, a structure instance (SI) that is conditional
on the IDN and a structure element (SE) that is also conditional on the IDN. The structure
instance is used to address a specific function group instance, whereas the structure element
is used as an additional address which is related to a specific function group element.
4.2.1.3 Response and confirmation parameters
The result conveys 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 – IEC 61158-3-19:2014 © IEC 2014

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. The element
consists of a data block element that is mandatory, a structure instance (SI) that is conditional
on the IDN and a structure element (SE) that is also conditional on the IDN. The structure
instance is used to address a specific function group instance, whereas the structure element
is used as an additional address which is related to a specific function group element.
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 Hot-plug services
With the Hot-plug services, slave devices can be hot-plugged during normal operation.
4.3.1 Enable_Hotplug (EHP)
With the EHP service, a master enables the hot-plug capability in a Type 19 network (see
Table 4).
Table 4 – Enable_Hotplug (EHP)

Request
Parameter name
input output
List of device addresses M
M
Error code
4.3.1.1 Request input parameter

4.3.1.1.1 List of device addresses

This parameter is used to define the addresses of the devices that shall be hot-plugged.
If the list is empty, hot-plug shall be disabled.
4.3.1.2 Request output parameter
4.3.1.2.1 Error code
This parameter specifies the error code of the enable request.
4.3.2 Notify_Hotplug (NHP)
With the NHP service, the DL-user is notified that a hot-plug device is present in a Type 19
network (see Table 5).
Table 5 – Notify_Hotplug (NHP)
Indication
Parameter name output
Device address M
4.3.2.1 Indication parameters
4.3.2.1.1 Device address
This parameter is used to identify the device which has been hot-plugged.
4.4 Realtime channel setup services (RTCS services)
With the Realtime channel setup services, a master establishes the cyclic communication.

4.4.1 Initiate_cyclic_communication (ICC)
4.4.1.1 Function
With the ICC service, a master initiates the cyclic communication with the slave devices in a
Type 19 network (see
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