IEC 61158-6-9:2010

Industrial communication networks - Fieldbus specifications - Part 6-9: Application layer protocol specification - Type 9 elements

IEC 61158-6-9:2010(E) specifies the protocol of the Type 9 fieldbus application layer, in conformance with the OSI Basic Reference Model (ISO/IEC 7498-1) and the OSI application layer structure (ISO/IEC 9545). It defines the protocol provided to define the wire-representation of the service primitives defined in IEC 61158-5-5:2010, and the externally visible behavior associated with their transfer. This second edition cancels and replaces the first edition published in 2007 and constitutes a technical revision. The main changes with respect to the previous edition are: corrections, in Table 32.

General Information

• Status: Published
• Publication Date: 05-Aug-2010
• ICS: 25.040.40 - Industrial process measurement and control
• ICS: 35.100.70 - Application layer
• ICS: 35.110 - Networking
• Technical Committee: SC 65C - Industrial networks
• Drafting Committee: WG 9 - TC 65/SC 65C/WG 9
• Current Stage: DELPUB - Deleted Publication
• Start Date: 19-Aug-2014
• Completion Date: 26-Oct-2025

Relations

• Revises: IEC 61158-6-9:2007 - Industrial communication networks - Fieldbus specifications - Part 6-9: Application layer protocol specification - Type 9 elements
• Effective Date: 05-Sep-2023
• Revised: IEC 61158-6-9:2014 - Industrial communication networks - Fieldbus specifications - Part 6-9: Application layer protocol specification - Type 9 elements
• Effective Date: 05-Sep-2023

Overview

IEC 61158-6-9:2010 is an international standard that specifies the application layer protocol for Type 9 fieldbus elements within industrial communication networks. It defines the wire-representation (transfer syntax) of the service primitives described in IEC 61158-5-5:2010 and the externally visible behaviour of their transfer. The standard is aligned with the OSI Basic Reference Model (ISO/IEC 7498-1) and the OSI application layer structure (ISO/IEC 9545). Edition 2.0 (2010) cancels and replaces the 2007 edition and includes technical revisions (notably corrections in Table 32).

Key topics

• Application layer protocol: formal definition of messages and behaviours for Type 9 fieldbus application elements.
• Abstract syntax: FAL‑AR PDU and PDUBody structures, type definitions for application service elements (ASEs) and data types.
• Transfer syntax and coding rules: wire-level encoding for data types (Integer, Unsigned, Floating Point, Visible String, Octet String, Date/Time types, Bit String, Time-value) and identification information insertion.
• Protocol state machines: structure and state tables for FAL service protocol machine (FSPM), Application Relationship Protocol Machines (ARPMs: QUU, QUB, BNU, etc.), VCR PM and DLL mapping protocol machine (DMPM).
• Primitives and interfaces: definitions of primitives exchanged between FAL user, FSPM, ARPMs and the data-link layer; parameter lists and function definitions.
• Conformance and normative references: links to related IEC and ISO/IEC standards required for correct implementation.

Applications

IEC 61158-6-9 is intended for engineers and organizations implementing or validating fieldbus application-layer protocol stacks:

• Protocol implementers (firmware/software for PLCs, IO modules, gateways) who need precise wire-format and state-machine behaviour.
• Device manufacturers ensuring interoperability of Type 9 fieldbus devices on industrial networks.
• System integrators and control engineers deploying fieldbus-based automation systems.
• Test labs and certification bodies conducting conformance testing against application-layer behaviour.
• Network architects designing multi-vendor fieldbus solutions that rely on OSI-compliant application services.

Practical benefits include consistent device communication, predictable application-layer behaviour, and reduced integration effort in process and factory automation.

Related standards

• IEC 61158-5-5:2010 - defines the service primitives whose wire-representation is specified here.
• ISO/IEC 7498-1 - OSI Basic Reference Model.
• ISO/IEC 9545 - OSI application layer structure.
• Other parts of IEC 61158 (fieldbus specifications) for complementary protocol and profile definitions.

Keywords: IEC 61158-6-9, fieldbus, Type 9, application layer protocol, industrial communication networks, OSI model, protocol state machines, transfer syntax.

Standards Content (Sample)

IEC 61158-6-9 ®
Edition 2.0 2010-08
INTERNATIONAL
STANDARD
Industrial communication networks – Fieldbus specifications –
Part 6-9: Application layer protocol specification – Type 9 elements

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IEC 61158-6-9 ®
Edition 2.0 2010-08
INTERNATIONAL
STANDARD
Industrial communication networks – Fieldbus specifications –
Part 6-9: Application layer protocol specification – Type 9 elements

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
XD
ICS 25.04.40; 35.100.70; 35.110 ISBN 978-2-88912-127-4
– 2 – 61158-6-9 © IEC:2010(E)
CONTENTS
FOREWORD.5
INTRODUCTION.7
1 Scope.8
1.1 General .8
1.2 Specifications.8
1.3 Conformance.9
2 Normative references .9
3 Terms, definitions, symbols, abbreviations and conventions .9
3.1 Terms and definitions from other ISO/IEC standards .9
3.2 IEC/TR 61158-1 terms.10
3.3 Abbreviations and symbols.14
3.4 Conventions .15
3.5 Conventions used in state machines .15
4 Abstract syntax.16
4.1 FAL-AR PDU abstract syntax .16
4.2 Abstract syntax of PDUBody.19
4.3 Type definitions for ASEs .22
4.4 Abstract syntax of data types .27
5 Transfer syntax .28
5.1.1 General .28
5.1.2 Coding rules.28
5.1.3 Structure of the identification information .29
6 Structure of FAL protocol state machines .38
7 AP-Context state machines .40
7.1 VCR PM structure .40
7.2 VCR PM state machine .40
8 FAL service protocol machine (FSPM).52
8.1 General .52
8.2 FSPM state tables .52
8.3 Functions used by FSPM.55
8.4 Parameters of FSPM/ARPM primitives .55
9 Application relationship protocol machines (ARPMs) .55
9.1 AREP mapping to data-link layer .55
9.2 Application relationship protocol machines (ARPMs) .65
9.3 AREP state machine primitive definitions .81
9.4 AREP state machine functions .83
10 DLL mapping protocol machine (DMPM).84
10.1 DMPM States .84
10.2 DMPM state table.84
10.3 Primitives exchanged between data-link layer and DMPM .91
10.4 Functions used by DMPM.94
Bibliography.96

Figure 1 – Insertion of identification information in the FMS PDU.28
Figure 2 – Identification .29

61158-6-9 © IEC:2010(E) – 3 –
Figure 3 – Coding with identification .30
Figure 4 – Coding without identification .30
Figure 5 – Representation of the value true .30
Figure 6 – Representation of the value false .31
Figure 7 – Coding of data of data type Integer16 .31
Figure 8 – Coding of data of data type Unsigned16.32
Figure 9 – Coding of data of data type Floating Point.32
Figure 10 – Coding of data of data type Visible String.33
Figure 11 – Coding of data of data type Octet String.33
Figure 12 – Coding of data of type Date.34
Figure 13 – Coding of data of data type Time-of-day.35
Figure 14 – Coding of data of data type Time-difference .35
Figure 15 – Coding of data of data type Bit String .36
Figure 16 – Coding of data of data type Time-value .36
Figure 17 – Coding of data of user data definitions with identifier.37
Figure 18 – Coding of data of user data definitions without identifier.37
Figure 19 – Coding of ID info for a SEQUENCE .37
Figure 20 – Relationships among protocol machines and adjacent layers .39
Figure 21 – Relationships among protocol machines and adjacent layers .40
Figure 22 – VCR state machine .41
Figure 23 – State transition diagram of FSPM.52
Figure 24 – State transition diagram of the QUU ARPM .66
Figure 25 – State transition diagram of QUB ARPM .68
Figure 26 – State transition diagram of the BNU ARPM .76
Figure 27 – State transition diagram of DMPM .84

Table 1 – Conventions used for state machines .15
Table 2 – Coding for Date type .34
Table 3 – AP-VCR state machine transactions .42
Table 4 – Primitives issued by FAL-User to VCR PM .50
Table 5 – Primitives issued by VCR PM to FAL-User .51
Table 6 – Primitives issued by VCR PM to FSPM.51
Table 7 – Primitives issued by FSPM to VCR PM.52
Table 8 – FSPM state table – sender transactions .53
Table 9 – FSPM state table – receiver transactions .54
Table 10 – Function SelectArep().55
Table 11 – Parameters used with primitives exchanged between FSPM and ARPM .55
Table 12 – QUU ARPM states.66
Table 13 – QUU ARPM state table – sender transactions .66
Table 14 – QUU ARPM state table – receiver transactions.67
Table 15 – QUB ARPM states .68
Table 16 – QUB ARPM state table – sender transactions.69
Table 17 – QUB ARPM state table – receiver transactions.70

– 4 – 61158-6-9 © IEC:2010(E)
Table 18 – BNU ARPM states .76
Table 19 – BNU ARPM state table – sender transactions.77
Table 20 – BNU ARPM state table – receiver transactions .78
Table 21 – Primitives issued from ARPM to DMPM .81
Table 22 – Primitives issued by DMPM to ARPM .81
Table 23 – Parameters used with primitives exchanged between ARPM and DMPM .82
Table 24 – Function GetArepId().83
Table 25 – Function BuildFAS-PDU .83
Table 26 – Function FAS_Pdu_Type.83
Table 27 – Function AbortIdentifier .83
Table 28 – Function AbortReason.83
Table 29 – Function AbortDetail.84
Table 30 – DMPM state descriptions.84
Table 31 – DMPM state table – sender transactions .85
Table 32 – DMPM state table – receiver transactions.87
Table 33 – Primitives exchanged between data-link layer and DMPM .92
Table 34 – Function PickArep .94
Table 35 – Function FindAREP .95
Table 36 – Function LocateQubArep .95
Table 37 – Function SetIdentifier().95

61158-6-9 © IEC:2010(E) – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
INDUSTRIAL COMMUNICATION NETWORKS –
FIELDBUS SPECIFICATIONS –
Part 6-9: Application layer protocol specification –
Type 9 elements
FOREWORD
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
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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.
NOTE 1 Use of some of the associated protocol types is restricted by their intellectual-property-right holders. In
all cases, the commitment to limited release of intellectual-property-rights made by the holders of those rights
permits a particular data-link layer protocol type to be used with physical layer and application layer protocols in
Type combinations as specified explicitly in the profile parts. Use of the various protocol types in other
combinations may require permission from their respective intellectual-property-right holders.
International Standard IEC 61158-6-9 has been prepared by subcommittee 65C: Industrial
networks, of IEC technical committee 65: Industrial-process measurement, control and
automation.
This second edition cancels and replaces the first edition published in 2007. This edition
constitutes a technical revision.
The main change with respect to the previous edition is listed below:

– 6 – 61158-6-9 © IEC:2010(E)
• Correction of Table 32.
The text of this standard is based on the following documents:
FDIS Report on voting
65C/607/FDIS 65C/621/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with ISO/IEC Directives, Part 2.
A list of all parts of the IEC 61158 series, published under the general title Industrial
communication networks – Fieldbus specifications, can be found on the IEC web site.
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be:
• reconfirmed;
• withdrawn;
• replaced by a revised edition, or
• amended.
NOTE 2 The revision of this standard will be synchronized with the other parts of the IEC 61158 series.

61158-6-9 © IEC:2010(E) – 7 –
INTRODUCTION
This part of IEC 61158 is one of a series produced to facilitate the interconnection of
automation system components. It is related to other standards in the set as defined by the
“three-layer” fieldbus reference model described in IEC/TR 61158-1.
The application protocol provides the application service by making use of the services
available from the data-link or other immediately lower layer. The primary aim of this standard
is to provide a set of rules for communication expressed in terms of the procedures to be
carried out by peer application entities (AEs) at the time of communication. These rules for
communication are intended to provide a sound basis for development in order to serve a
variety of purposes:
• as a guide for implementors and designers;
• for use in the testing and procurement of equipment;
• as part of an agreement for the admittance of systems into the open systems environment;
• as a refinement to the understanding of time-critical communications within OSI.
This standard is concerned, in particular, with the communication and interworking of sensors,
effectors and other automation devices. By using this standard together with other standards
positioned within the OSI or fieldbus reference models, otherwise incompatible systems may
work together in any combination.

– 8 – 61158-6-9 © IEC:2010(E)
INDUSTRIAL COMMUNICATION NETWORKS –
FIELDBUS SPECIFICATIONS –
Part 6-9: Application layer protocol specification –
Type 9 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 9 fieldbus. The term “time-critical” is used to represent the presence
of a time-window, within which one or more specified actions are required to be completed
with some defined level of certainty. Failure to complete specified actions within the time
window risks failure of the applications requesting the actions, with attendant risk to
equipment, plant and possibly human life.
This standard defines in an abstract way the externally visible behavior provided by the Type
9 fieldbus Application Layer in terms of
a) the abstract syntax defining the application layer protocol data units conveyed between
communicating application entities,
b) the transfer syntax defining the application layer protocol data units conveyed between
communicating application entities,
c) the application context state machine defining the application service behavior visible
between communicating application entities; and
d) the application relationship state machines defining the communication behavior visible
between communicating application entities; and.
The purpose of this standard is to define the protocol provided to
1) define the wire-representation of the service primitives defined in IEC 61158-5-5, and
2) define the externally visible behavior associated with their transfer.
This standard specifies the protocol of the Type 9 IEC fieldbus application layer, in
conformance with the OSI Basic Reference Model (ISO/IEC 7498) and the OSI Application
Layer Structure (ISO/IEC 9545).
1.2 Specifications
The principal objective of this standard is to specify the syntax and behavior of the application
layer protocol that conveys the application layer services defined in IEC 61158-5-9.
A secondary objective is to provide migration paths from previously-existing industrial
communications protocols. It is this latter objective which gives rise to the diversity of
protocols standardized in IEC 61158-6.

61158-6-9 © IEC:2010(E) – 9 –
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.
Conformance is achieved through implementation of this application layer protocol
specification.
2 Normative references
The following referenced documents are indispensable for the application of this document.
For dated references, only the edition cited applies. For undated references, the latest edition
of the referenced document (including any amendments) applies.
IEC 60559, Binary floating-point arithmetic for microprocessor systems
IEC 61158-3-1, Industrial communication networks – Fieldbus specifications – Part 3-1: Data-
link layer service definition – Type 1 elements
IEC 61158-4-1, Industrial communication networks – Fieldbus specifications – Part 4-1: Data-
link layer protocol specification – Type 1 elements
IEC 61158-5-5, Industrial communication networks – Fieldbus specifications – Part 5-5:
Application layer service definition – Type 5 elements
IEC 61158-5-9, Industrial communication networks – Fieldbus specifications – Part 5-9:
Application layer service definition – Type 9 elements
ISO/IEC 7498-1, Information technology – Open Systems Interconnection – Basic Reference
Model: The Basic Model
ISO/IEC 8824-1, Information technology – Abstract Syntax Notation One (ASN.1):
Specification of basic notation
ISO/IEC 8825-1, Information technology -- ASN.1 encoding rules: Specification of Basic
Encoding Rules (BER), Canonical Encoding Rules (CER) and Distinguished Encoding Rules
(DER)
ISO/IEC 9545, Information technology – Open Systems Interconnection – Application Layer
structure
ISO/IEC 10731, Information technology – Open Systems Interconnection – Basic Reference
Model – Conventions for the definition of OSI services
3 Terms, definitions, symbols, abbreviations and conventions
For the purposes of this document, the following terms and definitions apply.
3.1 Terms and definitions from other ISO/IEC standards
3.1.1 Terms and definitions from ISO/IEC 7498-1
a) abstract syntax
b) application entity
c) application process
d) application protocol data unit
e) application service element
f) application entity invocation

– 10 – 61158-6-9 © IEC:2010(E)
g) application process invocation
h) application transaction
i) presentation context
j) real open system
k) transfer syntax
3.1.2 Terms and definitions from ISO/IEC 9545
a) application-association
b) application-context
c) application context name
d) application-entity-invocation
e) application-entity-type
f) application-process-invocation
g) application-process-type
h) application-service-element
i) application control service element
3.1.3 Terms and definitions from ISO/IEC 8824-1
a) object identifier
b) type
c) value
d) simple type
e) structured type
f) component type
g) tag
h) Boolean type
i) true
j) false
k) integer type
l) bitstring type
m) octetstring type
n) null type
o) sequence type
p) sequence of type
q) choice type
r) tagged type
s) any type
t) module
u) production
3.1.4 Terms and definitions from ISO/IEC 8825-1
a) encoding (of a data value)
b) data value
c) identifier octets (the singular form is used in this standard)
d) length octet(s) (both singular and plural forms are used in this standard)
e) contents octets
3.2 IEC/TR 61158-1 terms
The following IEC/TR 61158-1 terms apply.
3.2.1 application
function or data structure for which data is consumed or produced
3.2.2 application layer interoperability
capability of application entities to perform coordinated and cooperative operations using the
services of the FAL
61158-6-9 © IEC:2010(E) – 11 –
3.2.3 application object
object class that manages and provides the run time exchange of messages across the
network and within the network device
NOTE: Multiple types of application object classes may be defined
3.2.4 application process
part of a distributed application on a network, which is located on one device and
unambiguously addressed
3.2.5 application process identifier
distinguishes multiple application processes used in a device
3.2.6 application process object
component of an application process that is identifiable and accessible through an FAL
application relationship. Application process object definitions are composed of a set of
values for the attributes of their class (see the definition for Application Process Object Class
Definition). Application process object definitions may be accessed remotely using the
services of the FAL Object Management ASE. FAL Object Management services can be used
to load or update object definitions, to read object definitions, and to dynamically create and
delete application objects and their corresponding definitions
3.2.7 application process object class
a class of application process objects defined in terms of the set of their network-accessible
attributes and services
3.2.8 application relationship
cooperative association between two or more application-entity-invocations for the purpose of
exchange of information and coordination of their joint operation. This relationship is activated
either by the exchange of application-protocol-data-units or as a result of preconfiguration
activities
3.2.9 application relationship application service element
application-service-element that provides the exclusive means for establishing and
terminating all application relationships
3.2.10 application relationship endpoint
context and behavior of an application relationship as seen and maintained by one of the
application processes involved in the application relationship. Each application process
involved in the application relationship maintains its own application relationship endpoint
3.2.11 attribute
description of an externally visible characteristic or feature of an object. The attributes of an
object contain information about variable portions of an object. Typically, they provide status
information or govern the operation of an object. Attributes may also affect the behaviour of
an object. Attributes are divided into class attributes and instance attributes
3.2.12 behaviour
indication of how the object responds to particular events. Its description includes the
relationship between attribute values and services

– 12 – 61158-6-9 © IEC:2010(E)
3.2.13 class
a set of objects, all of which represent the same kind of system component. A class is a
generalisation of the object; a template for defining variables and methods. All objects in a
class are identical in form and behaviour, but usually contain different data in their attributes
3.2.14 class attributes
an attribute that is shared by all objects within the same class
3.2.15 class code
a unique identifier assigned to each object class
3.2.16 class specific service
a service defined by a particular object class to perform a required function which is not
performed by a common service. A class specific object is unique to the object class which
defines it
3.2.17 client
(a) an object which uses the services of another (server) object to perform a task
(b) an initiator of a message to which a server reacts, such as the role of an AR endpoint in
which it issues confirmed service request APDUs to a single AR endpoint acting as a server
3.2.18 conveyance path
unidirectional flow of APDUs across an application relationship
3.2.19 cyclic
term used to describe events which repeat in a regular and repetitive manner
3.2.20 dedicated AR
AR used directly by the FAL User. On Dedicated ARs, only the FAL Header and the user data
are transferred
3.2.21 device
a physical hardware connection to the link. A device may contain more than one node
3.2.22 device profile
a collection of device dependent information and functionality providing consistency between
similar devices of the same device type
3.2.23 dynamic AR
AR that requires the use of the AR establishment procedures to place it into an established
state
3.2.24 endpoint
one of the communicating entities involved in a connection

61158-6-9 © IEC:2010(E) – 13 –
3.2.25 error
a discrepancy between a computed, observed or measured value or condition and the
specified or theoretically correct value or condition
3.2.26 error class
general grouping for error definitions. Error codes for specific errors are defined within an
error class
3.2.27 error code
identification of a specific type of error within an error class
3.2.28 FAL subnet
networks composed of one or more data link segments. They are permitted to contain bridges,
but not routers. FAL subnets are identified by a subset of the network address
3.2.29 logical device
specifies a certain FAL class that abstracts a software component or a firmware component
as an autonomous self-contained facility of an automation device
3.2.30 management information
network-accessible information that supports managing the operation of the fieldbus system,
including the application layer. Managing includes functions such as controlling, monitoring,
and diagnosing
3.2.31 network
a series of nodes connected by some type of communication medium. The connection paths
between any pair of nodes can include repeaters, routers and gateways
3.2.32 peer
role of an AR endpoint in which it is capable of acting as both client and server
3.2.33 pre-defined AR endpoint
AR endpoint that is defined locally within a device without use of the create service. Pre-
defined ARs that are not pre-established are established before being used
3.2.34 pre-established AR endpoint
AR endpoint that is placed in an established state during configuration of the AEs that control
its endpoints
3.2.35 publisher
role of an AR endpoint in which it transmits APDUs onto the fieldbus for consumption by one
or more subscribers. The publisher may not be aware of the identity or the number of
subscribers and it may publish its APDUs using a dedicated AR. Two types of publishers are
defined by this standard, Pull Publishers and Push Publishers, each of which is defined
separately
– 14 – 61158-6-9 © IEC:2010(E)
3.2.36 server
a) role of an AREP in which it returns a confirmed service response APDU to the client that
initiated the request
b) an object which provides services to another (client) object
3.2.37 service
operation or function than an object and/or object class performs upon request from another
object and/or object class. A set of common services is defined and provisions for the
definition of object-specific services are provided. Object-specific services are those which
are defined by a particular object class to perform a required function which is not performed
by a common service
3.2.38 subscriber
role of an AREP in which it receives APDUs produced by a publisher. Two types of
subscribers are defined by this standard, pull subscribers and push subscribers, each of
which is defined separately
3.3 Abbreviations and symbols
AE Application Entity
AL Application Layer
ALME Application Layer Management Entity
ALP Application Layer Protocol
APO Application Object
AP Application Process
APDU Application Protocol Data Unit
API Application Process Identifier
AR Application Relationship
AREP Application Relationship End Point
ASCII American Standard Code for Information Interchange
ASE Application service Element
Cnf Confirmation
DL- (as a prefix) data-link-
DLC Data-link Connection
DLCEP Data-link Connection End Point
DLL Data-link layer
DLM Data-link-management
DLSAP Data-link service Access Point
DLSDU DL-service-data-unit
FAL Fieldbus Application Layer
ID Identifier
IEC International Electrotechnical Commission
Ind Indication
61158-6-9 © IEC:2010(E) – 15 –
LME Layer Management Entity
OSI Open Systems Interconnect
QoS Quality of service
Req Request
Rsp Response
SAP Service Access Point
SDU Service Data Unit
SMIB System Management Information Base
SMK System Management Kernel
VFD Virtual Field Device
3.4 Conventions
3.4.1 General concept
The FAL is defined as a set of object-oriented ASEs. Each ASE is specified in a separate
subclause. Each ASE specification is composed of three parts: its class definitions, its
services, and its protocol specification. The first two are contained in IEC 61158-5 subseries.
The protocol specification for each of the ASEs is defined in this standard.
The class definitions define the attributes of the classes supported by each ASE. The
attributes are accessible from instances of the class using the Management ASE services
specified in IEC 61158-5 standard. The service specification defines the services that are
provided by the ASE.
This standard uses the descriptive conventions given in ISO/IEC 10731.
3.4.2 Conventions for class definitions
The data-link layer mapping definitions are described using templates. Each template consists
of a list of attributes for the class. The general form of the template is defined in IEC 61158-5-
5.
3.4.3 Abstract syntax conventions
When the "optionalParametersMap" parameter is used, a bit number which corresponds to
each OPTIONAL or DEFAULT production is given as a comment.
3.5 Conventions used in state machines
The state machines are described in Table 1:
Table 1 – Conventions used for state machines
Event
Current
# / condition Next state
state
=> action
Name of The Events or conditions that trigger this state transaction. The next
this current state after
=>
transition. state to the actions
which this in this
The actions that are taken when the above events or
state transition is
conditions are met. The actions are always indented below
transition taken.
events or conditions.
applies.
The conventions used in the state machines are as follows:

– 16 – 61158-6-9 © IEC:2010(E)
:= Value of an item on the left is replaced by value of an item on the right. If an item on the
right is a parameter, it comes from the primitive shown as an input event.
xxx A parameter name.
Example:
Identifier := reason
means value of a 'reason' parameter is assigned to a parameter called 'Identifier.'
"xxx" Indicates fixed value.
Example:
Identifier := "abc"
means value "abc" is assigned to a parameter named 'Identifier.'

= A logical condition to indicate an item on the left is equal to an item on the right.
< A logical condition to indicate an item on the left is less than the item on the right.
> A logical condition to indicate an item on the left is greater than the item on the right.
<> A logical condition to indicate an item on the left is not equal to an item on the right.
&& Logical "AND"
|| Logical "OR"
This construct allows the execution of a sequence of actions in a loop within one transition.
The loop is executed for all values from start_value to end_value.
Example:
for (Identifier := start_value to end_value)
actions
endfor
This construct allows the execution of alternative actions depending on some condition (which
might be the value of some identifier or the outcome of a previous action) within one transition.
Example:
If (condition)
actions
else
actions
endif
Readers are strongly recommended to refer to the subclauses for the AREP attribute
definitions, the local functions, and the FAL-PDU definitions to understand protocol machines.
It is assumed that readers have sufficient knowledge of these definitions, and they are used
without further explanations.
4 Abstract syntax
4.1 FAL-AR PDU abstract syntax
4.1.1 Top level definition
The productions defined here shall be used with the rules for APDU encoding (see 5. 1. 2) .

61158-6-9 © IEC:2010(E) – 17 –
APDU ::= CHOICE {
[PRIVATE 0] ConfirmedSend-RequestPDU,
[PRIVATE 1] ConfirmedSend-ResponsePDU,
[PRIVATE 2] UnconfirmedSend-PDU,
[PRIVATE 3] UnconfirmedAcknowledgedSend-CommandPDU,
[PRIVATE 4] Establish-RequestPDU,
[PRIVATE 5] Establish-ResponsePDU,
[PRIVATE 6] Establish-ErrorPDU,
[PRIVATE 7] Abort-PDU,
[PRIVATE 8] DataSendAcknowledge-PDU
}
4.1.2 Confirmed send service
ConfirmedSend-RequestPDU ::= SEQUENCE {
[APPLICATION 0] AddressAREP,
InvokeID,
ConfirmedServiceRequest
}
ConfirmedSend-ResponsePDU ::= SEQUENCE {
[APPLICATION 1] AddressAREP,
InvokeID,
pduBody CHOICE {
ConfirmedServiceResponse,
ConfirmedServiceError
}
}
4.1.3 Unconfirmed send service
UnconfirmedSend-PDU ::= SEQUENCE {
[APPLICATION 2] AddressAREP,
InvokeID,
pduBody CHOICE {
UnconfirmedServiceRequest,
UnconfirmedSendPD-PDU
}
}
4.1.4 Unconfirmed acknowledge send service
UnconfirmedAcknowledgeSend-CommandPDU ::= SEQUENCE {
[APPLICATION 3] AddressAREP,
InvokeID,
UnconfirmedServiceRequest
}
4.1.5 InvokeID
InvokeID ::= Unsigned8
4.1.6 Establish service
MaxOSCC ::= Unsigned8
MaxOSCS ::= Unsigned8
MaxUCSC ::= Unsigned8
MaxUCSS ::= Unsigned8
CIU ::= Unsigned32
Establish-RequestPDU ::= SEQUENCE {
[APPLICATION 4] AddressAREP,
ConType,
MaxOSCC,
MaxOSCS,
MAXUCSC,
MAXUCSS,
CIU,
InvokeID,
initiateRequest [PRIVATE 0] IMPLICIT Initiate-RequestPDU
}
– 18 – 61158-6-9 © IEC:2010(E)
Establish-ResponsePDU ::= SEQUENCE {
[APPLICATION 5] AddressAREP,
InvokeID,
initiateResponse [PRIVATE 0] IMPLICIT Initiate-ResponsePDU
}
Establish-ErrorPDU ::= SEQUENCE {
[APPLICATION 6] AddressAREP,
InvokeID,
initiateError  [PRIVATE 0] IMPLICIT Initiate-ErrorPDU
}
4.1.7 ConType
ConType ::= ENUMERATED {
mmaz (0)
}
4.1.8 Data send acknowledge service
DataSendAcknowledge-PDU ::= SEQUENCE {
Protocol-Code,[APPLICATION 8],Address2ARP,  --- Protocol-Code in the higher nibble of the
octet!!!
Block-Number,
Block-Length,
Protocol-Data,
}
4.1.9 Protocol-code
Protocol-Code ::= ENUMERATED {
TCP/IP (1)  --- TCP/IP protocol
}
4.1.10 Block-number
Block-Number ::= Unsigned8  --- 0 no blocking
---- 1.254 block number
---- 255 last block
4.1.11 Block-length
Block-Length ::= Unsigned
4.1.12 Protocol-data
Protocol-Data::= Any  --- transparent protocol transfer

4.1.13 Address2 ARP
Address2ARP ::= SEQUENCE {
Destination-Address,
Source-Address,
Destination-Node,
Destination-Subnode,
Source-Node,
Source-Subnode
}
4.1.14 Destination-address
Destination-Address ::= OctetString   --- 3 Octets

4.1.15 Source-address
Source-Address ::= OctetString   --- 3 Octets

4.1.16 Destination-node
Destination-Node ::= Unsigned8

61158-6-9 © IEC:2010(E) – 19 –
4.1.17 Source-node
Source-Node ::= Unsigned8
4.1.18 Destination-subnode
Destination-Subnode ::= Unsigned8

4.1.19 Source-subnode
Source-Subnode ::= Unsigned8
4.2 Abstract syntax of PDUBody
4.2.1 Abort service
Abort-PDU ::= SEQUENCE {
[APPLICATION 7
...