IEC 61158-6-12:2010

IEC 61158-6-12 ®
Edition 2.0 2010-08
INTERNATIONAL
STANDARD
Industrial communication networks – Fieldbus specifications –
Part 6-12: Application layer protocol specification – Type 12 elements

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IEC 61158-6-12 ®
Edition 2.0 2010-08
INTERNATIONAL
STANDARD
Industrial communication networks – Fieldbus specifications –
Part 6-12: Application layer protocol specification – Type 12 elements

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
XG
ICS 25.04.40; 35.100.70; 35.110 ISBN 978-2-88912-129-8
– 2 – 61158-6-12 © IEC:2010(E)
CONTENTS
FOREWORD.5H7
INTRODUCTION.6H9
1 Scope.7H10
1.1 General .8H10
1.2 Specifications .9H11
1.3 Conformance.10H11
2 Normative references.11H11
3 Terms, definitions, symbols, abbreviations and conventions .12H12
3.1 Reference model terms and definitions .13H12
3.2 Service convention terms and definitions .14H12
3.3 Application layer definitions.15H13
3.4 Common symbols and abbreviations .16H18
3.5 Additional symbols and abbreviations.17H18
3.6 Conventions .18H20
4 Application layer protocol specification.19H25
4.1 Operating principle .20H25
4.2 Node reference model .21H25
5 FAL syntax description.22H27
5.1 Coding principles .23H27
5.2 Data types and encoding rules .24H27
5.3 AR coding.25H30
5.4 SII coding .26H35
5.5 Isochronous PDI coding.27H40
5.6 CoE coding.28H44
5.7 EoE coding.29H82
5.8 FoE Coding .30H91
6 FAL protocol state machines.31H97
6.1 Overall structure .32H97
6.2 AP-Context state machine .33H99
6.3 FAL service protocol machine (FSPM) .34H99
6.4 Application Relationship Protocol Machines (ARPMs).35H99
6.5 DLL mapping protocol machine (DMPM) .36H142
Bibliography .37H143

Figure 1 – Common structure of specific fields .38H20
Figure 2 – Type description example .39H22
Figure 3 – Slave Node Reference Model.40H26
Figure 4 – Encoding of Time Of Day value.41H27
Figure 5 – Encoding of Time Difference value.42H28
Figure 6 – AL Control Request structure.43H30
Figure 7 – AL Control Response structure .44H31
Figure 8 – AL State Changed structure .45H33
Figure 9 – PDI Control type description .46H34
Figure 10 – Sync Configuration type description .47H34

61158-6-12 © IEC:2010(E) – 3 –
Figure 11 – Distributed Clock sync and latch type description .48H41
Figure 12 – CoE general structure .49H44
Figure 13 – SDO Download Expedited Request structure.50H45
Figure 14 – SDO Download Expedited Response structure .51H46
Figure 15 – SDO Download Normal Request structure.52H47
Figure 16 – Download SDO Segment Request structure .53H49
Figure 17 – Download SDO Segment Response structure.54H50
Figure 18 – SDO Upload Expedited Request structure .55H50
Figure 19 – SDO Upload Expedited Response structure .56H51
Figure 20 – SDO Upload Normal Response structure.57H53
Figure 21 – Upload SDO Segment Request structure.58H54
Figure 22 – Upload SDO Segment Response structure .59H54
Figure 23 – Abort SDO Transfer Request structure.60H55
Figure 24 – SDO Information Service structure.61H58
Figure 25 – Get OD List Request structure .62H58
Figure 26 – Get OD List Response structure.63H59
Figure 27 – Get Object Description Request structure.64H61
Figure 28 – Get Object Description Response structure.65H61
Figure 29 – Get Entry Description Request structure.66H62
Figure 30 – Get Entry Description Response structure .67H63
Figure 31 – SDO Info Error Request structure .68H65
Figure 32 – EoE general structure .69H82
Figure 33 – EoE Timestamp structure.70H83
Figure 34 – EoE Fragment Request structure .71H84
Figure 35 – Set IP Parameter Request structure.72H86
Figure 36 – Set IP Parameter Response structure .73H88
Figure 37 – Set Address Filter Request structure.74H89
Figure 38 – Set Address Filter Response structure .75H91
Figure 39 – Read Request structure .76H92
Figure 40 – Write Request structure .77H92
Figure 41 – Data Request structure .78H93
Figure 42 – Ack Request structure .79H94
Figure 43 – Error Request structure.80H95
Figure 44 – Busy Request structure.81H97
Figure 45 – Relationship among Protocol Machines .82H98
Figure 46 – AR Protocol machines .83H99
Figure 47 – ESM Diagramm .84H101

Table 1 – PDU element description example.85H22
Table 2 – Example attribute description .86H23
Table 3 – State machine description elements .87H23
Table 4 – Description of state machine elements .88H24
Table 5 – Conventions used in state machines .89H24

– 4 – 61158-6-12 © IEC:2010(E)
Table 6 – Transfer Syntax for bit sequences.90H28
Table 7 – Transfer syntax for data type Unsignedn .91H29
Table 8 – Transfer syntax for data type Integern.92H30
Table 9 – AL Control Description .93H31
Table 10 – AL Control Response .94H31
Table 11 – AL Status Codes .95H32
Table 12 – AL State Changed.96H33
Table 13 – PDI Control.97H34
Table 14 – PDI Configuration .98H34
Table 15 – Sync Configuration.99H35
Table 16 – Slave Information Interface Area .100H35
Table 17 – Slave Information Interface Categories.101H36
Table 18 – Mailbox Protocols Supported Types .102H36
Table 19 – Categories Types.103H37
Table 20 – Structure Category String.104H37
Table 21 – Structure Category General.105H38
Table 22 – Structure Category FMMU.106H39
Table 23 – Structure Category SyncM for each Element.107H39
Table 24 – Structure Category TXPDO and RXPDO for each PDO.108H40
Table 25 – Structure PDO Entry .109H40
Table 26 – Distributed Clock sync parameter.110H42
Table 27 – Distributed Clock latch data .111H43
Table 28 – CoE elements .112H44
Table 29 – SDO Download Expedited Request .113H46
Table 30 – SDO Download Expedited Response.114H47
Table 31 – SDO Download Normal Request.115H48
Table 32 – Download SDO Segment Request .116H49
Table 33 – Download SDO Segment Response .117H50
Table 34 – SDO Upload Expedited Request.118H51
Table 35 – SDO Upload Expedited Response .119H52
Table 36 – SDO Upload Normal Response .120H53
Table 37 – Upload SDO Segment Request .121H54
Table 38 – Upload SDO Segment Response.122H55
Table 39 – Abort SDO Transfer Request .123H56
Table 40 – SDO Abort Codes .124H57
Table 41 – SDO Information Service.125H58
Table 42 – Get OD List Request.126H59
Table 43 – Get OD List Response .127H60
Table 44 – Get Object Description Request .128H61
Table 45 – Get Object Description Response.129H62
Table 46 – Get Entry Description Request .130H63
Table 47 – Get Entry Description Response.131H64
Table 48 – SDO Info Error Request .132H66

61158-6-12 © IEC:2010(E) – 5 –
Table 49 – Emergency Request.133H67
Table 50 – Emergency Error Codes .134H68
Table 51 – Error Code.135H68
Table 52 – Diagnostic Data .136H69
Table 53 – Sync Manager Length Error.137H69
Table 54 – Sync Manager Address Error .138H69
Table 55 – Sync Manager Settings Error.139H69
Table 56 – RxPDO Transmission via mailbox .140H70
Table 57 – TxPDO Transmission via mailbox.141H70
Table 58 – RxPDO Remote Transmission Request .142H71
Table 59 – TxPDO Remote Transmission Request .143H71
Table 60 – Command object structure .144H72
Table 61 – Object Dictionary Structure .145H72
Table 62 – Object Code Definitions .146H72
Table 63 – Basic Data Type Area .147H73
Table 64 – Extended Data Type Area .148H74
Table 65 – Enumeration Definition.149H75
Table 66 – CoE Communication Area .150H75
Table 67 – Device Type.151H76
Table 68 – Error Register .152H77
Table 69 – Manufacturer Device Name.153H77
Table 70 – Manufacturer Hardware Version .154H78
Table 71 – Manufacturer Software Version .155H78
Table 72 – Identity Object.156H78
Table 73 – Receive PDO Mapping .157H79
Table 74 – Transmit PDO Mapping.158H79
Table 75 – Sync Manager Communication Type .159H80
Table 80 – Sync Manager Channel 0-31 .160H81
Table 81 – Sync Manager Synchronization .161H82
Table 82 – Initiate EoE Request .162H83
Table 83 – Initiate EoE Response.163H84
Table 84 – EoE Fragment Request.164H85
Table 85 – EoE Data .165H86
Table 86 – Set IP Parameter Request.166H87
Table 87 – Set IP Parameter Response.167H88
Table 88 – EoE Result Parameter .168H89
Table 89 – Set Address Filter Request .169H90
Table 90 – Set Address Filter Response.170H91
Table 91 – Read Request.171H92
Table 92 – Write Request.172H93
Table 93 – Data Request.173H94
Table 94 – Ack Request .174H95
Table 95 – Error Request .175H96

– 6 – 61158-6-12 © IEC:2010(E)
Table 96 – Error codes of FoE.176H96
Table 97 – Busy Request .177H97
Table 98 – State transitions and local management services .178H101
Table 99 – Primitives issued by ESM to DL.179H102
Table 100 – Primitives issued by DL to ESM.180H102
Table 101 – Primitives issued by Application to ESM .181H103
Table 102 – Primitives issued by ESM to Application .182H103
Table 103 – ESM Variables .183H103
Table 104 – ESM macros .184H104
Table 105 – ESM functions.185H105
Table 106 – ESM state table .186H106
Table 107 – ESM Functions.187H118
Table 108 – Primitives issued by Mailbox handler to DL.188H118
Table 109 – Primitives issued by DL to Mailbox handler.189H118
Table 110 – Primitives issued by Protocol handler to Mailbox handler .190H119
Table 111 – Primitives issued by Mailbox handler to Protocol handler .191H119
Table 112 – Primitives issued by Application to CoESM .192H120
Table 113 – Primitives issued by CoESM to Application .193H121
Table 114 – CoESM state table .194H121
Table 115 – Primitives issued by Application to EoESM .195H131
Table 116 – Primitives issued by EoESM to Application .196H132
Table 117 – EoESM state table .197H133
Table 118 – Primitives issued by Application to FoESM .198H137
Table 119 – Primitives issued by FoESM to Application .199H138
Table 120 – FoESM state table.200H138

61158-6-12 © IEC:2010(E) – 7 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
INDUSTRIAL COMMUNICATION NETWORKS –
FIELDBUS SPECIFICATIONS –
Part 6-12: Application layer protocol specification –
Type 12 elements
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
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2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
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3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
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4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
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between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
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 of their respective intellectual-property-right holders.
International Standard IEC 61158-6-12 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 changes with respect to the previous edition are listed below:

– 8 – 61158-6-12 © IEC:2010(E)
a) bug fixes; and
b) editorial improvements.
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.

61158-6-12 © IEC:2010(E) – 9 –
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.

– 10 – 61158-6-12 © IEC:2010(E)
INDUSTRIAL COMMUNICATION NETWORKS –
FIELDBUS SPECIFICATIONS –
Part 6-12: Application layer protocol specification –
Type 12 elements
1 Scope
1.1 General
The Fieldbus Application Layer (FAL) provides user programs with a means to access the
fieldbus communication environment. In this respect, the FAL can be viewed as a “window
between corresponding application programs.”
This standard provides common elements for basic time-critical and non-time-critical
messaging communications between application programs in an automation environment and
material specific to Type 12 fieldbus. The term “time-critical” is used to represent the presence
of a time-window, within which one or more specified actions are required to be completed with
some defined level of certainty. Failure to complete specified actions within the time window
risks failure of the applications requesting the actions, with attendant risk to equipment, plant
and possibly human life.
This standard defines in an abstract way the externally visible behavior provided by the
different Types of the fieldbus Application Layer in terms of
a) the abstract syntax defining the application layer protocol data units conveyed between
communicating application entities,
b) the transfer syntax defining the application layer protocol data units conveyed between
communicating application entities,
c) the application context state machine defining the application service behavior visible
between communicating application entities; and
d) the application relationship state machines defining the communication behavior visible
between communicating application entities; and.
The purpose of this standard is to define the protocol provided to
a) define the wire-representation of the service primitives defined in IEC 61158-5-12, and
b) define the externally visible behavior associated with their transfer.
This standard specifies the protocol of the IEC fieldbus Application Layer, in conformance with
the OSI Basic Reference Model (ISO/IEC 7498) and the OSI Application Layer Structure
(ISO/IEC 9545).
FAL services and protocols are provided by FAL application-entities (AE) contained within the
application processes. The FAL AE is composed of a set of object-oriented Application Service
Elements (ASEs) and a Layer Management Entity (LME) that manages the AE. The ASEs
provide communication services that operate on a set of related application process object
(APO) classes. One of the FAL ASEs is a management ASE that provides a common set of
services for the management of the instances of FAL classes.
Although these services specify, from the perspective of applications, how request and
responses are issued and delivered, they do not include a specification of what the requesting
and responding applications are to do with them. That is, the behavioral aspects of the
applications are not specified; only a definition of what requests and responses they can

61158-6-12 © IEC:2010(E) – 11 –
send/receive is specified. This permits greater flexibility to the FAL users in standardizing such
object behavior. In addition to these services, some supporting services are also defined in this
standard to provide access to the FAL to control certain aspects of its operation.
1.2 Specifications
The principal objective of this standard is to specify the syntax and behavior of the application
layer protocol that conveys the application layer services defined in IEC 61158-5-12.
A secondary objective is to provide migration paths from previously-existing industrial
communications protocols. It is this latter objective which gives rise to the diversity of protocols
standardized in subparts of IEC 61158-6.
1.3 Conformance
This standard does not specify individual implementations or products, nor does it constrain the
implementations of application layer entities within industrial automation systems.
There is no conformance of equipment to the application layer service definition standard.
Instead, conformance is achieved through implementation of this application layer protocol
specification.
2 Normative references
The following 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 61158-3-12, Industrial communication networks – Fieldbus specifications – Part 3-12:
Data-link layer service definition – Type 12 elements
IEC 61158-5-12, Industrial communication networks – Fieldbus specifications – Part 5-12:
Application layer service definition – Type 12 elements
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 8802-3, Information technology – Telecommunications and information exchange
between systems - Local and metropolitan area networks – Specific requirements – Part 3:
Carrier sense multiple access with collision detection (CSMA/CD) access method and physical
layer specifications
ISO/IEC 9545, Information technology – Open Systems Interconnection – Application Layer
structure
ISO/IEC 9899, Programming Languages – C
ISO/IEC 10731, Information technology – Open Systems Interconnection – Basic Reference
Model – Conventions for the definition of OSI services

– 12 – 61158-6-12 © IEC:2010(E)
IEEE 802.1D-2004, IEEE standard for Local and metropolitan area networks – Common
specifications – Media access control (MAC) Bridges; available at <0Hhttp://www.ieee.org>
IEEE 802.1Q-1998, IEEE standard for Local and metropolitan area networks – Virtual bridged
local area networks Bridges; available at <1Hhttp://www.ieee.org>
IETF RFC 768, User Datagram Protocol; available at <2Hhttp://www.ietf.org>
IETF RFC 791, Internet Protocol darpa internet program protocol specification; available at
<3Hhttp://www.ietf.org>
3 Terms, definitions, symbols, abbreviations and conventions
For the purposes of this document, the following terms, definitions, symbols, abbreviations and
conventions apply.
3.1 Reference model terms and definitions
This standard is based in part on the concepts developed in ISO/IEC 7498-1 and
ISO/IEC 7498-3, and makes use of the following terms defined therein:
3.1.1 correspondent (N)-entities [ISO/IEC 7498-1]
correspondent AL-entities  (N=7)
3.1.2 (N)-entity [ISO/IEC 7498-1]
AL-entity  (N=7)
3.1.3 (N)-layer [ISO/IEC 7498-1]
AL-layer  (N=7)
[ISO/IEC 7498-1]
3.1.4 layer-management
[ISO/IEC 7498-1]
3.1.5 peer-entities
[ISO/IEC 7498-3]
3.1.6 primitive name
[ISO/IEC 7498-1]
3.1.7 AL-protocol
3.1.8 AL-protocol-data-unit [ISO/IEC 7498-1]
3.1.9 reset [ISO/IEC 7498-1]
3.1.10 routing [ISO/IEC 7498-1]
3.1.11 segmenting [ISO/IEC 7498-1]
3.1.12 (N)-service [ISO/IEC 7498-1]
AL-service  (N=7)
3.1.13 AL-service-data-unit [ISO/IEC 7498-1]
3.1.14 AL-simplex-transmission [ISO/IEC 7498-1]
[ISO/IEC 7498-1]
3.1.15 AL-subsystem
[ISO/IEC 7498-1]
3.1.16 systems-management
[ISO/IEC 7498-1]
3.1.17 AL-user-data
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:
61158-6-12 © IEC:2010(E) – 13 –
3.2.1 acceptor
3.2.2 asymmetrical service
3.2.3 confirm (primitive);
requestor.deliver (primitive)
3.2.4 deliver (primitive)
3.2.5 AL-service-primitive;
primitive
3.2.6 AL-service-provider
3.2.7 AL-service-user
3.2.8 indication (primitive);
acceptor.deliver (primitive)
3.2.9 request (primitive);
requestor.submit (primitive)
3.2.10 requestor
3.2.11 response (primitive);
acceptor.submit (primitive)
3.2.12 submit (primitive)
3.2.13 symmetrical service
3.3 Application layer definitions
3.3.1
application
function or data structure for which data is consumed or produced
3.3.2
application objects
multiple object classes that manage and provide a run time exchange of messages across the
network and within the network device
3.3.3
application process
part of a distributed application on a network, which is located on one device and
unambiguously addressed
3.3.4
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
3.3.5
attribute
description of an externally visible characteristic or feature of an object
NOTE 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 behavior of an object.
Attributes are divided into class attributes and instance attributes.
3.3.6
basic slave
slave device that supports only physical addressing of data

– 14 – 61158-6-12 © IEC:2010(E)
3.3.7
behavior
indication of how an object responds to particular events
3.3.8
bit
unit of information consisting of a 1 or a 0. This is the smallest data unit that can be
transmitted
3.3.9
channel
representation of a single physical or logical management object of a slave to control
conveyance of data
3.3.10
client
1) object which uses the services of another (server) object to perform a task
2) initiator of a message to which a server reacts
3.3.11
clock synchroization
representation of a sequence of interactions to synchronize the clocks of all time rece
...