IEC 61158-6-12:2007

IEC 61158-6-12
Edition 1.0 2007-12
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 1.0 2007-12
INTERNATIONAL
STANDARD
Industrial communication networks – Fieldbus specifications –
Part 6-12: Application layer protocol specification – Type 12 elements

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
XF
ICS 35.100.70; 25.040.40 ISBN 2-8318-9487-5

– 2 – 61158-6-12 © IEC:2007(E)

CONTENTS
FOREWORD.7

INTRODUCTION.9

1 Scope.10

1.1 General .10

1.2 Specifications .11

1.3 Conformance.11

2 Normative references.11

3 Terms, definitions, symbols, abbreviations and conventions .12
3.1 Reference model terms and definitions .12
3.2 Service convention terms and definitions .12
3.3 Application layer definitions.13
3.4 Common symbols and abbreviations .18
3.5 Additional symbols and abbreviations.18
3.6 Conventions .19
4 Application Layer protocol specification.24
4.1 Operating principle .24
4.2 Node reference model .24
5 FAL syntax description.26
5.1 Coding principles .26
5.2 Data types and encoding rules .26
5.3 AR coding.29
5.4 SII coding .34
5.5 Isochronous PDI coding.39
5.6 CoE coding.42
5.7 EoE coding.79
5.8 FoE Coding .88
6 FAL protocol state machines.94
6.1 Overall structure .94
6.2 AP-Context state machine .96
6.3 FAL service protocol machine (FSPM) .96
6.4 Application Relationship Protocol Machines (ARPMs).96
6.5 DLL mapping protocol machine (DMPM) . 135

Bibliography . 136

Figure 1 – Common structure of specific fields .20
Figure 2 – Type description example .21
Figure 3 – Slave Node Reference Model.25
Figure 4 – Encoding of Time Of Day value.26
Figure 5 – Encoding of Time Difference value.27
Figure 6 – AL Control Request structure.29
Figure 7 – AL Control Response structure .30
Figure 8 – AL State Changed structure .32
Figure 9 – PDI Control type description .32
Figure 10 – Sync Configuration type description .33

61158-6-12 © IEC:2007(E) – 3 –

Figure 11 – Distributed Clock sync and latch type description .39

Figure 12 – CoE general structure .42

Figure 13 – SDO Download Expedited Request structure.43

Figure 14 – SDO Download Expedited Response structure .44

Figure 15 – SDO Download Normal Request structure.45

Figure 17 – Download SDO Segment Request structure .47

Figure 18 – Download SDO Segment Response structure.47

Figure 19 – SDO Upload Expedited Request structure .48

Figure 20 – SDO Upload Expedited Response structure .49
Figure 22 – SDO Upload Normal Response structure.50
Figure 23 – Upload SDO Segment Request structure.51
Figure 24 – Upload SDO Segment Response structure .52
Figure 25 – Abort SDO Transfer Request structure.53
Figure 26 – SDO Information Service structure.55
Figure 27 – Get OD List Request structure .56
Figure 28 – Get OD List Response structure.57
Figure 29 – Get Object Description Request structure.58
Figure 30 – Get Object Description Response structure.59
Figure 31 – Get Entry Description Request structure.60
Figure 32 – Get Entry Description Response structure .61
Figure 33 – SDO Info Error Request structure .63
Figure 34 – EoE general structure .79
Figure 35 – EoE Timestamp structure.80
Figure 36 – EoE Fragment Request structure .81
Figure 37 – Set IP Parameter Request structure.83
Figure 38 – Set IP Parameter Response structure .85
Figure 39 – Set Address Filter Request structure.86
Figure 40 – Set Address Filter Response structure .88
Figure 41 – Read Request structure .89
Figure 42 – Write Request structure .89
Figure 43 – Data Request structure .90

Figure 44 – Ack Request structure .91
Figure 45 – Error Request structure.92
Figure 46 – Busy Request structure.94
Figure 47 – Relationship among Protocol Machines .95
Figure 48 – AR Protocol machines .96
Figure 49 – ESM Diagramm .98

Table 1 – PDU element description example.21
Table 2 – Example attribute description .22
Table 3 – State machine description elements .22
Table 4 – Description of state machine elements .23
Table 5 – Conventions used in state machines .23

– 4 – 61158-6-12 © IEC:2007(E)

Table 6 – Transfer Syntax for bit sequences.27

Table 7 – Transfer syntax for data type Unsignedn .28

Table 8 – Transfer syntax for data type Integern.29

Table 9 – AL Control Description .30

Table 10 – AL Control Response .30

Table 11 – AL Status Codes .31

Table 12 – AL State Changed.32

Table 13 – PDI Control.33

Table 14 – PDI Configuration .33
Table 15 – Sync Configuration.33
Table 16 – Slave Information Interface Area .34
Table 17 – Slave Information Interface Categories.35
Table 18 – Mailbox Protocols Supported Types .35
Table 19 – Categories Types.36
Table 20 – Structure Category String.36
Table 21 – Structure Category General.37
Table 22 – Structure Category FMMU.38
Table 23 – Structure Category SyncM for each Element.38
Table 24 – Structure Category TXPDO and RXPDO for each PDO.38
Table 25 – Structure PDO Entry .39
Table 26 – Distributed Clock sync parameter.40
Table 27 – Distributed Clock latch data .41
Table 28 – CoE elements .42
Table 29 – SDO Download Expedited Request .44
Table 30 – SDO Download Expedited Response.45
Table 31 – SDO Download Normal Request.46
Table 33 – Download SDO Segment Request .47
Table 34 – Download SDO Segment Response .48
Table 35 – SDO Upload Expedited Request.49
Table 36 – SDO Upload Expedited Response .50
Table 38 – SDO Upload Normal Response .51

Table 39 – Upload SDO Segment Request .52
Table 40 – Upload SDO Segment Response.53
Table 41 – Abort SDO Transfer Request .54
Table 42 – SDO Abort Codes .55
Table 43 – SDO Information Service.56
Table 44 – Get OD List Request.57
Table 45 – Get OD List Response .58
Table 46 – Get Object Description Request .59
Table 47 – Get Object Description Response.60
Table 48 – Get Entry Description Request .61
Table 49 – Get Entry Description Response.62
Table 50 – SDO Info Error Request .63

61158-6-12 © IEC:2007(E) – 5 –

Table 51 – Emergency Request.64

Table 52 – Emergency Error Codes .65

Table 53 – Error Code.65

Table 54 – Diagnostic Data .66

Table 55 – Sync Manager Length Error.66

Table 56 – Sync Manager Address Error .66

Table 57 – Sync Manager Settings Error.66

Table 58 – RxPDO Transmission via mailbox .67

Table 59 – TxPDO Transmission via mailbox.67
Table 60 – RxPDO Remote Transmission Request .68
Table 61 – TxPDO Remote Transmission Request .68
Table 62 – Command object structure .69
Table 63 – Object Dictionary Structure .69
Table 64 – Object Code Definitions .69
Table 65 – Basic Data Type Area .70
Table 66 – Extended Data Type Area .71
Table 67 – Enumeration Definition.72
Table 67 – CoE Communication Area .72
Table 68 – Device Type.73
Table 70 – Error Register .74
Table 69 – Manufacturer Device Name.74
Table 70 – Manufacturer Hardware Version .75
Table 71 – Manufacturer Software Version .75
Table 72 – Identity Object.75
Table 73 – Receive PDO Mapping .76
Table 74 – Transmit PDO Mapping.76
Table 75 – Sync Manager Communication Type .77
Table 76 – Sync Manager Channel 0 (Mailbox Receive).77
Table 77 – Sync Manager Channel 1 (Mailbox Send) .77
Table 78 – Sync Manager Channel 2 (Process Data Output) .78
Table 79 – Sync Manager Channel 3 (Process Data Input).78

Table 80 – Sync Manager Channel 4-32 .78
Table 81 – Sync Manager Synchronization .79
Table 82 – Initiate EoE Request .80
Table 83 – Initiate EoE Response.81
Table 84 – EoE Fragment Request.82
Table 85 – EoE Data .83
Table 86 – Set IP Parameter Request.84
Table 87 – Set IP Parameter Response.85
Table 88 – EoE Result Parameter .86
Table 89 – Set Address Filter Request .87
Table 90 – Set Address Filter Response.88
Table 91 – Read Request.89

– 6 – 61158-6-12 © IEC:2007(E)

Table 92 – Write Request.90

Table 93 – Data Request.91

Table 94 – Ack Request .92

Table 95 – Error Request .93

Table 96 – Error codes of FoE.93

Table 97 – Busy Request .94

Table 98 – State transitions and local management services .98

Table 99 – Primitives issued by ESM to DL.99

Table 100 – Primitives issued by DL to ESM.99
Table 101 – Primitives issued by Application to ESM . 100
Table 102 – Primitives issued by ESM to Application . 100
Table 103 – ESM state table .101
Table 104 – ESM Functions. 109
Table 105 – Primitives issued by Mailbox handler to DL. 110
Table 106 – Primitives issued by DL to Mailbox handler. 110
Table 107 – Primitives issued by Protocol handler to Mailbox handler . 110
Table 108 – Primitives issued by Mailbox handler to Protocol handler . 111
Table 109 – Primitives issued by Application to CoESM . 112
Table 110 – Primitives issued by CoESM to Application . 113
Table 111 – CoESM state table .113
Table 112 – Primitives issued by Application to EoESM . 124
Table 113 – Primitives issued by EoESM to Application . 125
Table 114 – EoESM state table .126
Table 115 – Primitives issued by Application to FoESM . 130
Table 116 – Primitives issued by FoESM to Application . 131
Table 117 – FoESM state table.131

61158-6-12 © IEC:2007(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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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
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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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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
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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  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 61158-6-12 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 61158-6 series cancel and replace
IEC 61158-6:2003. This edition of this part constitutes a technical addition. This part also
replaces IEC/PAS 62407, published in 2005
This edition of IEC 61158-6 includes the following significant changes from the previous
edition:
a) deletion of the former Type 6 fieldbus for lack of market relevance;

– 8 – 61158-6-12 © IEC:2007(E)

b) addition of new types of fieldbuses;

c) partition of part 6 of the third edition into multiple parts numbered -6-2, -6-3, …

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

FDIS Report on voting
65C/476/FDIS 65C/487/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.
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.

61158-6-12 © IEC:2007(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:2007(E)

INDUSTRIAL COMMUNICATION NETWORKS –

FIELDBUS SPECIFICATIONS –
Part 5-12: 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
1) define the wire-representation of the service primitives defined in IEC 61158-5-12, and
2) define the externally visible behavior associated with their transfer.
This standard specify 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
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.

61158-6-12 © IEC:2007(E) – 11 –

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 61158-4-12, Industrial communication networks – Fieldbus specifications – Part 4-12:
Data-link layer protocol specification – 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 – Part 1: Naming and addressing
ISO/IEC 7498-3, Information technology – Open Systems Interconnection – Basic Reference
Model – Part 3: The Basic Model

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
IEEE 802.1D, 2004, IEEE Standard for Information technology – Telecommunications and
information exchange between systems – IEEE standard for local and metropolitan area

– 12 – 61158-6-12 © IEC:2007(E)

networks – Common specifications – Media access control (MAC) Bridges; available at


IEEE 802.1Q, 1998, IEEE Standard for Information technology – Telecommunications and

information exchange between systems – IEEE standard for Local and metropolitan area

networks – Virtual bridged local area networks Bridges; available at

IETF RFC 768, User Datagram Protocol; available at

IETF RFC 791, Internet Protocol; available at

IETF RFC 792, Internet Control Message Protocol; available at
3 Terms, definitions, symbols, abbreviations and conventions
For the purposes of this document, the following terms, definitions, symbols, abbreviations and
conventions apply.
3.1 Reference model terms and definitions
This standard is based in part on the concepts developed in ISO/IEC 7498-1 and ISO/IEC
7498-3, and makes use of the following terms defined therein:
3.1.1 correspondent (N)-entities [7498-1]
correspondent AL-entities  (N=7)
[7498-1]
3.1.2 (N)-entity
AL-entity  (N=7)
[7498-1]
3.1.3 (N)-layer
AL-layer  (N=7)
3.1.4 layer-management [7498-1]
3.1.5 peer-entities [7498-1]
3.1.6 primitive name [7498-3]
3.1.7 AL-protocol [7498-1]
3.1.8 AL-protocol-data-unit [7498-1]
3.1.9 reset [7498-1]
3.1.10 routing [7498-1]
[7498-1]
3.1.11 segmenting
[7498-1]
3.1.12 (N)-service
AL-service  (N=7)
[7498-1]
3.1.13 AL-service-data-unit
3.1.14 AL-simplex-transmission [7498-1]
3.1.15 AL-subsystem [7498-1]
3.1.16 systems-management [7498-1]
3.1.17 AL-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:
61158-6-12 © IEC:2007(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:2007(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
...