IEC 61158-4-24:2014

IEC 61158-4-24 ®
Edition 1.0 2014-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Industrial communication networks – Fieldbus specifications –
Part 4-24: Data-link layer protocol specification – Type 24 elements

Réseaux de communication industriels – Spécifications des bus de terrain –
Partie 4-24: Spécification du protocole de la couche liaison de données –
Éléments de type 24
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IEC 61158-4-24 ®
Edition 1.0 2014-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Industrial communication networks – Fieldbus specifications –

Part 4-24: Data-link layer protocol specification – Type 24 elements

Réseaux de communication industriels – Spécifications des bus de terrain –

Partie 4-24: Spécification du protocole de la couche liaison de données –

Éléments de type 24
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX XE
ICS 25.040.40; 35.100.20; 35.110 ISBN 978-2-8322-1730-6

– 2 – IEC 61158-4-24:2014 © IEC 2014

CONTENTS
FOREWORD . 6

INTRODUCTION . 8

1 Scope . 10

1.1 General . 10

1.2 Specifications . 10

1.3 Procedures . 10

1.4 Applicability . 11

1.5 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 . 13
3.3 Common terms and definitions . 13
3.4 Symbols and abbreviations . 15
3.5 Additional type 24 symbols and abbreviations . 16
3.6 Common Conventions . 17
3.7 Additional Type 24 conventions . 18
4 Overview of DL-protocol . 19
4.1 Characteristic feature of DL-protocol . 19
4.2 DL layer component . 20
4.3 Timing sequence . 20
4.4 Service assumed from PhL . 28
4.5 Local parameters, variable, counters, timers . 29
5 DLPDU structure . 34
5.1 Overview . 34
5.2 Basic format DLPDU structure . 35
5.3 Short format DLPDU structure . 43
6 DLE element procedure . 47
6.1 Overview . 47
6.2 Cyclic transmission control sublayer . 47
6.3 Send Receive Control . 96
7 DL-management layer (DLM) . 103

7.1 Overview . 103
7.2 Primitive definitions . 103
7.3 DLM protocol machine . 104
7.4 Functions . 113
Bibliography . 115

Figure 1 – Data-link layer component . 20
Figure 2 – Timing chart of fixed-width time slot type cyclic communication . 21
Figure 3 – Timing chart of configurable time slot type cyclic communication . 23
Figure 4 – Schematic Diagram of Communication Interrupt Occurrence . 25
Figure 5 – Timing relationship between cyclic transmission and data processing . 27
Figure 6 – Timing chart example of acyclic communication . 28

Figure 7 – Basic format DLPDU structure. 35

Figure 8 – Short format DLPDU structure . 43

Figure 9 – The state diagram of C1 master for fixed-width time slot . 49

Figure 10 – The state diagram of C2 master for fixed-width time slot . 55

Figure 11 – The state diagram of slave for fixed-width time slot . 59

Figure 12 – The state diagram of C1 master for configurable time slot . 62

Figure 13 – The state diagram of C2 master for configurable time slot . 70

Figure 14 – The state diagram of slave for configurable time slot . 73

Figure 15 – The state diagram of message initiator for basic format . 77
Figure 16 – The state diagram of message responder for basic format . 81
Figure 17 – The state diagram of message initiator for short format . 85
Figure 18 – The state diagram of message responder for short format . 89
Figure 19 – The state diagram of acyclic transmission protocol machine . 94
Figure 20 – Internal architecture of one-port SRC . 98
Figure 21 – Internal architecture of multi-port SRC . 98
Figure 22 – Internal architecture of serializer . 98
Figure 23 – Internal architecture of deserializer . 100
Figure 24 – State diagram of C1 master DLM . 105
Figure 25 – State diagram of Slave and C2 master DLM . 110

Table 1 – State transition descriptions . 18
Table 2 – Description of state machine elements . 18
Table 3 – Conventions used in state machines . 18
Table 4 – Characteristic features of the fieldbus data-link protocol . 19
Table 5 – List of the values of variable Cyc_sel . 29
Table 6 – List of the values of variable Tunit . 30
Table 7 – List of the values of variable PDUType . 32
Table 8 – List of the values of variable SlotType . 32
Table 9 – Transfer syntax for bit sequences . 34
Table 10 – Bit order . 35
Table 11 – Destination and Source address format . 36

Table 12 – Station address . 36
Table 13 – Extended address . 36
Table 14 – Message control field format (Information transfer format) . 36
Table 15 – Message control field format (Supervisory format) . 37
Table 16 – The list of Supervisory function bits . 37
Table 17 – Frame type and Data length format . 37
Table 18 – The list of Frame type. 38
Table 19 – Data format of Synchronous frame . 38
Table 20 – The field list of Synchronous frame. 39
Table 21 – Data format of Output data or Input data frame. 39
Table 22 – The field list of Output data or Input data frame . 39
Table 23 – Data format of Delay measurement start frame . 40

– 4 – IEC 61158-4-24:2014 © IEC 2014

Table 24 – The field list of Delay measurement start frame . 40

Table 25 – Data format of Delay measurement frame. 40

Table 26 – The field list of Delay measurement frame . 40

Table 27 – Data format of Status frame. 41

Table 28 – The field list of Status frame . 41

Table 29 – The list of the DLE status . 41

Table 30 – The list of Repeater status . 42

Table 31 – Data format of Delay measurement frame. 42

Table 32 – The field list of Cycle Information frame. 42
Table 33 – Data format of Message frae . 43
Table 34 – The field list of Message frame . 43
Table 35 – Range of Station address field. 44
Table 36 – Control field format (I/O data exchange format) . 44
Table 37 – Control field format (Message format) . 44
Table 38 – The field list of Message format . 45
Table 39 – Data format of Synchronous frame . 45
Table 40 – The field list of Sync frame . 46
Table 41 – Data format of Output data frame . 46
Table 42 – The field list of Output data frame . 46
Table 43 – Data format of Input data frame . 46
Table 44 – The field list of Input data frame . 46
Table 45 – The primitives and parameters for DLS-user interface issued by DLS-user . 47
Table 46 – The primitives and parameters for DLS-user interface issued by CTC . 47
Table 47 – The state table of C1 master for fixed-width time slot . 49
Table 48 – The state table of C2 master for fixed-width time slot . 56
Table 49 – The state table of slave for fixed-width time slot . 59
Table 50 – The state table of C1 master for configurable time slot . 62
Table 51 – The state table of C2 master for configurable time slot . 71
Table 52 – The state table of slave for configurable time slot . 73
Table 53 – The list of functions used by cyclic transmission machine . 75
Table 54 – The state table of message initiator for basic format . 77

Table 55 – The state table of message responder for basic format . 81
Table 56 – The state table of message initiator for short format . 85
Table 57 – The state table of message responder for short format . 89
Table 58 – List of functions used by the message segmentation machine . 93
Table 59 – The state table of acyclic transmission protocol machine . 94
Table 60 – The list of functions used acyclic transmission protocol machine . 95
Table 61 – Primitives and parameters exchanged between CTC and DLM . 96
Table 62 – Error event primitive and parameters . 96
Table 63 – primitives and parameters for SRC-CTC interface . 97
Table 64 – Send frame primitive and parameters . 97
Table 65 – Receive frame primitives and parameters . 97
Table 66 – Primitives and parameters exchanged between SRC and DLM . 102

Table 67 – Get value primitive and parameters . 103

Table 68 – Error event primitive and parameters . 103

Table 69 – The list of primitives and parameters (DLMS-user source) . 103

Table 70 – The list of primitives and parameters (DLM source) . 104

Table 71 – State table of C1-Master DLM . 105

Table 72 – State table of Slave and C2 master DLM . 110

Table 73 – The list of the functions used by DLM protocol machine . 113

– 6 – IEC 61158-4-24:2014 © IEC 2014

INTERNATIONAL ELECTROTECHNICAL COMMISSION

____________
INDUSTRIAL COMMUNICATION NETWORKS –

FIELDBUS SPECIFICATIONS –
Part 4-24: Data-link layer protocol specification –

Type 24 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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with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
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4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC 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.
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 61158-4-24 has been prepared by subcommittee 65C: Industrial
networks, of IEC technical committee 65: Industrial-process measurement, control and
automation.
The text of this standard is based on the following documents:

FDIS Report on voting
65C/762/FDIS 65C/772/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 the 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.
– 8 – IEC 61158-4-24:2014 © IEC 2014

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.

The data-link protocol provides the data-link service by making use of the services available

from the physical 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 data-link

entities (DLEs) 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:

a) as a guide for implementors and designers;
b) for use in the testing and procurement of equipment;
c) as part of an agreement for the admittance of systems into the open systems environment;
d) 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.
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 profile series. Use of the various protocol types in other combinations
may require permission from their respective intellectual-property-right holders.
The International Electrotechnical Commission (IEC) draws attention to the fact that it is
claimed that compliance with this document may involve the use of patents as follows, where
the [xx] notation indicates the holder of the patent right:
US 8223804 [YE] COMMUNICATION DEVICE, SYNCHRONIZED
JP 4760978 SYSTEM, AND SYCHRONIZED COMMUNICATION METHOD
CN 200880002225.3
EPC 08738862.5
KR 10-2009-7011514
TW 97111183
US 7769935 [YE] MASTER SLAVE COMMUNICATION SYSTEM AND MASTER
JP 4683346 SLAVE COMMUNICATION METHOD
US 8046512
EPC 07850686.2
TW 96150287
JP 4356698 [YE] COMMUNICATION DEVICE, SYNCHRONIZED COMMUNICATION
SYSTEM, AND SYCHRONIZED COMMUNICATION METHOD
IEC takes no position concerning the evidence, validity and scope of this patent right.
The holders of these patent rights have assured IEC that they are willing to negotiate licenses
either free of charge or under reasonable and non-discriminatory terms and conditions with
applicants throughout the world. In this respect, the statement of the holders of these patent
rights is registered with IEC. Information may be obtained from
[YE] YASKAWA ELECTRIC CORPORATION
2-1 Kurosakishiroishi, Yahatanishi-ku, Kitakyushu 806-0004, Japan
Attention; Intellectual Property Rights Section.

Attention is drawn to the possibility that some of the elements of this document may be the

subject of patent rights other than those identified above. IEC shall not be held responsible for

identifying any or all such patent rights.

ISO (www.iso.org/patents) and IEC (http://patents.iec.ch) maintain on-line data bases of

patents relevant to their standards. Users are encouraged to consult the data bases for the

most up to date information concerning patents.

– 10 – IEC 61158-4-24:2014 © IEC 2014

INDUSTRIAL COMMUNICATION NETWORKS –

FIELDBUS SPECIFICATIONS –
Part 4-24: Data-link layer protocol specification –

Type 24 elements
1 Scope
1.1 General
The data-link layer provides basic time-critical messaging communications between devices in
an automation environment.
This protocol provides communication opportunities to all participating data-link entities
a) in a synchronously-starting cyclic manner, according to a pre-established schedule, or
b) in an acyclic manner, as requested by each of those data-link entities.
Thus this protocol can be characterized as one which provides cyclic and acyclic access
asynchronously but with a synchronous restart of each cycle.
1.2 Specifications
This standard specifies
a) procedures for the timely transfer of data and control information from one data-link user
entity to a peer user entity, and among the data-link entities forming the distributed
datalink service provider;
b) procedures for giving communications opportunities to all participating DL-entities,
sequentially and in a cyclic manner for deterministic and synchronized transfer at cyclic
intervals up to 64 ms;
c) procedures for giving communication opportunities available for time-critical data
transmission together with non-time-critical data transmission without prejudice to the
time-critical data transmission;
d) procedures for giving cyclic and acyclic communication opportunities for time-critical data
transmission with prioritized access;
e) procedures for giving communication opportunities based on standard ISO/IEC 8802-3

medium access control, with provisions for nodes to be added or removed during normal
operation;
f) the structure of the fieldbus DLPDUs used for the transfer of data and control information
by the protocol of this standard, and their representation as physical interface data units.
1.3 Procedures
The procedures are defined in terms of
a) the interactions between peer DL-entities (DLEs) through the exchange of fieldbus
DLPDUs;
b) the interactions between a DL-service (DLS) provider and a DLS-user in the same system
through the exchange of DLS primitives;
c) the interactions between a DLS-provider and a Ph-service provider in the same system
through the exchange of Ph-service primitives.

1.4 Applicability
These procedures are applicable to instances of communication between systems which

support time-critical communications services within the data-link layer of the OSI or fieldbus

reference models, and which require the ability to interconnect in an open systems

interconnection environment.
Profiles provide a simple multi-attribute means of summarizing an implementation’s

capabilities, and thus its applicability to various time-critical communications needs.

1.5 Conformance
This standard also specifies conformance requirements for systems implementing these
procedures. This standard does not contain tests to demonstrate compliance with such
requirements.
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.
IEC 61158-2, Industrial communication networks – Fieldbus specifications – Part 2: Physical
layer specification and service definition
IEC 61158-3-24:2014, Industrial communication networks – Fieldbus specifications –
Part 3-24: Data-link layer service definition – Type 24 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 8802-3:2000, 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 9899, Information technology – Programming languages – C
ISO/IEC 10731, Information technology – Open Systems Interconnection – Basic Reference
Model – Conventions for the definition of OSI services
ISO/IEC 13239:2002, Information technology – Telecommunications and information
exchange between systems – High-level data link control (HDLC) procedures
ISO/IEC 19501:2005, Information technology – Open Distributed Processing – Unified
Modeling Language (UML) Version 1.4.2

– 12 – IEC 61158-4-24:2014 © IEC 2014

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.

[ISO/IEC 7498-1]
acknowledgement
3.1.1
[ISO/IEC 7498-1]
correspondent (N)-entities
3.1.2
correspondent DL-entities (N=2)

correspondent Ph-entities (N=1)
[ISO/IEC 7498-3]
DL-address
3.1.3
[ISO/IEC 7498-1]
DL-protocol
3.1.4
[ISO/IEC 7498-1]
DL-protocol-data-unit
3.1.5
[ISO/IEC 7498-1]
DL-service-data-unit
3.1.6
[ISO/IEC 7498-1]
DLS-user
3.1.7
[ISO/IEC 7498-1]
DLS-user-data
3.1.8
[ISO/IEC 19501]
event
3.1.9
[ISO/IEC 7498-1]
layer-management
3.1.10
[ISO/IEC 7498-1]
primitive name
3.1.11
[ISO/IEC 7498-1]
reset
3.1.12
[ISO/IEC 7498-1]
segmenting
3.1.13
[ISO/IEC 19501]
state
3.1.14
[ISO/IEC 19501]
state machine
3.1.15
[ISO/IEC 7498-1]
systems-management
3.1.16
[ISO/IEC 19501]
transition
3.1.17
[ISO/IEC 7498-1]
(N)-entity
3.1.18
DL-entity (N=2)
Ph-entity (N=1)
[ISO/IEC 7498-1]
(N)-layer
3.1.19
DL-layer (N=2)
Ph-layer (N=1)
[ISO/IEC 7498-1]
(N)-service
DL-service (N=2)
Ph-service (N=1)
[ISO/IEC 7498-1]
(N)-service-access-point
DL-service-access-point (N=2)
Ph-service-access-point (N=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 confirm (primitive)
3.2.2 DL-service-primitive;
3.2.3 DL-service-provider
3.2.4 DL-service-user
3.2.5 indication (primitive)
3.2.6 request (primitive)
3.2.7 requestor
3.2.8 response (primitive)
3.3 Common terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.3.1
acyclic transmission
non-periodic exchange of telegrams
3.3.2
C1 master
one of the station type that initiates and control cyclic transmission
3.3.3
C1 message
message communication that C1 master operates as initiator to exchange messages with
slave or C2 master
3.3.4
C2 master
one of the station type that has the function of monitoring all process data transmitted through
the network and may initiates message communication
3.3.5
C2 message
message communication that C2 master operates as initiator to exchange messages with
slave or C1 master
3.3.6
cyclic transmission
periodic exchange of telegrams
3.3.7
data
generic term used to refer to any information carried over a fieldbus

– 14 – IEC 61158-4-24:2014 © IEC 2014

3.3.8
device
physical entity connected to the fieldbus composed of at least one communication element

(the network element) and which may have a control element and/or a final element

(transducer, actuator, etc.)
3.3.9
event driven mode
transmission mode for the application layer protocol of the communication type 24 in which a

transaction of command-response-exchanging arises as user’s demands

3.3.10
frame
synonym for DLPDU
3.3.11
initiator
station that initiates the exchange of process data or message
3.3.12
interface
shared boundary between two functional units, defined by functional characteristics, signal
characteristics, or other characteristics as appropriate
3.3.13
input data
process data sent by the slave and received by the C1 master
3.3.14
message
ordered series of octets intended to convey information
Note 1 to entry: Normally used to convey information between peers at the application layer.
3.3.15
monitor slave
slave that has the function of monitoring all process data transmitted through the network
3.3.16
network
set of nodes connected by some type of communication medium, including any intervening
repeaters, bridges, routers and lower-layer gateways

3.3.17
node
a) single DL-entity as it appears on one local link
b) end-point of a link in a network or a point at which two or more links meet
3.3.18
output data
process data sent by the C1 master and received by the slaves
3.3.19
protocol
convention about the data formats, time sequences, and error correction in the data exchange
of communication systems
3.3.20
real-time communication
transfer of data in real-time
3.3.21
receiving DLS-user
DL-service user that acts as a recipient of DL-user-data

Note 1 to entry: A DL-service user may be concurrently both a sending and receiving DLS-user.

3.3.22
responder
station that responds process data or message after it has been initiated by initiator
3.3.23
send data with acknowledge
data transfer service with acknowledge of reception from corresponding DLE
3.3.24
send data without acknowledge
data transfer service without acknowledge of reception from corresponding DLE
3.3.25
slave
one of the station type that accesses the medium only after it has been initiated by C1-maser
or C2 master
3.3.26
sending DLS-user
DL-service user that acts as a source of DL-user-data
3.3.27
station
node
3.3.28
topology
physical network architecture with respect to the connection between the stations of the
communication system"
3.3.29
transmission cycle
fixed time period of cyclic transmission
3.3.30
time slot
Time period reserved so that initiator and responder may exchange one frame respectively
3.4 Symbols and abbreviations
Destination address
DA
3.4.1
Data-link layer (as a prefix)
DL-
3.4.2
DL-entity (the local active instance of the data-link layer)
DLE
3.4.3
DL-layer
DLL
3.4.4
DL-management
DLM
3.4.5
– 16 – IEC 61158-4-24:2014 © IEC 2014

DL-management entity (the local active instance of DL-

DLME
management)
3.4.6
DL-management service
DLMS
3.4.7
DL-protocol-data-unit
DLPDU
3.4.8
DL-service
DLS
3.4.9
DL-service-access-point
DLSAP
3.4.10
DL-service-data-unit
DLSDU
3.4.11
First-in first-out (queuing method)
FIFO
3.4.12
Identifier
ID
3.4.13
Open systems interconnection
OSI
3.4.14
Protocol data unit
PDU
3.4.15
Physical layer (as a prefix)
Ph-
3.4.16
Ph-entity (the local active instance of the physical layer)
PhE
3.4.17
Ph-layer
PhL
3.4.18
Physical layer device (specified in ISO/IEC 8802-3)
PHY
3.4.19
Quality of service
QoS
3.4.20
Real-time
RT
3.4.21
Service access point
SAP
3.4.22
Service data unit
SDU
3.4.23
3.5 Additional type 24 symbols and abbreviations
Acknowledge
ACK
3.5.1
C1 message
C1MSG
3.5.2
C2 message
C2MSG
3.5.3
Input and/or output
I/O
3.5.4
Message
MSG
3.5.5
Receive
Rx
3.5.6
Send data with acknowledge
SDA
3.5.7
Send data without acknowledge
SDN
3.5.8
State machine
SM
3.5.9
Transmission cycle
Tcycle
3.5.10
Time slot
Tslot
...