IEC 61158-4-21:2010

Industrial communication networks - Fieldbus specifications - Part 4-21: Data-link layer protocol specification - Type 21 elements

IEC 61158-4-21:2010 describes 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 data link service provider and procedures for giving communication opportunities based on standard ISO/IEC 8802-3 MAC, with provisions for nodes to be added or removed during normal operation; structure of the fieldbus data link protocol data units (DLPDUs) used for the transfer of data and control information by the protocol of this standard, and their representation as physical interface data units. This standard cancels and replaces IEC/PAS 62573 published in 2008. This bilingual version published in 2012-01 corresponds to the English version published in 2010-08.

Réseaux de communication industriels - Spécifications des bus de terrain - Partie 4-21: Spécification du protocole de la couche de liaison de données - Eléments de Type 21

La CEI 61158-4-21:2010 décrit des procédures de transfert en temps opportun de données et d'informations de commande d'une entité utilisateur de liaison de données à une entité utilisateur homologue ainsi qu'entre entités de liaison de données qui constituent le fournisseur de services distribués de la liaison; des procédures offrant des moyens de communication fondées sur le MAC de l'ISO/CEI 8802-3, ainsi que des dispositions permettant d'ajouter et de retirer des noeuds au cours du fonctionnement normal; la structure des unités de données de protocole de liaison de données (DLPDU) de bus de terrain utilisées pour le transfert des données et les informations de commande par le protocole objet de la présente norme, ainsi que leur représentation en tant qu'unité de données d'interface de couche physique. La présente norme annule et remplace la CEI/PAS 62573 publiée en 2008. La présente version bilingue publiée en 2012-01 correspond à la version anglaise monolingue publiée en 2010-08.

General Information

• Status: Published
• Publication Date: 04-Aug-2010
• ICS: 25.040.40 - Industrial process measurement and control
• ICS: 35.100.20 - Data link 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
• Completion Date: 10-Apr-2019

Relations

• Replaces: IEC PAS 62573:2008 - Real-time Ethernet - Real-time Automation Protocol for Industrial Ethernet (RAPIEnet)
• Effective Date: 05-Sep-2023
• Revised: IEC 61158-4-21:2019 - Industrial communication networks - Fieldbus specifications - Part 4-21: Data-link layer protocol specification - Type 21 elements
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC 61158-4-21 ®
Edition 1.0 2010-08
INTERNATIONAL
STANDARD
Industrial communication networks – Fieldbus specifications –
Part 4-21: Data-link layer protocol specification – Type 21 elements

All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form

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IEC 61158-4-21 ®
Edition 1.0 2010-08
INTERNATIONAL
STANDARD
Industrial communication networks – Fieldbus specifications –
Part 4-21: Data-link layer protocol specification – Type 21 elements

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
XD
ICS 25.04.40; 35.100.20; 35.110 ISBN 978-2-88912-091-8
– 2 – 61158-4-21 © IEC:2010(E)

CONTENTS
FOREWORD.6

INTRODUCTION.8

1 Scope.10

1.1 General .10

1.2 Specifications.10

1.3 Procedures.10

1.4 Applicability.10

1.5 Conformance.11
2 Normative references .11
3 Terms, definitions, symbols and abbreviations.11
3.1 Reference model terms and definitions.11
3.2 Service convention terms and definitions.13
3.3 Common terms and definitions .14
3.4 Symbols and abbreviations.17
4 Overview of the data-link protocol.18
4.1 General .18
4.2 Overview of medium access control .18
4.3 Service assumed from the physical layer.19
4.4 DLL architecture.19
4.5 Data type .21
4.6 Local parameters and variables.23
5 General structure and encoding.38
5.1 Overview .38
5.2 MAPDU structure and encoding.38
5.3 Common MAC frame structure, encoding and elements of procedure .39
5.4 Order of bit transmission .47
5.5 Invalid DLPDU.47
6 DLPDU structure and procedure .48
6.1 General .48
6.2 Common DLPDU Field .48
6.3 DL-DATA Transfer.48
6.4 DL-SPDATA Transfer .51

6.5 Network control messages .53
7 DLE elements of procedure .59
7.1 Overall structure.59
7.2 DL-protocol machine (DLPM) .59
7.3 DLL management Protocol .69
8 Constants and error codes .102
8.1 General .102
8.2 Constants.102
8.3 Data-link layer error codes .104
Bibliography.105

Figure 1 – Relationships of DLSAPs, DLSAP-addresses, and group DL-addresses .15
Figure 2 – Interaction of PhS primitives with DLE.19

61158-4-21 © IEC:2010(E) – 3 –

Figure 3 – Data-link layer architecture .20

Figure 4 – Common MAC frame format for Type 21 DLPDU .39

Figure 5 – MAC frame format for other protocols.39

Figure 6 – Version and Length field .40

Figure 7 – DST_addr field.41

Figure 8 – SRC_addr field.42

Figure 9 – Frame Control Field .43

Figure 10 – Extension field .45

Figure 11 – DSAP field .46
Figure 12 – Source service access point field .46
Figure 13 – Length of group mask and extension information.47
Figure 14 – Group mask option field .47
Figure 15 – Common DLPDU field .48
Figure 16 – Building a DT DLPDU.49
Figure 17 – DT DLPDU structure .49
Figure 18 – SPDT DLPDU structure .52
Figure 19 – NCM_LA DLPDU structure .54
Figure 20 – DLL structure and elements .59
Figure 21 – State transition diagram of the DLPM .63
Figure 22 – State transition diagram of DLM .73

Table 1 – DLL components .20
Table 2 – UNSIGNEDn data type .22
Table 3 – INTEGERn data type.23
Table 4 – DLE configuration parameters .24
Table 5 – Queues to support data transfer .25
Table 6 – Variables to support SAP management .26
Table 7 – Variables to support device information management.26
Table 8 – DL–entity identifier .27
Table 9 – Device Flags .27
Table 10 – DLM state.27

Table 11 – Device Unique Identification .28
Table 12 – Unique identification of device connected to R-port1 .28
Table 13 – Unique identification of device connected to R-port2 .28
Table 14 – MAC address.28
Table 15 – Port information.29
Table 16 – Protocol version .29
Table 17 – Device type .30
Table 18 – Device description.30
Table 19 – Hop count.30
Table 20 – Variables to support managing network information.31
Table 21 – Topology .31
Table 22 – Collision count.31

– 4 – 61158-4-21 © IEC:2010(E)

Table 23 – Device count .32

Table 24 – Topology change count .32

Table 25 – Last topology change time.32

Table 26 – RNMP device UID .32

Table 27 – RNMS device UID .33

Table 28 – LNM device UID for R-port1 .33

Table 29 – LNM device UID for R-port2 .33

Table 30 – Network flags .34

Table 31 – Variables and counter to support managing path information.
...

IEC 61158-4-21 ®
Edition 1.0 2010-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Industrial communication networks – Fieldbus specifications –
Part 4-21: Data-link layer protocol specification – Type 21 elements

Réseaux de communication industriels – Spécifications des bus de terrain –
Partie 4-21: Spécification du protocole de la couche de liaison de données –
Eléments de Type 21
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form

or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from

either IEC or IEC's member National Committee in the country of the requester.
If you have any questions about IEC copyright or have an enquiry about obtaining additional rights to this publication,

please contact the address below or your local IEC member National Committee for further information.

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International Standards for all electrical, electronic and related technologies.

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latest edition, a corrigenda or an amendment might have been published.

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IEC 61158-4-21 ®
Edition 1.0 2010-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Industrial communication networks – Fieldbus specifications –

Part 4-21: Data-link layer protocol specification – Type 21 elements

Réseaux de communication industriels – Spécifications des bus de terrain –

Partie 4-21: Spécification du protocole de la couche de liaison de données –

Eléments de Type 21
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
XD
CODE PRIX
ICS 25.040.40; 35.100.20; 35.110 ISBN 978-2-88912-860-0

– 2 – 61158-4-21  IEC:2010
CONTENTS
FOREWORD . 6

INTRODUCTION . 8

1 Scope . 10

1.1 General . 10

1.2 Specifications . 10

1.3 Procedures . 10

1.4 Applicability . 10

1.5 Conformance . 11
2 Normative references . 11
3 Terms, definitions, symbols and abbreviations . 11
3.1 Reference model terms and definitions . 11
3.2 Service convention terms and definitions . 13
3.3 Common terms and definitions . 14
3.4 Symbols and abbreviations . 17
4 Overview of the data-link protocol. 18
4.1 General . 18
4.2 Overview of medium access control . 18
4.3 Service assumed from the physical layer . 19
4.4 DLL architecture . 19
4.5 Data type . 21
4.6 Local parameters and variables . 23
5 General structure and encoding . 38
5.1 Overview . 38
5.2 MAPDU structure and encoding . 38
5.3 Common MAC frame structure, encoding and elements of procedure . 39
5.4 Order of bit transmission . 47
5.5 Invalid DLPDU . 47
6 DLPDU structure and procedure . 48
6.1 General . 48
6.2 Common DLPDU Field . 48
6.3 DL-DATA Transfer . 48
6.4 DL-SPDATA Transfer . 51

6.5 Network control messages . 53
7 DLE elements of procedure . 59
7.1 Overall structure . 59
7.2 DL-protocol machine (DLPM) . 59
7.3 DLL management Protocol . 69
8 Constants and error codes . 102
8.1 General . 102
8.2 Constants . 102
8.3 Data-link layer error codes . 104
Bibliography . 105

Figure 1 – Relationships of DLSAPs, DLSAP-addresses, and group DL-addresses . 15
Figure 2 – Interaction of PhS primitives with DLE . 19

61158-4-21  IEC:2010 – 3 –
Figure 3 – Data-link layer architecture . 20

Figure 4 – Common MAC frame format for Type 21 DLPDU . 39

Figure 5 – MAC frame format for other protocols . 39

Figure 6 – Version and Length field . 40

Figure 7 – DST_addr field . 41

Figure 8 – SRC_addr field. 42

Figure 9 – Frame Control Field . 43

Figure 10 – Extension field . 45

Figure 11 – DSAP field . 46
Figure 12 – Source service access point field . 46
Figure 13 – Length of group mask and extension information . 47
Figure 14 – Group mask option field . 47
Figure 15 – Common DLPDU field . 48
Figure 16 – Building a DT DLPDU . 49
Figure 17 – DT DLPDU structure . 49
Figure 18 – SPDT DLPDU structure . 52
Figure 19 – NCM_LA DLPDU structure . 54
Figure 20 – DLL structure and elements . 59
Figure 21 – State transition diagram of the DLPM . 63
Figure 22 – State transition diagram of DLM . 73

Table 1 – DLL components . 20
Table 2 – UNSIGNEDn data type . 22
Table 3 – INTEGERn data type . 23
Table 4 – DLE configuration parameters . 24
Table 5 – Queues to support data transfer . 25
Table 6 – Variables to support SAP management . 26
Table 7 – Variables to support device information management . 26
Table 8 – DL–entity identifier .
...