IEC 61158-4-4:2023

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

IEC 61158-4-4:2023 specifies
- 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;
- the structure of the fieldbus DLPDUs used for the transfer of data and control information by the protocol of this document, and their representation as physical interface data units.

Réseaux de communication industriels - Spécifications des bus de terrain - Partie 4-4: Spécification du protocole de la couche liaison de données - Éléments de type 4

L'IEC 61158-4-4:2023 spécifie:
-les procédures de transfert en temps voulu des données et des informations de commande d’une entité utilisateur de liaison de données à une entité utilisateur homologue, et parmi les entités de liaison de données formant le fournisseur de services de liaison de données distribué;
-la structure des DLPDU de bus de terrain utilisées pour le transfert de données et d’informations de commande par le protocole du présent document, et leur représentation en tant qu’unités de données d’interface physique.

General Information

• Status: Published
• Publication Date: 21-Mar-2023
• 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: PPUB - Publication issued
• Start Date: 31-Mar-2023
• Completion Date: 22-Mar-2023

Relations

• Revises: IEC 61158-4-4:2019 - Industrial communication networks - Fieldbus specifications - Part 4-4: Data-link layer protocol specification - Type 4 elements
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC 61158-4-4 ®
Edition 4.0 2023-03
INTERNATIONAL
STANDARD
Industrial communication networks – Fieldbus specifications –
Part 4-4: Data-link layer protocol specification – Type 4 elements
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IEC 61158-4-4 ®
Edition 4.0 2023-03
INTERNATIONAL
STANDARD
Industrial communication networks – Fieldbus specifications –

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

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 25.040.40; 35.100.20; 35.110 ISBN 978-2-8322-6574-1

– 2 – IEC 61158-4-4:2023 © IEC 2023
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
1.1 General . 7
1.2 Specifications . 7
1.3 Procedures . 7
1.4 Applicability . 7
1.5 Conformance . 7
2 Normative references . 8
3 Terms, definitions, symbols and abbreviated terms . 8
3.1 Reference model terms and definitions . 8
3.2 Service convention terms and definitions . 10
3.3 Terms and definitions . 11
3.4 Symbols and abbreviations . 14
3.4.1 Constants, variables, counters and queues . 14
3.4.2 Miscellaneous . 14
4 Data Link Protocol Definition . 14
4.1 Overview of the DL-protocol . 14
4.1.1 General . 14
4.1.2 Functional classes . 15
4.1.3 Functions of the DLL . 15
4.1.4 Service assumed from the PhL . 24
4.2 General structure and encoding of PhIDUs and DLPDUs, and related
elements of procedure . 26
4.2.1 PhIDU structure and encoding . 26
4.2.2 Frame check sequence . 27
4.2.3 Common DLPDU structure, encoding and elements of procedure . 28
4.3 DLPDU-specific structure, encoding and elements of procedure . 33
4.3.1 DLPDU types . 33
4.3.2 Confirmed DLPDU . 33
4.3.3 Unconfirmed DLPDU. 34
4.3.4 Acknowledge DLPDU . 36
4.3.5 Immediate-reply DLPDU . 36
4.4 DL-service elements of procedure . 37
4.4.1 Receipt of a DL-UNITDATA request primitive . 37
4.4.2 Receipt of a DL-UNITDATA response primitive . 38
4.4.3 Autonomous DLE acknowledge . 39
4.4.4 Generation of a DL-UNITDATA indication primitive . 39
4.5 Route mechanism . 40
4.5.1 Type 4-route function . 40
4.5.2 Request Type 4-route generation . 41
4.5.3 DL-route generation . 42
4.6 Link-access system . 43
4.7 Local variables, counters and queues . 44
4.7.1 V(ACPDU) – acknowledge confirmed PDU . 44
4.7.2 V(AUPDU) – acknowledge unconfirmed PDU . 44
4.7.3 V(NA) – node-address . 44

4.7.4 V(NDLE) – number of DLEs . 44
4.7.5 V(PNR) – permitted number of retries . 44
4.7.6 V(DC) – device class (simple or normal) . 44
4.7.7 V(BR) – bit rate . 44
4.7.8 V(MID) – max indication delay . 45
4.7.9 V(DMRT) – default max retry time . 45
4.7.10 Q(UR) – user request queue . 45
4.7.11 C(LAC) – link access counter. 45
4.7.12 C(LIC) – link idle counter . 45
Bibliography . 46

Figure 1 – Relationship of PhE, DLE and DLS-user. 15
Figure 2 – DLE state diagram for confirmed and unconfirmed, unacknowledged
DLPDUs . 17
Figure 3 – DLE state diagram for confirmed acknowledged DLPDUs . 18
Figure 4 – DLE state diagram for unconfirmed acknowledged DLPDUs . 19
Figure 5 – Full duplex DLE receive state diagram . 20
Figure 6 – Full duplex DLE transmit state diagram . 20
Figure 7 – Link access example . 23
Figure 8 – Simple Type 4-route format . 28
Figure 9 – Extended Type 4-route format . 29
Figure 10 – Complex Type 4-route format . 29
Figure 11 – Immediate Type 4-route format . 30
Figure 12 – IP Type 4-route format . 30
Figure 13 – Control-status format . 31
Figure 14 – Data-field-format, one octet . 32
Figure 15 – Data field format, two octets . 32
Figure 16 – Source / destination designator . 41
Figure 17 – Simple Type 4-route generation . 41
Figure 18 – Extended Type 4-route generation . 42
Figure 19 – Complex and IP Type 4-route generation . 42
Figure 20 – Simple DL-route generation . 43
Figure 21 – Extended DL-route generation . 43
Figure 22 – Complex and IP DL-route generation . 43

Table 1 – Summary structure of DLPDUs . 33
Table 2 – Structure of confirmed DLPDUs . 34
Table 3 – Structure of unconfirmed DLPDUs . 35
Table 4 – Structure of acknowledge DLPDU. 36
Table 5 – Structure of immediate-reply DLPDU . 36

– 4 – IEC 61158-4-4:2023 © IEC 2023
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
INDUSTRIAL COMMUNICATION NETWORKS –
FIELDBUS SPECIFICATIONS –
Part 4-4: Data-link layer protocol specification –
Type 4 elements
FOREWORD
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