IEC 61158-4-2:2023

Industrial communication networks - Fieldbus specifications - Part 4-2: Data-link layer protocol specification - Type 2 elements

IEC 61158-4-2:2023 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 document 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:
- as a guide for implementers 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.

Réseaux de communication industriels - Spécifications des bus de terrain - Partie 4-2: Spécification du protocole de la couche liaison de données - Éléments de type 2

L'IEC 61158-4-2:2023 appartient à la série de normes visant à faciliter l’interconnexion des composants du système d’automatisation. Elle est liée aux autres normes de la série telle que définie par le modèle de référence de bus de terrain "à trois couches" décrit dans l’IEC 61158‑1.
Le protocole de liaison de données assure un service de liaison de données en s’appuyant sur les services offerts par la couche physique. Le présent document a pour principal objet de préciser un ensemble de règles de communication, exprimées sous la forme de procédures que doivent réaliser des entités de liaison de données homologues (DLE) au moment de la communication. Ces règles de communication ont pour vocation de fournir une base de développement stable visant à atteindre différents objectifs:
guider les implémenteurs et les concepteurs;
réaliser les essais et acquérir l’équipement;
dans un accord d’intégration des systèmes dans l’environnement de systèmes ouverts;
dans le cadre d’une meilleure compréhension des communications prioritaires au sein de l’OSI.

General Information

• Status: Published
• Publication Date: 08-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: 09-Mar-2023

Relations

• Revises: IEC 61158-4-2:2019 - Industrial communication networks - Fieldbus specifications - Part 4-2: Data-link layer protocol specification - Type 2 elements
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC 61158-4-2 ®
Edition 5.0 2023-03
INTERNATIONAL
STANDARD
colour
inside
Industrial communication networks – Fieldbus specifications –
Part 4-2: Data-link layer protocol specification – Type 2 elements
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IEC 61158-4-2 ®
Edition 5.0 2023-03
INTERNATIONAL
STANDARD
colour
inside
Industrial communication networks – Fieldbus specifications –

Part 4-2: Data-link layer protocol specification – Type 2 elements

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 25.040.40; 35.100.20; 35.110 ISBN 978-2-8322-6554-3

– 2 – IEC 61158-4-2:2023 © IEC 2023
CONTENTS
FOREWORD . 16
INTRODUCTION . 18
1 Scope . 19
1.1 General . 19
1.2 Specifications . 19
1.3 Procedures . 19
1.4 Applicability . 20
1.5 Conformance . 20
2 Normative references . 20
3 Terms, definitions, symbols, abbreviated terms and conventions . 22
3.1 Reference model terms and definitions . 22
3.2 Service convention terms and definitions . 24
3.3 Common terms and definitions . 24
3.4 Additional Type 2 definitions . 25
3.5 Type 2 symbols and abbreviated terms . 33
3.6 Conventions for station management objects . 34
4 Overview of the data-link protocol . 35
4.1 General . 35
4.1.1 DLL architecture . 35
4.1.2 Access control machine (ACM) and scheduling support functions . 37
4.1.3 Connection-mode, connectionless-mode data transfer and DL service . 37
4.2 Services provided by the DL . 37
4.2.1 Overview . 37
4.2.2 QoS . 38
4.3 Structure and definition of DL-addresses . 38
4.3.1 General . 38
4.3.2 MAC ID address . 39
4.3.3 Generic tag address . 40
4.3.4 Fixed tag address . 40
4.4 Services assumed from the PhL . 41
4.4.1 General requirements . 41
4.4.2 Data encoding rules . 41
4.4.3 DLL to PhL interface . 42
4.5 Functional classes . 44
5 General structure and encoding of PhIDUs and DLPDUs and related elements of
procedure . 44
5.1 Overview. 44
5.2 Media access procedure . 44
5.3 DLPDU structure and encoding . 48
5.3.1 General . 48
5.3.2 DLPDU components . 48
5.3.3 Preamble . 48
5.3.4 Start and end delimiters . 48
5.3.5 DLPDU octets and ordering . 48
5.3.6 Source MAC ID . 49
5.3.7 Lpackets field . 49
5.3.8 Frame check sequence (FCS) . 49

5.3.9 Null DLPDU . 52
5.3.10 Abort DLPDU . 52
5.4 Lpacket components . 52
5.4.1 General Lpacket structure. 52
5.4.2 Size . 53
5.4.3 Control . 53
5.4.4 Generic tag Lpackets . 53
5.4.5 Fixed tag Lpackets . 54
5.5 DLPDU procedures . 54
5.5.1 General . 54
5.5.2 Sending scheduled DLPDUs . 55
5.5.3 Sending unscheduled DLPDUs . 55
5.5.4 Receiving DLPDUs . 55
5.6 Summary of DLL support services and objects . 56
6 Specific DLPDU structure, encoding and procedures . 57
6.1 Modeling language . 57
6.1.1 State machine description. 57
6.1.2 Use of DLL- prefix . 58
6.1.3 Data types . 58
6.2 DLS user services . 59
6.2.1 General . 59
6.2.2 Connected mode and connectionless mode transfer service . 60
6.2.3 Queue maintenance service . 61
6.2.4 Tag filter service . 61
6.2.5 Link synchronization service . 62
6.2.6 Synchronized parameter change service. 62
6.2.7 Event reports service . 63
6.2.8 Bad FCS service . 64
6.2.9 Current moderator service . 64
6.2.10 Power up and online services . 64
6.2.11 Enable moderator service . 65
6.2.12 Listen only service . 65
6.3 Generic tag Lpacket . 65
6.3.1 General . 65
6.3.2 Structure of the generic-tag Lpacket . 65
6.3.3 Sending and receiving the generic-tag Lpacket . 66
6.4 Moderator Lpacket . 66
6.4.1 General . 66
6.4.2 Structure of the moderator Lpacket . 66
6.4.3 Sending and receiving the moderator Lpacket . 66
6.5 Time distribution Lpacket . 67
6.5.1 General . 67
6.5.2 Structure of the time distribution Lpacket . 67
6.5.3 Sending and receiving the time distribution Lpacket . 69
6.6 UCMM Lpacket . 70
6.6.1 General . 70
6.6.2 Structure of the UCMM Lpacket . 70
6.6.3 Sending and receiving the UCMM Lpacket . 70
6.7 Keeper UCMM Lpacket . 70

– 4 – IEC 61158-4-2:2023 © IEC 2023
6.7.1 General .
...