IEC 61158-6-2:2023

Industrial communication networks - Fieldbus specifications - Part 6-2: Application layer protocol specification - Type 2 elements

IEC 61158-6-2:2023 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 2 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.

Réseaux de communication industriels - Spécifications des bus de terrain - Partie 6-2: Spécification du protocole de la couche application - Éléments de type 2

L'IEC 61158-6-2:2023 fournit des éléments communs pour les communications prioritaires ou non entre des programmes d’application dans un environnement et avec un matériel d’automatisation spécifiques aux bus de terrain de type 2. Le terme "à temps critique" est utilisé pour indiquer la présence d’une fenêtre temporelle, dans laquelle il est exigé de réaliser une ou plusieurs actions spécifiées selon un niveau défini de certitude. Tout manquement à réaliser ces actions dans la fenêtre de temps prévue risque de provoquer la défaillance des applications qui les demandent, avec le risque de mettre en danger l’équipement, l’usine, voire les personnes.

General Information

• Status: Published
• Publication Date: 23-Mar-2023
• ICS: 25.040.40 - Industrial process measurement and control
• ICS: 35.100.70 - Application 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: 24-Mar-2023

Relations

• Revises: IEC 61158-6-2:2019 - Industrial communication networks - Fieldbus specifications - Part 6-2: Application layer protocol specification - Type 2 elements
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC 61158-6-2 ®
Edition 5.0 2023-03
INTERNATIONAL
STANDARD
Industrial communication networks – Fieldbus specifications –
Part 6-2: Application layer protocol specification – Type 2 elements

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IEC 61158-6-2 ®
Edition 5.0 2023-03
INTERNATIONAL
STANDARD
Industrial communication networks – Fieldbus specifications –

Part 6-2: Application layer protocol specification – Type 2 elements

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 25.040.40; 35.100.70; 35.110 ISBN 978-2-8322-6631-1

– 2 – IEC 61158-6-2:2023 © IEC 2023
CONTENTS
FOREWORD . 14
INTRODUCTION . 17
1 Scope . 18
1.1 General . 18
1.2 Specifications . 18
1.3 Conformance . 19
2 Normative references . 19
3 Terms, definitions, symbols, abbreviated terms and conventions . 21
3.1 Terms and definitions from other ISO/IEC standards . 21
3.1.1 Terms and definitions from ISO/IEC 7498-1 . 21
3.1.2 Terms and definitions from ISO/IEC 9545 . 21
3.1.3 Terms and definitions from ISO/IEC 8824-1 . 22
3.1.4 Terms and definitions from ISO/IEC 8825-1 . 22
3.2 Terms and definitions from IEC 61158-5-2 . 22
3.3 Additional terms and definitions . 22
3.4 Abbreviated terms and symbols . 30
3.5 Conventions . 30
3.5.1 General concept . 30
3.5.2 Attribute specification . 31
3.5.3 Common services . 31
3.5.4 State machine conventions . 34
4 Abstract syntax . 36
4.1 FAL PDU abstract syntax . 36
4.1.1 General . 36
4.1.2 PDU structure . 36
4.1.3 UCMM_PDUs . 39
4.1.4 Transport_Headers . 40
4.1.5 CM_PDUs . 43
4.1.6 CM PDU components . 56
4.1.7 MR headers . 65
4.1.8 OM_Service_PDU . 66
4.1.9 Message and connection paths . 130
4.1.10 Class, attribute and service codes . 146
4.1.11 Error codes . 154
4.2 Data abstract syntax specification . 169
4.2.1 Transport format specification . 169
4.2.2 Abstract syntax notation . 170
4.2.3 Control network data specification . 170
4.2.4 Data type specification / dictionaries . 172
4.3 Encapsulation abstract syntax . 174
4.3.1 Encapsulation protocol . 174
4.3.2 Encapsulation messages . 175
4.3.3 Command descriptions . 178
4.3.4 Common packet format . 190
5 Transfer syntax . 194
5.1 Compact encoding . 194

5.1.1 Encoding rules . 194
5.1.2 Encoding constraints . 195
5.1.3 Examples. 195
5.2 Data type reporting . 202
5.2.1 Object data representation. 202
5.2.2 Elementary data type reporting . 202
5.2.3 Constructed data type reporting . 203
6 Structure of FAL protocol state machines . 209
7 AP-Context state machine . 210
7.1 Overview. 210
7.2 Connection object state machine . 210
7.2.1 I/O Connection instance behavior . 210
7.2.2 Bridged Connection instance behavior . 215
7.2.3 Explicit Messaging Connection instance behavior . 217
8 FAL service protocol machine (FSPM) . 219
8.1 General . 219
8.2 Primitive definitions . 219
8.3 Parameters of primitives . 224
8.4 FSPM state machines . 225
9 Application relationship protocol machines (ARPMs) . 225
9.1 General . 225
9.2 Connection-less ARPM (UCMM) . 226
9.2.1 General . 226
9.2.2 Primitive definitions . 226
9.2.3 Parameters of primitives . 227
9.2.4 UCMM state machines . 228
9.2.5 Examples of UCMM sequences . 233
9.2.6 Management UCMM . 235
9.3 Connection-oriented ARPMs (transports) . 236
9.3.1 Transport PDU buffer . 236
9.3.2 Transport classes . 237
9.3.3 Common primitive definitions . 237
9.3.4 Parameters of common primitives . 238
9.3.5 Transport state machines – class 0 . 238
9.3.6 Transport state machines – class 1 . 242
9.3.7 Transport state machines – class 2 . 247
9.3.8 Transport state machines – class 3 . 255
10 DLL mapping protocol machine 1 (DMPM 1) . 265
10.1 General . 265
10.2 Link producer . 265
10.3 Link consumer . 266
10.4 Primitive definitions . 266
10.4.1 Primitives exchanged between DMPM and ARPM . 266
10.4.2 Parameters of ARPM/DMPM primitives . 266
10.4.3 Primitives exchanged between data-link layer and DMPM . 266
10.4.4 Parameters of DMPM/Data-link Layer primitives . 267
10.4.5 Network connection ID . 268
10.5 DMPM state machine . 268

– 4 – IEC 61158-6-2:2023 © IEC 2023
10.5.1 DMPM states . 268
10.5.2 Functions used by DMPM . 270
10.6 Data-link Layer service selection. 270
11 DLL mapping protocol machine 2 (DMPM 2) .
...