IEC 61158-6-26:2023

IEC 61158-6-26 ®
Edition 2.0 2023-03
INTERNATIONAL
STANDARD
Industrial communication networks – Fieldbus specifications –
Part 6-26: Application layer protocol specification – Type 26 elements

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IEC 61158-6-26 ®
Edition 2.0 2023-03
INTERNATIONAL
STANDARD
Industrial communication networks – Fieldbus specifications –

Part 6-26: Application layer protocol specification – Type 26 elements

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 25.040.40; 35.100.70; 35.110 ISBN 978-2-8322-6630-4

– 2 – IEC 61158-6-26:2023 © IEC 2023
CONTENTS
FOREWORD . 11
INTRODUCTION . 13
1 Scope . 14
1.1 General . 14
1.2 Specifications . 15
1.3 Conformance . 15
2 Normative references . 15
3 Terms, definitions, symbols, abbreviated terms and conventions . 16
3.1 Terms and definitions from other ISO/IEC standards . 17
3.1.1 Terms and definitions from ISO/IEC 7498-1 . 17
3.1.2 Terms and definitions from ISO/IEC 8822 . 17
3.1.3 Terms and definitions from ISO/IEC 9545 . 17
3.1.4 Terms and definitions from ISO/IEC 8824-1 . 17
3.1.5 Terms and definitions from ISO/IEC 8825-1 . 18
3.2 Type 26 specific terms and definitions . 18
3.3 Abbreviated terms and symbols . 22
3.4 Conventions . 24
3.4.1 Conventions used in state machines . 24
3.4.2 Convention for abstract syntax description . 26
3.4.3 Convention for reserved bits and octets . 26
3.4.4 Conventions for bit description in octets . 26
4 FAL syntax description . 27
4.1 General . 27
4.2 Overview of Type 26 fieldbus . 27
4.2.1 Application field and Common-memory . 27
4.2.2 Structure of Type 26 protocol . 28
4.2.3 Structure of Type 26 FAL . 29
4.2.4 Data link layer . 30
4.3 Operating principle . 31
4.3.1 Overview . 31
4.3.2 Logical ring maintenance . 31
4.3.3 Node addition . 34
4.3.4 Node in a logical ring . 38
4.3.5 Node drop-out . 39
4.3.6 Data transmission . 39
4.3.7 Data transmission frames . 49
4.4 FAL PDU abstract syntax . 52
4.4.1 Basic abstract syntax . 52
4.4.2 Transparent-msg- PDU . 55
4.4.3 Token-PDU . 55
4.4.4 Participation-req-PDU . 56
4.4.5 Byte-block-read PDUs . 56
4.4.6 Byte-block-write PDUs . 56
4.4.7 Word-block-read PDUs . 56
4.4.8 Word-block-write PDUs . 57
4.4.9 Network-parameter-read PDUs . 57
4.4.10 Network-parameter-write PDUs. 57

4.4.11 Stop-command PDUs . 57
4.4.12 Operation-command PDUs . 58
4.4.13 Profile-read PDUs . 58
4.4.14 Trigger-PDU . 58
4.4.15 Log-data-read PDUs . 58
4.4.16 Log-data-clear PDUs . 59
4.4.17 Message-return PDUs . 59
4.4.18 Vendor-specific-msg PDUs . 59
4.4.19 Start-TK-hld-time-mrmt PDUs . 60
4.4.20 Terminate-TK-hld-time-mrmt PDUs . 60
4.4.21 Start-GP_Comm-sndr-log PDUs . 60
4.4.22 Terminate-GP_Comm-sndr-log PDUs . 60
4.4.23 Set-remote-node-config-para PDUs . 61
4.4.24 Read-rmt-partici-node-mgt-info-para PDUs . 61
4.4.25 Read-rmt- node-mgt-info-para PDUs . 61
4.4.26 Read-rmt-node-set-info-para PDUs . 61
4.4.27 Reset-node PDUs . 62
4.4.28 Cyclic-data PDUs . 62
4.4.29 Extended-prticiption-req-PDU . 62
4.4.30 Extended-network-parameter-read PDUs . 63
4.4.31 Extended-network-parameter-write PDUs . 63
4.5 Data type assignments . 63
5 Transfer syntax . 65
5.1 Encoding rules . 65
5.1.1 Basic encoding . 65
5.1.2 Fixed length Unsigned encoding . 65
5.1.3 Fixed length BitString encoding . 65
5.1.4 OctetString encoding . 65
5.1.5 SEQUENCE encoding . 65
5.2 PDU elements encoding . 65
5.2.1 FALARHeader . 65
5.2.2 Transparent-msg PDU . 69
5.2.3 Token-PDU . 70
5.2.4 Participation-req-PDU . 71
5.2.5 Byte-block-read PDUs . 72
5.2.6 Byte-block-write PDUs . 74
5.2.7 Word-block-read PDUs . 75
5.2.8 Word-block-write PDUs . 77
5.2.9 Network-parameter-read PDUs . 79
5.2.10 Network-parameter-write PDUs. 83
5.2.11 Stop-command PDUs . 85
5.2.12 Operation-command PDUs . 87
5.2.13 Profile-read PDUs . 89
5.2.14 Trigger-PDU . 92
5.2.15 Log-data-read PDUs . 92
5.2.16 Log-data-clear PDUs . 98
5.2.17 Message-return PDUs . 100
5.2.18 Vendor-specific-msg PDUs . 102
5.2.19 Start-TK-hld-time-mrmt PDUs . 105

– 4 – IEC 61158-6-26:2023 © IEC 2023
5.2.20 Terminate-TK-hld-time-mrmt PDUs . 106
5.2.21 Start-GP_Comm-sndr-log PDUs . 110
5.2.22 Terminate-GP_Comm-sndr-log PDUs .
...