IEC 61158-4-1:2014

IEC 61158-4-1 ®
Edition 2.0 2014-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Industrial communication networks – Fieldbus specifications –
Part 4-1: Data-link layer protocol specification – Type 1 elements

Réseaux de communication industriels – Spécifications des bus de terrain –
Partie 4-1: Spécification du protocole de la couche liaison de données –
Éléments de type 1
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IEC 61158-4-1 ®
Edition 2.0 2014-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Industrial communication networks – Fieldbus specifications –

Part 4-1: Data-link layer protocol specification – Type 1 elements

Réseaux de communication industriels – Spécifications des bus de terrain –

Partie 4-1: Spécification du protocole de la couche liaison de données –

Éléments de type 1
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
XH
CODE PRIX
ICS 25.040.40; 35.100.20; 35.110 ISBN 978-2-8322-1719-1

– 2 – IEC 61158-4-1:2014 © IEC 2014
CONTENTS
FOREWORD . 9
0 INTRODUCTION . 11
0.1 General . 11
0.2 Nomenclature for references within this standard . 11
1 Scope . 12
1.1 General . 12
1.2 Specifications . 12
1.3 Procedures . 12
1.4 Applicability . 13
1.5 Conformance . 13
2 Normative references . 13
3 Terms, definitions, symbols and abbreviations . 14
3.1 Reference model terms and definitions . 14
3.2 Service convention terms and definitions . 16
3.3 Terms and definitions . 16
3.4 Symbols and abbreviations . 25
4 Overview of the DL-protocol . 29
4.1 Three-level model of the DLL . 29
4.2 Service provided by the DLL . 31
4.3 Structure and definition of DL-addresses . 38
4.4 Service assumed from the PhL . 50
4.5 Functions of the DLL . 52
4.6 Functional classes . 55
4.7 Local parameters, variables, counters, timers and queues . 56
5 General structure and encoding of PhIDUs and DLPDUs, and related elements of
procedure . 70
5.1 PhIDU structure and encoding . 70
5.2 Common DLPDU structure, encoding and elements of procedure . 70
6 DLPDU-specific structure, encoding and elements of procedure . 81
6.1 Establish connection (EC) DLPDU . 83
6.2 Disconnect connection (DC) DLPDU . 85
6.3 Reset connection (RC) DLPDU . 88
6.4 Compel acknowledgement (CA) DLPDU . 89
6.5 Compel data (CD) DLPDU . 96
6.6 Exchange data (ED) DLPDU . 103
6.7 Data (DT) DLPDU . 111
6.8 Status response (SR) DLPDU . 118
6.9 Compel time (CT) DLPDU . 121
6.10 Time distribution (TD) DLPDU . 123
6.11 Round-trip-delay query (RQ) DLPDU . 125
6.12 Round-trip-delay reply (RR) DLPDU . 127
6.13 Probe node DL-address (PN) DLPDU . 129
6.14 Probe response (PR) DLPDU . 131
6.15 Pass token (PT) DLPDU . 133
6.16 Execute sequence (ES) DLPDU . 141
6.17 Return token (RT) DLPDU . 148

6.18 Request interval (RI) DLPDU . 149
6.19 Claim LAS (CL) DLPDU . 150
6.20 Transfer LAS (TL) DLPDU . 152
6.21 Wakeup (WK) DLPDU . 155
6.22 Idle (IDLE) DLPDU . 157
6.23 Spare DLPDUs . 158
6.24 Reserved (not to be used) DLPDUs . 159
7 DLPDU-parameter structure and encoding . 160
7.1 Structure and encoding of EC-PARAMETERS . 160
7.2 Structure and encoding of DC-PARAMETERS . 165
7.3 Structure and encoding of RC-PARAMETERS . 166
7.4 Structure and encoding of SD-Parameters . 168
7.5 Structure and encoding of SR-parameters . 176
7.6 Structure and encoding of TD-parameters . 176
7.7 Structure and encoding of RQ-parameters . 179
7.8 Structure and encoding of RR-parameters . 179
7.9 Structure and encoding of PN-parameters . 180
7.10 Structure and encoding of DD-parameters . 182
8 DL-service elements of procedure . 182
8.1 Operation of the DL(SAP)-address, buffer and queue management services . 183
8.2 Operation of the connection-mode services . 186
8.3 Operation of the connectionless-mode services . 226
8.4 Operation of the scheduling guidance services . 237
9 DL-support subprotocol . 246
9.1 General . 246
9.2 Overview of LAS operation . 247
9.3 DL-support subprotocol definition . 247
9.4 Elements of Procedures for receiving SPDUs . 280
10 Other DLE elements of procedure. 282
10.1 DLE initialization . 282
10.2 LAS behavior and operation . 286
10.3 DL-support operation . 293
10.4 DL-bridge elements of procedure and bridge sub-protocol . 298
10.5 DL-management-information . 328
10.6 Implementation profiles . 332
11 PICS proforma . 337
11.1 Introduction . 338
11.2 General . 338
11.3 Normative references . 338
11.4 Definitions . 338
11.5 Abbreviations . 338
11.6 Conformance . 339
11.7 Instructions . 339
11.8 Identification. 339
11.9 Implementation profile . 340
11.10 Major low-level capabilities . 344
11.11 Major high-level capabilities . 357
Annex A (informative) Exemplary FCS implementation . 366

– 4 – IEC 61158-4-1:2014 © IEC 2014
Annex B (informative) Type 1: Formal protocol finite state machines. 368
B.1 Basic reception and transmission FSMs . 368
B.2 FSMs for DLCs . 379
B.3 FSMs for scheduling . 385
B.4 FSMs for bridges . 385
Annex C (informative) Type 1: DLPDU and DL-addressing short-form summaries . 387
C.1 Fields used in short-form summaries . 387
C.2 DLPDU short-form summary grouped by function . 388
C.3 DLPDU short-form summary in alphabetic order of DLPDU names . 390
C.4 DLPDU short-form summary in alphabetic order of DLPDU acronyms . 391
C.5 DLPDU FC code-point assignment matrix – overview and detail . 392
C.6 SD-parameters (status and data-description parameters) of CA, CD, ED and
DT DLPDUs . 395
C.7 EC parameters of EC DLPDUs . 398
C.8 Parameters of DC and RC DLPDUs . 400
C.9 Parameters of TD, RQ and RR DLPDUs . 401
C.10 Parameters of PN, PT, ES and RI DLPDUs . 404
C.11 Addressing summary extracted from figures and tables of 4.3 . 404
Bibliography . 409

Figure 1 – Relationships of DLSAPs, DLSAP-addresses, DLCEPs, DLCEP-addresses,
DLSEP-addresses and group DL-addresses . 19
Figure 2 – Basic structure of a DL-address . 38
Figure 3 – Basic structure of a sublink selector . 39
Figure 4 – DL-address alternative structures . 39
Figure 5 – Basic structure of MAC-addresses . 49
Figure 6 – Representation of a DL-address as a MAC-address . 49
Figure 7 – Linear relationships of sending and receiving DLCEP sequence-number
variables . 62
Figure 8 – DL-address alternative structures . 73
Figure 9 – SHORT DL-address field – alternative implicit structures . 74
Figure 10 – NODE DL-address field – implicit structure . 74
Figure 11 – State transition diagram for a DLCEP . 187
Figure 12 – Projection of the sending and receiving DLCEP sequence-number
variables of Figure 7 onto the cyclic sequence-number parameters of CA, CD, DT, ED
and RC DLPDUs, with consequent determination of required actions . 203
Figure 13 – State transitions of a DLE . 283
Figure 14 – Bridged network topology . 299
Figure 15 – Spanning tree representation . 300
Figure 16 – DLSDU transit delay, DLPDU lifetime and bridge forwarding delay . 304
Figure 17 – Forwarding and delivering a received DLPDU . 308
Figure 18 – Forwarding a locally-originated DLPDU . 309
Figure 19 – Republishing a DLSDU received from another link . 310
Figure 20 – Bridge architecture . 311
Figure 21 – Replacement for [IL] Fig 3-2  Bridge ports . 320
Figure 22 – Replacement for [IL] Fig 3-3  Bridge architecture . 321
Figure A.1 – Example of FCS generation . 366

Figure A.2 – Example of FCS syndrome checking on reception . 366
Figure C.1 – Gross structure of FC code points . 392
Figure C.2 [Figure 2] – Basic structure of a DL-address . 405
Figure C.3 [Figure 3] – Basic structure of a sublink selector . 405
Figure C.4 [Figure 4] – DL-address alternative structures . 405
Figure C.5 [Figure 5] – Basic structure of MAC-addresses . 405
Figure C.6 [Figure 6] – Representation of a DL-address as a MAC-address . 405

Table 1 – Link || node || selector addressing . 41
Table 2 – Link-local node || selector addressing . 43
Table 3 – Link-local node designators . 45
Table 4 – Node-local selector addressing . 46
Table 5 – Predefined flat non-local DL-addresses . 47
Table 6 – Predefined flat link-local DL-addresses . 48
Table 7 – Predefined node-local DL-addresses . 48
Table 8 – Correlation of DLPDUs with functional classes . 54
Table 9 – FCS length, polynomial and expected residual . 76
Table 10 – Summary structure of DLPDUs . 82
Table 11 – DLPDU restrictions based on dominant token . 83
Table 12 – Structure of EC DLPDUs . 83
Table 13 – Structure of DC DLPDUs . 86
Table 14 – Structure of RC DLPDUs . 88
Table 15 – Structure of CA DLPDUs . 90
Table 16 – Structure of CD DLPDUs . 96
Table 17 – Structure of ED DLPDUs . 103
Table 18 – Structure of DT DLPDUs . 111
Table 19 – Structure of SR DLPDUs . 119
Table 20 – Structure of CT DLPDUs . 121
Table 21 – Structure of TD DLPDUs . 123
Table 22 – Structure of RQ DLPDUs . 125
Table 23 – Structure of RR DLPDUs . 127
Table 24 – Structure of PN DLPDUs . 129
Table 25 – Structure of PR DLPDUs . 132
Table 26 – Structure of PT DLPDUs . 133
Table 27 – Structure of ES DLPDUs . 142
Table 28 – Structure of RT DLPDUs . 148
Table 29 – Structure of RI DLPDUs. 149
Table 30 – Structure of CL DLPDUs . 150
Table 31 – Structure of TL DLPDUs . 152
Table 32 – Structure of WK DLPDUs. 155
Table 33 – Structure of IDLE DLPDUs . 157
Table 34 – Assumed structure of undefined (spare) DLPDUs . 158
Table 35 – Assumed structure of RESERVED (NOT TO BE USED) DLPDUs . 160

– 6 – IEC 61158-4-1:2014 © IEC 2014
Table 36 – Structure of an EC DLPDU’s parameters . 161
Table 37 – EC-parameters: 1st octet . 161
Table 38 – EC-parameters: 2nd octet . 161
Table 39 – EC-parameters: 3rd and 4th octets . 162
Table 40 – EC-parameters: 5th and 6th octets . 162
Table 41 – EC-parameters: 7th octet . 163
Table 42 – EC-parameters: 8th octet . 163
Table 43 – EC-parameters: 9th and 10th octets . 164
Table 44 – EC-parameters: 11th octet . 164
Table 45 – EC-parameters: 12th octet . 165
Table 46 – EC-parameters: 13th and 14th octets . 165
Table 47 – DC-parameters and RC-parameters: 1st octet . 165
Table 48 – DC-parameters and RC-parameters: 2nd octet . 166
Table 49 – Disconnect reasons . 167
Table 50 – Reset reasons . 168
Table 51 – RC-parameters: 3rd octet . 168
Table 52 – RC-parameters: 4th octet . 168
Table 53 – Structure of connectionless-mode CA, CD, DT and ED DLPDUs. 169
Table 54 – Short format SD-parameters for connectionless transaction initiators . 170
Table 55 – Short format SD-parameters for connectionless responders . 170
Table 56 – Reply status for unitdata-acknowledgment and exchange-unitdata-reply DT
DLPDUs . 171
Table 57 – Structure of connection-oriented CA, CD, DT and ED DLPDUs . 173
Table 58 – Short format SD-parameters for DLCEP state . 174
Table 59 – Long format SD-parameters for DLCEP state: 1st octet . 174
Table 60 – Long format SD-parameters for DLCEP state: 2nd octet . 174
Table 61 – Long format SD-parameters for DLCEP state: 3rd octet . 175
Table 62 – Reply status for SR DLPDUs . 176
Table 63 – Short format SR-parameters . 176
Table 64 – Structure of TD-parameters . 177
Table 65 – Structure and encoding of the DL-time-quality measures . 177
Table 66 – Approximate numeric significance of the bits of seven-octet DL-time . 178
Table 67 – Approximate numeric significance of the bits of three-octet short time . 179
Table 68 – Structure of RQ-parameters . 179
Table 69 – Structure of RR-parameters . 179
Table 70 – Structure and encoding of the RR-time-quality measures . 180
Table 71 – Structure of PN-parameters . 181
Table 72 – PN-parameters: 1st octet . 181
Table 73 – PN-parameters: 2nd octet . 181
Table 74 – PN-parameters: 3rd and 4th octets . 181
Table 75 – PN-parameters: 5th octet . 182
Table 76 – PN-parameters: 6th octet . 182
Table 77 – Structure of DD-parameters . 182

Table 78 – Components of returned DL-time . 238
Table 79 – Time synchronization computation . 240
Table 80 – SPDU 1st octet: SPDU class, and protocol version or subclass . 248
Table 81 – Probe-response SPDU . 249
Table 82 – DL-protocol versions supported . 249
Table 83 – PR-SPDU: 3rd and 4th octets . 249
Table 84 – Node-activation SPDU . 251
Table 85 – Node-activation SPDU: 4th octet . 251
Table 86 – LAS-data-base-status SPDU . 252
Table 87 – LAS-data-base-status SPDU: 2nd octet . 252
Table 88 – Live-list- change SPDU . 252
Table 89 – DLE-status structure . 253
Table 90 – Live-list-detail SPDU . 254
Table 91 – DL-conformance-reply SPDU . 255
Table 92 – DL-protocol versions supported . 255
Table 93 – DL-conformance encoding (portion 1) . 255
Table 94 – DL-conformance encoding (portion 2) . 256
Table 95 – DL-conformance encoding (portion 3) . 256
Table 96 – DL-conformance encoding (portion 4) . 256
Table 97 – Link-basic-parameters-reply SPDU . 257
Table 98 – Link-master-parameters-reply SPDU . 258
Table 99 – Token-hold-time-request SPDU . 259
Table 100 – Token-hold-time-array SPDU . 259
Table 101 – Sequence element header encoding . 261
Table 102 – SHORT DL-address and duration sequence element . 261
Table 103 – LONG DL-address and duration sequence element . 262
Table 104 – Wakeup request sequence element . 263
Table 105 – Schedule-request SPDU . 264
Table 106 – Sequence type, schedule type and priority encoding . 264
Table 107 – Scheduling-completed SPDU . 266
Table 108 – Status and reason codes . 266
Table 109 – Cancel-schedule SPDU . 266
Table 110 – Schedule-cancelled SPDU . 267
Table 111 – Link-schedule . 268
Table 112 – Schedule-summary SPDU . 268
Table 113 – Subschedule-SPDU reference . 269
Table 114 – Subschedule SPDU . 270
Table 115 – Sequence Sub-SPDU . 271
Table 116 – Element-description . 271
Table 117 – Schedule-summary-request SPDU . 272
Table 118 – Subschedule-request SPDU . 273
Table 119 – Parameter-list element-header encoding . 273
Table 120 – Begin/end-of-list element . 274

– 8 – IEC 61158-4-1:2014 © IEC 2014
Table 121 – Continuation-of-list element . 274
Table 122 – SHORT DL-address list element . 274
Table 123 – LONG DL-address element . 275
Table 124 – DLSAP-address-characteristics element . 275
Table 125 – DLCEP-characteristics element . 276
Table 126 – Address-query SPDU . 276
Table 127 – Address-report SPDU . 277
Table 128 – Address-list-query SPDU . 278
Table 129 – DL-address selection criteria . 279
Table 130 – Address-list-reply SPDU . 280
Table 131 – Topology change notification BPDU format . 328
Table 132 – Configuration BPDU format . 328
Table 133 – Maximum permitted phase-tracking error in a DLE’s sense of DL-time at
the minimum requireable Time Distribution period . 336
Table C.1 – Generic assignment of FC code points . 393
Table C.2 – Individual assignment of FC code points . 394
Table C.3 – Reply status for SR DLPDUs . 397
Table C.4 – Reply status for unitdata-acknowledgment and exchange-unitdata-reply DT
DLPDUs . 398
Table C.5 – Approximate numeric significance of the bits of seven-octet DL-time . 403
Table C.6 – Approximate numeric significance of the bits of N(NT), A…A, and three-
octet C(NT) . 403
Table C.7 [Table 1] – Link || node || selector addressing . 406
Table C.8 [Table 2] – Link-local node || selector addressing . 406
Table C.9 [Table 5] – Predefined flat non-local DL-addresses . 407
Table C.10 [Table 6] – Predefined flat link-local DL-addresses . 407
Table C.11 [Table 3] – Link-local node designators . 408
Table C.12 [Table 4] – Node-local selector addressing . 408
Table C.13 [Table 7] – Predefined node-local DL-addresses . 408

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
INDUSTRIAL COMMUNICATION NETWORKS –
FIELDBUS SPECIFICATIONS –
Part 4-1: Data-link layer protocol specification –
Type 1 elements
FOREWORD
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