IEC 61158-4:2003

INTERNATIONAL IEC
STANDARD
61158-4
Third edition
2003-05
Digital data communications
for measurement and control –
Fieldbus for use in industrial
control systems –
Part 4:
Data link protocol specification

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INTERNATIONAL IEC
STANDARD 61158-4
Third edition
2003-05
Digital data communications
for measurement and control –
Fieldbus for use in industrial
control systems –
Part 4:
Data link protocol specification

© IEC 2003 – Copyright - all rights reserved
No part of this publication may be reproduced or utilized in any form or by any means, electronic or
mechanical, including photocopying and microfilm, without permission in writing from the publisher.
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Telephone: +41 22 919 02 11 Telefax: +41 22 919 03 00 E-mail: inmail@iec.ch Web: www.iec.ch
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Commission Electrotechnique Internationale XH
International Electrotechnical Commission
Международная Электротехническая Комиссия
For price, see current catalogue

– 2 – 61158-4  IEC:2003(E)
CONTENTS
FOREWORD.24

0 Introduction.27

0.1 General .27

0.2 Nomenclature for references within this standard .27

1 Scope and object .29

1.1 Overview .29

1.2 Specifications.30

1.3 Procedures.32
1.4 Applicability.32
1.5 Conformance.32
2 Normative references.32
3 Terms and definitions.33
3.1 Reference model terms and definitions.33
3.2 Service convention terms and definitions.35
3.3 Common terms and definitions .36
3.4 Type 1: Additional terms and definitions .39
3.5 Type 2: Additional terms and definitions .45
3.6 Type 3: Additional terms and definitions .52
3.7 Type 4: Additional terms and definitions .54
3.8 Type 5: Additional terms and definitions .55
3.9 Type 6: Additional terms and definitions .55
3.10 Type 7: Additional terms and definitions .65
3.11 Type 8: Additional terms and definitions .67
4 Symbols and abbreviations .69
4.1 Common symbols and abbreviations .69
4.2 Type 1: Additional symbols and abbreviations .69
4.3 Type 2: Additional symbols and abbreviations .73
4.4 Type 3: Additional symbols and abbreviations .74
4.5 Type 4: Additional symbols and abbreviations .78
4.6 Type 5: Additional symbols and abbreviations .79
4.7 Type 6: Additional symbols and abbreviations .79

4.8 Type 7: Additional symbols and abbreviations .80
4.9 Type 8: Additional symbols and abbreviations .81
5 DL-protocol elements common to multiple DL-protocol Types .84
5.1 Frame check sequence.84
6 Type 1: Overview of the DL-protocol .88
6.1 Three-level model of the DLL .88
6.2 Service provided by the DLL.91
6.3 Structure and definition of DL-addresses .97
6.4 Service assumed from the PhL .109
6.5 Functions of the DLL .112
6.6 Functional classes.114
6.7 Local parameters, variables, counters, timers and queues.116

61158-4  IEC:2003(E) – 3 –
7 Type 1: General structure and encoding of PhIDUs and DLPDUs, and related

elements of procedure .130

7.1 PhIDU structure and encoding.130

7.2 Common DLPDU structure, encoding and elements of procedure .130

8 Type 1: DLPDU-specific structure, encoding and elements of procedure.139

8.1 Establish Connection (EC) DLPDU .141

8.2 Disconnect Connection (DC) DLPDU .143

8.3 Reset Connection (RC) DLPDU .146

8.4 Compel Acknowledgement (CA) DLPDU.147

8.5 Compel Data (CD) DLPDU .154
8.6 Exchange Data (ED) DLPDU .162
8.7 Data (DT) DLPDU.170
8.8 Status Response (SR) DLPDU .178
8.9 Compel Time (CT) DLPDU .181
8.10 Time Distribution (TD) DLPDU.182
8.11 Round-Trip-Delay Query (RQ) DLPDU.184
8.12 Round-Trip-Delay Reply (RR) DLPDU .186
8.13 Probe Node DL-address (PN) DLPDU.188
8.14 Probe Response (PR) DLPDU .191
8.15 Pass Token (PT) DLPDU .192
8.16 Execute Sequence (ES) DLPDU .201
8.17 Return Token (RT) DLPDU .208
8.18 Request Interval (RI) DLPDU.209
8.19 Claim LAS (CL) DLPDU.210
8.20 Transfer LAS (TL) DLPDU .212
8.21 Wakeup (WK) DLPDU.216
8.22 Idle (IDLE) DLPDU .217
8.23 Spare DLPDUs .218
8.24 Reserved (not to be used) DLPDUs .220
9 Type 1: DLPDU-parameter structure and encoding .221
9.1 Structure and encoding of EC-PARAMETERS .221
9.2 Structure and encoding of DC-PARAMETERS .226
9.3 Structure and encoding of RC-PARAMETERS .226
9.4 Structure and encoding of SD-Parameters.228

9.5 Structure and encoding of SR-parameters .235
9.6 Structure and encoding of TD-parameters .237
9.7 Structure and encoding of RQ-parameters.239
9.8 Structure and encoding of RR-parameters .240
9.9 Structure and encoding of PN-parameters .240
9.10 Structure and encoding of DD-parameters .242
10 Type 1: DL-service elements of procedure .243
10.1 Operation of the DL(SAP)-address, buffer and queue management services .243
10.2 Operation of the connection-mode services .247
10.3 Operation of the connectionless-mode services.288
10.4 Operation of the scheduling guidance services.300

– 4 – 61158-4  IEC:2003(E)
11 Type 1: DL-support subprotocol .310

11.1 Scope 310
11.2 Overview of LAS operation .310

11.3 DL-support subprotocol definition .311

11.4 Elements of Procedures for receiving SPDUs .345

12 Type 1: Other DLE elements of procedure.347

12.1 DLE initialization .347

12.2 LAS behavior and operation .351

12.3 DL-support operation.358

12.4 DL-bridge elements of procedure and bridge sub-protocol .363
12.5 DL-management-information .393
12.6 Implementation profiles .398
13 Type 1: PICS proforma.404
13.1 Introduction .404
13.2 Scope. 404
13.3 Normative references .404
13.4 Definitions .404
13.5 Abbreviations .404
13.6 Conformance.405
13.7 Instructions .405
13.8 Identification.406
13.9 Implementation profile .407
13.10 Major low-level capabilities.411
13.11 Major high-level capabilities .425
14 Type 2: Overview of the DL-protocol .434
14.1 General .434
14.2 Services provided by the DL.436
14.3 Structure and definition of DL-addresses .437
14.4 Services assumed from the PhL .439
14.5 Functional classes.441
15 Type 2: General structure and encoding of PhIDUs and DLPDUs and related
elements of procedure .442
15.1 Overview .442

15.2 Media access procedure.442
15.3 DLPDU structure and encoding .445
15.4 Lpacket components.447
15.5 DLPDU procedures.449
15.6 Summary of DLL support services and objects .450
16 Type 2: Specific DLPDU structure, encoding and procedures .453
16.1 Modeling language .453
16.2 DLS user services .455
16.3 Generic Tag Lpacket .461
16.4 Moderator Lpacket .461
16.5 Time distribution Lpacket.463
16.6 UCMM Lpacket.465
16.7 Keeper UCMM Lpacket.465
16.8 TUI Lpacket.466

61158-4  IEC:2003(E) – 5 –
16.9 Link parameters Lpacket and tMinus Lpacket .467

16.10 I’m alive Lpacket .469

16.11 Ping Lpackets.470

16.12 WAMI Lpacket .472

16.13 Debug Lpacket .472

17 Type 2: Objects for station management .474

17.1 General .474

17.2 ControlNet object .475

17.3 Keeper object .485

17.4 Scheduling object .508
17.5 TCP/IP interface object .517
17.6 Ethernet link object.524
18 Type 2: Other DLE elements of procedure .529
18.1 Network Attachment Monitor (NAM).529
18.2 Calculating link parameters .536
19 Type 2: Detailed specification of DL components .544
19.1 General .544
19.2 Access Control Machine (ACM) .544
19.3 TxLLC. 561
19.4 RxLLC. 565
19.5 Transmit Machine (TxM).568
19.6 Receive Machine (RxM).571
19.7 Serializer.577
19.8 Deserializer .578
19.9 DLL management .579
20 Type 3: Overview of the DL-protocol .582
20.1 General .582
20.2 Overview of the medium access control and transmission protocol .582
20.3 Transmission modes and DL-entity.583
20.4 Service assumed from the PhL .588
20.5 Operational elements .590
20.6 Cycle and system reaction times .605
21 Type 3: General structure and encoding of DLPDUs, and related elements of

procedure . 609
21.1 DLPDU granularity.609
21.2 Length octet (LE, LEr) .610
21.3 Address octet .610
21.4 Control octet (FC).613
21.5 DLPDU content error detection.616
21.6 DATA_UNIT .617
21.7 Error control procedures.618
22 Type 3: DLPDU-specific structure, encoding and elements of procedure .619
22.1 DLPDUs of fixed length with no data field .619
22.2 DLPDUs of fixed length with data field.621
22.3 DLPDUs with variable data field length.622
22.4 Token DLPDU .624

– 6 – 61158-4  IEC:2003(E)
22.5 ASP DLPDU .625

22.6 SYNCH DLPDU .625

22.7 Time Event (TE) DLPDU.625

22.8 Clock Value (CV) DLPDU .625

22.9 Transmission procedures .626

23 Type 3: Other DLE elements of procedure.629

23.1 DL-entity initialization .629

23.2 States of the media access control of the DL-entity .629

23.3 Clock synchronization protocol .635

24 Type 4: Data Link Protocol Definition .640
24.1 Overview of the DL-protocol .640
24.2 General structure and encoding of PhIDUs and DLPDUs, and related
elements of procedure.651
24.3 DLPDU-specific structure, encoding and elements of procedure .657
24.4 DL-service elements of procedure .661
24.5 Route mechanism.664
24.6 Link-access system .668
24.7 Local variables, counters and queues.668
25 Type 5: .671
26 Type 6: Connection-oriented DL-protocol and related matters .673
26.1 Connection mode data transfer using TDMA principles .673
26.2 Bus access and data transmission.673
26.3 Overview of bus synchronization .675
26.4 Connection mode data transfer.678
26.5 DLM-connectionless service .706
26.6 Other real-time services .720
26.7 Bridge architecture and operation.724
26.8 Bus configuration .726
26.9 Conformance.736
27 Type 6: MAC elements of procedure .738
27.1 Procedures related to bus startup and bus operation .738
27.2 Medium access control (MAC) .743

28 Type 7: Overview of the DL-protocol .746
28.1 Overall description of medium allocation .746
28.2 Types of entities .748
28.3 Addressing .751
28.4 Flow control.757
28.5 Graphical representation .759
29 Type 7: General structure and encoding of PhIDUs and DLPDUs and related
elements of procedure .760
29.1 DLPDU formats and components.760
29.2 Description of each DLPDU component .760
29.3 PhIDU structure and encoding.762
29.4 Common DLPDU structure, encoding and elements of procedure .763
29.5 Valid DLPDU types.763
29.6 DLL timers.765

61158-4  IEC:2003(E) – 7 –
30 Type 7: DLPDU-specific structure, encoding and element of procedure.771

30.1 General .771

30.2 Buffer read .771

30.3 Buffer write.771

30.4 Buffer transfer .771

30.5 Specified explicit request.772

30.6 Free explicit request.778

30.7 Messaging.781

30.8 Acknowledged messaging .786

30.9 Numbering of acknowledged messages .790

30.10 Behavior with mismatched parameters .792
31 Type 7: DL-service elements of procedure, interfaces and conformance .795
31.1 General .795
31.2 Producer/consumer entity.795
31.3 Protocol elements by service.798
31.4 Bus arbitrator operation.806
31.5 B r i d g e s . 8 1 3
31.6 Interfaces .820
31.7 Conformance.822
32 Type 8: DL-protocol .825
32.1 Overview .825
32.2 DL-service Interface (DLI) .825
32.3 Peripherals data link (PDL).829
32.4 Basic Link Layer (BLL) .864
32.5 Medium Access Control (MAC) .880
32.6 Peripherals network management for layer 2 (PNM2) .912
32.7 Parameters and monitoring times of the DLL .920
Annex A (informative) – Types 1, 2, 3 (synchronous), 5 (first FCS), 6, 7 and 8:
Exemplary FCS implementations.926
Annex B (informative) – Type 1: Formal protocol finite state machines.928
B.1 Basic reception and transmission FSMs .928
B.2 FSMs for DLCs.940
B.3 FSMs for scheduling.946

B.4 FSMs for bridges .946
Annex C (informative) – Type 1: DLPDU and DL-addressing short-form summaries .947
C.1 Fields used in short-form summaries .947
C.2 DLPDU short-form summary grouped by function .949
C.3 DLPDU short-form summary in alphabetic order of DLPDU names .951
C.4 DLPDU short-form summary in alphabetic order of DLPDU acronyms.952
C.5 DLPDU FC code-point assignment matrix – overview and detail .953
C.6 SD-parameters (status and data-description parameters) of CA, CD, ED and
DT DLPDUs.956
C.7 EC parameters of EC DLPDUs .959
C.8 Parameters of DC and RC DLPDUs.961
C.9 Parameters of TD, RQ and RR DLPDUs .963
C.10 Parameters of PN, PT, ES and RI DLPDUs .965
C.11 Addressing summary extracted from figures and tables of 6.3 .967

– 8 – 61158-4  IEC:2003(E)
Annex D (informative) – Type 2: Indicators and Switches.971

D.1 Purpose.971

D.2 General indicator requirements.971

D.3 Common indicator requirements .971

D.4 Module status indicator .972

D.5 Network status indicators .972

D.6 Switches.975

Annex E (normative) – Type 3: DL-Protocol state machines.977

E.1 Overall structure.977

E.2 Variation of state machines in different devices .979
E.3 DL Data Resource .979
E.4 FLC / DLM.984
E.5 MAC . 1009
E.6 SRU . 1038
Annex F (informative) – Type 3: Exemplary token procedure and message transfer
periods. 1056
F.1 Procedure of token passing . 1056
F.2 Examples for token passing procedure . 1057
F.3 Examples for message transfer periods – asynchronous transmission . 1061
F.4 Examples for message transfer periods – synchronous transmission. 1062
Annex G (informative) – Type 7: Object Modeling . 1063
G.1 Modeling of the IDENTIFIER object . 1063
G.2 Description of the IDENTIFIER object attributes . 1064
G.3 Modeling of the QUEUE object . 1068
G.4 Description of the QUEUE object attributes . 1068
G.5 Modeling of the BUFFER object. 1069
G.6 Description of the BUFFER object attributes. 1069
Annex H (informative) – Type 7: Topology of multi-segment DL-subnetwork . 1070
H.1 Introduction . 1070
H.2 Global specification . 1070
H.3 Local specification. 1071
H.4 Properties. 1071
H.5 Methods . 1072

Annex I (informative) – Type 7: Management of transmission errors . 1075
I.1 Transmission of RP_DAT_XX . 1075
I.2 Transmission of a free RP_RQ(1/2) . 1075
I.3 Transmission of the specified RP_RQ1. 1076
I.4 Transmission of RP_MSG_NOACK. 1077
I.5 Transmission of RP_MSG_ACK. 1079
Annex J (informative) – Type 8: Implementation possibilities of definite PNM2
functions . 1082
J.1 Acquiring the current configuration . 1082
J.2 Comparing the acquired and stored configurations prior to a DL-subnetwork
error . 1085
BIBLIOGRAPHY . 1092
INDEX . 1094

61158-4  IEC:2003(E) – 9 –
Figure 1 – Relationship of IEC 61158-4 to other fieldbus layers and to users of the

fieldbus Data Link service .27

Figure 2 – Relationships of DLSAPs, DLSAP-addresses and group DL-addresses .38

Figure 3 – Relationships of DLCEPs and DLCEP-addresses to DLSAPs, DLSAP-

addresses and group DL-addresses.40

Figure 4 – Basic Structure of a DL-address.98

Figure 5 – Basic Structure of a Sublink Selector .98

Figure 6 – DL-address Alternative Structures.99

Figure 7 – Basic Structure of MAC-addresses.109
Figure 8 – Representation of a DL-address as a MAC-address .109
Figure 9 – Linear relationships of sending and receiving DLCEP sequence-number
variables.122
Figure 10 – DL-address alternative structures.133
Figure 11 – SHORT DL-address field – alternative implicit structures.133
Figure 12 – NODE DL-address field – implicit structure .134
Figure 13 – State transition diagram for a DLCEP.247
Figure 14 – Projection of the sending and receiving DLCEP sequence-number variables
of Figure 9 onto the cyclic sequence-number parameters of CA, CD, DT, ED and
RC DLPDUs, with consequent determination of required actions.264
Figure 15 – State transitions of a DLE .347
Figure 16 – Bridged network topology.364
Figure 17 – Spanning tree representation .365
Figure 18 – DLSDU transit delay, DLPDU lifetime and bridge forwarding delay.369
Figure 19 – Forwarding and delivering a received DLPDU .373
Figure 20 – Forwarding a locally-originated DLPDU .374
Figure 21 – Republishing a DLSDU received from another link .375
Figure 22 – Bridge architecture.376
Figure 23 – Replacement for [IL] Fig 3-2  Bridge ports .385
Figure 24 – Replacement for [IL] Fig 3-3  Bridge architecture .386
Figure 25 – Data Link Layer internal architecture .435
Figure 26 – Basic Structure of a MAC ID address .437
Figure 27 – Basic Structure of a Generic tag address .437
Figure 28 – Basic Structure of a Fixed tag address .438

Figure 29 – M_symbols and Manchester encoding at 5 MHz (informative).439
Figure 30 – NUT structure.443
Figure 31 – Media access during scheduled time .443
Figure 32 – Media access during unscheduled time .
...