IEC 61158-4:2000

INTERNATIONAL
IEC
STANDARD
61158-4
Second edition
2000-01
Digital data communications for
measurement and control –
Fieldbus for use in industrial control systems –
Part 4:
Data Link protocol specification

Reference number
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* See web site address on title page.

INTERNATIONAL IEC
STANDARD 61158-4
Second edition
2000-01
Digital data communications for
measurement and control –
Fieldbus for use in industrial control systems –
Part 4:
Data Link protocol specification

© IEC 2000 – 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.
International Electrotechnical Commission 3, rue de Varembé Geneva, Switzerland
Telefax: +41 22 919 0300 e-mail: inmail@iec.ch IEC web site http://www.iec.ch
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International Electrotechnical Commission

For price, see current catalogue

– 2 – 61158-4 © IEC:2000(E)
CONTENTS
Page
FOREWORD .28

INTRODUCTION . 30

Clause
1 Scope and object . 31

1.1 Specifications . 32

1.2 Procedures . 34
1.3 Applicability. 34
1.4 Conformance . 34
2 Normative references . 35
2.1 Common normative references. 35
2.2 Type 1: additional normative references . 35
2.3 Type 2: additional normative references . 36
2.4 Type 3: additional normative references . 36
2.5 Type 4: additional normative references . 36
2.6 Type 5: additional normative references . 36
2.7 Type 6: additional normative references . 36
2.8 Type 7: additional normative references . 36
2.9 Type 8: additional normative references . 37
3 Definitions. 38
3.1 Reference model definitions . 38
3.2 Service convention definitions . 40
3.3 Common terms and definitions . 41
3.4 Type 1: additional terms and definitions. 42
3.5 Type 2: additional terms and definitions. 51
3.6 Type 3: additional terms and definitions. 58
3.7 Type 4: additional terms and definitions. 60
3.8 Type 5: additional terms and definitions. 61
3.9 Type 6: additional terms and definitions. 61
3.10 Type 7: additional terms and definitions. 71
3.11 Type 8: additional terms and definitions. 74
4 Symbols and abbreviations. 75

4.1 Common symbols and abbreviations . 75
4.2 Type 1: additional symbols and abbreviations . 75
4.3 Type 2: additional symbols and abbreviations . 79
4.4 Type 3: additional symbols and abbreviations . 80
4.5 Type 4: additional symbols and abbreviations . 84
4.6 Type 5: additional symbols and abbreviations . 84
4.7 Type 6: additional symbols and abbreviations . 84
4.8 Type 7: additional symbols and abbreviations . 86
4.9 Type 8: additional symbols and abbreviations . 87
5 DL-protocol elements common to multiple DL-protocl Types . 90
5.1 Frame check sequence . 90
6 Type 1: Overview of the DL-protocol. 94
6.1 Three-level model of the DLL . 94

61158-4 © IEC:2000(E) – 3 –
6.2 Service provided by the DLL. 97

6.3 Structure and definition of DL-addresses . 104

6.4 Service assumed from the PhL. 116

6.5 Functions of the DLL . 119

6.6 Functional classes . 121

6.7 Local parameters, variables, counters, timers and queues . 123

7 Type 1: General structure and encoding of PhIDUs and DLPDUs, and related elements

of procedure. 138

7.1 PhIDU structure and encoding. 138

7.2 Common DLPDU structure, encoding and elements of procedure . 139

8 Type 1: DLPDU-specific structure, encoding and elements of procedure. 148
8.1 Establish Connection (EC) DLPDU . 150
8.2 Disconnect Connection (DC) DLPDU . 152
8.3 Reset Connection (RC) DLPDU . 155
8.4 Compel Acknowledgement (CA) DLPDU. 157
8.5 Compel Data (CD) DLPDU . 164
8.6 Exchange Data (ED) DLPDU . 172
8.7 Data (DT) DLPDU . 182
8.8 Status Response (SR) DLPDU . 191
8.9 Compel Time (CT) DLPDU . 194
8.10 Time Distribution (TD) DLPDU. 196
8.11 Round-Trip-Delay Query (RQ) DLPDU. 198
8.12 Round-Trip-Delay Reply (RR) DLPDU. 200
8.13 Probe Node DL-address (PN) DLPDU. 202
8.14 Probe Response (PR) DLPDU . 205
8.15 Pass Token (PT) DLPDU. 206
8.16 Execute Sequence (ES) DLPDU . 216
8.17 Return Token (RT) DLPDU. 224
8.18 Request Interval (RI) DLPDU. 225
8.19 Claim LAS (CL) DLPDU. 226
8.20 Transfer LAS (TL) DLPDU. 228
8.21 Wakeup (WK) DLPDU. 232
8.22 Idle (IDLE) DLPDU . 233
8.23 Spare DLPDUs. 235
8.24 Reserved (not to be used) DLPDUs . 236

9 Type 1: DLPDU-parameter structure and encoding . 238
9.1 Structure and encoding of EC-PARAMETERS . 238
9.2 Structure and encoding of DC-PARAMETERS . 243
9.3 Structure and encoding of RC-PARAMETERS . 244
9.4 Structure and encoding of SD-Parameters. 246
9.5 Structure and encoding of SR-parameters . 254
9.6 Structure and encoding of TD-parameters . 254
9.7 Structure and encoding of RQ-parameters. 257
9.8 Structure and encoding of RR-parameters . 258
9.9 Structure and encoding of PN-parameters . 259
9.10 Structure and encoding of DD-parameters . 260
10 Type 1: DL-service elements of procedure. 262
10.1 Operation of the DL(SAP)-address, buffer and queue management services. 262
10.2 Operation of the connection-mode services . 266

– 4 – 61158-4 © IEC:2000(E)
10.3 Operation of the connectionless-mode services . 315

10.4 Operation of the scheduling guidance services . 329

11 Type 1: DL-support subprotocol. 341

11.1 Scope . 341

11.2 Overview of LAS operation . 341

11.3 DL-support subprotocol definition . 342

11.4 Elements of Procedures for receiving SPDUs . 379

12 Type 1: Other DLE elements of procedure . 381

12.1 DLE initialization . 381

12.2 LAS behavior and operation . 386
12.3 DL-support operation. 395
12.4 DL-bridge elements of procedure and bridge sub-protocol . 401
12.5 DL-management-information . 433
12.6 Implementation profiles . 437
13 Type 1: PICS proforma. 444
13.1 Introduction. 444
13.2 Scope . 444
13.3 Normative references. 444
13.4 Definitions. 444
13.5 Abbreviations . 444
13.6 Conformance . 445
13.7 Instructions . 445
13.8 Identification . 446
13.9 Implementation profile. 446
13.10 Major low-level capabilities. 451
13.11 Major high-level capabilities . 465
14 Type 2: Overview of the DL-protocol. 476
14.1 General. 476
14.2 Services provided by the DL . 478
14.3 Structure and definition of DL-addresses . 479
14.4 Services assumed from the PhL . 481
14.5 Functional classes . 483
15 Type 2: General structure and encoding of PhIDUs and DLPDUs and related elements of
procedure . 484
15.1 Overview. 484

15.2 Media access procedure . 484
15.3 Mframe structure and encoding . 488
15.4 Lpacket components . 489
15.5 General Mframe procedures. 491
15.6 Summary of DLL support services and objects . 493
16 Type 2: Specific DLPDU structure, encoding and procedures. 495
16.1 Modeling language . 495
16.2 Use of DLL- prefix . 496
16.3 DLS user services . 497
16.4 Generic Tag Lpacket. 503
16.5 Moderator Lpacket . 503
16.6 Time distribution Lpacket . 504
16.7 UCMM Lpacket . 507
16.8 Keeper UCMM Lpacket . 507

61158-4 © IEC:2000(E) – 5 –
16.9 TUI Lpacket . 508

16.10 Link parameters Lpacket and tMinus Lpacket . 509

16.11 I’m alive Lpacket . 510

16.12 Ping Lpackets . 512

16.13 WAMI Lpacket . 513

17 Type 2: Objects for station management. 515

17.1 General. 515

17.2 ControlNet object . 516

17.3 Keeper object. 526

17.4 Scheduler object . 549
18 Type 2: Other DLE elements of procedure . 561
18.1 Network Attachment Monitor (NAM). 561
18.2 Calculating link parameters . 567
19 Type 2: Detailed specification of DL components . 575
19.1 Access Control Machine (ACM) . 575
19.2 TxLLC. 592
19.3 RxLLC . 596
19.4 Transmit Machine (TxM) . 599
19.5 Receive Machine (RxM) . 602
19.6 Serializer . 608
19.7 Deserializer. 609
19.8 DLL management. 610
20 Type 3: Overview of the DL-protocol. 613
20.1 General. 613
20.2 Overview of the medium access control and transmission protocol . 613
20.3 Transmission modes and DL-entity. 614
20.4 Service assumed from the PhL. 621
20.5 Timer operation. 622
20.6 Cycle and system reaction times . 634
21 Type 3: General structure and encoding of PhIDUs and DLPDUs, and related elements of
procedure . 637
21.1 Overview. 637
21.2 Frame character. 637
21.3 Length octet (LE, LEr) . 638
21.4 Address octet. 639

21.5 Control octet (FC) . 641
21.6 Frame check sequence (FCS) . 645
21.7 Data field (DATA_UNIT) . 646
21.8 Error control procedures. 648
22 Type 3: DLPDU-specific structure, encoding and elements of procedure . 650
22.1 Overview of frame correlation to station types. 650
22.2 Frames of fixed length with no data field. 650
22.3 Frames of fixed length with data field . 653
22.4 Frames with variable data field length. 654
22.5 Token frame . 657
22.6 Transmission procedures . 658
23 Type 3: Other DLE elements of procedure . 661
23.1 DL-entity initialization . 661
23.2 States of the media access control of the DL-entity. 661

– 6 – 61158-4 © IEC:2000(E)
24 Type 4: Data Link Protocol Definition . 667

24.1 Overview of the DL-protocol . 667

24.2 General structure and encoding of PhIDUs and DLPDUs, and related elements of
procedure . 678

24.3 DLPDU-specific structure, encoding and elements of procedure . 685

24.4 DL-service elements of procedure . 689

24.5 Route mechanism . 692

24.6 Link-access system. 696

24.7 Local variables, counters and queues. 697

25 Type 5:  . 699

26 Type 6: Overview of the Connection Oriented Data Transfer, Time and Coordination
DL-Protocol. 701
26.1 Connection Mode Data Transfer using Time Division Multiple Access (TDMA)
Principles. 701
26.2 Bus Access and Data Transmission. 701
26.3 Other Real-time services. 703
26.4 Overview of Bus Synchronization. 705
26.5 Overview of Connection mode features . 707
26.6 Overview of Connectionless mode. 716
26.7 Overview of Node Types and Access Roles . 720
27 Type 6: Elements of procedure. 721
27.1 Common procedures for data transmission and reception. 721
27.2 Connection mode procedures for DLSDU transfers. 724
27.3 Procedures related to Bus Startup and Bus Operation . 726
27.4 Procedures used in sequencing and synchronizing the Bus-State Machines of all
DLEs. 729
28 Type 7: Overview of the DL-protocol. 733
28.1 Overall description of medium allocation. 733
28.2 Types of entities. 735
28.3 Addressing. 740
28.4 Flow control . 747
28.5 Graphical representation . 749
29 Type 7: General structure and encoding of PhIDUs and DLPDUs and related elements of
procedure . 750
29.1 DLPDU formats and components. 750
29.2 Description of each DLPDU component . 750
29.3 PhIDU structure and encoding. 752
29.4 Common DLPDU structure, encoding and elements of procedure . 753
29.5 Valid DLPDU types. 753
29.6 DLL timers . 756
30 Type 7: DLPDU-Specific structure, encoding and element of procedure . 761
30.1 Buffer read. 761
30.2 Buffer Write . 761
30.3 Buffer transfer. 762
30.4 Specified Explicit Transfer. 763
30.5 Free Explicit request . 768
30.6 Messaging . 771
30.7 Acknowledged messaging . 776
30.8 Numbering of acknowledged messages. 780

61158-4 © IEC:2000(E) – 7 –
30.9 Behavior with mismatched parameters . 782

31 Type 7: DL-Service elements of procedure, interfaces and conformance. 785

31.1 Producer/consumer entity. 785

31.2 Protocol elements by service. 788

31.3 Bus Arbitrator operation . 797

31.4 Bridges . 805

31.5 Interfaces. 812

31.6 Conformance . 814

32 Type 8: DL-protocol. 818

32.1 Overview. 818
32.2 Data Link Layer Interface (DLI). 818
32.3 Peripherals Data Link (PDL) . 823
32.4 Basic Link Layer (BLL) . 860
32.5 Medium Access Control (MAC). 878
32.6 Peripherals Network Management of the Layer 2 (PNM2) . 911
32.7 Parameters and monitoring times of the DLL . 919
Annex A (informative) – Types 1, 2, 3 (synchronous), 5 (first FCS), 6, 7 and 8:  Exemplary
FCS implementations . 925
Annex B (informative) – Type 1: Formal protocol finite state machines . 927
B.1 Basic reception and transmission FSMs . 927
B.2 FSMs for DLCs . 939
B.3 FSMs for scheduling . 945
B.4 FSMs for bridges. 945
Annex C (informative) – Type 1: DLPDU and DL-addressing short-form summaries. 946
C.1 Fields used in short-form summaries. 946
C.2 DLPDU short-form summary grouped by function . 948
C.3 DLPDU short-form summary in alphabetic order of DLPDU names. 950
C.4 DLPDU short-form summary in alphabetic order of DLPDU acronyms . 951
C.5 DLPDU FC code-point assignment matrix – overview and detail. 952
C.6 SD-parameters (status and data-description parameters) of CA, CD, ED and DT
DLPDUs. 955
C.7 EC parameters of EC DLPDUs . 958
C.8 Parameters of DC and RC DLPDUs. 960
C.9 Parameters of TD, RQ and RR DLPDUs . 962
C.10 Parameters of PN, PT, ES and RI DLPDUs . 964

C.11 Addressing summary extracted from figures and tables of 6.3. 966
Annex D (informative) – Type 2: DLPDU and DL-addressing short-form summaries. 970
D.1 Structure and definition of DL-addresses . 970
D.2 MAC ID address. 970
Annex E (informative) – Type 2: PhL interface considerations . 972
E.1 Data Link to PhL interface , additional requirements . 972
E.2 PhL requirements. 972
Annex F (informative) – Type 2: Indicators and Switches. 974
F.1 Purpose . 974
F.2 General indicator requirements . 974
F.3 Common indicator requirements. 974
F.4 Module status indicator . 975
F.5 Network status indicators . 975
F.6 Switches . 978

– 8 – 61158-4 © IEC:2000(E)
Annex G (informative) – Type 3: Exemplary token procedure and message cycles. 980

G.1 Procedure of token passing. 980

G.2 Examples for Token Passing procedure. 981

G.3 Examples for message cycles – asynchronous transmission. 984

G.4 Examples for message cycles – synchronous transmission. 986

Annex H (informative) – Type 3: PhL Considerations. 988

H.1 Normative references. 988

H.2 Data transmission (Ph-media, Ph-layer). 988

H.3 Electrical characteristics. 989

H.4 Connector technique, mechanical and electrical specifications. 990
H.5 Transmission method. 994
Annex I (Informative) – Type 6: Media Independent PhL. 995
I.1 Additional definitions . 995
I.2 Additional definitions . 996
I.3 Media Independent Ph layer . 996
Annex J (Informative) – Type 6: RS-485 Wire – Media dependent PhL .1012
J.1 Normative references.1012
J.2 Transmission method.1012
Annex K (informative) – Type 7: Object Modeling .1019
K.1 Modeling of the IDENTIFIER object .1019
K.2 Description of the IDENTIFIER object attributes .1019
K.3 Modeling of the QUEUE object .1024
K.4 Description of the QUEUE object attributes .1024
K.5 Modeling of the BUFFER object.1025
K.6 Description of the BUFFER object attributes .1025
Annex L (informative) – Type 7: Topology of multi-segment DL-subnetwork.1026
L.1 Introduction.1026
L.2 Global Specification .1026
L.3 Local Specification .1027
L.4 Properties .1028
L.5 Methods.1028
Annex M (informative) – Type 7: Management of transmission errors .1032
M.1 Transmission of RP_DAT_XX.1032
M.2 Transmission of RP_RQ(1/2) FREE.1032

M.3 Transmission of the SPECIFIED RP_RQ1 .1033
M.4 Transmission of RP_MSG_NOACK .1034
M.5 Transmission of RP_MSG_ACK .1036
Annex N (informative) – Type 8: Implementation possibilities of definite PNM2 functions .1039
N.1 Acquiring the current configuration .1039
N.2 Comparing the acquired and stored configurations prior to a DL-subnetwork
error .1042
Annex O (informative) – Type 8: PhL Considerations.1049
O.1 Normative References.1049
O.2 PhL.1049
O.3 Peripherals Network Management of the Layer 1 (PNM1) .1049
Bibliography .1052
Index.1053

61158-4 © IEC:2000(E) – 9 –
Figures
Page
Figure 1 – Relationship of IEC 61158-4 to other Fieldbus layers and to users of the

Fieldbus Data Link Service 30
Figure 2 – Relationships of DLSAPs, DLSAP-addresses and group DL-addresses 42

Type 1
Figure 3 – Relationships of DLCEPs and DLCEP-addresses to DLSAPs, DLSAP-

addresses and group DL-addresses 44
Figure 4 – Basic Structure of a DL-address 104
Figure 5 – Basic Structure of a Sublink Selector 105
Figure 6 – DL-address Alternative Structures 105
Figure 7 – Basic Structure of MAC-addresses 116
Figure 8 – Representation of a DL-address as a MAC-address 116
Figure 9 – Linear relationships of sending and receiving DLCEP sequence-number
variables 130
Figure 10 – DL-address alternative structures 141
Figure 11 – SHORT DL-address field – alternative implicit structures 141
Figure 12 – NODE DL-address field – implicit structure 142
Figure 13 – State transition diagram for a DLCEP 267
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 287
Figure 15 – State transitions of a DLE 382
Figure 16 – Bridged Network Topology 402
Figure 17 – Spanning Tree Representation 402
Figure 18 – DLSDU transit delay, DLPDU lifetime and bridge forwarding delay 407

Figure 19 – Forwarding and delivering a received DLPDU 412
Figure 20 – Forwarding a locally-originated DLPDU 412
Figure 21 – Republishing a DLSDU received from another link 413
Figure 22 – Bridge architecture 415
Figure 23 – Replacement for [IL] Fig 3-2  Bridge ports 425
Figure 24 – Replacement for [IL] Fig 3-3  Bridge architecture 425
Type 2
Figure 25 – Data Link Layer internal architecture 477
Figure 26 – Basic Structure of a MAC ID address 479

– 10 – 61158-4 © IEC:2000(E)
Figure 27 – Basic Structure of a Generic tag address 479

Figure 28 – Basic Structure of a Fixed tag address 480

Figure 29 – M_symbols and Manchester encoding at 5MHz (informative) 481

Figure 30 – NUT structure 485
Figure 31 – Media access during scheduled time 486

Figure 32 – Media access during unscheduled time 487

Figure 33 – Mframe format 488
Figure 34 – Aborting an Mframe during transmission 489
Figure 35 – Lpacket format 490
Figure 36 – Generic tag Lpacket format 491
Figure 37 – Fixed tag Lpacket format 491
Figure 38 – goodness parameter of TimeDist_unit 505
Figure 39 – Example I’m alive processing algorithm 512
Figure 40 – Keeper CRC algorithm 532
Figure 41 – Keeper object Power Up State Diagram 545
Figure 42 – Keeper object operating state diagram 546
Figure 43 – Synchronized Network Change Processing 549
Figure 44 – NAM state machine 562
Type 3
Figure 45 – Logical Token Passing ring 616
Figure 46 – PhL(T2) data service 621
...