ISO 11898-1:2015

Road vehicles — Controller area network (CAN) — Part 1: Data link layer and physical signalling

ISO 11898-1:2015 specifies the characteristics of setting up an interchange of digital information between modules implementing the CAN data link layer. Controller area network is a serial communication protocol, which supports distributed real-time control and multiplexing for use within road vehicles and other control applications. ISO 11898-1:2015 specifies the Classical CAN frame format and the newly introduced CAN Flexible Data Rate Frame format. The Classical CAN frame format allows bit rates up to 1 Mbit/s and payloads up to 8 byte per frame. The Flexible Data Rate frame format allows bit rates higher than 1 Mbit/s and payloads longer than 8 byte per frame. ISO 11898-1:2015 describes the general architecture of CAN in terms of hierarchical layers according to the ISO reference model for open systems interconnection (OSI) according to ISO/IEC 7498‑1. The CAN data link layer is specified according to ISO/IEC 8802‑2 and ISO/IEC 8802‑3. ISO 11898-1:2015 contains detailed specifications of the following: logical link control sub-layer; medium access control sub-layer; and physical coding sub-layer. There are three implementation options. They are the following: support of the Classical CAN frame format only, not tolerating the Flexible Data Rate frame format; support of the Classical CAN frame format and tolerating the Flexible Data Rate frame format; and support of the Classical CAN frame format and the Flexible Data Rate frame format. The last option is recommended to be implemented for new designs.

Véhicules routiers — Gestionnaire de réseau de communication (CAN) — Partie 1: Couche liaison de données et signalisation physique

General Information

• Status: Published
• Publication Date: 13-Dec-2015
• ICS: 43.040.15 - Car informatics. On board computer systems
• Technical Committee: ISO/TC 22/SC 31 - Data communication
• Drafting Committee: ISO/TC 22/SC 31/WG 3 - In-vehicle networks
• Current Stage: 9092 - International Standard to be revised
• Completion Date: 28-Jun-2021

Relations

• Revises: ISO 11898-1:2003 - Road vehicles — Controller area network (CAN) — Part 1: Data link layer and physical signalling
• Effective Date: 02-Mar-2013

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 11898-1
Second edition
2015-12-15
Road vehicles — Controller area
network (CAN) —
Part 1:
Data link layer and physical signalling
Véhicules routiers — Gestionnaire de réseau de communication
(CAN) —
Partie 1: Couche liaison de données et signalisation physique
Reference number
ISO 11898-1:2015(E)
©
ISO 2015

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ISO 11898-1:2015(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO 2015, Published in Switzerland
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form
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ISO 11898-1:2015(E)

Contents Page
Foreword .vi
Introduction .vii
1 Scope . 1
2 Conformance . 1
3 Normative references . 2
4 Terms and definitions . 2
5 Symbols and abbreviated terms . 5
6 Basic concepts of CAN . 7
6.1 CAN properties . 7
6.2 Frames . 8
6.3 Bus access method . 8
6.4 Information routing . 8
6.5 Network flexibility . 8
6.6 Data consistency . 8
6.7 Remote data request . 8
6.8 Error detection . 9
6.9 Error signalling and recovery time . 9
6.10 ACK . 9
6.11 Automatic retransmission . 9
6.12 Fault confinement. 9
6.13 Error-active . 9
6.14 Error-passive . 9
6.15 Bus-off .10
7 Layered architecture of CAN .10
7.1 Reference to OSI model .10
7.2 Protocol specification .11
7.3 Format description of services .11
7.3.1 Format description of service primitives .11
7.3.2 Types of service primitives .12
7.4 LLC interface .12
8 Description of LLC sub-layer .12
8.1 General .12
8.2 Services of LLC sub-layer .13
8.2.1 Types of connectionless-mode transmission services .13
8.2.2 Service primitive specification .13
8.3 Functions of LLC sub-layer .18
8.3.1 General.18
8.3.2 Frame acceptance filtering .18
8.3.3 Overload notification .18
8.3.4 Recovery management .19
8.4 Structure of LLC frames .19
8.4.1 General.19
8.4.2 Specification of LLC DF .19
8.4.3 Specification of LLC RF .20
8.5 Limited LLC frames .21
9 Interface between LLC and MAC .21
9.1 Services .21
9.2 Time and time triggering .21
9.2.1 Description . . .21
9.2.2 Time base .21
9.2.3 Time reference point .21
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ISO 11898-1:2015(E)

9.2.4 Event generation .22
9.3 Disabling automatic retransmission .22
9.3.1 Retransmission of frames.22
9.4 Message time stamping .22
10 Description of MAC sub-layer .22
10.1 General .22
10.2 Services of MAC sub-layer .22
10.2.1 Service description .22
10.2.2 Service primitives specification .23
10.3 Functional model of MAC sub-layer architecture .27
10.3.1 Capability .27
10.3.2 Frame transmission . .27
10.3.3 Frame reception .28
10.4 Structure of MAC frames.29
10.4.1 Description . . .29
10.4.2 Specification of MAC DF .29
10.4.3 Specification of MAC RF .34
10.4.4 Specification of EF .34
10.4.5 Specification of OF .35
10.4.6 Specification of inter-frame space .36
10.5 Frame coding .37
10.6 Frame acknowledgement .37
10.7 Frame validation .37
10.8 Order of bit transmission .38
10.9 Medium access method .39
10.9.1 General.39
10.9.2 Multi-master .39
10.9.3 Bus access .40
10.9.4 Bus integration state .40
10.9.5 Protocol exception event.40
10.9.6 Transmission of MAC frames .40
10.9.7 Content-based arbitration .40
10.9.8 Frame priority .41
10.9.9 Collision resolution .41
10.9.10 Disabling of frame formats .41
10.10 MAC data consistency .41
10.11 Error detection .41
10.12 Error signalling .42
10.13 Overload signalling .43
10.14 Bus monitoring .44
10.15 Restricted operation . .44
11 PL specification .44
11.1 General and functional modelling .44
11.2 Services of PL .44
11.2.1 Description . . .44
11.2.2 PCS_Data.Request .45
11.2.3 PCS_Data.Indicate .45
11.2.4 PCS_Status.Transmitter .45
11.2.5 PCS_Status.Receiver.45
11.3 PCS specification.45
11.3.1 Bit encoding/decoding .45
11.3.2 Synchronization .50
11.3.3 Transmitter delay compensation.52
11.4 AUI specification .54
11.4.1 General.54
11.4.2 PCS to PMA messages .55
11.4.3 PMA to PCS message .55
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ISO 11898-1:2015(E)

12 Description of supervisor FCE .55
12.1 Fault confinement.55
12.1.1 Objectives .55
12.1.2 Strategies .55
12.1.3 Fault confinement interface specification .56
12.1.4 Rules of fault confinement .58
12.1.5 Network start-up .60
12.2 Bus failure management .60
Annex A (informative) Additional Information .61
Bibliography .65
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ISO 11898-1:2015(E)

Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation on the meaning of ISO specific terms and expressions related to conformity
assessment, as well as information about ISO’s adherence to the WTO principles in the Technical
Barriers to Trade (TBT), see the following URL: Foreword — Supplementary information.
The committee responsible for this document is ISO/TC 22, Road vehicles, Subcommittee SC 31, Data
communication.
This second edition cancels and replaces the first edition (ISO 11898-1:2003), which has been technically
revised. It also incorporates the Corrigendum ISO 11898-1:2003/Cor 1:2006.
ISO 11898 consists of the following parts, under the general title Road vehicles — Controller area
network (CAN):
— Part 1: Data link layer and physical signalling
1)
— Part 2: High-speed medium access unit
— Part 3: Low-speed, fault-tolerant, medium-dependent interface
— Part 4: Time-triggered communication
1)
— Part 5: High-speed medium access unit with low-power mode
1)
— Part 6: High-speed medium access unit with selective wake-up functionality
1) Parts 2, 5, and 6 are being revised. They will be merged under a new edition of Part 2.
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ISO 11898-1:2015(E)

Introduction
ISO 11898 was first published as one document in 1993. It covered the CAN data link layer, as well as
the high-speed physical layer.
In the reviewed and restructured ISO 11898 series:
— Part 1 defines the data link layer including the logical link control (LLC) sub-layer and the medium
access control (MAC) sub-layer, as well as the physical signalling (PHS) sub-layer;
— Part 2 defines the high-speed physical medium attachment (PMA);
— Part 3 defines the low-speed fault-tolerant physical medium attachment (PMA);
— Part 4 defines the time-triggered communication;
— Part 5 defines the power modes of the high-speed physical medium attachment (PMA);
— Part 6 defines the selective wake-up functionality of the high-speed physical medium attachment
(PMA).
NOTE ISO 11898-2 is updated in parallel to the update of this part of ISO 11898 to combine the functions
described in ISO 11898-2, ISO 11898-5 and ISO 11898-6. (The future edition of ISO 11898-2 will cancel and
replace the current ISO 11898-2:2003, ISO 11898-5:2007 and ISO 11898-6:2013)
Figure 1 shows the relations between the OSI reference layers and the parts of the ISO 11898 series.
NOTE ISO 11898-2 refers to the future edition that will cancel and replace the current ISO 11898-2:2003,
ISO 11898-5:2007 and ISO 11898-6:2013.
Figure 1 — CAN data link and physical sub-layers relation to the OSI model
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INTERNATIONAL STANDARD ISO 11898-1:2015(E)
Road vehicles — Controller area network (CAN) —
Part 1:
Data link layer and physical signalling
1 Scope
This part of ISO 11898 specifies the characteristics of setting up an interchange of digital information
between modules implementing the CAN data link layer. Controller area network is a serial
communication protocol, which supports distributed real-time control and multiplexing for use within
road vehicles and other control applications.
This part of ISO 11898 specifies the Classical CAN frame format and the newly introduced CAN Flexible
Data Rate Frame format. The Classical CAN frame format allows bit rates up to 1 Mbit/s and payloads
up to 8 byte per frame. The Flexible Data Rate frame format allows bit rates higher than 1 Mbit/s and
payloads longer than 8 byte per frame.
This part of ISO 11898 describes the general architecture of CAN in terms of hierarchical layers
according to the ISO reference model for open systems interconnection (OSI) according to ISO/IEC 7498-
1. The CAN data link layer is specified according to ISO/IEC 8802-2 and ISO/IEC 8802-3.
This part of ISO 11898 contains detailed specifications of the following (see Figure 2):
— logical link control sub-layer;
— medium access control sub-layer;
— physical coding sub-layer.
There are three implementation options. They are the following:
— support of the Classical CAN frame format only, not tolerating the Flexible Data Rate frame format;
— support of the Classical CAN frame format and tolerating the Flexible Data Rate frame format;
— support of the Classical CAN frame format and the Flexible Data Rate frame format.
The last option is recommended to be implemented for new designs.
NOTE Implementations of the first option can communicate with implementations of the third option
...