1、_ SAE Technical Standards Board Rules provide that: “This report is published by SAE to advance the state of technical and engineering sciences. The use of this report is entirely voluntary, and its applicability and suitability for any particular use, including any patent infringement arising there
2、from, is the sole responsibility of the user.” SAE reviews each technical report at least every five years at which time it may be reaffirmed, revised, or cancelled. SAE invites your written comments and suggestions. Copyright 2011 SAE International All rights reserved. No part of this publication m
3、ay be reproduced, stored in a retrieval system or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of SAE. TO PLACE A DOCUMENT ORDER: Tel: 877-606-7323 (inside USA and Canada) Tel: +1 724-776-4970 (outside U
4、SA) Fax: 724-776-0790 Email: CustomerServicesae.org SAE WEB ADDRESS: http:/www.sae.org SAE values your input. To provide feedbackon this Technical Report, please visit http:/www.sae.org/technical/standards/J2178/4_201104 SURFACE VEHICLE RECOMMENDED PRACTICE J2178-4 APR2011 Issued 1995-02 Stabilized
5、2011-04 Superseding J2178-4 JUL2004 Class B Data Communication Network Messages - Message Definitions for Three Byte Headers RATIONALE The technical report covers technology, products, or processes which are mature and not likely to change in the foreseeable future. STABILIZED NOTICE This document h
6、as been declared “Stabilized“ by the SAE Vehicle Architecture for Data Communications Standards Committee and will no longer be subjected to periodic reviews for currency. Users are responsible for verifying references and continued suitability of technical requirements. Newer technology may exist.
7、TABLE OF CONTENTS1. Scope . 32. References . 42.1 Related Publications. 42.1.1 SAE Publications 42.1.2 ANSI Publication. 43. Terms and Definitions. 44 Abbreviations and Acronyms 55. General Information 66. Functional Target Address Assignments (Primary ID) 77. Function Read Target Address Assignment
8、s . 108. Message Assignments . 108.1 Engine Torque 128.2 Engine Air Intake 128.3 Throttle . 1387.4 Air Conditioning Clutch. 138.5 Engine RPM . 138.6 Wheels . 148.7 Vehicle Speed. 148.8 Traction Control 148.9 Brakes 158.10 Steering/Steering Wheel 158.11 Transmission/Transaxle/PRNDL . 168.12 Engine Se
9、nsors - Other 168.13 Engine Coolant. 17Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE J2178-4 Stabilized APR2011 Page 2 of 36 8.14 Engine Oil .178.15 Engine Systems - Other188.16 Suspension .188
10、.17 Vehicle Speed Control 198.18 Charging System 198.19 Charging System 208.20 Electrical Energy Management.218.21 Odometer218.22 Fuel System218.23 Ignition Switch/Starter.228.24 Tell Tales .228.25 Climate Control (HVAC) 238.26 Window Wiper/Washer .238.27 Mirrors.248.28 Door Locks248.29 External Acc
11、ess 258.30 Seat Motion/Control 258.31 Windows .268.32 Steering Column .268.33 Seat Switches .278.34 Restraints278.35 Exterior Lamps Outage.288.36 Exterior Lamps298.37 Interior Lamps Outage 308.38 Interior Lamps.308.39 Tires318.40 Defrost 318.41 Displays 318.42 Exterior Environment 318.43 Interior En
12、vironment328.44 Time/Date .328.45 Vehicle Identification .338.46 Network Control 339. Extended Address Assignments.339.1 Brakes, Tires, and Wheels339.2 HVAC Zones .349.3 Window Wiper/Washer, Defrost, and Photocell 349.4 Mirrors.349.5 Doors and Door Locks 349.6 Seats and Restraints.359.7 Windows .359
13、.8 External Lamps.359.9 Internal Lamps 36Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE J2178-4 Stabilized APR2011 Page 3 of 36 1. ScopeThis SAE Recommended Practice defines the information cont
14、ained in the header and data fields ofnon-diagnostic messages for automotive serial communications based on SAE J1850 Class B networks. Thisdocument describes and specifies the header fields, data fields, field sizes, scaling, representations, and datapositions used within messages.The general struc
15、ture of a SAE J1850 message frame without in-frame response is shown in Figure 1. Thestructure of a SAE J1850 message with in-frame response is shown in Figure 2. Figures 1 and 2 also show thescope of frame fields defined by this document for non-diagnostic messages. Refer to SAE J1979 forspecificat
16、ions of emissions related diagnostic message header and data fields. Refer to SAE J2190 for thedefinition of other diagnostic data fields. The description of the network interface hardware, basic protocoldefinition, the electrical specifications, and the CRC byte are given in SAE J1850.FIGURE 1SCOPE
17、 OF SAE J2178 FOR A SAE J1850 FRAME WITHOUT IN-FRAME RESPONSE (IFR)FIGURE 2SCOPE OF SAE J2178 FOR A SAE J1850 FRAME WITH IN-FRAME RESPONSE (IFR)SAE J1850 defines two and only two formats of message headers. They are the Single Byte header formatand the Consolidated header format. The Consolidated he
18、ader format has two forms, a Single Byte form anda three byte form. This document covers all of these formats and forms to identify the contents of messageswhich could be sent on a SAE J1850 network.This document consists of four parts, each published separately.SAE J2178-1 (Titled: Detailed Header
19、Formats and Physical Address Assignments) describes the two allowedforms of message header formats, single byte and consolidated. It also contains the physical node addressrange assignments for the typical sub-systems of an automobile.SAE J2178-2 (Titled: Data Parameter Definitions) defines the stan
20、dard parametric data which may beexchanged on SAE J1850 (Class B) networks. The parameter scaling, ranges, and transfer functions arespecified. Messages that refer to these parametric definitions shall always adhere to these parametricdefinitions. It is intended that at least one of the definitions
21、for each parameter in this part match the SAEJ1979 definition.SAE J2178-3 (Titled: Frame IDs for Single Byte Forms of Headers) defines the message assignments for thesingle byte header format and the one byte form of the consolidated header format.SAE J2178-4 (this part, Titled: Message Definition f
22、or Three Byte Headers) defines the message assignmentsfor the three byte form of the consolidated header format.Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE J2178-4 Stabilized APR2011 Page 4 o
23、f 36 2. References2.1 Related PublicationsThe following publications are provided for information purposes only and are not arequired part of this document.2.1.1 SAE PUBLICATIONSAvailable from SAE, 400 Commonwealth Drive, Warrendale, PA 15096-0001.SAE J1213/1Glossary of Vehicle Networks for Multiple
24、x and Data CommunicationSAE J1850Class B Data Communication Network InterfaceSAE J1930Electrical/Electronic Systems Diagnostic Terms, Definitions, Abbreviations, and AcronymsSAE J1979E/E Diagnostic Test ModesSAE J2190Enhanced E/E Diagnostic Test Modes2.1.2 ANSI PUBLICATIONAvailable from ANSI, 25 Wes
25、t 43rd Street, New York, NY 10036-8002.ANSI/IEEE Std 754-1985, August 12, 1985IEEE Standard for Binary Floating-Point Arithmetic3. Terms and Definitions3.1 Data Data FieldData and data field are used interchangeably in this document and they both refer to a fieldwithin a frame that may include bytes
26、 with parameters pertaining to the message and/or secondary ID and/orextended addresses and/or test modes which further defines a particular message content being exchangedover the network.3.2 Extended AddressThe extended address is a means to allow a message to be addressed to a specificgeographica
27、l location or zone of the vehicle, independent of any nodes physical address.3.3 FrameA frame is one complete transmission of information which may or may not include an In-FrameResponse. The frame is enclosed by the start of frame and end of frame symbols. For Class B networks, eachframe contains o
28、ne and only one message (see “message“ definition below).3.4 Frame IDThe Frame ID is the header byte for the Single Byte Header format and the one byte form of theConsolidated header format. The definition of the frame ID is found in SAE J2178/3. This header byte definesthe target and source and con
29、tent of the frame.3.5 Functional AddressingFunctional addressing allows a message to be addressed or sent to one or morenodes on the network interested in that function. Functional addressing is intended for messages that may beof interest to more than a single node. For example, an exterior lamp “o
30、ff“ message could be sent to all nodescontrolling the vehicle exterior lamps by using a functional address. The functional address consists of aprimary ID and may include a secondary ID and may also include an extended address.3.6 Header Header FieldThe header (or header field, used interchangeably)
31、 is a one or three byte field withina frame that contains information about the message priority, message source and target addressing, messagetype, and in-frame response type.3.7 In-Frame Response (IFR) TypeThe IFR type identifies the form of the in-frame response which is expectedwithin that messa
32、ge.3.8 LoadThe load command indicates the operation of directly replacing the current/existing value of aparameter with the parameter value(s) contained in the message.3.9 MessageA message consists of all of the bytes of a frame excluding the delimiter symbols (SOF, EOD, EOF,NB).Copyright SAE Intern
33、ational Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE J2178-4 Stabilized APR2011 Page 5 of 36 3.10 ModifyThe modify command indicates the operation of using the message data parameter value to change(e.g., increment, decr
34、ement, or toggle) the current/existing value.3.11 ParameterA parameter is the variable quantity included in some messages. The parameter value, scaling,offset, units, transfer function, etc., are unique to each particular message. (The assigned parameters arecontained herein.)3.12 Physical Addressin
35、gPhysical addressing allows a message to be addressed to a specific node or to allnodes or to a non-existent, null node. The information in this message is of relevance only to a particular node,so the other nodes on the bus should ignore the message, except for the case of the “all nodes“ address.3
36、.13 Primary IDThe primary ID identifies the target for this functional message. This is the primary discriminatorused to group functions into main categories.3.14 PriorityThe priority describes the rank order and precedence of a message. Based upon the SAE J1850,Class B arbitration process, the mess
37、age with the highest priority will win arbitration.3.15 ReportA report indicates the transmission of parametric data values, based on: a change of state; a changeof value; on a periodic rate basis; or as a response to a specific request.3.16 RequestA request is a command to, or a query for data, or
38、action from another node on the network.3.17 Response DataThe response data is the information from a node on the network in response to a requestfrom another node on the network. This may be an in-frame response or a report type of message.3.18 Secondary IDThe secondary ID (along with the primary I
39、D or Frame ID) identifies the functional target nodefor a message. The purpose of the secondary ID field within the frame is to further define the function or actionbeing identified by the primary ID.4. Abbreviations and AcronymsA/C - Air ConditioningASC - ASCII Encoded SLOTBCD - Binary Coded Decima
40、l (BCD) SLOTBMM - Bit Mapped with Mask SLOTBMP - Bit Mapped without Mask SLOTCRC - Cyclic Redundancy CheckCS - ChecksumDTC - Diagnostic Trouble CodeEOD - End of DataEOF - End of FrameERR - Error DetectionEV-ETS - Electric Vehicle Energy Transfer SystemEVSE - Electric Vehicle Supply EquipmentHVAC - H
41、eating, Ventilation, Air ConditioningID - IdentifierIFR - In-Frame ResponseLSB - Least Significant Bit/ByteMSB - Most Significant Bit/ByteNB - Normalization BitPID - Parameter IDentification (number, NOT the primary ID, (see Section 7)PKT - Multiple Parameter Packet SLOTPRN - Parameter Reference Num
42、berSED - State Encoded SLOTCopyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE J2178-4 Stabilized APR2011 Page 6 of 36 SFP - Signed Floating Point (Scientific Notation) SLOTSLOT - Scaling, Limit, Off
43、set, and Transfer Function (see Section 8)SNM - 2s Complement Signed Numeric SLOTSOF - Start of FrameUNM - Unsigned Numeric SLOTVIN - Vehicle Identification Number5. General InformationThe messages defined by this four part document are specified for networks using onebyte headers or consolidated on
44、e and three byte headers as specified in SAE J1850. This part focuses on themessage definition for the three byte form of the consolidated header format. Section 5 consists of the list offunctional target addresses for all of the functionally addressed SAE J1850 messages except Type #3,Function Read
45、. The SAE J1850 Type #3 messages have a separate address assignment because thismessage type does not support any secondary addressing. Functional target addresses (Primary IDs) areshown in Section 5 and secondary message definitions are shown in Section 7. Section 6 shows the validextended address
46、assignments which are referenced in the message definition tables.The information in the header field contains target, source, priority and message type information, while thedata field contains additional addressing and parametric information. This information is explicitly defined insome headers a
47、nd implicitly defined in others. Messages can be classified generally into two types:a. Requests, that is, commands (load or modify) or queries for data, andb. Responses, that is, reports or acknowledgments.When a node generates a request, the target node(s) which is/are responsible for the requeste
48、d data orfunction must respond by sending the requested information or by performing the requested function. Forresponses (that is, reports or acknowledgments), data information that a node responds with may be requestedby another node, or reported by the node when the desired information has changed, or reported by the nodeon a periodic basis.This document defines a great number of specific messages which are expected to have wide application.Designers are required to use the defined messages on SAE J1850 networks in the exact way that they aredefined here. T
