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4、0 (outside USA) Fax: 724-776-0790 Email: CustomerServicesae.org SAE WEB ADDRESS: http:/www.sae.org SAE values your input. To provide feedback on this Technical Report, please visit http:/www.sae.org/technical/standards/J1939/2_201303 SURFACE VEHICLE RECOMMENDED PRACTICE J1939-2 MAR2013 Issued 2006-0
5、8 Revised 2013-03Superseding J1939-02 AUG2006 Agricultural and Forestry Off-Road Machinery Control and Communication Network RATIONALE Updates have been made to synchronize this document with updates in other documents of the series. Language has been clarified. A section on how to design ECUs for b
6、oth Truck & Bus and Agricultural & Forestry networks has been added. A section documenting the process used to standardize A&F networks has been added. FOREWORD The SAE J1939 communications network is defined using a collection of individual SAE J1939 documents based upon the layers of the Open Syst
7、em Interconnect (OSI) model for computer communications architecture. The SAE J1939-02 document specifies a particular set of SAE J1939 documents which define an SAE J1939 network as it applies to agricultural and forestry equipment. The SAE J1939 communications network is a high speed ISO 11898-1 C
8、AN based communications network that supports real-time closed loop control functions, simple information exchanges, and diagnostic data exchanges between Electronic Control Units (ECUs) physically distributed throughout the vehicle. The SAE J1939 communications network is developed for use in heavy
9、-duty environments and suitable for horizontally integrated vehicle industries. The SAE J1939 communications network is applicable for light-duty, medium-duty, and heavy-duty vehicles used on-road or off-road, and for appropriate stationary applications which use vehicle derived components (e.g., ge
10、nerator sets). Vehicles of interest include, but are not limited to, on-highway and off-highway trucks and their trailers, construction equipment, and agricultural equipment and implements. The physical layer aspects of SAE J1939 reflect its design goal for use in heavy-duty environments. Horizontal
11、ly integrated vehicles involve the integration of different combinations of loose package components, such as engines and transmissions that are sourced from many different component suppliers. The SAE J1939 common communication architecture strives to offer an open interconnect system that allows t
12、he ECUs associated with different component manufacturers to communicate with each other. SAE J1939-2 Revised MAR2013 Page 2 of 15 TABLE OF CONTENTS 1. SCOPE 2 2. REFERENCES 3 2.1 Related Publications . 3 2.1.1 ISO Publications 3 2.1.2 NMEA Publications . 3 3. DEFINITIONS . 3 3.2 Abbreviations 5 4.
13、DOCUMENTATION STRUCTURE . 5 5. STANDARDIZATION PROCESS WITH REGARD TO AG AND FORESTRY NETWORKS . 7 5.1 Communication and Administration 7 5.2 Messages 7 5.3 Parameters 8 5.4 Additional items . 8 6. TECHNICAL REQUIREMENTS 8 6.1 Network Description 8 6.2 Physical Layer . 9 6.3 Data Link Layer . 10 6.4
14、 Network Layer . 10 6.5 Application Layers . 11 6.6 Network Management . 11 6.7 Virtual Terminal . 12 6.8 Tractor ECU 13 6.9 Task Controller 13 6.10 Management Computer Interface . 13 7. DESIGNING A&F NETWORKS 14 7.1 Network interface 14 7.2 Low level CAN drivers . 15 7.3 High level protocol items .
15、 15 8. NOTES 15 8.1 Marginal Indicia . 15 1. SCOPE SAE J1939-02 Agricultural and Forestry Off-Road Machinery Network specifies the requirements for application of SAE J1939 in agricultural and forestry equipment. This document specifies the series of documents within the set of SAE J1939 documents t
16、hat are applicable to agricultural and forestry equipment and provides further requirements for this industry. The SAE and ISO groups have cooperated to define agricultural and forestry networks in a manner to allow compatibility of ECUs and messaging protocols between the A&F and the T&B networks.
17、SAE J1939-2 Revised MAR2013 Page 3 of 15 2. REFERENCES 2.1 Related Publications The following publications are provided for information purposes only and are not a required part of this SAE Technical Report. 2.1.1 ISO Publications Available from American National Standards Institute, 25 West 43rd St
18、reet, New York, NY 10036-8002, Tel: 212-642-4900, www.ansi.org. ISO 11783 Tractors and Machinery for Agriculture and Forestry - Serial Control and Communications Data Network 2.1.2 NMEA Publications Available from National Marine Electronics Association, 7 Riggs Ave., Severna Park, MD 21146, 410-975
19、-9425, www.nmea.org. NMEA 2000 National Marine Electronics Association Standard for Serial-Data Networking of Marine Electronic Devices 3. DEFINITIONS Terms and abbreviations are defined in SAE J1939 Top Level for use in the context of this document. Additional terms are defined below. 3.1 TERMS 3.1
20、.1 Controller Application The software within an Electronic Control Unit (ECU) that performs a particular control function. More than one Controller Application may reside within an ECU. 3.1.2 Configurable Messages A set of message PGNs that can be configured to contain any desired combination of a
21、set of parameters (SPNs) that are designated to be configurable. 3.1.3 Farm Management Information System The office computer system for the farmer or contractor. It includes the software for farm management such as book keeping, payroll, resource management for machines, products, workers, field ma
22、nagement, GIS, decision support systems and task management. 3.1.4 Fast Packet A transport protocol method employing broadcast messages with no minimum separation between packets 3.1.5 Implement Network Network segment that connects agricultural implement ECUs as well as some tractor ECUs such as Vi
23、rtual Terminal SAE J1939-2 Revised MAR2013 Page 4 of 15 3.1.6 ISOBUS Standardization of the agricultural implement network defined in ISO 11783 3.1.7 Management Computer Interface The method of exchanging information between the FMIS and the vehicle Task Controllers using XML data format. A physical
24、 interface is not specified. 3.1.8 Network Interconnection ECU A device that exists primarily for interconnecting networks or sub networks. Specific implementations for “forwarding” messages include: Repeater, Bridge, Router, and Gateway. 3.1.9 Process Data A message that is used for the transmissio
25、n of measured data and/or set point commands to one or more controllers. 3.1.10 Task Controller An electronic unit on the mobile implement control system that is responsible for the sending, receiving and logging of Process Data. A Task Controller may have an operator interface. 3.1.11 Termination B
26、ias Circuit A circuit required at each end of a network segment that provides bias voltages for the CAN High and CAN Low signals and the common mode impedance termination for the respective conductors. 3.1.12 Tractor Network Network segment that connects mainly tractor mounted ECUs including power t
27、rain modules. 3.1.13 Tractor ECU Standardized network interconnect device between tractor network and implement network. 3.1.14 Virtual Terminal An ECU, consisting of a graphical display and input functions, which provides the capability to display information to and retrieve data from an operator f
28、or a connected implement or Working Set. SAE J1939-2 Revised MAR2013 Page 5 of 15 3.2 ABBREVIATIONS Abbreviations are defined in SAE J1939 for use in the context of this document. A&F Agricultural and Forestry - A&F networks are those that are governed by this document and by ISO 11783 CA Controller
29、 Application ECU Electronic Control Unit. Any of a number of electronic modules contained in a machine that communicates with other ECUs via the SAE J1939 network standard. ETP Extended Transport Protocol FMIS Farm Management Information System ISO International Organization for Standardization ISO/
30、TC 23/SC 19/WG 1 International Organization for Standards, Technical Committee 23, subcommittee 19, working group 1- the group responsible for maintaining the ISOBUS protocol standard for A&F networks NMEA National Marine Electronics Association SAE Society of Automotive Engineers SPN Suspect Parame
31、ter Number T&B Truck and Bus TBC Termination Bias Circuit VT Virtual Terminal XML eXtensible Markup Language 4. DOCUMENTATION STRUCTURE General information regarding this series of recommended practices is found in SAE J1939. Agricultural and forestry CAN communication networks are defined and stand
32、ardized based upon the SAE J1939 T&B standard and further elaborated in ISO 11783 to produce compatible networks. See section 5 for details of the working process between SAE and ISO working groups. A subset of the SAE J1939 documents is applicable for forestry and agricultural equipment. A combinat
33、ion of the SAE J1939 and ISO 11783 documents completely specifies the agricultural and forestry off-road control and communications networks. The series of documents applicable for agricultural and forestry equipment are listed in Table 1. Some information relating to foundation principles on which
34、the networks operate are contained in both sets of documents. Other information relating to A&F application specific features and services are contained only in the ISO documents. Section 6 of this document summarizes the major points about each of the documents listed above. Additionally, section 7
35、 gives some guidance for those familiar with SAE J1939 who may want to design ECUs that will also be compatible with the Ag and Forestry networks described here. SAE J1939-2 Revised MAR2013 Page 6 of 15 TABLE 1 - A&F APPLICABLE DOCUMENTS SAE Document ISO Document Summary SAE J1939 Top Level Document
36、 N/A This top-level document describes the network in general and its appendices include pre-assigned NAMES, preferred addresses, PGNs and suspect parameters. SAE J1939-02 Agricultural and Forestry Off Road Machinery Control and Communication Network ISO 11783 Part 1 General Standard The application
37、 layer for off-road equipment being described in this document. A primary intent of this document is to describe the A&F network and the harmonization of SAE and ISO standards that results in a complete network definition. This standard specifies a serial data network for control and communications
38、on forestry or agricultural tractors, mounted, semi-mounted, towed or self-propelled implements. Its purpose is to standardize the method and format of transfer of data between sensors, actuators, control elements, information storage and display units whether mounted on or part of the tractor, or a
39、ny implements. No SAE equivalent. See ISO Document ISO 11783 Part 2 Physical Layer The agricultural implement network physical layer consists of a 250 K bit/s, twisted, non-shielded, quad-cable physical layer and active terminators. This physical layer is unique to A & F. ECUs designed for the T &B
40、networks are compatible with this physical layer. SAE J1939-13 Diagnostics Connector Included in ISO 11783 Part 2 The Off-Board Diagnostic connector used on the vehicle to get access to the vehicle communication links. A & F networks use the type 1 connector for 250K baud. SAE J1939-14 Physical Laye
41、r, 500Kbps No ISO equivalent. See SAE Document. 500k baud currently not used in A & F networks SAE J1939-21 Data Link Layer ISO 11783 Part 3 Data Link Layer These documents describe the use of the CAN 29 bit identifier and the basic transport protocol mechanism. SAE J1939-31 Network Layer ISO 11783
42、Part 4 Network Layer These documents describe the network layer, which defines the requirements and services needed for communication between electronic control units in different segments of the off-road network. The various types of network interconnection unit are defined. The ISO document includ
43、es a powerful capability allowing connections to be established between networks with separate address spaces. SAE J1939-71 Application Layer ISO 11783 Part 8 Powertrain Messages These particular standards contain the Messages required by tractors and self-propelled implements on the powertrain or t
44、ractor network. No SAE equivalent. See ISO Document ISO 11783 Part 7 Implement Messages Application Layer for Agriculture This part of ISO 11783 describes the tractor-implement specific messages application layer of the network, specifying the message set and defining the messages used for communica
45、tion with and between tractors and connected implements. No SAE equivalent. See ISO Document IISO 11783 Part 6 Virtual Terminal This part of ISO 11783 describes a universal Virtual Terminal that can be used by an operator to interface with both tractor and implement electronic control units. SAE J19
46、39-73 Diagnostics Application IISO 11783 Part 12 The diagnostics application layer. No SAE equivalent. See ISO Document ISO 11783 Part 9 Tractor ECU This part of ISO 11783 describes the tractor ECU, the electronic control unit that provides the gateway between the networks tractor and implement netw
47、orks, as well as performing other tractor functions. No SAE equivalent. See ISO Document ISO 11783 Part 10 Task Controller This particular standard describes the Task Controller Applications Layer, which defines the requirements and services needed for communicating between a task controller in the
48、system and electronic control units of one or more implements. The data format to communicate with the farm management computer, the calculations required for control and the message format sent to the ECU are defined in this document. No SAE equivalent. See ISO Document ISO 11783 Part 11 Mobile Dat
49、a Element Dictionary This particular standard describes the Data Elements that are used by the Process Data Messages as defined in Part 10 of this standard. This data dictionary information is available as an online data base. No SAE equivalent. See ISO Document ISO 11783 Part 13 File Server This particular document section describes a File Server capability for use by tractors and self-propelled implements for storage of large amounts of d
