没有合适的资源?快使用搜索试试~ 我知道了~
首页SAE J2716_201001 (SENT协议).pdf
资源详情
资源评论
资源推荐

__________________________________________________________________________________________________________________________________________
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 therefrom, 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 © 2010 SAE International
All rights reserved. No part of this publication may 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: 724-776-4970 (outside USA)
Fax: 724-776-0790
Email: CustomerService@sae.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/J2716_201001
SURFACE
VEHICLE
INFORMATION
REPORT
J2716 JAN2010
Issued 2007-04
Revised 2010-01
Superseding J2716 FEB2008
(R) SENT—Single Edge Nibble Transmission for Automotive Applications
RATIONALE
Revised based on feedback from suppliers making production versions.
1. Changes meet the new EMC standard IEC 62132-4.
2. Addition of an optional pause pulse
3. Defining a new enhanced serial message as an optional replacement for the original short serial data message
4. Clarifying the diagnostics and remedial actions for successive calibration pulses comparisons
5. Added recommended modification to 4-bit checksum calculation. Recommended checksum calculation includes
processing a zero nibble in addition to the data nibbles to protect for common error in last data nibble and checksum.
The original CRC method is retained as an option for designs already in process or production that were developed
according to previous SENT norms.
6. Added new recommended circuit topology to better handle 3.3V systems. All new sensors should use the
recommended topology. The original topology is retained as an option for designs already in process or production
that were developed according to previous SENT norms.
7. Added configuration shorthand notation
8. Updated MAF, Temperature and Pressure applications to take advantage of the new Enhanced Serial Message
9. Added EMC Susceptibility testing guidelines
10. Added reset action by transmitter
11. Changes for clarifications or to address typos.
THIS DOCUMENT IS PROTECTED BY U.S. AND INTERNATIONAL COPYRIGHT LAWS.
It may not be reproduced, stored in a retrieval system, distributed or transmitted, in whole or in part, in any form or by any means.
Copyright 2013. Downloaded from SAE International by Walter Goelles, Tuesday, February 19, 2013 06:55:17 AM

SAE J2716 Revised JAN2010 Page 2 of 56
TABLE OF CONTENTS
1.
SCOPE .......................................................................................................................................................... 4
1.1 Overview ....................................................................................................................................................... 4
2. REFERENCES .............................................................................................................................................. 4
2.1 Applicable Publications ................................................................................................................................. 4
2.1.1 SAE Publications ........................................................................................................................................... 4
2.1.2 ISO Publications ............................................................................................................................................ 4
2.1.3 Supplier Publications .................................................................................................................................... 4
2.1.4 Other Publications ......................................................................................................................................... 5
3. DEFINITION OF TERMS .............................................................................................................................. 5
3.1 Glossary ........................................................................................................................................................ 5
3.1.1 Media ............................................................................................................................................................ 5
3.1.2 Protocol ......................................................................................................................................................... 5
3.1.3 Message ........................................................................................................................................................ 5
3.1.4 Radiated Emissions ...................................................................................................................................... 5
3.1.5 Radiated Immunity ........................................................................................................................................ 5
3.1.6 Receiver Module ........................................................................................................................................... 5
3.1.7 Transmitter Module ....................................................................................................................................... 5
3.1.8 Nominal ......................................................................................................................................................... 5
3.1.9 Pulse Period .................................................................................................................................................. 5
3.1.10 Error .............................................................................................................................................................. 6
3.1.11 Fault .............................................................................................................................................................. 6
4. ACRONYMS, ABBREVIATIONS, AND SYMBOLS ...................................................................................... 6
5. SENT SYSTEM REQUIREMENTS ............................................................................................................... 6
5.1 General Requirements .................................................................................................................................. 6
5.2 Message Definitions ...................................................................................................................................... 7
5.2.1 Transmission Sequence ............................................................................................................................... 7
5.2.2 Transmission Properties of Calibration/Synchronization Pulse .................................................................... 7
5.2.3 Transmission Properties of Nibble Pulse ...................................................................................................... 7
5.2.4 Status and Communication Nibble ............................................................................................................... 8
5.2.5 Checksum Nibble ........................................................................................................................................ 12
5.2.6 Pause Pulse (Optional) ............................................................................................................................... 12
5.3 Transmission and Reception of Message ................................................................................................... 13
5.3.1 Transmission of Message ........................................................................................................................... 13
5.3.2 Adjustment of Received Message Nibble Lengths ..................................................................................... 13
5.3.3 Received Message Diagnostics .................................................................................................................. 13
5.3.4 Reset ........................................................................................................................................................... 15
5.4 Checksum Nibble Details ............................................................................................................................ 15
5.4.1 Errors Detected and Not Detected by Checksum ....................................................................................... 15
5.4.2 CRC Implementation ................................................................................................................................... 18
6. SENT PHYSICAL LAYER OPERATION..................................................................................................... 19
6.1 Normal Communication Mode and Transmission Rate .............................................................................. 19
6.2 Clock Tolerance .......................................................................................................................................... 20
6.2.1 Transmitter–Receiver Communications ...................................................................................................... 20
6.3 Electrical Interface Requirements ............................................................................................................... 21
6.3.1 Transmitter Driver Requirements ................................................................................................................ 23
6.3.2 Receiver Input Requirements ..................................................................................................................... 25
6.3.3 Bus Wiring Harness and ECU Connectors ................................................................................................. 26
6.4 ESD Immunity ............................................................................................................................................. 26
6.5 EMC Testing Requirements ........................................................................................................................ 26
6.6 Fault Protection Modes ............................................................................................................................... 26
7. CONFIGURATION SHORTHAND .............................................................................................................. 26
7.1 Shorthand Definition ................................................................................................................................... 26
8. NOTES ........................................................................................................................................................ 27
8.1 Marginal Indicia ........................................................................................................................................... 27
THIS DOCUMENT IS PROTECTED BY U.S. AND INTERNATIONAL COPYRIGHT LAWS.
It may not be reproduced, stored in a retrieval system, distributed or transmitted, in whole or in part, in any form or by any means.
Copyright 2013. Downloaded from SAE International by Walter Goelles, Tuesday, February 19, 2013 06:55:17 AM

SAE J2716 Revised JAN2010 Page 3 of 56
APPENDIX A RECOMMENDED APPLICATION SPECIFIC PROTOCOLS ..................................................................... 28
APPENDIX B CHECKSUM EXAMPLES ........................................................................................................................... 46
APPENDIX C EMC SUSCEPTIBILITY TESTING GUIDELINES ...................................................................................... 48
APPENDIX D SLOW CHANNEL MESSAGE IDS ............................................................................................................. 50
FIGURE 5.2.1-1 – EXAMPLE ENCODING SCHEME FOR TWO 12 BIT SIGNALS ......................................................... 7
FIGURE 5.2.3-1 – EXAMPLE NOMINAL NIBBLE TIMES .................................................................................................. 8
FIGURE 5.2.3-2 – CONTINUED EXAMPLE NIBBLE VALUES ......................................................................................... 8
FIGURE 5.2.4.1-1 - CONSTRUCTION OF SHORT SERIAL DATA MESSAGE FROM 16 SENT MESSAGES ................. 9
FIGURE 5.2.4.2-1 - CONSTRUCTION OF ENHANCED SERIAL DATA MESSAGE FROM 18 SENT MESSAGES ....... 10
FIGURE 5.2.4.2-2 - ENHANCED SERIAL MESSAGE FORMAT WITH 12-BIT DATA FIELD AND 8-BIT MESSAGE ID 10
FIGURE 5.2.4.2-3 - ENHANCED SERIAL MESSAGE FORMAT WITH 16-BIT DATA FIELD AND 4-BIT MESSAGE ID 11
FIGURE 5.2.4.3-1 - ORDER OF THE MESSAGE BITS, 24-BIT MESSAGE USED FOR CRC GENERATION ............... 11
FIGURE 5.3.3.1-1 - ERROR PATTERN FOR SUCCESSIVE CALIBRATION PULSE DETECTION. ............................... 14
FIGURE 5.3.3.1-2 - SUCCESSIVE CALIBRATION PULSE DETECTION. ........................................................................ 15
FIGURE 6.2.1-1 – CLOCK DRIFT ERROR AND JITTER REQUIREMENTS VERSUS NOMINAL CLOCK TICK ......... 21
FIGURE 6.3-1 – LEGACY SENT RECEIVER INTERFACE CIRCUIT TOPOLOGY ..................................................... 22
FIGURE 6.3-2 – RECOMMENDED SENT SYSTEM INTERFACE CIRCUIT TOPOLOGY .......................................... 22
FIGURE 6.3-3 – EXAMPLE LEGACY SENT SYSTEM INTERFACE CIRCUIT TOPOLOGY ...................................... 23
FIGURE 6.3-4 – EXAMPLE RECOMMENDED SENT SYSTEM INTERFACE CIRCUIT TOPOLOGY ........................ 23
FIGURE 6.3.1-1 – EXAMPLE SENT SHAPED WAVEFORM TRANSMITTER OUTPUT ............................................... 24
TABLE 5.2.4.1-1 - STATUS AND COMMUNICATION NIBBLE DESCRIPTION ............................................................... 8
TABLE 5.2.4.3-1 - UNDETECTED 3 AND 4 BIT ERRORS.............................................................................................. 12
TABLE 5.4.1-1 - BIT FLIP PATTERNS OVER TWO NIBBLES NOT DETECTABLE USING THE
CRC POLYNOMIAL ............................................................................................................................ 15
TABLE 5.4.1-2 - CHECKSUM MISSED DETECTION RATE, EDGE SHIFT BETWEEN TWO NIBBLES
(VALID FRAMES ONLY, RECOMMENDED IMPLEMENTATION) .................................................... 16
TABLE 5.4.1-3 - CHECKSUM MISSED DETECTION RATE, ASYMMETRICAL EDGE SHIFT OFFSET BY 1
BETWEEN TWO NIBBLES (VALID FRAMES ONLY, RECOMMENDED IMPLEMENTATION) ....... 17
TABLE 6.2.1-1 – COMMUNICATION CLOCK TOLERANCE ........................................................................................ 20
TABLE 6.3.1-1 – TRANSMITTER DRIVER REQUIREMENTS ..................................................................................... 24
TABLE 6.3.2-1 – RECEIVER INPUT REQUIREMENTS ................................................................................................ 25
TABLE 6.3.2-2 – RECEIVER POWER SUPPLY REQUIREMENTS ............................................................................. 25
TABLE 7.1-1 – SENT CONFIGURATION SHORTHAND DEFINITION ..................................................................... 27
THIS DOCUMENT IS PROTECTED BY U.S. AND INTERNATIONAL COPYRIGHT LAWS.
It may not be reproduced, stored in a retrieval system, distributed or transmitted, in whole or in part, in any form or by any means.
Copyright 2013. Downloaded from SAE International by Walter Goelles, Tuesday, February 19, 2013 06:55:17 AM

SAE J2716 Revised JAN2010 Page 4 of 56
1. SCOPE
This document defines a level of standardization in the implementation of the digital pulse scheme for reporting sensor
information via Single Edge Nibble Transmission (SENT) encoding. This standard will allow ECU and tool manufacturers
to satisfy the needs of multiple end users with minimum modifications to the basic design. This standard will benefit
vehicle Original Equipment Manufacturers (OEMs) by achieving lower ECU costs due to higher industry volumes of the
basic design.
Requirements stated in this document provide a minimum standard level of performance to which all compatible ECUs
and media shall be designed. This assures data communication among all connected devices regardless of supplier.
The intended audience includes, but is not limited to, ECU suppliers, sensor suppliers, component release engineers and
vehicle system engineers.
1.1 Overview
The Single Edge Nibble Transmission encoding scheme (SENT) is intended for use in applications where high resolution
sensor data needs to be communicated from a sensor to an Engine Control Unit (ECU). It is intended as a replacement
for the lower resolution methods of 10 bit A/D’s and PWM and as a simpler low cost alternative to CAN or LIN. The
implementation assumes that the sensor is a smart sensor containing a microprocessor or dedicated logic device (ASIC)
to create the signal.
SENT is a unidirectional communications scheme from sensor / transmitting device to controller /receiving device which
does not include a coordination signal from the controller/receiving device. The sensor signal is transmitted as a series of
pulses with data encoded as falling to falling edge periods. Details of the signal encoding may vary for specific sensor
applications described in various appendices of this specification.
2. REFERENCES
2.1 Applicable Publications
The following publications form a part of this specification to the extent specified herein. Unless otherwise indicated, the
latest version of SAE publications shall apply.
2.1.1 SAE Publications
Available from SAE, 400 Commonwealth Drive, Warrendale, PA 15096-0001, Tel: 877-606-7323 (inside USA and
Canada) or 724-776-4970 (outside USA), www.sae.org
.
SAE J551 (All parts) Performance Levels and Methods of Measurement of Electromagnetic Compatibility for Vehicles
and Devices
SAE J1113 (All parts) Electromagnetic Compatibility Measurement Procedures for Vehicle Components
SAE J1930 Electrical/Electronic Systems Diagnostic Terms, Definitions, Abbreviation and Acronyms
2.1.2 ISO Publications
Available from ANSI, 25 West 43rd Street, New York, NY 10036-8002, Tel: 212-642-4900, www.ansi.org
.
None.
2.1.3 Supplier Publications
None.
THIS DOCUMENT IS PROTECTED BY U.S. AND INTERNATIONAL COPYRIGHT LAWS.
It may not be reproduced, stored in a retrieval system, distributed or transmitted, in whole or in part, in any form or by any means.
Copyright 2013. Downloaded from SAE International by Walter Goelles, Tuesday, February 19, 2013 06:55:17 AM

SAE J2716 Revised JAN2010 Page 5 of 56
2.1.4 Other Publications
CISPR 25 Limits and Methods of Measurement of Radio Disturbance Characteristics for the Protection of
Receivers Used On Board Vehicles (available at webstore.iec.ch
).
ES-XW7T-1A278-AC Ford Component and Subsystem Electromagnetic Compatibility Worldwide Requirements and
Test Procedures (available at www.fordemc.com
. This document shall be referred to as the Ford
EMC Spec.)
GMW3097 General Specification for Electrical / Electronic Components and Subsystems, Electromagnetic
Compatibility (this document will be referred to as the GM EMC Spec.)
3. DEFINITION OF TERMS
3.1 Glossary
3.1.1 Media
The physical entity that conveys the electrical (or equivalent means of communication) signal transmission between
electronic devices.
3.1.2 Protocol
The formal set of conventions or rules for the exchange of information between electronic devices. This includes the
specification of the signal frame administration, frame transfer and physical layer.
3.1.3 Message
One sequence of calibration pulse and specified number of nibble pulses for that implementation. The number of nibbles
is constant for each implementation but the individual message times can vary depending on the specific values of the
nibbles.
3.1.4 Radiated Emissions
The energy that radiates from the physical layer.
3.1.5 Radiated Immunity
The level of susceptibility of physical layer components to communication errors in the presence of high energy
electromagnetic fields.
3.1.6 Receiver Module
The processor that receives the encoded signal. Generally an ECU with falling-edge detection and timing measurement
capabilities.
3.1.7 Transmitter Module
The device that generates the message to the receiver module. Generally a smart sensor.
3.1.8 Nominal
Time period assuming no transmitter clock error.
3.1.9 Pulse Period
Time between consecutive falling edges of the transmitting signal.
THIS DOCUMENT IS PROTECTED BY U.S. AND INTERNATIONAL COPYRIGHT LAWS.
It may not be reproduced, stored in a retrieval system, distributed or transmitted, in whole or in part, in any form or by any means.
Copyright 2013. Downloaded from SAE International by Walter Goelles, Tuesday, February 19, 2013 06:55:17 AM
剩余55页未读,继续阅读














安全验证
文档复制为VIP权益,开通VIP直接复制

评论1