HomePage
Electronic-components
Embedded
Industry automation
Pneumatic
Test & measurement
Tools
Electromobility
Solar energy
Lighting
Jobs
Trade fairs, Events
Interesting video
Various
AR236.B & AR232.B
 
APAR AR236.B & AR232.B radio loggers
JZ-500 and JZ-500-C black
 
JZ-500 and JZ-500-C black cables manufac
HF41F
 
HF41F subminiature power relays from HON
GT-900B
 
GOLDTOOL toolsets in cases
Intel® Neural Compute Stick 2
 
RS Components announces availability of
MC4
 
MC4 solar connector sets
WIHA-SB24670
 
Multifunctional WIHA LED Torch
G2RV-SR
 
G2RV-SR interface relays from OMRON
LUP-20-LED
 
LUP-20-LED-SMD desktop magnifier
LinkSwitch™-XT2
 
Power Integrations Unveils High-Efficien

Addressing the challenge of debugging automotive Ethernet networks

Addressing the challenge of debugging automotive Ethernet networks

From infotainment to advanced driver assistance systems (ADAS), today’s vehicles rely on the flow of large volumes of data, a flow which is beginning to be constrained by the capacity of established automotive bus architectures such as CAN bus. In response, the automotive industry has developed a version of the ubiquitous Ethernet networking standard for use in vehicles.

However, debugging these automotive Ethernet networks is not a trivial task, which is leading developers to seek out new test solutions. The 100BASE-T1 Ethernet interface, based on BroadR-Reach technology, has now been standardized by the IEEE 802.3bw working group. Implementing automotive networks with this new standard brings a host of development changes, including the 100 Mbit/s data rate that is significantly greater than traditional bus systems.

Featuring full-duplex Ethernet communications over an unshielded Ethernet twisted pair, 100BASE-T1 signals have PAM-3 modulation and differential signal levels of between –1V and +1V. The transmitted signals have to be pre-distorted by an equalizer so that they can be carried reliably and with minimal RF leakage over an unshielded cable. It is this extensive pre-distortion applied to a 100BASE-T1 Ethernet signal that makes it difficult for developers to judge the effectiveness with which a bus is carrying data by simply analyzing its electrical signals.

Figure 1a : A differential 100BASE-Tx signal, showing its three levels and the steep edges at the signal transitions. Source: Rohde & Schwarz

Figure 1b:  An automotive 100BASE-T1 signal, showing how pre-distortion masks the three levels of the PAM-3 signal. Source: Rohde & Schwarz

The automotive Ethernet test challenge

Standardized compliance tests for 100BASE-T1 interfaces involve measuring electrical characteristics using an oscilloscope and network analyzer. An Ethernet protocol analysis tool that records all of the Ethernet data traffic can be used to verify that an electronic control unit (ECU) correctly handles communications. Beyond this, however, it is difficult to perform detailed root-cause analysis because transmission errors are only recorded as telegram errors.

To perform more in-depth analysis it becomes necessary to combine a suitable trigger and decode bundle with the chosen oscilloscope. By enabling developers to directly correlate electrical signals with the transmitted telegram content, for example, Rohde & Schwarz’s trigger and decode bundle for 100BASE-T1 makes it possible to debug bus issues in automotive Ethernet applications as easily as it has been traditionally for CAN bus implementations.

Addressing the testing challenge

Because 100BASE-T1 communication is based on simultaneous transmission of bi-directional data, any signal measurement on the bus extracts superimposed data streams. To analyze the two data streams, they must be separated, using directional couplers such as those found on the R&S RT-ZF5 Ethernet probing fixture. Inserting the probe in the Ethernet line separates the data streams, allowing an oscilloscope to be used for non-intrusive recording of the 100BASE-T1 communications.

Figure 2: The R&S RT-ZF5 Ethernet probe fixture separates the full-duplex data streams of 100BASE-T1 communications. Source: Rohde & Schwarz

Figure 3: 100BASE-T1 decoding of full-duplex communications. The MAC frame is colored while the idle frames are gray. Source: Rohde & Schwarz

The signal streams that the probe extracts are still subject to the pre-distortion imposed by the equalizer in the 100BASE-T1 transmitter to protect their transport over the unshielded twisted pair. The next step is for the oscilloscope to equalize the signals to return them to their undistorted state, and then extract and display the transmitted data telegrams and idle frames. Correlation of the 100BASE-T1 signals with the content of the telegrams - coupled with extensive triggering capabilities that can, for instance, be used to display isolated telegrams based on their source or destination addresses –enables the powerful analysis and diagnostic capabilities increasingly needed for automotive Ethernet.

Figure 4: This screenshot shows the two levels of the differential 100BASE-T1 signal correlated with the decoded telegram content. Source: Rohde & Schwarz

100BASE-T1 decoding

100BASE-T1 decoding provides a way of revealing the timing relationship between bus communications and other signals. For example, the start time of an ECU can be determined by measuring the length of time between triggering an oscilloscope on the 12V supply and the arrival of the first valid telegram. A similar approach can be used to verify the stability of communications over the bus. In this case, the scope is configured to trigger on short-term interruptions of the supply voltage, so the developer can analyze the number of bus anomalies that those interruptions cause.

Electromagnetic interference can cause sporadic bus errors that are difficult to debug without further analysis. However, the ability to decode 100BASE-T1 communications means that developers can analyze bus communications across all of the OSI protocol layers, using the timing correlation of the measurements to identify coupling from interference sources.

Consider the measurement shown in Figure 5 where the MAC and idle frames of a 100BASE-T1 signal are correctly transmitted at the start of the recording. The data stream is then interrupted. In the lower signal, the frequency spectrum of the interfering signal (area marked in gray) is plotted, showing the cause - an interference peak at 2MHz. This combination of protocol-specific decoding with the range of analysis tools provided by the oscilloscope (e.g. frequency spectrum) simplifies debugging of complex issues such as intermittent interference.

Figure 5: Pinpointing a sporadic interruption in bus communications by combining protocol analysis and frequency analysis. Source: Rohde & Schwarz

Summary

Automotive communications are becoming more complex as data rates rise. The emergence of the 100BASE-T1 automotive Ethernet standard is easing the bandwidth issues of existing in-vehicle bus systems, at the cost of more complex debug challenges.

Rohde & Schwarz has developed a trigger and decode bundle option for debugging 100BASE-T1 signals, which includes a probing fixture for nonintrusive signal access. This tool enables developers to correlate electrical signal measurements with the decoded contents of transmitted telegrams. As a result, users can analyze protocol content during debugging and quickly identify the causes of any bus errors that occur.

Author: Dr Ernst Flemming is the product manager for oscilloscopes at Rohde & Schwarz in Munich.

2019070911 / 09.07.2019 / Test & measurement / editor /

Addressing the challenge of debugging automotive Ethernet networks
Addressing the challenge of debugging automotive Ethernet networks
From infotainment to advanced driver assistance systems (ADAS), today’s vehicles rely on the flow of large volumes of data, a flow which is beginning to be constrained by the capacity of established automotive bus architectures such as CAN bus. In response, the automotive industry has developed a version of the ubiquitous Ethernet networking standard for use in vehicles.
.....
TAITRONICS 2019, Taipei, Taiwan, 16.10.-18.10.2019
.....
TAITRONICS 2019, Taipei, Taiwan, 16.10.-18.10.2019
electronicAsia 2019, Hong Kong, 13.10.-16.10.2019
electronicAsia 2019, Hong Kong, 13.10.-16.10.2019
.....
Hong Kong Electronics Fair, 13.10.-16.10.2019
.....
Hong Kong Electronics Fair, 13.10.-16.10.2019
SENSOR+TEST 2019 is nearly set to go
SENSOR+TEST 2019 is nearly set to go
About two months before the opening, the preparations are well underway for the SENSOR+TEST from 25 to 27 June 2019. At the Annual Press Conference of the AMA Association for Sensors and Measurement in Nuremberg, the organizer, Holger Bödeker, had a very positive outlook on this year’s internationally leading trade fair for sensor, measuring, and testing technology.
.....
SMTconnect, 7.5.-9..2019, Nuremberg
The SMTconnect brings together people and technologies from the areas of development, production, services, and applications in connection with electronic assemblies and systems.
.....
SMTconnect, 7.5.-9..2019, Nuremberg
MWC Shanghai 2019, 26.6.-28.6.2019
MWC Shanghai 2019, 26.6.-28.6.2019
Over 550 exhibitors will gather in Shanghai to showcase the most innovative products & services and the big ideas impacting the industry.
.....
CERAMICS EXPO 2019, 30.4.-1.5.2019, Cleveland, Ohio, USA
Ceramics Expo is the leading annual supply chain exhibition and conference for advanced ceramics and glass materials, manufacturing and components.
.....
CERAMICS EXPO 2019, 30.4.-1.5.2019, Cleveland, Ohio, USA
SEMICON TAIWAN, Taipei, 18.9.-20.9.2019
SEMICON TAIWAN, Taipei, 18.9.-20.9.2019
SEMICON Taiwan is not just a platform that connects Taiwan and global microelectronics ecosystems but also a bridge that facilitates smooth collaboration between the industry, the government, the academia, and research institutions. Entering its 24th anniversary, SEMICON Taiwan still stays true to its missions― Leading Technology Trends, Driving Technology Innovation, and Facilitating Collaboration and continues providing various channels and activities that meet the companies' marketing and promotion needs.
.....
NEPCON Japan, Tokio, 15.1.-17.1.2020
Asia's Leading Exhibition for Electronics R&D, Manufacturing and Packaging Technology
.....
NEPCON Japan, Tokio, 15.1.-17.1.2020
NEPCON Japan, Nagoya, 18.9.-20.9.2019
NEPCON Japan, Nagoya, 18.9.-20.9.2019
.....
BATTERY JAPAN, Osaka, 9.9.-11.9.2020
BATTERY JAPAN is world's leading international exhibition for rechargeable battery, showcasing various components, materials, devices, finished rechargeable batteries for rechargeable battery R&D and manufacturing. It is held twice a year in Tokyo (Feb.) and Osaka (Sep.).
.....
BATTERY JAPAN, Osaka, 9.9.-11.9.2020
BATTERY JAPAN, Osaka, 29.9.-1.10.2021
BATTERY JAPAN, Osaka, 29.9.-1.10.2021
BATTERY JAPAN is world's leading international exhibition for rechargeable battery, showcasing various components, materials, devices, finished rechargeable batteries for rechargeable battery R&D and manufacturing. It is held twice a year in Tokyo (Feb.) and Osaka (Sep.).
.....
AMA Center for Sensors and Measurement at the Hanover Fair
Specialized Technical Platform for Basic Elements in Automation
.....
AMA Center for Sensors and Measurement at the Hanover Fair
BATTERY JAPAN, Tokyo, 26.2.-28.2.2020
BATTERY JAPAN, Tokyo, 26.2.-28.2.2020
BATTERY JAPAN is world's leading international exhibition for rechargeable battery, showcasing various components, materials, devices, finished rechargeable batteries for rechargeable battery R&D and manufacturing. It is held twice a year in Tokyo (Feb.) and Osaka (Sep.).
.....
BATTERY JAPAN, Tokyo, 3.3.-5.3.2021
BATTERY JAPAN is world's leading international exhibition for rechargeable battery, showcasing various components, materials, devices, finished rechargeable batteries for rechargeable battery R&D and manufacturing. It is held twice a year in Tokyo (Feb.) and Osaka (Sep.).
.....
BATTERY JAPAN, Tokyo, 3.3.-5.3.2021
BATTERY JAPAN, Osaka, 25.9.-27.9.2019
BATTERY JAPAN, Osaka, 25.9.-27.9.2019
BATTERY JAPAN is world's leading international exhibition for rechargeable battery, showcasing various components, materials, devices, finished rechargeable batteries for rechargeable battery R&D and manufacturing. It is held twice a year in Tokyo (Feb.) and Osaka (Sep.).
.....
LIGHTFAIR 2019, Philadelphia, PA USA, 21.5.-23.5.2019
LIGHTFAIR® International is the world’s largest annual architectural and commercial lighting trade show and conference and is sponsored by the International Association of Lighting Designers (IALD) and the Illuminating Engineering Society (IES). The event is produced and managed by International Market Centers.
.....
LIGHTFAIR 2019, Philadelphia, PA USA, 21.5.-23.5.2019
Company of the week

TE Connectivity
Address Book


SMA Solar Technology AG


TE Connectivity


akYtec GmbH


SOS electronic s.r.o.


MARVELL


Taiwan Semiconductor


ROHM Semiconductor


ČEZ a.s.


Pickering Interfaces Ltd


ANRITSU


Mouser Electronics


NEXPERIA


RS Components GmbH


Transfer Multisort Elektronik Sp. z o.o.


SECTRON


FAULHABER


Willow Technologies


ABB


ACS Motion Control


Visual Communications Company, LLC


Sonderhoff Holding GmbH


LASER COMPONENTS


LEM


Hradil Spezialkabel GmbH


Radio Frequency Systems


Apacer Technology Inc.


Pico Technology


AERCO


MENCOM


Analog Devices
Calendary
NEPCON Japan, Nagoya, 18.9.-20.9.2019
SEMICON TAIWAN, Taipei, 18.9.-20.9.2019
BATTERY JAPAN, Osaka, 25.9.-27.9.2019
electronicAsia 2019, Hong Kong, 13.10.-16.10.2019
Hong Kong Electronics Fair, 13.10.-16.10.2019
TAITRONICS 2019, Taipei, Taiwan, 16.10.-18.10.2019
productronica 2019, Munich, DE, 12.-15.11.2019
NEPCON Japan, Tokio, 15.1.-17.1.2020
DistribuTECH, 28.1.-30.1.2020, San Antonio, TX
BATTERY JAPAN, Tokyo, 26.2.-28.2.2020
BATTERY JAPAN, Osaka, 9.9.-11.9.2020
IMTS2020, 14.9.-19.9.2020, Chicago, IL
ISE 2021, Barcelona, Spain, 2.2.-5.2.2021
DistribuTECH, 9.2.-11.2.2021, San Diego, CA
BATTERY JAPAN, Tokyo, 3.3.-5.3.2021
BATTERY JAPAN, Osaka, 29.9.-1.10.2021
DistribuTECH, 25.1.-27.1.2022, Dallas, TX
DistribuTECH, 7.2.-9.2.2023, San Diego, CA
DistribuTECH, 23.1.-25.1.2024, Indianapolis, IN
DistribuTECH, 11.2.-13.2.2025, Dallas, TX
Interesting video
The ISS Design Challenge ...
Interesting video
Mouser Electronics Warehouse Tour with Grant Imahara
naše portály dle jazyka:

česko/slovenská jazyková verze:
WWW.ELEKTRONIKA.CZ
WWW.ELEKTRONIK-INFO.CZ

anglická jazyková verze:
WWW.ELECTRONICA.ONLINE
WWW.ELECTRONIC-INFO.EU
WWW.COMPONENTS.ONLINE

polská jazyková verze:
WWW.ELEKTRONIKA.ONLINE/pl
WWW.ELEKTRONIK-INFO.PL

ruská jazyková verze:
WWW.ELEKTRONIKA.ONLINE/ru
WWW.ELEKTRONIK-INFO.RU
naše portály dle zaměření:

ELEKTRONIKA.ONLINE :
WWW.ELECTRONICA.ONLINE
WWW.ELEKTRONIKA.CZ
WWW.ELEKTRONIKA.ONLINE/pl
WWW.ELEKTRONIKA.ONLINE/ru

ELEKTRONIK-INFO:
WWW.ELECTRONIC-INFO.EU
WWW.ELEKTRONIK-INFO.CZ
WWW.ELEKTRONIK-INFO.PL
WWW.ELEKTRONIK-INFO.RU

COMPONENTS:
WWW.COMPONENTS.ONLINE
  kontakt:

MALUTKI media s.r.o.
Těrlická 475/22
735 35 Horní Suchá
tel. 00420-603531605
e-mail: info@malutki-media.com



All trademarks are the property of their respective owners.
ISSN 1801-3813