Serial Communication past, present and future

1
Serial Communication-past, present and future

• Automotive Electronics International Conference
  Munich, June 4-5 2003
• Sven Larsson
• Mecel AB
• sven.larsson_at_mecel.se

2
Serial communication - Overview

• FlexRay/TTP

• Safe-by-Wire/BST

• IEEE 1394

• MOST

• WLAN

• Bluetooth

• D2B

• CAN

• VAN

• J1850

• Proprietary

• LIN

• ISO-9141

Year
85
90
80
95
00
05
10
3
The first 10 years

• Proprietary protocols commonly used
• First simple point-to-point communication links
  already in 1982
• By 1986 in several High-end cars
• Lot of different concept systems were built
• Learning some new engineering skills
• functional specification, serial communication
  and distributed systems engineering
• Electrical systems specification design
• up until now a single persons work

4
Functional specification anno 1985
5
Standardisation work begins...

• Establishing a common view by definition of
  Multiplex categories
• SAE Class A Low Speed Control
• e.g. Control of Exterior Lamps, Typical lt 10
  kBit/s
• SAE Class B Data Communications
• e.g. Sharing of Parametric Data, Typical lt 50
  kBit/s
• SAE Class C High Speed Real Time Control
• e.g. High Speed link for distributed processing
• Typical lt 1 MBit/s
• Focus on Physical and DataLink level

6
ISO Standardisation work

• ISO High Speed 125 kBit/s lt Bitrate lt 1Mbit/s
• ISO Low Speed Bitrate lt 125 kBit/s
• CAN
• Main candidate for ISO High Speed
• Thoroughly examined in all aspects
• Only small modifications compared to original
  proposal 29 Bit ID and Enhanced bit-timing
• VAN
• Proposed as a low-cost alternative to CAN for
  bit-rates up to 250 kBit/s
• Manchester bit-coding In frame response to
  allow for low cost peripheral modules
• J1850
• Proposed by Japan US

7
Standardisation results

• Standards for Data Networking
• ISO High Speed CAN
• ISO Low Speed CAN VAN
• US/Japan SAE J1850
• Standards for Diagnostic communication
• European OEMs ISO 9141
• US/Japan OEMs J1850

8
During the 90-ties

• Focus on Powertrain Body multiplexing
• First European OEMs used CAN in Powertrain
  systems
• Prometheus - Grand Final at BMM Paris 1994
• Many of the Demonstrator Vehicles used the CAN
  bus for advanced future concepts

• CAN quickly adopted outside Automotive
• Integrated CAN modules in small 8 bit
  uControllers
• CAN also used for body networks at 50-125 kBit/s
• Proprietary high level protocols
• OSEK standardisation work
• OS, Network Management, Communication

9
Present situation

• CAN - Well established and will remain in a
  dominant position for many years

• LIN - Recently developed low cost alternative to
  CAN for small local networks
• This was once the reason for VAN

• MOST - Recently introduced for Infotainment
  systems in Europe

• Bluetooth - Automotive wireless networks
• Mating Automotive and Personal Area Networks

10
Candidates for the near future

• IEEE 1394 - Alternative to MOST?
• WLAN - Complement to Bluetooth?
• FlexRay/TTP - Candidates for X-by-wire
  applications
• Safe-by-Wire/BST - Dedicated for Safety Restraint
  Systems
• What will shape the future ?

11
New Technology - enabler for functionality growth
Functionality
By-wire?
Introduction of new technology
Infotainment
Multiplex
Electronics
Time
12
New Technology - The down side...
Complexity Cost
Mature
Introduction of new technology
By-wire?
Infotainment
Multiplex
Electronics
Time
13
Can we make it smoother?

• Efficient Standardisation
• Leverage established technologies when possible
• Where is the driving force?
• Complete application development platforms
  available at introduction
• Tools, methods, processes, s/w h/w building
  blocks

14
Conclusions

• Increased functionality is the main driving force
  for introduction of new communication concepts
• Higher level of abstraction and complete platform
  solutions
• Increased maturity at time of introduction
• Strive for longer technology lifetimes
• Higher level of abstraction and more predictable
  QoS means increased bus bandwidth and computing
  recourses
• Leverage technologies outside Automotive when
  possible
• Focus on making them Automotive grade

15
And the very last page.

• The Automotive Industry has walked a long way
  during the last 20 years, and we can be very
  proud of what we have achieved so far
• It is a complex product provided to a mass
  market, with extremely high demands on quality,
  and Automotive Grade gives us respect outside
  automotive
• Let us continue that way and intensify our
  co-operation to ensure the conformance to our
  customers expectations
• And finally, let us be humble and realise that
  even though we today has a very high competency
  in many fields, we still may benefit from
  competencies that other industries can provide