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There are many applications in which you may need to reverse engineer the Controller Area Network (CAN), e.g.: Automotive competitor analysis Telematics applications such fleet management Disabled driver applications The typical reverse engineering process is concerned with moving a sensor and watching the CAN bus for message changes. For example, wind down a door window and see if this kicks off changes in CAN message data. Many CAN buses have many messages originating from many Electronic Control Units (ECUs). This means it is difficult to watch all of them at the same time. It would be far easier if you could simply watch a smaller number of CAN messages to observe changes by isolating the ECUs the messages originate from. This paper describes a process that allows the user to identify which CAN messages are transmitted by a particular ECU. This is achieved by getting the electrical signature of each CAN message and matching known CAN messages with unknown ones.

The paper discusses the development and implementation of a form of in-vehicle communications for the body control in an Ariel Atom niche sports car. A Local Interconnect Network (LIN) bus has been developed that runs the LIN signals over the power lines of the vehicle wiring harness. The LIN system has one master and up to 15 slave ECUs. LIN is normally run at a maximum bit rate of 20 Kbit/s, however this system has been implemented at 57.6 Kbit/s by modulating over the power lines. Benefits of this approach include weight reduction, reduction in the number wires, ease in retro-fitting to existing vehicle architectures as only requires a connection to power lines and the ability to monitor the signals via the battery pins of the OBD connector of the vehicle. The approach has resulted in a reduction in weight due to wiring and electronic control unit reduction.

With the current concerns over vehicle emissions, oil availability and pricing there is a lot of interest in environmentally friendly vehicles such as electric and hybrid electric as ways of reducing costs and CO₂ emissions. In the case of a pure electric vehicle it is important to optimize the electric vehicle range so that it can travel as far as possible and ultimately does not leave the user of the vehicle stranded without enough charge in the battery to complete the journey. For hybrid electric vehicles there is a lot of scope to optimize its control so that the optimal use of electricity and internal combustion engine is maintained, for example, maximization of the use of plug-in charging opportunities. For both vehicle types, optimal battery management is important.

Modern vehicle electrical architectures are extremely complex and based on large number of Electronic Control Units (ECUs) integrated with hardwiring or a network technology such as Controller Area Network (CAN), Local Interconnect Network (LIN) or FlexRay. Even a simple system such as a driver's door can contain a large number of control functions such as electric windows, electric mirrors, seat control switches and therefore a lot of internal wiring is required within the door system. To reduce cost, weight and complexity of the wiring harness, it is usual for some combination of CAN, LIN and hardwired connections to be used for electronics integration. The key problem with this is how to assess the potential for cost and weight saving of candidate architectures at the very early stage of the design process and therefore how to choose a particular electrical architecture.

Event Scheduled CAN (ESCAN) is a new, open sourced, scheduling protocol for CAN. The aims of the protocol are discussed, including the ability to optimise the available bandwidth over CAN and enable maximum bus loading as well as providing a worst case determinism for message reception. A number of potential applications for the protocol are covered as well as details of how ESCAN can be used to optimise existing higher layer protocols such as CANopen and J1939. A comparison with TTCAN is also discussed, including the benefits of ESCAN in terms of CPU utilisation, ROM and RAM requirements and the potential for cost savings that that brings while still providing the advantages of TTCAN. These advantages include a simple to implement basic protocol stack, no specialist hardware requirements needed to support the protocol other than a TTCAN compliant CAN controller (this is so that the retransmission of CAN frames can be disabled).

The objective of the research discussed in this paper is to propose a methodology for comparing candidate electrical architectures on a cost basis at the very beginning of the architecture design process. To achieve this objective, historical data concerning the cost of a wiring harness for a driver’s door electrical system is analysed along with information on an electrical architecture for the door system of a small four door passenger car. The study is focused around a driver’s door electrical system based on LIN and hardwired integration. However, it is concluded that the results are applicable to other types of automotive electrical architectures.

For a typical communications C-language software stack, its size in terms of ROM and RAM will be dependent upon the network properties such as number of nodes, schedules, messages and signals. A lot of this information is part of a more detailed design and during architecture selection only signal and nodal information will be available. Messages and schedule information will be part of a much more detailed part of the design process. The objective of the study described in this paper is to ascertain whether ROM and RAM requirements can be estimated from only node and signal information only as this is the information that tends to be available at the very beginning of the electrical architecture design process. Historical data from a LIN design and its associated communications stack is statistically analysed and used to develop a methodology for ROM and RAM requirement estimation.

To improve road safety the public sector is actively supporting this effort with investment in required infrastructure, enforcement in the road safety rules, and improved deployment of Intelligent Transportation Systems (ITS). With the development of more powerful processors, communication and sensor technologies, tools are now available to enable the industry players to meet the aforementioned challenges. The paper will describe work undertaken within the European MEDEA+ framework in the project SAPECS (Secured Architecture & Protocols for Enhanced Car Safety). The consortium of companies that worked within SAPECS broke down the requirements emerging from these complex automotive architectures into component specifications, and partitioning of software/hardware to optimise costs.

The Controller Area Network (CAN) has seen enormous success in automotive body and powertrain control systems, and in industrial automation systems using higher layer protocols such as DeviceNet and CANopen. Now, the CAN standard ISO11898 are being extended to Time Triggered CAN (TTCAN) to address the safety critical needs of first generation drive-by-wire systems. However, their successful development depends upon the availability of silicon and software support, and appropriate development & analysis tools. This paper outlines the current status of TTCAN technology and describes the implementation of Level 1 TTCAN on the Atmel 89c51cc01/cc02/cc03/cc04 microcontrollers. The descriptions contained show how to implement for different bus speeds, along with suggestion for a user to tailor the drivers for their own application. Level 2 TTCAN is also described for comparison purposes.

The Controller Area Network (CAN) has seen enormous success in automotive body and powertrain control systems, as well as industrial automation systems using higher layer protocols such as CANopen and DeviceNet. Now, the CAN standard ISO11898 is being extended to Time Triggered CAN (TTCAN) to address the safety critical needs of first generation drive-by-wire systems. However, their successful development depends upon the availability of silicon and software support, and appropriate development & analysis tools. Warwick Control Technologies and the University of Warwick are tasked with prototyping a TTCAN analyser within the European Union Media+ project Silicon Systems for Automotive Electronics (SSAE) consortium, and with funding from the British Department of Trade and Industry (DTI). This paper briefly outlines the current status of both CAN & TTCAN technology and describes the requirements of a TTCAN analyser over that of a traditional CAN analyser.