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Today's vehicle networks are mainly based on the event-triggered CAN-bus. In future FlexRay, which is a TDMA-based bus, will more and more be used for the implementation of safety-relevant real-time systems due to its determinism. In order to configure a CAN-based network the priorities of the messages sending via the external bus have to be defined. In this paper an approach will be presented allowing automated priority determination. Subsequently it will be shown how to adapt this method to automated cycle configuration in case of a FlexRay-based system. In order to ensure determinism not only in TDMA-based but also in event-triggered networks, a method will be presented adapting priorities of messages intending to exceed their deadline. This can be easily realized without changing the CAN protocol.

In this paper two new approaches are presented how to partition an amount of functions distributed in automotive electronic systems. In contrast to common partitioning algorithms as Kernighan-Lin, Best-Gain-First, Simulated-Annealing, a.s.o., these algorithms are real multi-partitioning ones. With respect to ECU (electronic control unit) characteristics, the software functions to be partitioned will be allocated automatically onto the available hardware. Main motivation is the reduction of the resulting bus-load which is provoked by the communication between such functions. Moreover these algorithms optimize the final partitioning solution to achieve a reduced number of ECUs. Reducing bus-load and the number of ECUs can lead to significant cost reduction. In order to validate partitioning results, a CAN as well as a FlexRay model was developed in Matlab/Simulink determining the bus-load over time.

In this paper we present the results of a project that concentrates on the design of distributed embedded systems for control-related applications. The OPTMAP (Optimal Mapping of Virtual Control Functions to a Distributed Architecture) framework supports the function allocation based on given constrains involving a feasible solution. The control systems we will consider use a time-triggered paradigm for sensor reading and event-driven behavior for inter-processor communication. Sensor values are read at fixed periods in time and data processing occurs after the control unit receives the proper message. The aim of the project is to get an optimized mapping which minimizes information traffic on the network and guarantees that all processing units are able to handle the distributed control functions in real time.

The aim of OSEK/VDX is an industry standard for open architectures in vehicles. Originally founded as a Franco - German joint project, OSEK/VDX is now drawing worldwide attention. In the project, services and protocols are specified to standardize Communication, Network Management and a real-time Operating System. Its architecture offers a network-independent interface while taking into account the constraints of automotive applications in terms of size and cost. A structured and modular software implementation based on standardized interfaces and protocols as proposed by OSEK/VDX is a necessary condition for portability and extendibility, and thus reusability of existing software. An overview of the current status of OSEK/VDX is presented.

The new aerial communication protocol “Controller Area Network” (CAN) efficiently supports distributed realtime control in automotive applications. In order to unload CPUs from high-speed message transfer, dedicated CAN hardware handles messages up to the communication object level. In multiplex wiring message rates are one to two orders of magnitude lower, allowing to implement the upper communication level more cost-effectively in software. This reduces CAN interface hardware to bitwise protocol handling only. It may be incorporated even into low-end microcontrollers without significantly increasing chip size. Thus the same CAN protocol supports the entire range of serial automotive communication, matching implementation costs to requirements at each performance level.