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In a distributed system, the synchronization of tasks executed in different nodes is necessary. Therefore, we propose a method of synchronization of tasks in a distributed system using FlexRay. FlexRay is expected to become a dominant protocol in automotive systems. It supports a clock synchronization mechanism. We present two methods for synchronization of tasks using a clock synchronized by FlexRay. One is a synchronization method for the start point of tasks. The other is a synchronization method for specific points in the task. We implement the proposed method as an experiment.

Nowadays, electronic control units (ECUs) have more and more importance on the value of modern automobiles. This trend is causing the complexity of the overall systems to increase and make the development cycles longer. In order to address these problems, strategies to reuse software and a growing emphasis to develop hardware/software co-simulation schemes are gathering strength. The software reuse allows modular design aspects to be promoted and helps in limiting the development efforts needed. The hardware/software co-simulation enables early validation, easy robustness evaluation of the system and reduces the overall development cycles. This article proposes the development and adoption of software reusable blocks that can be in the hardware and/or software domains. The proposed blocks contain the common characteristics of several communication protocols. In this paper, we develop the CAN communication protocol by using the proposed softwarepsilas reusable common blocks and added block that has some protocol specialized characteristics and compare the simulation results with real CAN signals from 16-bit embedded system for ECUs.

The gateway system is an essential component for network-to-network communication using different protocols inside a distributed system. Since reliability is an important aspect in an automotive system, here we propose a method for improving the reliability of the gateway system by using OSEK/VDX and duplication scheme. Three factors were considered for improving the reliability of the gateway. First, a high priority message must be processed first. Second, the gateway should not transmit messages to erroneous nodes that cannot receive messages by checking the accessibility of the destination node. Third, a sub-gateway should be used alternately with the main gateway when the main gateway cannot operate correctly. In this study, we developed a CAN and FlexRay gateway embedded system and applied the proposed method to this system.

Developing and validating a distributed system requires great cost, time, and effort than a centralized system because the systems are inherently concurrent, asynchronous, and nondeterministic. For this reason, accurate simulation function is significantly important for developing the distributed system. In particular, it finds applications in the automobile embedded system industry, which requires short time-to-market. If the simulation function is able to simulate the hardware characteristics of the distributed system, the accuracy of the simulator increases. We develop a 16-bit embedded system for an electronic control unit (ECU) in an automobile system and a block for modeling and simulating for distributed system with considering of hardware characteristics, especially caused by network characteristics. In this paper, consequence of simulation with real-value in the 16-bit embedded system is compared.