New Functions, New Sensors, New Architectures – How to Cope with the Real-Time Requirements [chapter]

Tapio Kramer, Ralf Münzenberger
2009 Advanced Microsystems for Automotive Applications 2009  
The detection of the omni-present event chains in embedded applications goes far beyond functional modelling and static analysis. Once identified the analysis of their dynamics reveals a lot of data about the system like stability, critical paths or load reserves for future extensions. By using Task-Models and a real-time simulation tool the detection and analysis of event chains is very easy. Especially in distributed and collaborative development environments this is very helpful in reaching
more » ... ot only functional perfect systems but also delivering a high level of real-time quality. High Quality in Spite of Growing Complexity The majority of the upcoming smart system technologies and Information and Communication Technologies (ICTs) in the automotive industry combine existing and new sensors, build new distributed functions and require networked architectures. They span multiple domains and break up the existing one-vendor-one-box-principle. But how can such a complex system be architected and built to reach high quality levels in short cycles while combining several technologies and contributing parties? The aspired high quality covers different aspects. The dominant aspect is functional quality. This is well served by established methods and tools like model driven development. Often the process starts with requirements gathering, model creation, implementation in code. It can end at different levels of integration. Parallel to this a variety of quality tests are specified and executed to assure that the system matches the requirements at a high functional quality. But quality also demands reliability and robustness. The system shall generate the correct functional results at the desired point in timereliably, repeatable and under all circumstances. These timing and robustness aspects do not share the same level of tool support so far. Nevertheless they do have a tremendous impact on the system's quality and on the development time. This paper will describe how distributed embedded systems' softand hardware can be modelled to describe their dynamic real-time behaviour. These models can be executed and visualized on the real-time simulator chronSim or analyzed by the real-time validator chronVal. The execution timing, events and sequence of functions and communication is calculated and displayed in various diagrams. The worst case and distribution of execution times can be determined for single functions or complete systems. In an example from the automotive industry a system will be discussed, where a function is implemented on multiple control units using FlexRay for inter processor communication. The application tasks generating and receiving data run asynchronous to the FlexRay bus on separate control units due to application specific cycles.
doi:10.1007/978-3-642-00745-3_29 fatcat:apggwvb4jfbuzaqmljl4mco5e4