Research On The Period Assignment And Bus Access Configuration Algorithm In Design Of Automotive Electronics Software

In recent years, as the application of embedded computing technology, communication technology and other information technologies in automobiles,it has seen great evolutions in automotive fabricaton.The increase of automotive system's capability has entered a new era to apply the advanced electronic control technology, and all kinds of control technology's applications based on embedded software will be one of the development priorities of automotive technology.Software is the core of automotive electronics control systems,for the complexity of automotive electronics software is on the rise and the automobiles is sensitive to the cost,real-time and cost control problems are becoming more and more severe in it. Task's period and the Bus Access Configuration are decisive factors of the system's real-time property, CPU utilization,so through the adjustment of it,we can optimize the CPU utilization under the premise of guaranteeing real-time requirements.It can enhance the ECU's ability to accommodate the new applications and slow down the ECU's increasing,so it is meaningful to the cost control of automobiles.Task's period assignment and Bus Access Configuration are key parts of platform-based automotive electronics software design method,so we started from it and propsed the period assignment and bus access configuration algorithm.The main contributions of this thesis are as followes:1,we firstly introduce traditional automotive electronics software design,and give an analysis about its deficits.Based upon it we summarize the key challenges and trends of automotive electronics software design.And then we describe the platform-based automotive electronics software design and its design flow, and give a survey about the period assignment, bus access configuration and the relevant problems of that design flow.2,Based on the analysis mentioned before,we found that the current research about period assignment and Bus Access Configuration in embedded real-time systems are mostly about how to optimize the time-related properties,and there is little work related with CPU utilization optimization.So based on Geometric Programming, we propose a period assignment and Bus Access Configuration algorithm which can meet the requirements of real-time, bus slot utilization and schedulability constraints,and realize the optimization of CPU utilization.3,The problem mentioned before is a typical GP problem, so we combine GPPOSY toolbox,which can solve the GP problem,with matlab to simulate our algorithm.The simulation results shown this algorithm is effective in optimizing the CPU utilization while meeting the real-time property constraints.