Research On Automotive Real-Time Operating System Conforming To OSEK

With wide application of electronic and computer technology into automobile, many luxury vehicles have more than 70 microprocessors installed, and automobile has already entered into the era of intelligence. The European automobile industry put forward OSEK/VDX standard, which broke the closed software development mode of world automotive industry, and met the requirements of increasingly large and complex vehicle electronic control software development, furthermore, it also achieved the portability of application software and the compatibility of control modules from different vendors.This paper described the OSEK/VDX standard and focused on analysing OSEK OS specification and modules, and then the paper analysed the kernel of the embedded real-time operating system uC/OS-II, and mainly analysed the mechanisms of task management as well as communication and synchronization amongdifferent tasks.The focus of this paper is to improve the uC/OS-II according to OSEK OS specification, and the specific improvements are as follows:(1)According to the definition of OSEK OS, numerical value 0 is defined as the lowest priority of task, and a larger value represents a higher priority. In contrast, a larger value in the uC/OS-II represents a lower task priority, and Numerical value 0 is defined as the highest priority. In order to conform to the OSEK OS specification after improving the system, it needs to change the priority judging method of the operating system;(2)In the uC/OS-II, it has only one task within a same level of priority, which means that it doesn't support multiple tasks within a same level of priority. However, the OSEK OS specification defines the consistent class BCC2 and ECC2, which provided that the same level of priority should support several tasks, and these tasks are scheduled in FIFO order. Therefore, it needs to change the task management mechanism of the operating system;(3) In order to solve the problem of priority inversion, OSEK OS specification proposed the priority ceiling protocol, hence it needs to improve the uC/OS-II to support it that the OSEK OS provided.Finally, the modified operating system is tested on the X86 platform, and the results of the test has also been analysed. The test contents are shown as follows:(1) Testing the correctness of task priority determinant method of the improved operating system;(2) Testing whether the modified operating system support multi-tasks within a same level of priority,and whether these tasks are scheduled in FIFO order. (3) Testing whether the modified operating system support the priority ceiling protocol which the OSEK OS specification provided.