Research And Design Of Real-time Embedded System Development Platform

With the rapid development industrial automation, real-time embedded system applications in the aerospace, engineering and military technology is becoming increasingly popular. In many embedded operating systems, Linux has been widely used in embedded systems, because Linux is powerful, supports various architectures, open source and modularize designs etc.. But the practical application of Linux in real-time environment is limited because of its non-preemptive kernel, coarse time granularity, frequently interrupt disable. It’s necessary to modify the original Linux to meet the real-time requirements.Firstly, the need for real-time system concepts and features were investigated, while inadequate for Linux on the real-time performance is analyzed, the necessity of real-time transformation was proposed. On this basis, the current variety of embedded Linux operating system real-time solutions are analyzed and compared, which focuses on the implementation mechanism of Xenomai. The real-time systems was built in the beaglebone black platform and real-time performance has been tested, and the test results of the standard Linux kernel were compared and analyzed.On the basis of the defect analysis of the Ethernet’s characteristics in real-time communication environment, the way to achieve real-time communication based on the Ethernet through using the network protocol stacks on Xenomai was proposed. The CPSW+LAN8710’s real-time driver has been written according to the RTnet driver model to transplant RTnet to the beaglebone black platform.Finally, the standard Linux network subsystem and RTnet-based real-time network performance were comparative tested and analysised. The test results indicate that, through applying Xenomai and RTnet on Linux, Real-time system has been significantly improved to meet the application requirements in the hard real-time environment, and build a common basic development platform of real-time embedded systems.