Real-time operating systems are widely used in the field of communication and information , and plays an extremely important role . The well-known real-time operating system VxWorks, WinCE, μClinux, μC / OS-II , etc. . The papers choose μC / OS-II as the object of study because it is the source code is open , the kernel compact . μC / OS-II real-time operating system as a priority-based preemptive kernel task scheduling algorithms , high efficiency , fast task switching . ΜC / OS-II real-time operating system , there are some disadvantages : the priority of any task can not be the same , for the tasks that need to be run at the same time can only increase the complexity of the program development task to achieve synchronization . This article is based on these shortcomings μC / OS-II operating system , μC / OS-II operating system task scheduling improvements. ΜC / OS-II operating system improvements can create the same priority task , the same priority task time round-robin scheduling policy , priority tasks still use priority-based preemptive scheduling mechanism . This paper studies the μC / OS-II operating system architecture , focusing on to analysis task scheduling mechanism , and then analyze and solve the round-robin scheduling add the same priority task time slice , the need to address the problem , and then to achieve the same priority time slice round robin scheduling policy improvements and related functions . Finally, the improved results to verify the analysis.
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