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With the expansion of the field of real-time applications, real-time applications is increasing coverage, from low-end to high-end demand has applications, which give modern embedded real-time operating system (ERTOS) research has raised new demands and challenges. Traditional embedded real-time operating system designed with integrated, efficient large core structure. System functions concentrated in the kernel implementation, the kernel provides applications with high efficiency of the system call and good system response time. Traditional design methods for embedded real-time operating system it has its good side, but now embedded real-time operating system still lags behind demand, mainly in the real-time operating system, scalability, portability the new structure of the hardware platform support and interface standards openness, but also a large core structure system design for functional extensions often cause kernel modifications indeed affect the whole body. In order to solve these problems, we adopt a new approach and a new architecture to build the operating system. In the operating system of the study, mainly from the operation of the model and the storage model, the operating system to improve performance. The core work of this paper is to propose the concept and execution flow micro-kernel design, and on this basis, with the help of modern software engineering techniques, particularly the development of object-oriented methods and techniques to design and implement an object-based operating system, while at the ARM7TDMI-based embedded devices were implemented and tested. This thesis work mainly from the following aspects: the analysis of existing technologies and systems, operating system architecture design and prototype system implementation and performance testing. This paper analyzes a variety of related technologies and systems, including: a single large kernel operating system microkernel operating system, a single address space operating system, can be customized kernel, library-based operating system, a permanent operating systems, etc., for the subsequent studies and discusses the theoretical and technical foundation laid. Nanokernel basic abstraction is the flow of execution, as a basis, we have designed an object-based nanokernel embedded real-time operating system architecture. Which nanokernel layers, namely sodium nuclear layer, in order to further improve the timeliness; Carolina nuclear layer, both the use of a compilation of efficiency, but also has a modular features, including for processing task scheduling, interrupt management, and some use in system management data structures and corresponding treatment, IPC modules. Satisfied that the main achievement of low-level nuclear layer device drivers and time-critical code, with fewer task context switching time is faster, as well as micro-kernel layer provides services. MKRTOS we developed an object-based nanokernel prototype system, which includes the basic functions of the kernel, now in the ARM7TDMI-based embedded systems implemented and tested. Test results indicate that the object-based nanokernel embedded real time operating system has good real-time, information hiding, code reusability, portability, and scalable advantages.
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