抢占式实时多任务微内核的设计与应用
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摘要
在进入后PC时代以来，各种嵌入式实时操作系统(RTOS)如雨后春笋般的涌现出来，各大厂商都推出拥有自主知识产权的所谓“通用化”的RTOS。但是，通用化的RTOS往往由于其通用性，考虑应用的方方面面，所以必然要牺牲某方面性能为代价的。因此，RTOS向着超内核(Hyper-Kernel)、安全核(SecurityKernel)、防危核(Safety Kernel)和特定应用的嵌入式实时操作系统ASOS(Application Specific Operating Systems)等方向发展。
本论文的研究工作是根据ASOS的设计原理，采用基于模式的生成方法，在嵌入式实时多任务微内核μC／OS-Ⅱ基础上，分析微内核的构成机理；然后，分析如何采用实时UML建模工具来进行MT_UCOS微内核的设计；最后，形成完整的MT_UCOS微内核架构体系，并编写了微内核的主要功能代码。
MT_UCOS微内核是基于μC／OS-Ⅱ的用于执行少量任务的ASOS型微内核。它设计的用途是基于Internet网的中低端产品的应用。在本论文写作前完成的实际工作有：研习公开源代码的嵌入式实时操作系统如μC／OS-Ⅱ和RT-Linux，分析不同内核架构的设计机理；比较通用RTOS的优缺点；结合ASOS的设计特点，将μC／OS-Ⅱ进行改造性移植试验。
在本论文中可以得到如下结果：
(1)在μC／OS-Ⅱ基础上进行改进优化后形成MT_UCOS内核源代码。
(2)在ARM公司提供的μHAL组件库的基础上，开发基于ASOS型的硬件抽象层。
(3)提出实时任务分割原理，并在MT_UCOS中给出了相关的实现机制。
(4)最后从嵌入式系统设计的角度开发设计了电话数码录音机，将MT_UCOS微内核进行实例化的应用。
(5)而且，在嵌入式系统软件MT_UCOS微内核设计，以及在电话数码录音机的设计中，运用实时UML工具进行相关建模，形成相应的设计图例和文档。
总之，本论文在理论上尝试将设计模式和UML引入嵌入式系统软件开发中，在实际中将ASOS型MT_UCOS微内核进行实例化应用，所以本论文的选题是具有一定的理论和实际意义。
When Post-PC draws near, all kinds of Embedded Real-time Operating Systems (abr. RTOS) flush out. Every powerful corporations issue their registered and so-called general-purpose RTOS, which maybe sacrifice its performance such as real-time features or transplantation because it has to show the consideration for the generality in applications. And then, the Development of RTOS wells up two new concepts of Hyper-kernel and ASOS that is the abbreviation of Application Specific Operating Systems
The major research work about the thesis is as follow. Firstly, it analyzes the structural mechanism of micro-kernel based on the embedded real-time multi-tasking micro-kernel, C/OS-II, guided by the design theory of ASOS and adopting the building method grounded on design pattern. Secondly, it describes how to design MT_UCOS micro-kernel by real-time UML modeling notations. And finally, it forms a down-to-earth architecture of MT_UCOS micro-kernel, and lists the major functional codes.
MT_UCOS as one of the ASOS RTOSes is a micro-kernel for minority tasks based on uC/OS-II, which is design to be used in low and middle ends embedded products in the Internet. The basic research work finished before writing this dissertation includes studying the open-source RTOSes such as uC/OS-II and RT-Linux, analyzing the design mechanisms in different kernel architectures, comparing the advantages and disadvantages of general-purpose RTOSes, transplanting and reconstructing the C/OS-II kernel on the test platform under the direction of ASOS design's characteristics.
This paper gives some results as follows:
(1) Programming the MT_UCOS kernel resource codes after improving and optimizing the uC/OS-II kernel;
(2) Developing a hardware abstract layer of ASOS style founded on the HAL components library offered by ARM Corporation;
(3) Putting forward the principles of real-time task splitting, and furthermore, offering the realizable mechanism in MT_UCOS;
(4) Finally, designing and developing a telephone digital recorder (Dictaphone) from the view of embedded system design, and instantiating the application of MT_UCOS micro-kernel;
(5) And what's more, using real-time UML notations in the modeling both during the course of embedded system software MT_COS micro-kernel design and Dictaphone design, and accordingly documenting the design diagrams and documentation.
All in all, this thesis tries to apply the design pattern and UML notations in embedded system software development theoretically, on the other hand, instantiates the ASOS MT_UCOS micro-kernel in practice, so it maybe favors the RTOS design both in theory and practice a little more
本论文的研究工作是根据ASOS的设计原理，采用基于模式的生成方法，在嵌入式实时多任务微内核μC／OS-Ⅱ基础上，分析微内核的构成机理；然后，分析如何采用实时UML建模工具来进行MT_UCOS微内核的设计；最后，形成完整的MT_UCOS微内核架构体系，并编写了微内核的主要功能代码。
MT_UCOS微内核是基于μC／OS-Ⅱ的用于执行少量任务的ASOS型微内核。它设计的用途是基于Internet网的中低端产品的应用。在本论文写作前完成的实际工作有：研习公开源代码的嵌入式实时操作系统如μC／OS-Ⅱ和RT-Linux，分析不同内核架构的设计机理；比较通用RTOS的优缺点；结合ASOS的设计特点，将μC／OS-Ⅱ进行改造性移植试验。
在本论文中可以得到如下结果：
(1)在μC／OS-Ⅱ基础上进行改进优化后形成MT_UCOS内核源代码。
(2)在ARM公司提供的μHAL组件库的基础上，开发基于ASOS型的硬件抽象层。
(3)提出实时任务分割原理，并在MT_UCOS中给出了相关的实现机制。
(4)最后从嵌入式系统设计的角度开发设计了电话数码录音机，将MT_UCOS微内核进行实例化的应用。
(5)而且，在嵌入式系统软件MT_UCOS微内核设计，以及在电话数码录音机的设计中，运用实时UML工具进行相关建模，形成相应的设计图例和文档。
总之，本论文在理论上尝试将设计模式和UML引入嵌入式系统软件开发中，在实际中将ASOS型MT_UCOS微内核进行实例化应用，所以本论文的选题是具有一定的理论和实际意义。
When Post-PC draws near, all kinds of Embedded Real-time Operating Systems (abr. RTOS) flush out. Every powerful corporations issue their registered and so-called general-purpose RTOS, which maybe sacrifice its performance such as real-time features or transplantation because it has to show the consideration for the generality in applications. And then, the Development of RTOS wells up two new concepts of Hyper-kernel and ASOS that is the abbreviation of Application Specific Operating Systems
The major research work about the thesis is as follow. Firstly, it analyzes the structural mechanism of micro-kernel based on the embedded real-time multi-tasking micro-kernel, C/OS-II, guided by the design theory of ASOS and adopting the building method grounded on design pattern. Secondly, it describes how to design MT_UCOS micro-kernel by real-time UML modeling notations. And finally, it forms a down-to-earth architecture of MT_UCOS micro-kernel, and lists the major functional codes.
MT_UCOS as one of the ASOS RTOSes is a micro-kernel for minority tasks based on uC/OS-II, which is design to be used in low and middle ends embedded products in the Internet. The basic research work finished before writing this dissertation includes studying the open-source RTOSes such as uC/OS-II and RT-Linux, analyzing the design mechanisms in different kernel architectures, comparing the advantages and disadvantages of general-purpose RTOSes, transplanting and reconstructing the C/OS-II kernel on the test platform under the direction of ASOS design's characteristics.
This paper gives some results as follows:
(1) Programming the MT_UCOS kernel resource codes after improving and optimizing the uC/OS-II kernel;
(2) Developing a hardware abstract layer of ASOS style founded on the HAL components library offered by ARM Corporation;
(3) Putting forward the principles of real-time task splitting, and furthermore, offering the realizable mechanism in MT_UCOS;
(4) Finally, designing and developing a telephone digital recorder (Dictaphone) from the view of embedded system design, and instantiating the application of MT_UCOS micro-kernel;
(5) And what's more, using real-time UML notations in the modeling both during the course of embedded system software MT_COS micro-kernel design and Dictaphone design, and accordingly documenting the design diagrams and documentation.
All in all, this thesis tries to apply the design pattern and UML notations in embedded system software development theoretically, on the other hand, instantiates the ASOS MT_UCOS micro-kernel in practice, so it maybe favors the RTOS design both in theory and practice a little more
引文
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[2]Bruce Powel Douglass．实时UML开发嵌入式系统高效对象(第二版)．北京：中国电力出版社，2003
[3]Michael Melkonian[文]．张铁冰[译]．编写自己的实时操作系统．单片机与嵌入式系统应用(合订本)，2002(1-6)
[4]atree.Vxworks内核分析．http://www.cetinet.com/
[5]党红梅．几种实时操作系统的比较．http://hichun.nease.net/cmp-os.htm/
[6]Arnold BerBer[著]，吕骏[译]．嵌入式系统设计．北京：电子工业出版社，2002
[7]郑竑宇，宋寅卯．运用UML分析设计占先式实时内核．单片机与嵌入式系统应用，2003年9期
[8]倪敏，周怡廷等．上海自动化仪表股份有限公司．uC／OS-Ⅱ的任务切换机理及中断调度优化．单片机及嵌入式系统应用，2004年1期
[9]Jean J．Labrosse[著]，邵贝贝等[译]．嵌入式实时操作系统．北京：北京航空航天大学，2003
[10]彭良清．简易非抢占式实时多任务操作系统的设计与应用．单片机与嵌入式系统应用(合订本)，2002(1-6)
[11]凌阳科技．MiniOS用户操作手册V1.2．北京：凌阳大学计划推广中心，2003
[12]肖踞雄．嵌入式系统硬件抽象层的建立及软件的可移植性设计．单片机与嵌入式系统应用，2003年7期
[13]高建平，何超等．通过任务分割提高嵌入式系统的实时性．单片机及嵌入式系统应用，2004年1期
[14]孙彦景，马小平，李鹏．实时操作系统中的板级支持包BSP．单片机与嵌入式系统应用(合订本)，2002(1-6)
[15]郑宗汉．实时系统软件基础：北京：清华大学出版社，2003
[16]薛涛，龚光华，绍贝贝．在MOTOROLA 568XX系列DSP上运行BC／OS-Ⅱ单片机与嵌入式系统应用(合订本)，2002(1-6)
[17]高晓超．嵌入式操作系统实时机制研究．南京航空航天大学，2003年3月
[18]Erich Gamma[著]．李英军，马晓星等[译]．设计模式：可复用面向对象软件基础．北京：机械工业出版社，2000
[19]王飞跃，吴朝晖．ASOS：嵌入式操作系统的发展趋势．计算机世界．2003年
[20]马忠梅，马广云等．ARM嵌入式处理器结构与应用基础．北京：北京航空航天大学出版社，2002
[21]Wayne Wolf[著]．孙玉芳等[译]．嵌入式计算系统设计原理．北京：机械工业出版社，2002
[22]王学龙．嵌入式Linux系统设计与应用．北京：清华大学出版社，2001
[23]陈章龙，涂时亮等．嵌入式系统-Intel StrongARM结构与开发．北京：北京航空航天大学出版社，2002
[24]21Steve Furber[著]．田泽，于敦山等[译]．ARM Soc体系结构．北京：北京航空航天大学，2002
[25]王田苗主编．嵌入式系统设计与实例开发——基于ARM微处理器与μC／OS-Ⅱ实时操作系统(第二版)．北京：清华大学出版社，2003
[26]William Stallings[著]．魏迎梅，王涌等[译]．操作系统-内核与设计原理(第四版)．北京：电子工业出版社，2002
[27]Rochit Rajsuman[著]．于敦山，盛世敏等[译]．Soc设计与测试．北京：北京航空航天大学，2003
[28]桑楠．嵌入式系统原理及应用开发技术．北京：北京航空航天大学出版社，2002
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