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1、<p><b>  附錄A</b></p><p>  Embedded Linux-based acquisition system</p><p>  With the rapid development of information technology, people need to accurate, fast and convenient acc

2、ess to large amounts of data and be able to quickly extract useful information. Embedded Systems is the IT network technology and a new direction of technology development. American futurist Timor predicted during his vi

3、sit to China in 1999: 4 ~ 5 years after the tool will be embedded PC and the Internet is the second greatest invention after. 20th century 90's, the application of embedded techn</p><p>  The development

4、 of embedded technology makes it easy to develop embedded systems, reducing development costs, generic products increased to replacement. Combination of the traditional embedded systems are small, energy-less, anti-inter

5、ference ability, stable characteristics, the development of embedded data acquisition system products, whether as a stand-alone product, or a function of a system of modules, all It is very meaningful.</p><p&g

6、t;  Data Acquisition System is a computer, communications and electronic technology, industrial control for an integrated detection system. This paper introduces embedded Linux-based data acquisition system hardware arch

7、itecture and software design. To enhance the system to respond to the real-time performance and multi-task processing capability of hardware used in the ARM9 microprocessor technology, at the same time Linux operating sy

8、stem migration, system reliability and scalability can be improv</p><p>  Embedded system is application-centric, based on computer technology, software, hardware can be tailored to meet the application syst

9、em functions, reliability, cost, size, power consumption, there are strict requirements of a dedicated computer systems, operating systems and features will integrated software systems in computer hardware, in a nutshell

10、 is the system software and hardware integration, the work is similar to the way BIOS with software code in small, highly automated, fast response </p><p>  Acquisition Data Acquisition System at the scene t

11、o complete the task. Acquisition system designed for distributed control systems, PC systems and on-site testing of the communication between digital serial based. Normal run-time, on-site detection of the controller to

12、complete the next-bit data acquisition, data processing, data storage, data distribution and other tasks. System has a certain degree of self-detection, self-tuning capabilities, to unusual circumstances to the PC, in or

13、der to mai</p><p>  Micro-computer's storage space smaller, while the standard Linux is a PC, and the need for the process of reducing the Linux kernel. For some added or removed independently of the fun

14、ction block can be retained only the kernel embedded system the functionality required to support the module, remove unwanted features. In order to meet certain real-time requirement and should not shield the kernel virt

15、ual memory management mechanism for enhanced real-time Linux. Computer systems are X86 motherboar</p><p>  Embedded Linux-based data acquisition system board design, mainly by a motherboard and a plug-9 moth

16、erboard. All the plug-3U structure, the module dual-socket connection between the module system motherboard linked to improve the reliability of the entire device. One plug-in boards for signal acquisition and processing

17、; additional plug-ins for the 8-channel signal conditioning board (a three-way on-board processing circuit, a total of 24 road, you can approach the basis of sensor signals, change</p><p>  From field device

18、s through a variety of sensor signals into low-noise cable channel signal conditioning board, each channel signal conditioning board that contains the three-channel signal conditioning. According to different types of se

19、nsors with different channel signal conditioning board, a variety of signals after signal conditioning for the same after the transformation of the voltage signal specifications. Signal processing flow is as follows: the

20、 sensor output signal voltage amplification</p><p>  Embedded Linux system from the perspective of software generally can be divided into four levels.</p><p>  (1) boot loader. Including the cur

21、ing of the firmware boot code (optional) and two major Bootloader. (2) core. Board-specific customization of embedded cores, as well as control of kernel boot parameters. (3) file system. Including the root fil

22、e system and the establishment of the Flash memory devices on the file system. It is a management system to provide a variety of configuration files and system implementation of user applications to run a good carrier of

23、 the environment. (4)</p><p>  System beginning in 2004 in the company's thermal power plant, BOF steel plant, power plants and other industrial application site. Practice shows that the embedded Li

24、nux-based data acquisition system to run stable and reliable.</p><p><b>  附錄B</b></p><p>  基于Linux的嵌入式采集系統(tǒng)</p><p>  隨著信息技術(shù)的飛速發(fā)展,人們需要能夠準(zhǔn)確、快速和便捷地獲得大量數(shù)據(jù)并能從中迅速提取出有用的信息。嵌入式系統(tǒng)

25、是繼IT網(wǎng)絡(luò)技術(shù)之后,又一個(gè)新的技術(shù)發(fā)展方向。美國著名未來學(xué)家葛洛龐帝1999年訪華時(shí)預(yù)言: 4~5年后嵌入式能工具將是繼PC和因特網(wǎng)之后最偉大的發(fā)明。進(jìn)入20世紀(jì)90年代,嵌入式技術(shù)的應(yīng)用全面展開,目前已成為通信和消費(fèi)類產(chǎn)品的主要平臺(tái)技術(shù)。在自動(dòng)控制領(lǐng)域,不僅可以用于ATM機(jī)、自動(dòng)售貨機(jī)、工業(yè)控制等專用設(shè)備和移動(dòng)通信設(shè)備、GPS、娛樂等相結(jié)合,嵌入式系統(tǒng)同樣發(fā)揮巨大的作用。</p><p>  嵌入式技術(shù)的發(fā)展

26、使得開發(fā)嵌入式系統(tǒng)變得容易,開發(fā)成本降低,產(chǎn)品通用性提高,可更新?lián)Q代。結(jié)合傳統(tǒng)嵌入式系統(tǒng)體積小、耗能少、抗干擾能力強(qiáng)、穩(wěn)定的特點(diǎn),開發(fā)嵌入式數(shù)據(jù)采集系統(tǒng)的應(yīng)用產(chǎn)品,不管是作為一個(gè)獨(dú)立的產(chǎn)品,還是某一系統(tǒng)的某個(gè)功能模塊,都是十分有意義的。</p><p>  數(shù)據(jù)采集系統(tǒng)是集計(jì)算機(jī)、通信及電子技術(shù)、工業(yè)控制為一體的綜合探測系統(tǒng)。本文介紹了基于嵌入式Linux 的數(shù)據(jù)采集系統(tǒng)的硬件結(jié)構(gòu)和軟件設(shè)計(jì)。為提高系統(tǒng)的實(shí)時(shí)響應(yīng)

27、性能和多任務(wù)處理能力,在硬件上采用ARM9 微處理器技術(shù),同時(shí)移植Linux操作系統(tǒng),使系統(tǒng)的可靠性和可擴(kuò)展性得以提高。設(shè)計(jì)中充分利用了嵌入式Linux 的特點(diǎn)。系統(tǒng)軟件模塊有數(shù)據(jù)采集模塊、數(shù)據(jù)處理模塊、數(shù)據(jù)通信模塊和數(shù)據(jù)診斷模塊。將嵌入式Linux 操作系統(tǒng)引入數(shù)據(jù)采集系統(tǒng)的設(shè)計(jì)中,加速了系統(tǒng)的開發(fā),方便了將來的功能擴(kuò)展,提高了觀測數(shù)據(jù)的及時(shí)性和準(zhǔn)確性,實(shí)現(xiàn)了觀測的自動(dòng)化。</p><p>  嵌入式系統(tǒng)是以應(yīng)

28、用為中心、以計(jì)算機(jī)技術(shù)為基礎(chǔ)、軟件硬件可裁剪、適應(yīng)應(yīng)用系統(tǒng),對(duì)功能、可靠性、成本、體積、功耗有嚴(yán)格要求的專用計(jì)算機(jī)系統(tǒng),它將操作系統(tǒng)和功能軟件集成于計(jì)算機(jī)硬件系統(tǒng)之中,簡而言之就是系統(tǒng)的應(yīng)用軟件與系統(tǒng)的硬件一體化,類似于BIOS的工作方式,具有軟件代碼小,高度自動(dòng)化,響應(yīng)速度快等特點(diǎn)。特別適合于要求實(shí)時(shí)和多任務(wù)的體系。嵌入式系統(tǒng)是將先進(jìn)的計(jì)算機(jī)技術(shù)、半導(dǎo)體技術(shù)、電子技術(shù)和各個(gè)行業(yè)實(shí)際應(yīng)用相結(jié)合的產(chǎn)物。嵌入式系統(tǒng)的結(jié)構(gòu)由兩大模塊組成:硬件

29、平臺(tái)和軟件平臺(tái)。</p><p>  嵌入式系統(tǒng)是以應(yīng)用為中心、以計(jì)算機(jī)技術(shù)為基礎(chǔ)、軟件硬件可裁剪、適應(yīng)應(yīng)用系統(tǒng),對(duì)功能、可靠性、成本、體積、功耗有嚴(yán)格要求的專用計(jì)算機(jī)系統(tǒng),它將操作系統(tǒng)和功能軟件集成于計(jì)算機(jī)硬件系統(tǒng)之中,簡而言之就是系統(tǒng)的應(yīng)用軟件與系統(tǒng)的硬件一體化,類似于BIOS的工作方式,具有軟件代碼小,高度自動(dòng)化,響應(yīng)速度快等特點(diǎn)。特別適合于要求實(shí)時(shí)和多任務(wù)的體系。嵌入式系統(tǒng)是將先進(jìn)的計(jì)算機(jī)技術(shù)、半導(dǎo)體技術(shù)

30、、電子技術(shù)和各個(gè)行業(yè)實(shí)際應(yīng)用相結(jié)合的產(chǎn)物。</p><p>  數(shù)據(jù)采集系統(tǒng)的采集任務(wù)在現(xiàn)場完成。采集系統(tǒng)設(shè)計(jì)為分布式的控制系統(tǒng),系統(tǒng)上位機(jī)與現(xiàn)場檢測下位機(jī)之間的通信基于串口。正常運(yùn)行時(shí),現(xiàn)場下位檢測控制器完成數(shù)據(jù)采集、數(shù)據(jù)處理、數(shù)據(jù)存儲(chǔ)、數(shù)據(jù)發(fā)送等多種任務(wù)。系統(tǒng)具有一定的自檢測、自校正能力,能將異常情況傳給PC機(jī),以便維護(hù)。為了適應(yīng)各種不同情況對(duì)焊縫自動(dòng)檢測的要求,整個(gè)檢測系統(tǒng)采用模塊化結(jié)構(gòu)設(shè)計(jì),可應(yīng)用不同的模

31、塊組合成不同的應(yīng)用系統(tǒng)。</p><p>  微型計(jì)算機(jī)的存儲(chǔ)空間較小, 而標(biāo)準(zhǔn)Linux是面向PC 的,需要對(duì)Linux 內(nèi)核進(jìn)行裁減。對(duì)一些可獨(dú)立加上或卸下的功能塊,可在編譯內(nèi)核時(shí)僅保留嵌入式系統(tǒng)所需的功能支持模塊, 刪除不需要的功能。為了滿足一定的實(shí)時(shí)性要求,需屏蔽內(nèi)核的虛擬內(nèi)存管理機(jī)制來增強(qiáng)的Linux實(shí)時(shí)性。系統(tǒng)中微機(jī)主板屬于X86體系結(jié)構(gòu),兼容一般桌面PC的Linuxi386版本。這樣,我們可以直接使

32、用X86體系的編譯器對(duì)Linux核心源代碼直接進(jìn)行編譯及裁剪,并避免了對(duì)Linux 核心源代碼中涉及CPU的部分模塊以及內(nèi)存管理模式模塊的修改。增加了文件系統(tǒng)和GUI根據(jù)系統(tǒng)需要,文件系統(tǒng)應(yīng)包括: 基本文件系統(tǒng)結(jié)構(gòu)、基本應(yīng)用程序、基本配置文件、基本設(shè)備/dev/hd* 和/dev/tty*、基本程序運(yùn)行所需的函數(shù)庫。GUI 是軟件可視化設(shè)計(jì)不可缺少的,也為將來的現(xiàn)場檢修維護(hù)提供可視化的界面。編寫Linux的引導(dǎo)代碼, 將diskonch

33、ip作為系統(tǒng)的啟動(dòng)設(shè)備,引導(dǎo)代碼放在diskonchip上。系統(tǒng)加電后,由引導(dǎo)代碼進(jìn)行基本的硬件初始化,然后把內(nèi)核經(jīng)映像裝入內(nèi)存運(yùn)行。嵌入式系統(tǒng)的硬件平臺(tái)通常以緊湊、專用性強(qiáng)的處理器為核心,</p><p> ?。?)體積小:在嵌入式系統(tǒng)的主體應(yīng)用場合,如手持設(shè)備,智能儀器儀表,家用電器等均對(duì)體積有較高限制,要求盡量少占用空間。(2)存儲(chǔ)容量小:嵌入式系統(tǒng)一般以ROM,FLASHMEMORY、RAM等作為存儲(chǔ)介質(zhì)

34、,由于價(jià)格及嵌入式系統(tǒng)體積等因素限制,因而不可能有太大的存儲(chǔ)容量。(3)良好的性能價(jià)格比:很多嵌入式設(shè)備是嵌入于宿主設(shè)備以輔助宿主設(shè)備高效地完成其功能,因而性價(jià)比要求較高,以防止過分提高宿主設(shè)備成本。</p><p>  基于Linux的嵌入式數(shù)據(jù)采集系統(tǒng)采用板卡式設(shè)計(jì),主要由一塊母板個(gè)插件和一個(gè)母板。各插件全部采用3U背插式結(jié)構(gòu),各模件采用雙插座連接方式,各模件之間通過系統(tǒng)內(nèi)部母板相聯(lián)系,提高了整個(gè)裝置的可靠性

35、。其中一個(gè)插件為信號(hào)采集處理板;另外的8個(gè)插件為信號(hào)調(diào)理通道板(一塊板上三路調(diào)理電路,總共24路,可以根據(jù)傳感器的信號(hào)路數(shù),增減信號(hào)調(diào)理通道板)。系統(tǒng)的結(jié)構(gòu)緊湊,整面板設(shè)計(jì),外形美觀大方。系統(tǒng)由信號(hào)調(diào)理系統(tǒng)和信號(hào)采集、處理系統(tǒng)兩部分構(gòu)成。信號(hào)調(diào)理系統(tǒng)由電荷放大、電壓放大或電流放大電路(視傳感器類型定)、程控放大、程控低通濾波、緩沖放大等四級(jí)電路組成,其中由單片機(jī)控制上位機(jī)要求的程控放大、程控低通濾波等參數(shù)。信號(hào)采集、處理系統(tǒng)擬采用ARM

36、+FPGA結(jié)構(gòu)來實(shí)現(xiàn)。此種結(jié)構(gòu)的好處是:硬件開發(fā)平臺(tái)難度較小,系統(tǒng)軟件升級(jí)容易實(shí)現(xiàn)。</p><p>  取自現(xiàn)場設(shè)備的各種傳感器信號(hào)通過低噪音電纜送入信號(hào)調(diào)理通道板,每個(gè)信號(hào)調(diào)理通道板上包含三個(gè)信號(hào)調(diào)理通道。根據(jù)不同的傳感器類型配備不同的信號(hào)調(diào)理通道板,各種信號(hào)經(jīng)過信號(hào)調(diào)理后都變換為同一規(guī)格的電壓信號(hào)。信號(hào)處理流程如下:傳感器輸出的信號(hào)經(jīng)過電壓放大、電流放大或電荷放大等(視傳感器類型定)變換為電壓信號(hào),該電壓信

37、號(hào)經(jīng)程控放大、程控低通濾波,最后再經(jīng)過緩沖放大處理,輸出電壓信號(hào)送給信號(hào)采集、處理板。</p><p>  嵌入式Linux系統(tǒng)從軟件的角度看通??梢苑譃?個(gè)層次。</p><p>  (1)引導(dǎo)加載程序。包括固化在固件中的啟動(dòng)代碼(可選)和Bootloader兩大部分。</p><p> ?。?)內(nèi)核。特定于嵌入式板子的定制內(nèi)核以及控制內(nèi)核引導(dǎo)系統(tǒng)的參數(shù)。<

38、/p><p>  (3)文件系統(tǒng)。包括根文件系統(tǒng)和建立于Flash內(nèi)存設(shè)備之上的文件系統(tǒng)。它是提供管理系統(tǒng)的各種配置文件以及系統(tǒng)執(zhí)行用戶應(yīng)用程序良好運(yùn)行環(huán)境的載體。</p><p> ?。?)用戶應(yīng)用程序和驅(qū)動(dòng)。特定于用戶的應(yīng)用程序和驅(qū)動(dòng)程序。有時(shí)在用戶應(yīng)用程序和內(nèi)核層之間可能還會(huì)包括一個(gè)嵌入式圖形用戶界面。</p><p>  系統(tǒng)從2004年開始在公司下屬的的熱電廠

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