【正文】 圖所示41。我們?nèi)〔煌碾娮柚?，就得到不同的電容測(cè)量的量程。 軟件設(shè)計(jì)流程 主程序流程圖本次設(shè)計(jì)主要是應(yīng)用單片機(jī)的中斷與計(jì)數(shù)的功能，通過INT0,T0，對(duì)555振蕩電路產(chǎn)生的正玄波進(jìn)行計(jì)數(shù)[12]，在單片機(jī)內(nèi)部經(jīng)過數(shù)據(jù)的計(jì)算與處理得到被測(cè)電容的大小值，再將數(shù)據(jù)傳送出去最后由LCD1602a進(jìn)行顯示[14]。開始 T0，INT0初始化有無按鍵N啟動(dòng)555YY有無按鍵有無中斷YNN啟動(dòng)計(jì)數(shù)器T0有無中斷顯示電容值計(jì)算電容的大小停止計(jì)數(shù)器圖42 主程序設(shè)計(jì)流程圖 中斷子程序流程圖通過一個(gè)測(cè)量按鍵啟動(dòng)整個(gè)測(cè)量程序，當(dāng)有按鍵按下時(shí)，中斷開始并且555芯片開始工作[13]，通過外部中斷零INT0來控制計(jì)數(shù)器T0的開始和停止，INT0采用邊沿觸發(fā)方式，在第一個(gè)脈沖邊沿啟動(dòng)T0，使T0開始計(jì)數(shù)，在第二個(gè)脈沖邊沿停止T0計(jì)數(shù)，并且中斷返回。中斷開始555工作T0開始計(jì)數(shù)T0停止計(jì)數(shù) 中斷返回 圖43 中斷子程序流程圖 顯示子程序當(dāng)單片機(jī)計(jì)算出被測(cè)電容值后，、R/W、E引腳。開始的首先檢測(cè)一下是否為忙。當(dāng)RS為0時(shí)，R/W為0時(shí)，E至高電平后為0時(shí)，往LCD寫入指令代碼。顯示子程序流程圖如圖44所示。編寫程序是一個(gè)相當(dāng)復(fù)雜的過程，要求編程人員具有很強(qiáng)邏輯思維，而且要在對(duì)整個(gè)系統(tǒng)工作原理相當(dāng)熟悉的基礎(chǔ)上面才能完成任務(wù)。尤其是使用C語言編寫程序[15]的時(shí)候更是要注釋，因?yàn)镃語言是一門比較高級(jí)的語言，C語言比較的煩瑣。 結(jié)果分析通過仿真得到如下數(shù)據(jù)表格表41 電容測(cè)量值與實(shí)際值的比較被測(cè)電容值 測(cè)量值 通過表中的數(shù)據(jù)可以看出仿真的數(shù)據(jù)還是比較準(zhǔn)確的，但是在實(shí)際的操作中，測(cè)量值可能沒有這么準(zhǔn)確，因?yàn)樵趯?shí)際的電路中，555芯片輸出的方波可能不會(huì)如仿真時(shí)的那么標(biāo)準(zhǔn)平滑，波形不會(huì)那么理想，再加上單片機(jī)的測(cè)量也會(huì)存在一些誤差，所以綜合以上的一些考慮，真實(shí)中的測(cè)量結(jié)果肯定要比仿真中的結(jié)果誤差大。第5章 結(jié) 論畢業(yè)論文是一次非常好的將理論與實(shí)際相結(jié)合的機(jī)會(huì)，通過對(duì)電容測(cè)試儀的課題設(shè)計(jì)，鍛煉了我的實(shí)際動(dòng)手能力，增強(qiáng)了我解決實(shí)際工程問題的能力，同時(shí)也提高我查閱文獻(xiàn)資料、設(shè)計(jì)規(guī)范以及電腦制圖等其他專業(yè)能力水平。而采用單片機(jī)可以提高系統(tǒng)的可靠性和穩(wěn)定性，縮小系統(tǒng)的體積,調(diào)試和維護(hù)方便。系統(tǒng)的軟件部分是系統(tǒng)實(shí)現(xiàn)功能的關(guān)鍵，軟件部分是在Keil51的平臺(tái)上使用是C語言編寫程序?？傊麄€(gè)系統(tǒng)的工作正常，完成了設(shè)計(jì)任務(wù)的全部要求雖然本設(shè)計(jì)完成了設(shè)計(jì)任務(wù)，但無法得到十分精確的測(cè)量結(jié)果，這主要是有以下幾點(diǎn)原因，首先單片機(jī)對(duì)于脈沖寬度的測(cè)量精確度有限，其次是外界的干擾對(duì)波形有一定的影響，還有硬件自身也有一部分原因。參考文獻(xiàn)[1] 楊素行. 模擬電子技術(shù)基礎(chǔ)簡明教程(第三版).高等教育出版社.[2] 李群芳，肖看. 單片機(jī)原理接口及應(yīng)用技術(shù)[M]. 北京：清華大學(xué)出版社，2009：36～47.[3] 周堅(jiān). 單片機(jī)輕松入門[M]. 第二版. 北京：北京航空航天大學(xué)出版社，2007：60～80.[4] 高峰. 單片微型計(jì)算機(jī)原理與接口技術(shù)[M]. 第二版. 北京：科學(xué)出版社，2009：15～20.[5] 趙廣林. 常用電子元器件識(shí)別/檢測(cè)/[M]. 電子工業(yè)出版社 3241.[6] 劉衛(wèi)國. C語言程序設(shè)計(jì)[M]. 北京：鐵道大學(xué)出版社，2008：30～41.[7] 徐愛鈞, 彭秀華. KeilCx51 [M] .電子工業(yè)出版社2004年3142. [8] 夏繼強(qiáng). 單片機(jī)實(shí)驗(yàn)與實(shí)踐教程. 北京：北京航空航天大學(xué)出版社, 2001. [9] 謝自美. 電子線路設(shè)計(jì)實(shí)驗(yàn)測(cè)試(第二版).武漢:華中理工大學(xué)出版社，2000.[10] Stephan innovations demanded by PCB tools:Industial Diamond Review[J],2004(3):32.[11] des Relations Intermationals[M] :Dalloz,1988.[12] 康華光. 《電子技術(shù)基礎(chǔ)》（模擬部分 第五版）[M]. 高等教育出版社, 2005.[13] 戴衛(wèi)恒. 51單片機(jī)C語言應(yīng)用程序設(shè)計(jì)實(shí)例精講[M]. 北京：電子工業(yè)出版， 致 謝此次設(shè)計(jì)實(shí)踐是本科四年來對(duì)自己所學(xué)知識(shí)的一個(gè)總結(jié)，其難度、復(fù)雜性、對(duì)設(shè)計(jì)的要求都是以前所不能比擬的。在此特別感謝楊老師，在此次設(shè)計(jì)中給予我很多幫助，是自己深刻認(rèn)識(shí)到了雖然自己要畢業(yè)了，可是自己要學(xué)習(xí)的東西還有很多很多，并對(duì)我要求嚴(yán)格，在各方面對(duì)我進(jìn)行細(xì)心指導(dǎo)，讓自己為馬上要參加工作打下了良好的基礎(chǔ)，在此表示誠摯的致意和衷心的感謝。還要特別感謝我的同學(xué)，正是與他們?cè)谠S多問題上的交流、討論，在他們的幫助之下，我的論文才得以順利完成。sZ80 is the first designed in accordance with this idea processor, then on the development of microcontroller and dedicated processors have parted ways.Single chip, also known as singlechip microcontroller, it is not plete a certain logic chips, but to a puter system integrated into a to a microputer, and puter than just the lack of a microcontroller I / O devices. General talk: a chip bees a puter. Its small size, light weight, cheap, for the study, application and development of facilities provided. At the same time, learning to use the MCU is to understand the principle and structure of the puter the best choice.SCM and the puter functions internally with similar modules, such as CPU, memory, parallel bus, the same effect as well, and hard disk memory devices, and different is its performance of these ponents were relatively weak many of our home puter, but the price is low , usually not more than 10 yuan you can do with it ...... some control for a class is not very plicated electrical work is enough of. We are using automatic drum washing machine, smoke hood, VCD and so on appliances which could see its shadow! It is primarily as a control section of the core ponentsIt is an online realtime control puter, controlline is that the scene is needed is a stronger antijamming ability, low cost, and this is, and offline puter (such as home PC), the main difference.Single chip MCU is through running, and can be modified. Through different procedures to achieve different functions, in particular special unique features, this is another device much effort needs to be done, some great efforts are very difficult to do. A not very plex functions if the 5039。s CD4000 series of these pure hardware buttoned, then the circuit must be a large PCB board! But if the United States if the 7039。s hard drive in terms of nothing, but in terms of the MCU is not acceptable. SCM in the utilization of hardware resources to be very high for the job so although the original is still in the pilation of a lot of use. The same token, if the giant puter operating system and applications run up to get home PC, home PC, also can not afford to.Can be said that the twentieth century across the three power era, that is, the age of electricity, the electronic age and has entered into the puter age. However, this puter, usually refers to the personal puter, referred to as PC. It consists of the host, keyboard, monitor and other ponents. Another type of puter, most people do not know how. This puter is to give all kinds of intelligent machines single chip (also known as microcontroller). As the name suggests, this puter system took only a minimal integrated circuit, can be a simple operation and control. Because it is small, usually hidden in the charged mechanical stomach in. It is in the device, like the human brain plays a role, it goes wrong, the whole plant was paralyzed. Now, this microcontroller has a very broad field of use, such as smart meters, realtime industrial control, munications equipment, navigation systems, and household appliances. Once all kinds of products were using SCM, can serve to upgrade the effectiveness of products, often in the product name preceded by the adjective intelligent, such as intelligent washing machines. Now some technical personnel of factories or other amateur electronics developers to engage in out of certain products, not the circuit is too plicated, that function is too simple and can easily be copied. The reason may be stuck in the product did not use a microcontroller or other programmable logic device.SCM historySCM was born in the late 20th century, 70, experienced SC