【正文】 52的定時(shí)計(jì)數(shù)器T1對(duì)脈沖信號(hào)進(jìn)行計(jì)數(shù)，用定時(shí)計(jì)數(shù)器T0進(jìn)行定時(shí)，每10ms產(chǎn)生一個(gè)中斷對(duì)數(shù)碼管進(jìn)行刷新，產(chǎn)生500個(gè)中斷后（即5s），進(jìn)行一次轉(zhuǎn)速處理，再通過(guò)單片機(jī)對(duì)T1的脈沖數(shù)進(jìn)行運(yùn)算轉(zhuǎn)換后，用四連數(shù)碼管顯示電機(jī)的轉(zhuǎn)速。片內(nèi)的高增益反相放大器通過(guò)XTALXTAL2外接，作為反饋元件的片外晶體振蕩器與電容組成的并聯(lián)諧振回路構(gòu)成一個(gè)自激振蕩器，向內(nèi)部時(shí)鐘電路提供振蕩時(shí)鐘。 時(shí)鐘電路連接圖 復(fù)位電路單片機(jī)的RST引腳為復(fù)位（Reset）端。TLX低5位溢出則向THX進(jìn)位，THX計(jì)數(shù)溢出則置位TCON中的溢出標(biāo)志位TFX。為了簡(jiǎn)化硬件電路，降低成本，在單片機(jī)應(yīng)用系統(tǒng)中常采用動(dòng)態(tài)掃描的方法，解決多位LED顯示的問(wèn)題。則可達(dá)到“同時(shí)”顯示各位不同的數(shù)字或字符的目的。匯編語(yǔ)言更接近機(jī)器語(yǔ)言，常用來(lái)編制與系統(tǒng)硬件相關(guān)的程序，如訪問(wèn)I/O端口、中斷處理程序、實(shí)時(shí)控制程序、實(shí)時(shí)通信程序等；而數(shù)學(xué)運(yùn)算程序則適合用C51高級(jí)語(yǔ)言編寫(xiě)，因?yàn)橛酶呒?jí)語(yǔ)言編寫(xiě)運(yùn)算程序可提高編程效率和應(yīng)用程序的可靠性[15]。C語(yǔ)言具有很好的可移植性和硬件控制能力，表達(dá)和運(yùn)算能力也較強(qiáng)。4． 表達(dá)方式靈活。為了提高編制計(jì)算機(jī)系統(tǒng)和應(yīng)用程序的效率，改善程序的可讀性和可移植性，在此采用高級(jí)語(yǔ)言編程[16]。當(dāng)Flag_calc=1時(shí)，將脈沖的數(shù)值由十六進(jìn)制轉(zhuǎn)換成十進(jìn)制，按轉(zhuǎn)速轉(zhuǎn)換公式轉(zhuǎn)換后，載入數(shù)據(jù)緩沖區(qū)。 原程序代碼 采用MCS—52C語(yǔ)言編寫(xiě)源程序:include define uchar unsigned chardefine uint unsigned intdefine ulong unsigned longdefine LED_DAT P1sbit pin_SpeedSenser = P3^5。 //時(shí)間計(jì)數(shù)器bit Flag_Fresh = 0。//初始化定時(shí)器T0void init_timer0()。 //d定時(shí)器 T0用于數(shù)碼管的動(dòng)態(tài)刷新 //TH0 = 0xC0。if(TcounterTIME_CYLC){ Flag_clac = 1。Disbuf[3] = 0。 // 定時(shí)刷新數(shù)碼管顯示 if(Flag_clac) { Flag_clac = 0。//脈沖計(jì)數(shù)清零 }}}//在數(shù)碼管上顯示一個(gè)四位數(shù)void DisplayFresh(){P2=P2amp。P2=P2|0xf0。Delay(1)。 LED_DAT = table[Disbuf[2]]。0xef。}//計(jì)算轉(zhuǎn)速，并把結(jié)果放入數(shù)碼管緩沖區(qū)void ClacSpeed(){uint speed 。//據(jù)公式計(jì)數(shù)轉(zhuǎn)速 Disbuf[0] = (speed/1000)%10。}//初始化定時(shí)器T0void init_timer0(){TMOD amp。 C/T0=0。 /* init values */TL0 = 0x00。 /* timer0 run */}//延時(shí)函數(shù)void Delay(uint ms){uchar i。}//初始化定時(shí)器T1void init_timer1(){TMOD amp。 C/T0=1。 /* init values */TL1 = 0x00。 /* timer1 run */}第5章 系統(tǒng)仿真與電路實(shí)現(xiàn) 系統(tǒng)仿真系統(tǒng)結(jié)合Keil ，通過(guò)Proteus來(lái)仿真。Keil ，編譯C語(yǔ)言源程序，并生成16進(jìn)制文件和列表文件。模擬器使用簡(jiǎn)單，結(jié)合了許多標(biāo)準(zhǔn)調(diào)試特征，包括多斷點(diǎn)、單步以及代碼執(zhí)行跟蹤等能力[17]。由于偉福編譯過(guò)程沒(méi)有Keil ，能對(duì)程序進(jìn)行直接編譯，省去了建立和設(shè)置工程等步驟，使用方便、快捷。Proteus ISIS 是英國(guó)Lab center 公司開(kāi)發(fā)的電路分析與實(shí)物仿真軟件。仿真結(jié)果為4r/min，符合設(shè)計(jì)要求，可按此仿真電路指導(dǎo)實(shí)際硬件電路的搭建。此計(jì)數(shù)器的最大計(jì)數(shù)脈沖數(shù)為63336（216），若每秒鐘計(jì)算一次，則當(dāng)1秒內(nèi)外部脈沖的輸入數(shù)超過(guò)65536個(gè)時(shí)，計(jì)數(shù)器會(huì)溢出，從而產(chǎn)生中斷，使得測(cè)出的轉(zhuǎn)速值小于實(shí)際的轉(zhuǎn)速值。若要使單片機(jī)準(zhǔn)確讀取外部脈沖，則脈沖的輸入周期不能超過(guò)3us。改進(jìn)方法：（1）采用時(shí)鐘頻率更高、定時(shí)/計(jì)數(shù)器位數(shù)更多的單片機(jī)來(lái)處理脈沖，現(xiàn)某些高速單片機(jī)可達(dá)到40MHz的處理速度，可以大大提高測(cè)速范圍。 長(zhǎng)沙學(xué)院畢業(yè)設(shè)計(jì)(論文) 參考文獻(xiàn)[1]王福瑞．單片微機(jī)測(cè)控系統(tǒng)設(shè)計(jì)大全[M]．北京航空航天大學(xué)出版社，1999:49[2]張勇．電機(jī)拖動(dòng)與控制[M]．機(jī)械工業(yè)出版社，2001[3]邵群濤，徐余法．電機(jī)及拖動(dòng)基礎(chǔ)[M]．機(jī)械工業(yè)出版社，2002:250269[4]馬西秦．自動(dòng)檢測(cè)技術(shù)[M]．機(jī)械工業(yè)出版社，2001:210230[5]2000年全國(guó)中小型電機(jī)學(xué)術(shù)年會(huì)論文集[C][6]余永權(quán)，汪明慧，黃英．單片機(jī)在控制系統(tǒng)中的應(yīng)用[M]．電子工業(yè)出版社，2003[7][M].清華大學(xué)出版社，2006:1020[8] 李剛，林凌. 新概念單片機(jī)教程(M).天津大學(xué)出版社，2007[9](M).高等教育出版社，2003:120124[10]雷思孝，馮育長(zhǎng)．單片機(jī)系統(tǒng)設(shè)計(jì)及工程應(yīng)用(M).西安電子科技大學(xué)出版社，2005:7985[11]（第2版）(M).中國(guó)計(jì)量出版社，2009:254259[12]郭培源，（M）.北京航空航天大學(xué)出版，2006:221224[13]（C51版）（M）.中國(guó)水利水電出版社，2007:112115[14] [J]. 傳感器技術(shù)2003，22(10):4547 [15]（M）.北京郵電大學(xué)出版社，2005:17[16]徐瑋，徐富軍，（M）.機(jī)械工業(yè)出版社，[17]王為青， Cx51應(yīng)用開(kāi)發(fā)技術(shù)（M）.人民郵電出版社，2007:3138[18]林志琦，郎建軍，李會(huì)杰，（M）.北京航空航天大學(xué)出版，2006:15致 謝在此次畢業(yè)設(shè)計(jì)中,首先要感謝劉安玲、袁媛老師對(duì)我的細(xì)心指導(dǎo)，遇到困難能夠及時(shí)給予幫助。在他們的親切關(guān)懷下，我不斷豐富著自己，在知識(shí)上不斷掌握新的理論與技能，在做人做事中充滿信心與勇氣，也逐漸形成了正確而成熟的人生觀、價(jià)值觀，這些對(duì)即將走出校園的我來(lái)說(shuō)是一筆很好的財(cái)富。 學(xué)生簽名： 日 期： 1 2010屆本科生畢業(yè)設(shè)計(jì)（論文）資料第二部分 外文資料翻譯Novel Rotation Speed Measurement Concept forABS Appropriated for Microsystem CreationSergey Y. Yurish, Nikolay V. Kirianaki, Nestor O. ShpakInstitute of Computer Technologies,Bandera str., 12, 290013, Lviv, UkraineTel.: +380 322 97 16 74, fax: + 380 322 97 16 41 syurishAbstract1. IntroductionToday’s cars have bee puter networks on wheels. The average car has about $653 worth of electronics and/or electromechanical systems, about 15 percent of the total value of the car [1]. By the year 2000, the average car will contain about $ 950 to $ 2,000 worth of electronics, depending on whether valuation is based on cost or price. It is estimated that electronics will make up 25 to 30 percent of a car’s total value [1]. Automotive microsystem applications, especially for antilock braking systems(ABS), require highreliability parts that can withstand the harsh environment and wide temperature range. On the other hand, their price should not be excessively high in conditions of large production volumes. The reliability of the ABS is determined by speed of processing of measuring information and solution making by the control system. In other words, the ABS must work in the real time. However, in many ABS, the measurement of rotation speed is based on the conventional methods of frequency measurement (standard direct and indirect counting methods) or on reciprocal (ratiometric) counting method [2]. The choice of measurement technique in the known traditional solutions depends on the desired resolution and dataacquisition rate. For maximum dataacquisition rate, periodmeasurement techniques are used. Maximum resolution and accuracy are obtained using frequency measurement. On the nature, the time of measurement and conversion for such methods (except the indirect method of measurement for low frequencies) is redundant in the all specified measuring range of frequencies, except the nominal one.The key point of the Paper is a reliable ABS solution (smart sensor encoder adaptive method of measurement for rotation speed), which satisfied to all requirements for the modern midrange (four wheels) and highend (integrated vehicle dynamics) ABS at lowering the cost of the system (Figure 1.).Figure 1. Three main ponents of ABS wheel speed sensing concept2. Smart Wheel Speed SensorSensor technology is playing a critical role in the development of new products and can govern the feasibility of deploying certain systems [3]. The critical sensors involved are those for sensing wheel rotation speed [4].The active inductive sensor with frequency output was selected as the wheel rotation speed sensor [5]. The rectangular impulse sequence is generated on the sensor39。 50 measurements per second at d = % and 250 184。s output frequency by the following dependence:(where z = 44 is the number of teeth), the sensor can be us