【正文】 類似于聲卡）。 在大型電路中，這種模塊化應(yīng)用極大地縮小了體積，簡(jiǎn)化了電路，降低了損壞、錯(cuò)誤率，也方便于更換。 （ 7） 單片機(jī)在汽車設(shè)備領(lǐng)域中的應(yīng)用 單片機(jī)在汽車電子中的應(yīng)用非常廣泛，例如汽車中的發(fā)動(dòng)機(jī)控制器，基于 CAN 總線的汽車發(fā)動(dòng)機(jī)智能電子控制器， GPS 導(dǎo)航系統(tǒng)， abs 防抱死系統(tǒng)，制動(dòng)系統(tǒng)等等。 此外，單片機(jī)在工商，金融 ，科研、教育，國(guó)防航空航天等領(lǐng)域都有著十分廣泛的用途。 5 AT89C52 單片機(jī)介紹 AT89C52 是美國(guó) Atmel 公司生產(chǎn)的低電壓、高性能 CMOS 8 位單片機(jī)，片內(nèi)含 8KB 的可反復(fù)擦寫的程序存儲(chǔ)器和 12B 的隨機(jī)存取數(shù)據(jù)存儲(chǔ)器（ RAM），器件采用 Atmel 公司的高密度、非易失性存儲(chǔ)技術(shù)生產(chǎn)，兼容標(biāo)準(zhǔn) MCS51指令系統(tǒng)，片內(nèi)配置通用 8 位中央處理器（ CPU）和 Flash 存儲(chǔ)單元，功能強(qiáng)大的 AT89C52 單片機(jī)可靈活應(yīng)用于各種控制領(lǐng)域。 AT89C52 單片機(jī)屬于 AT89C51 單片機(jī)的增強(qiáng)型，與 Intel 公司的 80C52 在引腳排列、硬件組成、工作特點(diǎn)和指令系統(tǒng)等方面兼容。 其主要工作特性是： 片內(nèi)程序存儲(chǔ)器內(nèi)含 8KB的 Flash程序存儲(chǔ)器， 可擦寫 壽命為 1000次 ； 片內(nèi)數(shù)據(jù)存儲(chǔ)器內(nèi)含 256字節(jié)內(nèi)部 RAM； 具有 32根可編程 I/O口線； 具有 3個(gè)可編程定時(shí)器； 2個(gè)可編程 I/O口線； 中斷系統(tǒng)具有 8個(gè)中斷源； 串行口是具有一個(gè)全雙工的可編程串行通信口； 低功耗工作模式有空閑模式和掉電模式； 具有可編程的 3級(jí)程序鎖定位； AT89C52最高工作頻率為 24MHz。 功能特性描述： AT89C52是 一種低功 耗、 高性能 CMOS8位微控制器 ， 具有 8K在系統(tǒng)可編程 Flash存儲(chǔ)器， 使用 Atmel公司的高密度、非易失性存儲(chǔ)技術(shù) 制造 ， 與工業(yè) 80C51產(chǎn)品指令和引腳完全兼容。片上 Flash允許程序存儲(chǔ)器在系統(tǒng)可編程，亦適用于常規(guī)編程器。在單芯片上，擁有靈巧的 8位CPU和在系統(tǒng)可編程 Flash，使得 AT89C52為眾多嵌入式控制應(yīng)用系統(tǒng)提供高靈活、超有效的解決方案 。 AT89C52具有以下標(biāo)準(zhǔn)功能： 8k字節(jié) Flash， 256字節(jié) RAM， 32位 I/O口線，看門狗定時(shí)器， 2個(gè)數(shù)據(jù)指針，三個(gè) 16位定時(shí)/計(jì)數(shù)器，一個(gè) 6向量 2級(jí)中 斷結(jié)構(gòu)，全雙工串行口，片內(nèi)晶振及時(shí)鐘電路。另外， AT89C52可 5 降至 0Hz靜態(tài)邏輯操作，支持 2種軟件可選擇節(jié)電模式?？臻e模式下， CPU停止工作，允許 RAM、定時(shí) /計(jì)數(shù)器、串口、中斷繼續(xù)工作。掉電保護(hù)方式下， RAM內(nèi)容被保存，振蕩器被凍結(jié)，單片機(jī)一切工作停止，知道下一個(gè)中斷或硬件復(fù)位為止。 8位微控制器、 8K字節(jié)在系統(tǒng)可編程。 AT89C52有 40個(gè)引腳， 32個(gè)外部雙向輸入 /輸出（ I/O）端口，同時(shí)內(nèi)含 2個(gè)外中端口， 3個(gè) 16位可編程定時(shí)計(jì)數(shù)器， 2個(gè)全雙工串行通信口， 2個(gè)讀寫口線， AT89C52可以按照常規(guī)方法進(jìn) 行編程，也可以在線編程。其將通用的微處理器和 Flash存儲(chǔ)器結(jié)合在一起，特別是可反復(fù)擦寫的 Flash存儲(chǔ)器可有效的降低開(kāi)發(fā)成本。 6 MCU 1 The definition of MCU MCU is an integrated on a single chip a plete puter though most of his features in a small chip,but it has a need to plete the majority of puter ponents:CPU,memory,internal and external bus system,most w ill have the the same time,such as integrated c ommunication interfaces,times,realtime Clock and other peripheral now the most powerful MCU mic roco mputer system c an even voic e,image,working,input and output c omplex system integration on a single c hip. Also know n as singlechip MCU(Microcontroller),bec ause it w as first used in the field of industrial c by the singlec hip CPU chip developed from the dedicated proc design concept is the first by a large number of peripherals and CPU in a single chip,the puter system so that smaller,more easily integrated into the plex and demanding on the volume control the Z80 is one of the first design in accordanc e w ith the idea of the proc essor,From then on,the MCU and the development of a dedic ated processor parted w ays. Early MCU 8bit or all of the four. One of the most succ essful is the INTEL 8031, bec ause the performance of a simple and reliable access to a lot of good praise. Then developed in 8031 out of MCS51 MCU Systems. SCM systems based on this system until now is still w idely used. With the increased requirements of industrial control field, began a 16 bit microcontroller, because the cost is not satisfactory but have not been very w idely used. After 90 years w ith the great development of consumer electronics, microcontroller technology has been a huge increase. With INTEL i960 series, espec ially the later series of w idely used ARM, 32bit microc ontroller quickly replac e highend 16bit MCU status and enter the mainstream market. The traditional 8bit microc ontroller performanc e have been the rapid increase capac ity increase pared to 80 the number of times. Currently, highend 32bit microcontroller c loc ked over 300MHz, the performanc e catching the mid9039。s dedic ated processor, w hile the average model pric es fall to one . dollars, the most highend [1] model only 10 dollars. Modern SCM systems are no longer only in the development and use of bare metal environment, a large number of proprietary embedded operating system is w idely used in the full range of SCM. The handheld puters and cell phones as the c ore processing of highend microcontroller can even use a dedic ated Windows and Linux operating systems. More than a dedic ated MCU processor suitable for embedded systems, so it w as up to the applic ation. In fact the number of SCM is the world39。s largest puter. Modern human life used in almost every piec e of electronic and mechanic al products w ill be integrated single chip. Phone, telephone, c alculator, home applianc es, elec tronic toys, handheld puters and puter accessories such as a mouse w ith a 12 in both the Department of SCM. Personal puter w ill have a large number of SCM in the work. General c ar w ith more than 40 SCM, plex industrial con