【正文】 digit year followed by a twodigit week code, such that a part bearing the code 8341 was manufactured in week 41 of 1983, or approximately in October 1983. Structure and function of the MCS51 series Structure and function of the MCS51 series onechip puter is a name of a piece of onechip puter series which Intel Company produces. This pany introduced 8 topgrade onechip puters of MCS51 series in 1980 after introducing 8 onechip puters of MCS48 series in 1976. It belong to a lot of kinds this line of onechip puter the chips have,such as 8051, 8031, 8751, 80C51BH, 80C31BH,etc., their basic position, basic performance and instruction system are all the same. 8051 daily representatives 51 serial onechip puters . An onechip puter system is made up of several following parts: ( 1) One microprocessor of 8 (CPU). ( 2) At slice data memory RAM (128B/256B),it use not depositting not can reading /data that write, such as result not middle of operation, final result and data wanted to show, etc. ( 3) Procedure memory ROM/EPROM (4KB/8KB ), is used to preserve the procedure , some initial data and form in slice. But does not take ROM/EPROM within some onechip puters, such as 8031 , 8032, 80C ,etc.. ( 4) Four 8 run side by side I/O interface P0 four P3, each mouth can use as introduction , may use as exporting too. ( 5) Two timer / counter, each timer / counter may set up and count in the way, used to count to the external incident, can set up into a timing way too, and can according to count or result of timing realize the control of the puter. ( 6) Five cut off cutting off the control system of the source . ( 7) One all duplexing serial I/O mouth of UART (universal asynchronous receiver/transmitter (UART) ), is it realize onechip puter or onechip puter and serial 第 頁 共 頁 munication of puter to use for. ( 8) Stretch oscillator and clock produce circuit, quartz crystal finely tune electric capacity need outer. Allow oscillation frequency as 12 megahertas now at most. Every the abovementioned part was joined through the inside data bus .Among them, CPU is a core of the onechip puter, it is the control of the puter and mand centre, made up of such parts as arithmetic unit and controller , etc.. The arithmetic unit can carry on 8 persons of arithmetic operation and unit ALU of logic operation while including one, the 1 storing device temporarilies of 8, storing device 2 temporarily, 839。 20 世紀(jì)中期半導(dǎo)體制造技術(shù)的進(jìn)步，使得集成電路成為可能。成本低是由于芯片把所有的元件通過照相平版技術(shù)，作為一個單位印刷，而不是在一個時間只制作一個晶體管。每 mm178。雖然單獨設(shè)計開發(fā)一個復(fù)雜的集成電路的成本非常高，但當(dāng)分散到數(shù)以百萬計的產(chǎn)品上，每個 IC 的成本就很小了。由摩爾定律的現(xiàn)代釋義可知，集成電路中的晶體管數(shù)量，每兩年增加一倍。由于用戶對 IC的運行速度和功率消耗非常敏感，各生產(chǎn)商在如何開發(fā)運用更好的技術(shù)上存在著激烈的競爭?，F(xiàn)代計算，通信，制造和交通系統(tǒng)，包括互聯(lián)網(wǎng)，全 都依賴于集成電路的存在。 這些數(shù)字 IC, 以微處理器，數(shù)字信號處理器（ DSP）和微控制器為代表，工作中使用二進(jìn)制，處理 1 和 0 信號。 19 世紀(jì) 30 年代始，研究者如貝爾實驗室的 William Shockley 通過研究，認(rèn)為在化學(xué)元素周期表中的半導(dǎo)體硅元素是構(gòu)成固態(tài)真空管最可能的原料。 半導(dǎo)體 IC 是逐層制造的，其構(gòu)造工藝過程包括以下關(guān)鍵步驟：成像 ， 沉積 ， 蝕刻 ， 在其構(gòu)造過程輔以摻雜及清潔。 在制造一個自排列 CMOS 的過程中，門層（多晶硅或金屬）穿過擴(kuò)散層形成晶體管 。其層的制作過程非常象照相過程，雖然可見光譜中的光波不能用來曝光元件層，因為他們太大了。商用電路封裝很快就發(fā)展到雙列直插式封裝（ dual inline package DIP） ,開始是陶瓷，之后是塑料。以 SmallOutline Integrated Circuit（ SOIC）為例，貼片式占用面積比 DIP 少 30－ 50％，厚度少 70％。 球柵陣列（ BGA）封裝出現(xiàn)于 20 世紀(jì) 70 年代。 芯片制造日期通常表示為兩位數(shù)的年份加兩位數(shù)字的星期代碼。 諸如此類的單芯片電腦有很多種 ，如 8051，8031， 8751， 80C51BH， 80C31BH 等，其基本組成，基本性能和指令系統(tǒng)都是相同的。但一些單芯片電腦沒有考慮 ROM / EPROM，如 8031， 8032， 80C51等等。 （ 8）振蕩器和時鐘產(chǎn)生電路， 需要考慮 石英晶體微調(diào)能力。此外，協(xié)調(diào)往往是作為對8051 內(nèi)的數(shù)據(jù)傳輸轉(zhuǎn)運站 考慮 。這是一個字節(jié)的地址，其實程序計數(shù)器， 第 頁 共 頁