機(jī)電專業(yè)英語第2版19unit 19

1、LOGO單單 片片 機(jī)機(jī) 介介 紹紹 徐存善主編 徐存善主編 徐存善主編 Microcontrollers are hidden inside a surprising number of products these days (Fig.19.1). About 55% of all CPUs sold in the world are 8-bit microcontrollers. If your microwave oven has an LED or LCD screen and a keypad, it contains a microcontroller. All modem au

2、tomobiles contain at least one microcontroller, and can have as many as six or seven: The engine is controlled by a microcontroller, as are the anti-lock brakes and so on 1 . Any device that has a remote control almost certainly contains a microcontroller: TVs, VCRs and high-end stereo systems all f

3、all into this category 2 . Digital cameras, cell phones, camcorders, answering machines, laser printers, telephones (the ones with caller ID, 20-number memory, etc.), pagers, and refrigerators, dishwashers, washers and dryers (the ones with displays and keypads) You get the idea. Basically, any prod

4、uct or device that interacts with its user has a microcontroller buried inside 3 . 徐存善主編Fig.19-1 Products containing a microcontroller 徐存善主編 What is Microcontroller A microcontroller (also MCU or C) is a computer system-on-a-chip, containing a processor, memory, and input/output functions. It is a m

5、icroprocessor emphasizing high integration, in contrast to a general-purpose microprocessor (the kind used in a PC) 4 . In addition to the usual arithmetic and logic elements of a general purpose microprocessor, the microcontroller integrates additional elements such as read-write memory for data st

6、orage, read-only memory for program storage, EEPROM for permanent data storage, peripheral devices, and input/output interfaces. At clock speeds of as little as a few MHz or even lower, microcontrollers often operate at very low speed compared to modern day microprocessors, but this is adequate for

7、typical applications. They consume relatively little power (milliwatts), and will generally have the ability to sleep while waiting for a peripheral event such as a button press to wake them up again to do something. Power consumption while sleeping may be just nanowatts, making them ideal for low p

8、ower and long lasting battery applications 5 . 徐存善主編Intel 8051The Intel 8051 is a Harvard architecture, single chip microcontroller (C) which was developed by Intel in 1980 for use in embedded systems.Intels original 8051 family was developed using NMOS technology, but later versions, identified by

9、a letter “C” in their name, e.g. 80C51, used CMOS technology and were less power-hungry than their NMOS predecessors 6 - this made them eminently more suitable for battery-powered devices. 徐存善主編The 8051 families have following important features (Fig.19.2):(1) 8-bit data bus - It can access 8 bits o

10、f data in one operation (hence it is an 8-bit microcontroller).(2) 16-bit address bus - It can access 216 memory locations - 64KB each of RAM and ROM.(3) On-chip RAM - 128 bytes (“Data Memory”).(4) On-chip ROM - 4KB (“Program Memory”).(5) Four byte bi-directional inputoutput port. (6) UART (serial p

11、ort).(7) Two 16-bit Counter/timers.(8) Two-level interrupt priority.(9) Power saving mode. 徐存善主編Fig.19-2 Important features in 8501 families 徐存善主編 A particularly useful feature of the 8051 core is the inclusion of a Boolean processing engine which allows bit-level Boolean logic operations to be carr

12、ied out directly and efficiently on internal registers and RAM. This feature helped to cement the 805ls popularity in industrial control applications. Another valued feature is that it has four separate register sets, which can be used to greatly reduce interrupt latency compared to the more common

13、method of storing interrupt context on a stack. The original 8051 core ran at 12 clock cycles per machine cycle, with most instructions executing in one or two machine cycles. With a 12 MHz clock frequency, the 8051 could thus execute 1 million one-cycle instructions per second or 500 000 two-cycle

14、instructions per second. Enhanced 8051 cores are now commonly used which run at six, four, two, or even one clock per machine cycle, and have clock frequencies of up to 100 MHz, and are thus capable of an even greater number of instructions per second. 徐存善主編 Common features included in modern 8051 b

15、ased microcontroller includebuilt-in reset timers with brown-out detection, on-chip oscillators, self programmable Flash ROM program memory, boot loader code in ROM, EEPROM non-volatile data storage, IC, SPI, and USB host interfaces, PWMgenerators, analog comparators, A/D and D/A converters, extra c

16、ounters andtimers, in-circuit debugging facilities, more interrupt sources,and extra powersaving modes. 徐存善主編microcontroller ,maikrukntrul n. 微控制器，微控器，單片機(jī)camcorder kmk:d n. 攝錄像機(jī)；便攜式攝像機(jī)display ,displei n. 顯示器，指示器；陳列，展覽vt. 展示；顯示integration ,intirein n. 集成；綜合；集中arithmetic rimtik n. 算術(shù)，算法；運(yùn)算permanent p:

17、mnnt adj. 永久的，永恒的；不變的peripheral prifrl adj. 外圍的；外設(shè)的；次要的n. 外圍設(shè)備eminently eminntli adv. 突出地；顯著地access kses vt. 使用；存取，訪問；接近 n. 進(jìn)入；使用權(quán) 徐存善主編cement siment vt. 鞏固，加強(qiáng)；(用水泥等)粘合 n. 水泥l(xiāng)atency leitnsi n. 等待時(shí)間，延遲，潛伏期stack stk n. 堆；堆疊；存儲棧，堆棧non-volatile nn,vltail adj. 非易失的；不揮發(fā)的debug di:b vt. 調(diào)試；排除故障 n. 調(diào)試器，排錯器fa

18、ll into 落入；分成，歸入，屬于；開始（某事）interacts with 與相互影響或作用in contrast to 與對比(或?qū)φ?；與相反 徐存善主編 1. The engine is controlled by a microcontroller, as are the anti-lock brakes and so on. 譯文：發(fā)動機(jī)、防抱死制動系統(tǒng)等等都是用單片機(jī)控制的。 說明：句中anti-lock brake 表示防抱死制動系統(tǒng)或防鎖死煞車系統(tǒng)，可安裝在任何帶液壓剎車的汽車上，能避免在緊急剎車時(shí)方向失控及車輪側(cè)滑?！癮s” is a substitute for a

19、clause，and it can be replaced by “so” (也一樣)，e.g. 1) She is a doctor, as/so is her husband. 她和她丈夫都是醫(yī)生。 2) Business confidence has picked up, as/so has the Paris Bourse. 商業(yè)信心有所提升，巴黎證券交易所的交易情況也有好轉(zhuǎn)。Language points 徐存善主編 2. Any device that has a remote control almost certainly contains a microcontroller:

20、 TVs, VCRs and high-end stereo systems all fall into this category. 譯文：任何具有遠(yuǎn)程遙控的設(shè)備都幾乎肯定包含一部單片機(jī)：電視機(jī)、錄像機(jī)、高端立體聲音響系統(tǒng)都屬于這一類。 說明：“that” is a relative pronoun used to introduce an attributive clause modifying “device”. “fall into” means “be included in or classified as, belong to” (歸入，屬于，分成；陷入), e.g. 1) Go

21、ing forward, these cases will fall into five distinct categories. 接下來，這些案件將被歸入五大類別。 2) Old civilization may fall into decay. 古老的文化可能會漸漸衰落下去。Language points 徐存善主編 3. Basically, any product or device that interacts with its userhas a microcontroller buried inside. 譯文：任何與用戶進(jìn)行互動的產(chǎn)品或設(shè)備內(nèi)部都嵌有單片機(jī)。 說明：“that”

22、 is a relative pronoun used to introduce anattributive clause. “buried inside” is a past participle phrasemodifying “microcontroller”. “interact with” means “act togetherwith others” (與互動或相互作用), e.g. But because these particles are electrically charged, they alsointeract with the Earths magnetic fie

23、ld. 但是因?yàn)檫@些粒子是帶電的，所以它們會受地球磁場的影響。Language points 徐存善主編 4. It is a microprocessor emphasizing high integration, in contrast to ageneral-purpose microprocessor (the kind used in a PC). 譯文：與應(yīng)用在個(gè)人電腦中的通用型微處理器相比，它是高度集成的微處理器。 說明: “emphasizing high integration” is a present participle phrase used asan attribu

24、te modifying “microprocessor”. “in contrast to” means “與對比(或?qū)φ?；與相反” 1) The gaiety and lightness of his work were in contrast to his own sad nature. 他的作品的歡樂與輕快與他哀傷的性格形成鮮明的對照。 2) In contrast to her elder brother, she was always considerate in her treatment of others. 和她哥哥完全不一樣，她對別人總是很體貼。Language poin

25、ts 徐存善主編5. Power consumption while sleeping may be just nanowatts, making them ideal for low power and long lasting battery applications.譯文：睡眠時(shí)消耗功率可能只有納瓦級(109 W)，所以很適宜應(yīng)用在低功耗且長期用電池供電的場合。說明：句中連詞while表示“當(dāng)?shù)臅r(shí)候”?，F(xiàn)在分詞sleeping作時(shí)間狀語，相當(dāng)于一個(gè)時(shí)間狀語從句。making them ideal for low power and long lasting battery applica

26、tions是現(xiàn)在分詞短語，作結(jié)果狀語。be ideal for表示“對很理想，適用于” e.g.1) The cable system is ideal for spanning natural barriers of wide rivers, deep valleys, or ravines.這種鋼索體系是跨越寬河道、深丘谷或深山谷天然障礙物的理想體系。2) Unlike incandescent or fluorescent lamps, which spew light in all directions, LEDs generate directional light, making

27、them ideal for selectively illuminating areas. 不像白熾燈或者熒光燈那樣燈光四射，LED產(chǎn)生的是定向光，定點(diǎn)照明的理想之選。 Language points 徐存善主編 6. Intels original 8051 family was developed using NMOS technology, but laterversions, identified by a letter “C” in their name, e.g. 80C51, used CMOS technologyand were less power-hungry than

28、 their NMOS predecessors. 譯文：英特爾最早的805l系列是用NMOS技術(shù)開發(fā)的，但后來的標(biāo)以“C”字母如80C51的版本是用CMOS技術(shù)開發(fā)的芯片。 說明：句中現(xiàn)在分詞短語using NMOS technology作方式狀語。過去分詞短語identified by a letter “C” in their name作定語修飾later versions，相當(dāng)于一個(gè)定語從句。power-hungry表示“高耗電的” e.g. The new lines will be used to carry electricity from coal-rich inland pr

29、ovinces to the power-hungry coast. 新輸電線路將用于連接中國煤炭資源豐富的內(nèi)陸省份和電力短缺的沿海地區(qū)。 Language points 徐存善主編 I. Answer the following questions.1. How many kinds of products or devices embedded with a microcontroller are listed in the first paragraph? What are they？2. What is referred to as a microcontroller? Sixteen

30、 kinds of products or devices are listed. They are microwave ovens, modem automobiles, TVs, VCRs, high-end stereo systems, digital cameras, cell phones, camcorders, answering machines, laser printers, telephones (the ones with caller ID, 20-number memory, etc.), pagers, and refrigerators, dishwasher

31、s, washers and dryers (the ones with displays and keypads).A microcontroller is a computer system-on-a-chip, containing a processor, memory, and input/output functions.Exercises 徐存善主編 I. Answer the following questions.3. What are the major differences between the microcontroller and the general-purp

32、ose microprocessor used in a PC?4. What are the two particularly useful features of the 8051 core? In contrast to a general-purpose microprocessor, the microcontroller integrates additional elements such as read-write memory for data storage, read-only memory for program storage, EEPROM for permanen

33、t data storage, peripheral devices, and input/output interfaces.The two particularly useful features of the 8051 core are the inclusion of a Boolean processing engine and four separate register sets.Exercises 徐存善主編II. Mark the following statements with T (true) or F (false) according to the text.1.

34、The majority of microcontrollers in use today are embedded in other machinery, which are called embedded systems.2. The high integration of the microcontroller drastically reduces the number of chips and the amount of wiring and circuit board space.3. By reducing the size and cost compared to a desi

35、gn that uses separate elements, microcontrollers make it economical to digitally control even more devices and processes.TTTExercises 徐存善主編II. Mark the following statements with T (true) or F (false) according to the text.4. Microcontrollers operate at very low speed, so their applications are very

36、limited.5. The Intel 80C51 family consumes less power than the original 8051 family.6. Because the 8051 core contains four separate register sets, it is widely used in industrial control.FTFExercises 徐存善主編1.防抱死制動系統(tǒng) 2.可儲存數(shù)據(jù)的讀寫存儲器 3.通用微處理機(jī) 4.兩級中斷優(yōu)先權(quán) III. Translate the following phrases and sentences i

37、nto English. anti-lock brakes read-write memory for data storage general-purpose microprocessor two-level interrupt priorityExercises 徐存善主編 III. Translate the following phrases and sentences into English.5. 微控制器是指一個(gè)集成在一塊芯片上的計(jì)算機(jī)系統(tǒng)，它有 處理器、存儲器和輸入輸出功能。A microcontroller is a computer system-on-a-chip, co

38、ntaining a processor，memory, and input/output functions. 徐存善主編 1結(jié)合具體語言環(huán)境了解全句大意。 2剖析全句，分清主要成分和次要成分，主句和從句。 3緊縮主干，確定句子的主、謂語，找出句子的基本構(gòu)架，及其所屬句型。 4疏通脈絡(luò)，清理枝蔓，分清主次關(guān)系，注意上下層次，前后引襯及其邏輯關(guān)系。 5按漢語造句的規(guī)律，進(jìn)行選詞和語序的調(diào)整。 6反復(fù)研究譯文，進(jìn)行詞句錘煉的潤飾工夫，最后定稿。 Sample: For a family of four, for example, it is more convenient as well as

39、cheaper to sit comfortably at home, with almost unlimited entertainment available, than to go out in search of amusement elsewhere 分析：該句的骨干結(jié)構(gòu)為“it is moreto do sth than to do sth else”是一個(gè)比較結(jié)構(gòu)，而且是在兩個(gè)不定式之間進(jìn)行比較；該句中共有三個(gè)謂語結(jié)構(gòu)，它們之間的關(guān)系為：it is more convenient as well as cheaper to為主體結(jié)構(gòu)，但it是形式主語，真正的主語為第二個(gè)謂語結(jié)構(gòu)：

40、to sit comfortably at home，并與第三個(gè)謂語結(jié)構(gòu)to go out in search of amusement elsewhere作比較。 綜合上述翻譯方法，這個(gè)句子我們可以翻譯為：譬如，對于一個(gè)四口之家來說，舒舒服服地在家中看電視，就能看到幾乎數(shù)不清的娛樂節(jié)目，這比到外面別的地方去消遣又便宜又方便。 徐存善主編1順譯法順譯法 順譯法就是按照原文時(shí)間、方位、邏輯等順序?qū)㈤L句的內(nèi)容再現(xiàn)，例如： Even when we turn off the beside lamp and are fast asleep, electricity is working for us,

41、 driving our refrigerators, heating our water, or keeping our rooms air-conditioned. 分析：該句子由一個(gè)主句、三個(gè)作伴隨狀語的現(xiàn)在分詞以及位于句首的時(shí)間狀語從旬組成，共有五層意思：A即使在我們關(guān)掉了床頭燈深深地進(jìn)入夢鄉(xiāng)時(shí)；B電仍在為我們工作；C幫我們開動電冰箱；D加熱水；E或是室內(nèi)空調(diào)機(jī)繼續(xù)運(yùn)轉(zhuǎn)。上述五層意思的邏輯關(guān)系以及表達(dá)的順序與漢語完全一致，因此，我們可以通過順序法，譯為： 即使在我們關(guān)掉了床頭燈深深地進(jìn)入夢鄉(xiāng)時(shí)，電仍在為我們工作；幫我們開動電冰加熱，或使室內(nèi)空調(diào)機(jī)繼續(xù)運(yùn)轉(zhuǎn)。 徐存善主編2倒譯法倒譯法 在

42、翻譯有些長句時(shí)，要想使譯文通順、符合漢語表達(dá)習(xí)慣，翻譯時(shí)必須從后往前譯，這就是倒譯法。譬如： It therefore becomes more and more important that, if students are not to waste their opportunities, there will have to be much more detailed information about courses and more advice. 因此，如果要使學(xué)生充分利用他們（上大學(xué)）的機(jī)會，就得為他們提供大量關(guān)于課程的更為詳盡的信息，作更多的指導(dǎo)。這個(gè)問題顯得越來越重要。 徐存

43、善主編3分譯法分譯法 分譯法是將長句拆開來，將其中從句或短語譯成短句，分開來敘述，如: Television, it is often said, keeps one informed about current events, allows one to follow the latest developments in science and politics, and offers an endless series of programs which are both instructive and entertaining. 分析：在此長句中，有一個(gè)插入語“it is often s

44、aid”，三個(gè)并列的謂語結(jié)構(gòu)，還有一個(gè)定語從句，這三個(gè)并列的謂語結(jié)構(gòu)盡管在結(jié)構(gòu)上同屬于同一個(gè)句子，但都有獨(dú)立的意義，因此在翻譯時(shí)，可以采用分句法，按照漢語的習(xí)慣把整個(gè)句子分解成幾個(gè)獨(dú)立的分句，此句可譯為：人們常說，通過電視可以了解時(shí)事，掌握科學(xué)和政治的最新動態(tài)。從電視里還可以看到層出不窮、既有教育意義又有娛樂性的新節(jié)目。 徐存善主編4綜合法綜合法 要求我們把各種方法綜合使用，先仔細(xì)分析，或按照時(shí)間的先后，或按照邏輯順序，順逆結(jié)合，主次分明地對全句進(jìn)行綜合處理，以便把英語原文翻譯成通順的漢語句子。例如： People were afraid to leave their houses, for

45、although the police had been ordered to stand by in case of emergency, they were just as confused and helpless as anybody else. 盡管警察已接到命令，要作好準(zhǔn)備以應(yīng)付緊急情況，但人們不敢出門，因?yàn)榫煲埠推渌艘粯硬恢牒蜔o能為力。力。 徐存善主編An assembler is a software tool designed to simplify the task of writing computer programs.1 It translates symbo

46、lic code into executable object code. This object code may then be programmed into a microcontroller and executed. Assembly language programs translate directly into CPU instructions which instruct the processor what operations to perform. Therefore, to effectively write assembly programs, you shoul

47、d be familiar with both the microcomputer architecture and the assembly language.匯編程序是什么？匯編程序是什么？ 匯編程序是一種用來簡化計(jì)算機(jī)編寫程序的軟件工具。匯編程序把符號化的代碼（匯編指令）編譯成可執(zhí)行的目標(biāo)代碼（機(jī)器指令），然后把該目標(biāo)代碼編入單片機(jī)（的程序存儲器）中并加以執(zhí)行。匯編語言程序可直接譯成CPU指令，命令處理器完成相應(yīng)的運(yùn)算。所以，要有效地編寫匯編語言程序，就需要對微型計(jì)算機(jī)的結(jié)構(gòu)和匯編語言都很熟悉。 徐存善主編 Assembly language operation codes are ea

48、sily remembered (MOV for moveinstructions, ADD for addition, and so on). You can also symbolically expressaddresses and values referenced in the operand field of instructions. Since you assign these names, you can make them as meaningful as themnemonics for the instructions. For example, if your pro

49、gram must manipulatea date as data, you can assign it the symbolic name DATE. If your programcontains a set of instructions used as a timing loop (a set of instructions executedrepeatedly until a specific amount of time has passed), you can name theinstruction group TIMERLOOP. 匯編語言操作代碼很容易記（MOV就是移動指令

50、，ADD就是加法指令等等。還可以用符號表示（存儲器）地址和指令的操作字段值。 因?yàn)橹付诉@些名字，指令就有了意義，比較容易記憶。比如，如果你在程序中要多次用到一個(gè)日期作為數(shù)據(jù)，你可以給這個(gè)日期指定一個(gè)符號化的名字DATE（日期）。如果你程序中含有用作延時(shí)循環(huán)的一組指令 (在指定的時(shí)間內(nèi)反復(fù)執(zhí)行的一組指令)，你可以給這段指令起名TIMERLOOP。 徐存善主編An assembly program has three constituent parts:(1) Machine instructions.(2) Assembler directives.(3) Assembler controls

51、.A machine instruction is a machine code that can be executed by the machine. Detailed discussion of the machine instructions can be found in the hardware manuals of the 8051 family or other microcontrollers.Assembler directives are used to define the program structure and symbols, and generate non-

52、executable code (data, messages, etc.).Assembler controls set the assembly modes and direct the assembly flow. 匯編程序有3個(gè)組成要素：（1）機(jī)器指令。（2）匯編指令。（3）匯編控制。 機(jī)器指令就是可以由CPU執(zhí)行的機(jī)器代碼。對機(jī)器指令的詳細(xì)討論可以參看8051系列或其他單片機(jī)的硬件手冊。 匯編指令用于定義程序的結(jié)構(gòu)和符號，生成非執(zhí)行代碼（數(shù)據(jù)、信息等）。 匯編控制設(shè)置匯編程序的模式和流向。 徐存善主編assembler sembl n. 匯編程序；匯編機(jī)；裝配工simplify si

53、mplifai vt. 簡化；使單純；使簡易symbolic simblik adj. 象征的；符號的executable eksikju:tbl adj. 可執(zhí)行的；可實(shí)行的instruct instrkt vt. 指導(dǎo)；通知；命令；教授architecture :kitekt n. 建筑學(xué)；建筑風(fēng)格；計(jì)算機(jī)構(gòu)造，架構(gòu)assembly sembli n. 裝配；集會；匯編，編譯symbolically simblikli adv. 象征性地；用符號表示operand prnd n. 操作數(shù)；運(yùn)算對象mnemonics ni:mniks n. 記憶術(shù)manipulate mnipjuleit

54、vt. 操縱；操作；巧妙地處理New words and phrasesExercises 徐存善主編 I. Answer the following questions.1. What is an assembler?2. What areas of knowledge should a person understand in order to effectively write assembly programs? An assembler is a software tool designed to simplify the task of writing computer progr

55、ams.To effectively write assembly programs, a person should understand both the microcomputer architecture and the assembly language.Exercises 徐存善主編 I. Answer the following questions.3. What are the three constituent parts of an assembly program?4. Where can we find detailed discussion of the machine instructions?An