外文文献及翻译-单片机

单片机

1 单片机定义

单片机是指一个集成在一块芯片上的完整计算机系统。尽管它的大部分功能集成在一块小芯片上，但是它具有一个完整计算机所需要的大部分部件：CPU、内存、内部和外部总线系统，目前大部分还会具有外存。同时集成诸如通讯接口、定时器，实时时钟等外围设备。而现在最强大的单片机系统甚至可以将声音、图像、网络、复杂的输入输出系统集成在一块芯片上。

单片机也被称为微控制器（Microcontroller Unit），常用英文字母的缩写MCU表示单片机，它最早是被用在工业控制领域。单片机由芯片内仅有CPU的专用处理器发展而来。最早的设计理念是通过将大量外围设备和CPU集成在一个芯片中，使计算机系统更小，更容易集成进复杂的而对体积要求严格的控制设备当中。INTEL的Z80是最早按照这种思想设计出的处理器，从此以后，单片机和专用处理器的发展便分道扬镳。

早期的单片机都是8位或4位的。其中最成功的是INTEL的8031，因为简单可靠而性能不错获得了很大的好评。此后在8031上发展出了MCS51系列单片机系统。基于这一系统的单片机系统直到现在还在广泛使用。随着工业控制领域要求的提高，开始出现了16位单片机，但因为性价比不理想并未得到很广泛的应用。90年代后随着消费电子产品大发展，单片机技术得到了巨大提高。随着INTEL i960系列特别是后来的ARM系列的广泛应用，32位单片机迅速取代16位单片机的高端地位，并且进入主流市场。而传统的8位单片机的性能也得到了飞速提高，处理能力比起80年代提高了数百倍。目前，高端的32位单片机主频已经超过300MHz，性能直追90年代中期的专用处理器，而普通的型号出厂价格跌落至1美元，最高端的型号也只有10美元。当代单片机系统已经不再只在裸机环境下开发和使用，大量专用的嵌入式操作系统被广泛应用在全系列的单片机上。而在作为掌上电脑和手机核心处理的高端单片机甚至可以直接使用专用的Windows和Linux操作系统。

单片机比专用处理器更适合应用于嵌入式系统，因此它得到了最多的应用。事实上单片机是世界上数量最多的计算机。现代人类生活中所用的几乎每件电子和机械产品中都会集成有单片机。手机、电话、计算器、家用电器、电子玩具、掌上电脑以及鼠标等电脑配件中都配有1-2部单片机。而个人电脑中也会有为数不少的单片机在工作。汽车上一般配备40多部单片机，复杂的工业控制系统上甚至可能有数百台单片机在同时工作！单片机的数量不仅远超过PC机和其他计算的总和，甚至比人类的数量还要多。

2 单片机介绍

单片机又称单片微控制器,它不是完成某一个逻辑功能的芯片,而是把一个计算机系统集成到一个芯片上。相当于一个微型的计算机，和计算机相比，单片机只缺少了I/O设备。概括的讲：一块芯片就成了一台计算机。它的体积小、质量轻、价格便宜、为学习、应用和开发提供了便利条件。同时，学习使用单片机是了解计算机原理与结构的最佳选择。

单片机内部也用和电脑功能类似的模块，比如CPU，内存，并行总线，还有和硬盘作用相同的存储器件，不同的是它的这些部件性能都相对我们的家用电脑弱很多，不过价钱也是低的，一般不超过10元即可......用它来做一些控制电器一类不是很复杂的工作足矣了。我

们现在用的全自动滚筒洗衣机、排烟罩、VCD等等的家电里面都可以看到它的身影！......它主要是作为控制部分的核心部件。

它是一种在线式实时控制计算机，在线式就是现场控制，需要的是有较强的抗干扰能力，较低的成本，这也是和离线式计算机的（比如家用PC）的主要区别。

单片机是靠程序运行的，并且可以修改。通过不同的程序实现不同的功能，尤其是特殊的独特的一些功能，这是别的器件需要费很大力气才能做到的，有些则是花大力气也很难做到的。一个不是很复杂的功能要是用美国50年代开发的74系列，或者60年代的CD4000系列这些纯硬件来搞定的话，电路一定是一块大PCB板！但是如果要是用美国70年代成功投放市场的系列单片机，结果就会有天壤之别！只因为单片机的通过你编写的程序可以实现高智能，高效率，以及高可靠性！

由于单片机对成本是敏感的，所以目前占统治地位的软件还是最低级汇编语言，它是除了二进制机器码以上最低级的语言了，既然这么低级为什么还要用呢？很多高级的语言已经达到了可视化编程的水平为什么不用呢？原因很简单，就是单片机没有家用计算机那样的CPU，也没有像硬盘那样的海量存储设备。一个可视化高级语言编写的小程序里面即使只有一个按钮，也会达到几十K的尺寸！对于家用PC的硬盘来讲没什么，可是对于单片机来讲是不能接受的。单片机在硬件资源方面的利用率必须很高才行，所以汇编虽然原始却还是在大量使用。一样的道理，如果把巨型计算机上的操作系统和应用软件拿到家用PC上来运行，家用PC的也是承受不了的。

可以说，二十世纪跨越了三个“电”的时代，即电气时代、电子时代和现已进入的电脑时代。不过，这种电脑，通常是指个人计算机，简称PC机。它由主机、键盘、显示器等组成。还有一类计算机，大多数人却不怎么熟悉。这种计算机就是把智能赋予各种机械的单片机（亦称微控制器）。顾名思义，这种计算机的最小系统只用了一片集成电路，即可进行简单运算和控制。因为它体积小，通常都藏在被控机械的“肚子”里。它在整个装置中，起着有如人类头脑的作用，它出了毛病，整个装置就瘫痪了。现在，这种单片机的使用领域已十分广泛，如智能仪表、实时工控、通讯设备、导航系统、家用电器等。各种产品一旦用上了单片机，就能起到使产品升级换代的功效，常在产品名称前冠以形容词——“智能型”，如智能型洗衣机等。现在有些工厂的技术人员或其它业余电子开发者搞出来的某些产品，不是电路太复杂，就是功能太简单且极易被仿制。究其原因，可能就卡在产品未使用单片机或其它可编程逻辑器件上。

3 单片机历史

单片机诞生于20世纪70年代末，经历了SCM、MCU、SOC三大阶段。

（1）SCM即单片微型计算机（Single Chip Microcomputer）阶段，主要是寻求最佳的单片形态嵌入式系统的最佳体系结构。“创新模式”获得成功，奠定了SCM与通用计算机完全不同的发展道路。在开创嵌入式系统独立发展道路上，Intel公司功不可没。

（2）MCU即微控制器（Micro Controller Unit）阶段，主要的技术发展方向是：不断扩展满足嵌入式应用时，对象系统要求的各种外围电路与接口电路，突显其对象的智能化控制能力。它所涉及的领域都与对象系统相关，因此，发展MCU的重任不可避免地落在电气、电子

技术厂家。从这一角度来看，Intel逐渐淡出MCU的发展也有其客观因素。在发展MCU方面，最著名的厂家当数Philips公司。

Philips公司以其在嵌入式应用方面的巨大优势，将MCS-51从单片微型计算机迅速发展到微控制器。因此，当我们回顾嵌入式系统发展道路时，不要忘记Intel和Philips的历史功绩。

（3）嵌入式系统阶段，单片机是嵌入式系统的独立发展之路，向MCU阶段发展的重要因素，就是寻求应用系统在芯片上的最大化解决；因此，专用单片机的发展自然形成了SOC化趋势。随着微电子技术、IC设计、EDA工具的发展，基于SOC的单片机应用系统设计会有较大的发展。因此，对单片机的理解可以从单片微型计算机、单片微控制器延伸到单片应用系统。

4 单片机的应用领域

目前单片机渗透到我们生活的各个领域，几乎很难找到哪个领域没有单片机的踪迹。导弹的导航装置，飞机上各种仪表的控制，计算机的网络通讯与数据传输，工业自动化过程的实时控制和数据处理，广泛使用的各种智能IC卡，民用豪华轿车的安全保障系统，录像机、摄像机、全自动洗衣机的控制，以及程控玩具、电子宠物等等，这些都离不开单片机。更不用说自动控制领域的机器人、智能仪表、医疗器械了。因此，单片机的学习、开发与应用将造就一批计算机应用与智能化控制的科学家、工程师。

单片机广泛应用于仪器仪表、家用电器、医用设备、航空航天、专用设备的智能化管理及过程控制等领域，大致可分如下几个范畴：

（1）在智能仪器仪表上的应用

单片机具有体积小、功耗低、控制功能强、扩展灵活、微型化和使用方便等优点，广泛应用于仪器仪表中，结合不同类型的传感器，可实现诸如电压、功率、频率、湿度、温度、流量、速度、厚度、角度、长度、硬度、元素、压力等物理量的测量。采用单片机控制使得仪器仪表数字化、智能化、微型化，且功能比起采用电子或数字电路更加强大。例如精密的测量设备（功率计，示波器，各种分析仪）。

（2）在工业控制中的应用

用单片机可以构成形式多样的控制系统、数据采集系统。例如工厂流水线的智能化管、电梯智能化控制、各种报警系统，与计算机联网构成二级控制系统等。

（3）在家用电器中的应用

可以这样说，现在的家用电器基本上都采用了单片机控制，从电饭褒、洗衣机、电冰箱、空调机、彩电、其他音响视频器材、再到电子秤量设备，五花八门，无所不在。

（4）在计算机网络和通信领域中的应用

现代的单片机普遍具备通信接口，可以很方便地与计算机进行数据通信，为在计算机网络和通信设备间的应用提供了极好的物质条件，现在的通信设备基本上都实现了单片机智能控制，从手机，电话机、小型程控交换机、楼宇自动通信呼叫系统、列车无线通信、再到日常工作中随处可见的移动电话，集群移动通信，无线电对讲机等。

（5）单片机在医用设备领域中的应用

单片机在医用设备中的用途亦相当广泛，例如医用呼吸机，各种分析仪，监护仪，超声诊断设备及病床呼叫系统等等。

（6）在各种大型电器中的模块化应用

某些专用单片机设计用于实现特定功能，从而在各种电路中进行模块化应用，而不要求使用人员了解其内部结构。如音乐集成单片机，看似简单的功能，微缩在纯电子芯片中（有别于磁带机的原理），就需要复杂的类似于计算机的原理。如：音乐信号以数字的形式存于存储器中（类似于ROM），由微控制器读出，转化为模拟音乐电信号（类似于声卡）。

在大型电路中，这种模块化应用极大地缩小了体积，简化了电路，降低了损坏、错误率，也方便于更换。

（7）单片机在汽车设备领域中的应用

单片机在汽车电子中的应用非常广泛，例如汽车中的发动机控制器，基于CAN总线的汽车发动机智能电子控制器，GPS导航系统，abs防抱死系统，制动系统等等。

此外，单片机在工商，金融，科研、教育，国防航空航天等领域都有着十分广泛的用途。

5 AT89C52单片机介绍

AT89C52是美国Atmel公司生产的低电压、高性能CMOS 8位单片机，片内含8KB的可反复擦写的程序存储器和12B的随机存取数据存储器（RAM），器件采用Atmel公司的高密度、非易失性存储技术生产，兼容标准MCS-51指令系统，片内配置通用8位中央处理器（CPU）和Flash存储单元，功能强大的AT89C52单片机可灵活应用于各种控制领域。AT89C52单片机属于AT89C51单片机的增强型，与Intel公司的80C52在引脚排列、硬件组成、工作特点和指令系统等方面兼容。

其主要工作特性是：

片内程序存储器内含8KB的Flash程序存储器，可擦写寿命为1000次；

片内数据存储器内含256字节内部RAM；

具有32根可编程I/O口线；

具有3个可编程定时器；

2个可编程I/O口线；

中断系统具有8个中断源；

串行口是具有一个全双工的可编程串行通信口；

低功耗工作模式有空闲模式和掉电模式；

具有可编程的3级程序锁定位；

AT89C52最高工作频率为24MHz。

功能特性描述：

AT89C52是一种低功耗、高性能CMOS8位微控制器，具有8K在系统可编程Flash存储器，使用Atmel公司的高密度、非易失性存储技术制造，与工业80C51产品指令和引脚完全兼容。片上Flash允许程序存储器在系统可编程，亦适用于常规编程器。在单芯片上，拥有灵巧的8位CPU和在系统可编程Flash，使得AT89C52为众多嵌入式控制应用系统提供高灵活、超有效的解决方案。

AT89C52具有以下标准功能：

8k字节Flash，256字节RAM，32位I/O口线，看门狗定时器，2个数据指针，三个16位定时/计数器，一个6向量2级中断结构，全双工串行口，片内晶振及时钟电路。另外，AT89C52可

降至0Hz静态逻辑操作，支持2种软件可选择节电模式。空闲模式下，CPU停止工作，允许RAM、定时/计数器、串口、中断继续工作。掉电保护方式下，RAM内容被保存，振荡器被冻结，单片机一切工作停止，知道下一个中断或硬件复位为止。8位微控制器、8K字节在系统可编程。

AT89C52有40个引脚，32个外部双向输入/输出（I/O）端口，同时内含2个外中端口，3

个16位可编程定时计数器，2个全双工串行通信口，2个读写口线，AT89C52可以按照常规方法进行编程，也可以在线编程。其将通用的微处理器和Flash存储器结合在一起，特别是可反复擦写的Flash存储器可有效的降低开发成本。

MCU

1 The definition of MCU

MCU is an integrated on a single chip a complete computer system.Even though most of his features in a small chip,but it has a need to complete the majority of computer components:CPU,memory,internal and external bus system,most will have the Core.At the same time,such as integrated communication interfaces,times,real-time

Clock and other peripheral equipment.And now the most powerful MCU microco mputer system can even voice,image,networking,input and output complex system integration on a single chip.

Also known as single-chip MCU(Microcontroller),because it was first used in the field of industrial control.Only by the single-chip CPU chip developed from the dedicated processor.The design concept is the first by a large number of peripherals and CPU in a single chip,the computer system so that smaller,more easily integrated into the complex and demanding on the volume control devices.INTEL the Z80 is one of the first design in accordance with the idea of the processor,From then on,the MCU and the development of a dedicated processor parted ways.

Early MCU 8-bit or all of the four. One of the most successful is the INTEL 8031, because 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 widely 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 widely used. After 90 years with the great development of consumer electronics, microcontroller technology has been a huge increase. With INTEL i960 series, especially the later series of widely used ARM, 32-bit microcontroller quickly replace high-end 16-bit MCU status and enter the mainstream market. The traditional 8-bit microcontroller performance have been the rapid increase capacity increase compared to 80 the number of times. Currently, high-end 32-bit microcontroller clocked over 300MHz, the performance catching the mid-90's dedicated processor, while the average model prices fall to one U.S. dollars, the most high-end [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 widely used in the full range of SCM. The handheld computers and cell phones as the core processing of high-end microcontroller can even use a dedicated Windows and Linux operating systems.

More than a dedicated MCU processor suitable for embedded systems, so it was up to the application. In fact the number of SCM is the world's largest computer. Modern human life used in almost every piece of electronic and mechanical products will be integrated single chip.Phone, telephone, calculator, home appliances, electronic toys, handheld computers and computer accessories such as a mouse with a 1-2 in both the Department of SCM. Personal computer will have a large number of SCM in the work. General car with more than 40 SCM, complex industrial control systems may even have hundreds of SCM in the same time work! SCM is not only far exceeds the number of PC and other computing the sum, or even more than the number of human

beings.

2 MCU introduced

MCU ,also known as single-chip microcontroller, it is not complete a certain logic chips, but to a computer system integrated into a chip.Equivalent to a micro-computer, and computer than just the lack of a microcontroller I / O devices. General talk: a chip becomes a computer. 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 computer the best choice.

MCU and the computer use is also similar to the module, such as CPU, memory, parallel bus, as well as the role and the same hard disk memory,is it different from the performance of these components are relatively weak in our home computer a lot ,but the price is low , there is generally no more than 10 yuan ......can use it to make some control for a class of electrical work is not very complex is sufficient.We are using automatic drum washing machines ,smoke hood, VCD and so on inside the home appliances can see it's shadow!......It is mainly as part of the core component of the control.

It is an online real-time control computer, control-line is that the scene is needed is a stronger anti-jamming ability, low cost, and this is, and off-line computer (such as home PC), the main difference.

By single-chip process ,and can be amended.Through different procedures to achieve different functions, in particular special unique features, this is another device much effort ne eds to be done, some great efforts are very difficult to do. A not very complex functions if the 50's with the United States developed 74 series, or the 60's CD4000 series of these pure hardware buttoned, then the circuit must be a large PCB board! But if the United States if the 70's with a series of successful SCM market, the result will be a drastic change! Just because you are prepared by microcomputer programs can achieve high intelligence, high efficiency and high reliability!

As the microcontroller on the cost-sensitive, so now the dominant software or the lowest level assembly language, which is the lowest level in addition to more than binary machine code language, and as so low why is the use? Many high-level language has reached the level of visual programming Why is not it? The reason is simply that there is no home computer as a single chip CPU, not as hard as a mass storage device.A visualization of small high-level language program which even if only one button, will reach tens of K of size! For the home PC'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 compilation of a lot of use. The same token, if the giant computer 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 computer age. However, this computer, usually refers to the personal computer, referred to as PC. It consists of the host, keyboard,

monitor and other components. Another type of computer, most people do not know how. This computer is to give all kinds of intelligent machines single chip (also known as micro-controller). As the name suggests, this computer 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, real-time industrial control, communications 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 complicated, 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.

3 MCU history

Single-chip 70 was born in the late 20th century, experienced a SCM, MCU, SOC three stages.

（1）SCM the single chip microcomputer (Single Chip Microcomputer) stage, mainly seeking the best of the best single form of embedded systems architecture. "Innovation model" success, laying the SCM and general computer completely different path of development. In the open road of independent development of embedded systems, Intel Corporation contributed.

（2）MCU the micro-controller (Micro Controller Unit) stage, the main direction of technology development: expanding to meet the embedded applications, the target system requirements for the various peripheral circuits and interface circuits, highlight the object of intelligent control.It involves the areas associated with the object system, therefore, the development of MCU's responsibility inevitably falls on electrical, electronics manufacturers. From this point of view, Intel faded MCU development has its objective factors. In the development of MCU, the most famous manufacturers as the number of Philips Corporation.

Philips company in embedded applications, its great advantage, the MCS-51 single-chip micro-computer from the rapid development of the micro-controller. Therefore, when we look back at the path of development of embedded systems, do not forget Intel and Philips in History. （3）Embedded system microcontroller is an independent development path, the MCU important factor in the development stage, is seeking applications to maximize the solution on the chip; Therefore, the development of dedicated single chip SOC trend of the natural form. As the microelectronics, IC design, EDA tools development, application system based on MCU S OC design have greater development. Therefore, the understanding of the microcontroller chip microcomputer can be, extended to the single-chip micro-controller applications.

4 MCU applications

At present,MCU to infiltrate all areas of our lives, which is almost difficult to find

traces of the field without SCM. Missile navigation equipment, aircraft, all types of instrument control, computer network communications and data transmission, industrial automation, real-time process control and data processing, extensive use of various smart IC card, civilian luxury car security system, video recorder, camera, fully automatic washing machine control, and program-controlled toys, electronic pet, etc., which are inseparable from the microcontroller. Not to mention the area of robot control, intelligent instruments, medical equipment was. Therefore, the MCU learning, development and application of the large number of computer applications and intelligent control of the scientists, engineers.

SCM is widely used in instruments and meters, household appliances, medical equipment, aerospace, specialized equipment, intelligent management and process control fields, roughly divided into the following several areas:

（1）In the application of Intelligent Instruments

SCM has a small size, low power consumption, controlling function, expansion flexibility, the advantages of miniaturization and ease of use, widely used instrument, combining different types of sensors can be realized Zhuru voltage, power, frequency, humidity, temperature, flow, speed, thickness, angle, length, hardness, elemental, physical pressure measurement. SCM makes use of digital instruments, intelligence, miniaturization, and functionality than electronic or digital circuits more powerful. Such as precision measuring equipment (power meter, oscilloscope, various analytical instrument).

（2）In the industrial control application

With the MCU can constitute a variety of control systems, data acquisition system. Such as factory assembly line of intelligent control,all kinds of alarm systems,and computer networks constitute a secondary control system.

（3）In the Appliance of Household appliances

It can be said that the appliances are basically using SCM, praise from the electric rice, washing machines, refrigerators, air conditioners, color TV, and other audio video equipment, to the electronic weighing equipment, varied, and omnipresent.（4）In the field of computer networks and communications applications MCU general with modern communication interface, can be easy with the computer data communication, networking and communications in computer applications between devices had excellent material conditions, are basically all communication equipment to achieve a controlled by MCU from mobile phone, telephone, mini-program-controlled switchboards, building automated communications call system, train radio communication, to the daily work can be seen everywhere in the mobile phones, trunked mobile radio, walkie-talkies, etc..

（5）Microcomputer in the field of medical device applications

MCU in the use of medical devices is also quite extensive, such as medical respirator, the various analyzers, monitors, ultrasound diagnostic equipment and

hospital beds, etc. call system.

（6）In a variety of major appliances in the modular applications

Designed to achieve some special single specific function to be modular in a variety of circuit applications, without requiring the use of personnel to understand its internal structure. If music integrated single chip, seemingly simple function, miniature electronic chip in the net (the principle is different from the tape machine), you need a computer similar to the principle of the complex. Such as: music signal to digital form stored in memory (like ROM), read by the microcontroller, analog music into electrical signals (similar to the sound card).

In large circuits, modular applications that greatly reduce the volume, simplifies the circuit and reduce the damage, error rate, but also easy to replace.

（7）Microcontroller in the application field of automotive equipment SCM in automotive electronics is widely used, such as a vehicle engine controller, CAN bus-based Intelligent Electronic Control Engine, GPS navigation system, abs anti-lock braking system, brake system, etc..

In addition, the MCU in business, finance, research, education, national defense, aerospace and other fields has a very wide range of applications.

5.AT89C52 chip explains

The AT89C52 is a low-power,high-performance CMOS 8-bit microcomputer with 8 K bytes of Flash programmable and erasable read only memory(PEROM).The device is manufactured using Atmel's high density nonvolatile memory technology and is compatible with the industry standard 80C51 and 80C52 instruction set and pinot.The on-chip Flash allows the program memory to be reprogrammed in-system or by a conbventional onwolatile memory programmer.By combining a versatile 8-bit CPU with Flash on a monolithic chip,the Atmel AT89C52 is a powerful microcomputer,which provides a highly flexible and cost effective solution to many embedded control applications.

Eatures:

8 K bytes of In-system Reprogrammable Flash Memory;Endurance:1000 Write/Erase Cycles

256×8 bit Internal RAM

32 Programmable I/O Lines

Three 16-Bit Timer/Counters

Eight Interrupt Sources

Programmable Serial Channel

Low Power Idle and Power Down Modes

Three-Level Program Memory Lock

Fully Static Operation:0 Hz to 24 MHz

Description

The AT89C52 is a low-power,high-performance COMS 8-bit microcomputer

with 8K bytes of Flash programmable and erasable read only memory(PEROM).The device is manufactured using Atmel's high density nonvolatile memory technology and is compatible with the industry standard 80C51 and 80C52 instruction set and pinot.The on-chip Flash allows the program memory to be reprogrammed in-system or by a conventional onvolatile memory programmer.By combining a versatile 8-bit CPU with Flash on a monolithic chip,the Atmel AT89C52 is a powerful microcomputer,which provides a highly flexible and cost effective solution to many embedded control applications

The AT89C52 provides the following standard features:

8k bytes of Flash ,256 bytes of RAM,32 I/O lines,three 16-bit timer/counters,a six-vector two-level interrupt architecture , a full duplex serial port,on-chip oscillator,and clock circuitry . In addition, the AT89C52 is designed with static logic of operation down to zero frequency and supports two software selectable power saving modes. The Idle Mode stops the CPU while allowing the RAM,timer/counter,serial port,and interrupt system to continue functioning. The Power Down Mode saves the RAM contents but freezes the oscillator,disabling all other chip functions until the next hardware rest.

AT89C52 40 pins, 32 external bi-directional input/output(I/O)ports, and includes two external interrupt ports, three 16-bit programmable timer counters, two full duplex serial port, 2 a read-write port line,AT89C52 can be programmed according to conventional method, also available online programming. The generic microprocessor and Flash memo ry together, particularly when repeated erase the Flash memory can effectively reduce the development costs.

步进电机及单片机英文文献及翻译

外文文献： Knowledge of the stepper motor What is a stepper motor： Stepper motor is a kind of electrical pulses into angular displacement of the implementing agency. Popular little lesson: When the driver receives a step pulse signal, it will drive a stepper motor to set the direction of rotation at a fixed angle (and the step angle). You can control the number of pulses to control the angular displacement, so as to achieve accurate positioning purposes; the same time you can control the pulse frequency to control the motor rotation speed and acceleration, to achieve speed control purposes. What kinds of stepper motor sub-： In three stepper motors: permanent magnet (PM), reactive (VR) and hybrid (HB) permanent magnet stepper usually two-phase, torque, and smaller, step angle of 7.5 degrees or the general 15 degrees; reaction step is generally three-phase, can achieve high torque output, step angle of 1.5 degrees is generally, but the noise and vibration are large. 80 countries in Europe and America have been eliminated; hybrid stepper is a mix of permanent magnet and reactive advantages. It consists of two phases and the five-phase: two-phase step angle of 1.8 degrees while the general five-phase step angle of 0.72 degrees generally. The most widely used Stepper Motor. What is to keep the torque (HOLDING TORQUE) How much precision stepper motor? Whether the cumulative： The general accuracy of the stepper motor step angle of 3-5%, and not cumulative.

AT89C51单片机外文翻译

AT89C51外文翻译 Description The AT89C51 is a low-power, high-performance CMOS 8-bit microcomputer with 4K bytes of Flash Programmable and Erasable Read Only Memory (PEROM). The device is manufactured using Atmel’s high density nonvolatile memory technology and is compatible with the industry standard MCS-51? instruction-set and pinout. The on-chip Flash allows the program memory to be reprogrammed in-system or by a conventional nonvolatile memory programmer. By combining a versatile 8-bit CPU with Flash on a monolithic chip, the Atmel AT89C51 is a powerful microcomputer which provides a highly flexible and cost effective solution to many embedded control applications. Features ? Compatible with MCS-51? Products ? 4K Bytes of In-System Reprogrammable Flash Memory – Endurance: 1,000 Write/Erase Cycles ? Fully Static Operation: 0 Hz to 24 MHz ? Three-Level Program Memory Lock ? 128 x 8-Bit Internal RAM ? 32 Programmable I/O Lines ? Two 16-Bit Timer/Counters ? Six Interrupt Sources ? Programmable Serial Channel ? Low Power Idle and Power Down Modes The AT89C51 provides the following standard features: 4K bytes of Flash,128 bytes of RAM, 32 I/O lines, two 16-bit timer/counters, a five vector two-level interrupt architecture, a full duplex serial port, on-chip oscillator and clock circuitry. In addition, the AT89C51 is designed with static logic for operation down to zero frequency and supports two software selectable power saving modes. The Idle Mode stops the CPU while allowing the RAM, timer/counters, serial port and interrupt system to continue functioning. The Power-down Mode saves the RAM contents but freezes the oscillator disabling all other chip functions until the next hardware reset.

单片机方面毕业设计外文文献翻译

单片机方面毕业设计外文文献翻译

中文译文 单片机 单片机也被称为微控制器（Microcontroller Unit），常见英文字母的缩写MCU表示单片机，它最早是被用在工业控制领域。单片机由芯片内仅有CPU的专用处理器发展而来。最早的设计理念是经过将大量外围设备和CPU集成在一个芯片中，使计算机系统更小，更容易集成进复杂的而对体积要求严格的控制设备当中。INTEL的Z80是最早按照这种思想设计出的处理器，从此以后，单片机和专用处理器的发展便分道扬镳。 早期的单片机都是8位或4位的。其中最成功的是INTEL 的8031，因为简单可靠而性能不错获得了很大的好评。此后在8031上发展出了MCS51系列单片机系统。基于这一系统的单片机系统直到现在还在广泛使用。随着工业控制领域要求的提高，开始出现了16位单片机，但因为性价比不理想并未得到很广泛的应用。90年代后随着消费电子产品大发展，单片机技术得到了巨大提高。随着INTEL i960系列特别是后来的ARM系列的广泛应用，32位单片机迅速取代16位单片机的高端地位，而且进入主流市场。而传统的8位单片机的性能也得到了飞速提高，处理能力比起80年代提高了数百倍。当前，高端的32位单片机主频已经超过300MHz，性能直追90年代中期的专用处理器，而普通的型号出厂价格跌落至1美元，最高端[1]的型号也只有10美元。当代单片机系统已经不再只在裸机环境下开发和

使用，大量专用的嵌入式操作系统被广泛应用在全系列的单片机上。而在作为掌上电脑和手机核心处理的高端单片机甚至能够直接使用专用的Windows和Linux操作系统。 单片机比专用处理器更适合应用于嵌入式系统，因此它得到了最多的应用。事实上单片机是世界上数量最多的计算机。现代人类生活中所用的几乎每件电子和机械产品中都会集成有单片机。手机、电话、计算器、家用电器、电子玩具、掌上电脑以及鼠标等电脑配件中都配有1-2部单片机。而个人电脑中也会有为数不少的单片机在工作。汽车上一般配备40多部单片机，复杂的工业控制系统上甚至可能有数百台单片机在同时工作！单片机的数量不但远超过PC机和其它计算的总和，甚至比人类的数量还要多。 单片机又称单片微控制器,它不是完成某一个逻辑功能的芯片,而是把一个计算机系统集成到一个芯片上。相当于一个微型的计算机，和计算机相比，单片机只缺少了I/O设备。概括的讲：一块芯片就成了一台计算机。它的体积小、质量轻、价格便宜、为学习、应用和开发提供了便利条件。同时，学习使用单片机是了解计算机原理与结构的最佳选择。 单片机内部也用和电脑功能类似的模块，比如CPU，内存，并行总线，还有和硬盘作用相同的存储器件，不同的是它的这些部件性能都相对我们的家用电脑弱很多，不过价钱也是低的，一般不超过10元即可......用它来做一些控制电器一类不

单片机外文翻译

杭州电子科技大学信息工程学院毕业设计（论文）外文文献翻译 毕业设计（论文）题目用单片机实现的数字时钟电路设计文献综述题目单片机控制系统系电子工程 专业电子信息科学与技术 姓名郭筱楠 班级08091911 学号08919115 指导教师王维平

单片机控制系统 广义地说，微型计算机控制系统（单片机控制系统）是用于处理信息的，这种被用于处理的信息可以是电话交谈，也可以是仪器的读数或者是一个企业的帐户，但是各种情况下都涉及到相同的主要操作：信息的处理、信息的存储和信息的传递。在常规的电子设计中，这些操作都是以功能平台方式组合起来的，例如计数器，无论是电子计数器还是机械计数器，都要存储当前的数值，并且按要求将该数值增加1。一个系统例如采用计数器的电子钟之类的任一系统要使其存储和处理能力遍布整个系统，因为每个计数器都能存储和处理一些数字。 现如今，以微处理器为基础的系统从常规的处理方法中分离了出来，它将信息的处理，信息的存储和信息的传输三个功能分离形成不同的系统单元。这种主要将系统分成三个主要单元的分离方法是冯-诺依曼在20世纪40年代所设想出来的，并且是针对微计算机的设想。从此以后基本上所有制成的计算机都是用这种结构设计的，尽管他们包含着宽广的物理形式与物理结构，但从根本上来说他们均是具有相同基本设计的计算机。 在以微处理器为基础的系统中，处理是由以微处理器为基础的系统自身完成的。存储是利用存储器电路，而从系统中输入和输出的信息传输则是利用特定的输入/输出（I/O）电路。要在一个以微处理器为基础的时钟中找出执行具有计数功能的一个特殊的硬件组成部分是不可能的，因为时间存储在存储器中，而在固定的时间间隔下由微处理器控制增值。但是，规定系统运转过程的软件却规定了包含实现计数器计数功能的单元部分。由于系统几乎完全由软件所定义，所以对微处理器结构和其辅助电路这种看起来非常抽象的处理方法使其在应用时非常灵活。这种设计过程主要是软件工程，而且在生产软件时，就会遇到产生于常规工程中相似的构造和维护问题。 图1.1 微型计算机的三个组成部分 图1.1显示出了微型计算机中这三个单元在一个微处理器控制系统中是如何按照机器中的信息通信方式而联接起来的。该系统由微处理器控制，微处理器能够对其自身的存储器和输入/输出单元的信息传输进行管理。外部的连接部分与

at89c52单片机中英文资料对照外文翻译文献综述

at89c52单片机简介 中英文资料对照外文翻译文献综述 A T89C52 Single-chip microprocessor introduction Selection of Single-chip microprocessor 1. Development of Single-chip microprocessor The main component part of Single-chip microprocessor as a result of by such centralize to be living to obtain on the chip，In immediate future middle processor CPU。Storage RAM immediately﹑memoy read ROM﹑Interrupt system、Timer /'s counter along with I/O's rim electric circuit awaits the main microcomputer section，The lumping is living on the chip。Although the Single-chip microprocessor r is only a chip，Yet through makes up and the meritorous service be able to on sees，It had haveed the calculating machine system property，calling it for this reason act as Single-chip microprocessor r minisize calculating machine SCMS and abbreviate the Single-chip microprocessor。 1976Year the Inter corporation put out 8 MCS－48Set Single-chip microprocessor computer，After being living more than 20 years time in development that obtain continuously and wide-ranging application。1980Year that corporation put out high performance MCS －51Set Single-chip microprocessor。This type of Single-chip microprocessor meritorous service capacity、The addressing range wholly than early phase lift somewhat，Use also comparatively far more at the moment。1982Year that corporation put out the taller 16 Single-chip microprocessor MCS of performance once

51单片机外文文献

The Introduction of AT89C51 Description The AT89C51 is a low-power, high-performance CMOS 8-bit microcomputer with 4K bytes of Flash programmable and erasable read only memory (PEROM). The device is manufactured using Atmel’s high-density nonvolatile memory technology and is compatible with the industry-standard MCS-51 instruction set. The on-chip Flash allows the program memory to be reprogrammed in-system or by a conventional nonvolatile memory programmer. By combining a versatile 8-bit CPU with Flash on a monolithic chip, the Atmel AT89C51 is a powerful microcomputer which provides a highly-flexible and cost-effective solution to many embedded control applications. Function characteristic The AT89C51 provides the following standard features: 4K bytes of Flash, 128 bytes of RAM, 32 I/O lines, two 16-bit timer/counters, one 5 vector two-level interrupt architecture, a full duplex serial port, one-chip oscillator and clock circuitry. In addition, the AT89C51 is designed with static logic for operation down to zero frequency and supports two software selectable power saving modes. The Idle Mode stops the CPU while allowing the RAM, timer/counters, serial port and interrupt system to continue functioning. The Power-down Mode saves the RAM contents but freezes the oscillator disabling all other chip functions until the next hardware reset. Pin Description VCC：Supply voltage. GND：Ground.

单片机外文文献翻译

外文文献一单片机简介 单片机是一种集成在电路芯片，是采用超大规模集成电路技术把具有数据处理能力的中央处理器CPU随机存储器RAM、只读存储器ROM、多种I/O口和中断系统、定时器/计时器等功能（可能还包括显示驱动电路、脉宽调制电路、模拟多路转换器、A/D转换器等电路）集成到一块硅片上构成的一个小而完善的计算机系统。单片机也被称为微控制器（Microcontroller），是因为它最早被用在工业控制领域。单片机由芯片内仅有CPU的专用处理器发展而来。最早的设计理念是通过将大量外围设备和CPU集成在一个芯片中，使计算机系统更小，更容易集成进复杂的而对体积要求严格的控制设备当中。INTEL的Z80是最早按照这种思想设计出的处理器，从此以后，单片机和专用处理器的发展便分道扬镳。 二、单片机的发展趋势 现在可以说单片机是百花齐放，百家争鸣的时期，世界上各大芯片制造公司都推出了自己的单片机，从8位、16位到32位，数不胜数，应有尽有，有与主流C51系列兼容的，也有不兼容的，但它们各具特色，互成互补，为单片机的应用提供广阔的天地。 纵观单片机的发展过程，可以预示单片机的发展趋势，大致有： 1.低功耗CMOS MCS-51系列的8031推出时的功耗达630mW，而现在的单片机普遍都在100mW左右，随着对单片机功耗要求越来越低，现在的各个单片机制造商基本都采用了CMOS(互补金属氧化物半导体工艺)。象80C51就采用了HMOS(即高密度金属氧化物半导体工艺)和CHMOS(互补高密度金属氧化物半导体工艺)。CMOS虽然功耗较低，但由于其物理特征决定其工作速度不够高，而CHMOS则具备了高速和低功耗的特点，这些特征，更适合于在要求低功耗象电池供电的应用场合。所以这种工艺将是今后一段时期单片机发展的主要途径。 2.微型单片化 现在常规的单片机普遍都是将中央处理器(CPU)、随机存取数据存储(RAM)、只读程序存储器(ROM)、并行和串行通信接口，中断系统、定时电路、时钟电路集成在一块单一的芯片上，增强型的单片机集成了如A/D转换器、PMW(脉宽调制电路)、WDT(看门狗)、有些单片机将LCD(液晶)驱动电路都集成在单一的芯片上，这样 单片机包含的单元电路就更多，功能就越强大。甚至单片机厂商还可以根据用户的要求量身定做，制造出具有． 自己特色的单片机芯片。此外，现在的产品普遍要求体积小、重量轻，这就要求单片机除了功能强和功耗低外，还要求其体积要小。现在的许多单片机都具有多种封装形式，其中SMD(表面封装)越来越受欢迎，使得由单片机构成的系统正朝微型化方向发展。 3.主流与多品种共存 现在虽然单片机的品种繁多，各具特色，但仍以80C51为核心的单片机占主流，兼容其结构和指令系统的有PHILIPS公司的产品，ATMEL公司的产品和中国台湾

MCS_51系列单片机中英文资料对照外文翻译文献综述

MCS-51系列单片机 中英文资料对照外文翻译文献综述 Structure and function of the MCS-51 series Structure and function of the MCS-51 series one-chip computer MCS-51 is a name of a piece of one-chip computer series which Intel Company produces. This company introduced 8 top-grade one-chip computers of MCS-51 series in 1980 after introducing 8 one-chip computers of MCS-48 series in 1976. It belong to a lot of kinds this line of one-chip computer the chips have, such as 8051, 8031, 8751, 80C51BH, 80C31BH,etc., their basic composition, basic performance and instruction system are all the same.8051 daily representatives-51 serial one-chip computers. A one-chip computer 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 depositing 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/8K B ), is used to preserve the

(完整word版)单片机外文文献翻译

中文资料原文 单片机 单片机也被称为微控制器（Microcontroller Unit），常用英文字母的缩写MCU表示单片机，它最早是被用在工业控制领域。单片机由芯片内仅有CPU的专用处理器发展而来。最早的设计理念是通过将大量外围设备和CPU集成在一个芯片中，使计算机系统更小，更容易集成进复杂的而对体积要求严格的控制设备当中。INTEL的Z80是最早按照这种思想设计出的处理器，从此以后，单片机和专用处理器的发展便分道扬镳。 早期的单片机都是8位或4位的。其中最成功的是INTEL的8031，因为简单可靠而性能不错获得了很大的好评。此后在8031上发展出了MCS51系列单片机系统。基于这一系统的单片机系统直到现在还在广泛使用。随着工业控制领域要求的提高，开始出现了16位单片机，但因为性价比不理想并未得到很广泛的应用。90年代后随着消费电子产品大发展，单片机技术得到了巨大提高。随着INTEL i960系列特别是后来的ARM系列的广泛应用，32位单片机迅速取代16位单片机的高端地位，并且进入主流市场。而传统的8位单片机的性能也得到了飞速提高，处理能力比起80年代提高了数百倍。目前，高端的32位单片机主频已经超过300MHz，性能直追90年代中期的专用处理器，而普通的型号出厂价格跌落至1美元，最高端[1]的型号也只有10美元。当代单片机系统已经不再只在裸机环境下开发和使用，大量专用的嵌入式操作系统被广泛应用在全系列的单片机上。而在作为掌上电脑和手机核心处理的高端单片机甚至可以直接使用专用的Windows和Linux操作系统。 单片机比专用处理器更适合应用于嵌入式系统，因此它得到了最多的应用。事实上单片机是世界上数量最多的计算机。现代人类生活中所用的几乎每件电子和机械产品中都会集成有单片机。手机、电话、计算器、家用电器、电子玩具、掌上电脑以及鼠标等电脑配件中都配有1-2部单片机。而个人电脑中也会有为数不少的单片机在工作。汽车上一般配备40多部单片机，复杂的工业控制系统上甚至可能有数百台单片机在同时工作！单片机的数量不仅远超过PC机和其他计算的总和，甚至比人类的数量还要多。 单片机又称单片微控制器,它不是完成某一个逻辑功能的芯片,而是把一个计算机系统集成到一个芯片上。相当于一个微型的计算机，和计算机相比，单片机只缺少了I/O设备。概括的讲：一块芯片就成了一台计算机。它的体积小、质量轻、价格便宜、为学习、应用和开发提供了便利条件。同时，学习使用单片机是了解计算机原理与结构的最佳选择。

单片机外文翻译--STC89C52处理芯片

外文资料翻译 STC89C52 processi ng chip Prime features: With MCS - 51 SCM product compatibility, 8K bytes in the system programmable Flash memory, 1000 times CaXie cycle, the static operation: 0Hz ~ 33Hz, triple encryption program memory, 32 programmed I/O port, three 16 timer/counter, the eight uninterrupted dual-career UART serial passage, low power consumption, leisure and fall after fall electric power mode can be awakened and continuous watchdog timer and double-number poin ter, power ide ntifier. Efficacy: characteristics STC89C52 is one kind of low power consumption, high CMOS8 bit micro-co ntroller, 8K in system programmable Flash memory. Use high-de nsity nonv olatile storage tech no logy, and in dustrial 80C51 product in structi on and pin fully compatible. The Flash memory chips allows programs in the system, also suitable for programmable conventional programming. In a single chip, have clever 8 bits CPU and on li ne system programmable Flash, in crease STC89C52 for many embedded control system to provide high vigorous application and useful solutions. STC89C52 has following standard efficacy: 8k byte Flash RAM, 256 bytes, 32 I/O port, the watchdog timer, two, three pointer numerical 16 timer/counter, a 6 vector level 2 continuous structure, the serial port, working within crystals and horological circuit. In addition, 0Hz AT89S52 can drop to the static logic operation, support two software can choose power saving mode. Idle mode, the CPU to stop working, and allows the RAM, timer/c oun ters, serial, continu ous to work. Protectio n asa na patter n, RAM content is survival, vibrators frozen, SCM, until all the work under a continuous or hardware reset. 8-bit microcontrollers 8K bytes in the system programmable Flash AT89S52 devices. Mouth: P0 P0 mouth is a two-way ope n drain I/O. As export, each can drive eight TTL logic level. For P0 port to write "1", foot as the high impeda nee in put. When access to exter nal programs and nu merical memory, also known as

AT89C51单片机英文文献附带翻译

AT89C51的概况 一 AT89C51应用 单片机广泛应用于商业：诸如调制解调器，电动机控制系统，空调控制系统，汽车发动机和其他一些领域。这些单片机的高速处理速度和增强型外围设备集合使得它们适合于这种高速事件应用场合。然而，这些关键应用领域也要求这些单片机高度可靠。健壮的测试环境和用于验证这些无论在元部件层次还是系统级别的单片机的合适的工具环境保证了高可靠性和低市场风险。Intel 平台工程部门开发了一种面向对象的用于验证它的AT89C51 汽车单片机多线性测试环境。这种环境的目标不仅是为AT89C51 汽车单片机提供一种健壮测试环境，而且开发一种能够容易扩展并重复用来验证其他几种将来的单片机。开发的这种环境连接了AT89C51。本文讨论了这种测试环境的设计和原理，它的和各种硬件、软件环境部件的交互性，以及如何使用AT89C51。 1.1 介绍 8 位AT89C51 CHMOS 工艺单片机被设计用于处理高速计算和快速输入/输出。MCS51 单片机典型的应用是高速事件控制系统。商业应用包括调制解调器，电动机控制系统，打印机，影印机，空调控制系统，磁盘驱动器和医疗设备。汽车工业把MCS51 单片机用于发动机控制系统，悬挂系统和反锁制动系统。AT89C51 尤其很好适用于得益于它的处理速度和增强型片上外围功能集，诸如：汽车动力控制，车辆动态悬挂，反锁制动和稳定性控制应用。由于这些决定性应用，市场需要一种可靠的具有低干扰潜伏响应的费用-效能控制器，服务大量时间和事件驱动的在实时应用需要的集成外围的能力，具有在单一程序包中高出平均处理功率的中央处理器。拥有操作不可预测的设备的经济和法律风险是很高的。一旦进入市场，尤其任务决定性应用诸如自动驾驶仪或反锁制动系统，错误将是财力上所禁止的。重新设计的费用可以高达500K 美元，如果产品族享有同样内核或外围设计缺陷的话，费用会更高。另外，部件的替代品领域是极其昂贵的，因为设备要用来把模块典型地焊接成一个总体的价值比各个部件高几倍。为了缓和这些问题，在最坏的环境和电压条件下对这些单片机进行无论在部件级别还是系统级别上的综合测试是必需的。Intel Chandler 平台工程组提供了各种单片机和处理器的系统验证。这种系统的验证处理可以被分解为三个主要部分。系统的类型和应用需求决定了能够在设备上执行的测试类型。 1.2 AT89C51提供以下标准功能：

单片机的外文文献及中文翻译

SCM is an integrated circuit chip, is the use of large scale integrated circuit technology to a data processing capability of CPU CPU random access memory RAM, read-only memory ROM, a variety of I / O port and interrupt system, timers / timer functions (which may also include display driver circuitry, pulse width modulation circuit, analog multiplexer, A / D converter circuit) integrated into a silicon constitute a small and complete computer systems. SCM is also known as micro-controller (Microcontroller), because it is the first to be used in industrial control. Only a single chip by the CPU chip developed from a dedicated processor. The first design is by a large number of peripherals and CPU on a chip in the computer system, smaller, more easily integrated into a complex and demanding on the volume control device which. The Z80 INTEL is the first designed in accordance with this idea processor, then on the development of microcontroller and dedicated processors will be parting ways. Are 8-bit microcontroller early or 4 bits. One of the most successful is the INTEL 8031, for a simple, reliable and good performance was a lot of praise. Then developed in 8031 out of MCS51 MCU Systems. SCM systems based on this system until now is still widely used. With the increased requirements of industrial control field, began a 16-bit microcontroller, but not ideal because the cost has not been very widely used. After 90 years with the great development of consumer electronics, microcontroller technology has been a huge increase. With INTEL i960 series, especially the later series of widely used ARM, 32-bit microcontroller quickly replace high-end 16-bit MCU status and enter the mainstream market. The traditional 8-bit microcontroller performance have been the rapid increase capacity increase compared to 80 the number of times. Currently, high-end 32-bit microcontroller clocked over 300MHz, the performance catching the mid-90s dedicated processor, while the average model prices fall to one U.S. dollar, the most high-end [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 widely used in the full range of SCM. The handheld computers and cell phones as the core processing of high-end microcontroller can even use a dedicated Windows and Linux operating systems. SCM is more suitable than the specific processor used in embedded systems, so it was up to the application. In fact the number of SCM is the world's largest computer. Modern human life used in almost every piece of electronic and mechanical products will be integrated single chip. Phone, telephone, calculator, home appliances, electronic toys, handheld computers and computer accessories such as a mouse with a 1-2 in both the Department of SCM. Personal computer will have a large number of SCM in the work. General car with more than 40 microcontroller, a complex industrial control systems may even hundreds of single chip at the same time work! SCM is not only far exceeds the number of PC and other computing the sum, or even more than the number of human beings. Single chip, also known as single-chip microcontroller, it is not complete a certain logic chips, but to a computer system integrated into a chip. Equivalent to a

关于51单片机英文文献的英文翻译

利用单片机的定时器 6.1 前言 这一章包含一个描述的定时器系统微控制器，包括通用定时器，该定时器，和看门狗。 6.2 总体结构和功能，计时器系统 时间是必不可少的操作微控制器系统，可以生成信号的精确确定的期限，或外部事件计数。这原因，定时器子系统，是目前所有的微控制器的实现，和涵盖的范围广泛的功能包括： ?生成精确的时间间隔 ?测量时间的外部事件 ?计数外部事件。 多数微控制器提供专用定时器，或使用通用计时器实现以下功能： ?实时时钟 ?产生的脉冲宽度调制（脉宽调制）信号 ?看门狗检测程序失控情况。 虽然有很大的差异在不同的实现通用定时器在不同的微控制器，有许多相似在操作的原则和结构的定时器子系统。 图6.1显示了一个定时器系统总体框图，说明原则实施最单片机定时器。核心要素的定时器子系统是一个计数器，tcnt（8或16位在长度），这可能是读或写的软件（有时）。时钟tcnt 得到从系统时钟，除以一个可编程分频器，或外部时钟应用到一个单片机引脚。软件控制的计时器68使用6单片机定时器。

采用控制寄存器晶体管和信息方面的各种事件相关的计时器，可以读取状态寄存器tflg。几种工作模式是可能的计时器： 定时器溢出。在这种模式下，如果感兴趣的是当tcnt计数器达到它的最大数量和返回到零在下一个时钟脉冲。溢出信号这标志着这一事件是应用于中断控制逻辑（Ⅱ），这可能产生一个中断请求处理器。之间的时间间隔连续溢出控制通过修改输入时钟频率应用到tcnt，或以书面tcnt 一初始值的计算。 ?输入捕获。在这种经营模式，内容tcnt此刻的发生外部事件，定义边缘的一个输入信号，转移在捕获寄存器（民事），和一个中断请求可能会生成。由比较连续值捕获率，有可能确定之间的时间间隔的外部事件。 ?输出比较。在这种经营模式，内容tcnt不断比较了硬件的内容的光学字符识别（比较寄存器的输出）指数字比较器的比较。当一个寄存器的内容比赛中，一个中断请求可能会生成。或者，可以比较匹配通过编程改变现状的一个或多个输出线。 ?外部事件计数器。在这种经营模式，输入tcnt连接一个单片机输入线，和tcnt计数脉冲与外部事件。该软件是了解记录一些外部通过阅读tcnt事件。 6.3 特点鲜明的通用定时器HC 11 16位tcnt计数器HC 11可以依靠内部时钟，只有向上的。它可以读取软件，但不能被清除或书面。分频器是一个可编程的4位计数器，它将系统时钟的1，4，8，或16。有四个16位输出比较寄存器（光学字符识别），称为toc1，toc2，toc3，和toc4，三输入捕获寄存器（民事），称为tic1，tic2，和tic3，和一个额外的寄存器，可通过软件配置为五分之一 光学字符识别寄存器，笔名TOC五，或作为四分之一个输入捕获寄存器tic4。各种定时器功能相关的输入/输出线端口，如图所示在表6.1。 表6.1 替代功能的输入/输出线端口 1控制和状态寄存器的HC 11定时器虽然反tcnt，和分频器是独一无二的，在场的八民事/光学字符识别寄存器，各有不同的状态标志，相关的输入/输出线，随着可能产生不同的中断请求，