关于单片机英文文献(上)
INTRODUCTION TO MICROCONTROLLERS
What are microcontrollers? They are what their name suggests. Today they can be found in almost any complex electronic device - from portable music devices to washing machines to your car. They are programmable, cheap, small, can handle abuse, require almost zero power, and there are so many variaties to suit every need. This is what makes them so useful for robotics - they are like tiny affordable computers that you can put right onto your robot.
Augmented Microcontrollers and Development Boards In a pure sense, a microcontroller is just an IC (integrated circuit, or a black chip thing with pins coming out of it>. However it is very common to add additional external components, such as a voltage regulator, capacitors, LEDs, motor driver, timing crystals, rs232, etc to the basic IC. Formally, this is called an augmented microcontroller. But in reality, most people just say 'microcontroller' even if it has augmentation. Other abbreviations would be uncontroller and MicroController Unit (MCU>. Usually when I say 'microcontroller' what I really mean to say is 'augmented microcontroller.'
As a beginner it is probably best to buy an augmented microcontroller. Why? Well because they have tons of goodies built onto them that are all assembled and debugged for you. They also often come with tech support, sample code, and a community of people to help you with them. My microcontroller parts list shows the more popular types that you can buy. They tend to cost from $30 to $150 depending on the features. This will give you a good introductory to microcontroller programming without having to be concerned with all the technical stuff.
In the long term however you should build your own augmented microcontroller so that you may understand them better. The advantage to making your own is that it will probably cost you from $10-$30.
Between getting a full augmented board and doing it yourself is something called a development board. These boards come pre-augmented with just the bare basics to get you started. They are designed for prototyping and testing of new ideas very quickly. They typically cost between $15 and $40.
What comes with the IC?There is a huge variety of microcontrollers out on the market, but I will go over a few common features that you will find useful for your robotics project.
For robots, ore important than any other feature on a microcontroller, is the I/O ports. Input ports are used for taking in sensor data, while output is used for sending commands to external hardware such as servos. There are two types of I/O ports, analog and digital.
Analog Input Ports Analog Ports are necessary to connect sensors to your robot. Also known as an analog to digital converter (ADC>, they recieve analog signals and convert them to a
digital number within a certain numerical range.
So what is analog? Analog is a continuous voltage range and is typically found with sensors. However computers can only operate in the digital realm with 0's and 1's. So how does a microcontroller convert an analog signal to a digital signal?
First, the analog is measured after a predefined period of time passes. At each time period, the voltage is recorded as a number. This number then defines a signal of 0's and 1's as shown:
The advantage of digital over analog is that digital is much better at eliminating background noise. Cell phones are all digital today, and although the digital signal is less representative than an analog signal, it is much less likely to degrade since computers can restore damaged digital signals. This allows for a clearer output signal to talk to your mom or whoever. MP3's are all digital too, usually encoded at 128 kbps. Higher bit rates obviously mean higher quality because they better represent the analog signal. But higher bit rates also require more memory and processing power.
Most microcontrollers today are 8 bit, meaning they have a
range of 256 (2^8=256>. There are a few that are 10 bit, 12 bit, and even 32 bit, but as you increase precision you also need a much faster processor.
What does this bit stuff mean for ADC? For example, suppose a sensor reads 0V to an 8 bit ADC. This would give you a digital ouput of 0. 5V would be 255. Now suppose a sensor gave an
output of 2.9V, what would the ADC output be?
Doing the math:
2.9V/5V = X/255 X = 2.9*255/5 = 148
So how do you use an analog port? First make sure your sensor output does not exceed your digital logic voltage (usually 0V -> 5V>. Then plug that output directly to the analog port.
This bit range could also be seen as a resolution. Higher resolutions mean higher accuracy, but occasionally can mean slower processing and more succeptability to noise. For example, suppose you had a 3 bit controller which has a range of 2^3=8. Then you have a distance sensor that outputed a number 0->7 (a total of 8> that represents the distance between your robot and the wall. If your sensor can see only 8 feet, then you get a resolution of 1 bit per foot (8 resolution / 8 feet = 1>. But then suppose you have an 8 bit controller, you would get
256/8=32 ~ 1 bit per centimeter - way more accurate and useful! With the 3 bit controller, you could not tell the difference between 1 inch and 11 inches.
Digital I/O Ports Digital ports are like analog ports, but with only 1 bit (2^1=2> hence a resolution of 2 - on and off.
Digital ports obviously for that reason are rarely used for sensors, except for maybe on/off switches . . . What they are mostly used for is signal output. You can use them to control motors or led's or just about anything. Send a high 5V signal
to turn something on, or a low 0V to turn something off. Or if you want to have an LED at only half brightness, or a motor at half speed, send a square wave. Square waves are like turning something on and off so fast that its almost like sending out
an analog voltage of your choice. Neat, huh?
This is an example of a square wave for PWM:
These squarewaves are called PWM, short for pulse width modulation. They are most often used for controlling servos or DC motor H-Bridges.
Also a quick side note, analog ports can be used as digital ports.
Serial Communication, RS232, UART A serial connection on your microcontroller is very useful for communication. You can use
it to program your controller from a computer, use it to output data from your controller to your computer (great for debugging>, or even use it to operate other electronics such as digital video cameras. Usually the microcontroller would require an external IC to handle everything, such as an RS232.
Timers A timer is the method by which the microcontroller measures the passing of time - such as for a clock, sonar, a pause/wait command, timer interrupts, etc.
Motor Driver To run a DC motor you need to either have an H-Bridge or a Motor Driver IC. The IC is great for small robots that do not exceed 1 or 2 amps per motor and the rated motor voltage is not higher than about 12V. The homemade H-Bridge would need to be used if you wanted to exceed those specs. There are a few H-Bridge controllers commercially available to buy, but usually they are way too expensive and are designed
for battlebot type robots. The IC is small, very cheap, and can usually handle two motors. I highly recommend opting for the IC. Also, do not forget to put a heatsink onto the motordriver. Motordrivers give off pretty fireworks when they explode from overheating =>
Another interesting note, you can stack IC's in parallel to double the allowable current and heat dissipation.
Theoretically you can stack as many as you want, as long as the current is high enough to still operate the logic of the IC. This works for voltage regulators too.
Output Indicators Im referring to anything that can be used for debugging by communicating information to you. LED's, buzzers, LCD screens, anything that gives output. The better the indicator, the easier the debugging. The best indicator is to have your robot tethered and print or data log sensor and
action data to your computer, but it isn't always possible to have your robot tethered.
Programming Languages The lowest form of programming languages
is the machine language. Microcontrollers need to be programmed with this.
These higher languages would then be compiled automatically
into a machine language, which then you can upload into your robot. Probably the easiest language to learn would be BASIC, with a name true to itself. The BASIC Stamp microcontroller
uses that language. But BASIC has its limitations, so if you have any programming experience at all, I recommend you program in C. This language was the precurser to C++, so if you can already program in C++, it should be really simple for you to learn. What complicates this is that there is no standard to programming microcontrollers. Each has its own features, its own language, its own compiler, and its own uploading to the controller method.
This is why I do not go into too much detail because there are too many options out there to talk about. The support documents that come with the controllers should answer your specific
questions. Also, if you decide to use a PIC, understand that the compiler program (at least the good ones> can cost hundred of dollars. Most microcontrollers also require a special interface device between your computer and the chip for programming which could also cost from $10-$40.
Costs With possibly the exception of DC motors, the microcontroller is the most expensive part of your robot. There is just no escaping the costs, especially for the beginner. But remember, after buying all this for your first robot, you do not need to buy any of it again as you can reuse everything. So here is the breakdown of costs. The chip itself, without augmentation, would only cost dollars. But understand the chip is useless without the augmentation, so you would need to do it yourself if you do not buy it already augmented. This could potentially cost just as much with the augmentation, and could cause you many frustrations.
If however you are more experienced (and for some odd reason still reading this>, you can customize your own circuit to do exactly what you want. Why have a motordriver when you are only using servos anyway? If you decide to buy an augmented MCU, the cost will range from about $50-$150. To compile your program, you would need to get special compiling software. Atmel and BASIC Stamps have free compilers. PIC's however have fairly expensive compilers. There are some free ones available online, but they are of poor quality in my opinion. CCSC PIC C compiler is about $125, but I think it is worth getting if you are going to use PIC's.
You will also need an uploader to transfer the program from your computer to the chip. This generally requires more special software and a special interface device. The Cerebellum PIC based controller has this built in which is really nice and convienent, but for any others expect to spend from $10-$40. People often opt to just make their own as the circuit isnt too complicated.
As a prototyper, what you probably want most is a MCU
development board. These augmented microcontrollers are
designed for the prototyper in mind. To find these augmented
MCU's, do a search for 'pic development board,' 'atmel
development board,' 'stamp development board,' etc.
单片机的介绍
什么是单片机? 正如它们的名字所说的那样。今天,它们可以被发现几乎在任何复杂电子设备中-比如用便携式音乐设备来洗你车上的机械装置。他们是可编程、便宜、微小,可以处理滥用,基本不需要消耗多少能量,现在已经有如此多的种类来适应每一个需要。这对于机器人来说非常有益-像小的可以负担一切任务的计算机,你可以把命令分配给你的机器人。
不断发展的微控制器及其发展格局
在一个纯粹意义上,它是一个微控制器IC<集成电路，或者带有引脚的黑色芯片）。然而它很容易添加更多的外部组件,如电压调节,电容,LED,汽车司机、时间晶体、RS232等基本IC。形式上,这被称作加强型微控制器。但在现实中,大部分人还是称其为微控制器即使其增加了不少附件。其他简称将其称为不受控制的和微控制器单元(MCU>。通常,我所说的微控制器，我的意思是说增强型微控制器。
作为一个初学者可能最佳的就是购买加强微控制器。为什么呢? 因为他们拥有非常吸引人的设计并且可以装配组合和调试后为你服务。他们还常常与高科技提供技术支持,样本代码和大量社会上的人会来协助你做好这些。我国微控制
器领域展示了更多流行机型你都可以买到。根据不同的特点，他们的费用往往
从30美元到150美元不等。这将给你一个很好的介绍,单片机编程不必与所有
技术有关的东西联系。
从长远看来你应该建立你自己的微控制器厂以便于你可以更好的理解它们。去
创造自己的优势，前提是它可能会花你10-30美元。
在得到一个完整的增广板和自己不断完善它之间我们称其为一个发展空间。这些增广板在完善之前仅仅是一些后续工作的基础。它们是被设计为原型的测
试并且这种新思想传播的非常迅速。它们具有代表性的成本在15美元和40美
元之间。
什么是IC？
有一个巨大的多种微控制器的市场,但我要仔细检查几个常见的功能,这样你会发现对你的机器人有用的项目。
对机器人而言，时间是比其他任何都要重要的一个特征,是一个单片机的I / O 端口。输入端是用来考虑在传感器的数据,而输出是用来发送指令到外部硬件,如伺服系统。有两种类型的I / O端口,模拟的和数字的。
模拟输入端口
模拟端口需要连接传感器和你的机器人。也被称为一个模拟/数字转换器(ADC>,他们接收模拟信号并把它们转化成一个数字号码在一定数值的范围。
那么什么是模拟信号呢?模拟信号是一个在一定范围内连续变化的电压,为一些典型的传感器所共有。然而计算机仅能运作的数字领域仅有0和1。那么,单片机怎么控制一种模拟信号转换为数字信号呢?
首先,模拟测量一段时间后传递的一个预定义数据。在每个时间段内,电压记录成一个数字。这个号码然后定义了信号的0和1的如图所示:
数字信号较模拟信号的优势是,数字数字在消除背景噪音方面更有优势。手机逐渐数字化的今天,虽然这个数字信号是一种比模拟信号没有多少代表性的信号,但是也不能降低其作用因为计算机可以恢复损坏的数字信号。这允许一个清晰的输出信号与你的操作管理器或者其他装置。MP3的,通常都是数位也在128 kbps编码。高比特率明显意味着更高的质量,因为他们更好地代表了模拟信号。但更高的比特率也需要更多的内存和处理能力。
现在的微控制器大多数都是八位的,这意味着他们会在0~256这个范围波动(2 ^ 8 = 256>。有一些是10位,12位,甚至是32位,但是当你需要增加精密度时你也需要一个更快的处理器。
这些字节意味着ADC的什么呢?例如,假设一个传感器读到一个8位ADC 0V。这将给你一个数字输出 0。5伏的将是255。现在,假设一个传感器给一种输出2.9伏特, ADC的输出会是什么呢?
这道数学题计算如下:
2.9V / 5V = X / 255
255/5 X = 2.9 * = 148
因此你应该怎么使用模拟端口呢?首先确保你的传感器输出不超过你的数字逻辑电压范围(通常0V- > 5伏>。然后插头,输出直接插入模拟端口。
这个位的范围也可以被看作是一个分辨率。更高的分辨率意味着更高的精度,但偶尔也意味着更多的是处理缓慢和较强的抗噪能力。例如,假设你有一个
3位控制器,其中有一个范围为2 ^ 3 = 8。那么你有一个距离感应器,输出一个数字0 - > 7(一共有8>,代表你的机器人与墙之间的距离。如果你的传感器只
能看到8英尺,然后得到分辨率为1比特每英尺(8 / 8英尺的分辨率= 1>。但后来假设你有一个八位元的控制器,你将会得到256/8 = 32 ~ 1比特/厘M——这种方法更加准确和有用!用一个3位的控制器,你分辨不出1英寸和11英寸。
数字I / O口
就像模拟端口数字端口,但只有1比特(2 ^ 1 = 2>分辨率为2的开关。因为这个原因,数字端口显然很少用于传感器,或许除了开/关转换…他们大多数主要用于信号的输出。你可以用它们来控制马达或者led或任何事。发出一个高于5V的信号,或者低于0V时关闭某些东西。或者,如果你想拥有一个LED一半的亮度,或者发动机处于半速,送出一个方波。这些方波就像控制开关变换地如此之快,它几乎像为你的选择发出一种模拟电压。没有干扰的信号,嗯?
这是一种典型的方波为PWM:
这些方波被称为PWM,短脉冲宽度调制。他们是最常用的伺服控制H-Bridges或直流电机。
附注一点,也可以作为模拟端口和数字端口。
RS232、UART串行通信
在你的单片机串行连接进行交流沟通是非常有用的!你可以用它来操纵你的控制器,使用它从电脑控制器输出数据从你的计算机(大胆的调试>,或者甚至是用它来操作其他电子元件如数码摄像机。通常在单片机将需要外部的IC来处理一切,如RS232。
时钟
一个定时器是采用单片机控制时间的流逝-例如,一个时钟,声纳,一个暂停
/等待命令、定时器中断等。
电机驱动
直流电机运行时需要有一个H-Bridge或电机驱动集成电路。集成电路是伟大的
为小机器人不超过1或2每台电机的额定电流,电机电压不高于大约12伏。自制的
H-Bridge会需要如果想超过那些规格。有些H-Bridge控制器市场上可很容易买到,但通常它们特别贵,而且都是专为一些士兵机器人。集成电路很小,非常便宜,通常可以应付两电机。我高度推荐选择集成电路。同时,不要忘了加散热器到驱动器<电机驱动时因过热发出漂亮的火花会发生爆炸>。
另一个有趣的记录,你可以叠加集成电路在电流和散热条件都满足时。理论上你可以堆叠直到你想要的,只要是当前高到仍然满足采用逻辑集成电路。这部作品也可以作为电压调节器。
产出指标
我指的是任何事情都可能被用于调试通过给你的交流信息。LED、蜂音器、LCD液晶屏幕,任何输出的工具。越好越易于调试。最好指标是将你的机器人活动范围打印或者以数据日志通过传感器发送到你的计算机,但并不可能总是操控你的机器人。
编程语言
最低形式的编程语言是机器语言。微控制器需要通过编程来实现某些功能。
这些更高的语言会自动转换成机器语言编译,然后您可以上传进你的机器人。可能最简单的语言将是最基本的使用一个真实名称。最基本的单片机应用的就是这那种语言。但基本语言也有其局限性,因此,如果你有任何编程经验,我建议你在C语言程序,这是作为c++的前驱,所以如果你已经能用c++程序,它应该是相当的简单当你去学习时。复杂的是没有规范的微控制器程序。每种语言都有其自身的特点,它自己的语言、自己的编译器,和它自己的上传到控制器的方法。
这就是为什么我不去追究过多的细节,因为有太多的选择可谈。支撑文件的控制器可以解答你的具体问题。而且,如果你决定要用一张图片,理解编译器程序(至少会用>需要花费100美元。大多数微控制器在你的计算机和芯片编程过程中也需要配备一种特殊的接口设备,这也可能话费你 10 - 40美元。
成本
除了可能的直流电机,单片机是你的机器人里最昂贵的一部分。这世上只有一个不争的成本,特别是对于初学者的。但是记住,买完这一切为你的第一个机器人,你不需要再次购买任何东西,你就能重复使用所有的一切。所以这里是分
解的成本。该芯片自身,没有扩增,只会花费美元。但是,你要明白该芯片没有了扩展功能将毫无用处,因此你会需要自己去做如果你不买它。这可能费用差不多与扩展其功能,你也有可能导致很多挫折。
如果你比我更有经验(因为一些奇怪理由还阅读这个>,你可以制作自己想要做的电路。为什么有电动驱动器当你只使用伺服程度时?如果你决定买一条增量MCU、成本的范围约50美元- 150美元。编译你的程序,你将需要得到特别编制的软件。Atmel和BASIC有免费编译器。然而PIC有相当昂贵的编译器。有一些免费的网上可查的,但是在我看来他们是质量低劣的。CCSC PIC的C编译器大约125美元,但我认为那不值得得到如果你要使用PIC的。
你也需要一个从你的电脑晶片上传转让程序的上传者。这通常需要更特殊的软件和一个特别的接口装置。电脑PIC基础控制器具有这项功能并且做的非常好且方便,但任何其他的要花上10- 40美元。人们往往选择他们自己的设计使得电路不是太复杂。
作为一个模板,你可能需要最多的是单片机开发板。这些增广微控制器是模板的核心科技。为了找到这些增量MCU,做了搜索型的pic开发板,“atmel开发板,“邮票开发板,'等等。
单片机-英文参考文献
Structure and function of the MCS-51series Structure and function of the MCS-51series one-chip computer MCS-51is a name of a piece of one-chip computer series which Intel Company produces.This company introduced8top-grade one-chip computers of MCS-51series in1980after introducing8one-chip computers of MCS-48series in1976.It belong to a lot of kinds this line of one-chip computer the chips have,such as8051,8031,8751, 80C51BH,80C31BH,etc.,their basic composition,basic performance and instruction system are all the same.8051daily representatives-51serial one-chip computers. An one-chip computer system is made up of several following parts:(1)One microprocessor of8(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 one-chip computers,such as8031, 8032,80C,etc..(4)Four8run side by side I/O interface P0four 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 computer.(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 one-chip computer or one-chip computer and serial communication of computer to use for.(8)Stretch oscillator and clock produce circuit,quartz crystal finely tune electric capacity need outer.Allow oscillation frequency as12megahertas now at most.Every the above-mentioned part was joined through the inside data bus.Among them,CPU is a core of the one-chip computer,it is the control of the computer and command centre,made up of such parts as arithmetic unit and controller,etc..The arithmetic unit can carry on8persons of arithmetic operation and unit ALU of logic operation while including one,the1 storing device temporarilies of8,storing device2temporarily,8's accumulation
本科毕业论文内部控制外文文献翻译完整版中英对照
A Clear Look at Internal Controls: Theory and Concepts Hammed Arad (Philae) Department of accounting, Islamic Azad University, Hamadan, Iran Barak Jamshedy-Navid Faculty Member of Islamic Azad University, Kerman-shah, Iran Abstract: internal control is an accounting procedure or system designed to promote efficiency or assure the implementation of a policy or safeguard assets or avoid fraud and error. Internal Control is a major part of managing an organization. It comprises the plans, methods, and procedures used to meet missions, goals, and objectives and, in doing so, support performance-based management. Internal Control which is equal with management control helps managers achieve desired results through effective stewardship of resources. Internal controls should reduce the risks associated with undetected errors or irregularities, but designing and establishing effective internal controls is not a simple task and cannot be accomplished through a short set of quick fixes. In this paper the concepts of internal controls and different aspects of internal controls are discussed. Keywords: Internal Control, management controls, Control Environment, Control Activities, Monitoring 1. Introduction The necessity of control in new variable business environment is not latent for any person and management as a response factor for stockholders and another should implement a great control over his/her organization. Control is the activity of managing or exerting control over something. he emergence and development of systematic thoughts in recent decade required a new attention to business resource and control over this wealth. One of the hot topic a bout controls over business resource is analyzing the cost-benefit of each control. Internal Controls serve as the first line of defense in safeguarding assets and preventing and detecting errors and fraud. We can say Internal control is a whole system of controls financial and otherwise, established by the management for the smooth running of business; it includes internal cheek, internal audit and other forms of controls. COSO describe Internal Control as follow. Internal controls are the methods employed to help ensure the achievement of an objective. In accounting and organizational theory, Internal control is defined as a process effected by an organization's structure, work and authority flows, people and management information systems, designed to help the organization accomplish specific goals or objectives. It is a means by which an organization's resources are directed, monitored, and measured. It plays an important role in preventing and detecting fraud and protecting the organization's resources, both physical (e.g., machinery and property) and intangible (e.g., reputation or intellectual property such as trademarks). At the organizational level, internal control objectives relate to the reliability of financial reporting, timely feedback on the achievement of operational or strategic goals, and compliance with laws and regulations. At the specific transaction level, internal control refers to the actions taken to achieve a specific objective (e.g., how to ensure the organization's payments to third parties are for valid services rendered.) Internal control
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.
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
会计内部控制中英文对照外文翻译文献
会计内部控制中英文对照外文翻译文献(文档含英文原文和中文翻译) 内部控制系统披露—一种可替代的管理机制 根据代理理论，各种治理机制减少了投资者和管理者之间的代理问题（Jensen and Meckling，1976； Gillan，2006）。传统上，治理机制已经被认定为内部或外部的。内部机制包括董事会及其作用、结构和组成（Fama，1980；Fama and Jensen，1983），管理股权(Jensen and Meckling，1976)和激励措施，起监督作用的大股东(Demsetz and Lehn，1985)，内部控制系统(Bushman and Smith，2001)，规章制度和章程条款(反收购措施)和使用的债务融资（杰森，1993）。外部控制是由公司控制权市场(Grossman and Hart,1980)、劳动力管理市场（Fama,1980）和产品市场（哈特,1983）施加的控制。 各种各样的金融丑闻，动摇了世界各地的投资者，公司治理最佳实践方式特别强调了内部控制系统在公司治理中起到的重要作用。内部控制有助于通过提供保证可靠性的财务报告，和临时议会对可能会损害公司经营目标的事项进行评估和风险管理来保护投
资者的利益。这些功能已被的广泛普及内部控制系统架构设计的广泛认可，并指出了内部控制是用以促进效率，减少资产损失风险，帮助保证财务报告的可靠性和对法律法规的遵从（COSO,1992）。 尽管有其相关性，但投资者不能直接观察，因此也无法得到内部控制系统设计和发挥功能的信息，因为它们都是组织内的内在机制、活动和过程（Deumes and Knechel,2008）。 由于投资者考虑到成本维持监控管理其声称的（Jensen and Meckling，1976）,内部控制系统在管理激励信息沟通上的特性，以告知投资者内部控制系统的有效性,是当其他监控机制（该公司的股权结构和董事会）比较薄弱，从而为其提供便捷的监控（Leftwich et等, 1981）。存在的替代机制一直是人们在不同公司治理文献中争论的话题（Rediker and Seth, 1995；Fernandez and Arrondo，2005），基于威廉姆森（1983年）的替代假说认为，特定控制机制的边际作用取决于其在公司治理制度的相对重要性。 在本文中，我们认为披露内部控制系统的特点是在管理者选择的监控机制时存在一个可替代治理机制。Leftwich（1981）认为“管理者选择一个监控包，监测包的组成取决于各种监控机制的成本与效益”（P.59）。 特别是，我们重点关注内部控制系统和监控包的另外两个机制 (公司的所有权结构和董事会) 间的关系，根据有关文献（Jensen and Meckling，1976；Fernandez and Arrondo，2005；Gillan，2006）它们在管理行为监控方面发挥相关作用。我们假设认为，内部控制系统的特性取决于激励由企业的股权结构和董事会发挥监督作用。 因此,我们研究了三年间在四个不同的证券交易所上市（伦敦、巴黎、法兰克福和米兰）160家欧洲公司内部控制系统披露程度，通过利用这个国际范例,我们能够描绘出不同的体制环境的某些功能。 我们发现证据表明内部控制系统披露代替了监测方面所发挥的作用与所有制结构、制度所有权、在董事会上独立董事比例和会计审计委员会的专家成员的比率相关。 我们再加上通过内部会计控制的披露所发挥的管理作用，采用以往文献的完整披露架构，使我们能够详细地从内容和信息管理的程度上内制披露上进行交流。而公司治理的最佳做法要求披露内部控制系统的特性，他们没有提供管理应该披露和披露程度的指令。这样的管理缺乏指示使内部控制系统存在随意性。 本文提供了实证支持威廉姆森（1983年成立）在不同的治理机制下的替代假说，它有相应的政策含义。虽然大多数公司治理研究考虑一个互补的披露机制管理采用强化公
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
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
毕业设计_英语专业论文外文翻译
1. Introduction America is one of the countries that speak English. Because of the special North American culture, developing history and the social environment, American English has formed its certain unique forms and the meaning. Then it turned into American English that has the special features of the United States. American English which sometimes also called United English or U.S English is the form of the English language that used widely in the United States .As the rapid development of American economy, and its steady position and strong power in the world, American English has become more and more widely used. As in 2005, more than two-thirds of English native speakers use various forms of American English. The philologists of the United States had divided the English of the United States into four major types: “America n creating”; “Old words given the new meaning”; “Words that eliminated by English”;“The phonetic foreign phrases and the languages that are not from the English immigrates”[1]. Compared to the other languages, American English is much simple on word spelling, usage and grammar, and it is one of the reasons that American English is so popular in the world. The thesis analyzes the differences between American English and British English. With the main part, it deals with the development of American English, its peculiarities compared to that of British English, its causes and tendency. 2. Analyses the Differences As we English learners, when we learning English in our junior or senior school, we already came across some words that have different spellings, different pronunciations or different expressions, which can be represented by following contrasted words: spellings in "color" vs. "colour"; pronunciations in "sec-re-ta-ry" vs. "sec-re-try";
审计学内部控制中英文对照外文翻译文献
中英文翻译 内部控制爆炸① 摘要：Power的1997版书以审计社会为主题的探讨使得审计活动在联合王国（英国）和北美得到扩散。由审计爆炸一同带动的是内部控制制度的兴起。审计已经从审计结果转向审计制度和内部控制，它已然成为公众对公司治理和审计监管政策的辩论主题。Power表示对什么是有效的内部控制各方说法不一。本人对内部控制研究方面有一个合理的解释。内部控制对非常不同概念的各个领域的会计进行探究，并研究如何控制不同水平的组织。因此，内部控制研究的各类之间的交叉影响是有限的，而且，许多内部会计控制是研究是再更宽广的公司治理问题的背景下进行的。所以，许多有关内部控制制度对公司治理的价值观点扔需要进行研究。 关键词：机构理论；公司治理；外部审计；内部审计；内部控制制度；管理控制 1 概述 Power的1997版书以审计社会为主题的探讨使得审计活动在联合王国（英国）和北美得到扩散。由审计爆炸一同带动的是内部控制制度的兴起。审计已经从审计结果转向审 ①Maastricht Accounting and Auditing Research and Education Center (MARC), Faculty of Economics and Business Administration, Universiteit Maastricht, P.O. Box 616, 6200 MD Maastricht, The Netherlands s.maijoor@marc.unimaas.nl Fax: 31-43-3884876 Tel: 31-43-3883783
计制度和内部控制，它已然成为公众对公司治理和审计监管政策的辩论主题。例如，在最近的对于欧洲联盟内外部审计服务的内部市场形成的辩论中，监管建议建立关于内部控制和内部审计制度。虽然对有关内部控制的价值期望高，但Power表示对什么是有效的内部控制各方说法不一。本人对内部控制研究方面有一个合理的解释。内部控制是对非常不同概念的各个领域的会计进行探究，并研究如何控制不同水平的组织。因此，内部控制研究的各类之间的交叉影响是有限的，而且，许多内部会计控制是研究是再更宽广的公司治理问题的背景下进行的。所以，许多有关内部控制制度对公司治理的价值观点扔需要进行研究。 在审计和公司治理的公共政策辩论中，内部控制的概念越来越得到重视。公共越来越关注内部控制，令人对power在1997年英国和北美的书中的审计社会的现状有所信服。此书的主题是在Anglo-Saxon经济体的审计活动：审计爆炸的扩散。Power表示，联合开发与审计爆炸带动了内部控制制度兴起。增加监管问责制是公众对审计和公司治理政策辩论机构内部控制系统的一部分。然而Power注意到，尽管公众对内部控制的关注度迅速增加，内部控制的概念还是很模糊。他支出，内部控制是什么，内部控制的有效性的界定是内部控制的最基本问题。 本文讨论研究内部控制的兴起，认为内部控制的研究也有一些潜在的问题。首先，在以往的研究中，长期的内部控制涵盖完全不同的概念。其次，有关的内部控制研究机构的规模是有限的，要从孤立的学科进行交叉使用得到结果很难。因此，内部控制是尚未独立的研究范畴。最后，以往的对内部控制的研究没有彻底解决在审计和公司治理的公共政策辩论中谈到的内部控制有关问题。假设的内部控制、财务报告和公司治理的基本关系也没有被证实。 本文解构如下：在开始对内部控制进行研究和讨论之前，先介绍了两个主要的，在Power1997的书中所提出的发展：第一部分讨论了审计爆炸，第二部分讨论了内部控制的崛起。两者也讲被从欧盟的角度评论。第三部分讨论了什么是内部控制，并从会计研究的三个主要观点出发，研究内部控制制度。第四部分确定了内部控制和公司治理的公共政策辩论所承担的四个基本关系，并讨论之前的相关研究。最后一节提供了一个总结和结论。 2 内部控制的崛起 不论是否存在审计爆炸，Power1997和1998在审计中变得越来越重要。根据Power （1997年83爷），因为内部控制系统的可审计假设使得审计爆炸成为可能。根据更具体
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，