【正文】 這一系統(tǒng)的單片機系統(tǒng)直到現(xiàn)在還在廣泛使用。而傳統(tǒng)的 8 位單片機的性能也得到了飛速提高，處理能力比起 80年代提高了數(shù)百倍。 單片機比專用處理器更適合應用于 嵌入式系統(tǒng) ，因此它得到了最多的應用。而個人電腦中也會有為數(shù)不少的單片機在工作。概括的講：一塊芯片就成了一臺計算機。我們現(xiàn)在用的全自動滾筒洗衣機、排煙罩、 VCD 等等的家電里面都可以看到它的身影！ ......它主要是作為控制部分的核心部件。一個不是很復雜的功能要是用美國 50年代開發(fā)的 74系列，或者 60年代的 CD4000 系列這些純。 單片機芯片 單片機是靠程序運行的，并且可以修改。同時，學習使用單片機是了解計算機原理與結構的最佳選擇。 單片機又稱單片微控制器 ,它不是完成某一個邏輯功能的芯片 ,而是把一個計算機系統(tǒng)集成到一個芯片上。現(xiàn)代人類生活中所用的幾乎每件電子和機械產(chǎn)品中都會集成有單片機。當代單片機系統(tǒng)已經(jīng)不再只在裸機環(huán)境下開發(fā)和使用，大量專用的嵌入式操作系統(tǒng)被廣泛應用在全系列的單片機上。 90年代后隨著消費電子產(chǎn)品大發(fā)展，單片機技術得到了巨大提高。其中最成功的是 INTEL 的 8031，因為簡單可靠而性能不錯獲得了很大的好評。單片機由芯片內僅有 CPU 的專用 處理器 發(fā)展而來。and39。unit must be stored in a single instruction. 5, the stack: Stack is a region, is used to store data, there is no special about the region itself is a part of internal RAM, special access to its data storage and the way that the socalled 39。s implementation: Reduction in power after the 8051 microcontroller within the program counter (PC) in the value of 0000 39。 but (user) 39。 form the sequence. In other words, addresses, instructions are also data. Instruction: from single chip designer provides a number of monly used instructions with mnemonic we have a strict correspondence between the developer can not be changed by the MCU. Address: the search for MCU internal, external storage units, input and output port based on the address of the internal unit value provided by the chip designer is good, can not be changed, the external unit can be single chip developers to decide, but there are a number of address units is a must (see procedures for the implementation of the process). Third, P0 port, P2 and P3 of the second function I use: Beginners often on the P0 port, P2 and P3 port I use the second function puzzled that the second function and have a switch between the original function of the process, or have a directive, in fact, the port The second feature is automatic, do not need instructions to convert. Such as , respectively WR, RD signal, when the microchip processing machines external RAM or external I / O port, they are used as a second function, not as a generalpurpose I / O port used, so long as a A microprocessor implementation of the MOVX instruction, there will be a corresponding signal sent from the or , no prior use of mands. In fact 39。s data connection is known as the data bus, the device is called line of control all the control bus. Internal or external memory in the microcontroller and other devices have memory cells, the memory cell to be assigned addresses, you can use, distribution, of course, to address given in the form of electrical signals, and as more memory cells, so, for the address allocation The line is also more of these lines is called the address bus. Second, data, address, mand: The reason why these three together because of the nature of these three are the same the number, or are a string of 39。s with a series of successful SCM market, the result will be a drastic change! Just because you are prepared by microputer programs can achieve high intelligence, high efficiency and high reliability! As the microcontroller on the costsensitive, 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 highlevel language has reached the level of visual programming 河北工程大學 科信學院 畢業(yè)設計（外文翻譯） 4 Why is not it? The reason is simply that there is no home puter as a single chip CPU, not as hard as a mass storage device. A visualization of small highlevel language program which even if only one button, will reach tens of K of size! For the home PC39。s dedicated processor, while the average model prices fall to one . dollars, the most highend [1] model only 10 dollars. Modern SCM systems are no longer only in the development and use of bare metal environment, a large number of proprietary embedded operating system is widely used in the full range of SCM. The handheld puters and cell phones as the core processing of highend microcontroller can even use a dedicated Windows and Linux operating systems. SCM is more suitab