【正文】 igned addresses to use, the allocation of addresses is of course to give the form of electrical signals, and because memory cells are more so for address the allocation of more lines, these lines were known as the address bus. Second, data, address, mand: The reason why these three together, because these three are the essence is the same figure, or are a string of39。s first four microprocessor, The Intel pany hoff successfully developed the world39。s of dedicated processor, whereas normal type exfactory price dropped to $1, the highestprofile [1] type was only ten dollars. Contemporary SCM system no longer only in LuoJi environment, development and use of special embedded operating system is widely used in the whole range of singlechip microputer. While in as a handheld puters and mobile phones key processing of highend microcontroller even can directly use the special Windows and Linux operating system. Singlechip processor more than dedicated suitable for use with embedded system, so it has gained the most applications. In fact microcontroller is the world largest number of the puter. Modern human life that are used in almost every pieces of electronic and mechanical products will be integrated have microcontroller. Mobile, telephone, calculator, home appliances, electronic toys, PDA and mouse and so on puter accessories are equipped with 12 department microcontroller. The PCS in also will affect many microputer in the work. Cars equipped with more than 40 department general singlechip microputer, plex industrial control system even there may be hundreds microputer in working at the same time! The number of MCU is not only far more than PCS and other calculation bined, and even more than the number of human beings. SCM is also called monolithic micro controller, it is not plete a logic function chips, but it is a puter system integration to a chip. The puter equivalent of a micro puter, and pared, microcontroller lack only the I/O devices. General speaking: a chip became a puter. Its pact size, light quality, cheap, for learning, application and development provides the convenience. Meanwhile, learning to use a single chip puter is knowledge of puter principle and structure of the best choice. SCM internal also use and puter functions similar module, such as CPU, memory, parallel bus and hard disk storage device functions are the same, the difference is its relative performance all these parts of our home puter weak, but the price is much lower, usually less than 10 yuan can... Use it to do some control electric appliance category is not very plicated work is sufficient. We use now roller washing machine, smoke exhaust hood, VCD and so on the home appliance inside can see the figure! ... It was mainly used as a core part of the control part. It is a kind of online realtime control puter, online is site control, need is strong antijamming ability, low cost, this also is and offline puter (such as household PC) the main difference. A single chip puter is by program running, and can be modified. Through the different program realization of different function, especially the unique some special function, this is another device needs to spend effort can do that, while some others are great effort also hard to do. One is not very plicated function if use in the United States during the 1950s development of 74 series, or from the 1960s CD4000 series these pure hardware to fix words, circuit must be a large piece of PCB board! But if if use American 1970s success on the market series microcontroller, and the results will be difference! Just because of single chip through your programming can achieve high intelligence, high efficiency and high reliability. Due to cost is sensitive microcontroller, so, at present, the dominant software or lowest assembly language, it is besides the binary machine code above the lowest language, since so lowlevel why use? Many senior language has reached the level of visual programming is why not? The reason is very simple, that is no home puter microcontroller as the CPU, also did not like hard disk that mass storage device. A visual small programs written in highlevel languages inside has even a button, also can achieve dozens of K size! For household PC hard disk speaking nothing, but the SCM speaking is unacceptable. Microputer in hardware resources utilization must high to just go, so assembly although original but still in use large. The same way, if the giant puter operating system and application software got home PC came running, household PC is also cannot bear. Can say, the twentieth century across the three electricity age, namely the age of electricity, electronic era and now has entered the puter era. However, this kind of puter, usually refers to the personal puter, the abbreviation PCS. It consists of host, keyboard, display etc. And those puter, most people do not so familiar with. This puter is intelligence gives all kinds of mechanical SCM (also called micro controller). As the name suggests, the puter is minimal systems only took a piece of integrated circuits, simple operation and control can be carried out. Because of its small size, usually hidden in the accused of mechanical stomach. It in the whole device, plays the role of like the human mind, it went wrong, the whole device broke down. Now, this SCM use field has been widely, such as intelligent instruments, realtime control, munication equipment, navigation system, household electric appliances, etc. Various products once using singlechip microputer, can have the effect that product upgrading, often in product specialty bariatric adjectives intelligent, such as intelligent washing machines etc. Now some factories technicians or other leisure electronic developers out some of the products, not the circuits are too plex, is functional too