【正文】 信， 無線電 對講機等。如：音樂信號以數(shù)字的形式存于存儲器中（類似于 ROM），由微控制器讀出，轉化為模擬音樂電信號（類似于聲卡）。 6 The Introduce Of Single Chip Microputer SCM is also known as microcontroller (Microcontroller Unit), monly used letters of the acronym MCU that it was first 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 puter system, smaller, more easily integrated into a plex and demanding on the volume control device which. INTEL39。s with the United States developed 74 series, or the 6039。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 pany in embedded applications, its great advantage, the MCS51 singlechip microputer from the rapid development of the microcontroller. Therefore, when we look back at the path of development of embedded systems, do not fet Intel and Philips in History. Embedded Systems 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。s with a series of successful SCM market, the result will be a drastic change! 8 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 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 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 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 suitable than the specific processor used in embedded systems, so it was up to the application. In fact the number of SCM is the world39。 單片機在汽車設備領域中的應用 單片機在汽車電子中的應用非常廣泛，例如汽車中的發(fā)動機控制器，基于 CAN 總線的汽車發(fā)動機智能電子控制器， GPS 導航系統(tǒng)， abs防抱死系統(tǒng)，制動系統(tǒng)等等。 5 在各種大型電器中的模塊化應用 某些專用單片機設計用于實現(xiàn)特定功能，從而在各種 電路中進行模塊化應用，而不要求使用人員了解其內部結構。 在工業(yè)控制中的應用 用單片機可以構成形式多樣的控制系統(tǒng)、數(shù)據(jù)采集系統(tǒng)。因此，單片機的學習、開發(fā)與應用將造就一批計算機應用與智能化控制的科學家、工程師。因此，對單片機的理解可以從單片微型計算機、單片微控制器延伸到單片應用系統(tǒng)。 Philips 公司以其在嵌入式應用方面的巨大優(yōu)勢，將 MCS51 從單片微型計算機迅速發(fā)展到微控制器。 (2)MCU 即微控制器（ Micro Controller Unit）階段，主要的技術發(fā)展方向是：不斷擴展?jié)M足嵌入式應用時，對象系統(tǒng)要求的各 種外圍電路與接口電路，突顯其對象的智能化控制能力。 2 單片機歷史 單片機誕生于 20 世紀 70 年代末，經(jīng)歷了 SCM、 MCU、 SOC三大階段?，F(xiàn)在，這種單片機的使用領域已十分廣泛，如 智能儀表 、實時工控、通訊設備、導航系統(tǒng)、家用電器等。這種計算機就是把智能賦予各種機械的單片機（亦稱微控制器）。 可以說，二十世紀跨越了三個 “ 電 ” 的時代，即電氣時代、電 子時代和現(xiàn)已進入的電腦時代。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系列這些純硬件來搞定的話，電路一定是一塊大 PCB板！但是如果要是用美國 70年代成功投放市場的系列單片機，結果就會有天壤之別！只因為單片機的通過你編寫的程序可以實現(xiàn)高智能，高效率，以及高可靠性！ 由于單片機對成本是敏感的，所以目前占統(tǒng)治地