【正文】 39。advanced post out backward first out 39。this unit , and in 0000 39。, the process is always from the 000039。s instructions, and when the MCU execution to the instruction, the also make into a high, but users will not do so because this is usually will cause the system to collapse.Fourth, the program39。not39。no39。not as a generalpurpose I / O port use39。139。0 39。7. Microcontroller in the application field of automotive equipment SCM in automotive electronics is widely used, such as a vehicle engine controller, CAN busbased Intelligent Electronic Control Engine, GPS navigation system, abs antilock 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.Application of six important part of learning MCU learning an important part of the six applications 1, Bus: We know that a circuit is always made by the devices connected by wires, in analog circuits, the connection does not bee a problem because the device is a serial relationship between the general, the device is not much connection between the , but the puter is not the same circuit, it is a microprocessor core, the device must be connected with the microprocessor, the device must be coordination between, so they need to connect on a lot, as if still analog circuit like the microprocessor and devices in the connection between the individual, the number of lines will be a little more surprising, therefore the introduction of the microprocessor bus 概念 Zhong Each device Gongtong access connections, all devices 8 Shuju line all received eight public online, that is the equivalent of all devices together in parallel, but only this does not work, if there are two devices send data at the same time, a 0, a 1, then, whether the receiver received what is it? This situation is not allowed, so to be controlled by controlling the line, timesharing the device to work at any time only one device to send data (which can have multiple devices to receive both). Device39。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 forget Intel and Philips in History. Embedded SystemsEmbedded 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! 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 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 with the United States developed 74 series, or the 6039。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 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。28MCU DescriptionMCU Description SCM is also known as microcontroller (Microcontroller Unit), monly used letters of the acronym MCU 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 Z80 is the first designed in accordance with this idea processor, then on the development of microcontroller and dedicated processors have parted ways.Are 8bit 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 16bit 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, 32bit microcontroller quickly replace highend 16bit MCU status and enter the mainstream market. The traditional 8bit microcontroller performance have been the rapid increase capacity increase pared to 80 the number of times. Currently, highend 32bit microcontroller clocked over 300MHz, the performance catching the mid9039。s largest puter. 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 puters