【正文】 外部時(shí)鐘源時(shí)，此引腳可懸空，此時(shí)XTAL2實(shí)際將XTAL1輸入的時(shí)鐘進(jìn)行輸出、VCC：電源正極GND：電源負(fù)極，接地(1)關(guān)于復(fù)位電路：時(shí)鐘頻率低于12MHz時(shí)，可以不用C1，R1接1K電阻到地時(shí)鐘頻率高于12MHz時(shí)，建議使用第二復(fù)位功能腳(2)關(guān)于晶振電路：如果使用內(nèi)部R/C振蕩器時(shí)鐘，XTAL1和XTAL2腳懸浮。對(duì)外接電容的值雖然沒(méi)有嚴(yán)格的要求，但是電容的大小會(huì)影響振蕩器頻率的高低、振蕩器的穩(wěn)定性和起振的快速性。555電路，也稱(chēng)555芯片電路，是一種中規(guī)模集成電路。 電容測(cè)量系統(tǒng)按鍵電路按鍵是實(shí)現(xiàn)人機(jī)對(duì)話的比較直觀的接口，可以通過(guò)按鍵實(shí)現(xiàn)人們想讓單片機(jī)做的不同的工作。本次設(shè)計(jì)中應(yīng)用的電路是直接反饋型無(wú)穩(wěn)類(lèi)電路。第2腳：VDD接5V正電源。指令1：清顯示，指令碼01H,光標(biāo)復(fù)位到地址00H位置指令2：光標(biāo)復(fù)位，光標(biāo)返回到地址00H指令3：光標(biāo)和顯示模式設(shè)置I/D：光標(biāo)移動(dòng)方向，高電平右移，低電平左移S:屏幕上所有文字是否左移或者右移。從書(shū)本上學(xué)不會(huì)設(shè)計(jì)，只能經(jīng)過(guò)實(shí)踐，通過(guò)對(duì)實(shí)際系統(tǒng)的研究和實(shí)踐才能學(xué)會(huì)。作為還在學(xué)生階段的我們，用匯編語(yǔ)言進(jìn)行編程對(duì)我們理解單片機(jī)的內(nèi)部結(jié)構(gòu)、資源都有很好的幫助，但是編程在以后的實(shí)際工作中將會(huì)大大簡(jiǎn)化自己的工作。我們?nèi)〔煌碾娮柚?，就得到不同的電容測(cè)量的量程。開(kāi)始的首先檢測(cè)一下是否為忙。尤其是使用C語(yǔ)言編寫(xiě)程序[15]的時(shí)候更是要注釋?zhuān)驗(yàn)镃語(yǔ)言是一門(mén)比較高級(jí)的語(yǔ)言，C語(yǔ)言比較的煩瑣。系統(tǒng)的軟件部分是系統(tǒng)實(shí)現(xiàn)功能的關(guān)鍵，軟件部分是在Keil51的平臺(tái)上使用是C語(yǔ)言編寫(xiě)程序。還要特別感謝我的同學(xué)，正是與他們?cè)谠S多問(wèn)題上的交流、討論，在他們的幫助之下，我的論文才得以順利完成。 Therefore, the development of dedicated single chip SOC trend of the natural form. As the microelectronics, IC design, EDA tools development, application system based on MCU SOC design have greater development. Therefore, the understanding of the microcontroller chip microputer can be, extended to the singlechip microcontroller applications.MCU applications SCM now permeate all areas of our lives, which is almost difficult to find traces of the field without SCM. Missile navigation equipment, aircraft, all types of instrument control, puter network munications and data transmission, industrial automation, realtime process control and data processing, extensive use of various smart IC card, civilian luxury car security system, video recorder, camera, fully automatic washing machine control, and programcontrolled toys, electronic pet, etc., which are inseparable from the microcontroller. Not to mention the area of robot control, intelligent instruments, medical equipment was. Therefore, the MCU learning, development and application of the large number of puter applications and intelligent control of the scientists, engineers. SCM is widely used in instruments and meters, household appliances, medical equipment, aerospace, specialized equipment, intelligent management and process control fields, roughly divided into the following several areas:1. In the application of Intelligent Instruments SCM has a small size, low power consumption, controlling function, expansion flexibility, the advantages of miniaturization and ease of use, widely used instrument, bining different types of sensors can be realized Zhuru voltage, power, frequency, humidity, temperature, flow, speed, thickness, angle, length, hardness, elemental, physical pressure measurement. SCM makes use of digital instruments, intelligence, miniaturization, and functionality than electronic or digital circuits more powerful. Such as precision measuring equipment (power meter, oscilloscope, various analytical instrument).2. In the industrial control application With the MCU can constitute a variety of control systems, data acquisition system. Such as factory assembly line of intelligent control3. In Household Appliances Can be said that the appliances are basically using SCM, praise from the electric rice, washing machines, refrigerators, air conditioners, color TV, and other audio video equipment, to the electronic weighing equipment, varied, and omnipresent. 4. In the field of puter networks and munications applications MCU general with modern munication interface, can be easy with the puter data munication, networking and munications in puter applications between devices had excellent material conditions, are basically all munication equipment to achieve a controlled by MCU from mobile phone, telephone, miniprogramcontrolled switchboards, building automated munications call system, train radio munication, to the daily work can be seen everywhere in the mobile phones, trunked mobile radio, walkietalkies, etc..5. Microputer in the field of medical device applications SCM in the use of medical devices is also quite extensive, such as medical respirator, the various analyzers, monitors, ultrasound diagnostic equipment and hospital beds, etc. call system. 6. In a variety of major appliances in the modular applications Designed to achieve some special single specific function to be modular in a variety of circuit applications, without requiring the use of personnel to understand its internal structure. If music integrated single chip, seemingly simple function, miniature electronic chip in the net (the principle is different from the tape machine), you need a puter similar to the principle of the plex. Such as: music signal to digital form stored in memory (like ROM), read by the microcontroller, analog music into electrical signals (similar to the sound card). In large circuits, modular applications that greatly reduce the volume, simplifies the circuit and reduce the damage, error rate, but also easy to replace. 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 learningMCU 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 surpr