單片機作為一種微型計算機,其內(nèi)部具有一定的存儲單元(8031除外),但由于其內(nèi)部存儲單元及端口有限,很多情況下難以滿足實際需求。為此介紹一種新的擴展方法,將數(shù)據(jù)線與地址線合并使用,通過軟件控制的方法實現(xiàn)數(shù)據(jù)線與地址線功能的分時轉(zhuǎn)換,數(shù)據(jù)線不僅用于傳送數(shù)據(jù)信號,還可作為地址線、控制線,用于傳送地址信號和控制信號,從而實現(xiàn)單片機與存儲器件的有效連接。以單片機片外256KB數(shù)據(jù)存儲空間的擴展為例,通過該擴展方法,僅用10個I/O端口便可實現(xiàn),與傳統(tǒng)的擴展方法相比,可節(jié)約8個I/O端口。 Abstract: As a micro-computer,the SCM internal memory has a certain units(except8031),but because of its internal storage units and the ports are limited,in many cases it can not meet the actual demand.So we introduced a new extension method,the data line and address lines combined through software-controlled approach to realize the time-conversion functions of data lines and address lines,so the data lines not only transmited data signals,but also served as address lines and control lines to transmit address signals and control signals,in order to achieve an effective connection of microcontroller and memory chips.Take microcontroller chip with256KB of data storage space expansion as example,through this extension method,with only10I/O ports it was achieved,compared with the traditional extension methods,this method saves8I/O ports.
標簽: 單片機 P0口 數(shù)據(jù)存儲器 擴展
上傳時間: 2014-12-26
上傳用戶:adada
實時時鐘是微機保護裝置的重要部件,在討論PCF8583結(jié)構(gòu)與功能的基礎(chǔ)上,提出采用dsPIC33F系列微處理器與串行I2C時鐘PCF8583的接口設(shè)計方案,給出了相應的接口電路與軟件流程。該設(shè)計方案結(jié)構(gòu)簡單,可靠性高,開發(fā)周期短,具有一定的實用與參考價值。所設(shè)計的微機保護裝置已投入現(xiàn)場運行,效果良好。 Abstract: Real-time clock chip is an important part in microcomputer protection device.Based on discussing the structure and function of PCF8583,a new interface scheme which uses dsPIC33F microprocessor and serial clock chip(I2C)PCF8583is proposed.The method of the circuit design and the main software flow are introduced in this paper.The scheme has simple structure,higher reliability and shorter exploitation cycle,so has definite practicality or reference value.The microcomputer protection device has been put into operation with better effects.
上傳時間: 2013-11-18
上傳用戶:Thuan
針對盤山路存在的轉(zhuǎn)彎盲區(qū),即在轉(zhuǎn)彎時司機無法得知彎路對面是否有車輛通過,設(shè)計一種基于C8051F310的山路轉(zhuǎn)彎預防警示系統(tǒng)。該系統(tǒng)利用一階濾波算法檢測山路轉(zhuǎn)彎時是否有車輛通過。運用該算法可增強系統(tǒng)檢測的實時性,提高檢測機動車輛的靈敏度,同時大大減少環(huán)境溫度對檢測的干擾。試驗表明該系統(tǒng)能夠正確指示出在山路轉(zhuǎn)彎時是否有車輛通過,目前該系統(tǒng)已安裝在盤山路上,可大大減少事故的發(fā)生率。 Abstract: Aiming at passing hilly road,there is a turn blind spot.Motormen usually do not know if the passing of vehicles pass the road.So a system of defending accident on hilly road is designed,which is based on MCU C8051F310.The sys-tem uses the first-order filter algorithm to detect whether there are passing vehicles.This algorithm enhances the real-time detection and improves the sensitivity of detection vehicles.Meanwhile,it reduces the detection interference of environmen-tal temperature.The experimental results show that this system can exactly indicate if there are passing vehicles.At present,the system has been successfully applied to hilly road.The system can greatly decrease accident.
上傳時間: 2013-10-10
上傳用戶:歸海惜雪
在汽車發(fā)動機起動時,若發(fā)動機起動后起動機不能及時斷電,將會燒毀起動機或損壞飛輪齒環(huán);若變速器不在空檔位置起動,則起動機的瞬間動力將使汽車位移,還可能引起交通事故和人身安全。為此介紹一種利用NXP P89LPC901單片機控制的汽車起動保護控制器,通過檢測汽車起動開關(guān)、變速箱檔位、發(fā)動機轉(zhuǎn)速,實現(xiàn)對汽車發(fā)動機起動過程檢測和保護。起動保護控制器在發(fā)動機起動過程中通過采用逐個關(guān)閉打開負載系統(tǒng),解決汽車發(fā)動機過程中因起動電流大而對汽車電源的沖擊影響,延長了電瓶壽命。 Abstract: When the automotive engine is started, the engine start motor and flywheel gear may be damaged, even traffic accidents and personal safeties may be caused by wrong operation or other factors.In order to ensure the automotive engine can be started normally and safely,it is necessary that the protecting measures and methods are considered in the automotive electrical control system.This paper introduces a kind of the automotive engine starting protect controller based on NXP P89LPC901 MCU.The controller can protect the engine starting process by detecting the starter key switch,transmission stall and engine speed.Through the use of close and open load system,the controller can solve the impact on automotive power because of the high-current load in the process of the automobile engine starting, and extend battery life.
上傳時間: 2013-10-15
上傳用戶:mikesering
為滿足礦井安全生產(chǎn)要求,介紹了一種以AT89C51單片機為主控器,對環(huán)境空氣的溫度、有毒易燃氣體的濃度等進行檢測的監(jiān)控系統(tǒng)。該系統(tǒng)配合外圍電路能實現(xiàn)對上述環(huán)境指標的控制并存儲相關(guān)數(shù)據(jù)與上位PC機通信。它采用硬件抗干擾和軟件抗干擾技術(shù),以確保整個系統(tǒng)工作的準確性。 Abstract: In order to meet the needs of mine produce safety,a kind of intellignet mine ambient monotoring and control system based on AT89C51 is introduced.This system can detect the temperature of ambient of mine,the density of poisonous inflammable gas,combined external circuit.With its function part, this system can change above-mentioned elements.
上傳時間: 2013-11-10
上傳用戶:wendy15
為了解決磁放大器性能測試過程中,需要對其供給不同數(shù)值恒定電流的問題,設(shè)計了一種基于DAC7512和單片機的數(shù)控恒流源系統(tǒng)。該系統(tǒng)采用AT89C51作為主控器件,將計算機發(fā)送的電流控制字命令轉(zhuǎn)換為D/A轉(zhuǎn)換器控制字,通過模擬SPI通信接口,寫D/A控制字到DAC7512,從而控制其輸出相應數(shù)字電壓值,經(jīng)差動縮放電路、電壓/電路變換電路和功率驅(qū)動電路,最后輸出恒定電流。實驗結(jié)果表明,恒流源輸出電流調(diào)節(jié)范圍為-45~+45 mA、精度為±0.1 mA,分辨率達0.024 4 mA,具有應用靈活,外圍電路簡單,可靠性高的特點。該數(shù)控直流恒流源也可為相關(guān)產(chǎn)品的測試系統(tǒng)研發(fā)提供參考。 Abstract: In order to solve the need to supply different values constant current for the magnetic amplifier in testing process, numerical control constant current source system was designed based on DAC7512 chip and microcontroller technology. The system used the AT89C51 as the main chip, which can convert the current control word from computer into to D/A control words. And the system wrote D/A control word into the DAC7512 chip to control the output voltage value by the SPI communication interface, which can output corresponding constant current figures by scaling circuit, the V/I converter and power drive circuit. Experimental results show that the current source output current adjustment range is -45~+45mA, accuracy is ± 0.1mA, and resolution ratio is 0.024 4mA
上傳時間: 2014-12-27
上傳用戶:invtnewer
為深入了解基于UC3854A控制的PFC變換器中的動力學特性,研究系統(tǒng)參數(shù)變化對變換器中分岔現(xiàn)象的影響,在建立Boost PFC變換器雙閉環(huán)數(shù)學模型的基礎(chǔ)上,用Matlab軟件對變換器中慢時標分岔及混沌等不穩(wěn)定現(xiàn)象進行了仿真。在對PFC變換器中慢時標分岔現(xiàn)象仿真的基礎(chǔ)上,分析了系統(tǒng)參數(shù)變化對分岔點的影響,并進行了仿真驗證。仿真結(jié)果清晰地顯示了輸入整流電壓的幅值變化對系統(tǒng)分岔點的影響。 Abstract: In order to better understand the dynamics characteristic of power factor correction converter based on UC3854A, and make the way that parameters change influences the bifurcation phenomena of the system clearly. The math model of the two closed loop circuits to the Boost PFC (Power Factor Correction) converter controller was built. Then, with the help of Matlab, the simulation for nonlinear phenomena such as chaos and slow-scale bifurcation in the PFC converter was made. Finally the factors that have influence to the phenomenon of bifurcation under slow-scale in PFC converter were analyzed. The simulation results clearly show the parameters change influences the bifurcation point of the system.
上傳時間: 2013-10-17
上傳用戶:杜瑩12345
為降低成本和解決現(xiàn)有膜片鉗放大器系統(tǒng)中PC機的干擾問題,研究了一種基于單片機的膜片鉗放大器小系統(tǒng)。該系統(tǒng)采用ADI公司生產(chǎn)的ADuC841作為控制核心,并且配置相應的液晶顯示模塊LCM3202401。模擬電路部分采用高輸入阻抗的AD8627實現(xiàn)微電流信號的采集,并由后級電路進行信號的放大和電阻電容的補償。它具有硬件電路簡單、體積小、使用方便的特點。既可以單獨作為小系統(tǒng)實現(xiàn)采集和顯示,也可以通過紅外方式和PC機進行通訊,在PC機上進行信號的處理。 Abstract: In order to reduce cost and resolve the interferential problem with PC in existing patch clamp amplifiers, a small patch clamp amplifier system design based on microcontroller is studied. It adopts a new high performance microconverter ADuC841 by the ADI as the control core in the system, configuring a liquid crystal module LCM3202401. In the analog circuit, AD8627 with high input impedance is used to detect the low current,signal magnification, as well as resistance and capacitance compensation are accomplished by subsequent circuits. It has the advantage of simple hardware circuit design, small volume and convenient operation. It can either be used as an independent system to measure and show signal detected or transmit to PC by infrared ray.
上傳時間: 2013-11-06
上傳用戶:yy_cn
為了提高環(huán)境參數(shù)采集的自動化水平,提升效率,設(shè)計了無線傳感器系統(tǒng)。本系統(tǒng)運用了傳感器技術(shù)、通信技術(shù)和單片機技術(shù),實現(xiàn)了對環(huán)境溫度、濕度、光照度以及可燃性氣體濃度等參數(shù)的檢測。它能夠?qū)崟r地與上位機進行無線通信,滿足對環(huán)境參數(shù)實時監(jiān)測的要求。 Abstract: In order to increase the degree of automation and improve the efficiency of the environment monitoring parameters,the wireless sensor system was developed.Combining with the technique of sensor,automatic monitoring,communication and single-chip microcomputer,it realized real-time monitoring environment parameters,such as temperature,humidity,illumination,concentration of com- bustible gas and so on.At the same time it can communicate with upper personal computers,satisfy the desire of real-time monitoring.
上傳時間: 2013-11-22
上傳用戶:longlong12345678
為解決輸油管道溫度壓力參數(shù)實時監(jiān)測的問題,設(shè)計了以C8051F930單片機作為控制核心的超低功耗輸油管道溫度壓力遠程監(jiān)測系統(tǒng)。現(xiàn)場儀表使用高精度電橋采集數(shù)據(jù),通過433 MHz短距離無線通信網(wǎng)絡與遠程終端RTU進行通信,RTU通過GPRS網(wǎng)絡與PC上位機進行遠程數(shù)據(jù)傳輸,在上位機中實現(xiàn)數(shù)據(jù)存儲和圖形化界面顯示,從而實現(xiàn)輸油管道溫度壓力參數(shù)的實時監(jiān)測和異常報警。經(jīng)實驗證明,該系統(tǒng)的12位數(shù)據(jù)采集精度滿足設(shè)計要求,漏碼率小于1%,正常工作時間超過5個月,能實時有效地監(jiān)測輸油管道的溫度壓力參數(shù),節(jié)省大量人工成本,有效預防管道參數(shù)異常造成的經(jīng)濟損失和環(huán)境污染。 Abstract: In order to solve the problems on real-time monitoring of pipeline temperature and pressure parameters, the ultra-low power remote pipeline temperature and pressure monitoring system was designed by using the single chip processor C8051F930 as the control core. The high-precision electric bridge was used in field instruments for data collection, the 433MHz short-range wireless communication network was used to make communication between field instrument and RTU, the GPRS was used by the RTU to transmit data to the PC host computer, and the data was stored and displayed in the PC host computer, so the real-time monitoring and exception alerts of pipeline temperature and pressure parameters were achieved. The experiment proves that the system of which error rate is less than 1% over five months working with the 12-bit data acquisition accuracy can effectively monitor the pipeline temperature and pressure parameters in real time, it saves a lot of labor costs and effectively prevents environmental pollution and economic losses caused by abnormal channel parameters.
標簽: C8051F930 溫度 壓力 遠程監(jiān)測系統(tǒng)
上傳時間: 2013-11-07
上傳用戶:cuibaigao
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