設計了一種基于PIC16C71單片機的數字水溫配制閥。該配制閥采用NTC熱敏電阻作溫度傳感器,與固定電阻組成簡單分壓電路作為水溫測量電路,利用PIC16C71單片機內置的8位A/D轉換器把熱敏電阻上的模擬電壓轉換為數字量,PIC16C71單片機控制直流電機驅動混水閥調節冷熱水的混合比例實現水溫調節。給出了控制電路圖,對水溫測量電路的參數選擇和測溫精度作了詳細討論。實驗和分析表明,選用阻值較大的NTC熱敏電阻和分壓電阻可較好地解決熱敏電阻因功耗較大造成的熱擊穿問題。 Abstract: A digital valve for controlling water temperature based on PIC16C71 was presented in this paper.A bleeder circuit which consisted of a NTC thermistor as temperature sensor and a fixed resistance was designed as water temperature measuring circuit.The analog voltage on the thermistor was converted into digital signal by a 8-bit A/D converter embedded in PIC16C71. Based on the digital signal, the MCU PIC16C71 drived the valve by a DC motor to adjust the water temperature through adjusting the proportion of hot water and cold water.The circuit diagram of controller was given,the principle,the component parameters and the accuracy of measuring temperatures were also dissertated in detail. It was found by experiment and analysis that thermal breakdown of thermistor caused by high power could be solved by selecting thermistor and fixed resistance with high impedance value.
上傳時間: 2013-11-08
上傳用戶:Yue Zhong
針對目前使用的RS232接口數字化B超鍵盤存在PC主機啟動時不能設置BIOS,提出一種PS2鍵盤的設計方法。基于W78E052D單片機,采用8通道串行A/D轉換器設計了8個TGC電位器信息采集電路,電位器位置信息以鍵盤掃描碼序列形式發送,正交編碼器信號通過XC9536XL轉換為單片機可接收的中斷信號,軟件接收到中斷信息后等效處理成按鍵。結果表明,在滿足開機可設置BIOS同時,又可實現超聲特有功能,不需要專門設計驅動程序,接口簡單,成本低。 Abstract: Aiming at the problem of the digital ultrasonic diagnostic imaging system keyboard with RS232 interface currently used couldn?蒺t set the BIOS when the PC boot, this paper proposed a design method of PS2 keyboards. Based on W78E052D microcontroller,designed eight TGC potentiometers information acquisition circuit with 8-channel serial A/D converter, potentiometer position information sent out with keyboard scan code sequentially.The control circuit based on XC9536 CPLD is used for converting the mechanical actions of the encoders into the signals that can be identified by the MCU, software received interrupt information and equivalently treatmented as key. The results show that the BIOS can be set to meet the boot, ultrasound specific functionality can be achieved at the same time, it does not require specially designed driver,the interface is simple and low cost.
上傳時間: 2013-10-10
上傳用戶:asdfasdfd
以C8051F020為核心處理器,設計無線傳感器網絡數據采集系統。系統采用SZ05-ADV型無線通訊模塊組建Zigbee無線網絡,結合嵌入式系統的軟硬件技術,完成終端節點的8路傳感器信號的數據采集。現場8路信號通過前端處理后,分別送入C8051F020的12位A/D轉換器進行轉換。經過精確處理、存儲后的現場數據,通過Zigbee無線網絡傳送到上位機,系統可達到汽車試驗中無線測試的目的。 Abstract: This paper designs a wireless sensor network system for data acquisition with C8051F020 as core processors.The system used SZ05-ADV wireless communication module,set up a Zigbee wireless network, combined with hardware and software technologies of embedded systems,completed the end-node 8-locale sensor signal data acquisition.Eight locale signals were sent separately into the 12-bit ADC of C8051F020 for conversion through front treatment.After accurate processing and storage,the locale data was transmitted to the host computer through Zigbee wireless.The system achieves the purpose of wireless testing in vehicle trial.
標簽: C8051F020 Zigbee 汽車測試 系統設計
上傳時間: 2013-11-23
上傳用戶:dsgkjgkjg
提出了一種以S3C2440A為核心處理器的銀行評價器的設計方案,并結合XILINX公司的XL95144XL型CPLD,輔助S3C2440A,實現該銀行評價器的各部分功能以及系統信號之間的相互協調。該評價器在系統設計上采用液晶屏顯示,代替了以往簡單的數碼管電路的顯示模式,在視覺上給人以全新的享受。同時,評價器增加了新的網絡供電方式,只要將評價器連接上網絡就可以正常工作,方便了客戶的使用。總之,此款銀行評價器采用了嵌入式系統的設計方案,大大豐富了系統功能,實現一個銀行評價器設計的新突破。 Abstract: S3C2440A of SamSung company is the core component of the embedded system. A design of bank assessor based on S3C2440A was provided in this paper. It used XL95144XL combined with S3C2440A to realize all the functions and coordination with system signals. This bank assessor used LCD to display instead of the former simple digital display and provided a new seusuous enjoment. Meanwhile,it provided a new method of network power supply,that the bank assessor could regularly work once it connected to the network,which is convenient for customers to use. In a word,this assessor takes embedded system,enriches the system’s functions and reclizes a new breakout.
標簽: S3C2440A
上傳時間: 2013-11-03
上傳用戶:taa123456
為提高電容測量精度,針對電容式傳感器的工作原理設計了基于PIC16LF874單片機電容測量模塊。簡單闡述了電容測量電路的應用背景和國內外研究現狀,介紹了美國Microchip公司PIC16LF874單片機的特性。電容式傳感器輸出的動態微弱電容信號通過PS021型電容數字轉換器把模擬量數據轉換成數字量數據,所測數據由PIC16LF874單片機應用程序進行處理、顯示和保存。實驗結果表明,固定電容標稱值為10~20 pF 的測量值相對誤差在1%以內,同時也可知被測電容容值越大,測量值和標稱值相對誤差越小。 Abstract: To improve the accuracy of capacitance measurement,aimed at the principle of work of mercury capacitance acceleration transducer,the design of micro capacitance measurement circuit is based on the key PIC16LF874 chip. Briefly discusses the application of the capacitance measuring circuit for the background and status of foreign researchers,focusing on the United States PIC16LF874 microcontroller features. Capacitive sensor outputed signal through the dynamics of weak PS021-chip capacitors (capacitancedigital converter) to convert analog data into digital data,the measured data from the PIC16LF874 microcontroller application process, display and preservation. Experimental results show that the fixed capacitor 10pF ~ 20pF nominal value of the measured value of relative error is within 1%,but also it canbe seen the value of the measured capacitance larger,measuring value and the nominal value of relative error smaller.
上傳時間: 2013-10-29
上傳用戶:wojiaohs
生活中許多目標的高度和水平距離需要進行測量。目前主要的測量方法,仍以傳統的皮尺丈量為主,測量效率不高,有時還很不方便,沒有技術成熟的數字式測高測距產品。以基本的數學方法為理論依據,利用遙控小車做為載體,采用角度傳感器測量角度、霍爾傳感器測量水平距離等,通過單片機LM3S615進行數據計算,實現了對待測目標物體的高度、水平距離等數據的快速、精確和數字式的測量,高度測量精度可達99.06%,水平測量精度則可達98.06%。 Abstract: In our lives, the height and horizontal distance of some goals are needed to be measured. Because the currently used methods are still traditional tape-based measuring methods, and the measuring efficiency is low and inconvenient so some kinds of digital and portable measuring methods or instruments are needed. Based on the basic math theory, this paper designed and manufactured a portable, digital and remote controlled measuring mobile small vehicle, which assembled with angle measuring sensor for angle measurement and Hall sensor for horizontal distance measuring. MCU LM3S615 calculated the height and horizontal distance data gotten from these sensors. The measuring process is simple, the measuring results are more accurate and the measuring efficiency is higher than traditional measure instruments. The accuracy of height and distance measurement can reach 99.06% and 98.06%.
上傳時間: 2013-10-30
上傳用戶:jackandlee
介紹一種基于C8051單片機的動態心電監護系統。該系統由兩部分組成:以C8051F320單片機為核心的數據采集裝置和以PC機為平臺的分析處理系統。硬件電路功耗低,由單片機自帶的USB接口將數據傳送給PC機。軟件平臺采用LabVIEW可視化虛擬儀器系統開發平臺,將傳統儀器的功能模塊集成到計算機中,用戶可通過修改虛擬儀器的程序改變其功能。采用USB接口實時傳輸心電數據,并將數據采集模塊設計為計算機外設,使該系統高速快捷、小巧便攜。 Abstract: In this design,a low-cost ECG electrocardiogram monitoring system is introduced,which consists of two parts:data acquisition device based on C8051F320and PC terminal as the analysis and processing system.The system is low-power consumption,the data is transmitted to the PC terminal by USB interface of the C8051F320.By using the visible virtual instrument system developing platform LabVIEW,the traditional instruments function modules are integrated into the computer,so the user can modify virtual instrument software to change its function to meet their needs.Using USB in-terface to realize real-time ECG data transmission,in addition,ECG data acquisition module is designed as the computer peripheral,which makes the syetem high-speed and portable.
上傳時間: 2013-11-13
上傳用戶:zhangzhenyu
介紹一種基于CAN總線的牽引變電站自動化系統通訊規約的設計,CAN通訊規約采用標準幀,報文采用主動發送和發送查詢兩種處理形式。該設計在城市輕軌與地鐵牽引變電站中的應用表明:可實現間隔層和通訊處理層的數據快速、可靠的交換,提高牽引變電站的安全性和穩定性 。 Abstract: This paper firstly presents a kind of design dealing with communicational protocol to the traction substation automation system based on CAN bus,and then comes up with the ideas that all frames of CAN communicational protocol should adopt the standard frame,and that messages be processed by two ways:sending initiatively and sending quiries.Subway and light rail application shows that the use of the CAN bus is possible to exchange data quickly and reliably between the layers of the middle and the communicational processing,hence to improve the safety and stability of traction substations.
上傳時間: 2013-11-07
上傳用戶:bs2005
介紹了一種TI公司最新推出的MSP430F247單片機,利用它自帶的I2C模塊驅動I2C總線的溫度傳感器TMP275。TMP275是一款具有高精度、低功耗的新型溫度傳感器。由于TMP275具有可編程功能,纖小的封裝以及極大的溫度范圍,因而廣泛應用于組建超小型溫度測量裝置。 Abstract: A new single chip microcomputer MSP430F247 which is released by TI is introduced.It can drive I2C interface digital temperature sensor TMP275 with I2C module.TMP275 is a new temperature sensor which has high accurate,low power. Because TMP275 has programmable function,small packages and wide temperature range,it is applied widely in very little temperature measurment equipment.
上傳時間: 2013-12-06
上傳用戶:asdfasdfd
介紹了一種基于C8051F020單片機的多路壓力測量儀。該測量儀選用電阻應變式壓力傳感器采集壓力信號,并經放大電路處理后送入C8051F020單片機,再由C8051F020單片機內部的A/D轉換器將采集到的壓力信號進行模數轉化,然后分別對數據進行存儲和顯示。該測量儀能測量6路壓力信號,并且各測量點都能單獨檢測和設置。由于采用了C8051F020單片機,簡化了硬件電路,增強了抗干擾能力,使得測量儀具有測量精度高,沖擊小等特點。 Abstract: A measurement apparatus for multi-channel pressure based on single chip microcomputer is introduced.It can measure 6 channels signal of the pressure,and the pressure measure points can be detection and located individually.The pressure signal sampling is obtained by resistor stress-type pressure sensors,the digital signals of 6 channels are collected through amplifying and adjustment circuit of pressure signals and internal integrated A/D converter of MCU.Finally,and it realizes the function to store and display data separately.C8051F020 was used to made hardware circuit simple,and it also enhanced the anti-interference ability.It features high precision and little impact.
上傳時間: 2013-11-16
上傳用戶:yare