利用AT89C51型單片機定時和中斷功能，配以LM386型音頻功率放大器，構成了作息號音自動播放器，為學校和機關管理提供方便。 Abstract: Using timing and interrupt function of the AT89C51 single-chip microcomputer and the LM386 audio power amplifier.It is constituted the automatic bugle player.This player facilitates the institution and the school daily management.
上傳時間： 2013-10-10
上傳用戶：wivai
基于幅移鍵控技術ASK（Amplitude-Shift Keying），以C8051F340單片機作為監測終端控制器，C8051F330D單片機作為探測節點控制器，采用半雙工的通信方式，通過監控終端和探測節點的無線收發電路，實現數據的雙向無線傳輸。收發電路采用直徑為0.8 mm的漆包線自行繞制成圓形空心線圈天線，天線直徑為（3.4±0.3）cm。試驗表明，探測節點與監測終端的通信距離為24 cm，通過橋接方式，節點收發功率為102 mW時，節點間的通信距離可達20 cm。與傳統無線收發模塊相比，該無線收發電路在受體積、功耗、成本限制的場合有廣闊的應用前景。 Abstract: Based on ASK technology and with the C8051F340 and C8051F330D MCU as the controller， using half-duplex communication mode， this paper achieves bi-directional data transfer. Transceiver circuit constituted by enameled wire which diameter is 0.8mm and wound into a diameter （3.4±0.3） cm circular hollow coil antenna. Tests show that the communication distance between detection and monitoring of the terminal is 24cm，the distance is up to 20cm between two nodes when using the manner of bridging and the node transceiver power is 102mW. Compared with the conventional wireless transceiver modules， the circuit has wide application prospect in small size， low cost and low power consumption and other characteristics.
上傳時間： 2013-10-19
上傳用戶：xz85592677
在需要實時大量輸入漢字的顯示控制處理應用中，利用傳統單片機實現顯示控制的設計方法是較難實現的。帶漢字字庫的液晶模塊的使用使得小容量ROM單片機的大量漢字信息輸入與顯示成為可能。提出了針對漢字字庫編碼的二級索引拼音輸入檢索方法,介紹了以ST7920作為控制器的帶漢字字庫的液晶顯示模塊的接口方法及漢字顯示和控制原理，給出了通用計算機鍵盤在單片機中的串行接口，采用該技術可大大增強單片機的漢字輸入功能。為小容量ROM單片機的大批量漢字信息處理提供了一種漢字輸入解決方案。 Abstract: It is difficult to realize Chinese characters input method based on the embedded system by using the traditional design method of display control. It is possible to input and display Chinese characters based on the embedded system with the ROM of small content by using the LCD module with Chinese characters.Chinese characters input method of the quadric index recall in allusion to Chinese characters code is brought forward.The interface and the principle of Chinese characters display control based on the LCD module controlled with the ST7920 is introduced too.The serial interface of the computer keyboard in common use and the embedded system is given at the same time. It can enhance the embedded system function of Chinese characters input by using this technology, and provide a kind of Chinese characters input scheme for the embedded system with small capacity ROM.
上傳時間： 2013-11-19
上傳用戶：jhksyghr
為解決輸油管道溫度壓力參數實時監測的問題，設計了以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測系統。現場儀表使用高精度電橋采集數據，通過433 MHz短距離無線通信網絡與遠程終端RTU進行通信，RTU通過GPRS網絡與PC上位機進行遠程數據傳輸，在上位機中實現數據存儲和圖形化界面顯示，從而實現輸油管道溫度壓力參數的實時監測和異常報警。經實驗證明，該系統的12位數據采集精度滿足設計要求，漏碼率小于1%，正常工作時間超過5個月，能實時有效地監測輸油管道的溫度壓力參數，節省大量人工成本，有效預防管道參數異常造成的經濟損失和環境污染。 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.
上傳時間： 2013-11-07
上傳用戶：cuibaigao
將現行的供暖計費方式由按建筑面積計費變為按消耗的熱能計費是供暖計費方式發展趨勢，為了滿足這一計費方式變化的需要，設計了基于IC卡的預付費式新型供暖計費系統，通過測量用戶采暖系統進出口的溫度和流量，計算用戶消耗的熱能，利用IC卡記錄用戶預付費的金額和當年熱能的單價，根據熱能消耗和當年熱能的單價計算用戶采暖費，根據實際發生的供暖費用和預付費金額控制供暖的開停，這一計費方式的變化使供暖計費更趨合理。 Abstract: It is trend that the mode of heat charging is changed from billing by building area to by thermal energy. In order to meet the needs of heat charging mode changing， a new system of heat charging based on IC card is proposed. The user?蒺s energy consumption is calculated by measuring the user inlet and outlet temperature and flow，using the IC card to record the prepaid amount and the current price of heat. The user?蒺s heating costs is calculated according to energy consumption and current price， according to actual heating costs and prepaid amount，the system controls the heating opening or stopping. It is more reasonable that calculated heating costs by user heat consumption
上傳時間： 2013-10-14
上傳用戶：大融融rr
提出一種基于單片機AT89C51SND1C的MP3播放系統的設計方案。單片機集成了專用的解碼器，使用K9F1208閃存作為外存儲器，放音電路采用CS4330，存儲文件通過播放器上的USB接口設備從PC機上直接下載，液晶顯示采用LCD1602。方案設計簡單，性價比高，低功耗，易擴展。由于采用的是通用單片機實現的，可以很容易地移植到其他微控制器系統中，有很強的市場競爭能力和實用價值。 Abstract: A MP3 player design based on microchip AT89C51SND1C was presented, which used K9F1208 Flash chip as the memory circuit and used CS4330 as play chip. Storage files were download from PC through USB interfaces player on the device，and the LCD/602 was used as display screen. This system had characteristics of simple design,low power,easy expand，low cost and high recognition. Using of universual microchip make it easy to transplant to other microcontrol system，and have strong market competitiom and practical value.
上傳時間： 2014-12-27
上傳用戶：佳期如夢
針對當前安檢力學試驗機所能完成的試驗種類單一、自動化程度低等問題，提出一種以ATmega128單片機為核心控制器的安檢力學試驗機的設計。詳細闡述了該安檢力學試驗機各個組成部分的設計原理和方案，并且給出了各部分的軟件設計思想和操作流程。經過大量測試試驗表明：設計的安檢力學試驗機可以完成多達十余種的力學安檢試驗，完全符合相關國家標準，并且具有數據采集精度高、傳輸速度快、操作安全簡便等特點，實現了安檢設備的多功能化、數字化和自動化。 Abstract: Currently， many mechanical security testing machines have only one function. The degree of automation of them is low. To solve those problems， a new kind of mechanical security testing machine， using ATmega128 micro-controller as its core controller， has been advanced. It describes the components of the machine. The principles and the scheme in the designing processes are presented in detail， and the software architecture and the operation processes of each part are given. After having done many testing， we have reached the following conclusions: the mechanical security testing machine presented can do over ten mechanical security tests complying with related national standards. It has high data acquisition accuracy and high transmission speed. The operation of the machine is simple and safe. In general， this machine is a multi-functional， highly automatic， digitalized security testing device.
上傳時間： 2013-11-05
上傳用戶：a67818601
The SN65LBC170 and SN75LBC170 aremonolithic integrated circuits designed forbidirectional data communication on multipointbus-transmission lines. Potential applicationsinclude serial or parallel data transmission, cabledperipheral buses with twin axial, ribbon, ortwisted-pair cabling. These devices are suitablefor FAST-20 SCSI and can transmit or receivedata pulses as short as 25 ns, with skew lessthan 3 ns.These devices combine three 3-state differentialline drivers and three differential input linereceivers, all of which operate from a single 5-Vpower supply.The driver differential outputs and the receiverdifferential inputs are connected internally to formthree differential input/output (I/O) bus ports thatare designed to offer minimum loading to the buswhenever the driver is disabled or VCC = 0. Theseports feature a wide common-mode voltage rangemaking the device suitable for party-lineapplications over long cable runs.
上傳時間： 2013-10-13
上傳用戶：ytulpx
This application report discusses the design of non-invasive optical plethysmographyalso called as pulsoximeter using the MSP430FG437 Microcontroller (MCU). Thepulsoximeter consists of a peripheral probe combined with the MCU displaying theoxygen saturation and pulse rate on a LCD glass. The same sensor is used for bothheart-rate detection and pulsoximetering in this application. The probe is placed on aperipheral point of the body such as a finger tip, ear lobe or the nose. The probeincludes two light emitting diodes (LEDs), one in the visible red spectrum (660nm) andthe other in the infrared spectrum (940nm). The percentage of oxygen in the body isworked by measuring the intensity from each frequency of light after it transmitsthrough the body and then calculating the ratio between these two intensities.
標簽： Pulsoximeter Single-Chip Des
上傳時間： 2013-10-27
上傳用戶：黑漆漆
The PCA9516 is a BiCMOS integrated circuit intended forapplication in I2C and SMBus systems.While retaining all the operating modes and features of the I2Csystem, it permits extension of the I2C-bus by buffering both the data(SDA) and the clock (SCL) lines, thus enabling five buses of 400 pF.The I2C-bus capacitance limit of 400 pF restricts the number ofdevices and bus length. Using the PCA9516 enables the systemdesigner to divide the bus into five segments off of a hub where anysegment to segment transition sees only one repeater delay.
上傳時間： 2013-11-21
上傳用戶：q123321
