无线抢答记分系统以AT89S52/51单片机为控制核心,主持人电路可实现有效抢答信号的无线译码接收与识别显示、抢答倒计时、答题倒计时、提示报警等功能,选手电路可实现抢答信号的编码与无线发送、分数数据的无线译码接收显示,主持人和选手之间通信采用UM3758-108A编译码器和红外发送接收模块配合实现。
上传时间: 2013-11-02
上传用户:zmy123
基于STC89C52单片机的全自动充电机设计
上传时间: 2014-12-26
上传用户:李彦东
基于GSM无线传输的远程抄表终端设计论文
上传时间: 2013-10-21
上传用户:JIEWENYU
单片机无线串行接口电路设计
上传时间: 2014-01-16
上传用户:aix008
无线遥控模块(单片机)
上传时间: 2013-10-13
上传用户:netwolf
为了有效地提升铅酸蓄电池的使用寿命,同时实现对充电过程的监控,设计出一种用单片机控制的36 V铅酸蓄电池充电电源。本电路采用反激式拓扑,连续电流工作模式,电源管理IC设计在电源的副边,由ELAN公司的EM78P258N单片机模拟,是用可编程器件模拟电源管理IC,实现智能电源低成本化的一次成功尝试,通过对单片机的软件设计实现了充电电源的状态显示、充电时间控制、报警、过温保护、过压保护、过流保护等功能。本充电器真正的实现了铅酸蓄电池的三段式充电过程,其最高输出功率可达90 W,效率约85%,成本不到20元,具有很高的市场竞争力。 Abstract: In order to extend the life of lead-acid battery efficiently and supervise the charging process meanwhile, a 36V lead-acid battery charge powe supply controlled by microcontroller is designed. The charger is flyback switching power supply and works in CCM mode. A EM78P258N microcontroller made by ELAN microelectronics corporation is used as power management IC which is designed at the secondary circuit. The project is a successful attempt to low-cost intelligent power used microcontroller simulating power management IC. The charger also has the functions of the status reveal, charge time control, alarming, thermal protect, current limit and overvoltage protect by the software design. The circuit actually implements the three-step charge process, whose power is up to 90W and whose efficiency can get 85%. The net cost of this charger is less than 20 RMB, so that the charger is of powerful market competitiveness.
上传时间: 2013-11-16
上传用户:cepsypeng
为提高温度测量效率,降低系统的成本,扩展传输距离,设计出一种新型温度采集系统。单片机通过控制具有单总线方式的温度传感器DS18B20实现对温度的测量,同时单片机通过控制具有单总线方式300~450MHz频率范围内的MAX7044与MAX7033无线发射与接收芯片实现温度数据的无线传输。与传统温度采集系统相比,该系统利用单总线方式连接,采用无线传输方式实现远距离通信,易于系统的集成与扩展。实验结果表明,该系统结构简单、方便移植,能够同时实现多达上百点温度的测量与500m范围的传输。 Abstract: To improve the temperature measurement efficiency and reduce system cost,expansion of transmission distance,a new type of temperature acquisition system is designed.Microcontroller controlled temperature sensor DS18B20which has a single-bus achieves temperature measurement,while microcontroller by controlled the MAX7044and MAX7033chip with a single-bus and having300~450MHz radiofrequency to achieve the wireless transmission of temperature data.Compared with conventional temperature acquisition system,the system uses single-bus connected,and uses wireless transmission means to achieve long-distance communications,easy-to-system integration and expansion.The experimental results show that the system is simple,convenient transplantation,and can be implemented in as many as a hundred-point temperature measure-ment and the transmission range of500meters.
上传时间: 2013-10-29
上传用户:515414293
飞机电网故障时,机载电气盒必须在延迟时间内切断电网,保护机载设备。采用AT89S52设计的电气盒测试仪能够测试电气盒保护功能,测量延迟时间。实际应用结果表明,该测试仪具有测量准确、可靠性高、成本低等优点。 Abstract: The helicopter-electrical-box must shut off the helicopter power,protect the equipments of the helicopter when the helicopter power is failed.The tester for the helicopter-electrical-box based on AT89S52is used for testing the protect-ing function and measuring the delay time.Application results show this tester has some advantages,such as accurate mea-surement,high dependability,economical cost etc.
上传时间: 2014-12-27
上传用户:786334970
介绍一种简单射频识别系统设计。该设计包括阅读器、应答器和线圈3部分。由单片机控制阅读器向应答器发射无线信号,并接收应答器回送的信号,再通过分析回送信号识别物品。阅读器和应答器之间以半双工通信方式通信。 Abstract: A simple design of radio frequency identification system is given in this paper.The design includes reader,responder and winding.Through MCU,signals are sent to responder from reader,then corresponding signals are sent back. According to the analysis of the signals sent back,the objects can be identified.Half-duplex communication is adopted? between? reader? and? responder.
上传时间: 2013-10-11
上传用户:plsee
基于幅移键控技术ASK(Amplitude-Shift Keying),以C8051F340单片机作为监测终端控制器,C8051F330D单片机作为探测节点控制器,采用半双工的通信方式,通过监控终端和探测节点的无线收发电路,实现数据的双向无线传输。收发电路采用直径为0.8 mm的漆包线自行绕制成圆形空心线圈天线,天线直径为(3.4±0.3)cm。试验表明,探测节点与监测终端的通信距离为24 cm,通过桥接方式,节点收发功率为102 mW时,节点间的通信距离可达20 cm。与传统无线收发模块相比,该无线收发电路在受体积、功耗、成本限制的场合有广阔的应用前景。 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.
上传时间: 2013-10-19
上传用户:xz85592677