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  • 基于单片机的数字化B超键盘设计

    针对目前使用的RS232接口数字化B超键盘存在PC主机启动时不能设置BIOS,提出一种PS2键盘的设计方法。基于W78E052D单片机,采用8通道串行A/D转换器设计了8个TGC电位器信息采集电路,电位器位置信息以键盘扫描码序列形式发送,正交编码器信号通过XC9536XL转换为单片机可接收的中断信号,软件接收到中断信息后等效处理成按键。结果表明,在满足开机可设置BIOS同时,又可实现超声特有功能,不需要专门设计驱动程序,接口简单,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.    

    标签: 单片机 B超 数字化 键盘设计

    上传时间: 2013-10-10

    上传用户:asdfasdfd

  • 单片机控制的铅酸蓄电池充电电源

     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.    

    标签: 单片机控制 充电电源 铅酸蓄电池

    上传时间: 2013-11-16

    上传用户:cepsypeng

  • 单片机P0口的片外数据存储器扩展

    单片机作为一种微型计算机,其内部具有一定的存储单元(8031除外),但由于其内部存储单元及端口有限,很多情况下难以满足实际需求。为此介绍一种新的扩展方法,将数据线与地址线合并使用,通过软件控制的方法实现数据线与地址线功能的分时转换,数据线不仅用于传送数据信号,还可作为地址线、控制线,用于传送地址信号和控制信号,从而实现单片机与存储器件的有效连接。以单片机片外256KB数据存储空间的扩展为例,通过该扩展方法,仅用10个I/O端口便可实现,与传统的扩展方法相比,可节约8个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.

    标签: 单片机 P0口 数据存储器 扩展

    上传时间: 2014-12-26

    上传用户:adada

  • 基于MC9S12HZ256的总线式汽车数字仪表设计

    首先研究CAN总线和SAE J1939协议,提出一种基于MC9S12HZ256微控制器的总线式汽车数字仪表解决方案。详细介绍SAE J1939协议的报文帧格式及应用层协议中发动机相关参数的定义,以及步进电机及其驱动和车速信号的处理方法。该数字仪表系统硬件平台由微处理器和信号采集和信息处理及显示等模块组成。软件设计部分编程实现了对CAN总线和各传感器数据的读取、处理。该系统能够实时反映车辆工况。 Abstract:  In this paper,CAN bus and SAE J1939protocol are researched,and a vehicle digital instrument solution based on MC9S12HZ256MCU is proposed.The message frame format and some engine-related parameters’definition in SAE J1939application layer protocol are introduced in detail.Stepper motor and its driver,the methods of speed signal process-ing are also introduced.The hardware platform of vehicle digital instrument is composed by MCU,signal acquisition mod-ule,and signal processing and displaying module.Data receiving and processing from CAN bus and sensors are accom-plished by programming,and vehicle condition can be reflected in real-time.

    标签: 256 MC9 S12 MC

    上传时间: 2013-10-20

    上传用户:huannan88

  • 基于AVR的新型防汽车追尾安全装置设计

    针对目前汽车追尾事件频发问题,提出一种防汽车车前和车后追尾的安全装置设计。该设计以高性能、低功耗的8位AVR微处理器ATmega8L为核心,结合霍尔式车速传感器、激光雷达测距装置和MMA7260QT加速度传感器,能够兼顾车前和车后,摒弃以往设计中只考虑车前或车后单一性缺点,尤其适用于高速、夜晚或新手行车。 Abstract:  Aiming at the high frequency of vehicle rear-end collision,a safe device design of anti-vehicle rear-end collision is presented.In the design,the high-performance,low-power8-bit AVR microprocessor ATmega8L is utilized as a core combined with Hall-type speed sensor,laser-radar ranging devices and the acceleration sensor MMA7260QT.The design considers both the front and back of a car,and overcomes the drawbacks of former designs in which only the front or the back of the car is considered,so it is especially suitable for high-speed,night or the beginner’s driving.

    标签: AVR 汽车追尾 装置

    上传时间: 2013-10-14

    上传用户:GavinNeko

  • 串行时钟PCF8583在微机保护装置中的应用

    实时时钟是微机保护装置的重要部件,在讨论PCF8583结构与功能的基础上,提出采用dsPIC33F系列微处理器与串行I2C时钟PCF8583的接口设计方案,给出了相应的接口电路与软件流程。该设计方案结构简单,可靠性高,开发周期短,具有一定的实用与参考价值。所设计的微机保护装置已投入现场运行,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.

    标签: 8583 PCF 串行时钟 中的应用

    上传时间: 2013-11-18

    上传用户:Thuan

  • 基于C8051F320的心电监护系统设计

    介绍一种基于C8051单片机的动态心电监护系统。该系统由两部分组成:以C8051F320单片机为核心的数据采集装置和以PC机为平台的分析处理系统。硬件电路功耗低,由单片机自带的USB接口将数据传送给PC机。软件平台采用LabVIEW可视化虚拟仪器系统开发平台,将传统仪器的功能模块集成到计算机中,用户可通过修改虚拟仪器的程序改变其功能。采用USB接口实时传输心电数据,并将数据采集模块设计为计算机外设,使该系统高速快捷、小巧便携。 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.

    标签: C8051F320 心电监护 系统设计

    上传时间: 2013-11-13

    上传用户:zhangzhenyu

  • 基于C8051F310的山路转弯预防警示系统

    针对盘山路存在的转弯盲区,即在转弯时司机无法得知弯路对面是否有车辆通过,设计一种基于C8051F310的山路转弯预防警示系统。该系统利用一阶滤波算法检测山路转弯时是否有车辆通过。运用该算法可增强系统检测的实时性,提高检测机动车辆的灵敏度,同时大大减少环境温度对检测的干扰。试验表明该系统能够正确指示出在山路转弯时是否有车辆通过,目前该系统已安装在盘山路上,可大大减少事故的发生率。 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.

    标签: C8051F310 转弯

    上传时间: 2013-10-10

    上传用户:归海惜雪

  • 基于AT89S52的机载电气盒测试仪的设计

    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.

    标签: 89S S52 AT 89

    上传时间: 2014-12-27

    上传用户:786334970

  • 基于CDC3207G的汽车仪表板设计

    应用德国Micronas公司的CDC3207G微控制器开发了一款汽车仪表板系统。详细地介绍了该系统的硬件原理,以及步进电机,音频控制,LCD显示,LED指示灯和报警灯等几个模块的实现方法。应用μC/OS-II实时操作系统开发软件。着重介绍了启动代码的设计和任务的规划。 Abstract:  A dashboard system is developed by using CDC3207G microcontroller made by Micronas.The hardware of the sys-tem and the realization of the step motor module,audio module,LCD display and LED indicator and alarm module are ex-plained in detail.The μC/OS-II real-time operating system is used for the software development and the starting code design and the task planning is explained specifically.

    标签: 3207G 3207 CDC 汽车仪表板

    上传时间: 2013-10-26

    上传用户:x4587