采用AT可编程器件,用ADC0809采集电压信号。
上传时间: 2013-11-03
上传用户:sunchao524
在理论分析循环码编码和译码基本原理的基础上,提出了基于单片机系统的(24,16)循环码软件实现编码、译码的方案。仿真结果表明(24,16)循环码能有效地克服来自通讯信道的干扰,保证数据通信的可靠及系统的稳定,使误码率大幅度降低。本论文对(24,16)循环码的研究结果表明,可以有效地降低错误概率和提高系统的吞吐量,实现纠错仅需要在接收端增加有限的存储空间和计算复杂度,具有一定的实用价值。 Abstract: Based on analyzing the theory of encoding and decoding of cyclic code, this paper showed the schemes of encoding and decoding of(24,16)cyclic code by the software and based on microcontroller. SimulATion results show thAT using (24,16) cyclic codes can effectively overcome the interference from communicATion channel, ensure the reliability and stability of dATa communicATion systems, and reduce the bit error rATe greATly. The results of this paper show thAT by using the (24,16) cyclic code, the error rATe can be reduced and the system throughput can be improved. Meanwhile, the system only needs to enlarge limited storage space and computATion the complexity AT the receiving end to realize error correction. Thus the (24,16) cyclic code has a practical value.
上传时间: 2013-11-09
上传用户:gaoliangncepu
Designing Boards with ATmel AT89C51,AT89C52, AT89C1051, and AT89C2051 for Writing Flash AT In-Circuit Test. Recent improvements in chips and testers have made it possible for the tester to begin taking over the role tradi-tionally assigned to the PROM program-mer. Instead of having a PROM pro- grammer write nonvolATile memories before assembling the board, the in-cir- cuit tester writes them during in-circuit testing operATions. Many Teradyne Z18- series testers are now in use loading code into nonvolATile memories, micro- controllers and in-circuit programmable logic devices. The purpose of this note is to explain how the Z18 approaches the writing task for ATmel AT89C series IC’s, so thAT designers of boards using these chips can get the best results.
上传时间: 2013-11-17
上传用户:xiaozhiqban
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.
上传时间: 2013-10-10
上传用户:asdfasdfd
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
为提高电容测量精度,针对电容式传感器的工作原理设计了基于PIC16LF874单片机电容测量模块。简单阐述了电容测量电路的应用背景和国内外研究现状,介绍了美国Microchip公司PIC16LF874单片机的特性。电容式传感器输出的动态微弱电容信号通过PS021型电容数字转换器把模拟量数据转换成数字量数据,所测数据由PIC16LF874单片机应用程序进行处理、显示和保存。实验结果表明,固定电容标称值为10~20 pF 的测量值相对误差在1%以内,同时也可知被测电容容值越大,测量值和标称值相对误差越小。 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.
上传时间: 2013-10-29
上传用户:wojiaohs
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.
上传时间: 2013-10-14
上传用户:GavinNeko
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.
上传时间: 2013-10-10
上传用户:归海惜雪
介绍一种采用单片机技术和基站器件EM4095的手持式低频RFID读卡器方案。首先对整个系统框架进行说明,然后介绍主要功能模块的设计,给出了各模块的原理图。重点描述了基站器件EM4095的性能参数和功能原理,最后描述了该系统的主程序流程图。 Abstract: In this paper,a handheld RFID reader based on MCU and EM4095 is introduced.AT first,the configurATion of this system is explained.Then the design of main modules and schemATic documents are particularly presented.The parameters and principle of the chip EM4095 are introduced in detail. AT last,the main software flow is given
上传时间: 2013-10-18
上传用户:windypsm
针对目前燃气灶市场的状况,提出一种基于PIC16C711单片机的燃气灶脉冲点火控制器设计,具体包括有系统的组成和功能介绍、硬件电路设计及软件功能实现。 Abstract: Aiming AT today’s gas cooker market, a pulse ignition controler design based on PIC16C711 is presented.The specific descriptions of system components and functions,hardware circuit design and software function are given.
上传时间: 2013-10-31
上传用户:zhqzal1014