业设计（论文）自行车里程表的设计.doc

毕业设计（论文） 题 目： 自行车里程表的设计 摘 要 本文介绍的速度与里程表设计以单片机最小系统和霍尔传感器为核心。传感器将不同车速转变成的不同频率的脉冲信号输入到单片机进行控制与计算，再采用LED模块进行显示，使得电动自行车的速度与里程数据能直观的显示给使用者。 本系统由霍尔传感器、RC滤波电路、单片机AT89S51、系统化LED显示模块、数据存储电路和键盘控制组成。其中霍尔传感器包含信号放大和波形整形。对待测信号进行放大的目的是降低对待测信号的幅度要求；波形变换和波形整形电路则用来将放大的信号转换成可与单片机相连的TTL信号；通过单片机的设置可使内部定时器T1对脉冲输入引脚T0进行控制，这样能精确地算出加到T0引脚的单位时间内检测到的脉冲数；设计中速度显示采用LED模块，通过速度换算得来的里程数采用I2C总线并通过E2PROM来存储，既节省了所需单片机的口线和外围器件，同时也简化了显示部分的软件编程 本文先对里程表设计当中所需设备作了详细介绍，对设计中存在的问题进行了说明；而后对硬件和软件部分的设计和实现作了认真的分析；然后给出了系统的建模过程及相应的系统模型，在此基础上进行了控制仿真，并对仿真效果进行了比较。 本里程表的设计具有结构简单，成本低廉，显示清晰，稳定可靠等优点。并且可进行扩充，加入时速表的功能，更加方便的了解你现在所处的情况。 关键词：单片机最小系统，LED数码管，霍尔传感器，RC滤波器,EEPROM存储器。 Abstract This paper describes the design speed and Odometer to SCM system and the smallest Hall sensor at the core. Different speed sensor into different frequency pulse signal input to the microprocessor control and calculation adopt LED modules, making the speed of electric bicycles and mileage data can be directly displayed to the user. The system consists of Hall sensor, RC filter circuit, SCM AT89S51, systematic LED display modules, data storage and keyboard control circuit components. Hall sensor which contains signal amplification and waveform shaping. Deal signals measured amplification of the treatment is to reduce the rate of measured signals; Waveform transform and waveform shaping circuit will be used for amplification of the signal can be converted into SCM connected with TTL signals; SCM through the setup will enable the internal timer T1 pulse input pin T0 control, This can be accurately calculated foisted T0 pin unit time detection of the pulse; Design LED display modules, through a conversion rate of mileage using I2C bus through E2PROM to storage, saved for SCM mouth lines and external devices, but also simplify the show part of the software program This article first right Odometer designs required equipment, details of the design issues of; Later on hardware and software design and implementation carefully analyzed; The