用51单片机实现简单的音乐播放生日快乐歌。

超声波测距 利用 送接受的时间 差计算得到距离-Ultrasonic Ranging acceptable use to send the time difference calculated by the distance

24c64子程序，主程序直接调用就可以使用

独立式按键扫描并在一个LED数码管上显示相应的编号。-Stand-alone scan button and a LED digital tube display on the corresponding number.

89C51 LCD常用的初始化文件,开发环境为iccavr-89C51 LCD common initialization file, the development environment for iccavr

经过测试成功的PDIUSBD12与Mega8的连接代码，如有需要，可以下载，从PDISUBD12与S51单片机连接代码修改而来-PDIUSBD12 tested success Mega8 connection with the code, if necessary, can be downloaded from PDISUBD12 connection with the S51 code changes from single-chip microcomputer

又一个LCD1602的例程（主要是最近正在做相关的工作），已经调试通过。-Another LCD1602 routine (mainly related to the work being done recently), have been debugging through.

传感器应用实例电路设计150例，资源共享，敬请使用！-Sensor circuit design application 150 cases, resource sharing, please use!

lcd测试程序，C51的-LCD testing procedures C51

MAX485应用很广泛,可应用远程传输,信号衰减少.-MAX485 applications is very wide, and can be applied to long-distance transmission, the signal failure reduced.

步进电机程序，用l297 l298作为驱动电路的，程序比较简单，但是能对mcs-51中断有个详细认识-Stepper motor program l297 l298 as a driving circuit, the procedure is relatively simple, but can be interrupted for mcs-51 has a detailed understanding of