本课程设计要求熟悉89s51的原理及使用方法，来设计一个能够测量一定频率范围的智能频率计。-Design requirements of this course are familiar with the principles and use of 89s51 approach to the design of a frequency range must be able to measuring the frequency of the smart.

功能极简单的基于HT1621芯片的遥控程序，成功控制89S51管脚输出-HT1621 features a very simple chip-based remote procedure successfully controlled 89S51 pin output