为了克服传统频率测量法不能满足等精度要求的缺点，提出一种基于AT89C51的等精度频率测量系统的设计方案。
本文论证了系统方案的选取，阐述了系统的总体功能、设计框架。重点分析了系统各功能模块的硬件和系统软件的解决方案，硬件平台由最小单片机系统、整形电路、分频电路、LCD显示电路四部分组成；软件部分包括主程序、LCD显示子程序、数据处理子程序。最后对系统性能进行测试，实验结果表明，该系统性能稳定，可靠性高。
In order to overcome the traditional frequency measurement method can not meet the precision requirements of shortcomings, proposed one kind based on the AT89C51 of equal precision frequency measurement system design.
This paper discussed the system plan selection, expounds the system function, design framework.Focus on the analysis of the various functional modules of the system hardware and system software solutions, hardware platform by the smallest single-chip system, shaping circuit, a frequency dividing circuit, LCD display circuit is composed of four parts; part of the software includes a main program, LCD display subroutine subprogram, data processing.Finally, we test the performance of this system, the experimental results show that, the system has a stable performance, high reliability.