便携式多功能频率计的设计与实现

Design and Realization of Portable Multifunctional Frequency Meter

为了解决当前频率计功能单一化、频率测量精度过低、测量反应速度过慢、操作过于繁琐等问题,基于Cortex-M0内核,结合外部中断计数法与定时器计数法,设计了高精度便携式多功能频率计。该频率计的系统电路主要由显示电路、信号处理电路、方波放大电路、LED数码管显示电路、时钟电路等组成,其软件部分采用模块化和层次化设计方法,关于控制方波的产生与模拟信号的分析与处理,运用了高性能低功耗的STM32F103C6T6单片机,操作界面设计更加简便。实验结果表明:频率计可测量幅值在33~5.5 V,频率在1 Hz~1 MHz的方波、正弦波等信号,测量误差达到0.1 Hz;系统可产生幅值在3.3~8.5 V,频率在1 Hz~1 MHz的方波,且方波占空比可以通过按键进行调节。

In order to solve the problems of single function,low frequency measurement accuracy,slow measurement response speed and cumbersome operation of the current frequency meter,a high-precision portable multifunctional frequency meter was designed based on Cortex-M0 core,combined with external interrupt counting method and timer counting method.The system circuit of the frequency meter was mainly composed of display circuit,signal processing circuit,square wave amplification circuit,LED nixie tube display circuit,clock circuit,etc.The software part adopted modular and hierarchical design method.For the generation of control square wave and the analysis and processing of analog signal,STM32F103C6T6 single chip microcomputer with high performance and low power consumption was used,and the operation interface was designed more simply.The frequency meter can measure square wave,sine wave and other signals with amplitude of 3.3~5.5 V and frequency of 1 Hz~1 MHz,and the measurement error is up to 0.1 Hz.The system can generate square waves with amplitude of 3.3~8.5 V and frequency of 1 Hz~1 MHz,and the duty cycle of square wave can be adjusted by pressing the key.