程序内部含基准频率，可测量输入频率时变的信号 并画出频率变化波形(The program contains the reference frequency, which can measure the time-varying signal of input frequency and draw the waveform of frequency variation)

高频刷单，增加了时间控制，快速有效，只做交流之用，不对 盘后结果负责，供研究(high frequence, time control)