说明：  把R、L、C转换成频率信号f，转换的原理分别是RC振荡电路和LC电容三点式振荡电路。单片机计数得出被测频率，由该频率计算出各个参数值，数据处理后，送显示。
(The R, L, C converted into frequency signal f, the principles of conversion are RC oscillator circuit and three-point capacitance LC oscillator circuit. Singlechip count reached the measured frequency, calculated by the frequency of the various parameters, data processing, the delivery shows.)