说明：  1 学习在CVI环境里面使用非NI数据采集卡。 2 学习用过零法计算被测每个周期采样点数。 3 学习数据采集卡采样间隔的测定。 4 学习计算被测信号的频率和周期。 5 熟悉FFT算法原理。
(One study in the CVI environment inside the use of non-NI data acquisition card. 2 study used method to calculate the measured zero sampling points per cycle. 3 study data acquisition card sampling interval measurement. 4 study calculated the measured signal frequency and cycle. 5 familiar with the FFT algorithm.)