说明：  该系统是基于声卡的多功能信号发生器的系统设计，主要是利用计算机的声卡实现波形的发生与输出，结合labview中的一些波形发生函数，在声卡上实现各种基本信号的发生和自定义信号的发生，并能把实时数据记录下来，实现历史数据的存储于回放。
(This system is based on the sound card of the multifunctional signal generator system design, mainly is to use computer sound card to realize the occurrence of waveform and output, combining with some of the labview function waveform occurs, on the sound card to realize all kinds of basic signals and custom, and can record the real-time data, historical data stored in the playback.)