说明：  AD接口实验：通过电位器调节输出电压，电位器输出电压经过A/D转换获取电压实际值显示在数码管上，并把定时采集数据实时上传到PC机
(AD Interface Experiment: The potentiometer adjusts the output voltage, potentiometer output voltage through the A/D converter for voltage is the actual value displayed in the digital pipe, and to regularly collect data real-time upload to PC,)