用digilent公司的basys3开发板，外接Pmodmic和PmodAMP2模块，实现对声音的采集和复原。程序基于VIVADO 2015.4，附带例化的低通滤波器。实际可用。(Use digisen's basys3 development board, external Pmodmic and PmodAMP2 modules to achieve sound collection and recovery. The progra