用fir滤波器处理处理外部输入的音频信号，通过卷积处理，模数变换后，将输入的音频信号和fir滤波器的卷积值输出给DSP-Fir filter processing with external input audio signal processing, through the convolution processing, analog-digital conversion, the input audio signal and the convolution of fir filter out

基于stc12c5a60s2的 fft音频快速傅里叶变换，可以扩展做数字滤波器-Fft audio based stc12c5a60s2 the fast Fourier transform, digital filters can be extended to do