/*!
    \file    readme.txt
    \brief   description of the FAC polling fir filter demo

    \version 2026-02-10, V1.4.0, demo for GD32G5x3
*/

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*/

  This demo is based on the GD32G553Q-EVAL-V1.0 board, it provides a description of 
how to use the FAC polling fir filter.The sampling frequency is 16KHz,the FIR filter 
order is 20,cut-off frequency is 800Hz.The amplitude of useful signal is 25000 and the 
frequency is 500Hz, and the amplitude of noise signal is 5000 and the frequency is 2500Hz.
The filtering effect can be verified by comparing the difference between the reference_data 
and the calculated_data,the error can be displayed by the error array,which converges gradually.
