/*!
    \file    readme.txt
    \brief   description of the FAC iir polling filter example

    \version 2025-07-15, V1.0.0, firmware for GD32G5x3
*/

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*/

  This example is based on the GD32G553Q-EVAL-V1.0 board, it provides a description of 
how to use the FAC iir polling  filter.The sampling frequency is 16KHz,the IIR filter 
order is 2,cut-off frequency is 500Hz.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.