一阶RC低通滤波器

low_filter.h

复制

typedef struct

{

     int16_t  Input;

     int16_t  Output[2];

     int32_t  FilterTf;

     int32_t  FilterTs;

     int32_t  Kr;

     int32_t  Ky;

} low_filter;

void low_filter_init(low_filter *v);

int16_t low_filter_calc(low_filter *v);

low_filter.c

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void low_filter_init(low_filter *v){

     v->Kr = v->FilterTs*1024/(v->FilterTs + v->FilterTf);

     v->Ky = v->FilterTf*1024/(v->FilterTs + v->FilterTf);

}

int16_t low_filter_calc(low_filter *v){

        int32_t tmp = 0;

        tmp = ((int32_t)v->Kr*v->Input + v->Ky*v->Output[1])/1024;

        if(tmp>32767){

                tmp = 32767;

        }

        if( tmp < -32768){

                tmp = -32768;

        }

    v->Output[0] = (int16_t)tmp;

    v->Output[1] = v->Output[0];

        return v->Output[0];

}