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[ADSP-21489] IIR Accelarator, change coefficients

Question asked by pereira on Sep 21, 2016
Latest reply on Jan 31, 2017 by pereira

Hi,

I'm playing with the Talkthrough_IIR_Accelerator example for ADSP-21489.

I would like to change the biquad coefficients while running, to dynamically bypass the filter.

 

I did this, in the main file :

 

for (i = 0; 1; i++)

    {

        // The code is running with Low Pass filter for a while

 

        // Then I want to change the filter to bypass
        if(i == 2000)
        {
            coeffs_low_pass[0] = 1.;
            coeffs_low_pass[1] = 0.;
            coeffs_low_pass[2] = 0.;
            coeffs_low_pass[3] = 0.;
            coeffs_low_pass[4] = 0.;
            coeffs_low_pass[7] = 1.;
            coeffs_low_pass[8] = 0.;
            coeffs_low_pass[9] = 0.;
            coeffs_low_pass[10] = 0.;
            coeffs_low_pass[11] = 0.;
            coeffs_low_pass[14] = 1.;
            coeffs_low_pass[15] = 0.;
            coeffs_low_pass[16] = 0.;
            coeffs_low_pass[17] = 0.;
            coeffs_low_pass[18] = 0.;
            coeffs_low_pass[21] = 1.;
        }
       

        //Wait till next block of data received

        while(data_ready==0);

        data_ready=0;

 

        //Process the data received

        process_AD1939_samples();

    }

 

The filter change is not taken... why ?

 

You can try the joined code.

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