xref: /gem5/src/systemc/tests/systemc/misc/sim_tests/biquad/biquad1/biquad.cpp

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/*****************************************************************************

  biquad.cpp --

  Original Author: Martin Janssen, Synopsys, Inc., 2002-02-15

 *****************************************************************************/

/*****************************************************************************

  MODIFICATION LOG - modifiers, enter your name, affiliation, date and
  changes you are making here.

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/* Filename biquad.cc */
/* This is the implementation file for synchronous process `biquad' */

#include "biquad.h"

void biquad::entry()
{
  float Acc; // Accumulator
  float sample; // Input sample

  if ((bool) reset == true) {
    Del[0] = Del[1] = Del[2] = Del[3] = 0.0;
    out.write(0.0);
    wait();
  }

  while (true) {
    sample = in.read();
    Acc = Cte[0] * sample;
    for (int i = 0; i < 4; i++) {
      Acc += Cte[i+1] * Del[i];
    }
    //    Acc = Acc / 1024.0;
    Del[1] = Del[0]; Del[0] = sample;
    Del[3] = Del[2]; Del[2] = Acc;
    out.write(Acc);
    wait();
  }

} // end of entry function