/* -*- c++ -*- */

/*

 * Copyright 2004 Free Software Foundation, Inc.

 * 

 * This file is part of GNU Radio

 * 

 * GNU Radio is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by

 * the Free Software Foundation; either version 3, or (at your option)

 * any later version.

 * 

 * GNU Radio is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 * 

 * You should have received a copy of the GNU General Public License

 * along with GNU Radio; see the file COPYING.  If not, write to

 * the Free Software Foundation, Inc., 51 Franklin Street,

 * Boston, MA 02110-1301, USA.

 */

#ifndef INCLUDED_GRI_LFSR_32k_H

#define INCLUDED_GRI_LFSR_32k_H

#include <gri_lfsr_15_1_0.h>

/*!

 * \brief generate pseudo-random sequence of length 32768 bits.

 * \ingroup misc

 *

 * This is based on gri_lfsr_15_1_0 with an extra 0 added at the end

 * of the sequence.

 */

class gri_lfsr_32k {

  gri_lfsr_15_1_0        d_lfsr;

  unsigned int                d_count;

 public:

  gri_lfsr_32k () { reset (); }

  void reset (){

    d_lfsr.reset ();

    d_count = 0;

  }

  int next_bit (){

    if (d_count == 32767){

      d_count = 0;

      return 0;

    }

    d_count++;

    return d_lfsr.next_bit ();

  }

  int next_byte (){

    int        v = 0;

    for (int i = 0; i < 8; i++){

      v >>= 1;

      if (next_bit ())

        v |= 0x80;

    }

    return v;

  }

  int next_short (){

    int        v = 0;

    for (int i = 0; i < 16; i++){

      v >>= 1;

      if (next_bit ())

        v |= 0x8000;

    }

    return v;

  }

};

#endif /* INCLUDED_GRI_LFSR_32k_H */