GNU Radio Manual and C++ API Reference  3.7.9.2
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glfsr.h
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1 /* -*- c++ -*- */
2 /*
3  * Copyright 2007,2012 Free Software Foundation, Inc.
4  *
5  * This file is part of GNU Radio
6  *
7  * GNU Radio is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 3, or (at your option)
10  * any later version.
11  *
12  * GNU Radio is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15  * GNU General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License
18  * along with GNU Radio; see the file COPYING. If not, write to
19  * the Free Software Foundation, Inc., 51 Franklin Street,
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21  */
22 
23 #ifndef INCLUDED_DIGITAL_GLFSR_H
24 #define INCLUDED_DIGITAL_GLFSR_H
25 
26 #include <gnuradio/digital/api.h>
27 
28 namespace gr {
29  namespace digital {
30 
31  /*!
32  * \brief Galois Linear Feedback Shift Register using specified polynomial mask
33  * \ingroup waveform_generators_blk
34  *
35  * \details
36  * Generates a maximal length pseudo-random sequence of length 2^degree-1
37  */
39  {
40  private:
41  int d_shift_register;
42  int d_mask;
43 
44  public:
45  glfsr(int mask, int seed) { d_shift_register = seed; d_mask = mask; }
46  ~glfsr();
47 
48  static int glfsr_mask(int degree);
49 
50  unsigned char next_bit()
51  {
52  unsigned char bit = d_shift_register & 1;
53  d_shift_register >>= 1;
54  if(bit)
55  d_shift_register ^= d_mask;
56  return bit;
57  }
58 
59  int mask() const { return d_mask; }
60  };
61 
62  } /* namespace digital */
63 } /* namespace gr */
64 
65 #endif /* INCLUDED_DIGITAL_GLFSR_H */
int mask() const
Definition: glfsr.h:59
#define DIGITAL_API
Definition: gr-digital/include/gnuradio/digital/api.h:30
glfsr(int mask, int seed)
Definition: glfsr.h:45
Galois Linear Feedback Shift Register using specified polynomial mask.
Definition: glfsr.h:38
Include this header to use the message passing features.
Definition: logger.h:131
unsigned char next_bit()
Definition: glfsr.h:50