gr-baz Package
digital_glfsr_source_b.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,
20  * Boston, MA 02110-1301, USA.
21  */
22 
23 #ifndef INCLUDED_GR_GLFSR_SOURCE_B_H
24 #define INCLUDED_GR_GLFSR_SOURCE_B_H
25 
26 #include <digital_api.h>
27 #include <gr_sync_block.h>
28 
29 class gri_glfsr;
30 
33 
35 digital_make_glfsr_source_b(int degree, bool repeat=true,
36  int mask=0, int seed=1);
37 
38 /*!
39  * \brief Galois LFSR pseudo-random source
40  * \ingroup source_blk
41  *
42  * \param degree Degree of shift register must be in [1, 32]. If mask
43  * is 0, the degree determines a default mask (see
44  * digital_impl_glfsr.cc for the mapping).
45  * \param repeat Set to repeat sequence.
46  * \param mask Allows a user-defined bit mask for indexes of the shift
47  * register to feed back.
48  * \param seed Initial setting for values in shift register.
49  */
51 {
52  private:
54  digital_make_glfsr_source_b(int degree, bool repeat,
55  int mask, int seed);
56 
57  gri_glfsr *d_glfsr;
58 
59  bool d_repeat;
60  unsigned int d_index;
61  unsigned int d_length;
62 
63  digital_glfsr_source_b(int degree, bool repeat,
64  int mask, int seed);
65 
66  public:
67 
69 
70  int work(int noutput_items,
71  gr_vector_const_void_star &input_items,
72  gr_vector_void_star &output_items);
73 
74  unsigned int period() const { return d_length; }
75  int mask() const;
76 };
77 
78 #endif /* INCLUDED_GR_GLFSR_SOURCE_B_H */