3 * Copyright 2007 Free Software Foundation, Inc.
5 * This file is part of GNU Radio
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)
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.
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.
28 #include <gr_glfsr_source_b.h>
29 #include <gri_glfsr.h>
30 #include <gr_io_signature.h>
33 gr_glfsr_source_b_sptr
34 gr_make_glfsr_source_b(int degree, bool repeat, int mask, int seed)
36 return gr_glfsr_source_b_sptr(new gr_glfsr_source_b(degree, repeat, mask, seed));
39 gr_glfsr_source_b::gr_glfsr_source_b(int degree, bool repeat, int mask, int seed)
40 : gr_sync_block ("glfsr_source_b",
41 gr_make_io_signature (0, 0, 0),
42 gr_make_io_signature (1, 1, sizeof(unsigned char))),
46 if (degree < 1 || degree > 32)
47 throw std::runtime_error("gr_glfsr_source_b: degree must be between 1 and 32 inclusive");
48 d_length = (unsigned int)((1ULL << degree)-1);
51 mask = gri_glfsr::glfsr_mask(degree);
52 d_glfsr = new gri_glfsr(mask, seed);
55 gr_glfsr_source_b::~gr_glfsr_source_b()
61 gr_glfsr_source_b::work(int noutput_items,
62 gr_vector_const_void_star &input_items,
63 gr_vector_void_star &output_items)
65 char *out = (char *) output_items[0];
66 if ((d_index > d_length) && d_repeat == false)
67 return -1; /* once through the sequence */
70 for (i = 0; i < noutput_items; i++) {
71 out[i] = d_glfsr->next_bit();
73 if (d_index > d_length && d_repeat == false)
81 gr_glfsr_source_b::mask() const
83 return d_glfsr->mask();