diff options
Diffstat (limited to 'gr-digital/lib/digital_glfsr_source_b.cc')
-rw-r--r-- | gr-digital/lib/digital_glfsr_source_b.cc | 86 |
1 files changed, 86 insertions, 0 deletions
diff --git a/gr-digital/lib/digital_glfsr_source_b.cc b/gr-digital/lib/digital_glfsr_source_b.cc new file mode 100644 index 000000000..e557e475a --- /dev/null +++ b/gr-digital/lib/digital_glfsr_source_b.cc @@ -0,0 +1,86 @@ +/* -*- c++ -*- */ +/* + * Copyright 2007,2010,2012 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. + */ + + +#ifdef HAVE_CONFIG_H +#include <config.h> +#endif + +#include <digital_glfsr_source_b.h> +#include <gri_glfsr.h> +#include <gr_io_signature.h> +#include <stdexcept> + +digital_glfsr_source_b_sptr +digital_make_glfsr_source_b(int degree, bool repeat, int mask, int seed) +{ + return gnuradio::get_initial_sptr(new digital_glfsr_source_b + (degree, repeat, mask, seed)); +} + +digital_glfsr_source_b::digital_glfsr_source_b(int degree, bool repeat, + int mask, int seed) + : gr_sync_block ("glfsr_source_b", + gr_make_io_signature (0, 0, 0), + gr_make_io_signature (1, 1, sizeof(unsigned char))), + d_repeat(repeat), + d_index(0) +{ + if (degree < 1 || degree > 32) + throw std::runtime_error("digital_glfsr_source_b: degree must be between 1 and 32 inclusive"); + d_length = (unsigned int)((1ULL << degree)-1); + + if (mask == 0) + mask = gri_glfsr::glfsr_mask(degree); + d_glfsr = new gri_glfsr(mask, seed); +} + +digital_glfsr_source_b::~digital_glfsr_source_b() +{ + delete d_glfsr; +} + +int +digital_glfsr_source_b::work(int noutput_items, + gr_vector_const_void_star &input_items, + gr_vector_void_star &output_items) +{ + char *out = (char *) output_items[0]; + if ((d_index > d_length) && d_repeat == false) + return -1; /* once through the sequence */ + + int i; + for (i = 0; i < noutput_items; i++) { + out[i] = d_glfsr->next_bit(); + d_index++; + if (d_index > d_length && d_repeat == false) + break; + } + + return i; +} + +int +digital_glfsr_source_b::mask() const +{ + return d_glfsr->mask(); +} |