1 files changed, 86 insertions, 0 deletions
diff --git a/gr-digital/lib/digital_glfsr_source_f.cc b/gr-digital/lib/digital_glfsr_source_f.cc
new file mode 100644
index 000000000..5a7736ef8
--- /dev/null
+++ b/gr-digital/lib/digital_glfsr_source_f.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_f.h>
+#include <gri_glfsr.h>
+#include <gr_io_signature.h>
+#include <stdexcept>
+
+digital_glfsr_source_f_sptr
+digital_make_glfsr_source_f(int degree, bool repeat, int mask, int seed)
+{
+  return gnuradio::get_initial_sptr(new digital_glfsr_source_f
+				    (degree, repeat, mask, seed));
+}
+
+digital_glfsr_source_f::digital_glfsr_source_f(int degree, bool repeat,
+					       int mask, int seed)
+  : gr_sync_block ("glfsr_source_f",
+		   gr_make_io_signature (0, 0, 0),
+		   gr_make_io_signature (1, 1, sizeof(float))),
+    d_repeat(repeat),
+    d_index(0)
+{
+  if (degree < 1 || degree > 32)
+    throw std::runtime_error("digital_glfsr_source_f: 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_f::~digital_glfsr_source_f()
+{
+  delete d_glfsr;
+}
+
+int
+digital_glfsr_source_f::work(int noutput_items,
+			     gr_vector_const_void_star &input_items,
+			     gr_vector_void_star &output_items)
+{
+  float *out = (float *) 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] = (float)d_glfsr->next_bit()*2.0-1.0;
+    d_index++;
+    if (d_index > d_length && d_repeat == false)
+      break;
+  }
+
+  return i;
+}
+
+int
+digital_glfsr_source_f::mask() const
+{
+  return d_glfsr->mask();
+}