1 files changed, 104 insertions, 0 deletions
diff --git a/gr-digital/lib/additive_scrambler_bb_impl.cc b/gr-digital/lib/additive_scrambler_bb_impl.cc
new file mode 100644
index 0000000000..8238f2d988
--- /dev/null
+++ b/gr-digital/lib/additive_scrambler_bb_impl.cc
@@ -0,0 +1,104 @@
+/* -*- c++ -*- */
+/*
+ * Copyright 2008,2010,2012 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 "additive_scrambler_bb_impl.h"
+#include <gr_io_signature.h>
+
+namespace gr {
+  namespace digital {
+    
+    additive_scrambler_bb::sptr
+    additive_scrambler_bb::make(int mask, int seed, int len, int count)
+    {
+      return gnuradio::get_initial_sptr(new additive_scrambler_bb_impl
+					(mask, seed, len, count));
+    }
+
+    additive_scrambler_bb_impl::additive_scrambler_bb_impl(int mask,
+							   int seed,
+							   int len,
+							   int count)
+      : gr_sync_block("additive_scrambler_bb",
+		      gr_make_io_signature(1, 1, sizeof(unsigned char)),
+		      gr_make_io_signature(1, 1, sizeof(unsigned char))),
+	d_lfsr(mask, seed, len),
+	d_count(count),
+	d_bits(0), d_len(len), d_seed(seed)
+    {
+    }
+
+    additive_scrambler_bb_impl::~additive_scrambler_bb_impl()
+    {
+    }
+
+    int
+    additive_scrambler_bb_impl::mask() const 
+    { 
+      return d_lfsr.mask();
+    }
+
+    int
+    additive_scrambler_bb_impl::seed() const
+    {
+      return d_seed;
+    }
+
+    int
+    additive_scrambler_bb_impl::len() const
+    {
+      return d_len;
+    }
+
+    int
+    additive_scrambler_bb_impl::count() const
+    {
+      return d_count;
+    }
+
+    int
+    additive_scrambler_bb_impl::work(int noutput_items,
+				     gr_vector_const_void_star &input_items,
+				     gr_vector_void_star &output_items)
+    {
+      const unsigned char *in = (const unsigned char *)input_items[0];
+      unsigned char *out = (unsigned char *)output_items[0];
+
+      for(int i = 0; i < noutput_items; i++) {
+	out[i] = in[i]^d_lfsr.next_bit();
+	if(d_count > 0) {
+	  if(++d_bits == d_count) {
+	    d_lfsr.reset();
+	    d_bits = 0;
+	  }
+	}
+      }
+
+      return noutput_items;
+    }
+
+  } /* namespace digital */
+} /* namespace gr */
+