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authorTom Rondeau <trondeau@vt.edu>2012-11-10 16:25:30 -0500
committerTom Rondeau <trondeau@vt.edu>2012-11-10 16:25:30 -0500
commitcd8b03e45ff50f6f65f57b2e62e70f725da638d4 (patch)
tree93690515965bdbed800259303cef0051cb7bf609 /gr-analog
parent0cf561018b60bd00b2315f77c7ee073acb6a8758 (diff)
analog: moved lfsr from gr-analog to gr-digital where it is used.
Diffstat (limited to 'gr-analog')
-rw-r--r--gr-analog/include/analog/lfsr.h162
-rwxr-xr-xgr-analog/python/qa_lfsr.py49
-rw-r--r--gr-analog/swig/analog_swig.i2
3 files changed, 0 insertions, 213 deletions
diff --git a/gr-analog/include/analog/lfsr.h b/gr-analog/include/analog/lfsr.h
deleted file mode 100644
index 5cf2ec70df..0000000000
--- a/gr-analog/include/analog/lfsr.h
+++ /dev/null
@@ -1,162 +0,0 @@
-/* -*- 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.
- */
-
-#ifndef INCLUDED_ANALOG_LFSR_H
-#define INCLUDED_ANALOG_LFSR_H
-
-#include <analog/api.h>
-#include <stdexcept>
-#include <stdint.h>
-
-namespace gr {
- namespace analog {
-
- /*!
- * \brief Fibonacci Linear Feedback Shift Register using specified
- * polynomial mask
- * \ingroup misc
- *
- * Generates a maximal length pseudo-random sequence of length
- * 2^degree-1
- *
- * Constructor: analog::lfsr(int mask, int seed, int reg_len);
- *
- * \param mask - polynomial coefficients representing the
- * locations of feedback taps from a shift register
- * which are xor'ed together to form the new high
- * order bit.
- *
- * Some common masks might be:
- * x^4 + x^3 + x^0 = 0x19
- * x^5 + x^3 + x^0 = 0x29
- * x^6 + x^5 + x^0 = 0x61
- *
- * \param seed - the initialization vector placed into the
- * register durring initialization. Low order bit
- * corresponds to x^0 coefficient -- the first to be
- * shifted as output.
- *
- * \param reg_len - specifies the length of the feedback shift
- * register to be used. Durring each iteration, the
- * register is rightshifted one and the new bit is
- * placed in bit reg_len. reg_len should generally be
- * at least order(mask) + 1
- *
- *
- * see http://en.wikipedia.org/wiki/Linear_feedback_shift_register
- * for more explanation.
- *
- * next_bit() - Standard LFSR operation
- *
- * Perform one cycle of the LFSR. The output bit is taken from
- * the shift register LSB. The shift register MSB is assigned from
- * the modulo 2 sum of the masked shift register.
- *
- * next_bit_scramble(unsigned char input) - Scramble an input stream
- *
- * Perform one cycle of the LFSR. The output bit is taken from
- * the shift register LSB. The shift register MSB is assigned from
- * the modulo 2 sum of the masked shift register and the input LSB.
- *
- * next_bit_descramble(unsigned char input) - Descramble an input stream
- *
- * Perform one cycle of the LFSR. The output bit is taken from
- * the modulo 2 sum of the masked shift register and the input LSB.
- * The shift register MSB is assigned from the LSB of the input.
- *
- * See http://en.wikipedia.org/wiki/Scrambler for operation of these
- * last two functions (see multiplicative scrambler.)
- */
- class lfsr
- {
- private:
- uint32_t d_shift_register;
- uint32_t d_mask;
- uint32_t d_seed;
- uint32_t d_shift_register_length; // less than 32
-
- static uint32_t
- popCount(uint32_t x)
- {
- uint32_t r = x - ((x >> 1) & 033333333333)
- - ((x >> 2) & 011111111111);
- return ((r + (r >> 3)) & 030707070707) % 63;
- }
-
- public:
- lfsr(uint32_t mask, uint32_t seed, uint32_t reg_len)
- : d_shift_register(seed),
- d_mask(mask),
- d_seed(seed),
- d_shift_register_length(reg_len)
- {
- if(reg_len > 31)
- throw std::invalid_argument("reg_len must be <= 31");
- }
-
- unsigned char next_bit()
- {
- unsigned char output = d_shift_register & 1;
- unsigned char newbit = popCount( d_shift_register & d_mask )%2;
- d_shift_register = ((d_shift_register>>1) | (newbit<<d_shift_register_length));
- return output;
- }
-
- unsigned char next_bit_scramble(unsigned char input)
- {
- unsigned char output = d_shift_register & 1;
- unsigned char newbit = (popCount( d_shift_register & d_mask )%2)^(input & 1);
- d_shift_register = ((d_shift_register>>1) | (newbit<<d_shift_register_length));
- return output;
- }
-
- unsigned char next_bit_descramble(unsigned char input)
- {
- unsigned char output = (popCount( d_shift_register & d_mask )%2)^(input & 1);
- unsigned char newbit = input & 1;
- d_shift_register = ((d_shift_register>>1) | (newbit<<d_shift_register_length));
- return output;
- }
-
- /*!
- * Reset shift register to initial seed value
- */
- void reset() { d_shift_register = d_seed; }
-
- /*!
- * Rotate the register through x number of bits
- * where we are just throwing away the results to get queued up correctly
- */
- void pre_shift(int num)
- {
- for(int i=0; i<num; i++) {
- next_bit();
- }
- }
-
- int mask() const { return d_mask; }
- };
-
- } /* namespace analog */
-} /* namespace gr */
-
-#endif /* INCLUDED_ANALOG_LFSR_H */
diff --git a/gr-analog/python/qa_lfsr.py b/gr-analog/python/qa_lfsr.py
deleted file mode 100755
index 2a8167a571..0000000000
--- a/gr-analog/python/qa_lfsr.py
+++ /dev/null
@@ -1,49 +0,0 @@
-#!/usr/bin/env python
-#
-# Copyright 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.
-#
-
-from gnuradio import gr, gr_unittest
-import analog_swig as analog
-import math
-
-
-class test_lfsr(gr_unittest.TestCase):
-
- def setUp(self):
- pass
-
- def tearDown(self):
- pass
-
- def test_lfsr_001(self):
- reglen = 8
- l = analog.lfsr(1, 1, reglen)
-
- result_data = []
- for i in xrange(4*(reglen+1)):
- result_data.append(l.next_bit())
-
- expected_result = 4*([1,] + reglen*[0,])
- self.assertFloatTuplesAlmostEqual(expected_result, result_data, 5)
-
-if __name__ == '__main__':
- gr_unittest.run(test_lfsr, "test_lfsr.xml")
-
diff --git a/gr-analog/swig/analog_swig.i b/gr-analog/swig/analog_swig.i
index 016537c949..5171af09bb 100644
--- a/gr-analog/swig/analog_swig.i
+++ b/gr-analog/swig/analog_swig.i
@@ -40,7 +40,6 @@
#include "analog/feedforward_agc_cc.h"
#include "analog/fmdet_cf.h"
#include "analog/frequency_modulator_fc.h"
-#include "analog/lfsr.h"
#include "analog/noise_source_s.h"
#include "analog/noise_source_i.h"
#include "analog/noise_source_f.h"
@@ -79,7 +78,6 @@
%include "analog/feedforward_agc_cc.h"
%include "analog/fmdet_cf.h"
%include "analog/frequency_modulator_fc.h"
-%include "analog/lfsr.h"
%include "analog/noise_source_s.h"
%include "analog/noise_source_i.h"
%include "analog/noise_source_f.h"
generated by cgit v1.2.3 (git 2.39.1) at 2025-03-29 01:22:57 +0000