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<a href="lfsr_8h.html">Go to the documentation of this file.</a><div class="fragment"><div class="line"><a name="l00001"></a><span class="lineno"> 1</span> <span class="comment">/* -*- c++ -*- */</span></div>
<div class="line"><a name="l00002"></a><span class="lineno"> 2</span> <span class="comment">/*</span></div>
<div class="line"><a name="l00003"></a><span class="lineno"> 3</span> <span class="comment"> * Copyright 2008,2010,2012 Free Software Foundation, Inc.</span></div>
<div class="line"><a name="l00004"></a><span class="lineno"> 4</span> <span class="comment"> *</span></div>
<div class="line"><a name="l00005"></a><span class="lineno"> 5</span> <span class="comment"> * This file is part of GNU Radio</span></div>
<div class="line"><a name="l00006"></a><span class="lineno"> 6</span> <span class="comment"> *</span></div>
<div class="line"><a name="l00007"></a><span class="lineno"> 7</span> <span class="comment"> * GNU Radio is free software; you can redistribute it and/or modify</span></div>
<div class="line"><a name="l00008"></a><span class="lineno"> 8</span> <span class="comment"> * it under the terms of the GNU General Public License as published by</span></div>
<div class="line"><a name="l00009"></a><span class="lineno"> 9</span> <span class="comment"> * the Free Software Foundation; either version 3, or (at your option)</span></div>
<div class="line"><a name="l00010"></a><span class="lineno"> 10</span> <span class="comment"> * any later version.</span></div>
<div class="line"><a name="l00011"></a><span class="lineno"> 11</span> <span class="comment"> *</span></div>
<div class="line"><a name="l00012"></a><span class="lineno"> 12</span> <span class="comment"> * GNU Radio is distributed in the hope that it will be useful,</span></div>
<div class="line"><a name="l00013"></a><span class="lineno"> 13</span> <span class="comment"> * but WITHOUT ANY WARRANTY; without even the implied warranty of</span></div>
<div class="line"><a name="l00014"></a><span class="lineno"> 14</span> <span class="comment"> * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the</span></div>
<div class="line"><a name="l00015"></a><span class="lineno"> 15</span> <span class="comment"> * GNU General Public License for more details.</span></div>
<div class="line"><a name="l00016"></a><span class="lineno"> 16</span> <span class="comment"> *</span></div>
<div class="line"><a name="l00017"></a><span class="lineno"> 17</span> <span class="comment"> * You should have received a copy of the GNU General Public License</span></div>
<div class="line"><a name="l00018"></a><span class="lineno"> 18</span> <span class="comment"> * along with GNU Radio; see the file COPYING. If not, write to</span></div>
<div class="line"><a name="l00019"></a><span class="lineno"> 19</span> <span class="comment"> * the Free Software Foundation, Inc., 51 Franklin Street,</span></div>
<div class="line"><a name="l00020"></a><span class="lineno"> 20</span> <span class="comment"> * Boston, MA 02110-1301, USA.</span></div>
<div class="line"><a name="l00021"></a><span class="lineno"> 21</span> <span class="comment"> */</span></div>
<div class="line"><a name="l00022"></a><span class="lineno"> 22</span> </div>
<div class="line"><a name="l00023"></a><span class="lineno"> 23</span> <span class="preprocessor">#ifndef INCLUDED_ANALOG_LFSR_H</span></div>
<div class="line"><a name="l00024"></a><span class="lineno"> 24</span> <span class="preprocessor"></span><span class="preprocessor">#define INCLUDED_ANALOG_LFSR_H</span></div>
<div class="line"><a name="l00025"></a><span class="lineno"> 25</span> <span class="preprocessor"></span></div>
<div class="line"><a name="l00026"></a><span class="lineno"> 26</span> <span class="preprocessor">#include <<a class="code" href="gr-analog_2include_2analog_2api_8h.html">analog/api.h</a>></span></div>
<div class="line"><a name="l00027"></a><span class="lineno"> 27</span> <span class="preprocessor">#include <stdexcept></span></div>
<div class="line"><a name="l00028"></a><span class="lineno"> 28</span> <span class="preprocessor">#include <<a class="code" href="stdint_8h.html">stdint.h</a>></span></div>
<div class="line"><a name="l00029"></a><span class="lineno"> 29</span> </div>
<div class="line"><a name="l00030"></a><span class="lineno"> 30</span> <span class="keyword">namespace </span>gr {</div>
<div class="line"><a name="l00031"></a><span class="lineno"> 31</span>  <span class="keyword">namespace </span>analog {</div>
<div class="line"><a name="l00032"></a><span class="lineno"> 32</span> <span class="comment"></span></div>
<div class="line"><a name="l00033"></a><span class="lineno"> 33</span> <span class="comment"> /*!</span></div>
<div class="line"><a name="l00034"></a><span class="lineno"> 34</span> <span class="comment"> * \brief Fibonacci Linear Feedback Shift Register using specified</span></div>
<div class="line"><a name="l00035"></a><span class="lineno"> 35</span> <span class="comment"> * polynomial mask</span></div>
<div class="line"><a name="l00036"></a><span class="lineno"> 36</span> <span class="comment"> * \ingroup misc</span></div>
<div class="line"><a name="l00037"></a><span class="lineno"> 37</span> <span class="comment"> *</span></div>
<div class="line"><a name="l00038"></a><span class="lineno"> 38</span> <span class="comment"> * Generates a maximal length pseudo-random sequence of length</span></div>
<div class="line"><a name="l00039"></a><span class="lineno"> 39</span> <span class="comment"> * 2^degree-1</span></div>
<div class="line"><a name="l00040"></a><span class="lineno"> 40</span> <span class="comment"> *</span></div>
<div class="line"><a name="l00041"></a><span class="lineno"> 41</span> <span class="comment"> * Constructor: analog::lfsr(int mask, int seed, int reg_len);</span></div>
<div class="line"><a name="l00042"></a><span class="lineno"> 42</span> <span class="comment"> *</span></div>
<div class="line"><a name="l00043"></a><span class="lineno"> 43</span> <span class="comment"> * \param mask - polynomial coefficients representing the</span></div>
<div class="line"><a name="l00044"></a><span class="lineno"> 44</span> <span class="comment"> * locations of feedback taps from a shift register</span></div>
<div class="line"><a name="l00045"></a><span class="lineno"> 45</span> <span class="comment"> * which are xor'ed together to form the new high</span></div>
<div class="line"><a name="l00046"></a><span class="lineno"> 46</span> <span class="comment"> * order bit.</span></div>
<div class="line"><a name="l00047"></a><span class="lineno"> 47</span> <span class="comment"> *</span></div>
<div class="line"><a name="l00048"></a><span class="lineno"> 48</span> <span class="comment"> * Some common masks might be:</span></div>
<div class="line"><a name="l00049"></a><span class="lineno"> 49</span> <span class="comment"> * x^4 + x^3 + x^0 = 0x19</span></div>
<div class="line"><a name="l00050"></a><span class="lineno"> 50</span> <span class="comment"> * x^5 + x^3 + x^0 = 0x29</span></div>
<div class="line"><a name="l00051"></a><span class="lineno"> 51</span> <span class="comment"> * x^6 + x^5 + x^0 = 0x61</span></div>
<div class="line"><a name="l00052"></a><span class="lineno"> 52</span> <span class="comment"> *</span></div>
<div class="line"><a name="l00053"></a><span class="lineno"> 53</span> <span class="comment"> * \param seed - the initialization vector placed into the</span></div>
<div class="line"><a name="l00054"></a><span class="lineno"> 54</span> <span class="comment"> * register durring initialization. Low order bit</span></div>
<div class="line"><a name="l00055"></a><span class="lineno"> 55</span> <span class="comment"> * corresponds to x^0 coefficient -- the first to be</span></div>
<div class="line"><a name="l00056"></a><span class="lineno"> 56</span> <span class="comment"> * shifted as output.</span></div>
<div class="line"><a name="l00057"></a><span class="lineno"> 57</span> <span class="comment"> *</span></div>
<div class="line"><a name="l00058"></a><span class="lineno"> 58</span> <span class="comment"> * \param reg_len - specifies the length of the feedback shift</span></div>
<div class="line"><a name="l00059"></a><span class="lineno"> 59</span> <span class="comment"> * register to be used. Durring each iteration, the</span></div>
<div class="line"><a name="l00060"></a><span class="lineno"> 60</span> <span class="comment"> * register is rightshifted one and the new bit is</span></div>
<div class="line"><a name="l00061"></a><span class="lineno"> 61</span> <span class="comment"> * placed in bit reg_len. reg_len should generally be</span></div>
<div class="line"><a name="l00062"></a><span class="lineno"> 62</span> <span class="comment"> * at least order(mask) + 1</span></div>
<div class="line"><a name="l00063"></a><span class="lineno"> 63</span> <span class="comment"> *</span></div>
<div class="line"><a name="l00064"></a><span class="lineno"> 64</span> <span class="comment"> *</span></div>
<div class="line"><a name="l00065"></a><span class="lineno"> 65</span> <span class="comment"> * see http://en.wikipedia.org/wiki/Linear_feedback_shift_register</span></div>
<div class="line"><a name="l00066"></a><span class="lineno"> 66</span> <span class="comment"> * for more explanation.</span></div>
<div class="line"><a name="l00067"></a><span class="lineno"> 67</span> <span class="comment"> *</span></div>
<div class="line"><a name="l00068"></a><span class="lineno"> 68</span> <span class="comment"> * next_bit() - Standard LFSR operation</span></div>
<div class="line"><a name="l00069"></a><span class="lineno"> 69</span> <span class="comment"> *</span></div>
<div class="line"><a name="l00070"></a><span class="lineno"> 70</span> <span class="comment"> * Perform one cycle of the LFSR. The output bit is taken from</span></div>
<div class="line"><a name="l00071"></a><span class="lineno"> 71</span> <span class="comment"> * the shift register LSB. The shift register MSB is assigned from</span></div>
<div class="line"><a name="l00072"></a><span class="lineno"> 72</span> <span class="comment"> * the modulo 2 sum of the masked shift register.</span></div>
<div class="line"><a name="l00073"></a><span class="lineno"> 73</span> <span class="comment"> *</span></div>
<div class="line"><a name="l00074"></a><span class="lineno"> 74</span> <span class="comment"> * next_bit_scramble(unsigned char input) - Scramble an input stream</span></div>
<div class="line"><a name="l00075"></a><span class="lineno"> 75</span> <span class="comment"> *</span></div>
<div class="line"><a name="l00076"></a><span class="lineno"> 76</span> <span class="comment"> * Perform one cycle of the LFSR. The output bit is taken from</span></div>
<div class="line"><a name="l00077"></a><span class="lineno"> 77</span> <span class="comment"> * the shift register LSB. The shift register MSB is assigned from</span></div>
<div class="line"><a name="l00078"></a><span class="lineno"> 78</span> <span class="comment"> * the modulo 2 sum of the masked shift register and the input LSB.</span></div>
<div class="line"><a name="l00079"></a><span class="lineno"> 79</span> <span class="comment"> *</span></div>
<div class="line"><a name="l00080"></a><span class="lineno"> 80</span> <span class="comment"> * next_bit_descramble(unsigned char input) - Descramble an input stream</span></div>
<div class="line"><a name="l00081"></a><span class="lineno"> 81</span> <span class="comment"> *</span></div>
<div class="line"><a name="l00082"></a><span class="lineno"> 82</span> <span class="comment"> * Perform one cycle of the LFSR. The output bit is taken from</span></div>
<div class="line"><a name="l00083"></a><span class="lineno"> 83</span> <span class="comment"> * the modulo 2 sum of the masked shift register and the input LSB.</span></div>
<div class="line"><a name="l00084"></a><span class="lineno"> 84</span> <span class="comment"> * The shift register MSB is assigned from the LSB of the input.</span></div>
<div class="line"><a name="l00085"></a><span class="lineno"> 85</span> <span class="comment"> *</span></div>
<div class="line"><a name="l00086"></a><span class="lineno"> 86</span> <span class="comment"> * See http://en.wikipedia.org/wiki/Scrambler for operation of these</span></div>
<div class="line"><a name="l00087"></a><span class="lineno"> 87</span> <span class="comment"> * last two functions (see multiplicative scrambler.)</span></div>
<div class="line"><a name="l00088"></a><span class="lineno"> 88</span> <span class="comment"> */</span></div>
<div class="line"><a name="l00089"></a><span class="lineno"><a class="code" href="classgr_1_1analog_1_1lfsr.html"> 89</a></span>  <span class="keyword">class </span><a class="code" href="classgr_1_1analog_1_1lfsr.html" title="Fibonacci Linear Feedback Shift Register using specified polynomial maskGenerates a maximal length ps...">lfsr</a></div>
<div class="line"><a name="l00090"></a><span class="lineno"> 90</span>  {</div>
<div class="line"><a name="l00091"></a><span class="lineno"> 91</span>  <span class="keyword">private</span>:</div>
<div class="line"><a name="l00092"></a><span class="lineno"> 92</span>  <a class="code" href="stdint_8h.html#a435d1572bf3f880d55459d9805097f62">uint32_t</a> d_shift_register;</div>
<div class="line"><a name="l00093"></a><span class="lineno"> 93</span>  <a class="code" href="stdint_8h.html#a435d1572bf3f880d55459d9805097f62">uint32_t</a> d_mask;</div>
<div class="line"><a name="l00094"></a><span class="lineno"> 94</span>  <a class="code" href="stdint_8h.html#a435d1572bf3f880d55459d9805097f62">uint32_t</a> d_seed;</div>
<div class="line"><a name="l00095"></a><span class="lineno"> 95</span>  <a class="code" href="stdint_8h.html#a435d1572bf3f880d55459d9805097f62">uint32_t</a> d_shift_register_length; <span class="comment">// less than 32</span></div>
<div class="line"><a name="l00096"></a><span class="lineno"> 96</span> </div>
<div class="line"><a name="l00097"></a><span class="lineno"> 97</span>  <span class="keyword">static</span> <a class="code" href="stdint_8h.html#a435d1572bf3f880d55459d9805097f62">uint32_t</a></div>
<div class="line"><a name="l00098"></a><span class="lineno"> 98</span>  popCount(<a class="code" href="stdint_8h.html#a435d1572bf3f880d55459d9805097f62">uint32_t</a> x)</div>
<div class="line"><a name="l00099"></a><span class="lineno"> 99</span>  {</div>
<div class="line"><a name="l00100"></a><span class="lineno"> 100</span>  <a class="code" href="stdint_8h.html#a435d1572bf3f880d55459d9805097f62">uint32_t</a> r = x - ((x >> 1) & 033333333333)</div>
<div class="line"><a name="l00101"></a><span class="lineno"> 101</span>  - ((x >> 2) & 011111111111);</div>
<div class="line"><a name="l00102"></a><span class="lineno"> 102</span>  <span class="keywordflow">return</span> ((r + (r >> 3)) & 030707070707) % 63;</div>
<div class="line"><a name="l00103"></a><span class="lineno"> 103</span>  }</div>
<div class="line"><a name="l00104"></a><span class="lineno"> 104</span> </div>
<div class="line"><a name="l00105"></a><span class="lineno"> 105</span>  <span class="keyword">public</span>:</div>
<div class="line"><a name="l00106"></a><span class="lineno"><a class="code" href="classgr_1_1analog_1_1lfsr.html#a020534809c77f796f0b1ba31bca2a001"> 106</a></span>  <a class="code" href="classgr_1_1analog_1_1lfsr.html#a020534809c77f796f0b1ba31bca2a001">lfsr</a>(<a class="code" href="stdint_8h.html#a435d1572bf3f880d55459d9805097f62">uint32_t</a> <a class="code" href="classgr_1_1analog_1_1lfsr.html#a79298d93a2b55146f701e65870316b2c">mask</a>, <a class="code" href="stdint_8h.html#a435d1572bf3f880d55459d9805097f62">uint32_t</a> seed, <a class="code" href="stdint_8h.html#a435d1572bf3f880d55459d9805097f62">uint32_t</a> reg_len)</div>
<div class="line"><a name="l00107"></a><span class="lineno"> 107</span>  : d_shift_register(seed),</div>
<div class="line"><a name="l00108"></a><span class="lineno"> 108</span>  d_mask(mask),</div>
<div class="line"><a name="l00109"></a><span class="lineno"> 109</span>  d_seed(seed),</div>
<div class="line"><a name="l00110"></a><span class="lineno"> 110</span>  d_shift_register_length(reg_len)</div>
<div class="line"><a name="l00111"></a><span class="lineno"> 111</span>  {</div>
<div class="line"><a name="l00112"></a><span class="lineno"> 112</span>  <span class="keywordflow">if</span>(reg_len > 31)</div>
<div class="line"><a name="l00113"></a><span class="lineno"> 113</span>  <span class="keywordflow">throw</span> std::invalid_argument(<span class="stringliteral">"reg_len must be <= 31"</span>);</div>
<div class="line"><a name="l00114"></a><span class="lineno"> 114</span>  }</div>
<div class="line"><a name="l00115"></a><span class="lineno"> 115</span> </div>
<div class="line"><a name="l00116"></a><span class="lineno"><a class="code" href="classgr_1_1analog_1_1lfsr.html#a473d4e2fd9422486fa8e7e825ad8c8e4"> 116</a></span>  <span class="keywordtype">unsigned</span> <span class="keywordtype">char</span> <a class="code" href="classgr_1_1analog_1_1lfsr.html#a473d4e2fd9422486fa8e7e825ad8c8e4">next_bit</a>()</div>
<div class="line"><a name="l00117"></a><span class="lineno"> 117</span>  {</div>
<div class="line"><a name="l00118"></a><span class="lineno"> 118</span>  <span class="keywordtype">unsigned</span> <span class="keywordtype">char</span> output = d_shift_register & 1;</div>
<div class="line"><a name="l00119"></a><span class="lineno"> 119</span>  <span class="keywordtype">unsigned</span> <span class="keywordtype">char</span> newbit = popCount( d_shift_register & d_mask )%2;</div>
<div class="line"><a name="l00120"></a><span class="lineno"> 120</span>  d_shift_register = ((d_shift_register>>1) | (newbit<<d_shift_register_length));</div>
<div class="line"><a name="l00121"></a><span class="lineno"> 121</span>  <span class="keywordflow">return</span> output;</div>
<div class="line"><a name="l00122"></a><span class="lineno"> 122</span>  }</div>
<div class="line"><a name="l00123"></a><span class="lineno"> 123</span> </div>
<div class="line"><a name="l00124"></a><span class="lineno"><a class="code" href="classgr_1_1analog_1_1lfsr.html#a31dfc404ba747404a982e4674b6c38fe"> 124</a></span>  <span class="keywordtype">unsigned</span> <span class="keywordtype">char</span> <a class="code" href="classgr_1_1analog_1_1lfsr.html#a31dfc404ba747404a982e4674b6c38fe">next_bit_scramble</a>(<span class="keywordtype">unsigned</span> <span class="keywordtype">char</span> input)</div>
<div class="line"><a name="l00125"></a><span class="lineno"> 125</span>  {</div>
<div class="line"><a name="l00126"></a><span class="lineno"> 126</span>  <span class="keywordtype">unsigned</span> <span class="keywordtype">char</span> output = d_shift_register & 1;</div>
<div class="line"><a name="l00127"></a><span class="lineno"> 127</span>  <span class="keywordtype">unsigned</span> <span class="keywordtype">char</span> newbit = (popCount( d_shift_register & d_mask )%2)^(input & 1);</div>
<div class="line"><a name="l00128"></a><span class="lineno"> 128</span>  d_shift_register = ((d_shift_register>>1) | (newbit<<d_shift_register_length));</div>
<div class="line"><a name="l00129"></a><span class="lineno"> 129</span>  <span class="keywordflow">return</span> output;</div>
<div class="line"><a name="l00130"></a><span class="lineno"> 130</span>  }</div>
<div class="line"><a name="l00131"></a><span class="lineno"> 131</span> </div>
<div class="line"><a name="l00132"></a><span class="lineno"><a class="code" href="classgr_1_1analog_1_1lfsr.html#a11fd6a4c5c2305a448f7469613e300e6"> 132</a></span>  <span class="keywordtype">unsigned</span> <span class="keywordtype">char</span> <a class="code" href="classgr_1_1analog_1_1lfsr.html#a11fd6a4c5c2305a448f7469613e300e6">next_bit_descramble</a>(<span class="keywordtype">unsigned</span> <span class="keywordtype">char</span> input)</div>
<div class="line"><a name="l00133"></a><span class="lineno"> 133</span>  {</div>
<div class="line"><a name="l00134"></a><span class="lineno"> 134</span>  <span class="keywordtype">unsigned</span> <span class="keywordtype">char</span> output = (popCount( d_shift_register & d_mask )%2)^(input & 1);</div>
<div class="line"><a name="l00135"></a><span class="lineno"> 135</span>  <span class="keywordtype">unsigned</span> <span class="keywordtype">char</span> newbit = input & 1;</div>
<div class="line"><a name="l00136"></a><span class="lineno"> 136</span>  d_shift_register = ((d_shift_register>>1) | (newbit<<d_shift_register_length));</div>
<div class="line"><a name="l00137"></a><span class="lineno"> 137</span>  <span class="keywordflow">return</span> output;</div>
<div class="line"><a name="l00138"></a><span class="lineno"> 138</span>  }</div>
<div class="line"><a name="l00139"></a><span class="lineno"> 139</span> <span class="comment"></span></div>
<div class="line"><a name="l00140"></a><span class="lineno"> 140</span> <span class="comment"> /*!</span></div>
<div class="line"><a name="l00141"></a><span class="lineno"> 141</span> <span class="comment"> * Reset shift register to initial seed value</span></div>
<div class="line"><a name="l00142"></a><span class="lineno"> 142</span> <span class="comment"> */</span></div>
<div class="line"><a name="l00143"></a><span class="lineno"><a class="code" href="classgr_1_1analog_1_1lfsr.html#a06fefe2df0e652dd7cac9657a9b2ebad"> 143</a></span>  <span class="keywordtype">void</span> <a class="code" href="classgr_1_1analog_1_1lfsr.html#a06fefe2df0e652dd7cac9657a9b2ebad">reset</a>() { d_shift_register = d_seed; }</div>
<div class="line"><a name="l00144"></a><span class="lineno"> 144</span> <span class="comment"></span></div>
<div class="line"><a name="l00145"></a><span class="lineno"> 145</span> <span class="comment"> /*!</span></div>
<div class="line"><a name="l00146"></a><span class="lineno"> 146</span> <span class="comment"> * Rotate the register through x number of bits</span></div>
<div class="line"><a name="l00147"></a><span class="lineno"> 147</span> <span class="comment"> * where we are just throwing away the results to get queued up correctly</span></div>
<div class="line"><a name="l00148"></a><span class="lineno"> 148</span> <span class="comment"> */</span></div>
<div class="line"><a name="l00149"></a><span class="lineno"><a class="code" href="classgr_1_1analog_1_1lfsr.html#a0bb7e05f6d6bf6f815251148ca25847d"> 149</a></span>  <span class="keywordtype">void</span> <a class="code" href="classgr_1_1analog_1_1lfsr.html#a0bb7e05f6d6bf6f815251148ca25847d">pre_shift</a>(<span class="keywordtype">int</span> num)</div>
<div class="line"><a name="l00150"></a><span class="lineno"> 150</span>  {</div>
<div class="line"><a name="l00151"></a><span class="lineno"> 151</span>  <span class="keywordflow">for</span>(<span class="keywordtype">int</span> i=0; i<num; i++) {</div>
<div class="line"><a name="l00152"></a><span class="lineno"> 152</span>  <a class="code" href="classgr_1_1analog_1_1lfsr.html#a473d4e2fd9422486fa8e7e825ad8c8e4">next_bit</a>();</div>
<div class="line"><a name="l00153"></a><span class="lineno"> 153</span>  }</div>
<div class="line"><a name="l00154"></a><span class="lineno"> 154</span>  }</div>
<div class="line"><a name="l00155"></a><span class="lineno"> 155</span> </div>
<div class="line"><a name="l00156"></a><span class="lineno"><a class="code" href="classgr_1_1analog_1_1lfsr.html#a79298d93a2b55146f701e65870316b2c"> 156</a></span>  <span class="keywordtype">int</span> <a class="code" href="classgr_1_1analog_1_1lfsr.html#a79298d93a2b55146f701e65870316b2c">mask</a>()<span class="keyword"> const </span>{ <span class="keywordflow">return</span> d_mask; }</div>
<div class="line"><a name="l00157"></a><span class="lineno"> 157</span>  };</div>
<div class="line"><a name="l00158"></a><span class="lineno"> 158</span> </div>
<div class="line"><a name="l00159"></a><span class="lineno"> 159</span>  } <span class="comment">/* namespace analog */</span></div>
<div class="line"><a name="l00160"></a><span class="lineno"> 160</span> } <span class="comment">/* namespace gr */</span></div>
<div class="line"><a name="l00161"></a><span class="lineno"> 161</span> </div>
<div class="line"><a name="l00162"></a><span class="lineno"> 162</span> <span class="preprocessor">#endif </span><span class="comment">/* INCLUDED_ANALOG_LFSR_H */</span><span class="preprocessor"></span></div>
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