40 lines
1.0 KiB
Python
40 lines
1.0 KiB
Python
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#!/usr/bin/env python3
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class lfsr(object):
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def __init__(self, state, taps):
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self.state = state
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self.taps = taps
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# getters and setters (private attributes)
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def get_state(self):
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return self.__state
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def set_state(self, value):
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self.__state = value
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state = property(fget=get_state, fset=set_state, doc="lfsr state (current bits value in lfsr)")
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def get_taps(self):
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return self.__taps
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def set_taps(self, valeur):
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self.__taps = valeur
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taps = property(fget=get_taps, fset=set_taps, doc="lfsr taps (bit positions affecting next state)")
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def shift(self):
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'''
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calculate next state and return the output bit
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'''
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feedback = sum(self.state[tap] for tap in self.taps) % 2
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output = self.state[-1]
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self.state = [feedback] + self.state[:-1]
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return output
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key=[0]*16
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key.append(1)
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taps = [16-0, 16-14]
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lfsr17 = lfsr(key, taps)
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# Generate 100 bits
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for _ in range(100):
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print(lfsr17.shift(), end=' ')
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