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Scramble an input stream using an LFSR.

This block works on the LSB only of the input data stream, i.e., on an "unpacked binary" stream, and produces the same format on its output.


Polynomial mask for LFSR
Initial shift register contents
Shift register length

Example Flowgraph[edit]

Insert description of flowgraph here, then show a screenshot of the flowgraph and the output if there is an interesting GUI. Currently we have no standard method of uploading the actual flowgraph to the wiki or git repo, unfortunately. The plan is to have an example flowgraph showing how the block might be used, for every block, and the flowgraphs will live in the git repo.

Here is a simple python-function to create the mask and length from the exponents of a polynomial:

 def make_mask(*exp):
     from functools import reduce
     return reduce(int.__xor__,map(lambda x:2**x,exp)),max(exp)-1
 mask,k = make_mask(5,3,0) # mask and length for p(x) = x^5 + x^3 + 1, a primitive polynomial in GF(2)

Source Files[edit]

C++ files
Header files
Public header files
Block definition