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Questions tagged [lfsr]

From Wikipedia: "In computing, a linear-feedback shift register (LFSR) is a shift register whose input bit is a linear function of its previous state."

For more information see: https://en.wikipedia.org/wiki/Linear-feedback_shift_register

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random number using LFSR

I am a little new to this subject. Initial idea is to generate a random number using a LFSR. So far I have developed a LFSR method using c#. Once the function is called it returns the same value all the time. What I have to change in order to…
kuma DK
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Is it always true that the CRC of a buffer that has the CRC appended to the end is always 0?

Example of the hypothesis... Is it always true that the CRC of a buffer that has the CRC appended to the end is always 0? extern uint16_t CRC16(uint_8* buffer, uint16_t size); // From your favorite library void main() { uint16_t crc; …
Larry_C
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NASM x86 core dump writing on memory

I am learning assembly NASM and trying to do a LFSR code and call it on a C program to evaluate the execution time diference, but failed to figure out the problem with my code. My LFSR C version works just fine and is defined as follows: int…
Skalwalker
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Linear feedback shift register is not even distrubtion

I did write a really simple C like code for a linear feedbackpack shift register within an array of booleans based on following…
xc3s50an
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is it correct that for a nbit LFSR (galois algorithm in particular) the maximum number of unique 32byte keys can only be 255?

In fact I have more than just the one question as I try to better understand the whole topic. for a CTF challenge I am currently reading up on LSFR. The code the challenge provides as an example is a 5bit lsfr and it generates from its bit sequences…
Zapho Oxx
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Reading .bin or .dat file in Python

I am generating a binary file. I opened it using hexdump, it looks like this below enter image description here But when I try to read this file in python using file = open("lfsr.bin","rb") data = file.read(10) print data It's printing blank/empty…
Yaaseen Mohamed
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Linear Feedback Shift Register: Tapping 1 bit

In an xor lfsr, the bit to be shifted in is the xor of all the tapped bits. But if you tap only 1 bit, does that mean 0 is always the bit that is shifted in, since the 1 bit that is tapped is xor'ed with itself? Thanks
A is for Ambition
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Pseudo Random Number Generator using LFSR in VHDL

I'm having a bit of trouble creating a prng using the lfsr method. Here is my code: library IEEE; use IEEE.STD_LOGIC_1164.ALL; entity pseudorng is Port ( clock : in STD_LOGIC; reset : in STD_LOGIC; Q : out STD_LOGIC_VECTOR (7 downto…
user7782529
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How to generate random numbers in FPGA for use as IV in cryptographic applications

I am looking for a way to generate random numbers in FPGA for use as an IV for cryptographic applications. However, the answers to similar questions i found on Stackoverflow so far generate random numbers from a "Fixed SEED" which is not at all…
Kaka
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64 bit LFSR design

I have designed a 64 bit lfsr but I think its not showing random. Its kind of regular pattern. Can anyone please check my code and see if its correct. (TAP 64,63,61,60) module lfsr (out, clk, rst); output reg [63:0] out; input clk, rst; wire…
Emily Blake
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64 bit LFSR output in verilog

I am trying to get 64 bit output from an LFSR. I found a code in the net and edited it for 64 bit. But I am not getting the output. module LFSR8_8E(reset_, clock, q, lfsr_to); input clock, reset_; output [63:0] q, lfsr_to; reg…
Emily Blake
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LFSR code is giving wrong result

I have the code for LFSR and getting wrong results, the first 8 bits should be 01110010 but i'm getting 0101111001. I'm talking about Galois LSFR: en.wikipedia.org/wiki/Linear-feedback_shift_register Can anyone see what the problem is with this…
neX
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