SEm/escapeLab/LFSR
From FSI
Revision as of 14:56, 5 May 2022 by Axel.amand (Talk | contribs)
|
Welcome to the SEM escape lab
1st Key
Finding the feedback terms of an LFSR
The aim of this task is to find the proper feedback function of an LFSR within a remote control emitter.
Specifications
A system comprising an RF emitter and a receiver allows to transmit a button press. When the emitter is powered via USB, it continuously sends the output bit of a 4-bit Galois LFSR. The receiver is connected to an FPGA board and a LED is switched on when the proper code is received.
The position of the LFSR XOR feed-in taps has to be found in order to match to the receiver. The LFSR polynomial is considered as a 4-bit binary number, which is the value to find.
An USB stick holds the structure of the VHDL and Microsemi deisgn environment.