Cyclic Redundancy Check function

Hello, I tried writing two functions to perform CRC, one for a sender and the other for a receiver.

The reference I used is the CRC example on Matlab website: Perform Cyclic Redundancy Check - MATLAB & Simulink - MathWorks United Kingdom

I attatched 4 files, the file called 'FullCode' has the whole code that performs the CRC for sender and receiver.

'crcSend' is the function that reads the data that has to be transmitted from a text file and generates the required CRC code.

'crcReceive' is the function that verifies whether the data transmitted is correct or not.

'message.txt' has the binary data.

I am unsure why when running crcReceive, I am getting that the remainder is not equal to zero, which means a data transmission error has ocurred, even though the code is equal to the code in 'FullCode', which when running, does give me remainder = 0 and hence no data transmission error.

Appreciate any insight on this.

Answer 1

[Askic V]

As far as I can see, crcreceive.m is missing a portion of code present in the FullCode

divisor = bitshift(divisor,messageLength-divisorDegree-1);
dec2bin(divisor)

divisor = bitshift(divisor,divisorDegree);
dec2bin(divisor)

That is why divisor variable has different values in for loop in FullCode comparing to the for loop in crcReceive.m file.

So, naturally, the results would be different.