I need to reproduce the output of a hardware CRC calculator for testing purposes. It is set up for ethernet CRC 32, in trace32 format: /CRC 32. 0x04C11DB7 1 1 0FFFFFFFF 0FFFFFFFF (checksum width, polynom, input reflection, output reflection, crc init, final XOR)
If I feed it values where the 4 bytes are equal (e.g 0x12121212 as each byte being 0x12), the output will match what I calculate using CRC32 or python.
However if I feed it any value where the 4 bytes are not equal, the results are off. For example 0x12341234 will return 0x093c454b (should be 0xa1768922).
Or 0x12345678 will return 0xAF6D87D2 (should be 0x4a090e98).
In the HW I can only select the init value and the polynomial, beyond feeding it 4 bytes to calculate. Rolling calculations(multiple words worth) behave the same way, the output is correct as long as each word fed to it has all bytes the same. Anything else, the output is off.
I am not too knowledgeable about CRC32 and has run out of ideas. Any pointers would be appreciated, what am I doing wrong here? I have double checked the polynomial, but if that was wrong, I could only get the right results extremely rarely, right?
Thank you!
