Matching CRC32 from STM32F0 and zlib

Question

I'm working on a communication link between a computer running Linux and a STM32F0. I want to use some kind of error detection for my packets and since the STM32F0 has CRC32 hw and I have zlib with CRC32 on Linux I thought it would be a good idea to use CRC32 for my project. The problem is that I won't get the same CRC value for the same data on the different platforms.

#include <inttypes.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <zlib.h>

int
main(void)
{
  uint8_t byte0 = 0x00;
  uint32_t crc0 = crc32(0L, Z_NULL, 0);
  crc0 = crc32(crc0, &byte0, 1);
  printf("CRC32 value of %" PRIu8 " is: %08" PRIx32 "\n", byte0, crc0);
}

outputs CRC32 value of 0 is: d202ef8d which matches the result on several online calculators.

It seems though that whatever settings I use on the STM32 I can't get the same CRC. I have found a flowchart on how the CRC hw calculates its value in an application note from ST but I can't figure out how it's done in zlib.

Does anyone know if they are compatible?

[edit 1] They both uses the same init value and polynomial.

[edit 2] The STM32 code is relatively uninteresging since it's using the hw.

...
/* Default values are used for init value and polynomial, see edit 1 */
CRC->CR |= CRC_CR_RESET;
CRC->DR = (uint8_t)0x00;
uint32_t crc = CRC->DR;
...

Answer 1

The CRC32 implementation on STM32Fx seems to be not the standard CRC32 implementation you find on many online CRC calculators and the one used in zip.

STM32 implements CRC32-MPEG2 which uses big endian and no final flip mask compared to the zip CRC32 which uses little endian and a final flip mask.

I found this online calculator which supports CRC32-MPEG2.

If you are more interested on other CRC algorithms and their implementation, look at this link.

PS: The HAL driver from STM supports input in byte, half word and word formats and they seem to work fine for STM32F0x in v1.3.1