BenQ firmware (technical question)

Hi!

I’ve been wondering how the embedded checksum in the BenQ (and OEM) firmwares is calculated. E.g. for the BLSB firmware the checksum is 0xF4 0x7E 0x E7 0x83. For CVTs these are the last 4 bytes. For .exe files this checksum is just before the length value (also a 4 byte value which for BSLB is 0x00 0x80 0x0e 0x00, meaning that the firmware code as such has the length of 0xE8000 bytes).

However, as much as I’ve tinkered with the data I cannot get e.g. a CRC32 checksum to match.

Someone with more info on the subject?

Regards and TIA,
az