Whats with embedded devs and coming up with weird new ways to calculate a checksum.
Today I found through trial and error the checksum for a UART message protocol:

checksum = (0x08 - byte[5]) & 0xFF

Did they just roll a dice on this or smth

@timonsku that screams buggy implementation lol
@gsuberland tbf it seems like only byte 5 out of 8 ever changes lol
@timonsku Only byte[5] paid for protection.
@timonsku hardly even a check sum at that point ​