Tool for calculating exFAT DirectoryEntry checksum
./exfat_directory_entry_checksum.py test_entry.bin
checksum in decimal: 26241
checksum in hex: 0x6681
checksum in hex (swapped): 0x8166
Values from the given data (offset 0x02 and 0x03): 0x81 0x66
Checksum OK
./exfat_directory_entry_checksum.py test_entry2_modded.bin
checksum in decimal: 4481
checksum in hex: 0x1181
checksum in hex (swapped): 0x8111
Values from the given data (offset 0x02 and 0x03): 0x81 0x66
Checksum NOT OK