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hexendiannessfat32

Hexadecimal conversion in FAT32 BIOS parameter block

I am a bit confused, what is the difference between 0x0002 and 0x02. I am trying to understand the FAT boot sector, and I am stuck as I don't understand why these two values are interpreted differently. When I paste both values in a hex to decimal converter it returns 2 in both cases, rightly so.

Why are these values interpreted differently by the operating system, and what is the effect of leading zeros on hexadecimal numbers.

BIOS Parameter Block and Extended BIOS Parameter Block Fields

Solution

  • I just discovered that the values in the FAT are stored in little endian, thus 0x0002 is reverted to 0x0200 which is 512 in base 10. 02 is just 2 in base 10.