Network, Computer and Programming Resources
Boot Sector and BPB Structure[Fat12 and Fat16]-> BS_BootSig [Offset=38, Size=1]Boot Sector and BPB Structure[Fat12 and Fat16]-> BS_DrvNum [Offset=36, Size=1]Boot Sector and BPB Structure[Fat12 and Fat16]-> BS_FilSysType [Offset=54, Size=8]Boot Sector and BPB Structure[Fat12 and Fat16]-> BS_Reserved1 [Offset=37, Size=1]Boot Sector and BPB Structure[Fat12 and Fat16]-> BS_VolID [Offset=39, Size=4]Boot Sector and BPB Structure[Fat12 and Fat16]-> BS_VolLab [Offset=43, Size=11]Boot Sector and BPB Structure[Fat32]-> BPB_BkBootSec [Offset=50, Size=2]Boot Sector and BPB Structure[Fat32]-> BPB_ExtFlags [Offset=40, Size=2]Boot Sector and BPB Structure[Fat32]-> BPB_FATSz32 [Offset=36, Size=4]Boot Sector and BPB Structure[Fat32]-> BPB_FSInfo [Offset=48, Size=2]Boot Sector and BPB Structure[Fat32]-> BPB_FSVer [Offset=42, Size=2]Boot Sector and BPB Structure[Fat32]-> BPB_Reserved [Offset=52, Size=12]
Fat32 - Boot Sector and BPB Structure[Fat32]-> BPB_FSVer [Offset=42, Size=2]
This field is only defined for FAT32 media and does not exist on FAT12 and FAT16 media. High byte is major revision number. Low byte is minor revision number. This is the version number of the FAT32 volume. This supports the ability to extend the FAT32 media type in the future without worrying about old FAT32 drivers mounting the volume. This document defines the version to 0:0. If this field is non-zero, back-level Windows versions will not mount the volume. NOTE: Disk utilities should respect this field and not operate on volumes with a higher major or minor version number than that for which they were designed. FAT32 file system drivers must check this field and not mount the volume if it does not contain a version number that was defined at the time the driver was written.