Extended Boot Sector
| Offset | Size | Description | Comments |
|---|---|---|---|
| 0 (0x00) | 2BytesPerSectorShift - 4 | ExtendedBootCode | |
| 2BytesPerSectorShift - 4 | 4 | ExtendedBootSignature | 0xAA550000 |
Whole sector is used for boot code except last 4 bytes used for signature in each sector. If Extended Boot Sector is not used, it should be filled with 0x00. Extended signature must be preserved.