Perhaps this will help you... (The MBR contains this table and so does the 
extended partition boot record)
 HelpPC 2.10           Quick Reference Utility     Copyright 1991 David 
Jurgens
             Disk Partition Table (Fixed disk boot record)
       Offset       Represents:  (see format below)
        01BE        Partition 1 data table  (16 bytes)
        01CE        Partition 2 data table  (16 bytes)
        01DE        Partition 3 data table  (16 bytes)
        01EE        Partition 4 data table  (16 bytes)
        01FE        Signature  (hex 55 AA, 2 bytes)
        Offset from beginning of partition data shown above:
      Offset Size               Description
        00   byte   boot indicator
        01   byte   beginning sector head number
        02   byte   beginning sector (2 high bits of cylinder #)
        03   byte   beginning cylinder# (low order bits of cylinder #)
        04   byte   system indicator
        05   byte   ending sector head number
        06   byte   ending sector (2 high bits of cylinder #)
        07   byte   ending cylinder# (low order bits of cylinder #)
        08   dword  number of sectors preceding the partition
        0B   dword  number of sectors in the partition
        Boot indicator (BYTE)
        00  - non-bootable partition
        80  - bootable partition (one partition only)
        System Indicator (BYTE)
        00 - unknown operating system
        01 - DOS with 12 bit FAT, 16 bit sector number
        02 - XENIX
        04 - DOS with 16 bit FAT, 16 bit sector number
        05 - DOS Extended partition (DOS 3.3+)
        06 - DOS 4.0 (Compaq 3.31), 32 bit sector number
        51 - Ontrack extended partition
        64 - Novell
        75 - PCIX
        DB - CP/M
        FF - BBT
        Signature
        Hex 55AA marks the end of valid boot sector.     This is also
        required in each of the partition boot records.
        Sector/Cylinder
        2 bytes are combined to a word similar to INT 13:
        I7I6I5I4I3I2I1I0I 1st byte  (sector)
         I I `-+-+-+-+-+-- Sector offset within cylinder
         `-+------------- High order bits of cylinder #
        I7I6I5I4I3I2I1I0I 2nd byte  (cylinder)
         `-+-+-+-+-+-+----- Low order bits of cylinder #
        - all partitions begin on sector 1 head 0, except the first
          partition which follows the disk's master boot record and begins
          in sector 2
        - some of this information may vary with some variants of DOS 3.2
          and DOS 3.3 that use their own sectoring scheme for large disks
        - see  INT 21,32  Disk Partition Table
 -------------
nihil
--- BBBS/NT v3.33 How
---------------