The format of partition table entry of any Partition in MBR has been given in the next table. Every Partition Entry of any MBR may be broken into the following bytes with their specific meanings:
Offset |
Meaning |
Size |
Description |
00H |
Boot Type Indicator Byte |
1 Byte |
If Byte is 00H, the Partition is Inactive and if Byte is 80H, The Partition is Active (or Bootable) |
01H |
Head Number of Beginning of the Partition |
1 Byte |
Starting Head number of the Partition in Hexadecimal System |
02H |
Sector and Cylinder Number of Beginning of the Partition |
2 Bytes |
6 Bits of First Byte make Starting Sector Number and Combination of remaining 2 Bits (as Two Most Significant Bits) plus 8 Bits of another Byte (Rest 8 least Significant Bits of the 10-Bit Number ) make the Starting Cylinder Number of the Partition |
04H |
File System indicator Byte |
1 Byte |
File System Indicator Byte in Hexadecimal system |
05H |
Head Number of End of the Partition |
1 Byte |
Ending Head Number of the Partition in Hexadecimal System |
06H |
Sector and Cylinder Number of End of the Partition |
2 Bytes |
6 Bits of First Byte make Ending Sector Number and Combination of remaining 2 Bits (as Two Most Significant Bits) plus 8 Bits of another Byte (Rest 8 least Significant Bits of the 10-Bit Number ) make the Ending Cylinder Number of the Partition |
08H |
Absolute Sector number of Beginning of the Partition |
4 Bytes |
Number of Sectors Between the MBR and the First Sector in the Partition |
0CH |
Absolute Sector number of End of the Partition |
4 Bytes |
Number of Sectors in the Partition |
Total = 16 Bytes |
The program to read all four partition entries from partition table of MBR has been given next. The program displays all the parameters of partition information, written in partition table of MBR.
