Format of BIOS Parameter Block:
Offset	Size	Description	)
 00h	WORD	number of bytes per sector
 02h	BYTE	number of sectors per cluster
 03h	WORD	number of reserved sectors at start of disk
 05h	BYTE	number of FATs
 06h	WORD	number of entries in root directory
 08h	WORD	total number of sectors
		for DOS 4.0+, set to zero if partition >32M, then set DWORD at
		  15h to actual number of sectors
 0Ah	BYTE	media ID byte (see #01356)
 0Bh	WORD	number of sectors per FAT
---DOS 2.13---
 0Dh	WORD	number of sectors per track
 0Fh	WORD	number of heads
 11h	WORD	number of hidden sectors
---DOS 3.0+ ---
 0Dh	WORD	number of sectors per track
 0Fh	WORD	number of heads
 11h	DWORD	number of hidden sectors
 15h 11 BYTEs	reserved
---DOS 4.0+ ---
 15h	DWORD	total number of sectors if word at 08h contains zero
 19h  6 BYTEs	???
 1Fh	WORD	number of cylinders
 21h	BYTE	device type
 22h	WORD	device attributes (removable or not, etc)
---DR DOS 5+ ---
 15h	DWORD	total number of sectors if word at 08h contains zero
 19h  6 BYTEs	reserved
---European MS-DOS 4.00---
 15h	DWORD	total number of sectors if word at 08h contains zero
		(however, this DOS does not actually implement >32M partitions)
SeeAlso: #01395,#01664