Function  69h	Get or Set BIOS Parameter Block Extention      (DOS 4.0)
entry	AH	69h
	AL	00	Get BPBE
			DS:DX	Buffer Address
			return	copy of BPBE in Buffer.
		01	Write buffer to BPBE
			DS:DX	Buffer Address
			return	Buffer contents written to disk as BPBE.
	BL	Drive Number
return	CF	set if error
		AX	error code
note 1) Ref: PC Magazine Vol 11 No 13 Pg 495
     2) The BIOS Parameter Block Extension is an addition to the BIOS Parameter
	Block added in DOS 4.0 which contains an Information Level(?), Diskett
	Serial Number, a copy of the volumn lable, and the name of the file
	system used.
    Offset Length  Name
	-- ------- ---------------------------------
	00 WORD    Information Level(?)
	02 LONGINT Serial Number
	   11 BYTE Volumn Lable (?)
	   8 BYTE  File System ('FAT12' or 'FAT16')