INT 21 - DOS 1+ - GET DRIVE PARAMETER BLOCK FOR DEFAULT DRIVE

	AH = 1Fh
Return: AL = status
	    00h successful
		DS:BX -> Drive Parameter Block (DPB) (see #01357 for DOS 1.x,
			AH=32h for DOS 2+)
	    FFh invalid drive
Note:	this call was undocumented prior to the release of DOS 5.0; however,
	  only the DOS 4.0+ version of the DPB has been documented
SeeAlso: AH=32h,AX=7302h