INT 13 - SWBIOS - INSTALLATION CHECK                                            
	AH = F9h
	DL = drive number (80h,81h)
Return: CF clear
	    DX = configuration word
		bit 15 set if other SWBIOS extensions available
	CF set on error
Program: SWBIOS is a TSR(Terminate and Stay Resident) A program which remains in memory after terminating in order to provide services to other programs or the user.  The name comes from the name of the DOS function call used to remain in memory after termination. by Ontrack Computer Systems
	XBIOS is a driver in some versions of Disk Manager that is
	  loaded from the disk MBR, replacing the ROM(Read-Only Memory) A memory for program storage which may not be changed by the program as it runs. BIOS(Basic Input/Output System) A set of standardized calls giving low-level access to the hardware.  The BIOS is the lowest software layer above the actual hardware and serves to insulate programs (and operating systems) which use it from the details of accessing the hardware directly. disk support
	  eg adding LBA mode support, and read/write multiple.
Note:	Disk Manager also supports these calls
SeeAlso: AH=EEh,AX=E000h"XBIOS",AH=FFh"EZ-Drive"
Index:	Disk Manager