INT 13,18 - Set Media Type for Format (BIOS date specific)

	AH = 18h
	CH = lower 8 bits of number of tracks  (0-1023 dec., see below)
	CL = sectors per track (1-17 dec., see below)
	DL = drive number (0=A:, 1=2nd floppy, 80h=drive 0, 81h=drive 1)


	on return:
	ES:DI = pointer to 11-byte Disk Base Table (DBT)
	AH = 00h if requested combination supported
	   = 01h if function not available
	   = 0Ch if not supported or drive type unknown
	   = 80h if there is no media in the drive
	CF = 0 if successful
	   = 1 if error


	- valid only for XT BIOS dated after 1/10/86, AT after 11/15/86,
	  XT 286 and the PS/2 line
	- only disk number is checked for validity
	- track number is a 10 bit value taken from the 2 high order
	  bits of CL and the 8 bits in CH (low order 8 bits of track):

	  |F|E|D|C|B|A|9|8|7|6|5|4|3|2|1|0|  CX
	   | | | | | | | | | | `--------------	sectors per track count
	   | | | | | | | | `--------------  high order 2 bits track/cyl count
	   `--------------------------	low order 8 bits of track/cyl count

	- see	INT 13,STATUS