Format of xDISK data buffer:
Offset	Size	Description	)
 00h	DWORD	pointer to ASCIZ driver signature "xDISK unit: X"
 04h	BYTE	flag: 01h if disk linked to DOS, 00h if unlinked
 05h	BYTE	flag: 01h if write protected, 00h if not
 06h	BYTE	flag: 01h if root directory full, 00h if not
 07h	BYTE	flag: 01h if free space uncompacted, 00h if compacted
 08h	BYTE	resizing state: 00h not resizable, 01h resized, 80h resizable
 09h	BYTE	flag: 01h inelastic resizable disk, 00h elastic
 0Ah  2 BYTEs	reserved
 0Ch	BYTE	flag: 01h collapsed disk, 00h not collapsed
 0Dh	BYTE	flag: 01h using all EMS, 00h some EMS free
 0Eh	BYTE	flag: 01h password enabled, 00h disabled
 0Fh	BYTE	flag: 01h password audio feedback, 00h no feedback
 10h	BYTE	flag: 01h password video feedback, 00h no feedback
 11h	BYTE	flag: 01h confirm changes, 00h no confirmation
 12h	BYTE	flag: 01h terse display, 00h verbose display
 13h	BYTE	flag: 01h click speaker on disk access, 00h no click
 14h	BYTE	flag: 01h flash icon on disk access, 00h no icon flash
 15h	BYTE	FAT entry size: 00h 12-bit, FFh 16-bit
 16h	WORD	count of open files in RAM disk
 18h	BYTE	unused