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Table 2601

Format of DOS 3.30 drive data table:
Offset	Size	Description	)
 00h	DWORD	pointer to next table (offset FFFFh if last table)
 04h	BYTE	physical unit number (for INT 13)
 05h	BYTE	logical drive number (0=A:)
 06h 19 BYTEs	BIOS Parameter Block (see also INT 21/AH=53h)
		Offset	Size	Description
		 00h	WORD	bytes per sector
		 02h	BYTE	sectors per cluster, FFh if unknown
		 03h	WORD	number of reserved sectors
		 05h	BYTE	number of FATs
		 06h	WORD	number of root dir entries
		 08h	WORD	total sectors
		 0Ah	BYTE	media descriptor, 00h if unknown
		 0Bh	WORD	sectors per FAT
		 0Dh	WORD	sectors per track
		 0Fh	WORD	number of heads
		 11h	WORD	number of hidden sectors
 19h	BYTE	flags
		bit 6: 16-bit FAT instead of 12-bit FAT
 1Ah	WORD	number of DEVICE OPEN calls without corresponding DEVICE CLOSE
 1Ch 11 BYTEs	volume label or "NO NAME    " if none (always "NO NAME" for
		  fixed media)
 27h	BYTE	terminating null for volume label???
 28h	BYTE	device type (see #01561 at INT 21/AX=440Dh"DOS 3.2+")
 29h	WORD	bit flags describing drive (see #02604)
 2Bh	WORD	number of cylinders
 2Dh 19 BYTEs	BIOS Parameter Block for highest capacity supported
 40h  3 BYTEs	???
 43h  9 BYTEs	filesystem type???, default = "NO NAME	"
		(apparently only MS-DOS 3.30 fixed media, nulls for removable
		  media and PC-DOS 3.30)
 4Ch	BYTE	least-significant byte of last-accessed cylinder number
---removable media---
 4Dh	DWORD	time of last access in clock ticks (FFFFFFFFh if never)
---fixed media---
 4Dh	WORD	partition (FFFFh = primary, 0001h = extended)
 4Fh	WORD	absolute cylinder number of partition's start on physical
		  drive (always FFFFh if primary partition)
SeeAlso: #02602,#02603

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