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Table 1560

Format of parameter block for functions 40h, 60h:
Offset	Size	Description	)
 00h	BYTE	special functions
		bit 0 set if function to use current BPB, clear if Device
			  BIOS Parameter Block field contains new default BPB
		bit 1 set if function to use track layout fields only
			must be clear if CL=60h
		bit 2 set if all sectors in track same size (should be set)
		bits 3-7 reserved (MS-DOS, Novell DOS 7)
		bit 5: skip head settling time (WinDOS 2.11)
		bit 6: format access flag (WinDOS 2.11)
 01h	BYTE	device type (see #01561)
 02h	WORD	device attributes
		bit 0 set if nonremovable medium
		bit 1 set if door lock ("changeline") supported
		bits 2-15 reserved
 04h	WORD	number of cylinders
 06h	BYTE	media type
		for 1.2M drive
		    00h 1.2M disk (default)
		    01h 320K/360K disk
		F8h for DUBLDISK.SYS v2.6 expanded drives
		always 00h for other drive types
 07h 31 BYTEs	device BPB (see #01663 at AH=53h), bytes after BPB offset 1Eh
		  omitted; final six bytes only transferred on function 40h
		  with BYTE 00h bit 0 set for MS-DOS 5.0
---function 40h only---
 26h	WORD	number of sectors per track (start of track layout field)
		(maximum 63)
 28h  N word pairs: number,size of each sector in track
---category code 48h (FAT32), function 40h---
 07h 53 BYTEs	extended BPB (see #01664)
 3Ch 32 BYTEs	reserved
 5Ch	WORD	number of track table entries
 5Eh 2N WORDs	sector table (word pairs: number/size of each sector in track)
---category code 48h (FAT32), function 60h---
 07h 53 BYTEs	extended BPB (see #01664)
 3Ch 32 BYTEs	reserved


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  Copyright 2000   by Ralf Brown     Updated Jul 2000