Western Digital T13/2132-D manual Bit Description, Value Emulation

T13/2132-D Revision 3				June 23, 2010
				Table 27 — CD Specification Packet
Offset	Type			Description
0	Byte	13h (e.g., Packet size in bytes)
1	Byte	Boot Media Type
		Bit	Description
		7	Emulated image requirements
			Value	Description
			0b	Emulated image is not driver dependent
			1b	Emulated image contains SCSI drivers for CD/DVD-ROM, bytes 8 and 9 refer
				to a SCSI interface
		6	Emulated image requirements
			Value	Description
			0b	Emulated image is not driver dependent
			1b	Emulated image contains ATAPI drivers for CD/DVD-ROM, bytes 8 and 9 refer
				to an ATAPI interface
		5:4	Reserved
		3:0	Type of image to be booted
			Value	Emulation
			0	No Emulation
			1	1.2MB Diskette
			2	1.44MB Diskette
			3	2.88MB Diskette
			4	Hard Disk
			5-Fh	Reserved
2	Byte	INT 13h device number. This shall be the INT 13h number of the device which shall be started
		or terminated. This value shall be zero for a floppy image, 80h for a bootable hard disk, and
		81h through FFh for a non-bootable or no emulation device.
3	Byte	Controller Index. This shall be the controller number of the to which the CD/DVD-ROM drive is
		attached. If there are several controllers in a system, their number is system dependent.

4-7 DWord Logical Block Address of the disk image to be emulated. This shall be the absolute sector address of the image on the CD or DVD media.

8-9	Word	Device Number. SCSI controllers shall use byte 8 as the Logical Unit Number (LUN) and byte
		9 as the Physical Unit Number (PUN) of the CD or DVD drive. ATA/ATAPI controllers shall use
		bit 0 of byte 8 to indicate device 0 or device 1.
10-11	Word	User Buffer Segment. If this field is non-zero, the system may use a supplied buffer for
		caching CD/DVD reads. This buffer shall be at least 3k in size. The buffer begins at
		segment:0
12-13	Word	Load Segment. This field is only used for booting (INT 13h FN 4Ch). If the value is zero, the
		system shall use 7C0h as the load address and start address for booting. if the value is
		non-zero, the system shall load the boot image at segment:0 and initiate the boot process by
		jumping to segment:0

60 Working Draft Enhanced Disk Drive - 4 (EDD-4)