Boot Methods, Emulation Process | Western Digital T13/2132-D

June 23, 2010

T13/2132-D Revision 3

Figure 6 illustrates a multi-session CD or DVD with several boot images. This type of CD or DVD may be used in a recovery environment that has several different system types. The Initial/Default entry could be a program that determines the system type and then chooses the appropriate boot image.

	Boot Image 2
	System Area
	(Unused)
Sector 16	Primary Volume Descriptor
Sector 17	Boot Record Volume Descriptor
	...
	...
	...
	...
	...
	Set Terminator Volume Descriptor
	Area 1
	(Could be files)
	Boot Catalog
	Validation Entry
	Initial/Default Entry
	Section Header
	Boot Image 1
	Boot Image 2
	Boot Image 3
	Boot Image 3
	Area 2
	Boot Image 1
	Initial/Default Disk Image

Figure 6 — Boot CD or DVD with multiple boot images

7.2 Boot Methods

7.2.1 Overview

Bootable CD's and DVD's shall have bootable images that follow one of the following media types.

a)No Emulation Boot

b)1.22MB Floppy

c)1.44MB Floppy

d)2.88MB Floppy

e)Hard Disk

Each of these formats has different requirements for booting. INT 13h FNs 00h through 3Fh shall operate in the emulated sector size of 512 bytes. Addressing for these functions shall be in 512 byte increments relative to the start of the emulated image. For example, if a boot image starts at sector 100 on a CD, INT 13h sectors zero through three would reside at sector 100 offset 0, 512, 1024, and 1536 bytes respectively on the CD.

7.2.2 Emulation Process

CD's and DVD's use a sector size that is 2KB. Floppy disks and hard drives commonly use a sector size of 512 bytes. In an emulated bootable CD or DVD environment, the system BIOS shall assign a device number to the bootable image. INT 13h FNs 00h through 3Fh shall continue to operate with a 512-byte sector size. The data

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

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Image 33

Western Digital T13/2132-D manual Boot Methods, Emulation Process

Contents

Revision June 23 Information technology Enhanced Disk Drive 4 EDD-4 Points of Contact T13/2132-D Revision 3June 23Working Draft Enhanced Disk Drive 4 EDD-4 June 23 T13/2132-D Revision Draft T13/2132-D Revision June 23 American National Standard New Capabilities added to EDD-4 Document Status Contents Working Draft Enhanced Disk Drive 4 EDD-4 Vii Viii Working Draft Enhanced Disk Drive 4 EDD-4 Output Parameters Tables Figures Introduction Foreword Xii Working Draft Enhanced Disk Drive 4 EDD-4 Scope BSR IncitsAmerican National Standard for Information Technology ATA8-APT ATA8-AST Normative references General Approved referencesApproved Ansi References Name References under development Other referencesReferences Under Development Name Project Number June 23 T13/2132-D Revision Master Boot Record MBR The first LBA on a disk Symbols and abbreviationsConventions Abbreviation Meaning Lists Lists overview PrecedenceUnordered lists Ordered lists Numbering T13/2132-D Revision June 23 Keywords Interrupt Services and Functions Register and CF ContentsNumbering conventions French English This standard Bit conventions Word at offset n ByteDWord at word offset n QWord at word offset n ATA firmware revision example ATA string byte swapping Word Byte Character in stringWord Byte Value Overview Conventional Register Definitions 8GB INT 13h Functions Conventional FunctionsRegister Description Bit Description Conventional Function Definitions Function a Description Data Structure 8GB INT 13h Functions OverviewExtended Function Definitions Function Description T13/2132-D Revision June 23 Device Address Packet Offset Fixed Disk Access Function Code Fixed Disk Access SubsetRemovable Media INT 13h Interface Subsets Locking and Ejecting Function Code Enhanced Disk Drive EDD Support SubsetEDD Support Function Code ISO 9660 CD Layout Working Draft Enhanced Disk Drive 4 EDD-4 CD/DVD Boot Overview System Area Unused Emulation Process Boot Methods Floppy Boot No Emulation BootHard Drive Boot Floppy Geometries Type Cylinders Heads Sectors Boot Volume Descriptor BVD Boot Volume DescriptorCD/DVD Format Offset Type Description T13/2132-D Revision June 23 Validation Entry Section Header June 23 T13/2132-D Revision Initial/Default Entry 00h Byte Header ID Type Description June 23 T13/2132-D Revision Section Entry T13/2132-D Revision June 23 Section Entry Extension INT 13h Function Definitions Overview Reset Disk Subsystem FN 00h Get Status of Last Operation FN 01h Read Sectors into Memory FN 02h Write Sectors From Memory FN 03h Verify Sectors FN 04h Get Drive Parameters FN 08h Read Buffer FN 0Eh Write Buffer FN 0Fh Value Description Get Disk Type FN 15h Set Media Type FN 18h Park Heads FN 19h Identify Device Information FN 25h Interface Support Bit Map Description Check Extensions Present FN 41h Extended Read FN 42h Extended Write FN 43h Verify Sectors FN 44h Lock/Unlock Media FN 45h Eject Removable Media FN 46h Result Buffer Get Device Parameters FN 48h Ascii Interface Path Definitions part 1 Host Bus Type Offset T13/2132-D Revision June 23 Interface Path Device Path Definition 00h ATA Device 01h 02h..FFh Reserved Byte Word DWord QWord Byte Port number Device parameter table extension Offset 7 READ/WRITE Multiple command block count Offset 5 Bios use only Bios use only Offset 6 IRQ numberOffset 0-1 I/O port base Offset 2-3 control port base Bit 7 32-bit transfer mode Offset 10-11 Bios selected hardware specific option flagsBit 8 Atapi device uses command packet interrupt Offset 9 PIO type June 23 T13/2132-D Revision Bits 9-10 translation type Bit 13h 48-bit LBA addressing enabledTranslation Type Bits Description Bit 11 Ultra DMA Get Extended Media Change Status FN 49h Initiate Disk Emulation FN 4Ah Value Emulation Working Draft Enhanced Disk Drive 4 EDD-4 Terminate Disk Emulation FN 4Bh Initiate Disk Emulation & Boot FN 4Ch CD Command Packet Return Boot Catalog FN 4Dh Hardware Configuration Sub-Functions Set Hardware Configuration FN 4Eh Formatted Command Packet Offset Type Description Send Packet Command FN 50h Formatted Protocol Specific Data T13/2132-D Revision June 23 Output Parameters Security Protocol Commands FN 51h INT 15h Removable Media Eject Hybrid MBR boot Hybrid MBR boot overview GPT support for hybrid MBR boot codeAnnex a Hybrid MBR boot code EAX Hybrid MBR boot code endeavor procedure Hybrid VBR boot code