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

Models: T13/2132-D

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