Western Digital T13/2132-D manual No Emulation Boot, Floppy Boot, Hard Drive Boot

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T13/2132-D Revision 3

June 23, 2010

that is on the floppy or hard disk drive (HDD) shall be packed four sectors of data to each sector on the CD or DVD. This packing shall be performed in a linear fashion so that floppy or HDD sectors zero through three become the first sector in the image on the CD or DVD. Packing shall continue so that floppy or HDD sectors four through seven are the second sector on the CD or DVD, floppy or HDD sectors 8 through 11 are the third sector in the image on the CD or DVD. This process is repeated until all the data is on the CD or DVD. INT 13h FNs 00h through 3Fh shall then unpack the data based on the calling parameters. This method allows software on the CD or DVD to use the system BIOS without taking into account the CD or DVD hardware or sector size. This method also allows a floppy or HDD image to be tested and debugged using a normal floppy or HDD. Once the image on the media is booting and operating properly, the image may then be transferred to the CD or DVD with a high degree of confidence that it will function properly.

INT 13h Functions 41h through 49h access the CD or DVD using non-emulated sector LBA's in the native sector size of the CD or DVD. INT 13h FN 48h shall return the total number of 2KB sectors on the CD or DVD and shall set the flag that indicates the geometry is invalid. This capability allows software to use generic ISO-9660 or other file system drivers without requiring a CD or DVD hardware specific driver. This capability allows the software to boot and run, provided the software uses INT 13h functions exclusively, regardless of the interface bus type. This means that a CD or DVD boot image may be constructed that works the same on ATAPI, Fibre Channel, SCSI, USB, 1394, and other buses. If the system is EDD-3 compliant, the Initial/Default Image may make an INT 13h FN 48h call, determine the interface bus type, and then boot an image with native CD or DVD drivers to perform the requested operation.

7.2.3 No Emulation Boot

If an image is marked as No Emulation Boot, the system BIOS shall load the specified number of sectors and jump to the specified segment number to start the boot program executing. Since this is a no emulation boot, the system BIOS shall not provide access to the media through INT 13h FNs 00h through 3Fh. The system BIOS shall assign the CD-ROM drive a device number. A common industry number is A0h. This is outside the range of normal BIOS hard drive numbers (above 9Ah), but still within INT 13h range limitation.

7.2.4 Floppy Boot

When the system attempts to boot a Floppy based image, it shall assign device number 0 to the image. If there are one or more standard floppy drives present in the system, they shall be sequentially numbered by the BIOS starting from one and increasing.

EDD-4 supports 3 different floppy formats: 1.2MB, 1.44MB, and 2.88MB. All of these formats can be created on a floppy disk first, tested, and then transferred to the target CD or DVD. Table 14 describes the geometries INT 13h FN 8h shall return for each floppy type.

Table 14 — Floppy Geometries

Type

Cylinders

Heads

Sectors

1.2MB

80

2

15

 

 

 

 

1.44MB

80

2

18

 

 

 

 

2.88MB

80

2

36

 

 

 

 

The total capacity of a CD is more than 600MB. Many floppy images may be embedded on one CD or DVD, since floppy images shall be 2.88MB or less. One reason for making a bootable floppy image is to boot the system, load a CD or DVD specific device driver and then provide access to all the media. This capability allows a simple OS, such as DOS, to be used for accessing a self-contained CD. One application for this capability is system recovery or system restore.

7.2.5 Hard Drive Boot

When the system attempts to boot a Hard Disk Drive (HDD) based image, it shall assign device number 80h to the image. If there are one or more standard disk devices present in the system, they shall be numbered sequentially starting at 81h and increasing.

The geometry returned by INT 13h FN 08h is based on the partition table embedded in the first sector of the HDD image. The partition type of HDD images shall include cylinder-head-sector (CHS) addresses. Any partition type

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

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Contents Information technology Enhanced Disk Drive 4 EDD-4 Revision June 23T13/2132-D Revision 3June 23 Points of ContactWorking Draft Enhanced Disk Drive 4 EDD-4 Draft June 23 T13/2132-D RevisionAmerican National Standard T13/2132-D Revision June 23Document Status New Capabilities added to EDD-4Contents Working Draft Enhanced Disk Drive 4 EDD-4 Vii Viii Working Draft Enhanced Disk Drive 4 EDD-4 Tables Output ParametersFigures Foreword IntroductionXii Working Draft Enhanced Disk Drive 4 EDD-4 BSR Incits ScopeAmerican National Standard for Information Technology ATA8-APT ATA8-AST Approved references Normative references GeneralApproved Ansi References Name Other references References under developmentReferences Under Development Name Project Number June 23 T13/2132-D Revision Conventions Symbols and abbreviationsMaster Boot Record MBR The first LBA on a disk Abbreviation MeaningUnordered lists PrecedenceLists Lists overview Ordered listsT13/2132-D Revision June 23 Keywords NumberingNumbering conventions French English This standard Register and CF ContentsInterrupt Services and Functions Bit conventionsDWord at word offset n ByteWord at offset n QWord at word offset nWord ATA string byte swapping Word Byte Character in stringATA firmware revision example Byte ValueOverview Register Description 8GB INT 13h Functions Conventional FunctionsConventional Register Definitions Bit DescriptionConventional Function Definitions Function a Description Extended Function Definitions 8GB INT 13h Functions OverviewData Structure Function DescriptionT13/2132-D Revision June 23 Device Address Packet Offset Removable Media Fixed Disk Access SubsetFixed Disk Access Function Code INT 13h Interface SubsetsEnhanced Disk Drive EDD Support Subset Locking and Ejecting Function CodeEDD Support Function Code CD/DVD Boot Overview ISO 9660 CD Layout Working Draft Enhanced Disk Drive 4 EDD-4System Area Unused Boot Methods Emulation ProcessHard Drive Boot No Emulation BootFloppy Boot Floppy Geometries Type Cylinders Heads SectorsBoot Volume Descriptor Boot Volume Descriptor BVDCD/DVD Format T13/2132-D Revision June 23 Validation Entry Offset Type DescriptionJune 23 T13/2132-D Revision Initial/Default Entry Section Header00h Byte Header ID June 23 T13/2132-D Revision Section Entry Type DescriptionT13/2132-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 Get Disk Type FN 15h Value DescriptionSet Media Type FN 18h Park Heads FN 19h Identify Device Information FN 25h Check Extensions Present FN 41h Interface Support Bit Map DescriptionExtended Read FN 42h Extended Write FN 43h Verify Sectors FN 44h Lock/Unlock Media FN 45h Eject Removable Media FN 46h Get Device Parameters FN 48h Result BufferAscii T13/2132-D Revision June 23 Interface Path Interface Path Definitions part 1 Host Bus Type OffsetDefinition Device Path00h ATA Device 01h 02h..FFh Reserved Byte Word DWord QWord Byte Port number Device parameter table extension Offset 0-1 I/O port base Offset 5 Bios use only Bios use only Offset 6 IRQ numberOffset 7 READ/WRITE Multiple command block count Offset 2-3 control port baseBit 8 Atapi device uses command packet interrupt Offset 10-11 Bios selected hardware specific option flagsBit 7 32-bit transfer mode Offset 9 PIO typeTranslation Type Bits Description Bit 13h 48-bit LBA addressing enabledJune 23 T13/2132-D Revision Bits 9-10 translation type Bit 11 Ultra DMAGet 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 Return Boot Catalog FN 4Dh CD Command PacketSet Hardware Configuration FN 4Eh Hardware Configuration Sub-FunctionsSend Packet Command FN 50h Formatted Command Packet Offset Type DescriptionFormatted Protocol Specific Data T13/2132-D Revision June 23 Output Parameters Security Protocol Commands FN 51h INT 15h Removable Media Eject GPT support for hybrid MBR boot code Hybrid MBR boot Hybrid MBR boot overviewAnnex a Hybrid MBR boot code Hybrid MBR boot code endeavor procedure EAXHybrid VBR boot code
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