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BIOS Enhanced Disk Drive Specification BIOS
Enhanced Disk Drive Specification
Version 1.1
May 9, 1995
Technical Editor:
Curtis E. Stevens
Phoenix Technologies
2575 M
c
Cabe Way
Irvine, Ca. 92714
Phone: (714) 440-8000
Fax: (714) 440-8300
Curtis_Stevens@BanNet.PTLTD.COM
Phoenix Technologies Ltd.
THIS SPECIFICATION IS MADE AVAILABLE WITHOUT CHARGE FOR USE IN DEVELOPING
COMPUTER SYSTEMS AND DISK DRIVES. PHOENIX MAKES NO REPRESENTATION OR
WARRANTY REGARDING THIS SPECIFICATION OR ANY ITEM DEVELOPED BASED ON THIS
SPECIFICATION, AND PHOENIX DISCLAIMS ALL EXPRESS AND IMPLIED WARRANTIES,
INCLUDING BUT NOT LIMITED TO THE IMPLIED WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND FREEDOM FROM INFRINGEMENT. WITHOUT
LIMITING THE GENERALITY OF THE FOREGOING, PHOENIX MAKES NO WARRANTY OF
ANY KIND THAT ANY ITEM DEVELOPED BASED ON THIS SPECIFICATION WILL NOT
INFRINGE ANY COPYRIGHT, PATENT, TRADE SECRET OR OTHER INTELLECTUAL
PROPERTY RIGHT OF ANY PERSON OR ENTITY IN ANY COUNTRY. USE OF THIS
SPECIFICATION FOR ANY PURPOSE IS AT THE RISK OF THE PERSON OR ENTITY USING IT.
®
® Enhanced Disk Drive Specification
Version 1.1
Phoenix Technologies Ltd
Version 1.1 Copyright
©
1995 Phoenix Technologies Ltd. All Rights Reserved. Enhanced Disk Drive Specification
PRELIMINARY
Version 1.1
Phoenix Technologies Ltd
Page iii
Revision History
Rev
Date
Description
1.0
January 25, 1994
Initial Release
1.1
January 25, 1995
Added the following:

Description of the 528 MB limitation

Description of compatibility issues caused by translation

Description of Int 13h Extensions as implemented by Phoenix

Description of the Translated Fixed Disk Parameter Table.

Support for ATAPI devices

Support for translation reporting
Companies Supporting this Specification
Phoenix Technologies
2575 McCabe Way
Irvine, Ca. 92714
Phone: (714) 440-8000
Fax: (714) 440-8300
Enhanced Disk Drive Specification
Version 1.1
Phoenix Technologies Ltd
Page i
Table of Contents
1. OVERVIEW.........................................................................................................1
1.1 Scope .......................................................................................................................................................... 1
1.2 Introduction............................................................................................................................................... 1
1.3 Definition of Terms ................................................................................................................................... 1
1.3.1 Enhanced BIOS ................................................................................................................................... 1
1.3.2 Enhanced IDE Device.......................................................................................................................... 1
1.3.3 Enhanced IDE Channel........................................................................................................................ 1
1.3.4 Conventional vs Enhanced .................................................................................................................. 1
2. FIXED DISK PARAMETER TABLES (FDPT) .....................................................2
2.1 Fixed Disk Parameter Table (FDPT) Extensions .................................................................................... 2
2.2 The 528-Megabyte Barrier ....................................................................................................................... 2
2.3 Fixed Disk Parameter Table (FDPT) Definitions .................................................................................... 6
2.3.1 Physical Values ................................................................................................................................... 6
2.3.2 Logical Values..................................................................................................................................... 6
2.3.3 Obsolete Fields .................................................................................................................................... 6
2.4 Fixed Disk Parameter Table (FDPT) Extension ..................................................................................... 6
2.4.1 Bytes 0-1 - I/O Port Base..................................................................................................................... 6
2.4.2 Bytes 2-3 - Control Port Base.............................................................................................................. 6
2.4.3 Byte 4 - Head Prefix ............................................................................................................................ 6
2.4.4 Byte 5 - Internal Use Only................................................................................................................... 6
2.4.5 Byte 6 - IRQ ........................................................................................................................................ 6
2.4.6 Byte 7 - Sector Count .......................................................................................................................... 6
2.4.7 Byte 8 - DMA Channel/DMA Type .................................................................................................... 6
2.4.8 Byte 9 - PIO Type................................................................................................................................ 6
2.4.9 Byte 10-11 - Hardware Specific Option Flags ..................................................................................... 7
2.4.9.1 Bit 0 - Fast PIO............................................................................................................................. 7
2.4.9.2 Bit 1 - Fast DMA.......................................................................................................................... 7
2.4.9.3 Bit 2 - Block PIO.......................................................................................................................... 7
2.4.9.4 Bit 3 - CHS Translation ................................................................................................................ 7
2.4.9.5 Bit 4 - LBA Translation................................................................................................................ 7
2.4.9.6 Bit 5 - Removable Media ............................................................................................................. 7
2.4.9.7 Bit 6 - ATAPI Device ................................................................................................................... 7
2.4.9.8 Bit 7 - 32-bit Transfer Mode......................................................................................................... 7
2.4.9.9 Bit 8 - ATAPI Device uses Interrupt DRQ ................................................................................... 7
2.4.9.10 Bits 9-10 - Translation Type....................................................................................................... 7
2.4.10 Byte 14 - Extension Revision ............................................................................................................ 7
2.4.11 Byte 15 - Checksum .......................................................................................................................... 8
3. BIOS EXTENSIONS ...........................................................................................8
3.1 Calling Conventions .................................................................................................................................. 8 Enhanced Disk Drive Specification
Version 1.1
Page ii
Phoenix Technologies Ltd
3.1.1 Data Structure.......................................................................................................................................8
3.1.2 Extended Int 13h Conventions ...........................................................................................................10
3.1.3 Int 13h Interface Subsets ....................................................................................................................10
3.1.3.1 Fixed Disk Access.......................................................................................................................10
3.1.3.2 Drive Locking and Ejecting ........................................................................................................10
3.1.3.3 Enhanced Disk Drive (EDD) Support .........................................................................................10
3.2 Int 13h Extensions ...................................................................................................................................10
3.2.1 Check Extensions Present ..................................................................................................................10
3.2.2 Extended Read ...................................................................................................................................11
3.2.3 Extended Write...................................................................................................................................11
3.2.4 Verify Sectors.....................................................................................................................