  FIXED IDE HARD DRIVE AND REMOVABLE MEDIA SUPPORT

  June 27, 2005

  OS/2 Device Driver Development
  IBM Solution Technologies
  Austin, TX

  (c) Copyright International Business Machines Corporation, 2001, 2005.
  All rights Reserved.

  CONTENTS
  ________

    Prerequisite Support

  1  Introduction

  2  Installation
  2.1  Updating the Installation Diskettes
  2.2  Updating a Previously Installed Warp System
  2.3  Recommended Parameters for IBM1S506.ADD
  2.4  Recommended Parameters for IBMATAPI.FLT and IBMIDECD.FLT
  2.5  Recommended Parameters for IBM1FLOPPY.ADD

  3  Large Hard Drive Considerations
  3.1  System Hang or Hard Drive Hesitation
  3.2  Cannot Mark a Partition Installable
  3.3  IPE on Boot, "Trap D"
  3.4  Inconsistencies in Total Disk Space
  3.5  Application Install Fails with "Not Enough Space"
  3.6  Performance Problems With Two Devices on a Single Channel
  3.7  Install Diskettes or Utility Diskettes Hang on Boot (APAR JR12065)
  3.8  Additional Parameters For IDE Device Driver
  3.9  Very Large (128/137 Gb limit) Hard Drive Considerations (48 bit LBA)
  3.10 Very Large (512 Gb limit) Hard Drive Considerations
     3.10.1 Format Error Installing from Updated Diskettes
     3.10.2 Installation  Process Hangs  after Rebooting When  Installing from
            Updated Diskettes


  4  Removable media support
  4.1  Partitioned Removable Media
    4.1.1  Using Protected Media
    4.1.2  Assignment of Drive Letters
    4.1.3  Configuring Partition Support (OS2DASD)
    4.1.4  Ejecting the Media
    4.1.5  Limitations of Partitioned Removable Media Support
  4.2  Large Floppy Removable Media (LS-120 / LS-240)
    4.2.1  Limitations of LS-120 / LS-240 Support
  4.3 CD-ROM Device Manager (OS2CDROM.DMD)
  4.4 CD-RW Media Support in IBMIDECD.FLT and IBMATAPI.FLT
  4.5 Additional Parameters for IBMIDECD.FLT and IBMATAPI.FLT Driver

  5 Supported Chipsets, Known Restrictions and Limitations
  5.1 Supported Chipset Table
  5.2 Known Restrictions and Limitations
    5.2.1 Intel Chipsets Limitations
    5.2.2 VIA Chipsets Restrictions
    5.2.3 SiS Chipset Limitation
  5.3 Chipset Extended Detection Algorithm for Intel Chipsets
  5.4 Serial ATA for Intel Chipsets Considerations
  5.5 Intel 82801FR Support in IBM1S506.ADD

  6  Copyright and Trademark Information



   Prerequisite Support
  ________________________

  The Latest  OS2 Loader package from  DDPAK should be applied  to your system
  (or installation diskettes) prior to installing this IDEDASD package.


  1  Introduction
  _________________

  FixPak 35 (FP35) for  Warp 3 and FixPak 6 (FP6) for  Warp 4 extended support
  for fixed  Enhanced IDE drives  to sizes up  to 8.4GB and added  new caching
  HPFS and  FAT file system  support for removable  media drives such  as SCSI
  Syquest  Syjet 1.5GB  portable hard  drive and  the Iomega  jaz 1GB  and 2GB
  personal hard drives.

  This  package contains updates  to the  support in  FP35 and  FP6, extending
  support  to fixed  Enhanced IDE  drives first  past the  8.4GB  boundary and
  second past  the 512 Gb  boundary.  It also  fixes some other  problems, and
  adding additional documentation on  removable media support.  Beginning with
  FP40 and  FP10 OS/2 base  device drivers were  separated into a  Base Device
  Driver FixPak.

  File ddk_note.txt  contains programming  information related to  the drivers
  included into the IDEDASD package and can be used in addition to the DDK and
  SDK references.

  This package also contains extensions to OS2CDROM.DMD, providing support for
  multi-session CDROM media.

  The package also contains  an updated floppy diskette driver (IBM1FLPY.ADD),
  which corrects  a failure that occurs upon  a Resume on a  ThinkPad when the
  diskette drive is installed in the ThinkPad docking station.

  Previously  IDE CD-ROM  (also  CD-R,  CD-RW, DVD)  devices  were handled  by
  IBMIDECD.FLT and all  other ATAPI devices (like LS-120  and ZIP drives) were
  handled  by IBMATAPI.FLT.  Now all  ATAPI devices  are handled  by  a single
  driver, the IBMATAPI.FLT.  For  backward compatibility this package provides
  both  IBMIDECD.FLT and  IBMATAPI.FLT drivers.  In  fact, they  are the  same
  driver  and  if  both drivers  are  in  config.sys  only  the first  one  in
  config.sys will  remain loaded. It  is recommended to use  only IBMATAPI.FLT
  driver entry  and remove the IBMIDECD.FLT  entry from config.sys.  If you do
  not remove the  IBMIDECD.FLT entry from the config.sys,  the step in section
  2.4 must also be performed on the IBMIDECD.FLT entry.

  For  Warp   Server  Advanced  HPFS386   support  of  removable   media,  you
  additionally need LAN Server SelectPack IP_8508.

  These fixpaks are available  from http://ps.software.ibm.com/ under the link
  "Downloads and  News."  Install the  fixpaks first, carefully  following the
  instructions with the fixpaks; then  follow the directions in this README to
  install this package.

  If you are  attempting to install Warp 3  or Warp 4 for the first  time on a
  fixed hard drive greater than 4.3GB, then:

  1.  Follow the instruction on  "Updating the Installation Diskettes" in this
      README and use the new diskettes to install Warp.

  2.  Install FP35 for Warp 3 or FP6 for Warp 4.

  3.  Follow the instructions in this README to install this package.

  The file list for the package:

  - dasd16.dmd
  - dasd16.sym
  - dasd32.dmd
  - dasd32.sym
  - ddk_note.txt
  - ibm1flpy.add
  - ibm1flpy.sym
  - ibm1s506.add
  - ibm1s506.sym
  - ibmatapi.flt
  - ibmatapi.sym
  - ibmidecd.flt
  - ibmidecd.sym
  - ide16.ddp
  - ide32.ddp
  - os2cdrom.dmd
  - os2cdrom.sym
  - readme.txt



  2  Installation
  _________________

  2.1  Updating the Installation Diskettes
  ________________________________________

  If you are attempting to install Warp on a hard drive greater than 4.3GB, or
  your are  attempting to install Warp  Server for e-business on  a hard drive
  greater than 30GB, then the Installation diskettes must be updated.

  If  you are  intend to  install OS/2  on a  hard drive  greater than  512 Gb
  partitioned  by OS/2  without  OS2DASD.DMD parameter  /D:n  /BOOTABLE or  by
  non-OS/2 tool, you  should back up all data from the  all partitions on this
  drive,  then remove all  partitions from  the drive  and reboot,  before you
  start  installation process.   This is  because OS/2  cannot  currently make
  bootable  such a drive  with an  acknowledged capacity  larger than  512 Gb.
  Instead the  drive must first be  changed to use a  smaller logical geometry
  which  ignores  part of  the  true capacity.   This  backing  up process  is
  typically laborious for a drive which is  already in use; and this is why it
  is  important to make  an early  and deliberate  and selection  of /BOOTABLE
  versus /FULLSIZE  option for  each drive with  greater than 512  Gb capacity
  when using this version of OS2DASD.DMD on a new drive.

  1.  Make a backup copy of your Diskette 1 (D1).

  2.  Copy the  new versions of  IBM1S506.ADD, and IBMIDECD.FLT  device driver
      files onto your D1 diskette.

  3.  If the installation  diskettes are for Warp Server  for e-business, Warp
      Server for e-business  Convenience Pak, or Warp 4  Convenience Pak, copy
      the  DASD32.DMD  file  to  your  D1  diskette  as  (over  the  existing)
      OS2DASD.DMD.  Otherwise copy the DASD16.DMD  file to your D1 diskette as
      (over the existing) OS2DASD.DMD.

  4.  Modify the CONFIG.SYS file:
      
      a. Add the statement SET COPYFROMFLOPPY=1 to the CONFIG.SYS on D1.
      
      b. Add the parameters /D:n  /BOOTABLE to the line BASEDEV=OS2DASD.DMD in
         the CONFIG.SYS  on D1  (/D:n refers to  the intended boot  drive, see
         section 3.10 for  parameters details) for disks equal  or larger than
         512 Gb.

  5.  Start  the  installation  with  the  Installation  Diskette  and  follow
      instructions.

      NOTES:

      a. During  the installation  process  before rebooting your  system make
         sure that the device driver statements are in the CONFIG.SYS file and
         the new  versions of  the IBM1S506.ADD, IBMIDECD.FLT  and OS2DASD.DMD
         device drivers have been copied  to the \OS2\BOOT directory.  Use the
         date of the files to distinguish the newer versions.

      b. (Follow this note instructions  if your total disk capacity is larger
         than 512 Gb.)   During installation process, you will  be prompted to
         reinsert  all  diskettes  and  the  files will  be  copied  from  the
         diskettes to the hard drive.   After coping and before rebooting (you
         will see the message "Remove  the diskette and press Enter to restart
         the  workstation and  continue the  installation") you  must  exit to
         command  prompt  (using  F3)  and remove  duplicate  line  containing
         "BASEDEV=OS2DASD.DMD /D:n  /BOOTABLE" from ending  of the CONFIG.SYS.
         There should  remain the line "BASEDEV=OS2DASD.DMD" in  the middle of
         the CONFIG.SYS.
	 

  2.2  Updating a Previous Installed Warp System
  ________________________________________________

  1.  (Optional) Save the existing (old) level of drivers in your system.

      a.  Change Directory to the \os2\boot directory on your boot drive.

      b.  Rename the  drivers (for example, where the boot  drive is C:).  The
          IBMATAPI.FLT driver may not have been previously installed.

            [C:\os2\boot] rename IBM1S506.ADD  IBM1S506.ORG
            [C:\os2\boot] rename IBM1FLPY.ADD  IBM1FLPY.ORG
            [C:\os2\boot] rename IBMIDECD.FLT  IBMIDECD.ORG
            [C:\os2\boot] rename IBMATAPI.FLT  IBMATAPI.ORG
            [C:\os2\boot] rename OS2CDROM.DMD  OS2CDROM.ORG
            [C:\os2\boot] rename OS2DASD.DMD   OS2DASD.ORG

  2.  Open an  OS/2 Window and  enter the SYSLEVEL  X: (where X: is  your boot
      drive).  Look  for the  entry x:\OS2\INSTALL\SYSLEVEL.OS2 and  see which
      version  of OS/2  you  have  installed; for  example  "Version 4.00"  or
      "Version 4.50".

  3.  Device Driver Install

      o   (Warp 3, Warp Server) Open  the Device Driver Install program in the
          OS/2 System Folder/System Setup Folder.

      o   (Warp 4, Warp Server  for e-business) Open the Device Driver Install
          program in the OS/2 System/System Setup/Install-Remove Folder.

  4.  Point the Device Driver Install file dialogue to the directory where you
      have placed the new files in this package.

         If your version  of OS/2 is 4.00 or earlier,  select the driver named
         IBM IDE AND REMOVABLE MEDIA SUPPORT (V4.00).

         If your version of OS/2 is 4.50 or later, select the driver named IBM
         IDE AND REMOVABLE MEDIA SUPPORT (V4.50).

      Click on INSTALL.

  5.  Reboot the system.


  2.3  Recommended Parameters for IBM1S506.ADD
  _________________________________________
  
  For  normal functioning of  Extended WarmSwap  support IBM1S506.ADD  must be
  configured as follows:

        1.  Edit config.sys

        2.  Find the line with IBM1S506.ADD:
                   "BASEDEV=IBM1S506.ADD"

        3.  Add (if they aren't already there) the following parameters:
                   "BASEDEV=IBM1S506.ADD /A:n /U:m /ATAPI /FORCE"
            where n is adapter number and m is unit number. 

        4.  Save config.sys

        5.  Reboot

  Examples:
  "BASEDEV=IBM1S506.ADD /A:1 /U:0 /ATAPI /FORCE" enables swapping on 
        ThinkPad Ultrabay. 
  "BASEDEV=IBM1S506.ADD /A:2 /U:0 /ATAPI /FORCE" enables swapping on 
        DockingStation Ultrabay. 
  See section 3.8 for description of these parameters.


  2.4 Recommended Parameters for IBMATAPI.FLT and IBMIDECD.FLT
  ____________________________________________

  For normal  functioning of WarmSwap support IBMATAPI.FLT  must be configured
  as follows:

        1.  Edit  config.sys

        2.  Delete line with  IBMIDECD.FLT (see note below):
                    "BASEDEV=IBMIDECD.FLT"

        3.  Find the line with IBMATAPI.FLT:
                   "BASEDEV=IBMATAPI.FLT"

        4.  Add (if they aren't already there) the following parameters:
                   "BASEDEV=IBMATAPI.FLT /A:n /U:m /TYPES:CLZ"
            where n  is adapter number and  m is unit number.  Theymust be the
            same as for IBM1S506.ADD (see sect. 2.3 for details)

        5.  Save config.sys

        6.  Reboot

  Examples:
  "BASEDEV=IBMATAPI.FLT /A:1 /U:0 /TYPES:CLZ" enables swapping of LS-120, 
                    LS-240, ZIP, CD type devices in  ThinkPad Ultrabay. 
  "BASEDEV=IBMATAPI.FLT /A:2 /U:0 /TYPES:CLZ" enables swapping of LS-120, 
                    LS-240, ZIP, CD type devices in DockingStation Ultrabay.
  See section 4.5 for description of these parameters.

  Note: If you do not remove the IBMIDECD.FLT entry from config.sys, then step
        4 must also be performed on this entry.


  2.5  Recommended parameters for IBM1FLOPPY.ADD
  ______________________________________________

  To  enable external  and  ultrabay floppy  drive  functioning with  WarmSwap
  IBM1FLOPPY.ADD must be configured as follows:

        1.  Edit config.sys
	
        2.  Find the line with IBM1FLPY.ADD:
             "BASEDEV=IBM1FLPY.ADD"
	     
        3.  Add (if they aren't already there) the following parameters:
             "BASEDEV=IBM1FLPY.ADD /A:n /FORCE:2 /U:m /F:1.44MB /U:m /F:1.44MB"
         where n is adapter number and m is unit number.
	 
        4.  Save config.sys
	
        5.  Reboot

  Example:
  "BASEDEV=IBM1FLPY.ADD /A:0 /FORCE:2 /U:0 /F:1.44MB /U:1 /F:1.44MB"


  3  Large Hard Drive Considerations
  ____________________________________

  3.1  System Hang or Hard Drive Hesitation
  _________________________________________

  The  problem is  the IDE  chip sets  on certain  planars indicate  that they
  support Bus  mastering but  actually have a  defect that prevents  them from
  working  correctly.   The  driver  detects bus  mastering  support,  enables
  busmastering and attempts to use it.  Some symptoms are:

  o   System will not boot with IBM1S506.ADD.

  o   CHKDSK command does not work properly.

  o   Hard drive stops or hesitates for minutes at a time.

  This is  a known problem  with ThinkPad models 760E/ED/ELD/EL.   However the
  chip  set can,  and does,  show up  on planars  of other  manufacturers.  To
  correct:

  1.  Edit the CONFIG.SYS file on Diskette 1 or the boot drive.

  2.  Disable busmastering  by adding  the parameter /!BM  to the  driver; for
      example:

        BASEDEV=IBM1S506.ADD /A:0 /!BM /A:1 /!BM

  3.  Save the changes and reboot.


  3.2  Cannot Mark a Partition Installable
  ________________________________________

  There is a BIOS restriction  for most older (typically pre-2001 manufacture)
  computers  that  installable  (startable)  or bootable  partitions  must  be
  contained within the first 1024 logical cylinders of the disk.  This is true
  for  both EIDE  and  SCSI  hard disk  drives.   If FDISK  fails  to allow  a
  partition  to be  marked installable,  the  partition is  either above  1024
  cylinders or  the partition  spans the first  1024 logical cylinders  of the
  disk.  Use FDISK  to reduce the size of the  startable or bootable partition
  by sufficient MBytes.  One way to calculate the correct partition size is to
  do the following:

  1.  Edit  your   CONFIG.SYS  and  add  the   parameter  /W  or   /V  to  the
      BASEDEV=IBM1S506.ADD statement.

  2.  Save this change and reboot the system.

  3.  At initialization,  record the  far left hand  column of numbers  of the
      geometry  information  under the  OS2:log  heading;  for example,  where
      C=cylinder, H=head, and S=sector:

            OS2:log
       C       1027
       H         63
       S        128

  4.  Calculate the  1024 cylinder size in  MBytes as ( H  x S )  / 2.  (round
      down).

      All bootable  partitions must  be contained within  this size.   In this
      example  the bootable  partition must  be  contained in  the first  4032
      MBbytes of  the disk and cannot  exceed a single partition  size of 4032
      MBytes within  this area.  No  bootable partition may extend  beyond the
      first 4032 MBytes.

  5.  Use FDISK to resize the partitions and reboot.


  3.3  IPE on Boot, "Trap D"
  __________________________

  If  you experience  a Trap  D on  boot when  using the  /FORCE  parameter on
  IBM1S506.ADD, and  you have the  NetFinity client installed, REMark  out the
  BASEDEV=NFDASD.FLT statement in CONFIG.SYS.


  3.4  Inconsistencies in Total Disk Space
  ________________________________________

  This version of  IBM1S506.ADD allows the detection and  correct reporting of
  some additional free space on certain drives.  This "free space" is real and
  now can be  accessed, either by creating a new partition  or using a program
  such as PartitionMagic to add the free space to an existing partition.  This
  will not  cause any corruption or  inaccessibility to the  data currently on
  the disk.


  3.5  Application Install Fails with "Not Enough Space"
  ______________________________________________________

  FAT  partitions  under OS/2  are  limited to  a  2.1GB  maximum size.   HPFS
  partitions are limited  to a 64GB maximum size.  However  there is the magic
  number, 2,147,483,647 (2.1GB).  This 2.1GB  value is the maximum number that
  will  fit   into  a  signed  32-bit  integer.    Some  application  software
  installation programs query OS/2 about  the available remaining space on the
  partition and  save the result into  a signed 32-bit integer.   If more than
  2.1GB is available  there is an overflow, it appears  no space is available,
  and the installation program refuses to continue.  Two solutions are:

  o   Partition the remaining space into maximum 2GB partitions.

  o   Retain the large partition, but before trying to install software create
      a large temporary file that  reduces available space to less than 2.1GB.
      After installation of the application delete the temporary file.


  3.6  Performance Problems with Two Devices on a Single Channel
  ______________________________________________________________

  With  certain planars, two  devices attached  to the  same IDE  channel will
  exhibit performance problems when one device is a slow non-DMA device like a
  CDROM or  removable drive and the other  device is a faster  disk drive.  To
  alleviate this problem  move the slow device to the  other channel, where it
  is the only device or is paired with a similar slow device.

  If moving the device is not  possible, then you can disable busmastering for
  that  channel,  by  specifying  parameters  on the  driver  IBM1S506.ADD  in
  CONFIG.SYS.  For  example, if  you wanted to  disable bus mastering  for the
  secondary controller, you  would add  the parameters  "/A:1 /!BM"  to the
  IBM1S506.ADD line in CONFIG.SYS.


  3.7  Install Diskettes or Utility Diskettes Hang on Boot (APAR JR12065)
  _______________________________________________________________________

  Diskette 1  of the Install  or Utility diskette  sets may appear to  hang on
  boot, waiting for a removable media device to respond.  To avoid:

  1.  Edit the CONFIG.SYS on Diskette 1 of the set

  2.  REMark out the basedev=ibmint13.i13 statement and save the file.

  3.  Reboot


  3.8  Additional Parameters for IDE Device Driver
  ________________________________________________

  PARAMETER      FUNCTION

  /V             Verbose  Mode, displays controller status  and drive geometry
                 information during OS/2 initialization.

  /VL            Same  as  /V  but  does not  display  drive  geometry.   This
                 parameter  is added  to  avoid the  message buffer  overflow,
                 resulting in a "Lost message" message.

  /V:x           Verbose  Mode, displays controller status  and drive geometry
                 information only for  selected adapter x. The x  value can be
                 from 0  to 4.  This parameter is  added to avoid  the message
                 buffer overflow, resulting in a "Lost message" message.

  /W             Verbose  Mode, displays controller status  and drive geometry
                 information during OS/2 initialization.  Initialization stops
                 after  displaying the  information  for each  device, with  a
                 "Press Enter  to Continue" message.  It is  possible that the
                 message buffer  will overflow, resulting in  a "Lost message"
                 message.  This parameter works  correctly on Warp 3 with FP35
                 or later systems and on Warp 4 systems with FP6 or later.

  /WL            Same as  /VL, only  with pause.   Initialization  stops after
                 displaying  the information  for each  device, with  a "Press
                 Enter to Continue" message.

  /W:x           Same as  /V:x, only  with pause.  Initialization  stops after
                 displaying  the information  for each  device, with  a "Press
                 Enter to Continue" message.

  /FORCE         Forces the  emulation of an IDE CDROM  drive, even though one
                 is not present during  OS/2 initialization.  For example, the
                 statements

                   BASEDEV=IBM1S506.ADD /A:1 /U:0 /ATAPI /FORCE
                   BASEDEV=IBMIDECD.FLT

                 support inserting  an internal CDROM drive  into the Ultrabay
                 of a ThinkPad  755CD after suspend, even though  the drive is
                 not present during initialization.

  /UDMA:x        If  the system  is Ultra DMA  capable, this parameter  may be
                 used  to  limit the  highest  UDMA  mode  for an  adapter  or
                 device. The limit is specidied  by "x", the value can be from
                 0 to  5. If  the specified value  is higher than  the maximum
                 UDMA capability  the parameter  is ignored. For  example, the
                 statement

                    BASEDEV=IBM1S506.ADD /A:1 /U:0 /UDMA:2

                 limits Ultra DMA mode for secondary channel master device to
                 Ultra DMA mode 2.
                 
  /!UDMA         This parameter  is used  to disable  Ultra DMA  modes  of Bus
                 Mastering but  leave BM DMA  modes enabled. For  example, the
                 statement

                    BASEDEV=IBM1S506.ADD /A:0 /U:1 /!UDMA

                 disables Ultra DMA mode for primary channel slave device.

  /BM            If the  system is DMA capable, this parameter  can be used to
                 enable  or disable  DMA for  a specified  device  or adapter.
                 Example: "/A:1  /U:0 /BM" enables  DMA for the  Master device
                 attached to the secondary IDE  channel. This can be useful to
                 enable DMA on  ATAPI devices ( CD-ROM, LS120,  ZIP, etc) that
                 are  defaulted to  run  in PIO  mode.   If a  device is  UDMA
                 capable, using the "/BM"  or "/UDMA" parameter is recommended
                 only if  the IDE 80 pin  flat cable is  connected (instead of
                 the normal 40 pin flat  cable).  See section 5 for details on
                 various chipsets.

  /!BM           This  parameter is used to  disable Bus Mastering  DMA for an
                 adapter or device. For example, the statement
                 
                    "BASEDEV=IBM1S506.ADD /A:1 /!BM" 
                       disables BM DMA for secondary IDE channel,
                    "BASEDEV=IBM1S506.ADD /A:0 /U:1 /!BM"
                       disables  BM  DMA  for  master device  on  primary  IDE
                       channel

  /!HC           This  parameter is used  to disable a drive's  internal write
                 cache. When this parameter is specified and a write is issued
                 to the device, the drive will write directly to the media and
                 will not return until the  data has been written to the media
                 For example, the statement

                    "BASEDEV=IBM1S506.ADD /A:0 /U:0 /!HC"
                        disables write cache for  the device located at Unit 0
                        on the Primary Adapter,
                    "BASEDEV=IBM1S506.ADD /A:0 /!HC"
                        disables  write cache  for all  units attached  to the
                        Primary Adapter.
                 
  /HC           This parameter  is  used  to enable  device  write cache.   In
                general  this  parammter  should  not be  needed  because  the
                default  is  Device Write  Cache  enabled.   For example,  the
                statement

                    "BASEDEV=IBM1S506.ADD /A:0 /U:1 /HC"
                        enables  write  cache  for  the slave  device  on  the
                        Primary Adapter,
                    "BASEDEV=IBM1S506.ADD /A:1 /HC"
                        enables  write cache  for  all units  attached to  the
                        Secondary Adapter.

  /!BIGLBA       Disables 48  bit LBA support for specified  drive. Drive size
                 will be limited to 128 (137) Gb and legacy LBA 28 bit support
                 will be used. See section 3.10 for details. Examples:
                 
                    "BASEDEV=IBM1S506.ADD /A:0 /U:0 /!BIGLBA"
                       disables  48  bit  LBA  support for  master  device  on
                       primary IDE channel,
                    "BASEDEV=IBM1S506.ADD /A:1 /U:1 /!BIGLBA"
                       disables  48  bit  LBA  support  for  slave  device  on
                       secondary IDE channel.
                                                          
  /CDA          Enables   Chipset  Extended  Detection   Algorithm  for  Intel
                chipsets. Example:

                    BASEDEV=IBM1S506.ADD /CDA

                Enables detection of newer Intel PCI IDE chipset as the latest
                described in  the supported chipset table in  section 5.1. See
                section 5.3 for  additional information about Chipset Extended
                Detection Algorithm.

  /!SAL         Disables  SMART   (Self-Monitoring,  Analysis,  and  Reporting
                Technology)  Auto Logging  for the  device.  This  switch will
                disable SMART  Auto Logging only  for the device. It  does not
                have an affect on any of the other SMART commands.

                Example:
 
                    BASEDEV=IBM1S506.ADD /A:0 /U:0 /!SAL


  3.9  Very Large (128/137 Gb limit) Hard Drives Considerations (48 bit LBA)
  ____________________________________________________________________________

  Legacy LBA  (also know as 28 bit  LBA) maximum drive capacity  is limited to
  137 GB (268,435,455 sectors by 512  bytes each).  The 48 Bit LBA support was
  introduced  to break this  barrier and  provide support  for hard  disk with
  capacities larger than 137 GB.

  This version of  the IBM1S506.ADD driver has the 48 bit  LBA support and the
  driver will  automaticaly detect drives with  the capability of  48 bit LBA.
  This 48 bit LBA support will allow the  use of hard disk drives with up to 2
  TB (Terabytes) (1 TB = 1024 GB) capacity.

  In  spite of  the original  removal of  the 28  bit restriction,  before the
  addition of 512 Gb logical geometry support, the OS2DASD.DMD driver also had
  a geometry imposed  limitation which limited the maximum  physical hard disk
  capacity which OS/2 could support to 512 Gb.
  
  To maintain backward compatibility a new config.sys parameter,"/!BIGLBA", is
  introduced. If "/!BIGLBA"  is specify in config.sys, this  parameter for the
  specfic drive will  disable 48 bit LBA support and will  revert to legacy 28
  bit LBA  and usable drive  capacity will be  limited to 137  GB (268,435,455
  sectors by  512 bytes  each). If  the drive is  partitioned when  using this
  switch, then it will be compatible when connected to a system without 48 bit
  LBA support.  See section 3.8 for the "/!BIGLBA" parameter syntax.

  3.10 Very Large (512 Gb limit) Hard Drive Considerations
  ________________________________________________________
 
  The previous version  of OS2DASD.DMD had a 512  Gb geometry limitation which
  allowed only part (remainder of the  total drive capacity divided by the 512
  Gb) of the hard drive to be accessible for the system.

  The  current version  of OS2DASD.DMD  removes  this limit  and allows  total
  capacity  of the  hard drive  up to  2 Tb.  This support  has  the following
  options:

  1.  If the  drive is used as  a boot drive, only  first 512 Gb  of the drive
      space will be accessable to the system.

  2.  If drive is used only as a  data storage drive the total capacity (up to
      2 Tb) of drive will be accessable to the system.

      The two new parameters are available to select these options:

  o /BOOTABLE --- applied to  the unpartitioned large drive (during the bootup
      prior to the first partitioning  of the drive) and makes drive bootable,
      but limiting its available capacity to 512 Gb.

  o /FULLSIZE --- applied to  the unpartitioned large drive (during the bootup
      prior to the first partitioning of the drive) and allow use of the total
      capacity of  the drive (up to 2  Tb), but prevents the  drive from being
      made bootable.

  The parameters have the following usage syntax:

  BASEDEV=OS2DASD.DMD [/D:n] [/BOOTABLE | /FULLSIZE]

  where  /D:n  denotes the  number  of  the drive  (/D:0  is  drive 0,  etc.).
  Parameter /BOOTABLE  or /FULLSIZE following /D:n  is applied to  drive n. If
  for some  drive value n  (n>0) the /D:n  parameter is omitted  the following
  parameter (/BOOTABLE  or /FULLSIZE) is  applied to the first  drive (default
  /D:0).   If parameter  /BOOTABLE or  /FULLSIZE  for some  drive is  omitted,
  /FULLSIZE is applied for this drive by default.

  If drive  is larger than 512 Gb,  then LVMUPDT package must  be installed in
  addition to the IDEDASD package to access the full drive capacity (/FULLSIZE
  option). If drive  is not larger than 512 Gb that  IDEDASD package is enough
  to access the  full drive capacity, but LVMUPDT package  may be installed in
  addition.

  3.10.1 Format Error While Installing from Updated Diskettes
  ___________________________________________________________

  If  you  get a  format  error message  while  installing  OS/2 from  updated
  diskettes, check whether you have the following line in the CONFIG.SYS:

  BASEDEV=OS2DASD.DMD /D:n /BOOTABLE

  If instead you have the line: BASEDEV=OS2DASD.DMD

  without the parameter  /BOOTABLE for the intended boot  drive /D:n, then you
  will need to:

  1) Stop your current installation of OS/2

  2) Backup any data which you intend  to preserve from the all the partitions
     on the intended boot drive /D:n which you intend to preserve

  3) Remove all the partitions on the intended boot drive /D:n

  4) Reboot 

  5) Modify your CONFIG.SYS file on the  D1 diskette to add /D:n /BOOTABLE, if
     it is not there already

  6) Restart the installation process of OS/2 from the beginning

  7) Restore backed up data to new partitions using the new logical geometry

  Since all this backing up  and restoring is typically quite inconvenient, it
  is highly advisable  to decide quite deliberately whether  or not you intend
  to use your large  drive as a boot drive before you  partition it and modify
  your  CONFIG.SYS  file  on  your  D1  diskette  accordingly,  as  previously
  documented.


  3.10.2  Installation  Process Hangs  after  Rebooting  When Installing  from
          Updated Diskettes
  ____________________________________________________________________________


  If  the installation  process  hangs after  rebooting  when installing  from
  updated diskettes, then see section  3.10.1 for possible reason and recovery
  instructions.

  4  Removable Media Support
  __________________________

  Removable media devices attach to the system by a variety of interfaces.

  IDE       Supported with the OS/2 supplied IBM1S506.ADD device driver.

  EIDE      Supported with the OS/2 supplied IBM1S506.ADD device driver.

  ATAPI     Supported with the OS/2 supplied IBMATAPI.FLT device driver.

  ATA       Supported  with  the  OS/2 supplied  IBM1S506.ADD  device  driver.
            Iomega Zip ATA drives are supported only as single partition media
            and be configured in ATA  Compatibility Mode; that is, the jumpers
            are:

                    Master             Slave
                                                          

  SCSI      Small Computer System  Interface.  Supported with the  OS/2 device
            driver for  the SCSI controller  to which the device  is attached.
            Many SCSI drivers  are supplied with OS/2.  If  your device is not
            recognized  you must  acquire the  proper device  driver  from the
            vendor.                                                    Consult
            http://service.software.ibm.com/os2ddpak/html/diskands/index.htm.
            To ensure  correct operation with  the Adaptec 1542  SCSI adapter,
            partition sizes should always be less than 1GB.

  PP        Parallel Port attached  devices are supported with vendor-supplied
            drivers.  The device driver must  have an ".ADD" extension for the
            media to be supported  as partitioned removable.  For example, the
            Syquest  Syjet  Parallel  drive   is  properly  supported  by  the
            vendor-supplied EPST.ADD  driver, the  Iomega Zip Parallel  uses a
            vendor-supplied  *.SYS   driver  and  is  not   supported  by  the
            partitioned  removable  support, and  the  Syquest SparQ  Parallel
            Iomega ZipPlus Parallel drives have no OS/2 drivers at all.

  USB       Floppy  and  removable  media  devices  (including  CDROM,   CD-RW
            devices) are  supported with  the OS/2 supplied  USBMSD.ADD device
            driver and special CDROM class device driver USBCDROM.ADD.

  Removable media devices are supported in one of two ways.

  LARGE FLOPPY        The LS-120 / LS-240 drive.

  PARTITIONED         All other magnetic  removable media devices.  This media
                      appears as a removable hard drive.


  4.1  Partitioned Removable Media
  ________________________________

  Features of the partitioned removable media support are:

  o   Ability to partition removable media into multiple partitions

  o   Ability to format with either HPFS or FAT

  o   Ability to exploit caching performance

  o   Ability to use HPFS long file names

  o   Drag/drop capability through the Workplace drive icon

  o   Operating system protection to safely eject media through software eject
      utility

  o   Assignment  of drive  letters to  end of disk  drive lettering  chain to
      prevent floating drive letters

  o   Ability  to predetermine  a fixed number  of drive letters  for multiple
      partitions for removable media

  4.1.1  Using Protected Media

  There are some restrictions on the use of these devices.  These restrictions
  deal  with vendor-provided  protection  routines that  either read/write  or
  password protect the media.

  You are  unable to read  or write HPFS  formatted media that has  been read,
  write or  password protected by  a vendor supplied protection  utility.  For
  all read  and write protected media,  remove the vendor  protection prior to
  trying to read  or write to the  media.  For instance, if you  do not remove
  the protection, you will get the following failures:

  o   If  you issue a  DIR command to  write or password protected  media, you
      will receive a "Drive improperly stopped" error message.

  o    If you try  to FORMAT  a write  or password  protected media,  you will
      receive numerous error messages after a few minutes.

  o   If you  try to use desktop operations  like drag/drop folders/files, you
      will receive numerous error messages.

  Once the  vendor supplied protection is  removed, then these  errors will no
  longer occur.

  4.1.2  Assignment of Drive Letters

  New Algorithm: no filters assumed

     Primary from fixed disk 1
     Primary from fixed disk 2

     Primary from fixed disk n
     Extended from fixed disk 1
     Extended from fixed disk 2

     Extended from fixed disk n
     Primary from removable disk 1
     Extended(s) from removable disk 1
     Primary from removable disk 2
     Extended(s) from removable disk 2

     Primary from removable disk n
     Extended(s) from removable disk n

  Lack of a primary partition (or  Extended Partition only) is allowed.  If no
  media is  present at boot,  a single logical  drive is reported.   Note that
  some drives,  Syquest EZ135A  for example, do  NOT report correctly  when no
  media  is present  and will  not be  seen at  all.  If  media  with multiple
  partitions is  present at boot, then  all partitions will  be assigned drive
  letters.

  4.1.3  Configuring Partition Support (OS2DASD)

      BASEDEV=OS2DASD.DMD [/LF] [/MP:(disk,count)[,(disk,count)]]

  PARAMETER      DESCRIPTION

  /LF            Forces  all removable devices  to be treated as  Large Floppy
                 rather than partitioned media.

  /MP            Used  to support allocating  a predetermined number  of drive
                 letters for a partitioned  removable media device.  Note that
                 this  option only applies  to partitioned  removable devices,
                 and is ignored for any other device type.

  If the /MP parameter is used, then:

  SUB-PARAMETER  DESCRIPTION

  DISK           The integer disk number  of the device, as reported by FDISK,
                 or  the  wildcard  character  * to  specify  all  partitioned
                 removable devices.

  COUNT          The integer count of  the number of partitions to reserve for
                 the  device.   If  the  wildcard  character  *  is  used,  it
                 specifies a  default number of  drive letters to  reserve for
                 all partitioned removable devices.   Specifying a count for a
                 particular disk  will override this default.   Also, if there
                 is  media  in  the device  at  boot  time,  and it  has  more
                 partitions which  are eligible to receive  drive letters than
                 there are  drive letters reserved for the  device through the
                 /MP option, then the

                 number of drive letters reserved for the device will be
                 increased so that every eligible partition on the media will
                 have a drive letter.

  If the /MP option is not used, the rules for determining the number of drive
  letters reserved for a partitioned removable media device are as follows:

  o   If  there is no  media in the  drive at boot time,  or the media  in the
      drive has no valid partitions, then one drive letter is reserved for the
      device.

  o   If  there is media  in the drive  at boot time  and the media  has valid
      partitions which  are eligible  for drive letters,  the number  of drive
      letters  is equal to  the number  of eligible  partitions on  the media.
      Media which is formatted in floppy mode is treated as a single partition
      and allocated a single drive letter.

  4.1.4  Ejecting the Media

  OS/2 prevents  the media from being  ejected during data  transfers or while
  there are  pending file transactions.   The hardware manual eject  button is
  disabled during these times. The eject button will be enabled when the media
  can be safely ejected.

  There is a new OS/2 utility,  EJECT.EXE, that provides a command line method
  for ejecting the media.  The  Workplace Drive Icon now supports the software
  eject option  for these drives as  well. For example, the  command EJECT J:,
  where J: is the  logical drive letter of one of the  partitions on the media
  will cause the media to be ejected.

  In order for this  command to succeed there must be no  open files on any of
  the  partitions on  the media,  nor any  open search  operations.  Removable
  media that  is shared  on a server  cannot be  ejected because of  open file
  handles.  If it  is necessary to remove the media  without rebooting you may
  issue the command CHKDSK J: /F, where  J: is the logical drive letter of one
  of the partitions  on the media.  This will free the  media and a subsequent
  EJECT J: command will cause the media to be ejected.

  4.1.5  Limitations of Partitioned Removable Media Support

  o   Applications that manipulate partitioned devices, such as file managers,
      must be updated to test the fixed/removable flag in order to account for
      partitioned  removable devices.   Such applications  that have  not been
      updated  treat  the removable  devices  as  fixed  and the  results  are
      unpredictable whenever media is not present.

  o   Due  to the  variability of hardware  adapter support, installing  to or
      booting from partitioned removable media is not supported.

  o   Optical drive support  is unchanged.   Partitioned  removable  media and
      HPFS  do  not  support  optical  drives.  You  should  continue  to  use
      OPTICAL.DMD and OS2SCSI.DMD.

  o   The  following  devices  were  tested  during  the  development  of  the
      Partitioned  Removable Media  Support.  Similar  devices  should operate
      correctly,  as  should  other  removable  media devices  that  are  made
      available with a supporting ADD device driver.

      -   Iomega SCSI jaz 1GB and 2GB personal hard drives

      -   Iomega Zip ATA 100MB drives (supported only as single partition
          media).

      -   Iomega Zip ATAPI 100 MB drives

      -   Iomega Zip ATAPI 250 MB drives

      -   Syquest SCSI Syjet 1.5GB portable hard drives

      -   Syquest IDE Syjet 1.5GB portable hard drives

      -   Syquest SparQ IDE portable hard drives


  4.2  Large Floppy Removable Media (LS-120 / LS-240)
  ___________________________________________________

  The LS-120 drive  supports 120-MB diskettes and is  compatible with 3.5 inch
  1.44-MB  standard diskettes,  with improved  performance.  The  LS-240 drive
  supports 240-MB diskettes,  120-MB diskettes and is also  is compatible with
  1.44-MB standard diskettes.

  4.2.1  Limitations of LS-120 / LS-240 Support

  o   If you have an LS-120 drive as drive B, then you must not format it from
      an OS/2 windowed or full screen session where the current drive is drive
      A or  drive B.  The current drive  for an  OS/2 windowed or  full screen
      session is  given as part  of the command  prompt.  For example,  if the
      command prompt in an OS/2 windowed or full screen session is [C:\], then
      drive C is the current drive.

  o   If  an LS-120  drive is installed  in a  ThinkPad docking station  and a
      CD-ROM or  DVD drive  is in the  system UltraBay,  you may get  an error
      message  "A program  in this  session encountered  a problem  and cannot
      continue." when a DOS window is opened. In this case edit the config.sys
      file  and move  the statement  BASEDEV=IBMIDECD.FLT so  that  it appears
      before the statement BASEDEV=IBMATAPI.FLT in the file.

  o   The  following devices were tested  during the development  of the Large
      Floppy  Removable   Media  Support.   Similar   devices  should  operate
      correctly.

      -   Imation LS-120

      -   SuperDisk LS-120

      -   SuperDisk LS-240


  4.3  CD-ROM Device Manager (OS2CDROM.DMD)
  _________________________________________
  
  The   CD-ROM   Device   Manager   (OS2CDROM.DMD)  has   several   additional
  features. These  features are described  in file ddk_note.txt. This  file is
  included into this IDEDASD package.
  


  4.4  CD-RW Media Support in IBMIDECD.FLT and IBMATAPI.FLT
  _________________________________________________________

  IBMIDECD.FLT and  IBMATAPI.FLT now supports  IDE CD-Writers for  reading and
  writing.


  4.5  Additional Parameters for IBMATAPI.FLT and IBMIDECD.FLT Driver
  ___________________________________________________________________

  PARAMETER      FUNCTION

  /V             Verbose Mode, displays filter status on detected and emulated
                 devices.

  /A:n           Specify  adapter:  0=primary,  1=secondary,  2=DockingStation
                 primary, 3=DockingStation secondary.

  /I             Ignore  adapter n  specified  by  /A:n.   Example: "/A:1  /I"
                 secondary IDE channel will not be filtered.

  /U:n           Specify unit: 0=master, 1=slave.

  /!U:n          Specified unit will be ignored. Examples: "/A:1 /!U:1" ignore
                 (not  claim)  slave unit  on  secondary  IDE channel.   "/A:2
                 /!U:0" ignore (not claim) DockingStation UltraBay.

  /SCSI          Export IDE device as SCSI device. Can be used to emulate SCSI
                 CD-RW device as IDE  CD-RW device. Example: "/A:1 /U:0 /SCSI"
                 will report SCSI CD  device attached as secondary IDE channel
                 master unit .

  /TYPES:xxx     Specify  device types  supported by WarmSwap.  x can  be C=CD
                 (CD-ROM, CD-R, CD-RW, DVD, etc), L=LS (LS-120, LS-240), Z=ZIP

                 Examples:
                 "/A:1 /U:0 /TYPES:CLZ" enable swapping between CD, LS and ZIP
                 "/A:1 /U:0 /TYPES:CZ" enable swapping only between CD and ZIP

                 If certain device  is in the UltraBay during  Boot it will be
                 enabled for swapping.

  /C             IBMATAPI.FLT and IBMIDECD.FLT have been modified so that they
                 no longer  fill the request's Scatter/Gather  (S/G) list with
                 0's for  the commands without  a data tranfer phase,  even if
                 the particular  command contains a valid S/G  list.  To avoid
                 possible unforseen compatibility problems with older drivers,
                 the /C parameter can be used to disables this new behavior.



  5 Supported IDE Controllers, Known Restrictions and Limitations
  _________________________________________________________________

  5.1 Supported Chipset Table
  ___________________________

  The OS/2 IDE Controller Adapter Device Driver (IBM1S506.ADD)
  supports the following PCI IDE Controllers

  ---------------------------------------------------------------
  |Controller|   Controller Info    |  Highest |  Comments      |
  |   Name   |                      |   UDMA   |                |
  ---------------------------------------------------------------
  |CMD640    | First CMD640         |     -    |                |
  |RZ1000    | First RZ1000         |     -    |                |
  |I82371FB  | INTEL82371FB         |     -    |                |
  |PIIX3     | Intel PIIX3 IDE      |     -    |                |
  |ORION     | INTEL_ORION          |     -    |                |
  |PIIX4     | Intel PIIX4 IDE      |  ATA 33  |                |
  |I82801AA  | Intel 82801AA IO HUB |  ATA 66  |See sec.  5.2.1 |
  |I82801AB  | Intel 82801AB IO HUB |  ATA 33  |                |
  |I82801BA  | Intel 82801BA IO HUB |  ATA 100 |See sec.  5.2.1 |
  |I82801CA  | Intel 82801CA IO HUB |  ATA 100 |See sec.  5.2.1 |
  |I82801DB  | Intel 82801DB IO HUB |  ATA 100 |See sec.  5.2.1 |
  |I82801EB  | Intel 82801EB IO HUB | SATA 150 |See sec.  5.4   |
  |I82801FB  | Intel 82801FB IO HUB | SATA 150 |See sec.  5.4   |
  |I82801FR  | Intel 82801FR IO HUB | SATA 150 |See sec.  5.5   |
  |CMD646    | CMD 646 PCI to IDE   |  ATA 33  |                |
  |CMD648    | CMD 648 PCI to IDE   |  ATA 66  |                |
  |VIA586B   | VIA 586B PCI to IDE  |  ATA 33  |See sec.  5.2.2 |
  |VIA596B   | VIA 596B PCI to IDE  |  ATA 66  |See sec.  5.2.2 |
  |VIA686A   | VIA 686A PCI to IDE  |  ATA 66  |See sec.  5.2.2 |
  |SIS630    | SIS 630 PCI to IDE   |  ATA 66  |See sec.  5.2.3 |
  ---------------------------------------------------------------


  5.2 Known Restrictions and Limitations
  ______________________________________

  This section covers some restrictions and/or limitation for the IBM1S506.ADD
  driver. These restrictions are mainly due to hardware problems.

  DMA for ATAPI devices is disabled by default. The exception to this is ATAPI
  devices on  Intel I82801AA chipset  and later Intel chipsets  (including all
  SATA controllers).  DMA for the ATAPI device can be enabled manualy by using
  the "/BM"  parameter. (To enable it  see sec. 3.8) Example:  "/A:1 /U:0 /BM"
  enables DMA for the Master device attached to the secondary IDE channel.

  If a  device is UDMA capable,  using "/BM" parameter is  recommended only if
  the IDE 80  pin flat ribbon cable  is used (instead of standard  40 pin flat
  cable).

  The IBM xSeries 226 with the optional ServeRaid 6i adapter will not work with
  the IDE (Parallel and/or Serial ATA)  hard drives enabled. When trying to use
  the ServeRaid adapter with the IDE hard drives enabled simultaneously, a Trap
  D system error will occur  during  system boot.  This restriction  applies to
  hard drives (HDD) only and does not apply to ATAPI devices (CD, DVD, etc).
  To avoid this  system error either  disable the HDD attached IDE controllers,
  remove the IDE HDD drives  from the system or remove  the ServerRaid  adapter
  from the system.


  5.2.1 Intel Chipsets Limitations
  ________________________________

  o   for the  82801AA, 82801BA and 82801BA Mobile chipsets  where there are 2
      devices on a channel, the fastest UDMA mode will be limited to UDMA 2.

  o   on some  systems with 82801DB and later chipsets  there is problems with
      proper 80 pin  cable detection.  To avoid problems  with cable detection
      use only  80 pin  IDE cables.  The  80 pin  cable are a  requirement for
      devices to operate in UDMA mode  and are usually installed in the system
      when the  drive and  system support UDMA.   If you  use 40 pin  cable on
      primary  or  secondary  channel,  specify  the  parameter  "/UDMA:2"  in
      CONFIG.SYS for that channel.  Usage of this parameter is described above
      (see sec.   3.8).  Examples:  use "/A:0  /UDMA:2" if you  have a  40 pin
      cable on  the primary channel  use "/A:1 /UDMA:2"  if you have a  40 pin
      cable on  the secondary channel use  "/A:0 /UDMA:2 /A:1  /UDMA:2" if you
      have a 40 pin cable on both channels

  o   for 82801  series  chipsets  (including all  SATA  controllers) DMA  is
      enabled for ATAPI  devices by default.  It can  be disabled using "/!BM"
      parameter (see  sec.  3.8). Example:  "/A:1 /U:0 /!BM" disables  DMA for
      Slave  device  attached to  secondary  IDE  channel.   "/A:1 /U:1  /!BM"
      disables DMA for Slave device attached to secondary IDE channel.

  5.2.2 VIA Chipsets Restrictions
  _______________________________

  The  IBM1S506.ADD driver  has  the  following limitations  for  the VIA  IDE
  controllers listed above:

  o   all of the VIA chipsets have  a problem with 80 pin cable detection.  To
      avoid problems with cable detection use  only 80 pin IDE cables.  The 80
      pin cable are a requirement for  devices to operate in UDMA mode and are
      usually installed in the system  when the drive and system support UDMA.
      If you  use 40 pin  cable on primary  or secondary channel,  specify the
      parameter  "/UDMA:2"  in CONFIG.SYS  for  that  channel.  Usage of  this
      parameter is described above (see sec. 3.8).

      Examples:
      use "/A:0 /UDMA:2" if you have a 40 pin cable on the primary channel 
      use "/A:1 /UDMA:2" if you have a 40 pin cable on the secondary channel 
      use  "/A:0 /UDMA:2 /A:1  /UDMA:2" if  you have  a 40  pin cable  on both
      channels

  o   any VIA chipset, which is not  listed above, but has the same PCI Device
      ID, will  be detected  as a  VIA586B and UDMA  performance mode  will be
      limited to UDMA 2 for any device that can operate above UDMA Mode 2.

  5.2.3 SiS Chipset Limitations
  _____________________________

  For SiS IDE  controllers listed above the following  restrictions applies:

  o   If  there is a UDMA  device on the SiS  Secondary channel and  an 80 pin
      ribbon cable is  not detected, then the driver will  limited the mode to
      PIO for this channel.

  o   Some  systems  with  SiS  chipsets  may be  unable  to boot  from a  FAT
      partition if the Hard Drive capacity is larger than 32GB.  In this case,
      you can either boot from an  HPFS partition or change your BIOS settings
      to disable "Block mode" for this drive in the system's setup.


  5.3. Chipset Extended Detection Algorithm for Intel Chipsets
  ____________________________________________________________

  The  IBM1S506.ADD  driver can  automatically  detect  all  PCI IDE  chipsets
  described in section 5.1 and enables the highest possible DMA/UDMA modes for
  all drives. Because Intel's  chipsets provide good backward compatibility it
  is possible to  detect a newer chipset  and use it as the  latest known one.
  To  use this  feature,  this support  must be  enabled  by the  user with  a
  config.sys parameter  "/CDA". If this parameter is  specified, then Extended
  Detection Algorithm will be enabled  and newer Intel chipset can be detected
  as the latest chipset described  in the supported chipset table (see section
  5.1) and higher possible DMA/UDMA modes can be properly detected and enabled
  for all drives attached to that chipset.

  If a system hang or trap occurs  when this parameter is used, then it should
  be removed from config.sys and legacy detection mode should be used for that
  chipset.


  5.4. Serial ATA for Intel Chipsets Considerations
  _________________________________________________

  The IBM1S506.ADD driver automatically  detects Intel Serial ATA and Parallel
  ATA controllers  described in section  5.1 and enables the  highest possible
  DMA/UDMA modes for  all drives. For PATA devices (know  also as standard IDE
  devices or ATA devices) the  maximum transfer rate for Intel IDE controllers
  is ATA100.  For SATA  devices this is  SATA150. For SATA  devices parameters
  /UDMA:n  and /!UDMA  (see  section 3.8  for  details) have  no effect.  SATA
  devices in  DMA mode  will always operate  in the maximum  possible transfer
  rate.


  5.5. Intel 82801FR support in IBM1S506.ADD
  __________________________________________

  IBM1S506.ADD driver support 82801FR (ICH6R)  only if it's RAID controller is
  configured to operate  as an IDE controller by the system  BIOS. If ICH6R is
  configured  to  operate as  RAID,  then IBM1S506  will  not  detect it.  The
  IBM1S506 driver does not support any RAID functionality.


  6  Copyright and Trademark Information
  ________________________________________

  The  following  terms  are  trademarks of  International  Business  Machines
  Corporation in the United States and/or other countries:
        IBM
        OS/2
        ThinkPad
        Ultrabay
        Warp
        Warp Server
        Warp Server for e-business
  Other company, product, and service names may be trademarks or service marks
  of others.

  THE INFORMATION PROVIDED IN THIS README IS PROVIDED "AS IS" WITHOUT WARRANTY
  OF ANY  KIND.  IBM DISCLAIMS  ALL WARRANTIES, WHETHER EXPRESSED  OR IMPLIED,
  INCLUDING  WITHOUT  LIMITATION, THE  IMPLIED  WARRANTIES  OF  FITNESS FOR  A
  PARTICULAR PURPOSE  AND MERCHANTABILITY WITH  RESPECT TO THE  INFORMATION IN
  THIS DOCUMENT.  BY FURNISHING THIS DOCUMENT,  IBM GRANTS NO  LICENSES TO ANY
  PATENTS OR COPYRIGHTS.

  (C) Copyright IBM Corporation, 2001, 2005. All rights reserved.
  U.S. Government  Users Restricted Rights  -- Use, duplication  or disclosure
  restricted by GSA ADP Schedule Contract with IBM Corp.