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      STACKER NOTE                                         STACKER NOTE
                          CONFIGURING CD-ROM DRIVES
                  (Applies to Stacker for OS/2 & DOS ver 4)
      STAC FAX  64402 (1/95)
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      BACKGROUND
      
      If you are setting up a CD-ROM on a Stacker drive, you may have
      to consider two different operating systems, OS/2 and DOS, if you
      are using Dual Boot or Boot Manager.
      
      SOLUTION
      
      - Correct Driver versions in OS/2
      - Configuration in DOS
           
      CORRECT DRIVER VERSIONS IN OS/2
      
      IBM has officially released certain CD-ROM drivers for use with
      OS/2. The first driver (named CDROM.SYS) was released with OS/2
      2.0; it supported only some IBM and Toshiba CD-ROM drives. The
      second driver, released with OS/2 2.1, supported a broader range
      of CD-ROM drives. Additional drivers were released with the
      Corrective Service Disks for OS/2 2.1. And OS/2 Warp has broader
      support yet.
      
      These drivers are "device=" block drivers, even though the one
      shipped with OS/2 2.1 is named OS2CDROM.DMD.  They can be placed
      either above or below the Stacker driver, which affects the drive
      letter assigned to the CD-ROM drive.
      
         - Placing the CD-ROM driver above the Stacker driver line
           causes the CD-ROM drive to take the first available drive letter
           BEFORE any Stacker/swapped-host drives.
         - Placing the CD-ROM driver below the Stacker driver line
           causes the CD-ROM drive to take the next available drive letter
           AFTER all the Stacker/swapped-host drives.
           
      A problem may arise if you are using a beta CD-ROM driver named
      OS2CDROM.DMD and dated before 4-22-93.  Some of these drivers
      were true basedevice drivers, which always load before the
      Stacker driver, unless a switch was used with the CD-ROM driver
      (not supported in all the beta drivers).
      
      Make sure you use one of the officially supported CD-ROM device
      drivers and that it is correctly installed (usually through
      initial OS/2 install or Selective Install).
      
      CONFIGURATION IN DOS
      
      You may have to reconfigure your CD-ROM to use a new drive
      letter.  Most CD-ROMs are assigned drive letters by the
      MSCDEX.EXE program through AUTOEXEC.BAT, after Stacker drive
      letters are assigned.  If your drive letter has changed as a
      result of installing Stacker, you may need to reconfigure either
      your Stacker or CD-ROM drive letter.
      
      Which strategy you use will depend upon which version of DOS you
      are running. MS-DOS 6.x, Novell DOS 7, and PC-DOS 6.x with system
      file dates 9-30-93 or later support preloading. If you have one
      of these DOS versions see the section on Preloading Compression.
      If you have another DOS version see the section on Non-
      Preloading.
      
      Configuring the CD-ROM for Preloading Compression
      
      If Stacker is preloading, Setup may detect your CD-ROM. If so,
      Setup will then configure Stacker so that its drive letter
      assignments will begin after the CD-ROM drive. If you add a CD-
      ROM drive later you may have Stacker start assigning drive
      letters at a point after the CD-ROM drive.  For example, if your
      configuration, including the CD-ROM, uses letters C through E,
      you can tell Stacker to start assigning new drive letters with
      drive F.
      
       1.  Go to your Stacker directory.
       2.  Type: ED /I <enter>. This will bring up your STACKER.INI
           file in a text editor.
       3.  Examine the file for a line that reads /BD=X. If so, go to
           that line. If not, press <Enter> to insert a new line.
       4.  Arrow up to the new line and type: (or edit the existing
           line)
           /BD=drive
           where drive is after the last drive letter you wish to
           preserve.  For example, if you want to maintain the identity
           of drives C through E, use /BD=F
       5.  Press CTRL-Z to save the STACKER.INI file.
       6.  Restart your computer
           
      Configuring the CD-ROM for Non-Preloading versions of DOS
      
      If you're not using a preloading version of DOS, you must
      reconfigure the CD-ROM to use the next drive letter after
      Stacker.  For example, if your Stacker configuration uses letters
      C through F, you can reconfigure the CD-ROM as drive G.
      
       1.  Edit your CONFIG.SYS file by typing ED /C  <enter>. The
           lines and sequence should be something like this:
                     DEVICE=C:\STACKER\STACKER.COM
                     DEVICE=C:\STACKER\SSWAP.COM
                     DEVICE=<CDROM DRIVER COMMANDS>
           where <CD-ROM DRIVER COMMANDS>  is your CD-ROM device driver
           and switches.  The CD-ROM driver line is already in your
           CONFIG.SYS file - just make sure that it loads after
           STACKER.COM (and SSWAP.COM if it appears) as shown. Note
           that some CD-ROM drives require a LASTDRIVE statement. That
           line should appear before the Stacker lines. Save the file
           (CTRL-Z) and exit the editor.
       2.  Type C:\STACKER\SWAPMAP <enter> to identify the drive
           letters used at boot time.  For example, if STACKER shows
           that you are using drives C through F, then G is the next
           available drive letter.
       3.  Edit your AUTOEXEC.BAT file by typing ED /A <enter>.  The
           MSCDEX line has this general format:
           MSCDEX /D:name /M:x /V /L:letter /E
       4.  Change letter to the next available drive letter.  If G is
           the next drive letter, the line now looks like this:
           MSCDEX /D:name /M:x /V /L:G /E
                Save the file and restart your computer.
       5.  Verify that the CD-ROM is active by loading a CD and
           checking its contents.  For example, if your CD-ROM is drive
           G, type DIR G: <enter> from DOS, or click on the G drive
           icon.
       6.  Re-setup any applications or programs that have to recognize
           the CD-ROM drive letter automatically.
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      Copyright 1995 Stac Electronics
