 
	   =================================================
	              Comments on "Device Drivers"
	   =================================================



1) Installation of Real Mode CD drivers allows the CDrom to function when
the protected mode of the GUI interface is not available.  This is usually
required when you desire access to your CDrom device when booting to MSDOS
with a floppy disk.  This condition exists when Windows fails to boot into
the GUI which will preclude access to the CDrom drive.  Although CDrom
manufacturers accompany Cdrom drives with a floppy disk with the specific
drivers to use, they may or may not be available now.  In an attempt to
provide access to the Cdrom when the manufacturers driver file is not
available the Memphis EBD contains a generic Cdrom driver file that could
work on your machine.  To try the provided Cdrom driver to gain access to
the CDrom drive, complete the following directions.

	The following lines should be added to 
        "Config.sys" and "Autoexec.bat": that are on the a:\ drive.

CONFIG.SYS file add  Device=ATAPI2CD.SYS /D:mscd0001 /i:0

AUTOEXEC.BAT file add MSCDEX.EXE /D:mscd0001 /V /M:12

2) Options for the device driver, ATAPI2CD.SYS

   a) /D:<device_name>

      * Device driver needs to have a <device_name> listed on the command
        line MSCDEX following the /D: switch. MSCDEX uses this 
        parameter to locate device driver. Names used must match those
        used for the /D:<device_name> parameters for each device entry 
        in "AUTOEXEC.BAT".

      * The installation software specifies the device name as "mscd000",
        which appears in "CONFIG.SYS" as well as "AUTOEXEC.BAT".

   b) /I:n

     * This option is related to "Media Change Command" and "Illegal
       disc change", specified in MSCDEX.  It is required
       to notify the system that a disc has been changed so that this
       information can be used in various ways, eg. to initialise
       a buffer memory with directory information, etc.

       However, there are several ways of treating this
       information so we have added an option "/i:n" to allow the
       user to choose an appropriate setting.

     * No option at all.
       If the drive tries to access a CD-ROM when there is no disc in the
       drive, it will return "illegal media change". This in turn will be
       expressed as "Not ready error reading.." and displayed on the screen.

       This will not be cleared straight away, even after a CD-ROM disc is
       inserted, but second retry will clear this message.

     * n=0
         Our installation software will set this option, because we feel
         this is more appropriate than default setting which is specified by
         MSCDEX specification.

         Note : Some major SCSI products vendors have this setting as
	      their default setting.

     * n=1
         The driver will keep returning "Media Change Status" until
         "Media Change Command (A command which checks if the media
         has been changed or not) is executed.  During this stage, the system
         will keep displaying the following message on the screen, even
         after media has been loaded.

         Not ready error reading drive X:
         Abort, Retry, Ignore?
         (* X: Drive letter of CD-ROM drive)

     * /i .... Same as "/i:1"
     
   c) /p:XXX                                 
        When user specifies one of the following address, ie. /p:xxx, 
        the device driver selects the only specified port address.

         Primary         /p:1F0
         Secondary       /p:170 
         Tertiary        /p:1E8
         Quaternary      /p:168
         F.D. board      /p:160 (Futuredomain)

      However, the F.D. board's address(160H) and Quaternary's 
      address(168H) can not be used together.

      Without specifying this option, the device driver can select the 
      drive by "auto-detect" mode in any of the Primary, Secondary, 
      Tertiary, Quaternary, and F.D. board.

    d) /g
        When connecting a Sony drive as master through the ATA interface with
        a Green PC, and if no other slave device is connected, the device
        driver responds with "Drive not Ready" to any command from the host
        computer after the host computer enters suspend mode.
        Option "/g" is added to solve this problem.

    e) /h
         This option cancels Enhanced CD support. 

       
3) Option for MSCDEX.EXE

   a) /D:<device_name>

      * Device driver needs to have a <device_name> listed on the command
         line to MSCDEX following the /D: switch. MSCDEX uses this parameter
         to locate the device driver. Names used must match those used for the
         /D:<device_name> parameters for each device entry in "CONFIG.SYS".

      * The installation software specifies the device name as "mscd0001",
         which appear in "CONFIG.SYS" as well as "AUTOEXEC.BAT".

    b) /M:<value>
         This option switch determines how many sector buffers MSCDEX 
         allocates when it installs itself.  The larger the value, the
         more sector cache entries are available and the less MSCDEX will
         have to read directly from the CD-ROM drive. Please increase this
         value if you require better performance, but bear in mind that it
         will use up system memory space.  It is also possible to reduce the
         value, but a minimum of 4-5 is recommended.  If this value is too
         small, the drive will reread more often which deteriorates
         its performance.

    c) /V
         This is "verbose switch". /V asks MSCDEX to print additional
         information about memory usage during initialisation. We recommend
         setting this switch.

    d)  /E
          This is an additional switch which tells MSCDEX to use expanded
          memory if it is available.

    e)  /L:<drive letter>
          This option is for software that requires a specific
          drive letter so that the application software can interface with
          CD-ROM drive without problems.  Because "SETUP.EXE" does not set
          this switch, you will have to edit your AUTOEXEC.BAT file if this
          switch is needed.  For example, to assign CD-ROM drives starting
          at the letter L:, you would need to add the switch "L",
          as you can see below:

	 MSCDEX /D:MSCD0001 /L:L

     f) /K
          The /K switch causes MSCDEX to look for a Supplementary Volume
          Descriptor that identifies a shift-JIS Kanji volume for Japanese.

     g) /S
          The /S switch tells MSCDEX to patch MS-DOS to allow sharing of
          CD-ROM drives on MS-NET based servers.
