                          SHSUCDX Version 1.1a
                      (c) John H. McCoy, May 1996
                   Sam Houston St. Univ., TX 77341-2206

     SHSUCDX is an un-loadable CD-ROM redirector substitute for MSCDEX.
        Version 1.0 supports up to 10 CD drives.  Each drive is single
        sector buffered and the last 10 directory entries are cached.
        Hopefully, the directory function is finally fixed.  Lower case
        characters in directory entries are now converted to upper case.
        LC characters are not valid in ISO9660 directory entries but some
        mastering programs put them in.  This change allows those files to
        be accessed.  The BiblioID can now be read using INT 2F, 1504H.
        The full 37 bytes of the Copyright and Abstract ID fields are now
        returned.  Previously only the first 12 bytes were read.

        Approx 17K of RAM is needed to install SHSUCDX.  The resident size
        for a single drive is less than 11K.  Each additional drive increases
        the resident size by 2500 bytes.  Multiple drivers are supported.
        The driver name, drive letter, drive unit and number of drives from
        each driver can be specified on the command line.

        SHSUCDX does not attempt to read the CD ROM until an access request
        is made.  Thus, the CD drive does not have to be ready when the
        redirector is loaded.  If more than 7 seconds elapse between access
        requests a media check is made.  The buffers and cache are flushed
        and the CD is re-read only if the driver reports a media change.

        When SHSUCDX unloads it marks the drives it used as invalid.

     SHSUCDX has been run with MS-DOS 4, 5, 6 and 7 stand-alone, under
        Windows 3.1, and in a specific DOS window under OS2.

     A CD-ROM driver which supports the CD-ROM extensions must be loaded
        before loading SHSUCDX.  By default, SHSUCDX looks for a driver
        named SHSU-CDN.

     usage:  SHSUCDX [/D:DriverName[,[Drive][,[Unit][,[MaxDrives]]]]]

        DriverName  1 to 8 characters.
        Drive       First drive letter to assign to drives attached to
                       this driver.
        Unit        First drive unit on this driver to be assigned to a
                       drive letter.  (Allowed range 0 to 99)
        MaxDrives   Maximum number of drives on this driver that are to
                       be assigned to drive letters.

        Note:  The drive letter assigned to units of a second driver will
          always be higher than those assigned to the first driver and
          those assigned to a third driver will be higher than those
          assigned to the second.

        example: SHSUCDX

        SHSUCDX finds the first available drive letter and assigns it
        to device unit 0 of the default driver SHSU-CDN.  If there is a
        second and/or third CD drive they are assigned to the next avail-
        able letters in sequence.  Drive letters in use are skipped.  The
        first CD supported by a driver is device unit 0 regardless of its
        SCSI address.

        example: SHSUCDX /D:CD001,F,,1  /D:SHSU-CDN,,1

        SHSUCDX assigns drive F to device unit 0 of the driver CD001.
        Units 1 and 2 of driver SHSU-CDN are then assigned to the next
        available letters.

        example: SHSUCDX /D:CD001,,1,1  /D:CD001,,4,1

        SHSUCDX assigns the first available drive letter to device unit 1
        of the driver CD001 and drive unit 4 to the next.  This allows
        access to non-contiguous drive units without having to support
        un-needed units.

     unload: SHSUCDX [-u|/u]

     The following INT 2F, 15h functions are supported:

        00      Get number of CD-ROM drives
        01      Get CD-ROM drive device list
        02      Get Copyright File ID
        03      Get Abstract File ID
        04      Get Bibliographic File ID
        05      Read VTOC (1st only)
        08      Absolute disk read
        0B      CDROM drive check
        0C      MSCDEX version
        0D      Get CD-ROM drive letters
        0F      Get directory Entry
        10      Send device request


Time permitting, an attempt will be made to fix problems that are reported
  to CSC_JHM@SHSU.EDU.

SHSUCDX is a copyright reserved, free use program.

(c)John H. McCoy, 1994, 1995, 1996 Sam Houston St. Univ., TX 77341-2206