      -----------------------------------------------------------------
      STACKER NOTE                                         STACKER NOTE
                         MEMORY MANAGEMENT & STACKER
                      (Applies to Stacker Versions 2.x, 3.x, 4.0)
      STAC FAX  4105 (05-10-1994)
      -----------------------------------------------------------------
                                      
      BACKGROUND
      
      The goal of memory management is to achieve the maximum
      conventional memory (the area below 640K). You may move device
      drivers such as Stacker to areas of memory called Upper Memory
      Blocks (UMB's) in order to maximize conventional memory. The
      manner in which you move Stacker into the UMB's will depend upon
      the configuration of your system.  Factors include the type of
      CPU (ex. 80386), the version of DOS, the version of Stacker, and
      which memory manager you have.  CPU's prior to the 80286 do not
      support memory management.  Whatever your configuration, the
      Stacker line in the CONFIG.SYS file must be manipulated by a
      properly configured memory manager in order to load Stacker high.
      
      NOTE: IF YOU ARE USING THE STACKER XT-8 CO-PROCESSOR HARDWARE,
      SEE STAC FAX 2102.
      
      SOLUTIONS
      
         - Use a commercial memory manager that automates the memory
           management process, or
         - Use the memory managers incorporated into DOS to manually
           load Stacker high, or
         - Use the proper expanded memory manager software and hardware
           for 80286 processors.
           
      USE OF COMMERCIAL MEMORY MANAGERS
      
         1. Commercial memory managers such as QEMM, 386MAX, Netroom,
            and MS-DOS 6.0/6.2's Memmaker automate the complexity of
            memory management.  You may install these products on a
            Stacker drive and use them in accordance with the
            manufacturer's instructions to load Stacker (and other)
            device drivers high.
         2. DOS versions prior to 5.0 do not include their own memory
            managers, and a commercial memory manager is required to
            load device drivers such as Stacker high.
           
      MANUAL USE OF DOS MEMORY MANAGERS
      
      Note: These procedures assume an 80386 or better processor.
      
      DOS versions 5.x and 6.x include memory managers called HIMEM.SYS
      and EMM386.EXE that may be used to manually load Stacker high.
      (As noted above, MS-DOS 6.0/6.2 also includes the automated
      memory manager, Memmaker.)
      
       1.  The Stacker device driver may be loaded into the UMB's if
           the system is configured properly and if there is a UMB
           large enough to accommodate it. Freeing up UMB's that are
           large enough may require much trial and error. You may  have
           to experiment with the order in which device drivers are
           loaded. If you attempt to load the Stacker driver into the
           UMB's and they are not large enough, the driver will simply
           load into the lower 640k of conventional memory. Complete
           details on using DOS's memory managers are included in your
           DOS documentation.
       2.  The CONFIG.SYS file must contain the following statements
           (in this order):
              DEVICE=C:\<dir>\HIMEM.SYS
              DEVICE=C:\<dir>\EMM386.EXE <switches>
              DOS=UMB
           where <dir> is DOS or WINDOWS and <switches> are explained
           later.
       3.  Load the Stacker device driver HIGH by changing the syntax
           from  DEVICE=  to   DEVICEHIGH= in CONFIG.SYS:
           
           For Stacker versions 3.0 and earlier, or DOS version 5.x
           with any Stacker version:
      
              DEVICE=C:\STACKER\STACKER.COM  C:\STACVOL.DSK  becomes
              DEVICEHIGH=C:\STACKER\STACKER.COM  C:\STACVOL.DSK
           Notes: (1) For Stacker versions prior to 3.0, you may have
           to copy the files HIMEM.SYS and EMM386.EXE to the
           uncompressed boot drive to ensure they are available during
           startup. Type STACKER at the DOS prompt. The drive that
           swaps with drive C: is the uncompressed boot drive. (2)
           Stacker's SSWAP program is not memory-resident.  Therefore,
           it is not necessary to load its device driver high. (3) The
           Stacvol file name will not appear on the STACKER.COM line
           with Stacker 4.0. 

           For Stacker version 3.1 and later and most versions of DOS 6
           or later
              DEVICE=C:\STACKER\STACHIGH.SYS  becomes
              DEVICEHIGH=C:\STACKER\STACHIGH.SYS
           Note that with Stacker 4.0, the DEVICEHIGH statement is
           automatically inserted.
       4.  EMM386.EXE switches (parameters) tell EMM386 to perform a
           variety of functions like opening the Upper Memory Area for
           device drivers and other memory-resident programs, or to
           create Expanded (EMS) memory for applications.  The switches
           you choose will depend on your applications and the type of
           memory they require.
            -If no EMS memory is required, use the NOEMS parameter.
             This will provide access to the UMBs and create 64K more
             usable space than the RAM parameter.  No EMS services
             will be provided.  For example:
              DEVICE=C:\DOS\EMM386.EXE  NOEMS
            -If some applications use EMS memory, use the RAM
             parameter.  This will provide access to the UMBs and
             create a 64k EMS page frame.  For example:
              DEVICE=C:\DOS\EMM386.EXE RAM
            -For further information concerning the EMM386 switches,
             see your DOS documentation.
       5.  To see if the Stacker device driver was successfully loaded
           into the UMB's, use the DOS MEM command. Type: MEM /C  to
           view the memory map.
           
      USE OF EXPANDED MEMORY MANAGERS WITH 80286 PROCESSORS
      
       1.  Loading Stacker high on an 80286 computer requires the
           appropriate memory management software such as QRAM or
           MOVE'EM, and hardware support for the Expanded Memory
           Specification (EMS) 4.0. An expansion board usually provides
           hardware support . Refer to the manufacturer's instructions
           for proper use.
      -----------------------------------------------------------------
      Copyright 1994 Stac Electronics
