@@MENU
   Configure Switches:
        You may reconfigure the following areas of the 386|DOS-Extender:
            1) Swap files
            2) Conventional memory
            3) Extended memory
            4) Interrupt
            5) System

   Reset Switches:
        If you have made changes to the 386|DOS-Extender switches, you can
        reset these switches to their original settings by selecting Reset
        Switches from the Main menu.

   Exit:
        1) End:    Save current switch settings that you have changed and 
                   exit the program.

        2) Quit:   Exit program without saving any changes. 

        3) Resume: Return to the Main menu.

   ^x70ESC^n key will cancel you out of an option without saving the changes
   you have made.
@@PRIVEC


  The IBM BIOS uses INT 5 as the print screen function call.  In protected
  mode, INT 5 is treated as a BOUND exception by 386|DOS-Extender.

  By default, 386|DOS-Extender makes the BIOS print screen function 
  available in protected mode by issuing an INT 80h.  The ^x70privec^n switch
  selects a different interrupt vector, in the range 30h - FFh.  The switch
  ^x70privec 5^n can be used to tell 386|DOS-Extender not to make the BIOS
  print screen function available in protected mode.

  NOTE:  We recommend that you do not set ^x70privec^n.
@@MINREAL


  The ^x70minreal^n and ^x70maxreal^n switches are used to control how much
  conventional memory is left free by 386|DOS-Extender.  By default,
  386|DOS-Extender allocates all the available conventional memory for
  use by AutoCAD.
 
  If you are using an ADI display driver that requires conventional memory
  from AutoCAD, you must make sure that 386|DOS-Extender leaves sufficient
  conventional memory free.  The ^x70minreal^n switch specifies the minimum
  amount of conventional memory to leave free; 386|DOS-Extender refuses to
  run the program if it cannot leave at least this amount of memory free.
  The ^x70maxreal^n switch specifies the maximum amount of conventional memory
  to leave free.  386|DOS-Extender guarantees that at least minreal memory
  is left free and that as much as possible, up to maxreal memory, is left
  free.
 
  Both ^x70minreal^n and ^x70maxreal^n switches take a number as an argument.
  The number specifies memory size in units of 16-byte paragraphs
  (the standard unit of memory allocation under MS-DOS).  The number must
  be less than or equal to 65535 (FFFFh).  By default, 386|DOS-Extender
  sets both ^x70minreal^n and ^x70maxreal^n to zero.
 
  You can choose to set only the ^x70maxreal^n switch, in which case
  386|DOS-Extender frees as much conventional memory as possible, up to 
  the ^x70maxreal^n amount, but AutoCAD can still run with less than that
  amount.  Alternatively, if you set both the ^x70minreal^n and ^x70maxreal^n
  switches, you'll know when there is not sufficient conventional memory
  for the ADI driver because AutoCAD will not run.
 
  NOTE:  We recommend that you do not set ^x70minreal^n and ^x70maxreal^n unless
         you need conventional memory beyond what is needed to load your
         TSR and real-mode ADI applications prior to executing AutoCAD.
@@EXTLOW
 

  The ^x70extlow^n and ^x70exthigh^n switches are used to limit the amount of 
  extended memory (memory above one megabyte) that 386|DOS-Extender 
  allows AutoCAD to use.  By default, all extended memory that is not 
  allocated to other programs is available for use by AutoCAD.  Other 
  programs which may have allocated extended memory include RAM disk 
  programs, disk cache programs, and EMS simulators.
 
  Both the ^x70extlow^n and ^x70exthigh^n switches take a number as an argument. 
  The number specifies a physical memory address in extended memory. 
  By default, 386|DOS-Extender sets ^x70extlow^n to 100000h (one megabyte) 
  and ^x70exthigh^n to FFFFFFFFh (four gigabytes).  386|DOS-Extender uses only 
  extended memory above the address specified with the ^x70extlow^n switch, or 
  memory used by other programs, whichever is higher.  Similarly, it uses 
  only extended memory below the address specified with the ^x70exthigh^n switch,
  or memory used by other programs, whichever is lower.
 
  Normally, it is not necessary to use the ^x70extlow^n or ^x70exthigh^n switches. 
  However, if your system has a program installed that uses extended 
  memory and does not use the following standards, it may be necessary to
  use one or both of these switches to prevent 386|DOS-Extender from 
  allocating extended memory used by the installed program.
 
  *  The VDISK or RAMDRIVE standards for allocating memory from one 
     megabyte up, or:
 
  * The INT 15h function 88h BIOS call for allocating extended memory 
    from the top of memory down.

  NOTE:  We recommend that you do not set ^x70extlow^n and ^x70exthigh^n unless
         necessary so that AutoCAD may use as much extended memory as
         possible for optimal speed.  By not doing so, ^x70extlow^n defaults 
         to 100000h and ^x70exthigh^n to FFFFFFFFh.
@@INTMAP


  386|DOS-Extender needs to know which interrupt vectors are used for
  hardware interrupts.  Normally, if the default MS-DOS interrupts are
  not used, 386|DOS-Extender can automatically determine this condition.
  However, if there is a compatibility problem, due to another program
  relocating hardware interrupts IRQ0-7 from their default DOS interrupt
  vectors of 08h-0Fh, the ^x70intmap^n switch can be used to tell 386|DOS-
  Extender where hardware interrupts IRQ0-7 are mapped.
@@VDISK


  The ^x70vdisk^n switch is a workaround for compatibility problems with other 
  programs which do not correctly follow the VDISK standard for allocating 
  extended memory.
 
  If 386|DOS-Extender refuses to run AutoCAD because of inconsistent VDISK
  allocation signatures, this switch can be used to force 386|DOS-Extender
  to run AutoCAD.  The larger of the two allocation marks present will be 
  used.
 
  Before using this switch, you should check the allocation sizes printed 
  out with the error message when 386|DOS-Extender refuses to run AutoCAD.
  If the larger of the two numbers printed out does not seem reasonable, 
  it will be necessary to calculate how much extended memory is in use by 
  other programs and to use the ^x70extlow^n switch to inform 386|DOS-Extender
  of the correct value.
@@A20


  The ^x70a20^n switch is used to control how address line 20 is enabled or 
  disabled.  80386 systems that conform to the IBM PC/AT standard have 
  hardware either to allow full 32-bit addressing ("enable ^x70a20^n") or to 
  truncate addresses to 20 bits ("disable ^x70a20^n"). When executing in real 
  mode, ^x70a20^n is normally disabled for compatibility with programs that 
  take advantage of the address space wrap-around occurring at one 
  megabyte on 8088/8086 systems.  Very few programs rely on this behavior; 
  the most common example is copy protection programs.
 
  By default, 386|DOS-Extender enables ^x70a20^n before starting AutoCAD, and 
  restores the original ^x70a20^n setting when AutoCAD terminates.  The ^x70a20^n 
  switch can be used to force 386|DOS-Extender to disable ^x70a20^n each time 
  the 80386 is switched to real mode, and to re-enable ^x70a20^n each time the 
  80386 is switched to protected mode.  This can be important if, 
  for example, a software driver, which can gain control at any time via 
  a hardware interrupt, and which relies on one-megabyte addressing 
  wrap-around, is installed on your machine.
 
  There is a penalty associated with the ^x70a20^n switch. Depending on the 
  hardware in your system, it can take several milliseconds to enable 
  or disable ^x70a20^n.  Thus, using the ^x70a20^n switch slows down the switch to 
  80386 real mode, then back to protected mode, that occurs whenever there 
  is a hardware interrupt or a DOS or BIOS function call.
@@SAVEREGS

  The ^x70saveregs^n switch forces 386|DOS-Extender to preserve the high 16 bits
  of general registers across switches to real mode initiated by software
  interrupts.

  Using the ^x70saveregs^n switch protects an application program from real-mode
  code that uses but does not restore the high 16 bits of the general
  registers.  This register saving operation is always performed by default
  for INT 21h and INT 15h.

  This switch has no effect on mode switches initiated by system calls
  250Eh, 2510h, or 2511h.
@@XT


  The ^x70xt^n switch is used to inform 386|DOS-Extender that it is executing 
  on an IBM-compatible PC or PC/XT with a 386 board, such as the Intel 
  Inboard/PC, installed.  386|DOS-Extender normally detects such 
  configurations automatically, but it may not be able to detect systems 
  which do not have the IBM-standard system ID byte in the BIOS.
  If 386|DOS-Extender does not correctly detect a PC environment, this 
  switch can be used to allow AutoCAD to execute successfully.
@@NOPCD


  The ^x70nopcd^n switch turns off the assertion of the PCD (Page Cache Disable)
  bits for the Weitek or Cyrix memory-mapped coprocessors on 486 or later
  PCs.  By default the PCD bits on 486s or higher are asserted.  On Compaq
  machines, the PCD bits are NOT asserted to work around a bug on Compaq
  486/33L machines.  This switch can be used to turn off PCD bits on any
  486 or later PC.
@@ERRATA17


  80386 chip steps B1 and earlier have two chip errata (known as
  "erratum 17" and "erratum 21") that occur only with protected mode
  programs that use the 80387 floating point coprocessor.  Both errata
  cause the 386 to stop processing instructions when an 80387 instruction
  is executed under certain conditions and the program appears to hang.
  Neither erratum exists in any 386SX chip or in 386 chip step D0
  (released in the second quarter of 1988) and later.

  The ^x70errata17^n switch installs a software workaround for erratum 17,
  but leaves paging enabled (there is no viable software workaround for
  erratum 21 with paging enabled).  The ^x70errata17^n switch is only needed
  if 386|VMM is used, and is only effective if a hardware workaround for
  erratum 21 is in place (preventing erratum 17 does no good if erratum 21
  can still occur).  Either use chip step D0 or later of the 386 chip, or
  get a hardware piggyback board with a workaround for erratum 21 from
  Intel or other hardware vendors.  Some PC motherboards have a hardware
  workaround for erratum 21 designed in; for example, all Compaq 386/20
  PCs have a hardware workaround.
@@SWAPNAME


  The ^x70swapname^n switch specifies the swap file name.  If this switch is not
  used, as is the default case with AutoCAD, then a DOS temporary (unique)
  file name is used.  If the file name specified with the ^x70swapname^n switch
  is already present on the swap device, 386|VMM refuses to run.
@@SWAPDIR


  The ^x70swapdir^n switch specifies the device and directory in which to place
  the page swap file.  The default location for the swap file is the root
  directory of the device from which the application program was loaded,
  unless the ^x70swapdefdisk^n switch is used, which is how AutoCAD is shipped
  to you.  In that case the default location is the root directory of your
  current disk.  

  This switch is useful for placing the swap file on a device which has
  sufficient free space to allow the swap file to grow as needed.
 
  The directory name specified with this switch must not end with a "\" 
  character, as 386|VMM appends a "\" before adding the name of the swap 
  file.  The swap file is created with a unique file name (using the DOS 
  Create Temporary File system call).
@@SWAPDEFDISK


  The ^x70swapdefdisk^n switch selects the current default disk drive for the
  swap file (otherwise the default is the disk on which the application is
  located).  One function of this switch is to avoid performance degradation
  from paging over a network.
@@MINSWFSIZE


  The ^x70minswfsize^n switch creates a minimum-sized swap file.  The size is 
  specified in bytes.  This switch guarantees that a minimum amount of 
  swap space is available at startup.  The swap file can then grow
  beyond the minimum as required by the program.

  NOTE:  We recommend setting ^x70minswfsize^n to ^x70400000^n.
@@MAXSWFSIZE


  The ^x70maxswfize^n switch is used to limit the maximum disk space that is 
  allocated to the swap file.  It specifies a size, in bytes, beyond which 
  the swap file is never increased.  If this switch is not used, the only 
  upper bound on swap file size is the amount of free space available on 
  the disk.

@@NOPGEXP


  The ^x70nopgexp^n switch forces 386|VMM not to page out of the .EXP file.
  When used, 386|DOS-Extender reads the entire program into memory at load
  time and places all swapped out pages (including code pages) in the swap
  file.  This can be useful if the application is loaded from the network
  server and paging over the network causes performance degradation.
@@VSCAN


  The default setting in AutoCAD for the ^x70vscan^n switch is 20000 milliseconds
  or 20 seconds.  This is how often the 386|DOS-extender scans the page
  tables to see if swapping will be required.  This setting can be adjusted
  to optimize the performance of some digitizers with AutoCAD.  

  The frequency of the page table scans is only important on systems where
  there is moderate to heavy swapping activity.  The more scans per second
  that are conducted allow the VMM driver to make a better choice of which
  pages to swap out.

  On certain polling digitizers, frequent scans of the page table make the 
  digitizer skip or miss a sample.  If you decrease the number of scans per
  second, by setting ^x70vscan^n to a higher number, digitizer performance is
  markedly improved.  If you have a polling digitizer and are running on a 
  system with a lot of memory, keep ^x70vscan^n at 20,000 (20 seconds) or higher.


  If your digitizer is not a polling type, set ^x70vscan^n to a lower number,
  for example, 4000 milliseconds (4 seconds).

  You may want to test different ^x70vscan^n parameters to achieve an optimal
  balance between digitizer performance and overall AutoCAD performance.
@@DEMANDLOAD

  The ^x70demandload^n switch causes AutoCAD 386 not to initially load into
  memory; instead it is paged in as needed.  This reduces load time and
  guarantees that program pages are not read into memory until needed.
  This may actually increase overall program run times on machines with
  a lot of physical memory, due to the overhead of reading the program in
  one 4K page at a time instead of all at once.

  This switch only applies to "acad.exe", it makes no difference on
  ADI or ADS programs.
@@MAXVCPIMEM

  The ^x70maxvcpimem^n switch allows you to configure the DOS-Extender's
  acquisition of VCPI-style expanded memory.  This allows you to inhibit 
  AutoCAD's desire to acquire all the available expanded memory from a VCPI
  manager such as QEMM, 386MAX, or CEMM.

  You may need to use this switch in order to ensure that an ADI display
  list driver obtains a specified amount of expanded memory.  For example, 
  on a 4MB system, if you have an ADI driver that requires 1 MB of 
  expanded memory:

  1.  Allocate all the extended memory to the VCPI-compatible 386 memory
      manager.  This converts all the extended memory to simulated expanded
      memory.

  2.  Configure the AutoCAD 386 executable to acquire a maximum of 3MB of
      VCPI memory by setting the ^x70maxvcpimem^n switch to 3,072,000.


  Now you can run AutoCAD 386 and allow the ADI driver to acquire 1MB of
  memory to store its display list.

  By default AutoCAD does not use the ^x70maxvcpimem^n switch.
  If the ^x70maxvcpimem^n switch is not used, 386|DOS-Extender will allocate all
  available EMS memory.
@@MAXBLKXMS

  The ^x70maxblkxms^n switch defines the maximum size, in bytes, of an individual
  XMS block (default = 4 GB).  XMS memory, unlike direct extended memory and
  VCPI memory, cannot be released until after the program terminates.  This
  switch can be used to cause 386|DOS-Extender to allocate XMS memory in 
  smaller chunks, leaving some XMS memory free if the application doesn't
  need it all.
@@MAXXMSMEM

  XMS memory refers to memory allocated through the XMS (eXtended Memory
  Specification) interface, the Microsoft standard for allocation of
  memory above one MB.  The XMS interface is usually provided by installing
  a device driver called HIMEM.SYS.

  The ^x70maxxmsmem^n switch defines the maximum number of bytes of XMS memory to
  allocate (default = 4 GB).
@@MAXEXTMEM

  The ^x70maxextmem^n switch defines the maximum number of bytes of direct
  extended memory to allocate (default = 4 GB).

  This switch can be used instead of ^x70extlow^n and ^x70exthigh^n as a
  means of controlling extended memory usage.
@@NOSPCL

  The ^x70nospcl^n switch disables the automatic use of special memory, such
  as the built-in memory mapped above 14 MB on Compaq 386 machines.  By
  default, 386|DOS-Extender attempts to use such memory if it is not
  allocated to another program.  This switch instructs 386|DOS-Extender
  not to check for such memory.  Normally, it is not necessary to use this
  switch.
@@VSLEN

  The ^x70vslen^n switch specifies the maximum amount of linear address
  space to process on each ^x70vscan^n scan.  One might vary this parameter
  to improve digitizer performance by doing less work on each ^x70vscan^n.
  ^x70vslen^n has no effect on Interrupt mode digitizers. 
@@LFU

  The ^x70lfu^n switch sets the page replacement policy to Least Frequently
  Used.  This is the default page replacement policy.

  The ^x70nur^n switch sets the page replacement policy to Not Used Recently.
@ 
