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MyJEMM 1.4
Creator Ross Ridge
Download Download
Filesize 16 kB


Ross Ridge's JEMM emulator for running Privateer, Armada and Strike Commander in Windows 95, Windows 98 or Windows ME.

Archive Contents

  • myjemm.exe
  • vjemm.vxd



By Ross Ridge
Public Domain

@(#) vjemm README 1.4 03/06/09 18:50:51

MyJEMM is a public domain utility for running the game Privateer under
Windows 95, Windows 98 and Windows ME.  It does not work with Windows
NT, Windows 2000 or Windows XP.  MyJEMM works by emulating under
Windows the JEMM memory manager used by Privateer.  It also has only
been tested with Windows 98 and Windows ME, though should in principle
also work under Windows 95.

MyJEMM has preliminary support for Wing Commander: Armada and Strike
Commander, which use a similar version of JEMM to the one that
Privateer uses, but these games have not been fully tested.  MyJEMM is
not needed to run Wing Commander 3, as it uses a completely different
version of JEMM that is compatible with Windows as is.


To install MyJEMM, just copy the files MYJEMM.EXE and JEMM.VXD to
the directory where you installed Privateer.  To uninstall MyJEMM
just delete these files.


Open an MS-DOS window, change directory to where you installed
Privateer and run the "myjemm" command.  To play the Righteous Fire
expansion use the "myjemm r" command.  For one of the other games
MyJEMM supports consult the table below.  You can also create a
shortcut on your desktop or in your start menu to make it possible to
start the game with a mouse click.  Make sure the current working
directory of the shortcut you create points to the directory where you
installed Privateer.

  Game                         Media   Command
  WC: Privateer                either  myjemm
  Righteous Fire               either  myjemm r
  WC: Armada                   disk    myjemm armada.exe
  WC: Armada                   CD      myjemm armadacd.exe
  WC: Armada: Proving Grounds  disk    myjemm pg.exe 
  WC: Aramda: Proving Grounds  CD      myjemm pgcd.exe
  Strike Commander             disk    myjemm s


MyJEMM is essentially alpha quaility software.  It has only been
tested on a couple of systems and may have a number of
incompatibilities.  The JEMM memory manager used by Privateer uses
some very evil tricks to get past the 640k MS-DOS memory limit, as
result it's amazing that it worked as reliabily as it did.  In order
to emulate these tricks under Windows, MyJEMM has to use even more
evil tricks, and it's amazing that it works at all.  Reliability of
the game under Windows unfortunately is not as good as it is under
plain MS-DOS.

The following is a list of some potential problems:

- Only play Privateer in fullscreen mode.  It doesn't work in windowed
  mode, so don't try to switch to it.

- Sound card compatibility is likely to be a problem.  The game has
  only been tested with a real SoundBlaster 16 ISA, a SoundBlaster
  Live and an onboard CMI 8738 chip.  If you have problems you may
  need to disable sound in order to play the game.

- Digital sound effects used by the game are more likely to cause
  problems than the music.  Just disabling sound effects may solve
  sound card compatibility problems.

- Digital sound effects may appear to hang Privateer.  If during
  conversions in game, the portrait of the person speaking continues
  to animate indefinately after the person's speech has finished,
  pressing a mouse button, joystick button or any key on the keyboard
  should allow you to continue.  This can also happen with the speech
  used in the games openning sequence.  Starting Privateer with the
  "myjemm -s" command enables a fix for this problem, but it's not
  recommended unless this problem comes up a lot.

- WDM sound card drivers aren't likely to work.  If possible, switch
  to VxD based drivers.

- Utilities the use evil tricks like MyJEMM often don't work well
  with other utilities that use evil tricks.  Other kinds of software
  that use evil tricks include virus scanners, internet firewalls,
  virtual CD-ROM emulators, and copy-protected Windows games.  If you
  have problems try disabling and/or exiting these kinds of utilities.

- Windows uses more conventional memory than plain MS-DOS does.  You
  may need to free up more conventional memory before you can play
  Privateer under Windows.  If your C:\CONFIG.SYS file doesn't already
  contain an "DEVICE=C:\WINDOWS\EMM386.EXE RAM" line, try adding one.
  Under Windows ME editting your CONFIG.SYS is not an option and you
  may not be able to do anything if you don't have enough free
  conventional memory.

- Since relability is a problem, remember to save your game at every
  opportunity.  Use multiple saves in case one save gets corrupted or


Despite all potential problems with MyJEMM mentioned above, there a
few reasons why you might want to play Privateer under Windows rather
than plain MS-DOS.

- Allows use of USB joysticks.  If the drivers for your USB joystick
  work with MS-DOS games under Windows, then your USB joystick should
  work with Privateer under Windows.

- Allows use of Windows only sound cards.  Many sound cards these days
  aren't compatible with plain MS-DOS.  Unforutnately in practice this
  may not be as big as advantage as it seems, as these kinds of sound
  cards are the most likely to cause compatiblity problems.

- Allows playing Privateer while doing other things on your computer.
  You can do things like ALT-TAB away from the game and read
  Privateer's PDF manual or search the WWW for hints.

I only recommend using MyJEMM if these advantages are relevent to you.
Otherwise it's probably better just play Privateer under plain MS-DOS.


If you have any questions, comments or bug reports about MyJEMM
please e-mail me at  Please remember that
MyJEMM is alpha quality software, that it's public domain (ie. free)
and that I don't get paid to work on or support it.

                                        Ross Ridge

Old Versions