This text written by Thomas Raukamp.

Since the development of the Atari 8-bit line of computers in 1979, users
wanted better text displays than the default 40x24.  There have been some
attempts to satisfy this need, like the Austin-Franklin board or the ACE-80
and ACE-80XL cartridges.  For more information about these modifications read
The Atari 8-bit Hardware Upgrade FAQ from David A. Paterson.

The Atari XEP80 Interface Module is Atari's entry to the 80 column field.  It
lets a XL, XE, 400 or 800 computer system display a full 80 columns across
your monitor screen.  The XEP80 provides a 256-character wide by 25-line
display window.  Up to 80 characters are displayed horizontally at once, and
you can scroll horizontally all the way to the 256th character, depending on
the application you're running.  The XEP80 is connected to your system via a
joystick port.

The XEP80 Module interprets commands from the computer for screen display or
output to a printer.  The module is supplied with an industry-standard 8-bit
parallel port so you can connect a parallel printer to your Atari 8-bit (I
even use a HP LaserJet IV on my 130XE ;) ).

All programs that use the standard screen call (E:) should be compatible with
the XEP80 Module.  The software provided by Atari supports a 320x200 graphics
mode - this mode only support direct bit images.  Note that you can't use all
of the standard graphic capabilities of the Atari anymore.

Although Atari recommends a monochrome monitor for usage with the XEP80, it
runs fine with any type of composite monitor.  The output looks great on my
Commodore 1084 for example.

Along with the module comes a software-package containing an AUTORUN.SYS file,
which is the XEP80 handler.  If you want to use the module with an application
that is compatible with the XEP80, which has its own AUTORUN.SYS file, you
can append the application's AUTORUN.SYS on the module's AUTORUN.SYS.
***********************
The key engineer/designer of the XEP80 was Jose Valdes at Atari.
Lane Winner was software developer for the XEP80 at Atari.

Editors for the XEP80:
 - AtariWriter 80 by Atari
 - TurboWord by MicroMiser
 - emacs subset by Stan Lackey
 - MAE and its previous standalone editor ED

XEP80 P: Parallel port:
   13                         1
     o o o o o o o o o o o o o
      o o o o o o o o o o o o
    25                       14
    1. Strobe
  2-9. Parallel Data
   10. Not Used
   11. Busy
12-17. Not Used
18-25. Ground