FILE XONXOFF.HLP          SERIAL PRINTER DRIVER                 September 1991

XONXOFF.COM is a tiny public domain serial printer driver for MS-DOS computers,
written by Frank Whaley in 1989 and found by Joe Doupnik in the mirror/printer
directory on wuarchive.wustl.edu.

MS-DOS allows you to define a COM port as a printer device using the MODE
command, for use with a serial printer, for example:

  MODE COM1:9600,N,8,1,P
  MODE LPT1:=COM1

However, MS-DOS does not provide flow control between itself and a serial
printer.  MS-DOS Kermit uses standard DOS calls for printer operations (print
screen, transparent print, autoprint, etc).  A common complaint is that these
print operations do not work well with serial printers -- characters are lost
or garbled, etc.

XONXOFF.COM provides software (Xon/Xoff) flow control for serial printers.  It
works only for COM1 only.  It installs itself as a terminate-and-stay-resident
(TSR) program, intercepts DOS interrupt 17H, leaves the port baud rate and
other parameters as found (so you must set them with the MODE command), and
contains no provisions for de-installation.

Run it from your AUTOEXEC.BAT file after giving the necessary MODE commands,
for example:

  MODE COM1:9600,N,8,1,P
  MODE LPT1:=COM1
  C:\KERMIT\UTILS\XONXOFF

(End of XONXOFF.HLP)