🚀 go-pugleaf

From article <1991Apr15.160333.8107@msuinfo.cl.msu.edu>, by mackay@eecae.ee.msu.edu (James F. MacKay):
> Can someone explain to me how to write a program that is capable
> of running normally in protected mode, but can switch into real
> mode for DOS calls?  MS C and/or ASM preferred.
> 
  Switching from protected to real mode in 286 processors is not
trivial, but is possible.  I recomment obtaining the latest
INTER???.ZIP from SIMTEL20 at PD1:<MSDOS.INFO>.  This document shows
the location of the "reset code" in the BIOS and the useful code
values.  This code is checked by the BIOS each time the system is
booted (reset or powerup).  If this word is set to 1234H then the
POST stuff is not executed and control is given directly to DOS.
This is important for 286 protected to real mode switching since the
only way to kick the 286 out of protected mode it to reset it.
This, of course, requires resetting the entire machine.  Using
this special code, you can somewhat quickly set the 286 to real
mode.

  Shane();

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From the keyboard of:			     email: sdawalt@cs.wright.edu
	Shane A. Dawalt
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