Using All 640K on a 286

modified: Sep 12 1997 corrected: 17 Apr 2001


From: kjb=731154@cs.vu.nl (Kees J Bot)
Subject: Full use of 640K on 286
Date: Wed, 10 Sep 1997 10:52:10 +0200

[edited by asw]
original subject was: Re: Documentation for older releases

Originally the boot monitor was configured to be kept in memory waiting
for Minix to return if Minix is running in protected mode.  My
assumption was: protected mode -> at least a 286 -> at least 1M memory
-> enough room for the monitor.

This assumption was wrong, because there are 286's around with only
640K.  In src/kernel/start.c one can find the line:

	if (!protected_mode) mon_return = 0;

For 2.0.1 it is changed to:

	if (!protected_mode || ext_memsize == 0) mon_return = 0;
--
Kees J. Bot, Systems Programmer, Dept. Math&CS, Vrije Universiteit Amsterdam
Minix:       http://www.cs.vu.nl/ftp/minix/   ftp://ftp.cs.vu.nl/pub/minix/
Minix-vmd:   http://www.Minix-vmd.org/        ftp://www.Minix-vmd.org/