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From: fisher@sc2a.unige.ch (Markus Fischer)
Newsgroups: comp.sys.ibm.pc
Subject: Re: HELP!!
Summary: debug inline assembly code for **boot.com
Keywords: reboot
Message-ID: <81@sc2a.unige.ch>
Date: 5 Jun 89 04:31:04 GMT
References: <8905231642.AA09814@cunixa.cc.columbia.edu>
Organization: University of Geneva, Switzerland
Lines: 53

In article <8905231642.AA09814@cunixa.cc.columbia.edu>, cmm1@CUNIXA.CC.COLUMBIA.EDU (Christopher M Mauritz) writes:
> Does anyone out there have a small program that will cause a pc to reboot?

I do !

This question certainly has much better answers, but here is one that works for
my IBM AT 2.  The idea comes from the implementation of  the <Alt-Ctrl-Del> key
in some  obscure keyboard  driver from  DOS 2.11...  i.e. jumping  to the right
address.  I have heard say there is an interrupt, you might want to  check that
also...

Cut these two files as `*.deb' or the like, then feed them to DEBUG, as:
prompt> DEBUG < BOOT.DEB
They simply  say `a'ssemble (follows the code... an empty line to stop), `n'ame
the file as (string), `rcx' - new value  for CX,  containing the  length of the
file, `n' being the length, `w'rite the file, and `q'uit !

--- COLDBOOT.DEB ----------------------------------------------
a
         JMP F000:FFF0                          

n COLDBOOT.COM
rcx
5
w
q
--- WARMBOOT.DEB ----------------------------------------------
a
           MOV AX,0040                            
           MOV ES,AX                              
           ES:                                    
           MOV WORD PTR [0072],1234               
           JMP F000:FFF0                          

n WARMBOOT.COM
rcx
11
w
q
---------------------------------------------------------------

Voila`!   The only  difference between  the two  is that the `warm'boot doesn't
count the memory again.

Hope this is useful !

Markus Fischer                -|--|--|--|--|--|--I   Department of Anthropology
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black (#) to kill ! --|--|-(#)(_)(_)(_)(#)(#)(_)(_)  fisher@sc2a.unige.ch
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