Path: utzoo!attcan!uunet!samsung!shadooby!sharkey!math.lsa.umich.edu!hyc
From: hyc@math.lsa.umich.edu (Howard Chu)
Newsgroups: comp.sys.atari.st
Subject: Re: Software Reset
Message-ID: <10141@stag.math.lsa.umich.edu>
Date: 21 Nov 89 18:57:08 GMT
References: <89112004371539@masnet.uucp> <866@lzaz.ATT.COM>
Sender: news@math.lsa.umich.edu
Reply-To: hyc@math.lsa.umich.edu (Howard Chu)
Organization: University of Michigan Math Dept., Ann Arbor
Lines: 75
UUCP-Path: {mailrus,umix}!um-math!hyc

Just a couple comments on this...

In article <866@lzaz.ATT.COM> hcj@lzaz.ATT.COM (HC Johnson) writes:
%In article <89112004371539@masnet.uucp>, tellabs.canada@canremote.uucp (TELLABS CANADA) writes:
%> Required with the utmost urgency is a (C, Modula2 <-preffered) routine
%> to perform a rather cold reset (re-load auto folder etc.) in pre tos1.4
%> and tos1.4 machines. I'd be eternally grateful.
%>  
%
%
%Howard C. Johnson
%ATT Bell Labs
%att!lzaz!hcj
%hcj@lzaz.att.com
%
%
%Subject: Simple program to reboot an Atari ST
%Message-ID: <152@decvax.UUCP>
%Date: 20 Sep 87 19:04:56 GMT
%Reply-To: minow@decvax.UUCP (Martin Minow)
%Distribution: world
%Organization: Digital Eq. Corp. - Merrimack NH.
%Lines: 40
%
%#if 0
%This illustrates how to emulate the white button (warmstart) or
%power-switch on an Atari.  It *should* be compatible with the new roms.
%Normally, you would add the guts to an existing program.
%
%Martin Minow
%decvax!minow
%#endif
%
%/*
% * Reboot an Atari ST.  This program is in the public-domain.
% * Martin Minow, Arlington MA 02174, USA.
% */
%
%#include <osbind.h>
%#include <linea.h>
%
%#define OS_memvalid	(*((long *) 0x420L))
%#define	OS_memval2	(*((long *) 0x43AL))
%#define OS_resvalid	(*((long *) 0x426L))
%#define OS_restart	(*((int(*)()) 0xFC0000L))
%
%main()
%{
%	int		hardboot;
%	long		oldstack;
%
%	hidemouse();
%	Cconws("\033EX or x to hardboot, anything else to softboot: ");
%	hardboot = Cconin() & 0xFF;
%	oldstack = Super(0L);			/* Get into super mode	*/
%	if (hardboot == 'X'
%	 || hardboot == 'x') {
%	    OS_memvalid = 0L;			/* Invalidate the OS	*/
%	    OS_memval2  = 0L;			/* "up and running"	*/
%	    OS_resvalid = 0L;			/* flags.		*/
%	}	    	
%	OS_restart();				/* Imitate system reset	*/
%	Super(oldstack);			/* We never get here	*/
%}

Lessee if I can get in before kbad does.  }-)  You shouldn't assume that
the ROM lives at 0xFC0000, 'cause it can move around on you.
A better way would have been to declare a pointer to the reset function,
and set that the 0x42a, the resvector system variable. Then jump
thru the pointer.

A question - why doesn't anyone just use the 68000 RESET instruction?
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