Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!ncar!gatech!bloom-beacon!eru!kth.se!sunic!mcsun!hp4nl!sci.kun.nl!cs.kun.nl!rhialto
From: rhialto@cs.kun.nl (Olaf'Rhialto'Seibert)
Newsgroups: comp.sys.amiga.programmer
Subject: Re: Query: How to destroy WB and Kickstart?
Message-ID: <2924@wn1.sci.kun.nl>
Date: 5 Apr 91 16:37:42 GMT
References: <0by0qu_00WB68MaWZ5@andrew.cmu.edu> <1991Apr2.154016.26566@maths.tcd.ie>
Sender: root@sci.kun.nl
Organization: University of Nijmegen, The Netherlands
Lines: 32

In article <1991Apr2.154016.26566@maths.tcd.ie> ecarroll@maths.tcd.ie (Eddy Carroll) writes:
>In article <0by0qu_00WB68MaWZ5@andrew.cmu.edu> ia0i+@andrew.cmu.edu
>(Indu Tara Agarwal) writes:
>> [ Trying to reset out of Batman on the A1000 hangs the system badly. ]
>>
>>My question is this:  what specific things/events are being sabotaged
>>(probably) so that you have to TURN OFF the machine and restart with Kickstart?
>
>When the Amiga is booting, one of the first things it does is to see if
>ExecBase is intact.

Actually, on a 1000, the first thing that happens is that the BOOT ROM
kicks in at adress 0. It checks first if an intact KickStart is
present, and if not loads it from a KickStart disk. Then it enters
KickStart and does the things you describe.

An interesting thing is, that on entry to the KickStart, the WCS is
write-protected, and at the same time the boot ROM is made invisible.
It will never come back unless you also write-enable the WCS. This can
be done most conveniently by jumping to the RESET instruction just
before the initial KS entry point, which in its turn is indicated in
the second longword in the KS (or somewhere around there). The
interesting thing is that the boot ROM structure is the same as the KS
structure so that on 500s and 2000s the KS could (and does?) work as
boot ROM.

For further info, use a disassembler to look at your boot ROM (at
$f8_0000).

--
Olaf 'Rhialto' Seibert                               rhialto@cs.kun.nl
How can you be so stupid if you're identical to me? -Robert Silverberg