Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!cbmvax!cbmehq!babylon!rbabel
From: rbabel@babylon.UUCP (Ralph Babel)
Newsgroups: adsp.sw,comp.sys.amiga.tech
Subject: Re: ColdReboot() - The Never Ending Story?
Message-ID: <03065.AA03065@babylon.UUCP>
Date: 16 Aug 90 23:13:21 GMT
References: <03021.AA03021@babylon.UUCP> <13839@cbmvax.commodore.com> <13847@cbmvax.commodore.com>
Lines: 47

In article <13839@cbmvax.commodore.com>
daveh@cbmvax.commodore.com (Dave Haynie) writes:

> If the MMU is on, make sure you're done running any OS
> code before you turn it off.

And if I'm currently executing out of a memory region that
has been remapped?

In article <13847@cbmvax.commodore.com>
valentin@cbmvax.commodore.com (Valentin Pepelea) writes:

> I'm not sure what you are talking about here.

About trying to make ColdReboot() (and other programs using
the RESET instruction) more compatible with existing
hardware (e.g. the A1000).

> I wrote MMUkick with the specific purpose to allow GVP
> accelerator owners to boot OS 2.0 kickfiles.

No-one said that it didn't work absolutely perfectly fine!

I merely pointed out that after a CPU-RESET something might
appear at location 0 (and also at $00e8xxxx - thanks Dave!)
that Exec and Expansion might choke on. Unless you know what
it is, the only way to get rid of this "something" is by
jumping to location 2. Fortunately, this "something" does
not show up on a GVP '030 board unless you remove a jumper.

> Self modifying code is dangerous to your health.

So is jumping into Kickstart. I'm checking for version
numbers and I'm clearing the code cache, so I'm more
compatible than, for example, the 1.3 LoadSeg(). :-)

> In this case, remember to Disable() all interrupts before
> entering the critical region.

Thanks for the reminder! It's one more reason to replace the
current version of ColdReboot() - just imagine an interrupt
coming along after the CPU-RESET has caused all interrupt
vectors to disappear ...

Thanks,

Ralph