Path: utzoo!utgpu!news-server.csri.toronto.edu!rutgers!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: <03189.AA03189@babylon.UUCP>
Date: 21 Aug 90 00:34:49 GMT
References: <03021.AA03021@babylon.UUCP> <13839@cbmvax.commodore.com> <13847@cbmvax.commodore.com> <03065.AA03065@babylon.UUCP> <13895@cbmvax.commodore.com> <892@boink.UUCP> <03125.AA03125@babylon.UUCP> <6397@sugar.hackercorp.com>
Lines: 58

In article <13895@cbmvax.commodore.com>
daveh@cbmvax.commodore.com (Dave Haynie) writes:

> If you're mapping memory that's not ROM code and not
> virtual memory, try to figure out why you've mapped it;
> there's probably not a good reason for this.

Well, I didn't remap anything (except for FASTROM, my own
debugging tools, and some VM experiments), but do _I_ know
what other people are using the MMU for?

> First of all, when you have ColdReboot() (eg, OS 2.0 and
> later), any program using RESET other than ColdReboot() is
> probably in error.

I agree, but you misunderstood me! All the time I was
basically referring to the 1.3-compatible version of
ColdReboot() (the one from AmigaMail).

> A ColdReboot() cannot legally give you back something at
> location 0 or $00e8xxxx that is not understood by Exec and
> Expansion.

But I don't even want it back! All I want is that the 1.3
version of ColdReboot() takes care of the A1000 WCS etc. And
the version I posted (plus the fix Valentin suggested)
exactly does that.

> Since ColdReboot() is a perfectly valid thing to do under
> AmigaOS, any hardware that prevents that action from doing
> what's expected is wrong.

Sure, you're 100% right. But if ColdReboot() can be made
_more_ compatible than it is right now, why not do it?

In article <6397@sugar.hackercorp.com>
peter@sugar.hackercorp.com (Peter da Silva) writes:

>> Sure, they're still at $f80000, but what Dave probably meant
>> to say was: You cannot make them reappear at location 0 (and
>> the special registers at $e8xxxx) without a _hard_ RESET
>
> What about with judicious use of the MMU?

Sorry, no. You might be able to move the ROM image back to
location 0, but the registers at $e8xxxx are gone. Similar
to the expansion space of a memory board (the area that gets
copied to an ExpansionRom structure) or a board that is told
to "shut up", once you strobe a certain bit/byte/whatever,
the registers are no longer part of your address space.

If you plan to intercept that strobe with the help of a
RESET-resident utility using the MMU, sorry again! The
special registers at $e8xxxx _have_to_ move/disappear,
before the expansion.library can start its AutoConfig
process.

Ralph