From mint-bounce@lists.fishpool.fi Tue Sep 9 14:39:59 2008 Subject: Re: [MiNT] Supexec taking one VBL? From: Petr =?ISO-8859-1?Q?Stehl=EDk?= To: mint@lists.fishpool.fi In-Reply-To: <1220980904.6363.30.camel@localhost> References: <1220980904.6363.30.camel@localhost> Content-Type: text/plain; charset=ISO-8859-2 Date: Tue, 09 Sep 2008 20:04:35 +0200 Message-Id: <1220983475.6238.28.camel@joy> Mime-Version: 1.0 X-Mailer: Evolution 2.22.3.1 X-Approved-By: tjhukkan@fishpool.fi X-ecartis-version: Ecartis v1.0.0 Sender: mint-bounce@lists.fishpool.fi Errors-to: mint-bounce@lists.fishpool.fi X-original-sender: pstehlik@sophics.cz Precedence: bulk List-help: List-unsubscribe: List-Id: X-List-ID: List-subscribe: List-owner: List-post: Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by mail.sparemint.org id m89IdxZa018057 Thomas Reiss píše v Út 09. 09. 2008 v 19:21 +0200: > The Amiga OS never had any memory protection and will never have mainly > because of the message passing stuff - I can't get into more details, > sorry. The MMU is however used by some debugging tools to detect > unexpected memory accesses, etc. > Of course, without any protection, you can access anything and trash > everything you want but the OS provides such nice stuff as described by > Miro that prevents you from banging the hardware. The Amiga OS most probably does not *prevent* it (if I understand your explanation above correctly) but makes it *unnecessary* and the Amiga programmers are so smart/lazy/disciplined that are not trying to work with the hardware directly. That's actually the purpose of a good operating system - to separate applications from underlying hardware by providing functions that do what's necessary. Unfortunately TOS does offer just a few XBIOS functions and those are either slow or buggy so programmers tend to skip them and try to drive the hardware directly. It's obvious that if an OS like FreeMiNT wants to prevent applications from messing with hardware it must first offer an API that will cover everything (demo/game) programmers usually need. When this becomes part of FreeMiNT then programmers might start using it and slowly start rewriting old and creating new games and demos for FreeMiNT. Another obvious thing (if we want to stay in this sci-fi land for another paragraph) is that the API must be accessible in other major systems used on our hardware (TOS, MagiC) so there should probably be a library that the game/demo programmers ("coders" :) could link or distribute with their 'products'. Well, I'd suggest to check the libSDL (www.libsdl.org) - maybe it's close to what they need. If not then I am afraid it's about 22 years late for inventing a better XBIOS... Petr