From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stas Sergeev Subject: Re: increase base memory Date: Mon, 16 Dec 2002 21:09:06 +0300 Sender: linux-msdos-owner@vger.kernel.org Message-ID: <3DFE16C2.8000600@yahoo.com> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: List-Id: Content-Type: text/plain; charset="us-ascii"; format="flowed" To: linux-msdos@vger.kernel.org Hello. Sergey Suleymanov wrote: > Stas> Increasing the base memory above 640Kb is definitely the bad > Stas> idea, as it is used very rarely even in a pure DOS and will > Stas> cost you the inability to display graphics. > By the way, 0.99.13 (pre-1.0) works well with 704k base. ;) How "well" did it work? Working without graphics is definitely not "well" and I bet some graphics modes should be broken (if not all). Furthermore the programs expect the video mem to be where it must be, so in that case it will just write to its own memory (corrupting it) trying to write to a video memory. This must be rather safe for the text modes however, so as the text buffer starts at 0xb000 IIRC. There is a bug in a parser: it calls stop_video() for some reasons and it changes the base mem to 640 when started under console. This must be resolved somehow, I guess Bart knows what's going on there. But if it would be me, I'd just disallow more than 640Kb by erroring and terminating dosemu right away. I haven't got an answer yet, why is this really necessary? Are you always using a "vidram" under real dos? I guess you are not, but then why should that be used under dosemu? That's weird and unsafe, why anyone should be willing to do this? You can use UMB and HMA, is it not enough? Well, if that is just a comparison with 0.99.13, then you are right, there is a bug in a parser.y.in now which must be fixed, but that still doesn't mean that >640 should be used on a regular basis after this is fixed.