From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00 autolearn=ham autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,95dad97c56f9de95 X-Google-Attributes: gid103376,public X-Google-ArrivalTime: 2001-09-25 06:10:39 PST Path: archiver1.google.com!newsfeed.google.com!newsfeed.stanford.edu!newsfeeds.belnet.be!news.belnet.be!colt.net!newspeer.clara.net!news.clara.net!news5-gui.server.ntli.net!ntli.net!news6-win.server.ntlworld.com.POSTED!not-for-mail From: "chris.danx" Newsgroups: comp.lang.ada References: Subject: Re: Curiousity: pragma No_Run_Time for Gnat X-Priority: 3 X-MSMail-Priority: Normal X-Newsreader: Microsoft Outlook Express 5.50.4807.1700 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4807.1700 Message-ID: Date: Tue, 25 Sep 2001 14:05:32 +0100 NNTP-Posting-Host: 213.104.122.251 X-Complaints-To: abuse@ntlworld.com X-Trace: news6-win.server.ntlworld.com 1001423132 213.104.122.251 (Tue, 25 Sep 2001 14:05:32 BST) NNTP-Posting-Date: Tue, 25 Sep 2001 14:05:32 BST Organization: ntlworld News Service Xref: archiver1.google.com comp.lang.ada:13322 Date: 2001-09-25T14:05:32+01:00 List-Id: > But note that for OS execution it would be acceptable to depend on the > BIOS (at least early on the startup process); after all the BIOS is there > and it is running before the OS. *** But it is not acceptable at all for > execution to depend on another OS. *** > > In fact, I have been thinking in terms of a MIOS (Minimal Input/Output > System) package providing access to the "minimal system" I have suggested > before (Ada_OS talk) as a starting target (floppy, keyboard, screen): MIOS > would probably be implemented with BIOS services: hence, in part, the > tribute in its name. Note: if you want a pmode OS for the x86+ this could only work via v86 mode or only in the very early stages of bootup (which GRUB might be good for). Using BIOS via v86 would be slow and OS developers only do this for vesa (because graphics cards -- in particular those with nVidia chipsets -- don't release the prog. specs for their cards). However for initial start up such a system would be good but you may need a 16bit compiler for real mode stuff. Keyboard handlers for pmode seem to be easy enough, so too does the screen. In fact programming the screen (for text, graphics programming is more complex) is really easy. You write to address 0xb8000 in attribute/character pairs for colour memory or something (don't quote me on that) in pmode. > BTW, what is GRUB? And where is GNORT? GRUB is a bootloader for OSes, in particular it can boot multiple OS from a menu with a multiboot compliant header, *I think* (but it's supposed to boot almost anything). GNORT is a some kind of GNAT variant provided by ACT, which seems to be have discontinued and either integrated into or changed it's name to GNAT Pro Bare Board.