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: 103376,5385624f72218ba7 X-Google-Attributes: gid103376,public X-Google-ArrivalTime: 2001-11-12 10:51:09 PST Path: archiver1.google.com!news1.google.com!sn-xit-02!supernews.com!news.tele.dk!small.news.tele.dk!195.54.122.107!newsfeed1.bredband.com!bredband!news000.worldonline.se!news010.worldonline.se!not-for-mail Message-ID: <3BF019F4.C9C460E5@mida.se> From: Mats Karlssohn Organization: MIDA Systemutveckling AB X-Mailer: Mozilla 4.77 [en] (WinNT; U) X-Accept-Language: en MIME-Version: 1.0 Newsgroups: comp.lang.ada Subject: Re: AdaOS References: <9r8pvf$vms$1@papyrus.erlm.siemens.de> <9rk11n$e4n$1@plutonium.btinternet.com> <9rk749$ndt$1@papyrus.erlm.siemens.de> <9rnid9$541$1@neptunium.btinternet.com> <9s3u20$10s0sv$1@ID-25716.news.dfncis.de> <9s670f$u2e$1@papyrus.erlm.siemens.de> <9s74eb$12b2bq$1@ID-25716.news.dfncis.de> <9s76dh$ls0$1@nh.pace.co.uk> <9s9413$11mrei$1@ID-25716.news.dfncis.de> <071120011028298704%philip@no-spam.cs.uwa.edu.au> <9scke6$12jb14$1@ID-25716.news.dfncis.de> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Date: Mon, 12 Nov 2001 19:50:28 +0100 NNTP-Posting-Host: 213.204.137.47 X-Trace: news010.worldonline.se 1005591044 213.204.137.47 (Mon, 12 Nov 2001 19:50:44 MET) NNTP-Posting-Date: Mon, 12 Nov 2001 19:50:44 MET Xref: archiver1.google.com comp.lang.ada:16354 Date: 2001-11-12T19:50:28+01:00 List-Id: Ted Dennison wrote: > > In article <9scke6$12jb14$1@ID-25716.news.dfncis.de>, Nick Roberts says... > > > >Yes, but Phil, it's not the actual bits of software that are redundant -- > >I've no doubt they indeed do useful things -- it's the term 'HAL' that's > >redundant. The hardware abstraction layer IS the device drivers, and always > >has been. Someone's just invented a fancy name, that's all! > > I think there's a bit more to it than that. I believe its purpose initially was > to shelter the kernel from processor implemenation details, so that only the HAL > would have to be rewritten to support a new processor. In that respect, you can > kind of think of it as a microkernel. As usual you are quite right Ted. Please correct me if I'm workn, but I've been led to belive that in NT the main purpose of the HAL is to isolate the device drivers from the architectural differenses of of different processors and machines. Like the difference between the separate I/O addresspace of the x86 vs. {alpha,mips} memory mapped I/O, the idea is that the same device driver can be used for a card, it doesn't matter weather the card is in a AlphaStation or an Intel box. There is more to it though (as usual). -- Mats Karlssohn, developer mailto:mats@mida.se Mida Systemutveckling AB http://www.mida.se Box 64, S-732 22 ARBOGA, SWEDEN Phone: +46-(0)589-89808 Fax: +46-(0)589-89809