Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!linus!decvax!harpo!eagle!mhuxl!cbosgd!ihnp4!inuxc!pur-ee!uiucdcs!uokvax!andree From: andree@uokvax.UUCP Newsgroups: net.micro.68k Subject: Re: Re: CPM-68K and market question? - (nf) Message-ID: <3490@uiucdcs.UUCP> Date: Thu, 27-Oct-83 23:12:45 EST Article-I.D.: uiucdcs.3490 Posted: Thu Oct 27 23:12:45 1983 Date-Received: Mon, 31-Oct-83 09:06:36 EST Lines: 49 #R:cbosgd:-46600:uokvax:12700006:000:1841 uokvax!andree Oct 26 08:51:00 1983 Here is something found in net.micro.6809 which gives several other good reasons for running os-9/68k as opposed to Unix. I would also like to point out that os/9 can be ported to existing hardware WITHOUT having to pay an arm and a leg for a source license. That's why I'm upgrading my z80 to a 68k os/9 system... /***** uokvax:net.micro.6809 / emjej / 8:47 am Oct 26, 1983 */ No, that's not quite it. OS-9 is a Unix-like OS that is designed with the personal computer in mind. (That and the unique, at the time, capabilities of the 6809.) For example, hard disks adequate for use as swap devices are *very* expensive (even now)--so OS-9 doesn't swap, since on a typical (affordable) micro there won't be a fvery fast hard disk. One won't necessarily have huge amounts of memory, so OS-9 uses the memory it has as well as it can (requiring machine-language programs to be position independent and re-entrant, so that only one copy of a program need be in memory at at time, making the shell as small as it is (they had to make a judgement call about what to leave in, but they crammed a lot into 1K (!!!)). This, along with rethinking of other stuff and not having the warts that came up during the evolution of Unix, has led to quite a clean OS. Indeed, not having memory management as a crutch has led to the memory module being in rather like a Multics segment. (It looks like it would work well as an implementation technique for CLU clusters/. OS-9/68K is largely written in C (the 6809 version is mostly assembumbler), so it should be fairly easy to port to other machines. (It will come in three flavors--Levels One and Two, corresponding to the 6809 Levels One and Two, and Level Three, for those with 68010 systems.) James Jones /* ---------- */