From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on inbox.vuxu.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=5.0 tests=MAILING_LIST_MULTI, RCVD_IN_DNSWL_NONE autolearn=ham autolearn_force=no version=3.4.4 Received: (qmail 19828 invoked from network); 15 Apr 2021 05:12:18 -0000 Received: from minnie.tuhs.org (45.79.103.53) by inbox.vuxu.org with ESMTPUTF8; 15 Apr 2021 05:12:18 -0000 Received: by minnie.tuhs.org (Postfix, from userid 112) id B4EC59C209; Thu, 15 Apr 2021 15:12:08 +1000 (AEST) Received: from minnie.tuhs.org (localhost [127.0.0.1]) by minnie.tuhs.org (Postfix) with ESMTP id 3E0419B6AC; Thu, 15 Apr 2021 15:11:24 +1000 (AEST) Received: by minnie.tuhs.org (Postfix, from userid 112) id 8DE5C94EE1; Thu, 15 Apr 2021 15:11:20 +1000 (AEST) X-Greylist: delayed 598 seconds by postgrey-1.36 at minnie.tuhs.org; Thu, 15 Apr 2021 15:11:19 AEST Received: from castor.opentrend.net (li1631-87.members.linode.com [172.104.51.87]) by minnie.tuhs.org (Postfix) with ESMTP id 8660E94EE1 for ; Thu, 15 Apr 2021 15:11:19 +1000 (AEST) Received: from mira.opentrend.net (mira.opentrend.net [119.18.33.224]) by castor.opentrend.net (Postfix) with ESMTP id 2B9E65A1D8 for ; Thu, 15 Apr 2021 05:01:18 +0000 (UTC) Date: Thu, 15 Apr 2021 15:01:01 +1000 (AEST) From: Robert Brockway X-X-Sender: robert@mira.opentrend.net To: The Eunuchs Hysterical Society In-Reply-To: Message-ID: References: <0BD38829-5E79-4034-BCEF-0555434E52A4@planet.nl> User-Agent: Alpine 2.21 (DEB 202 2017-01-01) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Subject: Re: [TUHS] SUN (Stanford University Network) was PC Unix X-BeenThere: tuhs@minnie.tuhs.org X-Mailman-Version: 2.1.26 Precedence: list List-Id: The Unix Heritage Society mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: tuhs-bounces@minnie.tuhs.org Sender: "TUHS" On Sat, 10 Apr 2021, Dave Horsfall wrote: > On Fri, 9 Apr 2021, Paul Ruizendaal via TUHS wrote: > >> Z80 CP/M machines were still competitive in 1981-1983 (Osborne, Kaypro) > > And the Aussie Microbee... Wonderful machine, and easily hacked upon. > > For example, you could expand the memory by soldering several chips on top of > each other and addressing the CS* line via bank-switching. That worked on the old Radio Shack (Tandy) Color Computer 2 as well. Until this moment I didn't know it had been demonstrated on any other architecture. The Operating System OS-9[1] Level One would detect this and use the bank-switched memory if it was available. Presumably it kept identical copies of itself in each bank as the entire address space switched. Microware OS-9 was *nix-like in look and feel although it was very different internally I think. OS-9 still exists today. I started with OS-9 and so found Unix a comfortable environment when I transitioned over. [1] Which should not be confused with any operating system running on a Mac. That's another story. Rob