From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on inbox.vuxu.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=5.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,RCVD_IN_DNSWL_NONE autolearn=ham autolearn_force=no version=3.4.2 Received: from minnie.tuhs.org (minnie.tuhs.org [45.79.103.53]) by inbox.vuxu.org (OpenSMTPD) with ESMTP id 78bdadc4 for ; Sun, 23 Jun 2019 12:21:02 +0000 (UTC) Received: by minnie.tuhs.org (Postfix, from userid 112) id 3383394F8F; Sun, 23 Jun 2019 22:21:01 +1000 (AEST) Received: from minnie.tuhs.org (localhost [127.0.0.1]) by minnie.tuhs.org (Postfix) with ESMTP id 2581194F68; Sun, 23 Jun 2019 22:20:37 +1000 (AEST) Received: by minnie.tuhs.org (Postfix, from userid 112) id D62C594F6B; Sun, 23 Jun 2019 22:20:33 +1000 (AEST) Received: from smtp-out-2.mxes.net (unknown [205.237.194.127]) by minnie.tuhs.org (Postfix) with ESMTPS id 2D2AC94F68 for ; Sun, 23 Jun 2019 22:20:33 +1000 (AEST) Received: from Customer-MUA (mua.mxes.net [10.0.0.1]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.mxes.net (Postfix) with ESMTPSA id 0955027506; Sun, 23 Jun 2019 08:20:22 -0400 (EDT) Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (1.0) From: Ron Natalie X-Mailer: iPhone Mail (16F203) In-Reply-To: Date: Sun, 23 Jun 2019 08:16:47 -0400 Content-Transfer-Encoding: 7bit Message-Id: <38B5393D-5316-484F-B499-2931E8C0C035@ronnatalie.com> References: To: Rudi Blom X-Sent-To: Subject: Re: [TUHS] Any oldtimers remember anything about the KS11 on the 11/20? 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: , Cc: tuhs Errors-To: tuhs-bounces@minnie.tuhs.org Sender: "TUHS" We always referred to CSS as the DEC kludge department. Sent from my iPhone > On Jun 22, 2019, at 22:37, Rudi Blom wrote: > > Probably already known, but to be sure > > Interesting options: MX11 - Memory Extension Option: this enabled the > usage of 128 KW memory (18-bit addressing range); KS11: this option > provided hardware memory protection, which the plain /20 lacked. Both > options were developed by the Digital CSS (Computer Special Systems). > http://hampage.hu/pdp-11/1120.html > > PS the page listed below has a very nice picture of the 'two fathers > of UNIX" working on a PDP-11/20 > http://hampage.hu/unix/unix1.html