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=DKIM_SIGNED,DKIM_VALID, MAILING_LIST_MULTI autolearn=ham autolearn_force=no version=3.4.4 Received: (qmail 19318 invoked from network); 20 Dec 2021 15:44:51 -0000 Received: from minnie.tuhs.org (45.79.103.53) by inbox.vuxu.org with ESMTPUTF8; 20 Dec 2021 15:44:51 -0000 Received: by minnie.tuhs.org (Postfix, from userid 112) id BDB269CE81; Tue, 21 Dec 2021 01:44:46 +1000 (AEST) Received: from minnie.tuhs.org (localhost [127.0.0.1]) by minnie.tuhs.org (Postfix) with ESMTP id 8D4E19490D; Tue, 21 Dec 2021 01:44:14 +1000 (AEST) Authentication-Results: minnie.tuhs.org; dkim=pass (2048-bit key; unprotected) header.d=plonka-us.20210112.gappssmtp.com header.i=@plonka-us.20210112.gappssmtp.com header.b="3MLacerk"; dkim-atps=neutral Received: by minnie.tuhs.org (Postfix, from userid 112) id 99EE69490D; Tue, 21 Dec 2021 01:44:11 +1000 (AEST) Received: from mail-pj1-f42.google.com (mail-pj1-f42.google.com [209.85.216.42]) by minnie.tuhs.org (Postfix) with ESMTPS id 25A0E9461A for ; Tue, 21 Dec 2021 01:44:08 +1000 (AEST) Received: by mail-pj1-f42.google.com with SMTP id y16-20020a17090a6c9000b001b13ffaa625so10739135pjj.2 for ; Mon, 20 Dec 2021 07:44:08 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=plonka-us.20210112.gappssmtp.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=MZGw2GWfXvQYJThGG8sVnkQyFJwJk54JMPyPsnPLagk=; b=3MLacerkC032iugE9xbMGfb7el9xJ+h3or3ALbkjvg8Qpi2vwWDIDMnlVwYoCjLDML iC8cz/i4tuh2lPpoC9P1iaAfqJxbOLzsQzjC/i7bx4+M9/uSa6ypLFaXMxJN7shjOLg1 pQRVnPm/xW2fkOF2BVhsFcgFhudNq1BbUlHew8M84Gw1zVwkWq3C8zlz1qjC/+cKlLo4 KyNOyaub0VVfXzpVV8tSWrPi8rmBjTEfOnW9iI4Hb62XwixcKyJF8npyi8U50Eh5xPbe Tx3vciRmhqpf5BoaMLkAS5fWEvFtg5PXEI5qptI3mod9dbdqQHao3iPZdbd6jd6wDxXo JEYw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=MZGw2GWfXvQYJThGG8sVnkQyFJwJk54JMPyPsnPLagk=; b=n3ZC3MHqHu1YPNPtSm1saTob2FqOyzKBedLV3kcgFt8E5JTWoJfxZOhukMCHnKNwDH YnV3Y9EfAo+oix3s6a/SQFxIq19rvlmcYXtHS8S/Z4TF5OcupkqGMZcsmdRwc0t0sJ5c 87yLJ/aW+F05+LnfUALPQqv+r1vKfOxwCZKjMmGckWn+AeNYX6P93mfRn9QWtd0f51dI DNjG9BI4hFqazgVeObjCMbTeBRNvStYRu+FTVEZaTGARj/+S6tUNnkUWEvJQNJ3IbYM0 qa0ODaamuzxbBsUdDdW0krZIpAqLux7JCjIzPcedpEqX3H8Cwdfiqa18njAvwL9vEG2h 5f/w== X-Gm-Message-State: AOAM5315imLudRWiaSOiaBPtyPloO7mucWIDtKugGzZxrRlbsZJrW3GQ z3cCcYgkkZsXl+JsQCTgzaz+nfDWirNF71PTLrrB8A== X-Google-Smtp-Source: ABdhPJxK2myHfxpm+l1CnHn8jci9f81eN1j+k2SaUC9jQhvKG1PkZsJSwE9a6twhwhDiQsVp5n4Apf3bBhoLnHHJKyE= X-Received: by 2002:a17:903:11c4:b0:141:da55:6158 with SMTP id q4-20020a17090311c400b00141da556158mr17271872plh.7.1640015047566; Mon, 20 Dec 2021 07:44:07 -0800 (PST) MIME-Version: 1.0 References: <55817161-038A-4358-8D4D-2D938578583A@planet.nl> In-Reply-To: <55817161-038A-4358-8D4D-2D938578583A@planet.nl> From: Dave Plonka Date: Mon, 20 Dec 2021 09:43:56 -0600 Message-ID: To: Paul Ruizendaal Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Subject: Re: [TUHS] PDP 11/23 running UNIX version 6 at VCF Midwest! 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 main list Errors-To: tuhs-bounces@minnie.tuhs.org Sender: "TUHS" Hi Paul We talked about this a bit more in the comments on the video, with Gavin doing some experiment afterwards. While at the show, one experiment we did was to redirection the bas(1)ic program's output to a file and what we found was that (a) characters would still sometimes be lost (which is how we determined it's not due to a serial communications, directly and (b) the dropped characters would coalesce together into a small run. Gavin's speculation at the time was that the floppy driver interfered/interrupted the bas' output somehow, since we noticed there was also disk activity coinciding roughly in time with a bout of dropped characters. What is unusual about Gavin's machine (at the time of this video) is that everything was on floppies - including root, tmp, etc. because he did not have a functioning fixed disk yet. It may be a configuration that was rarely used, e.g., scratch space for bas on floppy. (We found bas seems to read the source code from the file system even at runtime.) Any insights welcome - esp. if you can put them in the comments there. Peace, Dave On Sun, Dec 19, 2021 at 11:25 AM Paul Ruizendaal wrote: > > While doing some end of year retrocomputing revisiting, I thought some > of you might enjoy this - there is hope for the next generation(s)! ;) > https://www.youtube.com/watch?v=3D_Zyng5Ob-e8 > > > > Thanks for that video link! > > I noticed the bit at the end about V6 and the occasional dropped charact= er and that this was not a serial line issue. I have the same issue in my V= 6 port to the TI-990 and always assumed that it was a bug I introduced myse= lf when hacking the tty driver. > > Does anyone remember, was this a real life bug back in 6th edition back i= n the 1970=E2=80=99s? Maybe only showing at higher baud rates? > > Paul > --=20 dave@plonka.us http://www.cs.wisc.edu/~plonka/