Received: from ELI.CS.YALE.EDU by BUGS.SYSTEMSY.CS.YALE.EDU; Fri, 10 Aug 90 03:43:03 EDT Received: from life.ai.mit.edu ([128.52.32.80]) by ELI.CS.YALE.EDU; Fri, 10 Aug 90 03:41:44 EDT Received: from watsun.cc.columbia.edu by life.ai.mit.edu (4.1/AI-4.10) id AA29183; Fri, 10 Aug 90 03:09:06 EDT Received: by watsun.cc.columbia.edu (5.59/FCB) id AA20072; Fri, 10 Aug 90 03:09:21 EDT Date: Fri, 10 Aug 90 3:09:20 EDT From: Charles Lasner To: PDP8-LOVERS@ai.mit.edu Message-Id: Date: Fri, 10 Aug 90 3:09:20 EDT From: Charles Lasner To: PDP8-LOVERS@ai.mit.edu From: Charles Lasner To: PDP8-LOVERS@AI.MIT.EDU Subject: Testing I am testing a new mail path from this machine, watsun, which is a Sun work-station currently running SunOS, V 4.1 (as of last week!). They finally got the e-mail program to work! Please have someone reply to me to confirm the path works. I would appreciate it if this mail comes back to me in some appropriate form including this original text, since apparently I will have to archive my own mail and responses, since there isn't any active goings on. I have a file called PDP8-LOV. which is about 135k long. I notice it appears to be an archive from mostly last year, not currently being updated as was indicated. I will also assume that many issues raised in it were never "properly" addressed, as most news forums that get fragmented are prone to. I intend to go through it carefully and respond where I feel I can contribute, etc. I see a lot of misinformation here, mostly the uninformed being those "deaf" who lead around the "dumb" who lead the "blind" and it cries out for the benefit of my uninterrupted PDP-8 programming and hardware experiences since 1968. I wish I had known about this back then, but better late than never. Also, apparently the gap between the latest message in this file and the recent past of a few months ago is lost? I hope I am wrong, so I can update my own copy (restricted currently to only this 135k file). If anyone can help reconstruct this archive, please respond or forever hold your XX2247 ACE Lock Keys! Unless someone has a better idea, I will invent my own message numbering scheme, subject to change as necessary. Btw, I understand that there is interest in the PDP-8 usage of the SyQuest and other SCSI drives out there. Before I go into any detail, will someone please respond NOW that the multi-kilobucks price of some of these configurations doesn't scare them off! I am not selling them, I just write support code for the beasts. I am willing to "tell all" if necessary, but they ain't cheap! These things are not on the used market (yet!). cjl (lasner@watsun.cc.columbia.edu) Received: from ELI.CS.YALE.EDU by BUGS.SYSTEMSY.CS.YALE.EDU; Fri, 10 Aug 90 03:46:56 EDT Received: from life.ai.mit.edu ([128.52.32.80]) by ELI.CS.YALE.EDU; Fri, 10 Aug 90 03:45:34 EDT Received: from watsun.cc.columbia.edu by life.ai.mit.edu (4.1/AI-4.10) id AA29360; Fri, 10 Aug 90 03:19:56 EDT Received: by watsun.cc.columbia.edu (5.59/FCB) id AA20010; Fri, 10 Aug 90 02:59:06 EDT Date: Fri, 10 Aug 90 2:59:06 EDT From: Charles Lasner To: PDP8-LOVERS@ai.mit.edu Cc: Testing@watsun.cc.columbia.edu Message-Id: Date: Fri, 10 Aug 90 2:59:06 EDT From: Charles Lasner To: PDP8-LOVERS@ai.mit.edu Cc: Testing@watsun.cc.columbia.edu From: Charles Lasner To: PDP8-LOVERS@AI.MIT.EDU Subject: Testing I am testing a new mail path from this machine, watsun, which is a sun work-station currently running SunOS, V. 4.1 (as of last week!). They finally got the e-mail program to work! Please have someone reply to me to confirm the path works. I would appreciate it if this mail comes back to me in some appropriate form including this original text, since apparently I will have to archive my own mail and responses, since there isn't any active goings on. I have a file called PDP8-LOV. which is about 135k long. I notice it appears to be an archive from mostly last year, not currently being updated as you indicated. I will also assume that many issues raised in it were never "properly" addressed, as most news forums that get fragmented are prone to. I intend to go through it carefully and respond where I feel I can contribute, etc. I see a lot of misinformation here, mostly the uninformed being those "deaf" who lead around the "dumb" who lead the "blind" and it cries out for the benefit of my uninterrupted PDP-8 programming and hardware experiences since 1968. I wish I had known about this back then, but better late than never. Also, apparently the gap between the latest message in this file and the recent past of a few months ago is lost? I hope I am wrong, so I can update my own copy restricted currently to only this 135k file. If anyone can help reconstruct this archive, please respond or forever hold your XX2247 ACE Lock Keys. Unless someone has a better idea, I will invent my own message numbering scheme, subject to change as necessary. Btw, I understand that there is interest in the PDP-8 usage of the SyQuest and other SCSI drives out there. Before I go into any detail, will someone please respond NOW that the multi-kilobucks price of some of these configurations doesn't scare them off! I am not selling them, I just write support code for the beasts. I am willing to "tell all" if necessary, but they ain't cheap! These things are not on the used market (yet!). cjl (lasner@watsun.cc.columbia.edu) Received: from ELI.CS.YALE.EDU by BUGS.SYSTEMSY.CS.YALE.EDU; Fri, 10 Aug 90 05:37:28 EDT Received: from life.ai.mit.edu ([128.52.32.80]) by ELI.CS.YALE.EDU; Fri, 10 Aug 90 05:36:07 EDT Received: from watsun.cc.columbia.edu by life.ai.mit.edu (4.1/AI-4.10) id AA00254; Fri, 10 Aug 90 05:12:04 EDT Received: by watsun.cc.columbia.edu (5.59/FCB) id AA20618; Fri, 10 Aug 90 05:12:20 EDT Date: Fri, 10 Aug 90 5:12:19 EDT From: Charles Lasner To: PDP8-LOVERS@ai.mit.edu Subject: Belated Mail Reply Message-Id: Date: Fri, 10 Aug 90 5:12:19 EDT From: Charles Lasner To: PDP8-LOVERS@ai.mit.edu Subject: Belated Mail Reply >Received: from AI.AI.MIT.EDU (CHAOS 3130) by MC.LCS.MIT.EDU 18 Feb 89 10:32:35 EST >Date: Sat, 18 Feb 89 10:32:31 EST >From: "Robert E. Seastrom" >To: pdp8-lovers@MC.LCS.MIT.EDU >Message-ID: <540513.890218.RS@AI.AI.MIT.EDU> > > >Well, folks, it's finally here. The PDP8-LOVERS mailing list is now >reality! Messages for the list go to PDP8-LOVERS@MC.LCS.MIT.EDU; >requests to be added to or deleted from the list go to >PDP8-LOVERS-REQUEST@MC.LCS.MIT.EDU (case is _not_ critical here). > >Perhaps we ought to all introduce ourselves to each other... > > This one's for you <7001> > > -Rob From: cjl Let me introduce myself. I am Charles J. Lasner. I only use the J to get my initials, which I usually go by, thus cjl. I am a PDP-8 programmer. I don't know how many of us there are left, but I started in 1968 with a straight -8 table-top machine at Brooklyn PolyTechnic Institute. The school probably has another name by now, due to academia's answer to the business world's phenomena of acquisitions and mergers. The machine in question is quite legendary. The work done on it is responsible in LARGE part for why all of us are here reading this, since this is the "original" PDP-8 used by the legendary Richard Lary and company. If it can be said that the PDP-8 created the phrase "mini-computer", then it is THIS PDP-8 that made the "mini-computer" into something other than a paper-tape machine! This PDP-8 was originally configured by the academics in charge as a programmer's disaster: 4K, EAE, a model 33 teletype, AF01A A-D converter with 16-channel multiplexor, AA01A D-A converter with (wow!) THREE channels. A Bud blue rack cabinet housed the A-D and D-A with lots of empty space. All empty slots had those wonderful super-thick zinctone panels, and the fronts were all in place; they were held in place with those pressed-in heavy shiny metal threaded bosses that most of you can't figure out the purpose of on your wire-wrap racks. As far as I know, these were the only style of cabinet that the bosses were supplied for. The plates used heavy nickel-plated knurled knobs with a screw-driver slot you could turn with a dime. Soon after all of this arrived, and got nowhere due to the enormous waste of time paper-tape can be (especially at 110 baud and unreliable at that!), a DEC salesman suggested a high-speed reader/punch be added. Fortunately for all of us, THIS NEVER HAPPENED, for if it had, no further work of external significence would have been done. (The EE department would have been very happy to just develop their diddly A-D and D-A experiment programs.) Due to the efforts of Richard Lary, Jack Burness, Hank Maurer, Lenny Elekman, and Joseph R. Fischetti (to name a few legends I knew), the EE department was convinced to spend MORE money on some new-fangled beast the salesman had vaguely heard of; he was fairly certain it was called a MicroTape. This was, of course, an early name for DECtape. So the EE department shelled out another $8k and got itself another Bud blue rack cabinet complete with sides, another power controller, 11 buss cables, and a TC01 and one (yes one!) TU55 DECtape drive. The academics thought that the drive was custom made for the PDP-8, because the numeral "8" always appeared on the drive select. (No need to change drives when you have only one of them!) I later found out why the "8" was there (not "0"): This is a throwback to the earlier Microtape drives used mostly on the PDP-6 which are really DECtape drives, but with an entirly different interface to the PDP-8, which really belongs to the PDP-5 era. I believe that the PDP-5 doesn't support 3-cycle data-break, because this is a single-cycle interface. This limits programming possibilities. (Another subject entirely!) I believe the only programming for this earlier hardware was an original version of the DECtape Library System which I had contact with on the TC01/TU55 (an incompatible later version, but obviously less obscure). The interesting point is that while the TC01 has a three-bit drive select register, where all cases are viable, this earlier hardware had a FOUR-bit register, so drives had to be selected as 1-8. Clearing the register deselects all drives, whereas when talking to the "Solid-State DECtape" drive, as the TU55 was originally known, you are selecting drive zero. Apparently there were hardware adaptations to theoretically connect the TU55 as a microtape drive (using RELAY LOGIC level converters instead of the jumper cards usually in the drives), so they thought in terms of the original microtape nomenclature of 1-8. Years later (I think first done for the benefit of the PDP-12 LINCtape) they had an ECO to glue a 0 over the 8. Soon after the TC01/TU56 cabinet arrived, the 33 teletype started failing (which is normal!) from "normal" use (reading paper-tapes!). They had their first "run-in" with DEC Field Service, whose members sort of knew what to do with the -8, but they KILLED teletypes! Eventually, they purchased a PT08, the only hardware on this machine to use ICs (RTL chips only, TTL came later!). With it came an additional teletype, a model 35 (without paper-tape). The 35 became the 03/04-connected one, and the 33 was "banished" to the PT08. (And over the years it "walked" out of the PDP-8 room to be "borrowed" by various groups, only to be "retrieved" periodically.) Fortunately, a private teletype maintenance company contacted the school and eventually won a teletype-only maintenance contract, over DEC's objections. Since these teletypes were so over-used, it became necessary to rotate them between the PT08 and the console to keep them working. We even created software to SLOW DOWN the teletype, since it was noticed that an out-of-adjustment 35 will work FINE if run at 89% of maximum speed (that's 89% of 110 baud!) when it starts jumbling characters at 100% speed. This machine was setup on a large desk, with the teletypes nearby, and a Bud cabinet at either end. We didn't have the nice Formica table option. So much software was toggled into this machine that I personally replaced the slide switches which wore out! I also repaired the CPU several years later, after DEC Field Service swore they couldn't get it to work after 9 months of trying. The problem was that there are isolation diodes in the wires that run from various registers to the light panel, which has lamp drivers and soldered in lamps on it. Periodically we would replace the occasional blown transistor driver and numerous blown bulbs. (Touching the panel was a calculated risk since you killed even more lamps by doing it!) The diodes are located on the card edge where all of the wires are soldered close together, and plugged into the backplane; there are several such cards. The wires break off easily, and hasty repairers would sloppily solder them back to the board lugs. Eventually some diodes shorted, so the capacitance of the wires now loaded the affected driver. Also there now was the possibility of cross-talk between the wires collector-triggering the gates! This is why the machine was so prone to random failure. (It worked in single-step mode.) Replacing the diodes didn't completely work, because there was yet another problem: the diodes were photo-sensitive! DEC attempted to light-shield the diodes by painting them. This paint got scraped off of them due to the soldering, etc., so the machine was sensitive to its own lamps being lit! It worked better in room darkness, so we got the idea about inadvertent photo-diodes! Painting the diodes solved the last remaining problem. I almost single-handedly got the machine back up (there were other random problems as well, but they were easier to solve, like the tendancy for a PT08 to burn up a land UNDER a chip where you couldn't see it!), and got the thanks of the faculty members of the EE department, who would have scrapped the machine if it was unrepairable! Although this wasn't my first computer, it was my first DEC computer. I have stayed with the PDP-8's to this day. I was then and now a programmer, but we all participated in keeping the machine up. I can trace my extensive DEC hardware background to this beginning (as well as DEC software!). cjl (Charles Lasner) (lasner@watsun.cc.columbia.edu or lasner@cunixf.cc.columbia.edu) Received: from ELI.CS.YALE.EDU by BUGS.SYSTEMSY.CS.YALE.EDU; Mon, 13 Aug 90 02:55:15 EDT Received: from life.ai.mit.edu ([128.52.32.80]) by ELI.CS.YALE.EDU; Mon, 13 Aug 90 02:53:57 EDT Received: from watsun.cc.columbia.edu by life.ai.mit.edu (4.1/AI-4.10) id AA07593; Mon, 13 Aug 90 02:26:23 EDT Received: by watsun.cc.columbia.edu (5.59/FCB) id AA10158; Mon, 13 Aug 90 02:25:16 EDT Date: Mon, 13 Aug 90 2:25:15 EDT From: Charles Lasner To: PDP8-LOVERS@ai.mit.edu Message-Id: Date: Mon, 13 Aug 90 2:25:15 EDT From: Charles Lasner To: PDP8-LOVERS@ai.mit.edu From: Charles Lasner To: PDP8-LOVERS@ai.mit.edu Subject: Belated Mail Reply > Received: from AI.AI.MIT.EDU (CHAOS 3130) by MC.LCS.MIT.EDU 18 Feb 89 10:32:35 EST > Date: Sat, 18 Feb 89 10:32:31 EST > From: "Robert E. Seastrom" > To: pdp8-lovers@MC.LCS.MIT.EDU > Message-ID: <540513.890218.RS@AI.AI.MIT.EDU> > > > > Well, folks, it's finally here. The PDP8-LOVERS mailing list is now > reality! Messages for the list go to PDP8-LOVERS@MC.LCS.MIT.EDU; > requests to be added to or deleted from the list go to > PDP8-LOVERS-REQUEST@MC.LCS.MIT.EDU (case is _not_ critical here). > > Perhaps we ought to all introduce ourselves to each other... > > This one's for you <7001> > > -Rob From: cjl Subj: This one's for you <7001> 7001 is not a one; 7201 is a one! 7001 is IAC which assumes a CLEAR AC; 7201 is CLA IAC which ensures 0001 in the AC. Better still is 7301 which is CLA CLL IAC which makes the link clear as well. An alternate way to set the AC to one with a clear link is CLA CLL CML RAL (7324), but this won't work on the PDP-8/S (a mixed blessing!) or possibly the PDP-5 (?). If the machine has EAE, then perhaps the best is to use CLA MQL first! If you use double precision, then do an MQL after setting the AC to one; this would then be the double precision value 00000001. So when getting a one for me, make sure it IS a one <7301>. (with apologies to Bud Lite commercials) cjl (Charles Lasner) (lasner@watsun.cc.columbia.edu or lasner@cunixf.cc.columbia.edu) Received: from ELI.CS.YALE.EDU by BUGS.SYSTEMSY.CS.YALE.EDU; Mon, 13 Aug 90 09:33:26 EDT Received: from life.ai.mit.edu ([128.52.32.80]) by ELI.CS.YALE.EDU; Mon, 13 Aug 90 09:32:09 EDT Received: from EDDIE.MIT.EDU by life.ai.mit.edu (4.1/AI-4.10) id AA10200; Mon, 13 Aug 90 09:14:10 EDT Received: by EDDIE.MIT.EDU (5.61/25-eef) id AA02421; Mon, 13 Aug 90 08:11:09 EST Date: Mon, 13 Aug 90 08:11:09 EST From: Robert E. Seastrom Message-Id: <9008131311.AA02421@EDDIE.MIT.EDU> To: lasner@watsun.cc.columbia.edu Cc: PDP8-LOVERS@ai.mit.edu In-Reply-To: Charles Lasner's message of Mon, 13 Aug 90 2:25:15 EDT Date: Mon, 13 Aug 90 08:11:09 EST From: Robert E. Seastrom To: lasner@watsun.cc.columbia.edu Cc: PDP8-LOVERS@ai.mit.edu In-Reply-To: Charles Lasner's message of Mon, 13 Aug 90 2:25:15 EDT Date: Mon, 13 Aug 90 2:25:15 EDT From: Charles Lasner From: cjl Subj: This one's for you <7001> 7001 is not a one; 7201 is a one! 7001 is IAC which assumes a CLEAR AC; 7201 is CLA IAC which ensures 0001 in the AC. Better still is 7301 which Um, IAC was precisely what I meant... I wanted to give people one more, not take away everything they had and leave them with 1. :-) ---Rob