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101090 discussions

Reproducing old machines with newer technology (Re: PDP-12 at the RICM)

by jnc＠mercury.lcs.mit.edu

> From: Sean Caron > Many examples of blinkenlights eye candy throughout computer history It wasn't _just_ eye candy; it was a real help in problem debugging (when the machine was stopped), and you could tell a lot about what the machine was doing (when it was running) from the way the lights changed. When the overall machine cost came down, they were too expensive to be worth what they cost, though. Speaking of lights for feedback, anyone remember the 'run bar' - or whatever they called it, my memory fails me - on the display on the Lisp Machines? Actually, it was a series, IIRC - one for the CPU, one for the disk, etc. The machine didn't have LEDs, but it used short lines on the bit-map display instead. IIRC, the idea was copied from the Knight TV's on MIT-AI. (Which I believe were the first-ever bit-mapped displays - anyone know of an earlier one?) Noel

11 years

Info on Grid Systems 2260 Convertible Laptop/Tablet

by azd30＠telus.net

Hi, My search for any info on a Grid Systems 2260 Convertible Laptop/Tablet has so far been unsuccessful. I am looking for a user manual / repair manual / ads etc. Any help/pointers would be greatly appreciated. Also, if anyone has a power supply and/or accessories for this that they are willing to part with, please contact me off-list thanks -- alex

11 years

PDP-1 Replica for sale

by sellam＠vintagetech.com

I am selling off my last PDP-1 replica front panel. This is a fully functional replica PDP-1 front panel attached to the SIMH PDP-1 simulator running on a PC via a custom interface. It functions almost exactly like an actual PDP-1 front panel. You can deposit code/data from the front panel switches into the simulator memory, read it out by the same, and use the function switches to load virtual "paper tape". This is a fully assembled unit, ready for play. Comes with the simulator PC. Just add a monitor and you have yourself as close to a working PDP-1 as you're probably ever going to get. Photos/videos and other data available upon request. Ships from Livermore, California, or you pick up for free tutorial. Shipping costs should be no more than $60 for ground. Asking price is $3,800. -- Sellam ibn Abraham VintageTech ------------------------------------------------------------------------------ International Man of Intrigue and Danger http://www.vintagetech.com Whatsoever a man soweth, that shall he also reap. The truth is always simple. * * * NOTICE * * * Due to the insecure nature of the medium over which this message has been transmitted, no statement made in this writing may be considered reliable for any purpose either express or implied. The contents of this message are appropriate for entertainment and/or informational purposes only. The right of the people to be secure in their papers against unreasonable searches and seizures shall not be violated.

11 years

PDP 12 modes

by jnc＠mercury.lcs.mit.edu

From: Sherman Foy > Re: the 12, you were either in LINC mode or PDP mode at any given time. > These were NOT "parallel processors". I don't disagree. I was speaking of the LINC-8, which was a very different machine inside - it really was an 8 _and_ a LINC in a single box. The front console actually had a complete PDP-8 console _and_ a complete LINC console, side by side - two sets of lights, two sets of switches, etc. > I can't vouch for this on a LINC-8 machine, but I thought it was similar. Nope. Check out the manual I cited. Well, the LINC-8 and -12 might be similar (almost identical, probably) from the _programming_ point of view, but the hardware was organized totally differently (above). Noel

11 years

7030 simulation

by aek＠bitsavers.org

Dug back in my mailbox and Richard Cornwell was looking at this circa 2008-11. There was some work by JAM to OCR the listings. I don't remember if it was greenbar, and if the background was causing problems. The color scanner I use now does color dropout but it would be a PITA to rescan everything.

11 years

Reproducing old machines with newer technology

by jnc＠mercury.lcs.mit.edu

> From: Jay Jaeger > I am going to attempt to do the same for IBM's 1410 computer - a really > big effort. Now, the IBM machine you (or someone) should _really_ do is the IBM Stretch (7030); although judged a commercial failure at the time, in retrospect it's clearly one of the most ground-breaking designs of all time. (In fact, I have a hard time coming up with other machines with the same level of impact/influence, in terms of CPU internal architecture. Maybe Atlas, or the 801?) Noel

11 years

PDP 12 modes

by shermanfoy＠att.net

ATT has gone wierded out on attachments for the moment, so I'm dumping all this into a long text ramble Jim: Please forward these observations to the appropriate parties, copying me. I am having trouble sorting out who started the thread and who is receiving replies. I will respond directly to anyone w/ questions, to the best of my ability and experience. I believe that I see some discrepancies, as I think others are also questioning some assumptions. To: group I own and did operate a PDP-12; having written unique PDP-12 code, I disagree: the 2 modes "ping-ponged". I think some of the thoughts here are based on reading the books and thinking in "hardware mode" and not considering actual operation or the software implementations. I have done the full experience: ownership, hardware integration, commissioning, running and developing custom code of both PDP-12's and PDP-8's. I still own 1 PDP-12 and 4+ PDP-8's. Re: the 12, you were either in LINC mode or PDP mode at any given time. These were NOT "parallel processors". You called the LINC IOT instruction to switch from PDP mode to LINC mode; then you "returned" to PDP mode by making the PDP call in LINC code. Usually, you briefly switched to LINC mode to run the peripherals. Most of the code that you ran was PDP code. The TU-55/6's needed LINC code and so did the VR-12, for instance. It is possible that something written for the LINC would be run in LINC mode for high percentages of the time. That code might have some "patches" that ran in PDP mode after review and revision. It could be that such code was modified from LINC code to a PDP-12 routine using the 12 as a "development system" to test and implement such patches. The PDP-12 switch selected which mode you STARTED FROM, IIRC. Once you had launched and were running code, you had to switch via code calls in the routines. I can't vouch for this on a LINC-8 machine, but I thought it was similar. I wrote my own "Mag Tape Boot Loader" in my trials and tribulations while my 12 was running. The following is an excerpt from my account of that experience. Note the PDP versus LINC calls inline in the code. <quote> My Boot loader [MTBL] code used the followings syntax. It resided at the high end address of a page, was toggled in via Front Panel and a Front Panel "Start Switch" launched the code. It called the Mag Tape and rewrote itself over the corrupted memory. I think I had another routine to update the Mag Tape locations periodically, after rewrites. I can't remember the LINC syntax and would have to look those up in the reference manuals. (Don't leave the launch address without them.) Comments are posted after the code [in this case], to allow for inevitable corruption by non column friendly text machinery. ************************ * MAG TAPE BOOT LOADER * ************************ CLA LINC LIF 0 LDF 0 AXO RCG DATA PDP JMP I+1 DATA Comments, added here due to not being in "column mode" /MAG TAPE BOOT ROUTINE; /MUST BE PRESENT IN TAPE /BLOCK 273; WILL BE OVER- /WRITTEN ON USE. /WHEN CALLED THIS CODE READS /TAPE BLOCKS 270-273 TO /MEMORY BLOCKS 0-3. /TO USE: / 1) LEFT SW TO 1760 / 2) START LEFT SW /RESTART ADDRESS Sherman, 12 owner shermanfoy at att.net <endquote> The longer narrative in a Word doc is attached. A PDP-8 WILL NOT run LINC code: that is also by ownership & experience & hardware troubleshooting-debug & handwriting machine code. I did ALL of that in one session of working on a design flaw in the 8-E [also F & M] machines. Again, the PDP-12 does not run the two modes CONCURRENTLY, rather they run CONSECUTIVELY. I am borrowing the legalese for terms of sentencing, as it lends itself well to this description. And again, I am doing this from actual ownership and experience of getting hardware running, hand-coding and debugging custom routines. Of course, I did this after researching and reading instruction sets from the programming manuals and poring through sample code listings. Further, as I previously mentioned, I cannot vouch these thoughts and descriptions for the LINC-8. If I understand this correctly, the "straight LINC" would also share the use of LINC only code characteristic w/ the PDP-8's use of the PDP only code characteristic. My 12 is in storage and would be a "year out" to operation at any given time. That assumes that it has not suffered deterioration from its "put in storage running" status. It has always been stored in dry storage. Another major obstacle is simply finding the proper floorspace to mount its large footprint environmentally. If I am encouraged and/or flogged, I may bring the 12 machine out of retirement. I expect that my path will be to launch a PDP-8M [perhaps a PDP-8E] first and then bring the PDP-12's VR-12 out and try to interface it w/ an IBM PC. There is a local "moral imperative" to resurrect SpaceWars :) I also intend to try to make a TU-56HM STANDALONE Mag tape talk to the PC machine. The TU-56 Standalone mode is a rare beast and can be found in the FOOTNOTES on the TU-56 drawings. I do not believe there was a complete document for the Standalone machine. I seem to have the requisite TU-56 hardware, but I am not sure of the interfacing and cabling. Code would likely be written in C from a DOS environment on the PC. This would, likely be analogous to some of the TU-58 modes of operation, which were based on serial ports. I also have several pieces of TU-58, including a VT-103 machine. These projects could be described as ambitious. We need some more SoCal DECnutz. <quote> Then I discussed my 12 running time: The "12 monster" had Core Memory, which, like an elephant, doesn't forget. It had about 100 pounds of Sola Constant Voltage Transformer. These combos are good for brownouts. It had a Power Fail Auto Restart Option [PFAR, my acronym]. I learned the hard way on a PDP-11/44: don't screw with it and it will restore itself when the power come back. Also, the power supply had three gigantic electrolytics, about the size of thermos bottles. These guys were significant fractions of a Farad 40 YEARS BEFORE SUPERCAPS. The decay rate of the power supply was fantastic. This provided major "headroom" on the RC time constant that the PFAR used. One thing done with this was to turnoff the Write Amps for the Core Memory on Power Fail detection. All in all, blackout/brownout, the 12 was ready. I had a block level blackout happen and when the power came back on, restarted in "mid sentence" of the code I was bumming. I wrote my own version of a "Monitor", that I called MON-12. It was based on ODT-8. I originally keyed it in from the front panel, hundreds of lines. I wrote the documentation as I went. I stripped out the Paper Tape stuff, since the 12 didn't have one and I would have to add an extra cabinet; later??? The 12 had two TU-55's. Tape-tape copy was an obvious feature. But I always wondered why they didn't use a TU-56 Dual Transport and put a Paper Tape in the main cabinet. I have two TU-56's and a stack of PC-0X's patiently waiting in the warehouse. Somewhere along the way, I got to where I could edit from the keyboard. I also started work on an ambitious "block mode copy" function. If you can see this coming, I developed code that would "eat itself". After toggling this in from the Front Panel three times, I decided to take a cue from the Paper Tape stuff I had removed from ODT. I wrote a Mag Tape Boot Loader [MTBL, my acronym]. The 12 implementation for the Mag Tape used LINC code, not a TU-55 IOT set of calls. My Boot loader [MTBL] code used the followings syntax. It resided at the high end address of a page, was toggled in via Front Panel and a Front Panel "Start Switch" launched the code. It called the Mag Tape and rewrote itself over the corrupted memory. I think I had another routine to update the Mag Tape locations periodically, after rewrites. I can't remember the LINC syntax and would have to look those up in the reference manuals. (Don't leave the launch address without them.) Comments are posted after the code [in this case], to allow for inevitable corruption by non column friendly text machinery. ************************ * MAG TAPE BOOT LOADER * ************************ CLA LINC LIF 0 LDF 0 AXO RCG DATA PDP JMP I+1 DATA /MAG TAPE BOOT ROUTINE; /MUST BE PRESENT IN TAPE /BLOCK 273; WILL BE OVER- /WRITTEN ON USE. /WHEN CALLED THIS CODE READS /TAPE BLOCKS 270-273 TO /MEMORY BLOCKS 0-3. /TO USE: / 1) LEFT SW TO 1760 / 2) START LEFT SW /RESTART ADDRESS Sherman, 12 owner shermanfoy at att.net <endquote>

11 years

Data General Kit on Ebay

by dave＠willomail.co.uk

Not mine but could be interesting for anybody local... http://www.ebay.com/itm/Trailer-full-of-Data-Genereral-computer-equipment-G… Cheers, Dave

11 years

PDP-11 pages/segments/etc (Was: PDP-12 at the RICM)

by jnc＠mercury.lcs.mit.edu

> On Jul 13, 2015, at 8:52 PM, Johnny Billquist <bqt at update.uu.se> wrote: > ??? What segments??? The PDP-11 have a plain simple page table. No > segments anywhere in sight. And each page is 8K. I know the processor handbook calls them 'pages', but I can't think of any other machine where pages are variable size. (I know of a couple which offer _two_ page sizes, but none that have a field per page which specifies the length of the page.) They really are more like what most machines call 'segments'. I know Unix doesn't use them that way (because it has such a simple-minded memory model), but other systems do - e.g. MERT. Noel

11 years

FS: Apple IIGS, C64, Intel OpenStep Boxes, DOS Gaming rigs & more

by slandon110＠gmail.com

Clearing out more of the collection that never gets used- everything works perfectly and is cosmetically in good condition. Prices are make an offer, i just want to see this stuff go to a good home Apple IIGS ROM 03 4MB RAM Card CFFA 3000 Card 2x 3.5inch FDDs 1x 5.25inch FDD AE Conserver- Allows you to sit 2 Floppy drives under the monitor and functions as a power strip Commodore 64 C64NIC+ ZoomFloppy SD2IEC Interface with 8GB SD Card JiffyDOS Cart Slot Expander from Jim Brain 1701 Monitor 2x 1541 FDDs Mac Performa 631CD 64MB RAM 500MB HDD Ethernet Card Matching 15inch Monitor NeXT Mono Slab 20MB RAM 2GB HDD Frog Monitor Non ADB Keyboard & Mouse HP 9000/712 96MB RAM 1GB HDD NeXTSTEP 3.3 Installed Sun SparcStation 5 64MB RAM 36GB HDD OpenStep 4.2 Installed 3 Intel OpenStep 4.2 Boxes Dell Dimension XPS T450 128MB RAM 10GB HDD Rage 3D Video SoundBlaster Awe32 USB Card- Supported in OpenStep 4.2 Dell Dimension 233mhz 32MB RAM 4GB HDD Networking OpenStep 4.2 Installed Needs SB 16 Card for Audio HP Pavilion 6630 Celeron 500mhz 64MB RAM 3C905 Network Card Running OpenStep 4.2 Needs SB 16 Card for Audio DOS/Win Gaming Rigs Dell Dimension L1000R Windows 98SE 256MB RAM 20GB HDD Rage 128 Video Dell Dimension L667R 128MB RAM 15GB HDD Rage 128 Video. IBM AT Clone 40MB HDD 640K RAM 5.25 and 3.5 Drives Parts & Stuff 10 36GB SCA SCSI Hard Drives Sun Caddy Load external SCSI CD-ROM Sony External SCSI CD-ROM 4x Zip Drives, 2 Parallel 2 SCSI with 20 zip disks Syquest EZ135 Drive with 15 Carts Medium Flat rate boxes filled with DSDD 3.5inch Disks 5.25inch Disks and 3.5in HD Disks 6 Large totes filled with SCSI Cables, AC Adapters, Ethernet Cables, You name it There is honestly too much to list.. Thats just a sampling of whats here in parts and accessories. Thanks Steve

11 years

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