On 4/9/24 22:03, ben via cctalk wrote: What model of a 360? 8K sounds a lot like a Model 20, which the purists may not consider to be a "real" member of the family. --Chuck

A 360 front panel sold for over $4,000 I think much more on eBay recently I can't believe it I cannot believe it Sent from AOL on Android On Tue, Apr 9, 2024 at 11:46 PM, Adrian Godwin via cctalk&lt;cctalk(a)classiccmp.org&gt; wrote: And the 'tarpit' book is 50, dated by the preface. On Wed, Apr 10, 2024 at 6:22 AM Chuck Guzis via cctalk < cctalk(a)classiccmp.org&gt; wrote:

On Wed, 2024-04-10 at 03:45 -0500, CAREY SCHUG via cctalk wrote: After loading the Compatibility Initialization Deck or CID, a 1401 program could be run from cards by putting 1402 into the IPA dials, or from tape by putting 1729 into the IPA dials, and pushing IPL. The IPA was, IIRC, the address in the microcode.

On Wed, 2024-04-10 at 23:52 -0500, CAREY SCHUG wrote: My boss in my first full-time job had worked at a bank in Dayton, OH. They had an NCR 315, with a device called CRAM, or Card Random Access Machine. That machine used cards the same size as punch cards, but made of mylar and coated with mag-tape oxide. It had a compressed-air-driven mechanism to extract a particular card from a file, drag it through some read-write heads, and put it back. They loved the CRAM sort routines. The machine made a hell of a racket, so they had it in a sound-proof room. An IBM salesman convinced them to try out a 360/30 with a Data Cell. After a month, the salesman came back and noticed the Data Cell in the same sound-proof room as the CRAM. He asked "Why is it in there? It doesn't make any noise!" The answer was "We hope it will learn some software."

Yes. See also https://en.wikipedia.org/wiki/IBM_2321_Data_Cell . By the standards of the time it was an unusually high capacity storage device, way faster than a room full of tapes and much larger than the 2311 disk drive. paul

I suppose. Or magnetic cards. There were other devices that used magnetic cards, like the Olivetti Programma -- world's first programmable calculator. For that matter, magnetic cards are still around, they are called credit cards. :-) paul

On 4/12/24 11:10, Tom Gardner via cctalk wrote: problems too and in the end I'm told it was a rather successful product. I recall a friend whose shop used the CRAM remarking that a cardboard box needed to be kept near the machine. Apparently if card was rejected for some reason, it was simply spat out to the floor. --Chuck

When I said "addressed as disk drives (DASD)" I was referring to IBM's DASD's (Direct Access Storage Device's) CKD (Count Key Data) format introduced with the System/360 which supported variable length records, or as Paul calls them "variable length sectors" on disk drives, data cells and drums amongst other devices. The Count field of each Record defined the length of both the optional Key field the Data field so that on a single track you could have records of different length - not likely but possible. It was also possible to write a record longer than a track using record overflow. Variable length CKD records are still supported today in IBM's mainframe systems by emulation on arrays of fixed sector HDDs. Tom -----Original Message----- From: Paul Koning &lt;paulkoning(a)comcast.net&gt; Sent: Friday, April 12, 2024 12:13 PM To: t.gardner(a)computer.org; cctalk(a)classiccmp.org Cc: Tom Gardner &lt;tom94022(a)comcast.net&gt; Subject: Re: [cctalk] IBM 360 &lt;cctalk(a)classiccmp.org&gt; wrote: Actually, they look like a disk. See the 2841 manual on Bitsavers (that's the controller which drives 2311 disks as well as 2321 data cell devices). It says that each strip has 100 tracks, read/written by a movable heads unit that has 20 heads on it, so 5 positions. And it shows the layout of each track, which is the conventions count/key/data layout of 360 disk drives like the 2311. Yes, variable length "sectors", you'd specify in the JCL what you wanted for blocksize of that particular file. If I remember right, the block length could vary from one block to the next, which is pretty wild. (Contrast with the EL-X8 disk drive, which also has variable length sectors, but more limited: a choice of one of 5 possible sizes, chosen on a per-track basis when you first write or format that track.) Apart from those, I only ever remember seeing fixed size sectors, though the actual lengths might be strange -- like the CDC mainframe disks with sectors of 322 12-bit words. paul

No worse than automatic tape loaders that push a long strip of tape trough various feeds and onto a takeup reel where it is made to stick. at least each of these strips had a handle on it. In later years all serious computer tape drives had autoloaders, and I think a few for high end consumer tape recorders. <pre>--Carey</pre>

On 4/12/24 09:45, Christian Kennedy via cctalk wrote: Isn't that the IBM 2321 Data Cell drive? Having one's files "photostored" at LLL was a chancy proposition. There were bootleg programs to access every file for a user, just to keep them from being consigned to the photostore. --Chuck

On 2024-04-12 2:45 p.m., Christian Kennedy via cctalk wrote: The problem with a lot of these old machines was they relied on a lot of electro-mechanical  devices that would today be replaced by electronics and a few simple actuators.  These mechanical devices need to be adjusted and maintained  and have lots of parts to wear out.  While I only started with IBM in 1979 I still got to work on machines that would now be considered electro-mechanical nightmares. The development of the 2321 (announced 1967?) was long and apparently had to overcome a lot of problems, but they apparently soldiered on with it as it was considered a strategic product all for 400,000,000 characters of storage.  The later 3850 (announce 1974) MSS had  much simpler cartridge retrieval system and had storage capacity up to 472 GB.  The capacity of these seems tiny these days but given disk storage at the time, it would take a lot of DASD devices to equal that and the expense would be enormous if you could even fit that many within the reach of channel cables from the system.  Late in the days of copper channels one data center I knew of was spread over three floors, with the CPU on the middle floor and channel attached devices  surrounding it and as far a channel cables could reach on the floors above and below. The 1360 was apparently developed at the request to Atomic Energy Commission (AEC), I  would guess a forerunner of the DOE.   There where apparently only 5 built 3 for the AEC and 2 for the NSA. Paul.

Some of the earliest magnetic storage was mechanically simple: magnetic drums. Nothing moving apart from the spinning media, and quite fast. Fixed head ("head per track") disk drives are a variation on that theme, DEC had some that were successful for a while. I remember a concept for a very fast magnetic storage system that didn't become a product, as far as I know. The scheme was to build a large array of heads, using IC-manufacturing type techniques, and mount that array in contact or near-contact with a flat rectangular magnetic plate. The plate (or the heads) could move a small amount in one direction. The idea was "head per sector", with the mechanical motion scanning the sector across the head. Given something like piezo-electric actuators it would have been quite fast. There's a neat document in the CWI archives, a course on computer design from early 1948. It has a section about memories, well before core memory was invented. The schemes it describes are quite curious, including photographic memories, selectrons, and various other schemes. Also drum memories, including the rather mythical notion of a drum spinning at 60,000 rpm. paul

Yes, the Univac Model I acoustic delay line memories. The document I mentioned is MC report CR-3, by A. van Wijngaarden, 1948, which is online in their archive but only as a not particularly clear scanned document in Dutch. It describes six memory technologies: photographic film, fluorescence, electric resistance (including the notion of a neon cross-bar, which is another way of describing Bitzer's inherent-memory plasma display panel but more than a decade earlier), acoustic waves (such as the Univac memory), magnetic tape, wire, or drum storage, and electrostatic charges (the Selectron is described in detail). Not all that fast, well, it depends on what you're comparing with. Given tube logic with cycle times measures in microseconds, quite possibly serial rather than parallel organization, those acoustic or drum memory systems weren't all that terrible. paul

On 4/12/24 14:27, Van Snyder via cctalk wrote: One that comes to mind is the Datatron/Burroughs B-205, used as a prop in several Hollywood productions (or at least pieces of one).. The drum there was divided into two areas; the "main storage" area where each track stored 100 words of 11 digit BCD and the "quick access" tracks that stored only a tenth as much, 20 words. The deal was that writing a word to the quick access tracks would write it 10 times, so that access time to a word was cut by 90%. Clever. --Chuck

Different beast, but it reminds me of an electrostatic plotter we at on the U of Illinois PLATO system. That one was by Versatec, either 11 or 17 inches wide (I forgot), 300 dpi, pretty sure it used wet toner. It also used a chain drive for the paper feed, which had enough backlash that starting and stopping would produce visible irregularities in the output. So I wrote a driver for it that did overlapped I/O to avoid that problem. (File I/O directly from a PPU program, lots of fun!) With that, it did an awesome job printing musical scores. paul

On Sat, Apr 13, 2024 at 10:48 PM Jon Elson via cctalk &lt;cctalk(a)classiccmp.org&gt; wrote: Does anyone else have one in their collection? I have an ICL-badged V80 which has a GPIB interface to link it to a PERQ. I also have the schematics, etc for the plain V80 but nothing on the GPIB interface (ether user or service data). IIRC the V80 is based round a Texas 16-bit microprocessor with some AM2900-series sequencers and ROMs to control the electrode timing. As Jon said in the bit I deleted, there's a 'nib electrode' under the paper and a segmented backing electrode above it. The charge image is built up on the paper, then the toner is flowed over it and the carbon (I assume) particles adhere to the charged bits. No drying heater in mine. -tony

It wasn't just Versatec plotters that used this mixture - standard office photocopiers also had clay-coated paper and liquid toner. I don't know what allowed the change to plain-paper copiers (which use an intermediate photosensitive drum, like a laser printer) but it was probably the expiry of a patent, maybe Xerox's. On Sun, Apr 14, 2024 at 8:02 AM Paul Anderson via cctalk < cctalk(a)classiccmp.org&gt; wrote:

Indeed. Meanwhile, it turns out my memory was faulty. The printer I was describing sounds a lot like the Versatec ones you mentioned, including the funny paper and smelly toner. But it was actually made by Varian, and the driver tells me it had 1408 pixels across the width of the paper, so at 11 inches wide that would make it 128 PPI. I wonder if I still have a sample page or two from that printer. paul

I remember a Varian computer sitting in a corner of a lab at U of Illinois (computer science department). It looks similar to the ones shown in Bitsavers but not quite the same -- it had a front panel that had mostly brown coloring, and the panel was totally flat. It used membrane pushbuttons for operation, with the button positions marked by circles on the flat plastic front panel. Does that ring any bells? I remember being told it had user programmable microcode, but I never used it, in fact I never heard of anyone using it. paul

The tape for the Burroughs 220 drives was not metallic. It was 3/4-inch wide, and I think a Mylar sandwich. It could be spliced much the same way you would have spliced quarter-inch reel-to-reel audio tape back in the day. If the tape controller detected a parity error, it would backspace the block and retry twice. If the error persisted on the second retry, the tape would stop with the head ready to read the bad block (hanging the processor in the middle of its I/O instruction), and the operator would have to take manual action. If the drive punched a hole in the tape, then the drive needed service -- probably a bad capstan pinch-roller solenoid.

The main storage area of the ElectroData/Burroughs Datatron 205 was 20 tracks of 200 words each for a total of 4000 words. The drum rotated at 3570 RPM, so the average access time was about 8.4ms. The four quick-access tracks (or "loops" as they were called) were 20 words each and worked as a delay line, much like the Bendix G-15's drum. These tracks had separate read and write heads. When writing was not taking place, the digits from the read head were simply copied to the write head 36 degrees behind on the surface of the drum. So as the last digit of the track was written, the first digit of the track was coming under the read head, yielding an average access time of 0.84ms. When writing, digits from the processor were shunted to the write head in lieu of those coming from the read head. When power was removed from the system, the 4000-word main memory was preserved, but the data in the high-speed bands was lost. The 205 had instructions to transfer 20-word blocks between the main memory and the high-speed tracks. There were even a couple of instructions to move a block to one of the high-speed tracks and branch to a word in that high-speed track. The high-speed tracks were addressed modulo 20 (i.e., word 4005 was the same as 4025, 4045, 4065, ... 4985). You had to get good at dealing with addresses that were congruent modulo 20. The high-speed tracks were so much faster than main storage that most programmers went to a lot of effort to "block" 20-word segments of the program to the high-speed tracks and execute at least the most active code from the faster storage.

The United States Atomic Energy Commission was superseded by the Nuclear Regulatory Commission in the 1970s. The Department of Energy is not the same thing at all. Rich

On 2024-04-12 7:09 p.m., Rich Alderson via cctalk wrote: The Wikipedia article on Department of Energy (DOE) suggests that in 1974 the Atomic Energy Commission (AEC) was split into two organizations the Nuclear Regulatory Commision (NRC) and the other for energy research and development and I believe this is what is now known as the DOE.  I book I found information on the IBM 1360 indicates 3 where sold to the AEC and one was installed at Livermore and another at Los Alamos both of which I am pretty sure are DOE facilities now.  So it would seem that the AEC was the ancestor for both the DOE and the NRC. Paul.

On 4/12/24 14:54, CAREY SCHUG via cctalk wrote: The beer-can-in-a-beehive 3850 MSS, perhaps? At a trade show where the thing was being demonstrated (NCC perhaps?), I remember the presenter saying that the advantage of two "picker" assemblies was that one could push the other out of the way should it stop working. MPI/CDC did offer a competing product, but I don't recall the number. --Chuck

On 2024-04-12 7:23 p.m., Paul Koning via cctalk wrote: But too slow I suspect to run a game like spacewar.

On 4/13/24 12:20, Paul Koning via cctalk wrote: I cannot count how many hours I spend on the Plato IV terminal at our local university playing Empire and Dogfight - I was in high school at the time... --tom

Plato experience is still active including the games at https://www.cyber1.org/ Regards, Tarek Hoteit AI Consultant, PhD +1 360-838-3675 https://tarek.computer INFOCOM AI LLC - https://infocom.ai

On Fri, Apr 12, 2024 at 6:55 PM ben via cctalk &lt;cctalk(a)classiccmp.org&gt; wrote: I never got to use it but I used to own one. A Mohawk Data Sciences unit. Sellam

On Sat, 2024-04-13 at 07:58 +0100, Dave Wade G4UGM via cctalk wrote: As a freshman, I noticed that the HP Digital Slide Rule 6-digit pocket calculator was only $600. I suggested to myy college buddy Ed Kelm that it ought to be possible to build a desk calculator that used a TV for the display. That never happened, but Ed held onto that thought and eventually designed the Lexitron dedicated-logic word processor. It had a landscape-format screen. Vertical scrolling was done by typewriter- platen-like knobs on both sides of the screen. Margins were set by the same kinds of sliders as on a typewriter. As you can imagine, training for experienced secretaries was less than half a day. Documents were stored on 1/4" three-track tape cassettes using a drive invented by another school-days chum named Cliff Tedder. Because of problems with the Orange County, California, power system, where voltage ranges of 90-130 volts were common, Ed invented the now well-kinown switching power supply -- and Lexitron kept the patents so Ed got nothing but a salary from it. It rectified line voltage, regulated it to 90 volts, which ran a 20 kHz oscillator (so that the transformers required far less iron), and ultimately produced well-regulated power for the electronics. Raytheon bought Lexitron, and pounded it into the ground. Ed ultimately took his instance of it to a landfill because he couldn't find a computer museum that wanted it.

My wife did, sort of: for a while she worked with IBM MT/ST word processors. Those were very early word processing systems that used a custom magnetic tape cartridge for storage and a Selectric typewriter for I/O. paul

On 4/13/24 11:22, Michael Thompson via cctalk wrote: The mag card Selectric (MC/ST) was relatively popular also. --Chuck

Memories are fuzzy. I think I remember a device that wrote to a magnetic tape, where the tape written to just fell into...something like a very wide vacuum column from a tape drive, not taken up on a spool. Maybe it had a keyboard, but it's input actually came in over (dial-up?) tty-like serial data. Like, branch offices or field sales people called in and upload their daily data? Does anybody remember anything like this? --Carey

On Sat, 13 Apr 2024, Paul Koning via cctalk wrote: Rather off-topic, and silly (about MT/ST), . . . I gave away one decades ago. A friend wanted it as an advertising prop because he was writing a word processing program called "FULL/ST".

On 4/12/24 20:55, ben via cctalk wrote: I bought a surplus desktop key to tape machine made by Pertec.  It had a 7" 9-track drive in it, a small core memory and a field of light bulbs to show the read-back contents, as well as the keyboard.  I tore it apart at the right section and turned it into a mag tape drive for my Z-80 CP/M system.  The basic tape formatting was all done in software, and I took tapes in to work and read them on our VAX to verify what I was doing was readable. I also traded a guy for a Honeywell key to tape system that apparently was used as an off-line tape to line printer unit.  But, it was actually possible to use it as a key to tape machine, too.  I wanted it for the 300 LPM printer, but had to use it in the tape to print mode to decipher the protocol of the printer. Jon

On Fri, Apr 12, 2024 at 9:45 AM Christian Kennedy via cctalk &lt;cctalk(a)classiccmp.org&gt; wrote: Nowhere near as cool, . . . About 30 years ago? (When libraries would DEDICATE a PC for each CDROM that they had) Keith Hensen made a device consisting of a carousel holding 240 CD/CD-ROM/DVDs. It had a name something like "Qubik"? It was in a square box with a smoked plexiglass cover, with a drive at each corner. They were stackable. The drives were SCSI, the carousel controls were RS232. -- Grumpy Ol' Fred cisin(a)xenosoft.com

On Tue, 2024-04-09 at 22:21 -0700, Chuck Guzis via cctalk wrote: I don't remember whether it was one of the docents at Haus zur Geschichte der IBM Datenverarbeitung at Sindelfingen, or at the Computer History Museum at Mountain View, who told me that IBM was developing a machine to be designated 1480, as part of the 1401-1440- 1460-1410 series, with newer technology, roughly contemporaneously with the 360. When IBM decided to put all its eggs in the 360 basket, The 1480 team somehow survived and produced either the 360/20 or 360/25. An 8k machine would be a bit weird in this series, since 1410 was already 100k. Does anybody know more details about this? Samir Husson wrote a book about the 360/30 that described the microcode. Has anybody built a 360/30 from FPGA? Does anybody have the 360 and 1401 microcode for it? How about the Compatibility Initialization Deck to run the 1401 microcode emulation?

On 4/10/24 01:51, Van Snyder via cctalk wrote: The 360/20 had only halfword instructions, no float, no char strings.  But, main storage was 16 bits wide. The 360/30 only had byte-wide memory, and the register file was in a separately addressed part of main storage.  The 360/25 was a very interesting concept.  The microcode was in the top 16 KB of main storage, and 360 and other instruction set emulations could be loaded from cards.  The boot loader for the emulators was in the top 16 bytes (or maybe words) of main storage. Jon

On 4/10/24 11:19, Chuck Guzis via cctalk wrote: OK, never worked on one, I did actually see one in a tour once. So, there's a lot I don't know about the /20.  Thanks for the correction. Jon

Yes, 1964, amazing. I remember, I must have some vintage IBM training/instruction materials on the 360, 704 and FORTRAN programming systems. This came from a long time computer professor who took these courses in the early 1960s, Dr. William (Bill) M. Myers (University of Montana) It's a massive binder and contains hundreds of pages of official IBM information, charts, brochures and notes. In very good condition, and with original training documents for Northrop Aircraft Inc. in 1966. see: https://drive.google.com/drive/folders/1AwfIo3_FrdkRsD4Qz3X8aiNAdm1D1buj?us… It also shows a full IBM system introduction handbook and Quick Reference manual form 1964. Check out the Northrop News-Venture Edition 1966 Northrop Aircraft Inc. article on installation of an IBM360/64 system, where the training took place. As I 'm not so much into the System/360 and FORTRAN IV, if anyone is interested, please let me know. Thomas On 10.04.2024 16:17, Jon Elson via cctalk wrote:

On Wed, 2024-04-10 at 21:28 +0100, osi.superboard via cctalk wrote: When I was a freshman at Caltech, 1964-65, IBM installed a 360 model 63, I think one of only two ever made. After they finished installation, they executed the "Halt and Catch Fire" instruction, then replaced it with a 360/67. I kept using the 7094 until I left during my sophomore year because computer science was dead at Caltech for (at least) ten years after Don Knuth moved to Stanford. I think the 360/67 replaced "Halt and Catch Fire" with "Rewind and Break Tape."

I want to thank you all for this IBM 360 conversation.  It makes me feel young🙂.  My first computer was a PDP-8/L with 4K of core memory and a Teletype ASR-33.  That was 1972 (I was 12). On 4/10/2024 4:23 PM, Paul Koning via cctalk wrote:

Mike, Hi. My first "computer" was a PDP-8/I with 4k core, high speed reader/punch and an ASR-33 TTY that was in the early 1970's. I got it used from a lab that was closing for $600.00 delivered. Eventually expanded it to 12k core with 2 DEC tape drives. Loads of fun. DECus came in handy. Ken Martin On Wed, Apr 10, 2024 at 5:40 PM Mike Katz via cctalk &lt;cctalk(a)classiccmp.org&gt; wrote: -- End of line JOB TERMINATED

On 2024-04-10 2:21 a.m., Chuck Guzis via cctalk wrote: The IBM Don Mills plant in Toronto built model 20s.  I knew guys who bought their houses with the overtime working on them.  They had accumulated a lot of engineering changes that had not been cut into production, so they would be assembled and then there where teams that would apply the engineering changes before the systems where shipped. Paul.

I remember that building well!   My only visit there was at 2 am though!  I had a 6250bpi GCR mag tape and my drive only did 1600, so a friend who worked there took it from me and converted  it. I thought I would be interrogated by the guard, but apparently small-hours deliveries were commonplace! Funny though, now my friend denies it was him :-) cheers, Nigel On 2024-04-10 09:35, Murray McCullough via cctalk wrote: -- Nigel Johnson, MSc., MIEEE, MCSE VE3ID/G4AJQ/VA3MCU Amateur Radio, the origin of the open-source concept! Skype: TILBURY2591

One interesting historic tidbit is the Dutch connection on the IBM/360. One of the lead designers on the 360 was Gerrit Blaauw, a Dutch computer engineer who learned his craft at Harvard (with Aiken), and refined it at the MC in Amsterdam (now CWI) leading the design of several one-off research computers. Among other things, he taught the other designers that logic needs to be clocked to be reliable. :-) After that, he left for IBM and worked on several computer designs, culminating in the 360. Wikipedia says that the choice of 8 bit characters rather than the then-current 6 bits came from him. paul

>Just 7 year old and no longer in service.>Anyone with some space in the basement ?But will it run Doom?

On 5/3/24 09:35, Adrian Godwin via cctalk wrote: I saw that someone posted on Twitter that they repurposed a disposable home pregnancy test stick display and parts to run it. Apparently it wasn't enough (isn't?) to have lines on the stick you need to have it have a fairly capable display.  And it's disposable.  Unless you're a tinkerer.

On 4/10/24 00:21, Chuck Guzis via cctalk wrote: Yup, the /20 should have been called a System 180, as it was about half of a 360 instruction set.  But, it only had 4 registers. Jon

Nearly all the 360s were microcoded, so adding a bit more microcode let them emulate 1400/7000 series computers as a standard optional feature. (well the model 44 emulated the 1620, and probably the 95/195 could not emulate anything since they were hard wired). I do not recall that was documented in the Principles of Operation. Does anybody here know how emulation was turned on (and off)? was there some special bit or bits in the PSW, or an undocumented instruction? --Carey

On 4/10/24 07:18, CAREY SCHUG via cctalk wrote: The model 44 was not microcoded.  It had faster floating point than a model /50 but no decimal or string instructions.  Emulation of these was done through trap handlers.  I would assume any other machine emulators were done by something like an emulation wrapper program - like Virtualbox or VMware.  The model 44 had no channels, there was only direct I/O (a set of 32-bit parallel input and output registers) and a pair of cartridge hard drives inside the CPU cabinet.  Think DEC RK05s. Jon

No channels? That doesn't sound right. The 360/44 I used certain had an RK05-like drive in the CPU cabinet (I only remember one, though). I'm fairly sure it was a 16-sector pack, so more like an RK08. But the system ran both OS/360 and TSO, and had three 2311 disk drives, three tape drives (with an amazingly ugly mechanical design), a card reader/punch, and a line printer. Also some sort of terminal max, but I never used the timesharing feature so I don't know what that involved. It certainly had enough of a channel-like I/O system that the emulator program loader could be implemented in a card reader channel program no different from that of other 360s. I remember quite well deciphering it using the CCW documentation on the "green card". Yes, the emuation of SS instructions was via traps, but specifically by a trap into emulator mode in a separate chunk of memory not visible to the main OS. I never saw the cartridge drive in use by anyone. paul

I don't know if it was an option. If so, presumably it was included if you elected the emulator option, since both are intended for running OS/360. paul