#Tag
I should add that I've done all of this using the s709 emulator from David Pitts (https://cozx.com/dpitts/ibm7090.html), using the eliza-ctss distribution from Rupert Lane (https://timereshared.com/). I'm sure both of these projects involved a massive amount of work, for which I'm incredibly grateful.
#retrocomputing #ibm #mainframes
4/4
Here's what's actually involved in doing a DSKEDT run (once CTSS is shut down and the CPU is halted):
1. Mount the DSKEDT tape (in drive A1 by default, at least in the emulator).
2. Execute 'load tape'. I believe this might have been a physical button on a real machine, which loaded the contents of the tape into memory.
3. Set the accumulator to be "CTSS ". I don't really know why you need this, but you seem to.
Next up is toggling the sense switches. I think you have three options: all down = start with REQUEST FILES, sw1 up = read cards and sw4 up = read the data which would be on the cards from tape A2. I actually used the sw4 version, having first mounted the tape.
Once you've done this you can hit start. The program will say it's started the tape drive, and halt. Then to continue:
4. Set sw4 down.
5. Hit start again. The system will process the jobs and then halt again.
6. Set sw2 up.
7. Hit start. The system will print 'EXIT CALLED' and you can shut down the emulator.
This process is really fussy, and it's super easy to get it to crash badly enough to require you to run a recovery program before you'll be able to try again (I think due to inconsistent state information for the DSKEDT program, not wider filesystem corruption). Many of the prompts output by the program are hard to make sense of, or seem to tell you to do the opposite of what you really need to do.
#retrocomputing #ibm #mainframes
3/n
Every now and then (the documentation seems deliberately vague about this, but says 'several times a day') a 'disk edit' program was run by the admin staff. This must have evolved over time - the earlier documentation refers to separate 'load' and 'dump' programs, and seems to have dumped the hard disk to tape backups and then reconstructed it every time (maybe from a time when the computer wasn't exclusively used for CTSS). The version I have is a single program, and I don't think it rebuild's the disk at all - it just executes the jobs in the queue - reading from REQUEST files and the card reader.
I loaded the MUSIC.FAP cards offline, i.e. I shut down CTSS, booted from the DSKEDT tape, and restarted CTSS once all jobs had been processed. The documentation does refer to it as 'background task', so I suspect there may have been a way of doing it without having to shut down the OS first.
A couple of things about old mainframes which seem unusual today. The first is that halting the processor is a thing - code is written to trigger a halt, the user then loads a tape, or flicks some switches, or something, and then presses a start button to get the CPU to continue. I suspect this stopped happening once you had time sharing up and running, but it crops up when administering CTSS. Secondly, you have sense switches and lights - these are literally a bank of toggle switches and lights which can be read or written to in code. The switches are used for configuration - presumably because if you're writing machine code by hand it's easier to use the built in 'jump if sense switch set' operation than it is to write a parser for a configuration file.
#retrocomputing #ibm #mainframes
2/n
Let me add a bit more detail on how this works. The #ibm7094 (specifically the one in the #MIT Computation Center which ran #CTSS) had a hard disk which was used for working storage. My understanding is that the preferred way of working was for users to enter files directly into the system via a teletype terminal, but the system did also have a card reader and multiple magnetic tape drives.
I don't think CTSS provided a friendly way for users to initiate loading from cards (although I'm not sure what there really was in the way of access control for the hardware if you were willing to write your own code). I suspect you wouldn't have had physical access anyway, so you would have had to have worked through the admin staff.
In practice, you would have done this by submitting a job. Jobs covered various I/O tasks, e.g. bulk printing, and for the most part could be submitted through an OS command (which wrote to a special file in the user's home directory). The one exception to this was card input, as that required the physical cards to be submitted to a helpdesk. Those cards were bookended by a metadata card (specifying the user and output filename) at the start and an EOF card at the end. In theory all of the job types could be submitted in the same way - except the 'deck' in those cases would just be the metadata card (and in fact the REQUEST in the users home directory was just an online representation of the same cards).
#retrocomputing #ibm #mainframes
1/n
My website and continuing mission for #IBM, #Lexmark, #Unicomp, #Lenovo and #TGCS #keyboard excellence has reached its sixth year! Like most past years, I have written this post to go over everything we achieved since September 2024 and to give my thanks! https://sharktastica.co.uk/announcements/202509A
My website and continuing mission for #IBM, #Lexmark, #Unicomp, #Lenovo and #TGCS #keyboard excellence has reached its sixth year! Like most past years, I have written this post to go over everything we achieved since September 2024 and to give my thanks! https://sharktastica.co.uk/announcements/202509A
We have made Microsoft’s commitments on Teams legally binding under EU antitrust rules.
Microsoft will unbundle Teams at lower prices, boost interoperability and data portability.
This means more choice for users, and fair competition ensured in Europe.
Why painting their greed with a "fair" (out)look if IT's everything but fair #software, #opensource or #FOSS?
You
@EUCommission could lead by example and recommend @jitsimeetinstances , but promoting their #surveillancecapitalism solutions might be a boomerang. Don't you think?
Btw. Mugshot of #BillGates the 3rd on a bluescreen with #IBM PC5150 standing on shoulders of #DigitalResearch is a #vector #illustration made with #Inkscape, not #Adobe#Illustrator
Huge culture change at #IBM was when they started wearing Polo shorts...
... Everyone was wearing Polo shirts so it became the new uniform
🙄
Other anecdotes:
1) IBM managers realized that programmers were just sitting there typing on keyboards, and getting paid a lot more than typists, for ( what they thought ) was a similar, slightly more technical job. So IBM starts firing programmers and replacing them with typists, with some training thrown in.
2) Airconditioning failed at an IBM office and programmers had to seek management approval to take off the ties ( they all wore business suits ).
Huge culture change at #IBM was when they started wearing Polo shorts...
... Everyone was wearing Polo shirts so it became the new uniform
🙄
Just in case you don't already have a million good reasons to avoid giving BorgSoft money, or eating any pie they've had their filthy fingers in ...
"Israel relying on Microsoft cloud for expansive surveillance of Palestinians"
#HarryDavies, #YuvalAbraham, 2025
... they're also the IBM of the 21st century, providing computer systems that help fascists do ethnic profiling more efficiently. Making them accessory to genocide
Just in case you don't already have a million good reasons to avoid giving BorgSoft money, or eating any pie they've had their filthy fingers in ...
"Israel relying on Microsoft cloud for expansive surveillance of Palestinians"
#HarryDavies, #YuvalAbraham, 2025
... they're also the IBM of the 21st century, providing computer systems that help fascists do ethnic profiling more efficiently. Making them accessory to genocide
Finally, the separate box of POWER9 upgrades appears. These are for the dual socket 144 thread Talos II here at home (the LC-922 are in colo). Relocation has turned up a lot of missing hardware, very pleased about this turn of events.
So, the long lost box contains:
- 4x Samsung 883-DCT 2TB SSDs for local storage ZFS pool (with 2x Optane NVMe cache)
- 3x PM863a 240GB SSDs for the OS
- always more RAM
- an OcuLink 4x to U.2 cable w/ Optane drive floating around somewhere
- Mellanox 50GbE QSFP28 NIC for RDMA fun
@dexter finally, we can continue the project with appropriate hardware
#homelab #power9 #ibm #freebsd #goodmorning #unpacking #servers #hardware #happiness
Finally, the separate box of POWER9 upgrades appears. These are for the dual socket 144 thread Talos II here at home (the LC-922 are in colo). Relocation has turned up a lot of missing hardware, very pleased about this turn of events.
So, the long lost box contains:
- 4x Samsung 883-DCT 2TB SSDs for local storage ZFS pool (with 2x Optane NVMe cache)
- 3x PM863a 240GB SSDs for the OS
- always more RAM
- an OcuLink 4x to U.2 cable w/ Optane drive floating around somewhere
- Mellanox 50GbE QSFP28 NIC for RDMA fun
@dexter finally, we can continue the project with appropriate hardware
#homelab #power9 #ibm #freebsd #goodmorning #unpacking #servers #hardware #happiness
"If you bought a ThinkPad between 1995 and 2017, it was probably designed under the oversight of David W. Hill, who served as lead designer under both IBM and Lenovo for those 22 years. We caught up with Hill, who today runs his own firm, ThinkNext Design, to talk about the history of ThinkPad, what drove him to make key design decisions, and the products he wanted to come out with but just couldn't."
https://www.theregister.com/2025/08/02/thinkpad_david_hill_interview/
"If you bought a ThinkPad between 1995 and 2017, it was probably designed under the oversight of David W. Hill, who served as lead designer under both IBM and Lenovo for those 22 years. We caught up with Hill, who today runs his own firm, ThinkNext Design, to talk about the history of ThinkPad, what drove him to make key design decisions, and the products he wanted to come out with but just couldn't."
https://www.theregister.com/2025/08/02/thinkpad_david_hill_interview/
Great infographic of companies involved in the genocide of Palestinians. Taken from this article, which also has more information on each: https://www.aljazeera.com/news/2025/7/1/un-report-lists-companies-complicit-in-israels-genocide-who-are-they
#politics #bigtech #degoogle #aljazeera #palestine #gaza #israel #genocide #lockheedmartin #ibm #microsoft #alphabet #google #amazon #palantir #chevron #cat #airbnb #volvo #bp
Some twenty years ago you could just order stuff on the Internet for free. Big companies were giving away cool things: I remember you could get IA-32 programming manuals from Intel at zero cost (and zero shipping costs).
Me being stupid me got this. A whole package of IBM DB2 8.1 for AIX (32-bit) disks including learning materials.
I still wonder what to do with these.
There's zero chance of me stumbling upon an AIX-supported hardware.
“Just as Nazi Germany’s crimes could not have been committed without the technology IBM provided to track, round-up and murder Jews, Romani people and the disabled, Israel’s apartheid and genocide of the Palestinians would not be possible without Microsoft.”
https://thegrayzone.com/2025/05/23/microsoft-hub-israeli-intel/
#microsoft #israel #genocide#ethnicCleansing #apartheid#settlerColonialism#BigTech #capitalism #fascism#IBM#Holocaust
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