the 1401 (1410/1440/7010/etc) emulators were microcode. an extra cost for the microcode and probably another extra cost for the read only storage for the extra microcode.
Initially, on the 360s, you could push buttons on the console, and have one or more 14xx series machines if you had enough memory. perhaps with 370s too. then you could IPL a card deck with a minimal 360 in-memory operating system, and run one or more 14xx series machines with console commands (I think, I never did this) ' THen you could run a program in one of the dos partitions (BG,F1.F2) that would dynamically start a 1401 job by reading in the 14xx program from cards, while running a native 360 program in the other partition, all as batch jobs scheduled by reading them into the card reader There was also 1620 emulation and maybe others., By the time my employer got to 370 I think they had gotten rid of the 14xx emulation, but they were availble. On Sat, Feb 7, 2026 at 3:36 AM David Wade via cctalk <[email protected]> wrote: > > > On 07/02/2026 03:51, Steve Lewis wrote: > > Dave, > > > > Page 439 of that document you linked has a nice chart of "integrated > > emulators that run execute under VM/370" - now I do recall one of the > > "famous" things about the prior S/360 was it could emulate 1401 and > > other IBM systems. Then later on, more systems to emulate would be > > the 709-series. Ok, so VM/370 is more like what we might today > > call a Hypervisor? So the "it looks like whatever you want" comment > > makes sense. > > > You don't need VM to emulate a 1401, I believe the 1401 emulator ran > under MVS as well, or I think on some S/360 machines you could load 1401 > microcode. > So yes VM itself is what today we would call a hypervisor. It creates > virtual machines and each virtual machine is pretty much totally isolated. > But CMS was provided as source code, and in the early days it was very > limited so sites made many modifications. > > > I suppose what I'm after is more a visual on the usage of CMS, DOS/VS > > or OS/VS1 ( OS's that one would only use on an S/370 ? ) > > > > There was also MTS and MUSIC plus a few other TSO and CICS replacements. > > > I put a couple reference images here on what I have about CTSS and > > TOPS-10 (CTSS is from a modern-day emulators, TOPS-10 is from one of > > their manuals so its from in 1970). I see how you mean VM/370 isn't > > quite the same nature (not "just an OS" but an enterprise thing like > > for airlines, banks, financial brokers -- and the virtualization > > helped in testing/deploying new systems -- that maybe had newer OS's > > -- without disrupting operational systems?) > > > > https://github.com/voidstar78/OS_NOTES > > > OK I can do something similar for VM and CMS but got a busy day here:- > > https://www.scienceandindustrymuseum.org.uk/whats-on/meet-baby > > (yes thats me, the rest of the team are camera shy) > > > > > - Steve > > > > > > > Dave > > > > On Fri, Feb 6, 2026 at 10:00 AM David Wade <[email protected]> wrote: > > > > > > > > On 06/02/2026 14:55, Steve Lewis wrote: > > > Thanks Dave, the 3270 terminal screen makes sense. Or to make > > use of > > > the system and resources, you'd remote to it using a 3270. > > > So it may have been at a time no one thought to snap a > > photograph of > > > any of those 3270s in use (not just a "room full of 3270's" kind of > > > photo - but of the actual screen, showing whatever it was they were > > > doing; managing tape/disk resources, files, users, or running > > APL or > > > something. That's more what I was looking for, when you "used > > VM/370 > > > {or remoted into it}, this is what it looked like." > > Generally thats not what you did with VM/370. You edited, > > compiled, and > > ran programs.... > > > > > > > > There had to be some kind of installer? Or maybe I'm viewing it > > wrong > > > - they (a business) didn't just buy a S/370 then decide what OS to > > > install. But rather it was a packaged prepared by IBM, so maybe it > > > was pre-installed with VM/370 and configured to whatever the > > > arrangement/contract was? > > > > For VM you usually got a "starter system" on a tape. There was a > > different tape for each disk type. The first file on the tape is the > > standalone disk dump and restore program, DDR. So you IPL (boot) from > > this tape, and use DDR to restore the starter system to DASD (disk). > > You usually needed three packs. The first time you IPL the restored > > starter system it asks you some basic config questions, and you then > > have a working system that you can use to restore the rest of the > > VM/370, load and apply service (fixes) , and configure to your exact > > hardware set-up. > > > > I expect at 522 pages this manual which covers install and > > congigureis a > > tad bigger than the one for other systems... > > > > > https://bitsavers.org/pdf/ibm/370/VM/370/Release_6/GC20-1801-10_VM370_Sysgen_Rel_6_Jan80.pdf > > > > > > > Or a way to say "when someone used a S/370 {or CMS}, this is > > what the > > > console content looked like" (printed, or by that time yea probably > > > more likely a CRT). > > > > > > > It looked like whatever you wanted. The samples in the previous > > e-mail > > are typical... > > > > > > > “The Origin of the VM/370 Time-Sharing System” – R.J. Creasy > > gives a > > > little bit of a description on those components CP, CMS, and RSCS. > > > But no photo/image yet of a terminal with content to identify > > "yeah, > > > see they are using a S/370 there" (maybe its listing disk packs, > > > tapes, memory resources, etc?) I got something like this for the > > > earlier CTSS and TOPS-10. > > > > > pass me what you have for that so I can see what a VM Equivalent > > might > > be. The definitive thing on a users 3270 is the status bottom right > > which on a pukka system which usually reads "VM READ VM/370" but can > > also start "RUNNING", "HOLDING" "CP READ". > > > > > -Steve > > > > > > > > Dave > > > -- --Carey
