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XT/370 or 3270 PC

lyonadmiral

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I recently acquired the 1984 Special Issue for IBM Computers Byte Magazine, and in this issue it talks about all of the available IBM personal computers at that time including the XT/370 and the 3270 PC. I know these are geared more for high end because of their attachment capabilities to mainframes and one of them can even run mainframe instructions locally. Does anyone here on the forum have either of these?

Thanks,
Daniel
 
Hi Daniel,
I used to have an XT/370 many years ago. It was discarded by a software development company and I got it along with several other neat machines (IBM RT, DecStation, Data General Aviion, etc...)
After holding on to it for almost 5 years it ended up in the trash in the late 90's (big mistake on my part). The computer ran just fine and was hardware complete and it ran DOS and the IBM VM mainframe OS.
It was a neat curio but nothing else. Would make for a nice collectors item today.
 
Early in my career I was a technical writer for MVS + JES2 and JES3 (HASP and ASP :). In order to learn the various facilities (writing exits, doing diagnosis, messages, init & tuning, conversion notebook etc) I installed a S/370 emulator in my PC/XT so I could run the OS and subsystems. I am not sure if the XT/370 wasn't just an XT with the same emulator adapter, or had more to it than that. I do know you can go on eBay and someone there offers a CD with all of the various OS's (MVS, JES2/3, TSO, RACF, VM etc) pre-configured to run on a system with the s/370 emulator (if you have one) at a pretty decent price for just the CD.

Regards,
Mike
 
IBM offered the cards to upgrade a regular XT also. These same cards also made it to an AT/370 (I've never seen one of these though).
The excellent Hercules emulator will run almost almost all the S/370, S/390 and Z-series OSes. If you don't want to buy a pre-made CD like Mike mentioned you can download yourself:
Emulator here:
http://www.hercules-390.eu/

Legacy mainframe OSes here (like MVS, VM, etc...)
http://www.cbttape.org/

BTW, if you can't get this stuff running in the emulator first don't even bother with a "real mainframe" like the XT/370. It will be much more of a pain in the butt with the real hardware....
 
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Hi Daniel,
I used to have an XT/370 many years ago. It was discarded by a software development company and I got it along with several other neat machines (IBM RT, DecStation, Data General Aviion, etc...)
After holding on to it for almost 5 years it ended up in the trash in the late 90's (big mistake on my part). The computer ran just fine and was hardware complete and it ran DOS and the IBM VM mainframe OS.
It was a neat curio but nothing else. Would make for a nice collectors item today.

I think it would be neat to have one, maybe even with the expansion unit, just an idea. Will be interesting to see if someone in the community has it.
 
Dag, this whole thread has brought back Program Logic Manual PTSD! I need a diagnostic code - where's the Exit?

:D
 
I think bear has one. I've seen pictures of it at least sitting on a table running. As for the 3270 PC someone here sold most of the boardset a month ago and personally I have the keyboard and Y-cable but nobody that I am aware of has the special keyboard card that brought all the components together, or the monitor.
 
It's true that I have an XT/370, and some of the remains of an AT/370 (no /370 CPU alas). And a 5271. With the keyboard and monitor. And a 5273.

I am not sure why anybody would be disappointed that Hercules won't run the "special" CMS for this system, since it is in every respect a less functional equivalent of the exact same CMS you can already run on Hercules (it's cut down from... VM/SP R3 I believe). There are lots of things it can't do. You're not missing out on anything. There's no reason to want it.

Yes, you can attach a 5161 expansion unit to any of them. I use one with my XT/370. It's the only way IBM supported attaching two hard drives to an XT.
 
I am not sure why anybody would be disappointed that Hercules won't run the "special" CMS for this system, since it is in every respect a less functional equivalent of the exact same CMS you can already run on Hercules (it's cut down from... VM/SP R3 I believe). There are lots of things it can't do. You're not missing out on anything. There's no reason to want it.

I don't think the CMS is cut down in any way, and if you have a copy from a dead XT/370 and don't have a copy of VM/SP3 you might want to be able to run it. Its certainly much better than the CMS from VM/370R6 which is the latest one can legally get hold of...
 
That's fine, I suppose you're entitled to think whatever you like. Perhaps you'd also like to make yourself acquainted with Appendix C of the VM/PC user's manual, which enumerates the differences between VM/PC 1.0 and VM/SP (R2 as it turns out; VM/PC 1.10 might have been derived from R3). Some of the differences are going to concern limitations of the hardware and differences in CP. But there are also differences in CMS, including removed commands (no virtual tape or unit record devices) and a cut-down CMS MACLIB.

https://archive.org/stream/bitsaver...530_VM_PC_Users_Guide_V1.0#page/n377/mode/2up

I'm not sure what the legality of VM/370 R6 has to do with anything; even if Hercules could run PC/CMS it would still be illegal by the terms of the license agreement.
 
That's fine, I suppose you're entitled to think whatever you like. Perhaps you'd also like to make yourself acquainted with Appendix C of the VM/PC user's manual, which enumerates the differences between VM/PC 1.0 and VM/SP (R2 as it turns out; VM/PC 1.10 might have been derived from R3). Some of the differences are going to concern limitations of the hardware and differences in CP. But there are also differences in CMS, including removed commands (no virtual tape or unit record devices) and a cut-down CMS MACLIB.

https://archive.org/stream/bitsaver...530_VM_PC_Users_Guide_V1.0#page/n377/mode/2up

I'm not sure what the legality of VM/370 R6 has to do with anything; even if Hercules could run PC/CMS it would still be illegal by the terms of the license agreement.

The R2 manual is on Bitsavers and it says VM/PC1.1 is based on SP3. It is more cut down that reading the documents on the VMSHARE archives had intimated....
... a note here about who had them..

http://vm.marist.edu/~vmshare/browse?fn=XT370USE&ft=MEMO&args=KEYS#hit

and lastly I haven't seen a licence for the VMPC software. I believe that some of the later stuff for the P370 and P390 cards simply said the software could only be run on the PC containing the card, which some interpreted as meaning it did not even have to be installed, just inside the case...
 
I bought a 3270(/G) for the 5161 extender card which was in it. Two 360k disk drives were in it, EGA card without daughter card, 640k, and more add-ons, except the keyboard.
This is one of few devices I've not powered-on, yet. I have read that you can remove the special card from the ISA slot the you can use a regular xt keyboard in the KB 5 pin din.
IDK what the bios is comparable to.. maybe a late model XT.
 
I worked for short time on the 3270PC in Kingston NY. and was later Country Specialist. Sadly all my manuals etc. went years ago. Although an extremely good 3270 terminal, the 3270PC was not much of a PC, mostly because the PC graphics was hopeless.

The reason for the design was that although IBM CPD (Communications Products Division) considered the IBM PC Monochrome Monitor acceptable for the role (there was actually a mono model based on that monitor) the IBM PC Colour/Graphics Adapter and IBM PC Colour Monitor was not thought to be high enough quality for 3270 use. Additionally, CPD only released the 3270 Adapter card (Diago) as part of the 3270PC for many years; allowing the IRMA card a free run. (The code names are all based on Columbus.)

The later 3270PC-G (Aragon) and 3270PC-GX (Genoa) were Hursley products but sadly, other than few pictures the Hursley Museum doesn't have any examples of the products. (If anyone on this side of the pond has any bits of Aragon and Genoa, the Hursley Museum is looking for kit.)

I remember XT/370 and weirdly the 3270 card for communicating with a mainframe was a B Type (ANR).
 
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