IBM Mainframe terminal stuff

Paul Berger phb.hfx at
Fri Dec 18 20:45:29 CST 2015

Its possible, but you need a modem eliminator mostly to provide the 
clocks for the sync data line, other than that is is similar to a null 

I remember the control units being pretty much trouble free however the 
3277 terminals,3284 and 3286 printers where a different story.  What I 
remember of the 3277 is they seemed to never have solid problems always 
seemed to be intermittent.  We would swap groups of cards between 3277s 
in an attempt to isolate and leave notes in the terminals saying what 
cards where swapped and why, and you would find notes from years before 
buried in the dust from people who had done the same thing before.  The 
3284 and 86 printers could be a bit of a nightmare, like the rest of the 
system they where all hardware and the printing was timed by toothed 
where and emitters that detected the teeth playing with them usually led 
to trouble.  I remember times when the carrier would take off at full 
speed and slam into the right frame reverse and slam into the left frame 
while you scrambled to get to the power switch.  The 3287 printer with 
the adapter to attach to 3271/2 was a God send.


On 2015-12-18 10:32 PM, Mike Ross wrote:
> I have a 3271 Model 2 - the remote bisync one. It's in embarrassing
> condition; I'll take pics once it's cleaned up! Only IBM product I
> have with significant wood in it; the top panel of the unit is made of
> formica-covered chipboard!
> No docs.
> I wonder if it might be possible to finagle it into working with my
> 3277 by a direct hookup to a serial port on a P/390, or a machine
> running Hercules?
> Mike
> On Sat, Dec 19, 2015 at 2:39 PM, William Donzelli <wdonzelli at> wrote:
>> Do you have a 3272? I found one during the cleanup of the Black Hole.
>> I think I can get ALDs and docs for it.
>> --
>> Will
>> On Fri, Dec 18, 2015 at 8:30 PM, Mike Ross <tmfdmike at> wrote:
>>> grrrr 3271 and 3272 controllers I should have said! They're much
>>> dumber than 3174 - no program load device whatever; all done in
>>> hardware. Just an on/off switch and a couple of status lights.
>>> Mike
>>> On Sat, Dec 19, 2015 at 2:27 PM, Mike Ross <tmfdmike at> wrote:
>>>> Oh sounds like fun!
>>>> I'm working with 3277 which uses a different protocol; connects to
>>>> older mainframes (360/370) via 3171/3172 controllers - channel
>>>> attached or remote. Also connects to System/3 direct to the CPU
>>>> hardware as a console. I have a 3172 controller; physically rough and
>>>> needs restoration but *should* work if I can fake the remote
>>>> connection and modem - bisync etc. But just now I'm working with
>>>> Henk's 3277->RS232 converter - trying to get it hooked up to an
>>>> emulated System/3 -
>>>> I've played this game a lot - including telnetting into Linux from
>>>> 3270 screens - see
>>>> Please let me know when you manage to ship those 3174 diskettes to
>>>> Henk; I know he's keen to get them ASAP.
>>>> Mike
>>>> On Sat, Dec 19, 2015 at 12:00 PM, Guy Sotomayor <ggs at> wrote:
>>>>> I’ve been tinkering around with my IBM Mainframe terminals and I’m pretty close to having everything the way that I want it.
>>>>> I currently have an IBM 3174-61R Establishment controller connecting to my “mainframes” via TCP/IP.  This allows me to not only connect to my Multiprise 3000 S/390 but also some PCs running Hercules to allow me to run older versions of the mainframe OS’s.  I currently have 3 IBM 3179 terminals hooked up.
>>>>> I’ve upgraded the 3174 to be able to boot from a hard disk (it was a supported option).  I actually purchased the upgrade from a reputable vendor but after many attempts we could not actually get it to do anything useful.  I learned about DavidG’s MFM emulator and that’s now installed in the 3174 which happily boots from it.  I still have to figure out a permanent mount for it since the standard 3174 HDD mounts don’t work for the MFM emulator board.
>>>>> One of the last things that I wanted to figure out was how to support multiple sessions.  I had configured the 3174 to support multiple sessions on each terminal but following the documentation, I could never figure out how to actually switch between the sessions.  Well today I managed to do that.  Success!  I finally figured out the key sequence for switching sessions.  It doesn’t match the IBM documentation.  It’s not clear to me if that’s because I haven’t configured something properly on the 3174 or if there’s some other reason behind it.
>>>>> Since I also have the AEA feature that allows me to connect ASCII terminals to the 3174, my next project will be to hook up a couple of the terminals that’re deemed “compatible” (VT100, ADM5 are on the list) and see how that works.  But that also involves navigating the 3174 configuration process which is opaque to say the least (there are configuration screens but you need a manual because the fields only have numbers (e.g. 721) to identify them and no other indication as to how they need to be filled in).
>>>>> Oh, the other bizarre thing about the 3174 that’s been configured with TCP/IP is that I can also connect to “unix” servers with the 3174’s (and the ASCII terminals too).  It’ll be interesting to see how that works on a CUT mode terminal.  ;-)
>>>>> TTFN - Guy
>>>> --
>>>> 'No greater love hath a man than he lay down his life for his brother.
>>>> Not for millions, not for glory, not for fame.
>>>> For one person, in the dark, where no one will ever know or see.'
>>> --
>>> 'No greater love hath a man than he lay down his life for his brother.
>>> Not for millions, not for glory, not for fame.
>>> For one person, in the dark, where no one will ever know or see.'

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