Alan, The original 3271 controller was BSC[1] and the 3272 was the channel-attached controller. As Shmuel Metz mentions below - and who can gainsay him on points of this nature? - they emerged together - which is what I would have said if asked out the blue.
This is supported in a round-about way by GA27-2749-5, the "IBM 3270 Information Display System Component Description" (Nov. 1975) which Bob Rutledge pointed out earlier in the thread is available at bitsavers.org. Note that the manual had undergone 5 revisions by November 1975. In the list of devices comprising the "3270 Information Display System" are the following (shame it's not possible to "copy and paste" this scanned document): | IBM 3271 Control Unit, Models 1, 2, 11, and 12 IBM 3272 Control Unit, Models 1 and 2 | IBM 3275 Control Station, Models 1, 2, 11, and 12 IBM 3277 Control Station, Models 1 and 2 IBM 3284 Printer, Models 1, 2, and 3 IBM 3286 Printer, Models 1 and 2 IBM 3288 Line Printer, Model 2 The revision bars are for the 11 and 12 models of the 3271 and 3275 which are the so-called SDLC models. These models are associated with the SNA announcement and thus the 3272 predates SNA - and the so-called SDLC 3271 - QED. In the pre-SNA 1970s, the 3271 was supported in CICS by means of BTAM - I have the scars. One particular scar was being told that the Cyrillic version of the 3271 (based on the Katakana I seem to remember) used X'BF' as the polling character rather than X'7F' after I had installed a CICS demonstration package at the first Soviet customer's installation in Moscow with the mission to show that the devices did work - and they just didn't work. Fortunately (a) I was allowed to leave and (b) a week or so later, someone pointed out the necessary change to my friend Roman and he made the demo package burst into life - as I was happily told. As for the SDLC flavour of the 3271, this came out as part of the hardware announcement to accompany SNA - again, other contributors feel free to fine tune this remembrance. The package covered the 3271, 3767, 3770 range (not the 3777 or the MLU 3776) and the 3790[2][3] - I think. After all what's the point of having a fancy new "architecture" if all you have to show it off is some software with nothing to "talk" to.[4] [1] At least one customer I knew of in the early 1970s - a bank, now very significant and having the most magnificent head office banking hall - ran their BSC 3270s on 1 200 bps lines, probably multipoint. [2] I have a set of education material, an Independent Study Program, "SNA Environment - Logical Data Flow" which was probably intended to cover the initial hardware announcement - but only the general purpose devices so the 3790 isn't there, since, although marketed as "general purpose" was bureaucratically considered "industry" I guess.[5] Thus the ISP "modules" cover the 3270 (PU type 1), 3767 and 3770. The date is April 1977. A "module" was added in March 1979 to cover the 3274 and 3276. [3] I seem to remember that the 3600 and VTAM enjoyed a symbiotic relationship in the pre-SNA days which the banking folk cared about. Although I was supposed to be a networking specialist, I tended to get distracted into matters like writing an operating system in order to run the 1287 and enabling assembler programs written for 360-like hardware to run on real 360s or 370s. My networking was mainly focused on getting CICS actually to work so I'm afraid I let pre-SNA VTAM and TCAM largely alone. Being asked to get the Cyrillic 3270 to work was my excuse to take a sabbatical covering 1975 so that my first contact with SNA was talking about it - with alternating translation - to an audience in the National Hotel in Moscow - and next a ski resort with an unpronounceable name[6] in what is now the Czech republic. I've wandered off my topic. I meant to say there are probably other "industry" peripheral devices which got announced around the time of the SNA announcement even if they did not, like the 3600, exist already - stores and supermarkets come to mind. [4] Strangely enough, since the secondary LU support for the "non-SNA" - pre-SNA channel-attached - 3272-connected 3270 devices resided in VTAM, they were supported without needing a hardware announcement. This also applied to the BSC 3270 connected through the SNA-enabled NCP. [5] Wasn't the 3790 originally considered to be absolutely ideal for the "insurance" industry before clever folk in IBM sensed wider opportunities? Chris Mason ----- Original Message ----- From: "Alan Altmark" <[EMAIL PROTECTED]> Newsgroups: bit.listserv.ibm-main To: <IBM-MAIN@BAMA.UA.EDU> Sent: Friday, 01 September, 2006 8:53 PM Subject: Re: >27x132? > On Friday, 09/01/2006 at 10:50 ZW3, "Shmuel Metz (Seymour J.)" > <[EMAIL PROTECTED]> wrote: > > In <[EMAIL PROTECTED]>, on 09/01/2006 > > at 10:18 AM, Chris Mason <[EMAIL PROTECTED]> said: > > > > >Well, I had difficulty finding how best to describe the "non-SNA > > >channel-attached" mode of 3270 connection. It actually doesn't seem > > >correct always to be calling it "non-SNA" when it predates SNA. > > > > The IBM documentation uses the term local non-SNA. > > If memory serves, BSC and SDLC terminal controllers existed long before > you could assign a CUU to a 3270. And in MVS those were handled by the > SNA implementation of the day (VM had native BSC support). Enter the > "non-SNA" solution for 3270s. And to differentiate it from "remote" > controllers (R models), it is "local" (L models). > > Alan Altmark > z/VM Development > IBM Endicott ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
