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snuci
January 31st, 2017, 02:41 PM
I have recently acquired an IBM 3277 Model 2 terminal and was wondering two questions which I know you guys can answer quickly.

1. Was there ever an IBM model 3270 terminal or is this the series name that developed into the protocol moniker?
2. Did anything come before the 3277 Model 1 (40 columns x 12 rows)?

Any replies would be greatly appreciated.

Chuck(G)
January 31st, 2017, 03:56 PM
Are you talking about text-only terminals or graphics? The IBM 2250 was a very early graphics terminal.

snuci
January 31st, 2017, 04:10 PM
Are you talking about text-only terminals or graphics? The IBM 2250 was a very early graphics terminal.

Sorry, I should have been more specific in question 2. I am talking IBM 3270 series terminals only.

Chuck(G)
January 31st, 2017, 04:21 PM
Ah, I was about to mention the 3740's predecessor, the ugly little 2265 (http://bitsavers.informatik.uni-stuttgart.de/pdf/ibm/2265/GA27-2731-2_2265_2845_Component_Description_Jan70.pdf) 15 lines of 64 or 12 lines of 80 characters.

AFAIK, there were only the 3275 and 3277 for display; the 3275 was essentially meant for remote (i.e. modem) connections and was introduced at the same time as the 3277.

krebizfan
January 31st, 2017, 04:21 PM
The 3270 was the name given to the entire series, not a specific device. I can't find exact dates on when the various pieces were released but the 1971 manual available on Bitsavers lists both the 40x12 and 80x24 systems so it looks like the 3277 and 3275 were simultaneously released in both Model 1 and Model 2 versions.

On a budget, get 3271* and 3277 both in Model 1 badging. Like the high resolution terminal, you need 3271 Model 2 to pair with the 3277 Model 2. 3271 Model 2 can also control 3277 Model 1. Or get the 3275 instead of 3277 and skip the 3271 but pay a lot more if installing many terminals.

* I should double check but the 3271 and 3272 were similar controllers for 32 terminals and printers that used different methods to connect to a mainframe.

g4ugm
February 1st, 2017, 02:27 PM
I don't think there was ever a 3270 terminal. I thought the controllers were 3274 but I can see from Wikipedia others existed.

legalize
February 1st, 2017, 08:00 PM
IBM 2265 (http://terminals-wiki.org/wiki/index.php/IBM_2265) added to the wiki. I could use some help from people who know IBM stuff to flesh out this area of the wiki. IBM stuff is so alien to me.

Chuck(G)
February 1st, 2017, 08:56 PM
I'll wager that Univac, Burroughs, NCR, Honeywell and CDC stuff is foreign also.

legalize
February 1st, 2017, 09:03 PM
Burroughs and CDC I have some personal experience; UDel had a B6700 and a CDC Cyber running PLATO. The Burroughs machine talked ASCII to half duplex terminals. The half duplex thing was a little weird, but other than that the experience was pretty standard time sharing for the day. PLATO of course is a different beast entirely.

legalize
February 1st, 2017, 09:08 PM
The Westinghouse W1642 (http://terminals-wiki.org/wiki/index.php/Westinghouse_W1642) is more like an IBM terminal than anything else that I have. I have a bunch of these airline/travel reservation terminals (some with credit card readers on the keyboard) that I need to figure out some day. I've been trying to read up on SNA/HDLC/3270 networking and protocols, but it's a tough slog when you don't know where to start given the voluminous piles of documentation in IBM land.

Chuck(G)
February 1st, 2017, 09:16 PM
How about the CDC 200 series text terminals? There were all over CDC SVLOPS in the early 70s, which is also where the Digigraphics stuff was supported. Hapless poor sods. Neat technology, but it was apparent that management didn't give a toss about the IGS 200 people.

legalize
February 1st, 2017, 09:25 PM
I can create an account on the wiki for you :)

g4ugm
February 2nd, 2017, 01:08 AM
Lots of folks made 3270 clones. I have some badged as Nokia and on Memorex or is it Memorex-Telex, not sure...

snuci
February 2nd, 2017, 03:44 AM
Thanks for the replies and continued conversation. I put up a quick post with some pictures here: http://vintagecomputer.ca/ibm-3277-terminal/ What I should have done is take some pictures of the internals and cards but that thing is a beast to handle (90 lbs) and after I struggled to put it in the box, it occurred to me that I forgot to take those pictures.

Legalize, if you want to use the pics for the terminal wiki (which I use all the time), you have my blessing.

Thanks.

Chuck(G)
February 2nd, 2017, 05:47 AM
Back in the 80s, I scavenged some stuff from similar Fujitsu terminals--turned them into mono monitors. I still have a few PCBs from them--all 74LS logic with a few custom ICs. Fed with an odd biaxial connector--a two-pin affair; polarized with a D-shaped recess. Memory was a set of 4Kx1 DRAMs.

g4ugm
February 2nd, 2017, 07:21 AM
Back in the 80s, I scavenged some stuff from similar Fujitsu terminals--turned them into mono monitors. I still have a few PCBs from them--all 74LS logic with a few custom ICs. Fed with an odd biaxial connector--a two-pin affair; polarized with a D-shaped recess. Memory was a set of 4Kx1 DRAMs.

twin-AX? IBM mid range?

Chuck(G)
February 2nd, 2017, 08:40 AM
Probably, that was my guess--but the connector is a real puzzle. As was mentioned--3270-type terminals were very common.

legalize
February 2nd, 2017, 09:34 AM
Legalize, if you want to use the pics for the terminal wiki (which I use all the time), you have my blessing.

Pics added and I'm glad you find the wiki useful.

MossyRock
February 9th, 2017, 07:59 PM
Here is a list of all 3270 series terminals: https://en.wikipedia.org/wiki/IBM_3270#Models

The 3279 color terminals were quite popular. We had quite a few of them at Westinghouse in the 1980s.

frankt
April 8th, 2017, 01:24 PM
IIRC, the original 3270 communication protocol was Bi-Sync (bit synchronous, character synchronous). HDLC and SDLC (SNA) evolved later.

g4ugm
April 8th, 2017, 02:38 PM
There are two parts to 3270 communications. The terminals all connect to a controller via coax cables, and there are two types of terminal type-a and type-b. This interface runs at 1Mbit at up to 1000Yds. Amazing for its launch date. The controller then speak to the host via a second protocol.

Originally they were either directly attached to a mainframe bus & tag channel which ran at 1MByte/sec (8MBits), or could be remotely attached through a 2708 comms controller, and as you say the protocol used on the link to these was Bi-Sync.

Later when IBM produced SNA then they could be connected via SDLC and SNA (NOT HDLC which is for X.25). Not sure of the time frame but additional connection types were added later, so X.25 over HDLC, SNA over Token Ring, and SNA over Ethernet and SNA over TCP/IP.

The later controllers also support connecting to non-IBM hosts by Telnet or by remote IBM hosts using TN3270 so again no SNA required...