Purpose of a "mystery key" on an IBM PC 3270 keyboard

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A colleague has just come into possession of a large number of IBM PC 3270 keyboards (don't ask!). These keyboards have a number of very interesting looking keys, but the one that most intrigued us is the one at the bottom right of the block illustrated here:

Keyboard picture

In the absence of knowing its purpose, we've nicknamed it the "person in a wheelchair being chased down a hill by a boulder" key. We are relatively confident, however, that this isn't its actual name.

Any PC/mainframe history buffs able to help us out?

Cowan

Posted 2011-05-31T04:43:39.917

Reputation: 1 541

1

On IBM's current keyboards, they have replaced that with this more descriptive key: https://i.stack.imgur.com/mUtpD.jpg

– fixer1234 – 2016-11-01T18:32:04.370

138It's clearly the "any" key. Press it to continue. – Trezoid – 2011-05-31T07:27:23.417

3What happens ... when you press it? That might help you sort things out a little. – Justin Jenkins – 2011-05-31T09:30:58.570

36Quite possibly the best key nickname ever – Eran Galperin – 2011-05-31T09:35:15.987

15"person in wheelchair being chased down a hill by a boulder" -- Maybe call it "Indiana (Jones) Key" then? – Nicolai Reuschling – 2011-05-31T10:22:04.567

2I wouldn't want to meet that 'a' down a dark alley... – adolf garlic – 2011-05-31T10:22:48.347

60The key next to it is called "wheelchair guy finally found a shelter key" and the leftmost one is called "solve zeno paradox key". But I've never heard of the one you're asking. – Sedat Kapanoglu – 2011-05-31T10:29:15.110

1These keys with funny symbols on old keyboards tend to be shorthand notation. – sylvanaar – 2011-05-31T13:45:56.877

1Don't press it. Maybe the boulder will fall on you! – Carlos Muñoz – 2011-05-31T15:28:24.553

14Disappointed that this isn't about a key with 'Mystery' written on it – Dancrumb – 2011-05-31T17:01:35.367

4What I love about this is it shows the history and evolution of though about computers from being extensions/mimickers of manual processes (writing, typewriters,etc.) into something complete different (what we have today). Where will we be in another 10 years?? :-) – richard – 2011-05-31T19:12:26.897

You mean the "deleatur" symbol? – loevborg – 2011-05-31T20:26:21.197

3@Justin Jenkins - nice theory, but it has a horrid DIN connector (not AT-connector compatible, apparently) and a non-standard set of scancodes. So plugging it in is a challenge, let alone pressing it.

Thanks for the awesome answers everyone! – Cowan – 2011-05-31T22:56:22.000

1

@Cowan Here's a related topic you might know the answer to.

– Daniel Beck – 2011-06-01T15:25:47.960

Answers

169

I do know the symbol on the bottom right key as being the symbol typically used when proofreading written documents. It is a delete. When you write that over a letter or word in a paper, it indicates that it is unneeded and should be removed. Seeing as how this is an older keyboard, the users of the equipment at the time likely would be very familiar with proofreading symbols and understand what it represents.

My guess (without having used the machine in question) is that it likely is the delete key.

This page goes through a history of some IBM keyboard layouts, and a few pages down you see this image:

IBM 3270 keyboard layout

You can see the key layout in your screenshot above the arrow keys. The key layout is:

Dup/PA1    FM/PA2    PA3

Back Tab   Insert    Delete

The delete mark on the key makes sense, especially combined with the proof-reading mark also used for "insert".

Ben Richards

Posted 2011-05-31T04:43:39.917

Reputation: 11 662

15It makes sense. I remember an old guy I knew doing proofreading of a document. To show that a character should be deleted, draw a line starting at the character, going to the upper right, and put a little loop on the end. It looks sort of like that picture! – GEdgar – 2011-05-31T13:58:35.587

2Also makes sense wrt the key to its left: the "a with a hat" is like the proofreading symbol for "insert this text here" – Adam Bellaire – 2011-05-31T14:24:25.560

9http://webster.commnet.edu/writing/symbols.htm – richard – 2011-05-31T16:15:37.760

Amazing, I thought it meant: Delete a character (a) or symbol (°). ° is on the first symbol from the top-left on German keyboards, on the key directly below Esc. – ste12 – 2011-05-31T16:31:47.037

125

This is an IBM 6110344 keyboard and the keys on the 6110344 are laid out like this:

enter image description here enter image description here

So the key you're looking for corresponds to scan code "6D". When we look at the related scan codes on the link given above, that key turns out to be Del, namely Delete.

enter image description here

Mehper C. Palavuzlar

Posted 2011-05-31T04:43:39.917

Reputation: 51 093

17This is what the scan code means now, but at the time that key was not "page down". – Stephen Jennings – 2011-05-31T07:55:16.333

3@Stephen Jennings: Sorry, I looked at the wrong table. I've fixed my answer. – Mehper C. Palavuzlar – 2011-05-31T12:30:03.367

1Palavuzlar: Ah, so you're right. I missed that as well. – Stephen Jennings – 2011-05-31T22:25:07.373

63

The symbol you nick named as 'person in wheelchair being chased down a hill by a boulder' is for indicating that the alphabet is wrong.

enter image description here

Closely looking at the key we can separate the a and the other symbol .

The other symbol is indicating wrong sign.

enter image description here

something like we use for right enter image description here & wrong enter image description here. This symbol is shown in slightly different angle indicating strike off the alphabet (or delete the alphabet).

enter image description here

Vinod

Posted 2011-05-31T04:43:39.917

Reputation: 731

3@Vinod: Do you have any reference to back up your claim? Because I see with a /... – Tamara Wijsman – 2011-06-01T00:27:40.070

@Vinod The major clue is a couple of symbols that are left for the prospective victims. It's a great show BTW, available online at Netflix. (And no, I don't work for Netflix or BBC) – JeffSahol – 2011-06-01T00:43:15.597

@JeffSahol: I will watch this weekend..:) – Vinod – 2011-06-01T07:50:28.540

@Tom Wijsman: I think the last image put up in this answer matches well with the key shown in this key layout (observe the first image in Scancodes section).

– Vinod – 2011-06-01T07:54:40.240

@Vinod: Still, it's odd that the picture of the OP has a straight /. – Tamara Wijsman – 2011-06-01T09:18:29.607

5Thanks for the pictures! Some day you will have to present old pictures of floppy disks to illustrate how the "save" icon came to its shape :) – Jakob – 2011-06-01T11:27:42.290

My English teacher in High School used to indicate "omit" with that symbol. This is almost the same as "wrong," but I like "omit" better. =) – Randolf Richardson – 2011-09-23T23:15:58.610

21

(a/°) is the DEL key. At its left is the INSERT key (â).

plodoc

Posted 2011-05-31T04:43:39.917

Reputation: 311

12

It does look like a proofreading notation. A letter with a bar crossing it out and a circle. Refer to delete in this page: enter image description herehttps://people.sunyit.edu/~russ/Com310/ProofreadSymbols.pdf

Mallow

Posted 2011-05-31T04:43:39.917

Reputation: 309

4

That's funny, because, in Unicode, there is a symbol for insert (⎀) but I never found it used. Here, â seems really near the "insert" function (but, ô tempora ô mores, too strange for European users), so the strange symbol seems to mean "delete".

Da Scritch

Posted 2011-05-31T04:43:39.917

Reputation: 41

4O tempora, O mores didn't have the hat signs, I believe. – Clément – 2011-06-01T18:02:46.207

Accents were probably too strange for poor Roman stonecutters. – XTL – 2012-03-07T12:19:39.217

2

Check out the first item in this list: http://wadsworth.com/english_d/templates/student_resources/1413001890_burnett/UsageHandbook/edit_marks.htm

It's supposed to be the old fashioned delete symbol. You may remember this symbol from elementary school, but I guess most people have probably never seen it. Myself, I haven't hand-written a school paper since at least 5th grade (1997ish), so it's been quite a while.

mcallister

Posted 2011-05-31T04:43:39.917

Reputation: 21

0

This is the keyboard for an IBM 3290 Plasma display (Perhaps a specific model - I don't remember.). That's the zoom key. The display could be configured as 1 LU or 4 tiled LU's on the screen. The zoom key zoomed into the active tiled LU, filling the large screen. Our operators loved the big single screen!

I configured a number of 3274's to work as 4 LU's. Some of the business guys used the display to view a printed page at 160 columns, 50(?) rows.

IIRC, the top symbol was also the letter "a" - the same as the bottom symbol but smaller. Maybe it was scratched off. It was intended to indicate zooming!

I never saw an application which used the PA3 key either!

Joe S

Posted 2011-05-31T04:43:39.917

Reputation: 1