Talk:Computer terminal

Green Screen gone ambiguous

The link to Green Screen no longer reaches directly thru to Green_Screen_Display. I'd work harder to fix this but I've forgotten my Wikipedia username. —Preceding unsigned comment added by 67.170.241.65 (talk) 16:05, 15 November 2008 (UTC)

This statement from the article makes no sense

This statement from the article makes no sense: "This class of terminals were later renamed dumb terminals, differentiating them from PCs running emulation software." Terminals have always been differentiated from PCs running emulation software, by actually being terminals. I recognize that some people mistakenly use the term "dumb terminal" to refer to any computer terminal, but isn't that out of ignorance? --Serge 06:41, 12 December 2005 (UTC)

Is the merge actually serious? Command prompt being merged with computer terminal? I almost died laughing. If this goes ahead, we may as well merge the articles on cathode ray tubes and the BBC. Afterall, CRT's display the BBC channels, don't they. Strongly oppose. 82.10.97.111 21:48, 3 September 2006 (UTC)

What is the etymology of this term?

The statement no longer appears in that form; the current version looks reasonable Tedickey (talk) 11:09, 13 November 2008 (UTC)

"little usability of many text-mode applications"

I added citation-needed to the part of the article which states that (interpretation by me):

1. ncurses, terminfo, terminal emulators etc are buggy
2. and so buggy that many applications have "little usability" (i.e. major problems)
3. and all development effort goes into GUIs, so it will probably never be fixed

I use these kinds of applications heavily at work and at home, and I don't recognize this description of reality at all (my only major annoyance is colors, which tend to come in unreadable combinations by default). Furthermore, I have never heard complaints like these raised before, neither by users nor programmers. JöG 15:31, 29 July 2007 (UTC)

I generally see comments such as "buggy" from (a) people who don't know how to select a proper terminal description, or (b) people relating second-hand opinions Tedickey 19:30, 21 September 2007 (UTC)

AlphaWindows

I've added a section on AlphaWindows. I think this is notable since it was a pre-MS-Windows attempt to have multiple sessions on a single screen, however I'm afraid that I can't cite sources simply because so little was published about it (roughly translated: trust me, I'm an engineer :-) I might have one extremely skimpy article on it somewhere but if anybody else has anything (e.g. on what sort of escape sequences it used and how the host operating system saw it) I think it would be of general interest. MarkMLl 18:31, 21 September 2007 (UTC)

1992 isn't pre-MS-Windows. AlphaWindows were a variant such as X Terminal, addressing a lower-end market Tedickey 19:17, 21 September 2007 (UTC)

It was approximately contemporaneous with Windows 3.0, my understanding- but I'm happy to be corrected if you were in some way involved- is that Wyse et. al. intended it to support multiple text- not graphical- sessions, which is why I don't think categorising it as a graphical terminal is appropriate.

When I wrote "pre-MS-Windows" I was specifically thinking of running multiple live terminal sessions under Windows- something that was still rather a novelty in those days. MarkMLl 20:19, 21 September 2007 (UTC)

Celio Technology Corporation

The paragraph appears unbalanced, since it extends a fairly generic description with special mention of a tangentially-related commercial product. If there are "some examples", this probably should be developed first into a general paragraph of their characteristics (contrasting against the existing paragraphs). Tedickey (talk) 00:46, 15 January 2009 (UTC)

I added it because I created the article this afternoon (disclaimer: I have no connection or affliction to the company). As far as I'm aware it's the only product of it's type that's available in the smartphone marketplace - there was suppose to be the palm Folio but that got pulled a week before release. If you are unhappy with it feel free to remove it or rewrite it as you feel fit, however since the paragraph says that dumb terminals have declined in use, I just thought it would be useful to add an example where they are being used in a new way. --Cameron Scott (talk) 01:04, 15 January 2009 (UTC)

Oh I would have linked directly to the terminal itself - the Redfly but em.. I couldn't be arsed to write the article. --Cameron Scott (talk) 01:05, 15 January 2009 (UTC)

What about "thin terminals" (which seem to be merged here with thin client)? Some of those aren't really graphical, since they're advertised as replacements for legacy character terminals Tedickey (talk) 01:09, 15 January 2009 (UTC)

That could be about right - I'm off to bed as it's rather later - if you haven't moved or something when I get up, I'll take another crack at it. --Cameron Scott (talk) 01:12, 15 January 2009 (UTC)

thanks - I think that going in that direction might help Tedickey (talk) 01:23, 15 January 2009 (UTC)

“Text terminals” section

IMHO this section should be splitted to a separate article, merged together with stubs character-oriented terminal and block-oriented terminal. Only a brief general description should remain here. Incnis Mrsi (talk) 16:15, 3 January 2010 (UTC)

Most of this topic is general, covering both. character-oriented terminal and block-oriented terminal happen to be interesting subtopics, but by no means manage to cover the entire topic. Tedickey (talk) 22:53, 3 January 2010 (UTC)

Entire what? “Computer terminal” is a broad topic, too broad to be covered by one article. “Block-oriented terminal” is an narrow subtopic about obsolete hardware, would it be ever expanded to a full article like IBM 3270? May be, but may be not, I don't know. So named “character-oriented terminal” is virtually the most common design of a text terminal (the thing, about what we think as about a text terminal). I can't see any reason to discuss it separately from text terminals in general. “Character-oriented terminal” has no links from articles, except from its counterpart “block-oriented terminal” and through controversial redirect page “Character-cell and block-oriented terminals”. I propose to merge “Text terminals” section with “character-oriented terminal” stub, move the resulting article to Text terminal and fix a redirect “Character-cell and block-oriented terminals”. Incnis Mrsi (talk) 12:15, 5 January 2010 (UTC)

Short - you're proposing to move most of the text-terminal content from this topic to where the existing redirect Text terminal is now? Tedickey (talk) 10:19, 6 January 2010 (UTC)

I think that a separate article “Text terminal” should exist, with a content overlapping with this article. Incnis Mrsi (talk) 20:08, 9 January 2010 (UTC)

I was also thinking that Text terminal should be a separate article, perhaps covering a more abstract topic including terminal emulator and virtual console software. This Computer terminal article tends to focus more on hardware. Perhaps some parts of Terminal emulator could also be integrated into a Text terminal article. I discovered that in 2007 there were actually separate articles; see Old revision of Text terminal and Old revision of Computer terminal just before they were merged. Vadmium (talk, contribs) 03:31, 14 August 2014 (UTC).

xterm can emulate a Tektronix 4014, so presumably it wouldn't belong in "text terminal", as it's not text-only, and it's not hardware, so it might not belong in "computer terminal" either. Where would it go? :-)

(I.e., what distinguishes a "text terminal" from other types of terminal?) Guy Harris (talk) 05:31, 14 August 2014 (UTC)

dumb vs smart

The text as it is right now does not match my understanding. It is true that a real dumb terminal has limited escape sequence processing (whether the cursor is addressable is one distinguishing feature often used) but terminals like VT100 and so on are not "smart". That is reserved for the record-at-a-time terminals - those that receive a form to be edited and send the results back to the computer once the whole form has been completed. General purpose terminals don't do this and need the smarts of the host computer for the entire editing procedure - move from one field to the next, show what has just been typed, and so on. —Preceding unsigned comment added by Minority Carrier (talk • contribs) 16:14, 31 August 2010 (UTC)

The distinction varies according to the source. For something like this, more than one reliable source (illustrating the variation) would be useful. TEDickey (talk) 20:23, 31 August 2010 (UTC)

Article needs work

There isn't enough discussion of different technologies, e.g. "typewriter-like" ribbon on paper, thermal, electrostatic, or video raster vs. vector. There's no discussion of special-purpose terminals such as data-collection devices. There's no discussion of such devices as remote-batch or RJE terminals. There's no discussion of connectivity - channel-attached, modem-connected, etc. I think the article could use work, but I'm not sure how to organize it. Peter Flass (talk) 22:36, 4 June 2012 (UTC)

Windows terminal emulator not provided

Running telnet in a console window has (for quite a while) used the console api to provide a passable terminal emulator. Checking now on a Windows 7, I see that telnet is an optional feature. By the way, the use of "modern" in topics such as this is a red flag indicating inaccuracies (indeed, most of the statements are unsourced, reflecting their origin in personal opinion). TEDickey (talk) 10:51, 8 September 2013 (UTC)

The suggested stackoverflow link does not address the criticism made (and by the way is not authoritative in any sense) TEDickey (talk) 15:45, 8 September 2013 (UTC)

But I also added the qualifier "ANSI" to "terminal emulator". I'm not sure what kind of terminal the Windows console does emulate, outside of MS-DOS mode (which would not count as "modern Windows"), but if it's not ANSI/VT-100 then it's not very useful, these days.--greenrd (talk) 18:09, 8 September 2013 (UTC)

The comment in the topic which you removed was for Hyperterminal, which was replaced a long time ago by the Windows telnet (since serial connections were not useful), which in turn uses the console api to provide terminal emulation. The telnet program identifies itself as "ansi". So... Windows does provide terminal emulation in this way, and has (if I recall properly) since Windows 2000. By the way, you can also provide a telnet server on Windows7 at least (noted while verifying things earlier). You should be aware that ANSI and VT-100 are not synonymous - they merely overlap substantially. TEDickey (talk) 18:22, 8 September 2013 (UTC)

If you're unfamiliar with the console api, here is one of the pages discussing it. TEDickey (talk) 18:24, 8 September 2013 (UTC)

here is mention of an old version of the telnet terminal description, from 1999. TEDickey (talk) 18:35, 8 September 2013 (UTC)

given the content of the topic as it exists, all that you can say about "ANSI" is whether the terminal uses the ANSI controls (which Windows telnet does...). So I don't see any benefit offered by your stackoverflow link - it is concerned with coloring the prompt, which is only a small part of terminal emulation. TEDickey (talk) 18:40, 8 September 2013 (UTC)

Noting recent edits emphasizing native ANSI terminal emulation bears on this issue. The "ms-vt100" entry described in ncurses' terminal database uses "ANSI" controls, just as do the randomly-selected set of examples (each of which, by the way, has one or more deficiencies with respect to ANSI and/or VT100). Aside from the obvious point that editors wish to make that Windows lacks something, there's apparently nothing to discuss here. TEDickey (talk) 19:44, 20 September 2013 (UTC)

Again, "virtual device" is probably irrelevant (or we have to drop Solaris from the list, as I recall, as well as one or more of the BSD's). Like Windows, OSX lacks a "console" which is what some of the editors are attempting to describe. It provides a terminal emulator instead. So that's half the list gone. TEDickey (talk) 20:39, 20 September 2013 (UTC)

OK, it now says

The Win32 console on Windows does not emulate a physical terminal that supports escape sequences so SSH and Telnet programs (for logging in textually to remote computers) for Windows often incorporate their own code to process escape sequences. On systems that provide terminal emulators that do support escape sequences, such as those on most Unix-like systems, this bundling is unnecessary.

Hopefully that 1) is technically correct in its description of the issue on Windows and 2) avoids randomness.

I'm not sure what the "console" is that you say some editors are attempting to describe. If you're referring to what you get if you don't run a window system, if you log into OS X as >console, it gives you a non-window-system session that I think might support some escape sequences (>console isn't working on my VMware Fusion OS X virtual machines, and I'm not about to log out on my host machine to test it). Solaris also supports such a console, as do FreeBSD, DragonFly BSD, and NetBSD and OpenBSD if you've enabled more than just "dumb". (They might not support multiple virtual consoles, but that's another matter.) Guy Harris (talk) 22:00, 20 September 2013 (UTC)

No, the issue is unresolved. The topic is slanted to prove a point, rather than noting how terminal emulators in Windows actually are supported. We could go on at length, but there's nothing factual that I could use in referring to this page. TEDickey (talk) 22:07, 20 September 2013 (UTC)

Is the current version

The Win32 console on Windows does not emulate a physical terminal that supports escape sequences so SSH and Telnet programs (for logging in textually to remote computers) for Windows, including the Telnet program bundled with some versions of Windows, often incorporate their own code to process escape sequences. The terminal emulators on most Unix-like systems, such as, for example, xterm and [[Terminal (Mac OS X)|], emulate physical terminals that support escape sequences

not such slanted, or does discussing the difference at all constitute trying to prove a point? Guy Harris (talk) 22:11, 20 September 2013 (UTC)

There's still some debris, as would be noticed by someone proofreading the current revision. For instance, the "so" in the first sentence after the tag where this discussion is introduced as indicating a limitation. A neutral phrasing would point out that the Windows console api does not itself perform terminal emulation, but that there are terminal emulators (such as the longstanding Cygwin console from 2000-2010 and the Windows telnet application) which use this api to provide terminal emulation (a difference in approach rather than a deficiency). Keep in mind that this is the Computer terminal topic, not ANSI escape code. On the positive side, OSX console is no longer mentioned (naive readers might not understand that it was unlikely to be something they would use). Also, it's probably fairly easy to source something which points out that the reason for add-on terminal emulators (which again, almost entirely are ssh or telnet clients) is for improved interoperability with various applications, or more convenient user interfaces - GUIs), while noting that analogous programs are far from lacking in the Unix/like platforms. As usual, WP:RS should bear the burden rather than editors writing an essay. TEDickey (talk) 19:32, 21 September 2013 (UTC)

I don't see what's dubious here - Win32 console does NOT provide ANY terminal emulation, and that's it. Without additional software like ansi.sys or telnet.exe etc. it is not capable of rendering any escape sequences, but only the console API calls. So, that "dubious" tag should be removed. --Arny (talk) 19:10, 27 March 2014 (UTC)

Support for escape sequences is not a sine qua non for being a terminal; the Teletype Model 33 didn't. The ADM-3A page seems to indicate that the original ADM-3 didn't, either. Guy Harris (talk) 19:53, 27 March 2014 (UTC)

Wikipedia is not a WP:RS, in either sense of the term. For example, see the terminal database entry for adm3a], which uses an escape sequence for cursor-positioning TEDickey (talk) 20:42, 27 March 2014 (UTC)

I didn't use WP as a reliable source; that's why I said "seems to indicate". I also said "original ADM-3"; the article seems to indicate that the ADM-3 didn't support cursor positioning, and that the ADM-3A added that. The entry for adm3 does not have any cursor positioning escape sequences; if that counts as a reliable source ("primary sources" be damned, I'd rather see an actual LSI manual for the ADM-3 and perhaps an LSI document indicating that cursor positioning was a Shiny New Feature in the ADM-3A), I'd say there's an RS for the claim that the ADM-3 didn't support escape sequences. Guy Harris (talk) 22:45, 27 March 2014 (UTC)

The ADM-3 Maintenance Manual, in section 3.4.1 "Remote Control Functions", doesn't say anything about the host being able to reposition the cursor arbitrarily or about an ESC from the computer having any special function. Section 4.2.5 "Cursor Generation" only speaks of moving the cursor forward and backward on the current line, and section 4.3.4 "Cursor Control Logic" also speaks of it moving only forward and backward. (The manual also refers to an "Upper/Lower Case Display Feature", so the ADM-3A page needs to be updated to indicate that the ADM-3 could display full ASCII with that option. Oh, and it also refers to the ADM-3 as a "Dumb Terminal", for what that's worth in the great "what's a dumb terminal?" debate.) Guy Harris (talk) 22:59, 27 March 2014 (UTC)

That's a maintenance manual. Information of the sort you're looking for is typically found in something with "programming" or "reference" in its title. This manual (quick read) contains only some discussion of keyboard functions that a repairman with an oscilloscope would be likely to exercise TEDickey (talk) 23:10, 27 March 2014 (UTC)

I'm quite aware that it's a maintenance manual, but it does cover more than "some discussion of keyboard functions that a repairman with an oscilloscope would be likely to exercise" - do more than just a "quick read", try looking at the sections I cited. I'll try to find a reference manual, but I'll bet it'll confirm that the ADM-3 had no support for escape sequences. Guy Harris (talk) 23:24, 27 March 2014 (UTC)

Did you read the source I provided? (I'm certain that ADM-3A supported cursor-addressing, though of course that's "only" personal experience). Bye. TEDickey (talk) 00:16, 28 March 2014 (UTC)

If you mean "did I read the terminfo entry", the answer is "yes". Did you read the terminfo entry I provided, namely the terminfo entry for the ADM-3? My original comment was "The ADM-3A page seems to indicate that the original ADM-3 didn't, either." - note the "original", and lack of an "A" following "3", in "original ADM-3". I am not saying, and have never said, that the ADM-3A had no cursor addressing; I'm saying the original ADM-3 doesn't appear (from the maintenance manual and from the terminfo entry) to have cursor addressing. Please let us speak of the ADM-3A no further; let us speak only of the original ADM-3, with only one "A" in the name, that being the "A" in "ADM". Guy Harris (talk) 01:11, 28 March 2014 (UTC)

certainly (a reminder of your interest in the original model would have been more useful than a digression regarding the maintenance manual, since adm3 has a well-known WP:RS which does not require interpretation). Back to the point on terminal capabilities, the adm3 does support crude cursor movement, because it supports screen-erasure as well as backspacing. Also back to the point, the Windows console api provides a way to implement the various suggested features, including the telnet application (see ms-vt100). The behavior is implemented by the Windows application - not by some remote host behavior. So (all the way to the top of the thread), there's a terminal emulator provided by Windows. Are there any points to discuss? TEDickey (talk) 08:02, 28 March 2014 (UTC)

References

Turing-complete

Recent edit used the term Turing-complete for this, without noticing that the issue of "bounded size" makes it inconsistent. Also, the document doesn't support a "first". Finally of course, the edit is not topical TEDickey (talk) 18:08, 9 February 2014 (UTC)

I've just added a further resource.

Furthermore EVERY physical / real-world machine has limited memory - so if you don't want to drop the idea of Turing-completeness altogether for real-world computers, it's of course an attribute whereby the principal physical limitation is understood by itself.79.230.160.93 (talk) 18:16, 9 February 2014 (UTC)

Real-world computers aren't (except in marketing literature) Turing-complete, because they're necessarily incomplete. You can undoubtedly find some dubious information to support your contention, but neither source pretends to do that. TEDickey (talk) 18:30, 9 February 2014 (UTC)

So are you going to change (for a start) the information presented in the table of the following "dubious"(?) source: History of computing hardware#Early computer characteristics? 79.230.160.93 (talk) 20:53, 9 February 2014 (UTC)

actually, there's enough misinformation on Wikipedia to keep us both occupied. But there's no point to be made in adding to it. WP:OTHERSTUFF is something you should keep in mind TEDickey (talk) 21:35, 9 February 2014 (UTC)

Well, there certainly is misinformation in the Wikipedia, but this is not part of it. My college exam on computability was several years ago - but I remember that in the lecture it was just too obvious that no physical machine is Turing-complete in a strict sense (just like there is no round circle and no right angle in the strict mathematical sense in the physical world) - but it DOES make sense to apply the attributes. Otherwise you would always have to say "theoretically Turing-complete computer" to make the distinction when comparing it to computers that are not "theoretically Turing-complete" ... well, even one over three doesn't exist for real, which I don't mention too often. 79.230.163.75 (talk) 23:07, 9 February 2014 (UTC)

The computer we're discussing was certainly limited, and only by granting unrealistic amounts of memory and tape-size could it be termed "complete". Computer science curricula might be careless about notions like infinity - or poorly understood, at the undergraduate level. TEDickey (talk) 23:55, 9 February 2014 (UTC)

This was not undergraduate level (and by the way, it's not particularly intelligent to infer poor understanding without being specific / disproving a single point made). The Turing-completeness of the other early computers was only proven years after their advent. Hans Hermes wrote an early proof of the Turing-completeness of actually built computers - practical usability was the goal of the early computers, not only of the Z3. 79.230.163.75 (talk) 00:45, 10 February 2014 (UTC)

Furthermore, there's "Turing-complete" and there's "usefully capable of being programmed to make decisions"; the paper cited for the in-principle Turing-completeness-assuming-you-can-make-a-paper-tape-as-big-as-is-necessary of the Z3 says:

I can therefore say that from an abstract theoretical perspective, the computing model of the Z3 is equivalent to the computing model of today's computers. From a practical perspective, and in the way the Z3 was really programmed, it was not equivalent to modern computers.

so the theoretical ability, given enough paper tape, to simulate a Turing machine of an arbitrary size doesn't, in and of itself, make its I/O devices worthy of being categorized as "the first computer terminal". The first terminal for a modern computer was either the buttons, switches, and output CRT of the Manchester Small-Scale Experimental Machine or the teleprinter for the Manchester Mark 1, depending on whether you consider the SSEM to be a proof-of-concept or a real example of a modern computer. The first terminal for a programmable computing device might have been the keyboard and lights of the Z3, unless there was an programmable computing device built before the Z3. Guy Harris (talk) 00:28, 10 February 2014 (UTC)

Ok, that funny link shows to me that you're critical -- have you seen that the Wikipedia article on computers says:

"Alan Turing was the first to conceptualize the modern computer"?

– the idea of the Turing machine can as well be used to build a computer, as it can be used to build a brain, or a universe-simulator, as "well" as Gödel's earlier Turing complete formalism can be used to build real computers -- is it valid to say that Turing first conceptualized the modern computer?

Apropos second part: which one will it be and why that you call the first computer, and therefore the first computer terminal -- and who has detailed information about the Z4? 79.230.163.75 (talk) 01:03, 10 February 2014 (UTC)

"is it valid to say that Turing first conceptualized the modern computer?" It depends on what you mean by "conceptualize the modern computer". A Turing machine is different from a von Neumann machine; the latter concept more closely resembles the way a modern computer actually works. Turing's paper described an abstract machine to perform computations; Gödel's paper doesn't have any similar machine notion, at least not that I can tell, nor does Church's "An Unsolvable Problem of Elementary Number Theory", so, in that sense, one could, I guess, argue that Turing conceptualized some sort of computing machine perhaps not unlike the modern computer. In what would just you just as well use either formalism "to build real computers" (not that many real computers, if any, are built using either formalism)?

Then again, if we're not restricting "conceptualizing the modern computer" to "conceptualizing a von Neumann machine", a case could be made for Charles Babbage.

"which one will it be and why that you call the first computer, and therefore the first computer terminal" I call the SSEM and Mark I the first modern computers (not the first computers, unqualified by the term "modern") because they were the first two stored-program computers where the computer could, in theory, load or write code into memory and run it (i.e., where the human operator was not, by the very architecture of the machine, obliged to hand-load a program into memory (the SSEM may not have had enough memory to hold a program that could load the next program, but that's different from a machine that doesn't run programs from memory at all, or runs them from read-only memory that has to be set up by an operator). The stored-program computer page currently says:

The University of Manchester's Small-Scale Experimental Machine (SSEM) is generally recognized as world's first electronic computer that ran a stored program—an event that occurred on 21 June 1948. However the SSEM was not regarded as full-fledged computer, more a proof of concept that was built on to produce the Manchester Mark 1 computer, which was first put to research work in April 1949. On 6 May 1949 the EDSAC in Cambridge ran its first program, and due to this event, some consider it "the first complete and fully operational regular electronic digital stored-program computer". It is sometimes claimed that the IBM SSEC, operational in January 1948, was the first stored-program computer; this claim is controversial, not least because of the hierarchical memory system of the SSEC, and because some aspects of its operations, like access to relays or tape drives, were determined by plugging.

so:

• if one considers the SSEM the first "modern computer", even though it was a bit small to be a usable computer in practice, its I/O devices would be the first terminal;
• if one considers the Mark 1 the first "modern computer" by virtue of it being big enough to be a usable computer in practice (I'm not sure quite why one would consider the EDSAC "the first complete and fully operational regular electronic digital stored-program computer" if it ran its first program in May 1949 and the Mark 1 ran its first program in April 1949, unless "ran error free for nine hours" means "it didn't finish because the machine failed during the tenth hour"), then its teleprinter would be the first terminal.

The Z4 doesn't count as a "modern computer", as it was programmed with punched tape, at least according to the Wikipedia article about it. Zuse may have come up with the idea of a stored-program computer capable of loading or generating code that it could then execute, but I don't see any indication that he implemented that idea before the Manchester people did (and the reference for that claim in the von Neumann architecture page is to a paper by the Manchester folks that doesn't mention Zuse; this page speaks of "Zuse's 1936 patent application (Z23139/GMD Nr. 005/021)", which appears to be available on-line here, where you can read the first page of the patent application for free, but that doesn't show anything about code coming from anywhere other than a tape, you need to buy the full application which says "The computation plan can also be stored so that the commands can be transmitted to the control device at the computation phase." on the page numbered 166).

If we're not going to restrict ourselves to modern computers, we could go back at least as far as the Z3, but if we're going to do that, I'd be inclined to give examples of I/O devices for other programmable computers, whether they're programmed with punched tapes or punched cards or plugboards or.... Guy Harris (talk) 03:34, 10 February 2014 (UTC)

The Turing "machine" can not be used as a blueprint to build a real computer -- even if the mathematical model is called "machine" ... that was exactly the point: that no computers are built using either formalism. ///

I considered most of these valid points and they surely speak for the computers you mentioned (the Z3 did of course not store programs internally in electronic memory -- but it does implement the stored program concept) ... there are also different characteristics of a modern computer -- referring to the modern use of floating point arithmetic, the Z3 was actually closer. The "Optimizing Compilers for Modern Architectures" book by Randy Allen and Ken Kennedy includes an interesting Figure with a timeline showing Flops/s of the fastest computers, roughly every decade a jump -- from 1KFlops/s (UNIVAC 1) to 1MFlop/s (CDC 6600) and so on. The Z3 is not shown, but it fits: 1 Flop/s a decade earlier.

To give more examples of other I/O devices of early computing systems like you suggest seems to be the best way of handling this history, making it once more clear, that technological progress is usually a gradual evolution. 79.230.128.96 (talk) 10:46, 10 February 2014 (UTC)

The Z3 was programmable but it wasn't a stored program computer, according to the stored program computer article and the citation for that article's definition of "stored program computer". It couldn't change its own programs - the user had to change the tape.

As for other characteristics of a modern computer, floating point didn't become near-ubiquitous in modern mainframes until the 1970's (the "scientific instruction set" was an add-on option for the low-end System/360's, for example), in modern minicomputers until the late 1970's or 1980's (a number of PDP-11s, for example, either had no floating point or required an add-on floating point processor or floating-point microcode), and modern microcomputers until somewhere in the 1980's or 1990's (floating point wasn't built into Motorola 68000 family processors until the 68040, it wasn't built into x86 processors until the Intel 80486, etc., and, while engineering workstations might have included floating-point coprocessors for those CPUs, lower-end personal computers might not have), but the stored-program concept was in almost all commercial computers of the early 1950's (the exceptions were a few computes programmed with plugboards).

If you don't have floating-point hardware, you can simulate it in software, as was done in a number of minicomputers, but if you can't add new code from a program, the only way you can do that in software is to have the code running on the machine be an interpreter for another form of code, at which point the latter form of code is the real machine code - the other code could be thought of as microcode. Were there any such programs for the Z3? If not, there's no way that I would ever consider it a stored program computer.

The Z3 was (as far as I know) the first programmable computer, so it can claim pride of place there; there's no need to attempt to give it pride of place in areas where it doesn't deserve it, such as being the first stored program computer. Konrad Zuse may have come up with the idea of storing instructions in memory that could be written by the computer, but there's no indication that he was the first to implement that idea.

In any case, that has little to do with computer terminals, so, if historical details about the terminals for early computers are topical, and citations can be found for information about them, describing the terminals for those early computers, without talking about attributes of the Z3 not of interest in this article (such as its use of binary arithmetic - decimal computers had terminals as well - or the hypothetical possibility of having it, for a given value of M, be able to simulate a Turing machine with a tape of size M), might be useful. Guy Harris (talk) 20:37, 10 February 2014 (UTC)

Granted, that was my error -- Zuse only wrote about the concept of the "freier Rechenplan" [i.e. free computation plan / free program], with self-modifying code in connection to his programming language Plankalkül -- but he did not implement it. I just found quotations concerning this idea and Zuse --

Friedrich L. Bauer: "His visionary ideas (live programs) which were only to be published years afterwards aimed at the right practical direction but were never implemented by him." (Original: "Seine erst Jahre später publizierten visionären Ideen (Lebendige Rechenpläne) zielten in die richtige praktische Richtung, wurden von ihm aber nie verwirklicht. [1])

And Zuse wrote in his memoirs: "During the war it would have barely been possible to build efficient stored program devices anyway." [Original: "Während des Krieges wäre es freilich ohnehin kaum möglich gewesen, leistungsfähige Geräte mit Speicherprogrammen zu bauen." in:Der Computer - Mein Lebenswerk, Berlin, 5th edition, page 78]

Now back to the topic, summa summarum the development of the universal computer was a gradual process -- and practical universality (ease of programmability, size of memory etc.) was gradually improved. The "theoretical side", i.e. (theoretical) Turing completeness was proven only later on (for the various early computers) anyway.

The definition of computer terminal in this very article does not demand a stored program computer for a computer terminal -- it's an (quote) "electronic or electromechanical hardware device that is used for entering data into, and displaying data from, a computer or a computing system" ... which reminds me of the Z3:

Z3 article: "Input and Output was facilitated by ... special keyboard and a row of lamps to show results".

Supplementing the sentence I added to the article in the first place with information about other early computer terminals would of course put it into proper context. 79.230.128.215 (talk) 13:33, 11 February 2014 (UTC)

this link appears to be a copy of the cited paper (the given doi is WP:PAYWALL not generally accessible), and doesn't differ from the abstract. It doesn't have a corresponding section for the hypothetical "computer terminal" which could plausibly be used to make this thread topical TEDickey (talk) 01:08, 10 February 2014 (UTC)

This very article which we’re dealing with here says:

"A computer terminal is an electronic or electromechanical hardware device that is used for entering data into, and displaying data from, a computer or a computing system."

I've seen the replica of the Z3 in the museum, and I also saw the computer terminal -- it's not hypothetical. 79.230.163.75 (talk) 01:18, 10 February 2014 (UTC)

oh - which of your provided sources said that was a computer terminal? (We're only considering reliable sources; personal experience doesn't count) TEDickey (talk) 01:26, 10 February 2014 (UTC)

The introductory (and obvious) sentence which I quoted in my last post from this very article also has also no explicit reference ...

The frame of the (let's call it) terminal of the Z3 replica was wooden, as we both can see in the photograph and which I saw for real -- but as long as there is no source which explicitly states that -- we can consider it hypothetical, i.e. if personal thinking doesn't count ... 79.230.128.96 (talk) 10:51, 10 February 2014 (UTC)

Difference from Computer?

This should be brought clearly in the opener, I think... The diff between Computer in C.terminal should be brought clear at the start... Ben-Natan (talk) 17:08, 18 March 2015 (UTC)

Unclear wording

The following is unclear to me: "Early terminals were inexpensive devices but very slow compared to punched cards or paper tape for input" The following for example would be clearer (if it is what was meant): Early terminals were inexpensive input-only devices and were very slow compared to punched card or paper tape devices. Seipher (talk) 17:33, 20 February 2016 (UTC)

Well, I guess an input-only terminal doesn't make sense either, so my suggestion is not good either. Seipher (talk) 17:38, 20 February 2016 (UTC)

Rather "Early terminals were inexpensive. In contrast to punched card or paper tape, terminals were low-speed devices, capable of no more than 10-30 characters per second." TEDickey (talk) 20:19, 20 February 2016 (UTC)

By the way, the low speed applied whether for input or output. There were actually phone modems handling 300 baud (less than 30 characters per second). You might be able to find useful sources for this. TEDickey (talk) 20:22, 20 February 2016 (UTC)

300 baud? What about 110 baud ? (which is not as (s)low as it could go) Pi314m (talk) 21:11, 13 March 2019 (UTC)

See my comment: 10-30 cps. If you have a 100 baud modem (not terminal) to discuss, a reliable source for that aspect is a starting point for discussion TEDickey (talk) 21:40, 13 March 2019 (UTC)

Add Thin clients

The following discussion is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.

---

• We need to add more references to thin clients as they are the only remaining computer terminals used today. — Preceding unsigned comment added by 104.228.101.152 (talk) 23:50, 17 December 2016 (UTC)

• No to proposed merger (Thin Client -> Computer terminal).
  The first sentence of Thin Client says

"A thin client is a lightweight computer built to connect to a server from a remote location."

A genuine physical DEC VT100 -- not an emulator -- is a computer?

Why not merge bus and trolley?

• Gas/Electric
• Freedom-of-the-road/Hard"wired" path

Oops... Somebody STOMPED on the Trolley, and the article is named Trolleybus!
I say:

DO NOT merge. Do NOT hop on the Merger Trolley. Articles on emulators should not be confused with articles on physical devices. Pi314m (talk) 21:29, 5 November 2017 (UTC)

"A genuine physical DEC VT100 -- not an emulator -- is a computer?" Well, if the thin client runs only the software with which it ships, with no ability to run Real Applications(TM), then it's somewhat like a VT100, with its embedded 8080A (see sheet A3 of A4) running the software that implements the VT100ness of the terminal. Guy Harris (talk) 22:55, 5 November 2017 (UTC)

The discussion above is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.

4-bits doesn't give 64 colors

64 is 2⁶, while 4 bits would be 16. Perhaps that statement was a cut/paste from something which made more sense in the original TEDickey (talk) 02:17, 12 November 2017 (UTC)

So I took it out. Giving the number of bits was typical gassy Wikipedia padding. And as so often the case, wrong padding, to boot. --Wtshymanski (talk) 02:25, 12 November 2017 (UTC)

For what it's worth, the WY-370 Programmer's Guide says, in Appendix G "Programming in Wyse 350 Personality":

Five display attributes-dim, reverse, underline, blink, and blank-can be assigned, individually or in combination, to characters or to areas of the screen.

Each attnbute or attribute combination is associated to one of four colors from the terminal's current foreground color palette. You can select from 16 premixed palettes, or you can create your own palettes from any of the terminal's 64 colors.}}

so "it's complicated", but I don't see anything about "4-bit" color there.

(The WY-370 is apparently a terminal with its own X3.64 mode, plus modes for other X3.64 terminals such as the VT220 and a pile of non-X3.64 terminals including the WY-350.) Guy Harris (talk) 03:38, 12 November 2017 (UTC)

tesla czechoslovakia

Some products from Tesla CS should be mentioned. Text terminals with graphical mode. — Preceding unsigned comment added by 88.80.224.229 (talk) 23:33, 12 December 2017 (UTC)

Date format

Hello. The date template i.e. "Use dmy dates|date=May 2012" was just deleted from this article. Such templates usually lurk at the top of more recent articles, although a number of them may still be found placed at the bottom near the categories (which was the case here). This edit simply moved it from the bottom to the top, so if the article's formatting doesn't seem match the template anymore, may I suggest simply reviewing the article to match (as deleting historic templates could be misconstrued to indicate an editing bias that is different from the established history of the article). Cheers. JabberJaw (talk) 08:29, 9 December 2018 (UTC)

That template was introduced in this edit, which had the comment "move content from Editing Terminal (telecommunication)". The text moved had one count 'em one date in that format, in the "Directive 1999/5/EC of the European Parliament and of the Council of 9 March 1999 on radio equipment and telecommunications terminal equipment and the mutual recognition of their conformity (R&TTE Directive)" reference, where it was part of the title and thus not subject to modification to fit a particular date format.

The version prior to that format had one count 'em one date, in the "External links" section, in the format "2010-05-23".

So the "established history of the article" doesn't say anything about date formats, and the removal of the template is entirely appropriate. HAND. Guy Harris (talk) 10:45, 9 December 2018 (UTC)

$15,000 terminal

The text about the "plans to build a video terminal for $15,000" that was described as "proved too ambitious" is available here Pi314m (talk) 21:39, 13 March 2019 (UTC)

Early VDUs, FSVO early

Early VDUs were not called glass TTYs; the character oriented ASCII CRT terminals came later. I'm not sure what was around in the 1950s, but in the 1960s you had graphics terminal and block-oriented terminals with proprietary interfaces. As I recall, glass TTY entered the lexicon in the mid 1970s. Shmuel (Seymour J.) Metz Username:Chatul (talk) 15:31, 30 August 2020 (UTC)

You are talking about, for example, IBM 2260. Did IBM even use the term "TTY" or "teletype"? I thought "teletype" was a trademark of Teletype Corporation, and tty an abbreviation of that trademark, so IBM wouldn't use its competitor's trademark for its own products. Since AT&T owned both Teletype and Bell Labs, it is unsurprising Unix spread a term derived from an AT&T-subsidary's trademark through the computing industry (and, combined with technological obsolescence, contributed to its genericide). Later, in the 1980s, IBM started using the term "tty" in IBM Unix variants, such as AIX and OS/390 USS, but by then physical teletypes were obsolete, and Teletype corporation was defunct, so IBM's use of the term in the 1980s and later would not have posed the kind of legal issues that using it in the 1960s would have. SJK (talk) 10:24, 1 September 2020 (UTC)

I'm talking about, e.g., 2250, 2260, 3270, comparable devices from other manufacturers. I've never seen anybody refer to anything other than a character oriented ASCII terminal with an asynchronous interface as a glass TTY.

IBM used the term TTY for an asynchronous terminal compatible with, e.g., ASR 33. IBM's various Unix systems used Unix nomenclature, but outside of a Unix context IBM never used tty to refer to a block mode terminal.

Also, there were CRT terminals before either the 2260 or the ASR 33. Nobody called them glass ttys. Shmuel (Seymour J.) Metz Username:Chatul (talk) 15:45, 1 September 2020 (UTC)

I have significantly revised the VDU section in a way that I think makes the usage of "glass tty" clearer". Esr (talk) 18:31, 23 May 2021 (UTC)

@Esr: I like some of the changes, but why did you delete Early VDUs were typically designed for displaying graphical data rather than just text. from Computer terminal#Early VDUs? They were using CRT displays a decade before the 2260 and Uniscope. Shmuel (Seymour J.) Metz Username:Chatul (talk) 19:06, 23 May 2021 (UTC)

If so, examples should be given in the article. Guy Harris (talk) 20:39, 23 May 2021 (UTC)

Well, in addition to the IBM 780, both DEC and MIT had graphics displays. In fact, UNIVAC had CRT displays in the 1950s, on, e.g., the ERA 1101, as did such military systems as SAGE and BUIC. Shmuel (Seymour J.) Metz Username:Chatul (talk) 21:17, 23 May 2021 (UTC)

So add those to the article in the Computer terminal#Early VDUs section. Guy Harris (talk) 21:36, 23 May 2021 (UTC)

Hardcopy terminals

Should the article discuss the common technologies for hardcopy terminals, e.g.,

• Typebar
• Typewheel
• Selectric ("golfball")
• Daisy wheel
• Spinwriter
• Impact dot matrix
• Thermal dot matrix, e.g., TI Silent 700
• Inkjet

Should the article discuss line printers for remote batch terminals?

• Print bars
• Print drum
• Chain
• Train
• Band
• Line matrix printer

Should the article discuss the market for clones of, e,g, IBM 2741? Shmuel (Seymour J.) Metz Username:Chatul (talk) 13:45, 18 January 2021 (UTC)

Don't forget typewheels as in the Teletype Model 33 and typeboxes or whatever they're called in the Model 35, as well as ordinary typewriters such as the console on the IBM 1620.

And, yes, it should discuss them, given that this page is titled "computer terminal", not "video display terminal". Guy Harris (talk) 20:50, 18 January 2021 (UTC)

I've updated the list with text in <u>...</u>, but I'm not knowledgeable about all of the technologies. Also, where should the remote batch terminals go? Shmuel (Seymour J.) Metz Username:Chatul (talk) 22:16, 18 January 2021 (UTC)

Given that the article is titled "computer terminal", not "interactive computer terminal", I'd say that remote batch terminals belong here; I'd put them adjacent to the hard-copy terminals section. Guy Harris (talk) 22:47, 18 January 2021 (UTC)

Organization of article

Currently a lot of information about various technologies used in terminals is located in #History. I believe that there should be a separate taxonomy section classifying the types of terminals and describing the various technologies used, with the history section limited to identifying specific terminals, their dates and their technologies. 13:46, 19 January 2021 (UTC)Shmuel (Seymour J.) Metz Username:Chatul (talk)

Short description

@Whiteguru: A recent edit changed the short description from {{short description|Computer input/output device; an electronic or electromechanical hardware device that is used for entering data into, and displaying data from, a computer or a computing system update programming}} to {{Short description|Computer input/output device}}. However, most input/output devices are not terminals, e.g., tape drives, disk drives. How about {{short description|An electronic or electromechanical input/output device that is used by an operator to enter data into, and receive data from, a computer or a computing system}}? --Shmuel (Seymour J.) Metz Username:Chatul (talk) 20:21, 7 July 2021 (UTC)

@Chatul: With short descriptions, we have a situation where we are aiming to have a maximum of 40 characters. The driving reason is that the short description is displayed on the mobile access to the article in a search result. 65% of access to Wikipedia is now via mobile devices or tablets. So we have that objective to display a short description that is readable on the mobile device. Descriptions over 40 characters get chopped off. With your forbearance, I ask, "What would you consider as apt?" --Whiteguru (talk) 22:21, 7 July 2021 (UTC)

@Whiteguru: @Chatul: "Computer input/output device for users". 38 characters. Guy Harris (talk) 22:46, 7 July 2021 (UTC)

I like it, at least given the conflict between accuracy and brevity. --Shmuel (Seymour J.) Metz Username:Chatul (talk) 23:11, 7 July 2021 (UTC)

Accuracy and brevity rules! Well done! --Whiteguru (talk) 01:50, 8 July 2021 (UTC)

Too bad the article is longer than 40 characters; those poor tablet and mobile device users will never get to see all our Brillian Prose (TM). --Wtshymanski (talk) 21:52, 8 July 2021 (UTC)

Speed

Shouldn't the article discuss speed in bits/second? Giving speed in characters/second makes it difficult to compare, e.g., the 5-level TTY 28 with the 7-level TTY 33, since the former must inject FIGS and LTRS to switch between digits and letters. Describing both as 10 CPS would create the false impression that they have the same performance. --Shmuel (Seymour J.) Metz Username:Chatul (talk) 15:27, 2 March 2022 (UTC)

Unclear VDU explanation

"Block-mode terminals", "Character-mode devices". Sorry, that might seem obvious for the guy that wrote it, but means nothing to me. Ignacio.Agulló (talk) 00:37, 4 August 2022 (UTC)

"Block-mode" and "character-mode" are explained in Computer terminal § Modes, but that comes after Computer terminal § History, which is the first place those terms are used. Perhaps the History section needs to be moved after Modes. (And perhaps we need to use the same terminology consistently, e.g. "XXX-mode" vs "XXX mode" and "XXX-mode" vs "XXX-oriented".) Guy Harris (talk) 00:58, 4 August 2022 (UTC)

Misnomer?

Today, most PC telnet clients provide emulation of the most common terminal, the DEC VT100...

Uh, the VT-100 was not “the most common terminal.”  That honor would belong to the WYSE 60, which was installed in vast numbers in the years after its introduction.  Few VT-100s were used in installations that didn’t have a DEC mini.  I dimly recall one estimate that said for every VT-100 in use, at least 10 WYSE 60s were in use.

216.152.18.132 (talk) 02:55, 24 April 2024 (UTC)

No, not a misnomer, except perhaps in the fourth, non-standard, sense. It may be an incorrect claim, however. I'll ask for a citation and, if none shows up, turn it into "provide emulation of the DEC VT100...". Guy Harris (talk) 03:20, 24 April 2024 (UTC)

BTW, two “personalities” offered in the WYSE 60 were VT-75 and VT-100.  WYSE even sold a specific keyboard for users who wanted the VT-style layout.  That made it possible for DEC mini users to escape the vendor lock-in that DEC had created with the VT series—the WYSE 60 was cheaper to purchase, used less power and desk space, and (in my opinion) looked less clunky than the DEC terminals.  :)

As for terminal emulation on a PC (better described as “simulation”), there are several third-party packages that support a wide variety of terminals other than the VT series.  One with which I am familiar is Dynacomm, which even supports the old IBM terminals that used to be connected to S360 and S370 mainframes with SNA (can’t imagine anyone uses SNA anymore).

216.152.18.132 (talk) 06:31, 19 November 2024 (UTC)

Can you provide a citation or some background materials? The young generation of programmers' knowledge of this part of computing history is especially insufficient. Hym3242 (talk) 09:43, 19 November 2024 (UTC)

It would be nice to have citations aimed at a general audience for all of:

1. Physical terminals
2. Cluster controllers
   1. Coax and twinax
3. Means of connecting terminals
   1. Current loop, RS-232 and similar technologies
      1. Asynchronous
      2. Synchronous
   2. LAN
   3. Channel attached controller
4. Physical terminals compatible with competing terminals
5. PC software simulating terminals
   1. Telnet and TN3270

Of course, more technical citations should remain.

If there are wiki articles with relevant background, it would be nice to have links to them as well.

There have been enough asynchronous terminal simulators to warrant a separate article. The number of 2780 and 3270 simulators, while smaller, is still significant. The pricing models have been all over the landscap, from completely closed to open source. -- Shmuel (Seymour J.) Metz Username:Chatul (talk) 13:26, 19 November 2024 (UTC)

ASR

@Bachcell: Edit permalink/1224858323 disassociates the reference to paper tape from the term ASR — Preceding unsigned comment added by Chatul (talk • contribs) 12:19, 21 May 2024 (UTC)

Perhaps the intent was to separate "has a paper tape reader and punch" from the description of Teletype models, because other terminals, such as Flexowriters, also supported paper tape. In this edit, I added to the sentence about paper tape a clause noting that the ASR Teletype models were examples of teleprinters with paper tape support. Guy Harris (talk) 21:56, 22 May 2024 (UTC)

That works for me. Thanks.

Should the text spell out ASR and KSR on first use? -- Shmuel (Seymour J.) Metz Username:Chatul (talk) 12:22, 23 May 2024 (UTC)

It already does:

Early user terminals connected to computers were, like the Flexowriter, electromechanical teleprinters/teletypewriters (TeleTYpewriter, TTY), such as the Teletype Model 33, originally used for telegraphy; early Teletypes were typically configured as Keyboard Send-Receive (KSR) or Automatic Send-Receive (ASR). Some, such as the ASR Teletype models, included a paper tape reader and punch which could record output such as a program listing and then re-entered with the tape reader at a different location.

BTW, that could be read as saying that the Flexowriter isn't a "user terminal". It was certainly used as the (console) terminal for some single-user systems, dating back at least to the Whirlwind I, but perhaps it wasn't used for time-sharing. Guy Harris (talk) 20:18, 23 May 2024 (UTC)

That comes later. Should it spell it out at the point of first reference? -- Shmuel (Seymour J.) Metz Username:Chatul (talk) 20:51, 23 May 2024 (UTC)

Later than what? Is there a reference to "ASR" or "KSR" prior to Computer terminal § Hard-copy terminals? If so, where is it? Does the image of the TTY Model 33 show up before the first paragraph of that section, rather than to the right of that section, if, for example, the page is read in a narrow window? Guy Harris (talk) 22:43, 28 May 2024 (UTC)

Sorry, senior moment.

No, I don't believe that the image counts.

Should I add anchors for ASR, KSR and RO to Teletype Corporation#Teletype Corporation and link to those? -- Shmuel (Seymour J.) Metz Username:Chatul (talk) 10:11, 29 May 2024 (UTC)

Yes, that might be helpful (although this page doesn't mention the RO models - they can be printers, but not interactive terminals, as they can't provide input). Guy Harris (talk) 18:49, 29 May 2024 (UTC)

Done -- Shmuel (Seymour J.) Metz Username:Chatul (talk) 15:18, 30 May 2024 (UTC)

Notes