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92 votes
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Exactly what color was the text on monochrome terminals with green-on-black and amber-on-black screens?

Based on the phosphors used for green and amber screens, this answer on Super User gives the following values: i.e. #FFB000 for dark amber, #FFCC00 for light amber, and variations around #33FF33 or #...
88 votes
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What protocol do Teletypes use?

Aside from the character code (which I'll get to later) about the only "protocol" has to do with character framing, until very late in Teletype machines' timeline. Quick summary: The signal ...
Jamie Hanrahan's user avatar
61 votes
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History of Ctrl-S and Ctrl-Q for flow control

Which OS was the first to use Ctrl-S and Ctrl-Q on the console for pause and continue? TL;DR; It's been developed independently of anything one might call an OS (*1). It's (nowadays) called Software ...
Raffzahn's user avatar
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57 votes

Exactly what color was the text on monochrome terminals with green-on-black and amber-on-black screens?

If your aim is to recreate more closely the effect of an old CRT (at the expense of readability), whatever color you choose based on the previous answer, you should consider using a very bright (...
dim's user avatar
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47 votes

What is a Dumb Terminal?

Like any non-hard term, the label 'dumb' terminal is not only open to interpretation, but also used in different ways over time. Even more so for making others look bad (dumb) or one's own products ...
Raffzahn's user avatar
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43 votes
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How was the blinking terminal cursor invented?

The cursor is needed on a CRT raster display because otherwise it's hard to know where the next character will appear. On a teletype or teleprinter, you know where the next character will be printed ...
Ken Gober's user avatar
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42 votes

Were there ever any dumb terminals in a portable form factor?

if there was ever a case of a company making some sort of serial ASCII terminal, but in a portable factor Well, it all depends on the definition of dumb, portable and terminal. Let's go with the most ...
Raffzahn's user avatar
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39 votes
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What mid-1970s to mid-1980s home computers had their graphics characters added to Unicode 13?

The new additions mentioned are mostly to be found in the new Symbols for Legacy Computing block (PDF link) covering the 1FB00–1FBFF codepoint range. This block includes: a large number of BLOCK ...
natevw's user avatar
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35 votes
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When you type on a computer terminal, how are the characters displayed on the screen?

Terminals fall into two broad categories: Character-at-a-time Line- or Screen-at-a-time The VT100 is a character-at-a-time terminal, which means that when you press a key on the keyboard, a ...
Ken Gober's user avatar
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32 votes
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What is the difference between the "Return" and "Enter" keys in the VT100 terminal?

Under normal circumstances, there is no difference (RETURN and ENTER will send CR or CR LF as configured by the New Line Mode). However, there is a mode called "keypad application mode" ...
Greg Hewgill's user avatar
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32 votes
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How and what did it mean to connect to ARPANET from home?

You dial in with a terminal to a TIP (Terminal Interface Processor), which then offers a simple command interface to connect you to some host machine. Living Internet web site Wikipedia Functionally, ...
dave's user avatar
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32 votes

Why did the VT100 terminal have to be connected to a host computer if it already had a processor?

"Having a processor" is not sufficient for something to be a general purpose computing device. The VT100 was designed for a specific purpose, and adding more features like storage and I/O ...
Greg Hewgill's user avatar
  • 7,009
30 votes

Did terminals (e.g. VT100) require a terminal driver on the host computer?

Different terminals didn’t (and don’t) use different kernel-level drivers. In Unix-style systems, the kernel does provide some terminal-related features, called line disciplines and the TTY layer ...
Stephen Kitt's user avatar
27 votes
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How did early video terminals convert ASCII into font graphics?

Video Terminals I understand the term "video terminal" to refer to things like the DEC VT-100 or Lear-Siegler ADM-3A. They get characters (typically ASCII-encoded) over a serial line from ...
Ralf Kleberhoff's user avatar
27 votes

What was the first OS with the type-ahead capability from a dumb terminal?

MS-DOS did not have a type-ahead feature, because that function was provided by the BIOS. A typical PC BIOS had a 15 or 16 character typeahead buffer, where keystrokes would be queued until something (...
Greg Hewgill's user avatar
  • 7,009
24 votes

History of Ctrl-S and Ctrl-Q for flow control

First OS is hard to say. The codes go back to the 1960s with the Teletype Model 33. I have a hunch the original usage was not part of an operating system but at a lower level. In later times, ...
manassehkatz-Moving 2 Codidact's user avatar
24 votes
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Emulate a text-mode DOS program using a Unix terminal

As ecm wrote, DOSEMU supports this, using -t or -dumb. This works with the original DOSEMU and DOSEMU2. -dumb runs DOS programs in “dumb” terminal mode, where output goes to DOSEMU’s standard output ...
Stephen Kitt's user avatar
23 votes
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What was the largest resolution supported by terminal escape codes?

There is no limit, at least not by definition. And more so, not something across all terminals ever made. Most prominent nowadays (*1) is the so-called ANSI sequences standard - understood by next to ...
Raffzahn's user avatar
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23 votes

How was the blinking terminal cursor invented?

In 1967, a magazine article, cited a few times in the decade afterwards, said: The cursor (entry marker) identifies the next display position to be entered. The cursor continually blinks three to ...
JdeBP's user avatar
  • 2,288
22 votes

Exactly what color was the text on monochrome terminals with green-on-black and amber-on-black screens?

I dimly recall these two specific hue frequencies were picked because the human eye focuses them the most accurately. Other colors would focus in front of or behind the retina. A modern RGB green is ...
Swiss Frank's user avatar
21 votes

Why is the serial port driver named "/dev/ttyS#"?

TL;DR: Until Unix v7, if you wanted to be able to use a serial port for terminal logins, it had to have a name starting with "/dev/tty". At the time the first Unix systems were developed, it was ...
Ken Gober's user avatar
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21 votes
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Advantage of RS-232 over 20mA current loop

TL;DR: It's a classic case of technological advancement vs. installed base In the early days of electricity-based communication (i.e., telegraph and later TTY) there was no way to detect a voltage and,...
Raffzahn's user avatar
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21 votes

What is a Dumb Terminal?

I suggest a somewhat different definition of dumb terminal. While clearly some terminals were smarter than others, I don't think things such as programmable selection of fonts and colors, direct ...
manassehkatz-Moving 2 Codidact's user avatar
20 votes
Accepted

In this movie I see a strange cable for terminal connection, what kind of connection is this?

It's probably much like the Ampex 210. See page 2-7 of the Ampex 210 Operating Manual. Based on the position, it would be the primary RS232S port connected to a ribbon cable. Ribbon cables were used ...
HABO's user avatar
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19 votes
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Different escape codes for the same keyboard keys -- where did they come from?

It's one single source, not multiple vendors. Nearly all of what you mention actually comes from one source, DEC VTs. The various different control sequences generated by the function, cursor, ...
JdeBP's user avatar
  • 2,288
19 votes

In this movie I see a strange cable for terminal connection, what kind of connection is this?

25-wire ribbon cables were quite common for serial ports. See, for example, the classic breakout box: I preferred using cables and adapters. Typically I would use 6-wire cables (ground, TX, RX, CTS, ...
manassehkatz-Moving 2 Codidact's user avatar
17 votes
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How did SABRE work interactively without screens?

Wikipedia, unsurprisingly, gives incomplete information. A number of important new technologies were developed as part of the five-year R&D of SABRE, including a disk drive capable of storing ...
Davislor's user avatar
  • 8,745
17 votes

Were there ever any dumb terminals in a portable form factor?

The Termiflex was a handheld terminal that was introduced in 1979. It was very cumbersome to operate as it had a very limited keyboard and could only display a few characters at a time. It looks like ...
Kevin White's user avatar
16 votes
Accepted

What is the history of the Intel 8275 video controller?

Why it has been designed, where it has been used? Its target market was terminals. The 8275 is a very versatile logic chip for generating text displays (*1) so nearly any terminal format of that ...
Raffzahn's user avatar
  • 225k
16 votes

Advantage of RS-232 over 20mA current loop

The current loop goes all the way back to classic telegraphy. If there's current flowing, then that's one state. If there's no current, then that's another state. It's as simple as it can be. You ...
RETRAC's user avatar
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