Questions tagged [ascii]

The 7-bit ASCII character set, including control codes. DO NOT USE for binary-coded decimal; consider using [character-sets] instead for extensions of ASCII. See tag wiki.

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1 answer

Why was PETSCII based on an obsolete version of ASCII?

PETSCII (sometimes PETASCII) is the character set developed by Commodore for use in its microcomputers. The first of these, the PET, started to be developed in early 1976. Why, then, did Commodore ...
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5 votes
1 answer

Why ASCII paper tape has lower bit punched from the narrow side?

ASCII was presented on paper tape where the lower 5 bits cross sprocket holes as following While FIELDATA chose the other way I found placing the higher, flag bits at the narrow side appealing, ...
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3 votes
3 answers

Are the control characters any useful nowadays? [closed]

I asked this question on Super User, but the community at the site told me to redirect to this site. If this is again an off-topic question, do not blame me please! I am sorry if the control ...
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9 votes
1 answer

When did tabs start defaulting to 8 columns?

The ASCII horizontal tab character defaults to 8 columns, which is unfortunate because it's too wide for indenting block structured languages (at least to most people's taste, acknowledging Linus ...
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16 votes
3 answers

C64/PETSCII block graphic symbol: was there ever a logical reason for their "ASCII" codes?

You know those block graphic symbols that allows you to draw lines, corners, intersections, fine bar charts, etc. they are useful and one can do a lot of stuff, but their code arrangements always ...
13 votes
5 answers

When did IBM start to use ASCII?

I’m trying to figure out when IBM switched to ASCII and when ASCII became a worldwide standard. Moreover, did IBM make ASCII standard worldwide? What I have found: According to Wikipedia, IBM System /...
5 votes
5 answers

How does the shift key in a keyboard work?

The "shift" key on a keyboard is different from other keys as it can edit the outputs of the other keys on the keyboard. But how does it do it? I have one hypothesis on how the shift key does what it ...
1 vote
2 answers

ASCII ASA X3.4-1963 and Finite State Machines?

I'm reviewing the historical original ASCII standard. There are many control characters. Does anyone know the history of them and where finite state machines that made use of them may be documented? ...
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25 votes
2 answers

What was the ASCII end of medium (EM) character intended to be used for?

I can find information about how characters were used to structure transmissions in general, and I can find information about transmission characters which are still commonly used today, though ...
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31 votes
2 answers

Why wasn't EBCDIC designed with contiguous alphanumeric characters?

Inspired by this question on ASCII, I have wondered similar things about EBCDIC. At work we have an EBCDIC file that gets sent to a mainframe (I presume an IBM one) and to view it on my laptop I ...
74 votes
7 answers

Why wasn't ASCII designed with a contiguous alphanumeric character order?

Anyone who has dealt with strings at a low level (e.g., writing a parser in C), knows that doing so tends to involve frequent checks of—either manually, or through isalpha(), isalnum(), etc—whether a ...
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7 votes
4 answers

What characters which were in use at the time were excluded from ASCII?

The American Standard Code for Information Interchange is a 7-bit character encoding. Work on the standard began in 1960 and the first edition was published in 1963. The standard attempted to ...
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45 votes
3 answers

Why are the symbols on the number keys of PC & Mac keyboards different to ASCII keyboards?

On a US-layout PC keyboard, the symbols above the number keys are as follows: Whereas the keyboard on an Apple II is different: Note, for example, the '(' and ')' symbols are now above 8 and 9, and '...
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35 votes
4 answers

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? I first discovered Ctrl-S in IBM PC DOS 1.1.
14 votes
1 answer

What's the deal with System/360's "USASCII" mode?

The original System/360 architecture had a bit in the Program Status Word that would select an "USASCII" mode rather than the usual EBCDIC. Setting this bit changed how the BCD arithmetic operations ...
45 votes
8 answers

Executable ASCII files before x86?

I've known about a technique allowing to bootstrap arbitrary 16-bit x86 code from a subset of instructions representable as printable ASCII bytes since the early 1990s. The first example of an ASCII ...
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7 votes
2 answers

What file systems / encapsulation formats used ASCII control characters?

Most of the ASCII character codes make sense in the context of data transmission, e.g. ␄, ␗, ␖ (end of transmission, end of transmission block, synchronisation). However, there are also codes such as ␜...
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