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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?

I ask because it's not in the document with the ASCII standard I found.

Pictures attached of what I'm referring to.

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    You're aware that posting the same question on various SE sites at the same time is considered spamming? If you want to have it moved, aking for doing so would be the right way - not duplicate it. – Raffzahn Oct 27 '19 at 21:51
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The ASCII standard doesn’t explain how it was constructed, but Charles E. Mackenzie’s Coded Character Sets, History and Development does. Section 14.9 covers control characters. When building the 1963 version of the standard, a number of control characters were deemed essential for transmission control, and these were placed in the code space in such a way as to minimise the risk of transmission corruption; in addition, a few “format effectors” (tabs, line feed, form feed, carriage return), code extensions (Escape etc.), and some miscellaneous control characters (bell etc.) were included. The remaining characters were assigned general meanings but nothing specific (device control and separators). The addition of the lower-case alphabet in the 1967 standard meant that some control characters had to be moved; others were renamed, or removed, and quite a few were added (including backspace, EOT...). The 1967 standard is the version still in use today.

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I'm reviewing the historical original ASCII standard.

The 1963 iteration was still mostly TTY orientated and got only partly adaption with TTYs. Computer use was incosistent, especially since most logical control characters were not standardized at all.

There are many control characters. Does anyone know the history of them

Except for the Sn series they're all TTY related and direct descendants of other prior codes and applications (mostly ITA2 as base and FIELDATA for computer use). You might want to consultate other teleprinter setups and manufacturers here, as well as their protocols.

and where finite state machines that made use of them may be documented?

Mind to explain what kind of purpose the a state machine you're asking for should have? Without that question doesn't make much sense.

I ask because it's not in the document with the ASCII standard I found.

As it's not any business of the standard? Keep in mind, back than standards were made for practical use by engineers, not theoretical clean room definitions. All control codes used are of obvious meaning to a 1960s user, so no need for much explanation, beside spelling their function that is.

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  • I think of a teletype as a kind of "finite state machine". But that's probably not what the OP intended. – Walter Mitty Oct 27 '19 at 22:21
  • @WalterMitty Jup, would be a possible interpretation, but even in this case, it needs more information about protocol and application - like with in-band or out-of-band dialing. I love state machines, but they are a tool, not more and especially not in themself. – Raffzahn Oct 27 '19 at 22:30

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