ECMA-17: Graphical representation of control characters (1968) [pdf] | Hacker News Reader

ECMA-17: Graphical representation of control characters (1968) [pdf]

ecma-international.org

93 pointssusam20 comments

It would be interesting to read how they decided on these specific symbols, or if that knowledge is lost to time. I feel like sometimes standards would benefit from including a non-normative section explaining a bit more of the reasoning behind specific design decisions.

Didn't catch on. ^C did, mapping to ascii equivalent just worked. "Hat" for control key was a winner.

That confused me a lot when I started using Linux as a teenager. There wasn’t really an explanation anywhere, some commands would just show ^Something and assume you’d know what to do. When I finally figured out, the terminal made a lot more sense.

Interesting how they didn't use hexadecimal the same way as we do today, instead writing e.g. the code position 0x7F as 7/15.

These didn't get much use as far as I know (and many computers of the 60s still used 6-bit characters and not anything resembling ASCII), but I think CP437 became the de-facto representation of the low characters for most of the 80s through at least the mid 90s.

https://upload.wikimedia.org/wikipedia/commons/f/f8/Codepage...

PCs weren't yet a dominant computing platform for most of the 80s.

If anyone is old enough to remember Joe Campbell's "C Programmer's Guide to Serial Communications", there was an excellent ASCII wall chart, which used these symbols for the control characters.

Apparently this later became ISO 2047 and most of these characters are mapped into Unicode (with the exception of a few which have reasonable substitutes).

I was wishing for something like this recently so I'm genuinely pleased to know this exists.

Which ones aren't? I think I've seen them all in during my work with adding legacy characters to Unicode 13 and now 16.

A bit of background on those control characters and what they mean:

https://en.wikipedia.org/wiki/C0_and_C1_control_codes

Character 7 is still a bell! I always loved that when you printed ASCII character 7 on old machines it made a sound instead of printing a character.

Old machines? Type "print(chr(7))" into the latest Python REPL and see what happens :)

  print("\a")

It's amazingly interesting to me that these exist and yet, do not seem to be commonly available in ascii fonts

I'm curious: Is there still a free copy available from ECMA in switzerland? I mean, besides this scanned one. I just love printed stuff.

Not sure if free, but they should be able to provide any current standard.

TIL. The burger icon (LF) was invented in 1968

Interesting. With a few exceptions (namely, BS/HT/LF/VT), these are identical on what the Amstrad CPC character set (https://archive.org/details/SOFT968TheAmstrad6128FirmwareMan...) looks like. Which was probably a copy from some other character set ROM.

Why have symbolic and alphabetic, I wonder

I think the idea was to be able to communicate them on devices that did not have the symbols (which turned out to be pretty much all of them)

Reply on news.ycombinator.com