Apparently ECMA-6:1985 and ASCII-1986 declared UNIX line endings deprecated in favour of DOS/Windows-style ones and ECMA-48:1991 declared them disallowed... shows how well that worked.
(Source: https://www.aivosto.com/articles/control-characters.html#LF )
...and huh. So that's how horizontal and vertical tab characters were supposed to work in smart peripherals in a standardized way. The C1 extensions to ASCII for extended control characters say 0x88 is supposed to mean "set a horizontal tab stop at the current cursor position" and 0x8a is supposed to mean "set a vertical tab stop at the line the cursor is currently on."
There's also apparently 0x95, "Message Waiting" which, judging by the description, is supposed to be like BEL but setting an indicator that's persistent until dismissed.
