24 Mar
2016
24 Mar
'16
5:15 p.m.
That sounds like the Teletype model 33, and probably other Teletypes.
If you don't give it the extra .1 second of the LF, the first printed
character will overstrike in the middle of the line you just typed. And
it will be "bold" because the print head is moving very fast to the left.
Normally you'd want the LF to advance, but if you're trying to underline
by overstriking an underline character, you'd need to pad with a NUL.
The first model 33s I used didn't have an underline. That character was
a leftward pointing arrow, which I think was intended to visually show
backspace, and some systems (GE BASIC, IIRC) used it as an erase
character. (Of course, there was no ability to backspace on a 33.)
The caret printed as an upward pointing arrow, hence it's often called
"up arrow".
Mary Ann
On 03/24/2016 07:40 AM, George Ross wrote:
Make sure it
only prints 10 characters per second, then. (I think TTY's were
10 cps?) R-e-a-l-l-y s-l-o-w.
And don't forget that carriage-return takes
longer than printing individual
characters, so you need to send CR LF to give it time to get back to the
first column while it's feeding a line. Or CR CR LF just in case.
(Or was that the Olivetti terminal? Or the DECwriter? One of those
mechanical things anyway.)
--
George D M Ross MSc PhD CEng MBCS CITP, University of Edinburgh,
School of Informatics, 10 Crichton Street, Edinburgh, Scotland, EH8 9AB
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