[TUHS] Teletype simulator?

Mary Ann Horton mah at mhorton.net
Fri Mar 25 02:15:49 AEST 2016

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
> Mail: gdmr at inf.ed.ac.uk   Voice: 0131 650 5147   Fax: 0131 650 6899
> PGP: 1024D/AD758CC5  B91E D430 1E0D 5883 EF6A  426C B676 5C2B AD75 8CC5
> The University of Edinburgh is a charitable body, registered in
> Scotland, with registration number SC005336.

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