[TUHS] terminal - just for fun

Milo Velimirović milov at cs.uwlax.edu
Thu Aug 7 02:49:42 AEST 2014


I used v6 on an 11/45 -- my comments refer to my recollections from the mid-late 1970s.

On Aug 6, 2014, at 10:26 AM, Jeremy C. Reed <reed at reedmedia.net> wrote:

> On Wed, 6 Aug 2014, John Cowan wrote:
> 
>>> So the model-33 wasn't ASCII?
>> 
>> The keyboard could send all of ASCII except lower-case letters, grave,
>> braces, and vertical bar (i.e. excluding x60 to x7E).  The high-order
>> bit was always set.  Using the paper tape reader and punch, you could
>> transmit arbitrary 8-bit characters.
> 
> I guess it was common to use the Teletype Model 33 independently without 
> any video display. (I read that it could accommodate a modem too.) Did 
> it automatically print to paper everything typed to keyboard in 
> real-time?  Or maybe only when LINE FEED or RE-TURN key was pressed?

What video? I don't recall ever seeing a TTY have video displays.
Terminals could operate in either Full Duplex or Half Duplex. The former required every character to be echoed in order to be printed. In HDX mode every character typed was both sent down the wire and printed.

Yes, some TTYs had an attached acoustic coupler and/or a paper tape reader-punch.

> 
> How would RUB OUT be used when using the sh shell? (I tried looking 
> through the code and manual for some old 32V and previous versions but 
> didn't see code for it yet.)

It wasn't really used. Most often rubout was used on systems where a "text" would be prepared offline and punched on paper tape as it was being typed. Hitting rubout would punch holes in all positions on the tape effectively obliterating  whatever had been typed. Once the offline text was complete the tape could be transmitted to a host for further processing. This was the Automatic Send part of the ASR-33. I recall doing this in the early 70s at a community college I went to -- but this wasn't connected to a UNIX system.

> 
> When did the sh shell provide intra-line editing?
From the beginning if you count @ and #
> 
> Were the early Unix versions case insensitive? (Like could I run "DaTe" 
> from shell?) If not, how to get the model-33 to work with it?

How early are asking about. V6 was case sensitive. The ASR-33 was folded to lower case on input by default.

> 
> What about the model-33 printer? Did it print lowercase?

Upper case only as previous posters have mentioned.

> 
> How was the "HERE IS" key programmed? Was it used in Unix?

No idea; I never saw it used.

> 
> What was the "REPT" key used for?
ditto.
> 
> I also noticed there wasn't any tilde key. So I looked at some old Unix 
> code and didn't see tilde used for home directory until 1980 csh. But 
> how was tilde entered for previous uses? (Maybe I just overlooked on 
> keyboard.)
probably as \- I'd have to look at the terminal driver code.
> 
> Was there any concept of intra-line editing when using a model-33 -- but 
> without seeing what is being typed or having it print over (and over) 
> same line content? (I should assume that intra-line editing can only 
> happen on video terminals.)

Not really. You had @ and # and that was about it. You could always manually advance the paper in the TTY if things got to smudged up from overprinting.

> 
> (My book in progress explains a lot about the history of ex/vi but 
> the earliest version I have is 1.1 which included the support for 
> intra-line editing and even visual mode for HP 2645 and LSI ADM-3A 
> cursor-addressible terminals. I am hoping my book can also introduce the 
> basic usage concepts for readers who have no familiarity with the 
> hardware around then. One of the TUHS list participants and termcap/vi 
> developer already told me some about the hjkl arrow keys, for example.)

--
Milo Velimirović
Network Specialist - ITS Network Services
608.785.6618 Office -  608.386.2817 Cell
University of Wisconsin - La Crosse
La Crosse, Wisconsin 54601 USA   43 48 48 N 91 13 53 W








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