[TUHS] Setting System V up for local echo TTYs?

Derek Peschel dpeschel at eskimo.com
Thu May 15 11:30:20 AEST 2008

A friend of mine has gotten an AT&T 3B2 running at the Vintage Telephone
Equipment Museum here in Seattle.  A Teletype model 33 and a 37 can now
also connect (through a small step-by-step switch and then a #5 crossbar)
to the computer.  Even if System V is not exactly classic UNIX, I hope
the configuration as a whole counts.

The 33 has local echo.  The 37 has it too (but supposedly that's easier
to change).  I've been experimenting with the correct stty settings, but
it's hard to get everything right.  Mostly I've been experimenting with
the 33 since the 37 just started working yesterday.

Could some setting cause line feeds to intermittently not happen, so that
two lines are overprinted?  I'm wondering if this is due to a mechanical
problem in the 33, or to line noise (which I know we are having) because
I can't see much pattern to when lines are being overprinted.

Are there any input settings that allow me to use LINE FEED and CAR RET
interchangeably as line terminators in canonical mode?  I'm assuming they
won't affect the output settings, so that programs can print NL (which
becomes CRLF) or CR (which stays CR).

Is the terminal driver smart enough to print the LF character while the
CR is happening, so I can shorten the delay settings?  That's only dealing
with output.  Is the driver smart enough to change the timing when dealing
with input? (since the driver can't change the LF key into CRLF because
the LF is already happening when the driver sees it).

I have tabs expanded on output.  Can I get the terminal driver to expand
them as input is being echoed?

And what controls echoing of login names? (besides /etc/gettydefs)  We
want to turn that off for certain lines.

If you need more details, they will have to wait until Tuesday.  Sorry.

And does anyone have any ideas about interesting ways to demonstrate the
features of the 37, 43, and 5610?  I thought eqn might be smart enough
to use the half and reverse line feeds, and vertical tabs, of our 37.
Does any software know about the ribbon colors?  What about software
to control tape readers and punches?  We probably don't have the extra
32 printing characters that dmr's pages on early UNIX mention.


-- Derek

More information about the TUHS mailing list