4 Oct
2013
4 Oct
'13
10:31 a.m.
On Fri, Oct 4, 2013 at 1:13 PM, Mark J. Blair <nf6x at nf6x.net> wrote:
Thanks for sharing that here. I hadn't noticed
that post yet. I'm
in Riverside, so I've PM'd him to see if I can get one of the
terminals to go with the PDP-8 or PDP-11 that I hope to acquire
someday in the not too distant future.
The VT241 should have an 8-pin Mate-and-Lok 20mA connector
of the type we were discussing recently that was common with
TTYs. Most PDP-11s have EIA (RS-232) interfaces but the oldest
ones (11/20, 11/05...) also came equipped with 20mA current
loop interfaces. Older PDP-8s (up to and including the -8/e)
also did current loop, but from the -8/e onward, many had EIA.
The M8650 console interface does both - you just install the
right cable on it, and the jumper wire in the Berg connector
routes the correct line driver to the TTL input on the board.
I've never seen a TTY on a PDP-8/a but there's no reason
it couldn't be done. I thing it was just past the era of paper
tape and mechanical console teleprinters by then.
So the VT241 will work for any PDP-8 or PDP-11 you
eventually get. The other terminals are likely to be EIA
only and will work with most stuff made after about 1972
(but it is possible to buy/make a current loop adapter if
all you have is an EIA terminal).
-ethan