[ih] Larry Roberts & RD the first electronic mail manager software [was written in TECO on TENEX]

[Brian E Carpenter]

Jack,

> Imlacs had no I/O except RS232.

That's not quite true, but you needed a tame electronics engineer.
I specified, and someone else designed, a 16-bit parallel communications
interface for the Imlac PDS-1 in 1971. Like the PDP-8 and PDP-11, the
Imlac had provision for connecting homebrew perhipherals. (The Imlac
designers came from Digital.)

Unfortunately I don't have any documentation of that hardware, but the
associated software is documented at
https://github.com/larsbrinkhoff/imlac-software/tree/master/CERN-PDS1
It certainly wasn't teleconferencing.

Regards
    Brian Carpenter

On 09-Aug-23 07:55, Jack Haverty via Internet-history wrote:
> Just a few years ago, I stumbled across an Annual Report that MIT
> submitted for one year's work in the early 70s.  Since I was there at
> the time, I was curious how history recorded what we were doing then.
> Looking at the section for our group, I found a description of a
> revolutionary implementation of a teleconferencing system that allowed
> people to interact in real time using the ARPANET which had been
> completed that year.
> 
> I didn't remember that we had built any teleconferencing system. Of
> course with age comes memory loss.  But I remember lots of stuff we did
> then, but not a "teleconferencing system".   A sign of encroaching
> dementia...?
> 
> With further investigation...
> 
> A bunch of us at MIT in Licklider's group spent a lot of hours getting
> multi-player MazeWar running on our fancy new Imlac minicomputers.
> Someone added a feature where players could trash-talk each other with a
> shared screen space trying to lure them into an ambush or gloat on
> another kill.   MazeWars of course had nothing to do with whatever
> research we were doing.   Gettings MazeWar going was just a lot of fun.
> We all thought MazeWars was just a cool hack and extremely addictive
> game.   If curious, see
> https://www.digibarn.com/collections/games/xerox-maze-war/index.html
> 
> But the experience did reveal, to me at least, the importance of
> latency, and the difficulties of getting a bunch of computers to
> interact over a network.   Imlacs had no I/O except RS232.  So, our
> "LAN" was a star-shaped configuration with Imlac minicomputers connected
> via RS232 to our PDP-10 as the center of the star (7 floors away), and I
> had goosed the RS232 hardware well beyond its spec to achieve almost 100
> kb/sec.  I tried to convince BBN to upgrade the TIP hardware to support
> higher speed "terminals", but was rebuffed -- "The TIP supports
> terminals up to the maximum reasonable speed of 9600 bits/second."
> 
> MIT's Annual Report touted Maze as a "teleconferencing system".
> 
> Jack
> 
>