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At 12:11 PM 5/5/98 -0400, you wrote:
>At 11:58 AM 5/5/98 -0400, Aron Insinga wrote:
>>Some of you remember the laser printer that Pete and his students built
>>from a Xerox telecopier that virtually stopped time-sharing on EE's 11/70
>>so that it could become a device controller whenever anybody printed
>>something. (It wasn't completed until after my time.)
>Is *THAT* what it was? I had no idea it was a homebrew. By 1979 it was
>working. DELTA's only access to it was batch-style; we would "print" the
>jobs out to a magtape, which the UDCC operators would then take over to
>whatever machine controlled the XEROX printer and run it out overnight. My
>"unofficial history" records that Bob Mader wrote the first version of the
>Xerox program and Rich Thomson wrote the second.
I think these are 2 different things. The homebrew printer was Pete's pet
project. When he was at Xerox, they started to build this laser printer,
but turned it into The Xerox Telecopier (Telecopier = Fax Machine) because
they didn't think there was a market for it or the XGP [XeroGraphic
Printer; there were a few at places like CMU and MIT] was good enough or
something. When he became chairman of the EE Dept. at UofD, he brought a
couple of them with him, to prove that it really was a good idea to build
it as a printer. He gutted the electronics and used the mechanical part as
the basis for a laser printer. There was a huge (2'x3'?) plexiglass board
full of ECL SRAM chips for the buffer. (Probably 256 bits -- not kbits --
per chip.) It was in the EE Dept.
The Xerox printer at the computer center was a Xerox 1200. It had a
magtape drive on it. It did not take PostScript or HP-whatever
specification of where the pixels go like a laser printer does today.
Instead, it took characters off of the tape and (like a phototypesetter) it
moved an optical mask to position the character to print in front of a
strobe light, and flashed the strobe light, and the light exposed the right
places on the printer's xerographic drum to make the character. These were
fully-formed characters like a typewriter, not assemblages of pixels like a
dot-matrix printer. The place where everybody saw its output was in the
library: every day, a new list of the checked out books was printed and
available on the counter. (The library wasn't on-line; when books were
checked in or out, an entry as made on a magtape, which the computer center
used to update the list of checked out books and generate a new report. It
didn't take as much computer power as the current on-line system that knows
about all of the books.) I thought that Dan wrote the program to generate
tapes for it. One of my book marks still in an old computer book is a
print job card for this printer with Dan's writing on it. I probably used
it to print the UNIX sources, which were eventually scrambled by a mover
who helpfully shuffled the paper into a new box.
Anyway, another application at Delta: The library or library science
department was doing a PERT simulation of how to migrate from the off-line
system to the on-line system by entering books into the on-line catalog the
books as they were checked in. I don't know what the PERT program they had
was written in (probably FORTRAN), but I translated it to BASIC so they
could do their simulations, and became a reference in their paper. So
developing these applications, we not only learned more about computers, we
learned about things in the real-world that people computers happened to
use computers for.
>>As for ugly fonts, I think that the 11/50's 132-column Centronics dot
>>matrix printer shook the butcher-block lab table when it did a carriage
>>return, and the table had to be moved so that it wouldn't bang into the
>I believe that printer survived into 358, but not into Willard Hall.
358 was originally a computer center terminal room with a handful of TTYs
and dataphones. It was used by the EE program for high school students.
Of course it got used a lot to call next door to Delta's system. I think
someone even dragged a TTY (maybe the one on wheels that Teresa used at
home and on demos) to the first floor in the hall where there was a pay
phone... There was another one nearby in the basement of Colburn Lab.
Once when I was in 358 when it was a TTY room, I took a couple of calls
from some telemarketer dialing phone number+1, +1, +1... "This phone is
connected to a computer terminal that doesn't want to subscribe to any
magazines." ... "This phone is also connected to a computer terminal and I
don't think that it wants to subscribe to any magazines either." "How many
more are there?" "A few dozen." So I guess that I saved a couple of dozen
people from a telemarketing call.