The mini-micro connection
Authors: Boynton G. R. 
Published: April 2007

The office of the future is defined. It is a work station
dominated by a micro computer which is in communication with more
powerful computers, large disks, printers, and other equipment
which can be shared. The large computers, disks, printers, and all
the rest already exist. Micro Computers or desk top computers
already exist. There are only two steps left in realizing the
office of the future. One step involves electronics; establishing
high speed communication between the desk top computer and all of
the other equipment. The second involves programming; defining and
developing coherent software systems. This paper is about the way
in which these two problems were handled by the department of
political science at the university of Iowa.

Weeg Computing Center provides academic computing services for
the University of Iowa. They do this with a collection of
computers; there is an I.B.M. 370, 5 Prime 750s, 4 Hewlett Packard
2000s, and a Vax. There are also disks, plotters, printers, and the
whole panoply of equipment one expects in a university computing
environment. In addition, a Gandalf communication system makes it
possible to access any one of these computers at speeds up to 2400
bits per second. These facilities are normally accessed with the
aid of one of the approximately 750 terminals on campus. With the
support of Weeg computing Center the department of political
science convinced the university administration that it would be
worthwhile experimenting with desk top computers for an entire
department. Money was made available, and 37 computers were
purchased. Which brought us to the two problems: high speed (in
this case 2400 bits per second) communication; and a coherent
system of programs.

Commodore 8032s were purchased, and this meant that we needed an
interface which would translate into the serial signal the Gandalf
system used. Several interfaces were available commercially, but we
could not make any of them work at 2400 bits per second. Nor could
we get the terminal emulator programs available commercially to
print the screen at 2400 bits per second. The dominant speed in
micro to larger computer communication is 300 b.p.s., fast means
1200 bits per second. An interface board was designed by the
electronics shop at the University for us, and a machine language
program was written which would handle sending and receiving at the
requisite speed. In principle this seemed a straightforward task.
In practice there was a stream of nitty gritty problems that seemed
as though it would go on forever. But it was done.

Three design considerations dominated the creation of the
software system. One, it had to be as simple to use as possible.
Half of the potential users had never used a computer before. That
implied that the system must be as automatic as possible. Two, it
had to, initially, provide a terminal to each user plus handle word
processing and electronic mail for the department. Three, it had to
allocate tasks between the desk top computers and the Weeg supplied
computers in a way that, within reasonable bounds, maximized the
work done on the desk top computers and minimized use of central
resources.

Two features of the system illustrate our attempt to make it as
easy to use as possible. First, signing on to the central computer
is almost automatic. Each person's copy of the machine language
program contains their four codes required to sign on to the
system. The individual can send these codes by pressing the control
key and the up arrow or programs developed for this system will
automatically send these codes. Signing off is equally automatic.
When the Prime on the other end has finished sending or receiving a
program or data it automatically signs off. Second, all choices are
made from two lists. One list is on the Prime, and the other list
is embedded in the software used on the CBM 8032. Physical
contiguity of choices reduces the amount of recall necessary to use
the system.

A good screen based text editing program enhances one's ability
to put words together. It does this by making it easy to write and
revise. However, there are many tasks, in addition to writing and
revising, that one needs to be able to carry out with the document
being written. You must be able to save and recall the text. It is
very nice to be able to append a second file to the one being
written. It is very nice to be able to save a segment of the file
being written. And the text must be sent to be printed. All of
these operations can be performed with the aid of the list of
commands in the text editing program. One presses 's' and gives a
file name; the programs do the rest. In addition, one would like to
be able to look at a list of files that have been created and
saved, delete files that are no longer needed, transfer a file to
the disk storage area of a collaborator for his or her review, send
a file (program or program control information) to the batch
processing system, and send a file directly from the disk to be
printed. All of these tasks can be performed using the list of
commands on the Prime. Most of the operations one can imagine
wanting to perform on a text file can be accomplished with one of
the two lists. That makes the system easy to learn; it provides
coherence.

In this system the Prime serves as the storage device and the
medium of communication. Programs and text files are stored on the
Prime disk; there are no disks for the desk top computers. In
addition, sending a file to be printed or sending a file to a
collaborator plus electronic mail are handled by the Prime. The
desk top computers handle the writing and revising which is done
with a program written in BASIC to run on these computers. Since
writing is an exceedingly important part of the job of academics
the computers are on all the time. But most of the time they are
not on to the central computing resources; they are working as
stand alone computers.

When you walk up and down the hall in the department of
political science you see lots of computers going. Writing has
become much easier. And getting a final document produced has never
been as easy or as fast. The mini-micro connection works.