IBM 610, paper tape input, Selectric output.
In September, 1959, I was a sophomore at Notre Dame, taking EE 101,
the basic Electrical Engineering Circuits course with class three days
a week, and an associated Laboratory on Tuesdays. The first week's
Lab project had us measuring voltages and currents with many very old
and some new meters, each with a different ohms-per-volt
characteristic, comparing their accuracy, and we learned how to
prepare a formal report of an experiment. The second week's lab
experiment was to calculate the value of the Determinant of a
four-by-four matrix, primarily to show us the difference between
engineering and math. The corresponding math class we were all taking
would have the professor show us by Cramer's Rule how to calculate the
value of a linear system by dividing the determinant of matrix A by
the determinant of B to get the blackboard answer
X = [A] / [B] = 7
but this second week's lab project was to demonstrate that the actual
work of an engineer would be to calculate each of those determinants,
which involved a great deal of arithmetic and was not quite as simple
as the Math Prof's immediate answer.
As the EE Lab Professor (name now forgotten, but rather aged as I
recall) finished the instructions for that lab project, he said "I
have been instructed to read this note to all EE students", and
picking up a one-page, dittoed notice, he continued "The IBM
Corporation has donated a Model 610 digg-it-tal, er, digital,
computer, located in room 240, and students can sign up for blocks of
time to use it." Slamming the sheet of paper face down, he then said
"those digital things will never amount to anything, but next year, as
Juniors, you will be able to go across the hall to room 241 and use
the Bendix G15 Analog Computer - that's how we Electrical Engineer's
solve real problems!"
So I decided to investigate this IBM Digital Computer, and went to
room 240, which was on the left at the end of the hall that opened to
the very large lab with scores of motors and motor-generator that had
its large doors open to the warm September afternoon. I looked thru
the small window in the door and saw a 3 foot high, 5 foot wide gray
machine to the left of a table with a Selectric typewriter, and saw
someone who I assumed to be a junior/senior, leaning over the
typewriter. I opened the door to enter. As the door unhinged, so did
the student, shouting "Shut that G.D. door!" as he strode across the
room to the door, flailing his arms. As he stepped out into the hall
screaming "Didn't you read the damn sign?" he then saw that his
hand-written sign to "Get The Operators Permission Before Entering"
had fallen, face down on the floor. Calming, he informed me that you
must get the operator's attention, because the computer room was air
conditioned for the vacuum tubes and he needed to put the machine in
"QUIESCE/STOP" mode (which took 5-10 seconds), as only then was it
safe shuffle in, slowly, so as to not bring in warm air. The vacuum
tubes were so temperature sensitive, that air currents would cause
computation to fail, requiring a program restart.
He pointed me to the IBM manuals on the table beside the Selectric,
and I began to read, at page one. Several hours later, I had learned
how to punch the paper tape input (like the paper tape used in
Radioteletype at my ham radio station), and could print the tape on
the Selectric, and had used the IBM example to add 2 + 2 and print 4,
and I decided I would program the calculation of the determinant on
this new toy. I spent several hours each day, with no one else
entering the computer room, and by Saturday afternoon, I had punched
my program, had printed it, and was now ready to actually run my first
computer program. As I watched the nearly 30 feet of paper tape whir
thru the reader on the 610, its panel of nixie tubes flickered with
the address numbers. I recall crossing my arms and thinking "Wow, it
is 1959, I am a sophomore at Notre Dame, and I am running a real
program on a digital computer". The paper tape came to its end, the
printer came alive, and I received my first computer output; four
characters were printed, and the Selectric shut down:
WOW!
Of course, I didn't have the slightest idea of what was wrong, or how
to debug, so I remained in the computer room until after midnight
Saturday, then were back at 7am on Sunday, and finally, that senior,
(who, I'm very sorry to say, never gave his name, and I never saw him
again) happened by, and he examined the problem with me. He
discovered that I had kind of completely missed the difference between
"program" and "data", and that the first punch in the tape was a
control character that put the 610 in a scan mode to read the tape
until another control character was found, and that in the fifth from
end position it found a control character that changed the mode from
"scan" to "print" the characters on the tape, interpreting them as
machine instructions, and what had been printed out were the last four
computer instructions in my program:
W=Carriage Return,
O=Line Feed,
W= Carriage Return,
!=Print Accumulator!
(I had found the IBM recommendation to use two carriage returns to
ensure that the very slow print head on the Selectric was all the way
back to the left margin before printing a result!).
Fortunately, by late on Monday, I had actually figured out how to run
the program, and successfully computed the value of the 4x4
determinant, and on Tuesday (I think Sept 29, 1959) I submitted the
very first EE laboratory report at Notre Dame that used a digital
computer. While the report was accepted, (and correct), I saw nothing
by chagrin in that professor's face, and as I was never encouraged by
him or anyone else on the faculty, that was also my last use of a
computer while at Notre Dame.
Barry Merrill
Herbert W. "Barry" Merrill, PhD
President-Programmer
MXG Software
Merrill Consultants
10717 Cromwell Drive
Dallas, TX 75229
[email protected]
http://www.mxg.com - FAQ has Most Answers
[email protected] - invoices/PO/Payment
[email protected] - technical
tel: 214 351 1966 - expect slow reply, use email
fax: 214 350 3694 - prefer email, still works
-----Original Message-----
From: IBM Mainframe Discussion List [mailto:[email protected]] On Behalf
Of Shmuel Metz (Seymour J.)
Sent: Thursday, April 10, 2014 7:59 AM
To: [email protected]
Subject: Re: Another Golden Anniversary - Dartmouth BASIC
In <[email protected]>, on 04/09/2014
at 05:07 PM, Ed Finnell <[email protected]> said:
>Fortran II on SS80
Rara avis! I started on the IBM 650, which was much more common.
--
Shmuel (Seymour J.) Metz, SysProg and JOAT
ISO position; see <http://patriot.net/~shmuel/resume/brief.html>
We don't care. We don't have to care, we're Congress.
(S877: The Shut up and Eat Your spam act of 2003)
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