Tom's Datatron 205

Burroughs 205 HomePage

(the material on this page and other linked Datatron 205 pages are excerpted from Tom's forthcoming computer history book) 


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I'll always remember the first time that I encountered the Burroughs 205.  I was a freshman at the University of Portland in the fall of 1963.  Father Duffy was my Calculus teacher and during a class that autumn, he mentioned that the University was looking for someone to help out in the computer center.  Was anyone interested?  Uncharacteristically for me in those days, I quickly raised my hand.                

University of Portland computer center director, Peter C. Knobloch explains some of the finer points of programming
 to two of his engineering students

A couple of days later I approached the computer room door.  Two classrooms on the first floor of the Engineering Building had been converted into a computer center earlier that year.  General Insurance Company of America, based in Seattle, had donated to the University a surplus B205 system that pretty well filled about eighty percent of the space.  A bit of office space took up the balance of the area.

As I walked through the door into the actual computer room, I was greeted by the combination of electronic hum and rush of air conditioning that was typical of early mainframe computers.

Burroughs recommended an area of about twenty by forty feet for a computer room.  This gave plenty of space to spread out the several refrigerator-sized cabinets that made up a computer in the 1960s.

 The U of P computer room was pretty typical of mainframe installations at the time.  The computer stood atop a four-inch thick raised floor.  The floor served two purposes.  First, it provided room to run the thick cables that interconnected the computer and its peripheral devices such as the IBM 407 accounting machine that served as a printer.  Second, it served to allow the movement of cool air from the air-conditioning system into the bottoms of all the cabinets that were filled with heat-producing vacuum tubes.


The Datatron was already obsolete.  With a 1954 introduction date, this was a nine year old design, and that was the reason that General Insurance was happy to part with it.  But the computer still had plenty of life in it for educational and some administrative purposes.  

For the University of Portland to have its own computer on campus was quite a mark of distinction.  We were a Catholic liberal arts university with slightly over two thousand students.  Our downtown state college rival, Portland State College, couldn't boast of its own computer for educational purposes although it had a great programming instructor, Dr. Robert Broussard, who utilized another Datatron.  Miles to the south, the distinguished engineering school of Oregon State University could only point to its ALWAC III-e, a machine of comparable age, power and design.

The Datatron, From Consolidated Engineering to Burroughs

The Datatron has a fascinating background as it evolved from a "skunk works" project in the back room of an electronics instrument company in southern California to become the backbone of the Burroughs Corporation's tardy move into computers.

Consolidated Engineering Corporation (CEC) was a well established manufacturer of test instruments in the 1950s.  Founded by Herbert Hoover, Jr., son of the former U.S. president, CEC developed test instrumentation for the petroleum industry.  CEC was located in Pasadena and had a close working relationship with Cal Tech which included the presence of two Cal Tech faculty on the CEC board of directors.  CEC developed a very successful line of Mass Spectrometers.  Clifford Berry, as Chief Physicist at CEC  held a number of patents in the Spectrometer field.  Years earlier, Berry had been half of the Atanasoff-Berry team that developed the first rudimentary digital computer at Iowa State.  (This machine was demonstrated to John Mauchly of ENIAC fame in 1941 and therein lies another chapter or two in everyone's modern day version of computer history.)


The major output of the Mass Spectrometer was data and lots of it.  To produce the needed analysis, one had to solve a set of simultaneous linear equations.  This required a lot of manual work with the calculators of the day.  Cliff Berry and Sibyl Rock developed and patented an analog computer that produced excellent results solving a series of 12 simultaneous equations in 12 unknowns.  This was now 1946 and this analog computer further cemented CEC's position in the Spectrometer business.  As more years passed, Berry realized the potential for the digital computer to further enhance CEC's edge in his part of the business.  He pressed CEC to develop their own digital computer.  In 1951, CEC engaged Harry Huskey, then working on the National Bureau of Standards SWAC computer at nearby UCLA as a lecturer on digital technology to the project team.

Progress was relatively slow at first.  CEC needed someone who could bridge the gap between Huskey and the design team. Another mathematician, this one an expert in number theory, the Norwegian Ernst Selmer, was lecturing at Cal Tech.  Selmer had come to the United States to learn about electronic computing technology on an eighteen-month visit.  He arrived in January of 1951 bound for Princeton where the IAS computer was being constructed for John Von Neumann.  Selmer relates an amusing anecdote in this video as he describes his initial visit to the Institute.  From Princeton, Selmer traveled to Berkeley where he contributed to the CALDIC computer being constructed by Paul Morton.  He was hired by CEC management as a consultant late in 1951 and ultimately designed most of the logic for the Datatron. 

By May  of 1952, Chief Engineer, L. P. Robinson, was able to describe the Datatron (then known as the CEC 30-201) as part of a Navy symposium at the Pentagon on "Commercially Available General-Purpose Electronic Digital Computers of Moderate Price."  To describe the Datatron as "commercially available" at this point was a bit of a stretch.  It would be a full year until the first "breadboard" version of the machine was complete and over two years until the first production unit shipped.

The Datatron Breadboard as it appeared in the CEC 1952 Annual Report

While the technical team went about engineering the computer, CEC management had other worries.  They understood that the computer business was far different from the instrument business that they were in.  In 1952, they designated the development group as a separate Computer Division and during the summer of that year the team of about thirty people moved into a vacant market building at 717 North Lake Avenue in Pasadena.  

Realizing that the continued development of the CEC computer was going to take a great deal of money, CEC management decided to spin off the Computer Division as a separate corporation but retained a thirty-six percent ownership in the new company, ElectroData Corporation.   ElectroData went public on the American Stock Exchange at $3.50 a share in April of 1954.  It would rise as high as $21 in spite of a lack of profits.

Formal announcement of the ElectroData 203 computer took place in February of 1954.  In April of 1954, the New York Times noted the introduction of a new "electronic brain" by ElectroData at the bargain rate of about $125,000.  During 1954 ElectroData was running ads in Fortune promoting their Electronic Data-Processing Equipment for Science, Industry and Commerce.  In June of 1954, the first production model shipped to the nearby Jet Propulsion Laboratory at Cal Tech.  A total of seven systems were shipped in 1954 followed by thirteen more in 1955.  The production line was humming.

ElectroData Production Line in 1955

Since competitive pressures required that computer be available via lease, costs continued to mount, however, and revenue was comparatively slim.  The new corporation had outgrown their first home and moved to a larger facility at 460 Sierra Madre Villa, still in Pasadena.  In early 1956, Phillip Fogg, Chairman of CEC set up a board meeting to consider the future of his ElectroData computer operation.  ElectroData had now become the third largest manufacturer of computers in the world!  Fogg and the board realized that while they had an excellent product, continued development, sales expense and rapid growth were going to require about $60 million over the next five years.  This was twice the net worth of CEC.  CEC/ElectroData was on the verge of throwing in the towel.

As fate would have it, that very day a phone call came in from John Coleman, the president of Burroughs Corporation.  Now, Burroughs was a significant manufacturer of office computation equipment.  That meant primarily mechanical adding machines and banking equipment at the time.  Anyone who ever had to move one of these beasts from one table to another knows that if they were priced by the pound, Burroughs was probably doing all right financially.  Realizing that office calculation was going electronic, their first venture into the marketplace was a timid one with a specialized machine lacking a stored program architecture, the E101, rather than a General Purpose computer.  They found their customers saying, "No thanks, we are going with a full General Purpose computer."

As Burroughs management looked around for a way to jump start their entry into the computer field, they spotted ElectroData.  On July 1, 1956 Burroughs purchased ElectroData Corporation from CEC in a stock swap with one share of Burroughs at $34 a share for each two shares of ElectroData.

Regardless of whether you see reference to the Datatron as a CEC 30-201,  CEC 30-203, an ElectroData 204 or 205, or a Burroughs 205, it is all the same machine.  The numbers primarily signify the development and addition of new peripherals.  The CEC 30-201 described at the Pentagon had only paper tape input and Flexowriter output.  That machine had the same architecture, clock cycle and performance as the later Burroughs 205.  While the 201 only had 34 instructions, most of what was added later were instructions to handle the Tape, Cardatron and Floating Point units.

What Made the Datatron Special?

It seems that almost everyone who encountered the Burroughs 205 and continued their involvement with computers developed a real affection for the machine.  There are reasons for this, of course.

What Made a Datatron Installation Successful?

Success or failure of an individual Datatron site depended largely on the capability of the maintenance staff.  Known as "Field Engineers" based on CEC's earlier designation, these intrepid folks had to master and in some cases invent techniques for minimizing the frequency and duration of machine outages.  On a separate page I have described some of these techniques as practiced by one of the best. 

Continue to B205 Development Chronology


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