'eniac' Episodes

Happy Birthday ENIAC

     2/15/2020

Today we’re going to celebrate the birthday of the first real multi-purpose computer: the gargantuan ENIAC which would have turned 74 years old today, on February 15th. Many generations ago in computing. The year is 1946. World War II raged from 1939 to 1945. We’d cracked Enigma with computers and scientists were thinking of more and more ways to use them. The press is now running articles about a “giant brain” built in Philadelphia. The Electronic Numerical Integrator and Computer was a mouthful, so they called it ENIAC. It was the first true electronic computer. Before that there were electromechanical monstrosities. Those had to physically move a part in order to process a mathematical formula. That took time. ENIAC used vacuum tubes instead. A lot of them. To put things in perspective: very hour of processing by the ENiAC was worth 2,400 hours of work calculating formulas by hand. And it’s not like you can do 2,400 hours in parallel between people or in a row of course. So it made the previous almost impossible, possible. Sure, you could figure out the settings to fire a bomb where you wanted two bombs to go in a minute rather than about a full day of running calculations. But math itself, for the purposes of math, was about to get really, really cool. The Bush Differential Analyzer, a later mechanical computer, had been built in the basement of the building that is now the ENIAC museum. The University of Pennsylvania ran a class on wartime electronics, based on their experience with the Differential Analyzer. John Mauchly and J. Presper Eckert met in 1941 while taking that class, a topic that had included lots of shiny new or newish things like radar and cryptanalysis. That class was mostly on ballistics, a core focus at the Moore School of Electrical Engineering at the University of Pennsylvania. More accurate ballistics would be a huge contribution to the war effort. But Echert and Mauchly wanted to go further, building a multi-purpose computer that could analyze weather and calculate ballistics. Mauchly got all fired up and wrote a memo about building a general purpose computer. But the University shot it down. And so ENIAC began life as Project PX when Herman Goldstine acted as the main sponsor after seeing their proposal and digging it back up. Mauchly would team up with Eckert to design the computer and the effort was overseen and orchestrated by Major General Gladeon Barnes of the US Army Ordnance Corps. Thomas Sharpless was the master programmer. Arthur Burkes built the multiplier. Robert Shaw designed the function tables. Harry Huskey designed the reader and the printer. Jeffrey Chu built the dividers. And Jack Davis built the accumulators. Ultimately it was just a really big calculator and not a computer that ran stored programs in the same way we do today. Although ENIAC did get an early version of stored programming that used a function table for read only memory. The project was supposed to cost $61,700. The University of Pennsylvania Department of Computer and Information Science in Philadelphia actually spent half a million dollars worth of metal, tubes and wires. And of course the scientists weren’t free. That’s around $6 and a half million worth of cash today. And of course it was paid for by the US Army. Specifically the Ballistic Research Laboratory. It was designed to calculate firing tables to make blowing things up a little more accurate. Herman Goldstine chose a team of programmers that included Betty Jennings, Betty Snyder, Kay McNulty, Fran Bilas, Marlyn Meltzer, and Ruth Lichterman. They were chosen from a pool of 200 and set about writing the necessary formulas for the machine to process the requirements provided from people using time on the machine. In fact, Kay McNulty invented the concept of subroutines while working on the project. They would flip switches and plug in cables as a means of programming the computer. And programming took weeks of figuring up complex calculations on paper. . Then it took days of fiddling with cables, switches, tubes, and panels to input the program. Debugging was done step by step, similar to how we use break points today. They would feed ENIAC input using IBM punch cards and readers. The output was punch cards as well and these punch cards acted as persistent storage. The machine then used standard octal radio tubes. 18000 tubes and they ran at a lower voltage than they could in order to minimize them blowing out and creating heat. Each digit used in calculations took 36 of those vacuum tubes and 20 accumulators that could run 5,000 operations per second. The accumulators used two of those tubes to form a flip-flop and they got them from the Kentucky Electrical Lamp Company. Given the number that blew every day they must have loved life until engineers got it to only blowing a tube every couple of days. ENIAC was modular computer and used different panels to perform different tasks, or functions. It used ring counters with 10 positions for a lot of operations making it a digital computer as opposed to the modern binary computational devices we have today. The pulses between the rings were used to count. Suddenly computers were big money. A lot of research had happened in a short amount of time. Some had been government funded and some had been part of corporations and it became impossible to untangle the two. This was pretty common with technical advances during World War II and the early Cold War years. John Atanasoff and Cliff Berry had ushered in the era of the digital computer in 1939 but hadn’t finished. Maunchly had seen that in 1941. It was used to run a number of calculations for the Manhattan Project, allowing us to blow more things up than ever. That project took over a million punch cards and took precedent over artillery tables. Jon Von Neumann worked with a number of mathematicians and physicists including Stanislaw Ulam who developed the Monte Method. That led to a massive reduction in programming time. Suddenly programming became more about I/O than anything else. To promote the emerging computing industry, the Pentagon had the Moore School of Electrical Engineering at The University of Pennsylvania launch a series of lectures to further computing at large. These were called the Theory and Techniques for Design of Electronic Digital Computers, or just the Moore School Lectures for short. The lectures focused on the various types of circuits and the findings from Eckert and Mauchly on building and architecting computers. Goldstein would talk at length about math and other developers would give talks, looking forward to the development of the EDVAC and back at how they got where they were with ENIAC. As the University began to realize the potential business impact and monetization, they decided to bring a focus to University owned patents. That drove the original designers out of the University of Pennsylvania and they started the Eckert-Mauchly Computer Corporation in 1946. Eckert-Mauchley would the build EDVAC, taking use of progress the industry had made since the ENIAC construction had begun. EDVAC would effectively represent the wholesale move away from digital and into binary computing and while it weighed tons - it would become the precursor to the microchip. After the ENIAC was finished Mauchly filed for a patent in 1947. While a patent was granted, you could still count on your fingers the number of machines that were built at about the same time, including the Atanasoff Berry Computer, Colossus, the Harvard Mark I and the Z3. So luckily the patent was avoided and digital computers are a part of the public domain. That patent was voided in 1973. By then, the Eckert-Mauchly computer corporation had been acquired by Remington Rand, which merged with Sperry and is now called Unisys. The next wave of computers would be mainframes built by GE, Honeywell, IBM, and another of other vendors and so the era of batch processing mainframes began. The EDVAC begat the UNIVAC and Grace Hopper being brought in to write an assembler for that. Computers would become the big mathematical number crunchers and slowly spread into being data processors from there. Following decades of batch processing mainframes we would get minicomputers and interactivity, then time sharing, and then the PC revolution. Distinct eras in computing. Today, computers do far more than just the types of math the ENIAC did. In fact, the functionality of ENIAC was duplicated onto a 20 megahertz microchip in 1996. You know, ‘cause the University of Pennsylvania wanted to do something to celebrate the 50th birthday. And a birthday party seemed underwhelming at the time. And so the date of release for this episode is February 15th, now ENIAC Day in Philadelphia, dedicated as a way to thank the university, creators, and programmers. And we should all reiterate their thanks. They helped put computers front and center into the thoughts of the next generation of physicists, mathematicians, and engineers, who built the mainframe era. And I should thank you - for listening to this episode. I’m pretty lucky to have ya’. Have a great day! .


Road to Transistors: Part I

     5/31/2020

The transistor changed the world. It made small, complex, and cheap computing possible. But it wasn't the first attempt to crack the case. There is a long and strange lineage of similar devices leading up to the transistor. In this episode we take a look at two of those devices. First the vacuum tube, one of the first components that made computing possible. Then the cryotron, the first device purpose built for computers.

You can find the full audio of Atanasoff's talk here: https://www.youtube.com/watch?v=Yxrcp1QSPvw

Like the show? Then why not head over and support me on Patreon. Perks include early access to future episodes, and stickers: https://www.patreon.com/adventofcomputing

Important dates in this episode:

1880: Thomas Edison Rediscovers Thermionic Emission
1904: Ambrose Fleming Invents the Vacuum Tube
1906: Lee de Forest Patents the Audion Triode Tube
1937: George Stibitz Creates First Binary Adding Circuit from Spare Relays
1938: John Atanasoff Visits a 'Honkey-Tonk'
1941: ABC, First Vacuum Tube Calculator, is Completed
1953: Cryotron Invented by Dudley Allen Buck


ENIAC, Part I

     11/16/2020

Completed in 1945, ENIAC was one of the first electronic digital computers. The machine was archaic, but highly influential. But it wasn't a totally new take on computing. Today we are taking a look at the slow birth of ENIAC, how analog computers started to fall apart, and how earlier ideas transitioned into the digital future.

Like the show? Then why not head over and support me on Patreon. Perks include early access to future episodes, and bonus content: https://www.patreon.com/adventofcomputing


ENIAC, Part II

     11/30/2020

In 1946 John Eckert and John Mauchly left the Moore School, patented ENIAC, and founded a company. One of those discussions would have consequences that wouldn't be resolved until 1973. Today we close out our series on ENIAC with a look at the legal battle it spawned, and how it put ownership over the rights to basic digital technology on trial. Along the way we talk legal gobbledygook, conspiracy, and take a look at some of the earliest electronic computers.

Like the show? Then why not head over and support me on Patreon. Perks include early access to future episodes, and bonus content: https://www.patreon.com/adventofcomputing


Mercury Memories

     6/13/2021

This episode we take a look at the earliest days of computing, and one of the earliest forms of computer memory. Mercury delay lines, originally developed in the early 40s for use in radar, are perhaps one of the strangest technologies I've even encountered. Made primarily from liquid mercury and quartz crystals these devices store digital data as a recirculating acoustic wave. They can only be sequentially accessed. Operations are temperature dependent. And, well, the can also be dangerous to human health. So how did mercury find it's way into some of the first computers?

Like the show? Then why not head over and support me on Patreon. Perks include early access to future episodes, and bonus content: https://www.patreon.com/adventofcomputing


The Von Neumann Architecture

     11/12/2021

John Von Neumann was born in Hungary at the tail end of the Astro-Hungarian Empire. The family was made a part of the nobility and as a young prodigy in Budapest, He learned languages and by 8 years old was doing calculus. By 17 he was writing papers on polynomials. He wrote his dissertation in 1925 he added to set theory with the axiom of foundation and the notion of class, or properties shared by members of a set. He worked on the minimax theorem in 1928, the proof of which established zero-sum games and started another discipline within math, game theory. By 1929 he published the axiom system that led to Von Neumann–Bernays–Gödel set theory.

And by 1932 he’d developed foundational work on ergodic theory which would evolve into a branch of math that looks at the states of dynamical systems, where functions can describe a points time dependence in space. And so he of course penned a book on quantum mechanics the same year.

Did we mention he was smart and given the way his brain worked it made sense that he would eventually gravitate into computing. He went to the best schools with other brilliant scholars who would go on to be called the Martians. They were all researching new areas that required more and more computing - then still done by hand or a combination of hand and mechanical calculators.

The Martians included De Hevesy, who won a Nobel prize for Chemistry. Von Kármán got the National Medal of Science and a Franklin Award. Polanyl developed the theory of knowledge and the philosophy of science. Paul Erdős was a brilliant mathematician who published over 1,500 articles. Edward Teller is known as the father of the hydrogen bomb, working on nuclear energy throughout his life and lobbying for the Strategic Defense Initiative, or Star Wars.

Dennis Gabor wrote Inventing the Future and won a Nobel Prize in Physics. Eugene Wigner also took home a Nobel Prize in Physics and a National Medal of Science. Leo Szilard took home an Albert Einstein award for his work on nuclear chain reactions and joined in the Manhattan Project as a patent holder for a nuclear reactor. Physicists and brilliant scientists. And here’s a key component to the explosion in science following World War II: many of them fled to the United States and other western powers because they were Jewish, to get away from the Nazis, or to avoid communists controlling science.

And then there was Harsanyl, Halmos, Goldmark, Franz Alexander, Orowan, and John Kemeny who gave us BASIC. They all contributed to the world we live in today - but von Neumann sometimes hid how smart he was, preferring to not show just how much arithmetic computed through his head.

He was married twice and loved fast cars, fine food, bad jokes, and was an engaging and enigmatic figure. He studied measure theory and broke dimension theory into algebraic operators. He studied topological groups, operator algebra, spectral theory, functional analysis and abstract Hilbert space. Geometry and Lattice theory. As with other great thinkers, some of his work has stood the test of time and some has had gaps filled with other theories. And then came the Manhattan project. Here, he helped develop explosive lenses - a key component to the nuclear bomb.

Along the way he worked on economics and fluid mechanics. And of course, he theorized and worked out the engineering principals for really big explosions. He was a commissioner of the Atomic Energy Commission and at the height of the Cold War after working out game theory, developed the concept of mutually assured destruction - giving the world hydrogen bombs and ICBMs and reducing the missile gap. Hard to imagine but at the times the Soviets actually had a technical lead over the US, which was proven true when they launched Sputnik. As with the other Martians, he fought Communism and Fasciscm until his death - which won him a Medal of Freedom from then president Eisenhower.

His friend Stanislaw Ulam developed the modern Markov Chain Monte Carlo method and Von Neumann got involved in computing to work out those calculations. This combined with where his research lay landed him as an early power user of ENIAC. He actually heard about the machine at a station while waiting for a train. He’d just gotten home from England and while we will never know if he knew of the work Turing was doing on Colossus at Bletchley Park, we do know that he offered Turing a job at the Institute for Advanced Study that he was running in Princeton before World War II and had read Turing’s papers, including “On Computable Numbers” and understood the basic concepts of stored programs - and breaking down the logic into zeros and ones.

He discussed using ENIAC to compute over 333 calculations per second. He could do a lot in his head, but he wasn’t that good of a computer. His input was taken and when Eckert and Mauchly went from ENIAC to EDVAC, or the Electronic Discrete Variable Calculator, the findings were published in a paper called “First Draft of a Report on the EDVAC” - a foundational paper in computing for a number of reasons.

One is that Mauchly and Eckert had an entrepreneurial spirit and felt that not only should their names have been on the paper but that it was probably premature and so they quickly filed a patent in 1945, even though some of what they told him that went into the paper helped to invalidate the patent later. They considered these trade secrets and didn’t share in von Neumann’s idea that information must be set free.

In the paper lies an important contribution, Von Neumann broke down the parts of a modern computer. He set the information for how these would work free. He broke down the logical blocks of how a computer works into the modern era. How once we strip away the electromechanical computers that a fully digital machine works. Inputs go into a Central Processing Unit, which has an instruction register, a clock to keep operations and data flow in sync, and a counter - it does the math. It then uses quick-access memory, which we’d call Random Access Memory, or RAM today, to make processing data instructions faster. And it would use long-term memory for operations that didn’t need to be as highly available to the CPU. This should sound like a pretty familiar way to architect devices at this point.

The result would be sent to an output device. Think of a modern Swift app for an iPhone - the whole of what the computer did could be moved into a single wafer once humanity worked out how first transistors and then multiple transistors on a single chip worked.

Yet another outcome of the paper was to inspire Turing and others to work on computers after the war. Turing named his ACE or Automatic Computing Engine out of respect to Charles Babbage. That led to the addition of storage to computers. After all, punched tape was used for Colossus during the war and and punched cards and tape had been around for awhile. It’s ironic that we think of memory as ephemeral data storage and storage as more long-term storage. But that’s likely more to do with the order these scientific papers came out than anything - and homage to the impact each had.

He’d write The Computer and the Brain, Mathematical Foundations of Quantum Mechanics, The Theory of Games and Economic Behavior, Continuous Geometry, and other books. He also studied DNA and cognition and weather systems, inferring we could predict the results of climate change and possibly even turn back global warming - which by 1950 when he was working on it was already acknowledged by scientists. As with many of the early researchers in nuclear physics, he died of cancer - invoking Pascal’s wager on his deathbed. He died in 1957 - just a few years too early to get a Nobel Prize in one of any number of fields.

One of my favorite aspects of Von Neumann was that he was a lifelong lover of history. He was a hacker - bouncing around between subjects. And he believed in human freedom. So much so that this wealthy and charismatic pseudo-aristocrat would dedicate his life to the study of knowledge and public service. So thank you for the Von Neumann Architecture and breaking computing down into ways that it couldn’t be wholesale patented too early to gain wide adoption. And thank you for helping keep the mutually assured destruction from happening and for inspiring generations of scientists in so many fields. I’m stoked to be alive and not some pile of nuclear dust. And to be gainfully employed in computing. He had a considerable impact in both.


Debug!

     10/17/2021

This episode I face my greatest fears: computer bugs. We are going to dive into the origin of the term, and examine the origins of debugging. The simple fact is that as soon as computers hit the scene we start finding bugs. Debugging follows very soon after. That part's not too surprising, it's the specifics that get interesting. Modern debugging methods we still use today were first developed on ENIAC, a machine that's anything but modern.


(OldComputerPods) ©Sean Haas, 2020