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Australia Hardware Technology

Looking Back At Australia's First Digital Computer 88

An anonymous reader writes "Sometimes, it's the oldest machines that are the most fascinating. PC & Tech Authority has posted this gallery of photos of the first automatic electronic stored-program computer in Australia and one of the first in the world — CSIRAC. The photos show a machine massive in size — the main system comprised nine steel cabinets containing 2000 valves that weighed over 7000kg. Using valve technology and World War II radar systems as a starting point, the machine was used for various purposes including weather forecasting, forestry, loan repayments and building design. It boasted a 1000Hz memory clock and a serial bus that transferred one bit at a time. The system generated so much heat, cool air needed to be blown up through the cabinets from the basement below. In addition to being Australia's first computer, it is also said to have been the first computer to play digital music anywhere in the world. When CSIRAC was turned off for the last time, a witness described it as 'like something alive dying.'" Museum Victoria has some short but informative pages about CSIRAC, too, including this one about programming the thing, and another about the dangers and annoyances of working on it.
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Looking Back At Australia's First Digital Computer

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  • "a serial bus that transferred one bit at a time." .. good one.
  • Groan,

    A serial bus can be more than one bit wide, but never mind....

  • 1000 Hz - you could come very close to hand-cranking it!


    • Re:1000 Hz (Score:5, Funny)

      by Anonymous Coward on Saturday June 16, 2012 @08:47AM (#40343629)

      1000 Hz - you could come very close to hand-cranking it!

      Dude, if you can come close to hand cranking something 1000/second you should really think about not masturbating so much.

  • mercury delay (Score:3, Interesting)

    by busyqth ( 2566075 ) on Saturday June 16, 2012 @08:15AM (#40343515)
    In 1949, mercury delay line memory was ok, but by 1955 it was hopelessly outdated.
    I'm pretty surprised they didn't retrofit with core memory at some point, but then again, the rats nest of wiring in those photos doesn't inspire a lot of confidence in the upgradeability of the system.
    • by AHuxley ( 892839 )
      Australia did not have a GCHQ or NSA budget at the time :)
      • Re:mercury delay (Score:5, Informative)

        by mister_dave ( 1613441 ) on Saturday June 16, 2012 @09:44AM (#40343859)

        I think the first post war British computer was developed by Lyons [], a food retailer/wholesaler/manufacturer. If memory serves, the British Government of the day rented it for batch jobs. :-)

        There's a good book about it, A Computer Called Leo: Lyons Tea Shops, and the worlds first office computer [].

        • I think the first post war British computer was developed by Lyons,

          Then you are very poorly informed. The Leo was preceded by EDSAC 1, EDSAC II, ACE, and several other machines whose names I forget. Leo was, as the article says "The world's first Office computer". However, the Leo was an amazing development (as were the others for their time).

          this Australian machine sounds like it was derived from EDSAC I, which dates from 1946.

          • Then my memory was at fault. However, wikipedia [] reminds me that Lyons contributed finance to EDSAC.

            Standingford and Thompson saw the potential of computers to help solve the problem of administering a major business enterprise. They also learned from Goldstine that, back in the UK, Douglas Hartree and Maurice Wilkes were actually building another such machine, the pioneering EDSAC computer, at the University of Cambridge.[1]

            On their return to the UK, Standingford and Thompson visited Hartree and Wilkes in

      • Actually, it's worse than that. Australia was still officially a British colony at the time (technically, it remained so until 1986), and was under intense pressure from the British government not to pursue computer research.

        CSIRAC did have a few innovations, though. It was the first computer musical instrument, and ran one of the first high-level languages. Well, high-level by the standards of the day.

    • My first introduction to the concept of mercury delay lines was Cryptonomicon. Fun to see an actual computer that used these.

    • by hey! ( 33014 )

      Well, magnetic core was pretty new back then. Choosing to go with mercury delay lines is the kind of choice you'd make as a designer because you were familiar with the technology and were confident it would do the job. Cambridge (UK) University's EDSAC was very similar to this Australian beast and successful computer that operated between 1949 and 1958; it's successor EDSAC 2 operated until the mid 60s. Despite being archaic in certain details (memory storage, logic circuitry) these were very architectural

      • Well, magnetic core was pretty new back then. Choosing to go with mercury delay lines is the kind of choice you'd make as a designer because you were familiar with the technology and were confident it would do the job.

        In 1949, that was true.
        But it was not uncommon for 1st generation computers to be modified several times over their operating lifetime to support newer technologies.

    • CSIRAC's design was probably very tightly coupled to the characteristics of those delay lines. If you look at all the pictures you'll see that there are even (shorter) delay lines which are part of the ALU. Upgrading would have amounted to a floor-up redesign -- and there were better technologies breaking out for all the parts of the computer, not just the delay line RAM.
  • by It took my meds ( 1843456 ) on Saturday June 16, 2012 @08:15AM (#40343521)

    Please note CSIRAC was developed by the CSIRO. Yes this is the same organisation that some people have unfairly labelled as a patent troll regarding their licensing claims over technology they developed in relation to Wi-Fi. The CSIRO is a wonderful organisation that Australians should rightfully feel very proud of as they have long rich history of developing technologies that push the boundaries of science and benefit humanity. Take a look at [] to see the great volumes of innovation and excellent achievements of the CSIRO.

    Disclaimer: I work at the CSIRO and I feel immensely privileged to work in an organisation that not only developed CSIRAC, but is devoted to advancing society through a multitude of diverse cutting edge scientific research endeavours.

    • by Anonymous Coward

      I've seen CSIRAC at the Melbourne Museum, and it's quite an astonishing sight. It's in its a room dedicated to early computing, and the scale of the machine is something you can't appreciate unless you see it in person.

      As for people dissing the CSIRO, get a grip! It's one of the foremost scientific research bodies in Australia, and is responsible for a number of inventions that have benefited _everyone_ (look it up on WIkipedia if you care). It's rare these days to find government-funded science/research or

    • by csirac ( 574795 )

      I believe it was CSIR back then, which is probably for the best because CSIROAC just wouldn't have the same ring to it :-)

      I actually read about CSIRAC in highschool, at which time I thought it'd be fun to use as an online handle.

      Funnily enough I now also work at CSIRO, joining 9 years after I'd already adopted the csirac handle. I've really appreciated the creative freedoms I've had, which has resulted in very productive tangents that we've developed as open source. This would not have been possible without

    • I had the privilege of working on a project there for a few months. I have to say that the CSIRO is one of the institutions that Australians should be most proud of, but unfortunately, most have little idea of what it is or what kind of work goes on there.

      Whatever you're working on, keep up the good work!

  • by Scoldog ( 875927 ) on Saturday June 16, 2012 @08:31AM (#40343567)
    In 1955, it was the first computer in the world to play music. Coincidentally, 1955 was the first time the RIAA tried suing a university.... for 1 million dollars!
  • CSIRAC @ Caulfield (Score:3, Informative)

    by dregs ( 24578 ) on Saturday June 16, 2012 @09:02AM (#40343675)

    Interestingly, all the CSIRAC history forgets to mention it was located at Chisholm Institute of Technology's Caulfield campus (now Monash) for a long time as a display of one of the earliest computers ever made. I worked there and had the keys into the display, I now wish I'd added a bit of graffiti to the mercurary delay lines.

  • CSIRAC (Score:5, Interesting)

    by OzPeter ( 195038 ) on Saturday June 16, 2012 @09:06AM (#40343697)

    I have sitting right in front of me a copy of:

    University of Melbourne
    Computation Laboratory
    Programming Manual
    for the Automatic Electronic Computer
    (based upon papers by T.Pearcey and G.W.Hill)
    August 1959

    It's only 36 pages long, but is a fascinating read describing the internals of the computer as well as source code for things like division, sin and other fundamental things. I only have it because a company I was working for in the late '80s was about to throw it out in the trash and I walked past at the right time and grabbed it.

  • Why not play with the emulator now CSIRAC Emulator [] Very cool !
  • More on its history (Score:4, Informative)

    by thogard ( 43403 ) on Saturday June 16, 2012 @10:02AM (#40343955) Homepage

    There is a book about it :
    McCann, D. and Thorne, P. 2000. The Last of the First: CSIRAC: Australia's First Computer. Department of Computer Software Engineering, The University of Melbourne.

    Too bad there is no ISBN so I have no idea where to get a copy outside of the Melbourne Museum where the machine is currently pretending to work.

    In the second picture [] you can see a wood case with boxes. That is its /lib and the smaller box is its /usr/local/lib. There are paper tapes inside cardboard boxes with libraries of functions such as multiply integer and real square root.

    Its "assembly language" sort of looked like "(D0)->H1" for save 10 input bits into H. That was later changed to "0 D HL". "103 -> S" was changed to "3 7 K S" which is jump to address 103 or Jump 3x32+7. Of course there was no assembler in the early days so it was all punched using tables.

    The mercury delay lines are interesting. You can put about half a kbit in one tube but you have to keep refreshing it as the sound of a bit goes from one end to the other and then gets regenerated.

  • by hey! ( 33014 ) on Saturday June 16, 2012 @10:15AM (#40344007) Homepage Journal

    the main system comprised nine steel cabinets containing 2000 valves that weighed over 7000kg

    By my math that's about 14000 metric tons in valves alone. That's 80% of the displacement of the HMS Dreadnought, the first modern battleship.

  • In case someone reading the article is too young to recognize the term, a "valve" is an electron tube, one of those things that would sometimes have to be replaced in the back of a radio or TV set. Yes, they got quite hot and any large array of them required special cooling. Even a radio or TV set could warm a room.

    • Yeah, the full term is "thermionic valve". This is the British expression for what Americans call a "vacuum tube". Though I'm American, the British term seems to better describe the device's function.
  • The photos are interesting.

    In keeping with the traditions of most tech oriented sites, the comments rapidly devolve into political rants and pro/anti Apple statements.

  • > weighed over 7000kg

    Actually, it weighed over 15400 lbs. []

  • by ortholattice ( 175065 ) on Saturday June 16, 2012 @11:16AM (#40344367)

    One thing I've never understood is why these early computers (apparently) used power-hungry standard vacuum tubes, requiring huge cooling systems, rather than the vacuum tubes used in portable radios.

    In the 1930s/40s - not sure when - battery-operated radios (portable for going to the beach, as well as non-portable for people who had no electricity before rural electrification) were common. These had vacuum tubes with a filament voltage of 1.1-1.5VDC at maybe 50mA; the filament served as the cathode to conserve power. The B+ battery was anywhere from 22.5V to 90V and, because they were expensive, were expected to last a long time. The tubes had numbers of the form 1xx, like 1S5 (a pentode/diode).

    So 2000 of these would use only about 150 watts for the filaments, which is less than many modern desktops. I don't have a number for the B+ power consumption. I vaguely recall from a schematic I saw ages ago that there were high-valued resistors, maybe around 10K-100K ohms, in series with some of the plates in the low-level signal circuits, so it might not have been very much. Maybe someone else knows.

    Of course higher-power tubes might be needed to drive the I/O such as relays etc., but it seems the main logic circuitry could have been relatively low power.

    • Perhaps because the low-power tubes were considered unsuitable for computing applications? Vacuum tubes in digital switching circuits have quite a different workload from those used in radios as amplifiers. The low-power tubes may not have provided fast switching performance, or they may have been unreliable in switching circuits. I'd think that power usage was a secondary concern for the designers of these computers; reducing it would be nice, but not at the cost of speed or reliability.
    • Because those battery tubes, to achieve their low filament-power consumption, used directly-heated cathodes (as you noted). If you think about this a bit further, you'll realize that this greatly limits the number of circuit topologies, because all of the cathodes in every tube must be connected together via the filament power supply. Imagine constructing logic gates where every transistor's emitter had to be directly connected to ground. Do-able, but limiting.
      • I'm not sure that's a sufficient reason. All Valves are "N-type", and a typical bipolar logic gate (or bistable) using only NPN transistors does indeed ground the emitters. The reason for indirect heating of the cathode isn't really about biasing (especially if a negative supply rail exists), but about allowing cheap, unrectified AC supplies to be used for the heater without introducing hum into the signal. For a battery-driven radio, this problem vanishes.

        Incidentally, I recently built a battery-powered va

    • Reliability was the highest priority among first-generation computer designers when choosing radio tubes (also called valves). J. P. Eckert was co-designer of the ENIAC, which was the first thing that might be called a working computer. Eckert spent a lot of engineering time on tube reliability. He selected tubes that seemed especially long-lasting and likely to work correctly out of the box. He drove them with circuits that treated them as gently as possible: lower voltages to preserve filaments, for exam
  • Interesting fact: The micro that runs the blinkenlights on the CSIRAC panel these days has more grunt than the original computer. The things you learn at Linuxconf...

    Vik :v)

  • Image #14 is labeled as a "console teleprinter." It is really a storage drum, which was a a geometric alternative to the disk drive. Drums had a row of fixed-location heads for recording and playback. There was one head per track, which eliminated the moving arm. I once had a similar drum from an IBM 610 "calculator." It weighed about 30 pounds and stored 1,200 BITS. Perfect doorstop.

"The Avis WIZARD decides if you get to drive a car. Your head won't touch the pillow of a Sheraton unless their computer says it's okay." -- Arthur Miller