back to article RIP Danny Cohen: The computer scientist who gave world endianness meets his end aged 81

The computer scientist who created the first visual flight simulator, gave us the compsci concept of endianness and whose pioneering work blazed a trail for modern VOIP services has died at the age of 81. Dr Danny Cohen worked on one of the first ever computer-based flight simulations in the early 1970s, an era where most …

  1. J. R. Hartley

    Endian of an era

    So he's the reason we dont have AmigaOS on x86 :/

    1. Dan 55 Silver badge

      Re: Endian of an era

      No, that's definitely Intel's fault.

      1. Graham Dawson Silver badge

        Re: Endian of an era

        I'm pretty sure it's commodore's fault.

        1. Anonymous Coward
          Facepalm

          Re: Endian of an era

          From what I read it was a problem with the scalability of the co-pros Agnus, Denise, Paula and the rest.

          Apparently they were just so solidly locked into the architecture that they couldn't hope to compete anyway (even if they hadn't been so badly managed by the big C) with the performance gains being made in the PC world.

          I sold out my tasty A1200 setup to buy an Escom 486DX2/66 (irony huh?). My first foray into x86. I had to regularly rebuild it. Seemed to solve problems with. Lots of ribbon cables, VESA cards. MB Jumpers, Badly fitted case. Really just a useless nightmare. Couldn't even play an MP3 in WFWG 3.11 without stuttering all the time.

          I sorely regretted selling the Amiga.

          1. Dan 55 Silver badge

            Re: Endian of an era

            Apparently they were just so solidly locked into the architecture that they couldn't hope to compete anyway (even if they hadn't been so badly managed by the big C) with the performance gains being made in the PC world.

            Mehdi Ali ruined Commodore, R&D slowed to a crawl under his reign. But this is rather off-topic.

          2. J. R. Hartley

            Re: Endian of an era

            No, it was because of the big endian / little endian differences. That's why AmigaOS went to PowerPC.

          3. defiler

            Re: Endian of an era

            Scalability of the copros was a serious issue. I read somewhere that the malloc() call in the OS would hand over memory but not actually verify if it was unused by another application. So if you wanted speed and stability, you bypassed the OS and went bare-metal. Problem is, that meant you programmed the custom chips directly instead of via an API, so when AGA appeared, half of the hacks stopped working.

            I remember the quote in Edge magazine went along the lines of "half the A500 software doesn't work, but we don't know which half", which hardly inspired confidence.

            If malloc() had worked properly then the API would have been useful, and could have been made backwards-compatible when AGA appeared.

            Also, David Pleasance shows little hesitation in pointing out just how hard Mehdi Ali fucked up Commodore.

            1. Dan 55 Silver badge

              Re: Endian of an era

              There was no MMU on most Amigas. The problem wasn't apps using malloc(), the problem was apps not using malloc() overwriting the memory reserved by the apps which behaved. Or maybe a bad libc malloc() implementation - AllocMem() was the real OS call.

              1. defiler

                Re: Endian of an era

                Never programmed an Amiga, so I reduced it to familiar nomenclature. The point being that had there been a reliable memory allocation method then people would (maybe / probably?) have programmed for the APIs rather than hacking the silicon directly. And then those APIs could have been made backwards-compatible when AGA appeared.

                I appreciate that all of this is trying to push back the tide. Intel wasn't holding back for anyone, and Cyrix and AMD were dragging that train along pretty fast at that time. Shame that so many of those non-x86 architectures got steamrolled in the end.

                1. Dan 55 Silver badge

                  Re: Endian of an era

                  There was a reliable memory allocation method for well behaved apps. If you're talking about hitting the custom chips then to be honest if you wanted to watch a demo or play a game you very rarely had had Deluxe Paint or Word Perfect running in the background anyway.

                  Later OSes had better APIs for accessing to the custom chips IIRC.

  2. monty75
    Joke

    So sad, he was only 18.

    1. asphytxtc
      Pint

      Kudos on you sir! That gave me a proper chuckle!

    2. elaar

      Superb joke, made me laugh, but wouldn't he have been 138?

      1. Phil O'Sophical Silver badge
        1. Michael Wojcik Silver badge

          I hate to be the guy explaining the joke, but it's been a day, so...

          8110 = 010100012

          100010102 = 13810

          It's a bitwise endian reversal. (Nibblewise, which of course also works if you do it in hex, it'd be 21. In octal, it's a palindrome, so the endianness of the octal representation doesn't matter in this case.)

          In (traditional packed) BCD, it'd be 08 1C in hex representation, possibly with A, E, or F instead for the final nibble, which represents the sign. With a bytewise endian reversal that would be 1C 08, but C isn't a valid BCD digit and 8 isn't a valid sign nibble. If you did packed BCD without a sign nibble, 81 would be the single byte 81 in hex, so there's nothing to reverse bytewise and nibblewise you just get the same result as with the decimal representation (which BCD is, after all).

          I think I've thrashed this deceased equine sufficiently. Gray code, etc, is left as an exercise for the reader.

      2. rsole

        But only in binary.

    3. Anonymous Coward
      Joke

      At the funeral

      I have visions of the Big Endians and Little Endians coming together to reconcile at his funeral by providing pall bearers. One side will face one way and the other side the other...

      1. BebopWeBop

        Re: At the funeral

        Didn't Jonathan Swift write about the conflict between the big endians and the little endians?

        1. Anonymous Coward
          Anonymous Coward

          Re: At the funeral

          "Didn't Jonathan Swift write about the conflict [...]"

          In Gulliver's Travels (1726 ):

          "The novel further describes an intra-Lilliputian quarrel over the practice of breaking eggs. Traditionally, Lilliputians broke boiled eggs on the larger end; a few generations ago, an Emperor of Lilliput, the Present Emperor's great-grandfather, had decreed that all eggs be broken on the smaller end after his son cut himself breaking the egg on the larger end. The differences between Big-Endians (those who broke their eggs at the larger end) and Little-Endians had given rise to "six rebellions ... wherein one Emperor lost his life, and another his crown". The Lilliputian religion says an egg should be broken on the convenient end, which is now interpreted by the Lilliputians as the smaller end. The Big-Endians gained favour in Blefuscu. "

      2. Anonymous Coward
        Anonymous Coward

        Re: At the funeral

        1 little, 2 little, 3 little Endians

        4 little, 5 little, 6 little Endians

        7 little, 8 little, 9 little Endians

        10 little Endian boys

  3. Blackjack Silver badge

    War about eggs

    He was ahead if his time, maybe a bit too far ahead, he would have made a killing if he had decided to work for Microsoft or Apple.

    Flight simulators? We got the guy who invented flight simulators!

    Skype? Who needs to buy Skype? We got the guy who invented digital phone calls!

    But alas, that wasn't the case.

    https://youtu.be/DnbxBiw-93k

  4. Ken Moorhouse Silver badge

    Flat Earth Society

    So he believed in Logical/Arithmetic Shifts, but not Bit Rotation?

  5. Will Godfrey Silver badge
    Unhappy

    Bittersweet

    Not a bad age, for anyone, but a truly horrible way to go - to slowly lose physical control while still being fully alert.

    R.I.P indeed.

    1. Snarf Junky

      Re: Bittersweet

      Exactly what's happening to my mum at the moment. Parkinsons is an absolute twat!!!

  6. arctic_haze
    Unhappy

    Flat Earth Society?

    I do hope this was a joke and not a side effect of the Parkinson disease.

    Otherwise from that, we have really lost one of the giants who created the net we all use.

    1. Danny 2

      Re: Flat Earth Society?

      I'm a Reverend in the Universal Life Church. I can marry you in certain US states but I lost interest when I was told I needed your permission. Of course it was a joke.

      In my twenties I was a small endian but in my forties I became a big endian.

      I've yet to see a realistic flight simulator - one with passengers panicking, screaming and vomiting when you lose control. I speak from experience there.

      All the media report the best joke of the Edinburgh Fringe. It used to be mostly an arts and music festival, and the headlines would be 'best play of the Fringe'. Best joke of the Fringe was 1989, Will Durst, I forget the joke but it was better than anything I've heard since. He picked on audience members but he was gentle with them, friendly and apologetic.

      Best joke of the Fringe this year, apparently, was a pun on tourettes and florets. The funny thing the Tourettes Society went ballistic at the comedian and demanded an apology. I can't imagine the language they used.

  7. Luiz Abdala
    Trollface

    It takes a pair of "approximately spherical" balls to join the Flat Earth Society even after discovering it was not a joke.

    I hope he had plenty of chances to troll the Society to his own amusement.

    I salute him. RIP.

    1. stiine Silver badge
      Thumb Up

      re: flat earth society membership

      No, all he proved was that they can't read, either.

    2. Jamie Jones Silver badge

      I love how they reject all scientists.

      Even the climate change deniers only reject the scientists that they don't agree with.. But flat earthers seem to reject all science. It makes sense, I suppose, however I thought that they accept planes exist, but that they are designed, built, and flown by a world wide round-world evil dark state, illuminati, masons, beta-delta-psi, tescos clubcard holding, vauxhall members club representative pizzagate paedo lizard person mole person.

      1. Fungus Bob

        Of course flat earthers believe planes exist. They think the Earth is (sort of) a plane, all that oblate spheroid stuff is just religious hokum.

  8. earl grey

    sad day, indeed

    Rip and condolences to your family.

  9. Someone Else Silver badge
    Coat

    RIP Danny Cohen: The computer scientist who gave world endianness meets his end aged 81

    Is that 0x00 0x51 or 0x51 0x00?

  10. Ian Joyner Bronze badge

    Technically born in Palestine

    No such country as Israel in 1937.

    He was certainly very accomplished.

    1. Intractable Potsherd

      Re: Technically born in Palestine

      Yes - I wondered why the word "Palestine" was omitted in favour of "the country that would become Israel" - six words instead of one, and needlessly complicated.

      1. Robert Carnegie Silver badge

        Re: Technically born in Palestine

        Some people don't like that word. It doesn't bother me: I'm not involved. It was the title when the British Empire "owned" it. And I think when the Roman Empire owned it. So...

        1. Yes Me Silver badge

          Re: Technically born in Palestine

          Actually the British Empire never owned it. It was a joint British/French Protectorate under the League of Nations. If you can catch the "Sykes/Picot" documentary that Al Jazeera is running currently, you will be surprised by the complexity and duplicity of the British involvement.

          I knew somebody (British) who specifically gave his birthplace as the Gaza Strip, during the time of that Protectorate as far as I know. The exact location probably mattered, in the small matter of obtaining a British passport. I also slightly knew Danny Cohen, who deserves all respect.

  11. bob, mon!
    Pint

    "straightforward explanations" ???

    That's all you can say about the paper? I met it in grad school in the 1980's, and still have my copy. It's delightful! Here's an excerpt:

    "Encouraged by this success, as minor as it is, the Blefuscuians tried to pull another fast one. This time it was on the VAX, the sacred machine which all the Little-Endians worship."

    Look for IEN 137 if you want to understand where big.LITTLE came from. Or here's an online copy: https://montcs.bloomu.edu/Readings/ien137.txt

    1. VulcanV5

      Re: "straightforward explanations" ???

      @ bob, mon! Thanks for being kind enough to take the trouble to provide that link. Mulling over that now-ancient typescript is not too dissimilar to Danny's flight simulator: the reading time duration is, if only for a brief time, akin to a life simulator, an experience providing insights into the existence of a remarkable human being. So sorry that his own journey here is over, but the shuddering hell of Parkinson's is no kind of life at all, for anyone.

  12. Admiral Grace Hopper

    Vale

    Without my knowing it at the time, it was down to him that I spent a pleasant few weeks getting a little-endian VAX talking to a big-endian ICL mainframe back in my youth. A happy time when I look back at it now.

    1. Anonymous Coward
      Anonymous Coward

      Re: Vale

      The IBM mainframe punched tape peripherals were no longer manufactured - but the customer had a legacy application that needed to produce 5 track Telex tape. I wrote a bit of code in an IBM Front End (Comms) Processor to make an RS232 papertape punch produce 5 track Telex tape from the mainframe application. The customer expert held the first tape sample up to the light and read it correctly. We then put it through a Telex reader - and it printed garbage.

      The IBM mainframe comms interface needed the bit order in each transferred value to be reversed. The human reader had not noticed the incorrect position of the clock track - just recognising the hole patterns that fitted plain text when looking at the reverse wrong side.

  13. BOBSta
    FAIL

    Flat Earth map error

    That flat Earth map is obviously a fake! You can't see the elephants or the Turtle sticking out from under the edge!

  14. JJKing

    Another one gone

    Another GIANT of the world gone and I never even knew he existed. What a loss. Mu apologies Dr Cohen for my ignorance of your existence.

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