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    TTL signals counter with USB


    Hello,

    I'm new to hardware development and I'm trying to understand if it is possible to count 20ns TTL signals with a standart TTL to USB Converter. Is it fast enough?

    Thanks,
    David
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    https://en.wikipedia.org/wiki/USB
    20nS equates to 50MHz.
    On the face of it, USB2.0 ought to be sufficient if you can massage the transitions into something USB understands.
    If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.
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    Originally Posted by salem
    https://en.wikipedia.org/wiki/USB
    20nS equates to 50MHz.
    On the face of it, USB2.0 ought to be sufficient if you can massage the transitions into something USB understands.

    Thanks for your quick answer
    20nsec = 50 GHz => not good enough for USB2.0

    If ill find any TTL to USB3.0 converter, Do you think it will be possible to count those signals?

    Thanks,
    David
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    I think you're out by a factor of 1000.
    1Mhz == 1uS
    1Ghz == 1ns.
    20ns can't possibly be any higher than 1GHz.
    If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.
    If at first you don't succeed, try writing your phone number on the exam paper
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    Oh right, I am wrong,
    How do you suggest reading the USB port?
    thanks,
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    Reading it like a serial port seems a good idea to me.

    You should start looking at various USB prototyping / breadboarding products, see how they work, and how you might integrate your pulse counter with them.
    If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.
    If at first you don't succeed, try writing your phone number on the exam paper

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