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    SubjectRe: [offtopic] Re: I2c was: Cobalt Micro (was Re: Build your own Mo therboards)
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    >Further, since everything is done in software, fast machines can send
    >data faster than slow machines can receive it. This means the fast
    >machine must artificially slow down data transmission to match the
    >slowest receiver.
    >
    >This is an awful bus in all respects.

    You're missing the point that IIC was intended as a bus that could be easily
    and cheaply implemented on small ICs. It uses only two wires - pins are
    expensive. The protocol is intentionally basic so you can use a fairly simple
    state machine to run it. Incidentally, it's simply not true to say that
    "everything is done in software". It's true that IIC *can* be implemented
    purely in software, but then so can RS232.

    IIC was never designed to be a general data interconnect system. The original
    application was control of smart peripherals that didn't have or need a full
    address/data bus, such as serial EEPROMs, real time clocks, teletext decoders
    and the like.

    >Since two (or more) parties can think the bus is free at the same
    >time, clashes are possible. This will hang the IIC bus. Therefore,
    >once the bus is crashed, both parties have to reinitialize their
    >controllers to

    IIC just doesn't support more than one master in any sensible way. Again this
    was something that was never intended to work - you can't have two people
    driving the clock at the same time.

    p.



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