[Gllug] re: SCSI vs SATA

[John Hearns]

On Wed, 2004-06-09 at 15:42, Pete Ryland wrote:
> On Wed, Jun 09, 2004 at 11:51:39AM +0100, Andy Farnsworth wrote:
> >   In it's simplest form, serial needs only one wire.  However, this is
> > never used in practice as the way a signal is read is that the voltage
> > is compared to "ground".  Ground is theoretically zero volts, however in
> > reality it often has a voltage associated with it.  This is why serial
> > uses two wires, one for signal, one for ground so that both ends of the
> > communication has the same "common ground" to compare the signal line to
> > determine if it is a one or a zero.
> 
> As we all know, electricity works by having electrons flow in a circuit.
> With only one wire, we must use a "ground return" system which means that we
> have current flowing through our ground 

Wildly off topic,
but at last year's Edinburgh Fringe I saw a fantastic play about the
life of Nikola Tesla.
A lunchtime play, but it captivated me.
If you ever get the chance, go to see it. 
http://www.electriccompanytheatre.com/works-brilliant.htm

Tesla had a slight obsession with pigeons too, represented by the
actress in the play dressed up as a pigeon.

Tesla has all sorts of ideas - including global power distribution.

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