On Tue, Oct 10, 2000 at 01:42:51PM -0400, Mark Hahn wrote:
> > > > Btw, reading the ATA/ATAPI-6 specs I think UDMA66 should work on a
> > > > setup where would be just one drive and a really short, 40-wire cable
> > > > without problems as well. I've even seen systems shipped like that.
> > >
> > > uh, what part of the spec leads you to that conclusion?
> > > I've haven't seen a draft more recent than ~1h2000, but
> > > they've been unambiguous about absolutely requiring
> > > 80-conductors for >= ata66, and that two-connector cables
> > > must be 5<=l<=18, and three-connector cables 10<=l<=18.
> >
> > ATA/ATAPI-6 draft rev. 0a, page 14 (sheet 28 of 404), table 2, row 4,
> > column 1, plus comment 4 in the same table.
>
> guess I should get a more up-to-date draft!
>
> > And from the engineering point of view, it seems reasonable, too.
>
> noise/crosstalk-wise, sure. does the new spec also permit
> a min length less than 5" between host and dev1?
The spec talks about three types of connection - "40-wire assembly",
"80-wire assembly", both being three-connector cables with the
limitations you cite. Plus it talks about a "direct point-to-point
connection" for a single device case. There isn't any minimum length
specified for that case. This may be some relict in the spec, though.
-- Vojtech Pavlik SuSE Labs - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org Please read the FAQ at http://www.tux.org/lkml/
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