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SubjectRe: VIA IDE driver, v1.5 (final)
Hi!

> > > Fortunately all UDMA transfers are protected by safe enough CRC to see
> > > if a transfer fails. This way you can know your cable won't do UDMA/66
> > > and switch to something slower. (UDMA/44 seems to work on most 40-wire
> > > cables just fine). If that doesn't work, go even lower. Something like
> > > modem autobauding ...
> >
> > If it'll work like modem autobauding here (connect with speed limit=14400
> > and get 1.5Kbytes/second, connect with 33600 and spend 95% of time for
> > retrains and thus transfer with 0.1Kbytes/second speed in the end) then
> > better not...
> >
> > P.S. Sorry, could not resist...
>
> :)))))))) It'd be like this if you let UDMA/66 enabled on a 40-wire
> cable. What I meant is that after a *single* CRC error the speed would be
> lowered to the next lower step (UDMA 100, 66, 44, 33, 16) and if even
> UDMA/16 doesn't work, then fall back to PIO.

That seems wrong. If you have server capable of UDMA/66 and you run it
for year or so, you are likely to find it in PIO mode. Not good.

Pavel
--
I'm pavel@ucw.cz. "In my country we have almost anarchy and I don't care."
Panos Katsaloulis describing me w.r.t. patents at discuss@linmodems.org

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