problem with UDMA mode on XP1000
Andrew Gallatin
gallatin at cs.duke.edu
Mon Apr 14 06:22:24 PDT 2003
Riccardo.Veraldi at fi.infn.it writes:
> anyone has hints how I could fix this problem?
I'm re-sending something I sent a few months back when somebody else
complained of the same problem in a miata. Miata's and xp1000 have
the same form factor, all the the below applies:
Why? Well, alphas are electrinically noisy, and physically cramped.
The 500au in particular was designed by some sort of sadist who
wanted things to look pretty and didn't give a damn how things
worked on the inside. If I had a $1.00 for every drop of blood I
ever lost by skinning my knuckles inserting or removing drives or
pci cards from miatas, I'd be rich.
Rant aside, ATA cables are VERY sensative to EMI noise. What's
happening to you is that the cable is either badly twisted, running
too close to an EMI source, or both. This is causing the transfers
across the cable between the controller and the disk to be corrupted
(that's the ICRC error you're seeing). This is NOT the fault of the
software, rather its a real hardware problemn with your setup. The
software is saving you from serious disk corruption.
I suggest moving things around inside and making sure that the
cables are kink-free and don't run close to a source of EMI noise
(cpu, powersupply, other pci cards). This is much easier said than
done on a miata like yours. You might also consider purchasing the
highest quality cables you can find (I have no suggestions as to
brand..). Maybe serial ata has better sheilding and would do
better. I dunno. I do know that it took me 3 sets of cables and
considerable fiddling to get ata33 to work on a UP1000.
Alternatively, you could use atacontrol to force a slower mode like
udma66 or udma33 which the cable might be more capable of handling.
I have an old promise card in my miata which seems to handle udma33
OK.
Good luck. You'll need it.
Drew
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