From owner-freebsd-stable  Fri Sep  7 15:17:39 2001
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From: Dave Uhring <duhring@charter.net>
To: Randall Hopper <aa8vb@nc.rr.com>
Subject: Re: UDMA ICRC error reading fsb (?)
Date: Fri, 7 Sep 2001 17:17:33 -0500
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On Friday 07 September 2001 17:04, Randall Hopper wrote:
> Dave Uhring:
>  |On Thursday 06 September 2001 07:43 pm, Randall Hopper wrote:
>  |>      What do these messages mean?  Are CRCs done by the IDE
>  |> controller on DMA transfers and they're coming up wrong?
>  |>
>  |> ad0s2a: UDMA ICRC error writing fsbn 3283483 of 396704-396713
>  |> (ad0s2 bn 3283483; cn 204 tn 98 sn 49) retrying
>  |
>  |Your drive is dying.  Back it up and replace it.
>
> Ok, thanks.  But what do these messages "mean" on a technical level?
>
> And could these just as well indicate a marginal cable, bad
> connector, loose connector, or the other hard drive on the controller
> being a bit flakey?
>
> Randall

CRC's (16 bit cyclic redundancy check characters) have been done on 
controllers since we had to use floppies.  The first Winchester drive 
interface I ever designed back in 1979 had a Fairchild 9401 (IIRC) CRC 
generator chip on it.  The writes are failing.  You "may" have marginal 
cabling or loose or corroded connectors.

If you wish to keep using the drive, replace the cable and in doing so 
your contacts will also wipe clean.

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