Re: single bit errors on files stored on USB-HDDs via USB2/usb_storage

From: Ben Nizette
Date: Sat Dec 09 2006 - 01:11:36 EST


Also, you mentioned that the corruption occurs systematically on certain
byte patterns. Therefore it's certainly not related to the cables.
It'd guess that too, but who can that say for sure. :-|

You may have a bit pattern that stresses the controllers and suddenly
a marginal cable may matter.

The errors occur in strings of 0xFFs. From the USB standard:

a “1” is represented by no change in level and a “0” is represented by a change in level

so this error-infested bytes are effectively long, quiet times on the wire. I would have thought this would be the _least_ stressful time for the controllers but maybe they are also more susceptible to noise during this period.

Regards,
Ben
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