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

[Ben Nizette]

> > > 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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