I am trying to use the SG_IO ioctl from the scsi driver to read and 
write raw
data to this USB hard drive (IO Data USB HD). I have googled the device 
name and
only came up with 13 sites, none of which had any information for this 
problem.
This is a link to a reseller in California who sells the device I am using
http://www.devicenet-usa.com/product_en.html#hdp

To verify that the data was not being written from the device or read 
from the device,
I used a protocol analyzer connected to the hard disk While sending the 
read or write
commands using SG_IO, there was no activity on the disk. I have also 
used a program I wrote
that reads individual sectors from a disk and displays the data in a 
format similar to hexdump.
The output from that program is also attached, in the file named data. 
As you will see, I did a read
several times from sector 0, receiving different slightly different 
values every time.

I am attaching output from dmesg gathered while connecting and reading 
from the device.


Where should I go from here? Are there other debug messages I can enable 
within the scsi generic drivers.


Dario Oliva