Re: [gentoo-user] No /dev/sda1 with Klingston usb disk. Wrong lsusb output.

[David]

On Tue, Apr 18, 2006 at 10:59:00PM +0800, Fr?d?ric Grosshans wrote:
> Le mardi 18 avril 2006 ? 11:47 +0200, Petr Kocmid a ?crit :
> > On Tuesday 18 April 2006 10:14, Fr?d?ric Grosshans wrote:
> >
> > > Any idea left ?
> >
> > So, you definitely have a hardware problem. Digging for the id of your device
> > 1043 8006 reveals a linux kernel mailing list archive thread:
> >
> > http://www.ussg.iu.edu/hypermail/linux/kernel/0410.0/0023.html
> >
> > with the identical problem: the device worked in some computer and not in
> > other.
>
> That's a bad news, since the goal of an USB stick ist precisely to move
> data from one computer to another.
>
> <reading the complete thread, at
> http://marc.theaimsgroup.com/?t=109656092700004&r=1&w=2 >
>
>  what is strange, is that the 1043:8006 was precisely the identity of
> the stick on the working computer. Futhermore, this usb stick has worked
> on the same computer.
>
> > I see two possibilities: a slave controller chip incompatibility or
> > insufficient power problem, device wants to sink more current than port
> > actually provides at +5V. Port should provide up to 500mA, while many
> > notebooks are very weak at usb power and do not keep up the standard.
> >
> > To eliminate the first one, you should seek for the computer (or maybe an
> > external usb hub) which will work with that chip.
>
> That's currently impractical for me. I may try several computers when
> I'm back home.
>
> > To eliminate the power issue on your equipment, you can try to measure
> > consumption at the +5V with some prepared usb cable or even try to feed the
> > device from an external power source. You will need laboratory equipment to
> > do it (A regulated laboratory power supply with current limitation). Ask some
> > electronics engineer.
>
> "never give up" is actually your motto !
>
> I could look for such equipement here (I'm in the physics department of
> a Chinese university), but I do not feel like it (I already destroyed to
> much electronic equipment during my PhF thesis !)
> >
> > As a first aid, try an external usb hub with it's own power supply.
> I'll try when I'm back home (in may)
If you are in Beijing, 
it is easy to do the test using an external usb hub with it's own power supply for free. Because Beijing has the biggest computer market in north of China! 
Simply, you go to one of the sereral big computer stores on the
Zhong Guan Cun street, the street is near Beijing University, and ask
for a free test with the usb hub. If it works, you can buy it with 10 or
15 dollars or cheaper!
You'd better ask your host to come with you for bargain!

By the way, I'm in Beijing now, if you are in Beijing too, you can call me for more help.:-(
>
>
> > 1G flash chips require a lot of power to operate, and not having enough is
> > consistent with your symptoms of "no media".
>
> I didn't know. I naively thought "the bigger / the better" and I don't
> really need something so big...
>
> Could that be that the power consumption of the stick increases with the
> volume of the files on it ? Which would explain the correctness of the
> first tests (with small files) and the problem when the key holds a
> bigger file...
>
> By the way, if it's a hardware problem, would it be useful to get the
> stick replaced by another of the same model ? Or is that a model
> problem ?
>
>
> 	Fred
>
>
> --
> gentoo-user@g.o mailing list

-- 
best wishes
                                                   David Chen

                                       office tel: [phone]
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