External USB drive & B3.

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mornfall
Posts: 7
Joined: 23 Jul 2008, 18:27

External USB drive & B3.

Post by mornfall » 19 Oct 2010, 19:10

Hi!

Compliments on the really nice HW & SW that is B3! Anyhow, I tried to attach an external USB drive (2.5" WD, just USB and no external power) and it this is what I see in dmesg:

[26436.898069] usb 1-1.2: new high speed USB device using orion-ehci and address 4
[26436.918650] hub 1-1:1.0: unable to enumerate USB device on port 2
[26470.694455] usb 1-1.2: new high speed USB device using orion-ehci and address 5
[26470.836038] usb 1-1.2: device descriptor read/all, error -71
[26470.865314] hub 1-1:1.0: unable to enumerate USB device on port 2
[26522.658439] usb 1-1.1: new high speed USB device using orion-ehci and address 7
[26522.780279] usb 1-1.1: device descriptor read/all, error -71

I suspect it *might* be that the USB ports do not give enough power to spin up the drive, although I am not really sure. Could be a different problem altogether... Nevertheless, it works with my laptop and I can also confirm that it does not spin up when hooked to B3. I am not sure what goes first though, so maybe it's not spinning up because of an earlier failure of something?

Thanks!

philgaskin
Posts: 51
Joined: 12 Oct 2010, 12:18
Location: United Kingdom

Re: External USB drive & B3.

Post by philgaskin » 19 Oct 2010, 19:40

I had the same problem yesterday with a 2.5" external USB disk. It is self powered by my laptop but B3 had insufficient power to drive it. I ended up using a second USB to 5v power lead in the second b3 USB port to get it to work. I guess that the b3 can't deliver the full 500mA per port which I think is the USB2 spec.

Ubi
Posts: 1547
Joined: 17 Jul 2007, 09:01

Re: External USB drive & B3.

Post by Ubi » 20 Oct 2010, 04:01

Yes, the power supply for Bubba is already 2.5A, which is more than usual, but not enough to power two HDs. There's not much you can do about it except using separate power for the external HD.

mornfall
Posts: 7
Joined: 23 Jul 2008, 18:27

Re: External USB drive & B3.

Post by mornfall » 21 Oct 2010, 05:53

Hm. The drive does not come with any other connections (just a single USB) and no external power supply or connector. So I guess though luck. I have sort of thought it would be easier to copy the data from the disk directly instead of going through a laptop and network... well, I guess I can go the more complicated route, afterall. Thanks for the info.

Ubi
Posts: 1547
Joined: 17 Jul 2007, 09:01

Re: External USB drive & B3.

Post by Ubi » 21 Oct 2010, 06:29

If you buy a powered USB hub you can connect that hd without any problems
.

Harry
Posts: 49
Joined: 12 Feb 2009, 09:43

Re: External USB drive & B3.

Post by Harry » 21 Oct 2010, 13:00

This is really interesting since I'm really considering buying a B3.

My bubba2(no wifi) that came with a 3A power supply don't seem to have any problems whatsoever with supplying power to an external USB powered hard drive.
Would a more powerful power supply connected to B3 make a difference or is it the B3 itself that is the problem?

mornfall: maybe a USB extra power cable (y-cable) would do the trick, it's a cable that is used to provide high consuming usb peripherals when using USB 1.1(or previous), it uses two USB "outlets" to compensate for the lack of power.

I know there was some kind of plans to maybe sometime prepare Bubba2 to use a USB 3g dongle as WAN, and as far as I know, those dongles can also be pretty power consuming.

I am pretty sure the specification of Usb 2.0 should allow an output of 500mA, at least thats what I always take for granted.

A statement from Excito regarding this would be most appreciated.

/Harry

johannes
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Joined: 31 Dec 2006, 07:12
Location: Sweden
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Re: External USB drive & B3.

Post by johannes » 22 Oct 2010, 09:32

This sounds strange, the USB port is designed for 500 mA (autofuse shuts off at 750mA after 1 minute), and this is measured and verified. I'll grab one from production and re-do this measurement, just in case, but my guess is that it's something else (sw?), or that your USB disks surge too much power?

I'l double check and get back. Meanwhile, I would appreciate if someone could measure the actual voltage on the USB? Does it drop below 4,6V when you insert the disk? I haven't been able to reproduce the problem here, but I'll try with more disks.
/Johannes (Excito co-founder a long time ago, but now I'm just Johannes)

Harry
Posts: 49
Joined: 12 Feb 2009, 09:43

Re: External USB drive & B3.

Post by Harry » 27 Oct 2010, 02:04

Any results yet?

/Harry

johannes
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Location: Sweden
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Re: External USB drive & B3.

Post by johannes » 27 Oct 2010, 05:00

We have measured and checked 500 mA supply from both ports, no problem. Have ordered a 2.5" disk as well, will try as soon as it gets here.
/Johannes (Excito co-founder a long time ago, but now I'm just Johannes)

philgaskin
Posts: 51
Joined: 12 Oct 2010, 12:18
Location: United Kingdom

Re: External USB drive & B3.

Post by philgaskin » 29 Oct 2010, 09:13

I was just thinking. I had the same problem trying to power an external USB 2 disk which is self-powered on all other equipment. I also have the wireless B3 model though. Could it be the wireless that is affecting it? I did manage to power the disk with a Y cable though.

Harry
Posts: 49
Joined: 12 Feb 2009, 09:43

Re: External USB drive & B3.

Post by Harry » 29 Oct 2010, 11:30

philgaskin wrote:I was just thinking. I had the same problem trying to power an external USB 2 disk which is self-powered on all other equipment. I also have the wireless B3 model though. Could it be the wireless that is affecting it? I did manage to power the disk with a Y cable though.
without owning a B3 wifi yet, I do hope that there is a simple way to turn off the wifi (security aspect etc.)
And if so, then there should be no problem to test your theory.

johannes
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Location: Sweden
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Re: External USB drive & B3.

Post by johannes » 29 Oct 2010, 14:46

Yes, wifi can of course be turned off. Howver I doubt this has anything to do with it, shouldnt be connected in any way. Give me a few more days and I'll try to figure this out. :-)
/Johannes (Excito co-founder a long time ago, but now I'm just Johannes)

Ubi
Posts: 1547
Joined: 17 Jul 2007, 09:01

Re: External USB drive & B3.

Post by Ubi » 31 Oct 2010, 05:52

I connected my unpowered WD passport 500GB drive to my B3 and it works perfectly. This of course does not solve your problem but it at least shows that it is not a systemic issue.

Ubi

johannes
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Joined: 31 Dec 2006, 07:12
Location: Sweden
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Re: External USB drive & B3.

Post by johannes » 31 Oct 2010, 07:31

Thanks Ubi for letting us know.
/Johannes (Excito co-founder a long time ago, but now I'm just Johannes)

Harry
Posts: 49
Joined: 12 Feb 2009, 09:43

Re: External USB drive & B3.

Post by Harry » 31 Oct 2010, 08:20

Ubi wrote:I connected my unpowered WD passport 500GB drive to my B3 and it works perfectly. This of course does not solve your problem but it at least shows that it is not a systemic issue.

Ubi
Does Your B3 have wifi?

/Harry

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