Usb Doesnt Always Want To Work


The only hit on google is in Chinese. I'm going to back away slowly and let someone else help debug this one. Sorry. :ph34r:
 
i have the same problem, once you see "cant enumerate device" your screwed, need to reboot. (make it hard off first, reset without powerdown wont work for me)

So usb in once only, if your not using a hub as first device, then it works via the hub.
 
It seems that the only way I can use another usb drive without powering down is to pull up the terminal and enter 'sudo umnount /media/sda1' first.
 
BDB66 said:
It seems that the only way I can use another usb drive without powering down is to pull up the terminal and enter 'sudo umnount /media/sda1' first.

If that actually works (don't have my pandora yet, so I can't try it out), I'm suprised that nobody has thought to try it before now. Just to clarify, do you have to re-mount using the terminal as well, or is that handled by the OS?
 
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So... is this a bug or not? (Accepting that there are currently un-mount issues, so if it is just mounting, USB is not a problem)

I can reliably connect/disconnect a USB2 device (android phone).
I can not make my mouse work, wither using a high speed hub (seems to work), or a OTG lead (new, un-proven).

Plugging in either the hub or the mouse shows nothing in dmesg, the hub lights up, the mouse does not. Also, lsusb seems to be broken (which should rate as a bug)
 
USB is a tempestuous mistress.

The Pandora has a USB2 host, and a USB2GO controller. Both can be used to solve your problem, but you need the right cable.

You see, the USB2 host port is always going to want to operate in USB2 HI mode, but this can be a bore on battery-life.

USB2 can switch itself to USB1 - which also incidentally has hi/lo voltage/speed modes, as well.

The battery-life/USB2 hi-speed equation/solution is this: plug a USB2 hub into the Pandora, and let the hub handle USB1 hi/lo, and UBS2 hi/lo switching *on a port basis* and let the USB2 Pandora port be useful for, say, plugging into a hub *or mostly just USB2 hi only, really truly USB2 hi, devices (like some keyfobs and so on..)

The difficulty is when the USB1 hi/lo modes are selected - this can prevent detection/proper operation of the USB2 devices, until the port is properly reset. Not all devices properly inserted into the Pandora initiate this reset of the USB2 controller for power requirements, because many devices have short/truncated USB setting structures in their firmware.

So, to answer the question: yes, the Pandora USB2 port works great - if you plug it into USB2 devices, exclusively. If you sometimes go back between USB1 and USB2 hi/lo, then you'd be better off using a HUB, which is designed by USB spec to negate a lot of this rubbish (and is thus often also referred to as a buffer device in USB topology), and so on ..
 
torpor said:
USB is a tempestuous mistress.
*blah*
So, to answer the question: yes, the Pandora USB2 port works great - if you plug it into USB2 devices, exclusively. If you sometimes go back between USB1 and USB2 hi/lo, then you'd be better off using a HUB, which is designed by USB spec to negate a lot of this rubbish (and is thus often also referred to as a buffer device in USB topology), and so on ..
You do know that the host port only has a high speed/USB2.0 controller? It is plausible that it could get very confused because of a 1.1 device, but they'll never work without a USB2.0 hub in between (because hubs have a transaction translator/TT). The OTG port OTOH should do USB1.1 host just fine with a proper adaptor.
 
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No, the USB2 is HS only. Full and lo speed devices will not work in the Pandora's host port, period. It has no capability of switching back to USB1.1. This is why a high speed hub is required. It will effectively translate the USB1.1 device's communication into USB2.0 High Speed.

Tsh: are you typing "sudo lsusb" to list USB devices? You need to be super user to get USB information, otherwise it will just return and you'll see nothing.
When you plug the mouse in via the hub, does it work? If so, then your USB host is working properly. Your mouse will never work directly with the USB host, it lacks the components required to run USB1.1 devices, so must go through the hub.
 
WizardStan said:
Tsh: are you typing "sudo lsusb" to list USB devices? You need to be super user to get USB information, otherwise it will just return and you'll see nothing.
When you plug the mouse in via the hub, does it work? If so, then your USB host is working properly. Your mouse will never work directly with the USB host, it lacks the components required to run USB1.1 devices, so must go through the hub.

Grrr. I'd seen that before, and forgot.
OK, so now
Code:
sudo lsusb
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
However, this never changes - with the hub connected to either port, with or without the mouse.
On my desktop, the hub appears as
Code:
Bus 004 Device 002: ID 0e8f:0016 GreenAsia Inc.

I am guessing that my hub is 1.1, despite the logo, and my OTG lead is broken. Wonder if the wiki lists any known good cheap hubs (or usb2 mice)
Edit: http://pandorawiki.org/USB_compatibility_list#Compact_USB_Hubs Please -any known working hubs please add...
 
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I want the smallest, lightest USB2 hub you can find. If anyone spots a good one, please share the details ..
 
torpor said:
I want the smallest, lightest USB2 hub you can find. If anyone spots a good one, please share the details ..
http://www.amazon.co.uk/gp/product/B0025X16AS
Not very small, and doesn't look great in use (2 plugs on wires). but it works, and isn't huge.
Battery life with wifi/hub/mouse - 5.5 hours. Seems to be mostly down to the hub (so the blue LED is for the chop)
 
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