Accessing a USB device

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how do you access a usb flash drive?
----- Original Message ----- 
From: "Joseph C. Lininger" <jbahm@xxxxxxxxxx>
To: "Speakup is a screen review system for Linux." <speakup at braille.uwo.ca>
Cc: "Speakup Distribution List" <speakup at speech.braille.uwo.ca>
Sent: Wednesday, June 22, 2005 10:07 AM
Subject: Re: Accessing a USB device


> Chuck,
> In order to help you out, I need to see the following information. You
> can send it to me privately so as not to clutter the list. We can then
> post a solution to the list if people are interested. For all these
> tests, do them as root after the usb device is plugged in.
> 
> 1. The output from the command "dmesg"
> 2. The output of the command "lsusb -v"
> 3. A complete listing of your /dev directory, including all
> subdirectories. This command will give you what I want. "find /dev"
> 
> Equal causes can produce very unequal effects.
> Joseph C. Lininger
> jbahm at pcdesk.net
> Verification: 5eab38a77ac40416e075be8f50607ff7
> 
> And so it came to pass that on Wed, 22 Jun 2005, Charles Hallenbeck said
> 
>> I am trying for the first time to access a USB device and having a
> problem
>> doing so. The device is my new UPS from American Power Conversion,
> which I
>> plan to monitor with a program called apcupsd. The manual describes
> how to
>> configure my system for USB and how to test the USB interface before
> running
>> the program, and that is where I am stuck.
>>
>> It appears to me to be an interrupt problem. Here is why I think so.
> For the
>> past month or two I have noticed a peculiarity that happens within
> about a
>> minute after booting up the computer. Normally I start logging in
> various
>> users on difference consoles, and while I am doing that, I get a
> spontaneous
>> message saying that IRQ 5 is being disabled. The message says
> something cute
>> like, "Nobody cares!" and then disables IRQ 5. Examining the IRQ
> assignments,
>> I see that the only device assigned to that IRQ shown in
> /proc/interrupts is
>> the uhci-hcd driver. That has not been a problem until now, since
> until now I
>> have not attempted to access a USB device, which requires the uhci-hcd
>> driver.
>>
>> When I plug the cable from my UPS into a USB slot, the device is
> correctly
>> identified by manufacturer, serial number, etc., but then it says that
> it
>> fails to register with usbcore. And the test program confirms that the
> device
>> cannot be accessed.
>>
>> My kernel is 2.6.11.6, and all the relevant drivers are compiled into
> the
>> kernel. It looks to me like the uhci-hcd driver has been assigned to
> IRQ 5
>> but is not responding to that interrupt when it occurs. If someone has
> seen
>> this kind of thing before, or has any suggestion how to proceed with
>> troubleshooting this one, I would sure appreciate hearing about it.
> The
>> software I plan to run to monitor the UPS is not involved here as yet,
> since
>> I have to resolve the USB interface to the UPS before there is a hope
> in hell
>> of that software working. If it would be of value to share any of the
> error
>> messages or other data, I would be happy to do so.
>>
>> Any ideas? I have run out.
>>
>> Chuck
>>
>>
>> --
>> The Moon is Full
>> But you can still get downloads from http://www.mhcable.com/~chuckh
>>
>> _______________________________________________
>> Speakup mailing list
>> Speakup at braille.uwo.ca
>> http://speech.braille.uwo.ca/mailman/listinfo/speakup
>>
> 
> 
> _______________________________________________
> Speakup mailing list
> Speakup at braille.uwo.ca
> http://speech.braille.uwo.ca/mailman/listinfo/speakup
> 
> 
> -- 
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