Re: Error reading usb device with libusb

On 9/13/07, Frédéric Mantegazza <[email protected]> wrote:
> Hello,
>
> I'm using a USB DIY screen calibration sensor[1] with ArgyllCMS, a free
> calibration software[2].
>
> The dialog with this sensor is very easy: just read/write like on serial
> bus. I made a python script for tests purpose, and it works fine
> using /dev/ttyACM0 (provided by cdc-acm driver).
>
> But in argyllcms, the developper used libusb, to be cross-plateform. And it
> does not work for me (it works on developper's computer). Here is what I
> get:
>
> Setting up the instrument
> hcfr: About to init coms
> hcfr: About to init USB
> icoms: About to set usb port characteristics
> icoms: About to open the USB port
> icoms: USB port needs opening
> icoms: About to open USB port 'usb:/bus0/dev92 (Colorimtre HCFR)'
> icoms: USB port is now open
> icoms: Clearing any USB errors
> icoms: usb port characteristics set ok
>
> hcfr: Doing break
> Break done, ICOM err 0x0
> hcfr: About to init instrument
> hcfr: About to read firmware version
>
> icoms: Write_Read called with '\377'
> icoms: About to write '\377' ICOM err 0x0
> icoms: Read called
> icoms: About to return read '' ICOM err 0x2000
> icoms: Write_Read Write failed - returning 0x2000
> hcfr_command failed
> hcfr: Error with getting or version of firmware
> The instrument can be removed from the screen.
> icoms: delete called
> icoms: closing port
> usb_close_port() called
> usb port has been released and closed
> dispcal: Error - dispread failed with 'Instrument Access Failed'
>
> 0x2000 is a timeout error. I tried to increase the value (up to 1 hour!)
> without success.
>
> At the same time, in the /var/log/messages, I can read:
>
> ttyS3: LSR safety check engaged!
>


This might be because the application failed to detach the kernel
cdc-acm driver.

Try the following:
http://libusb.sourceforge.net/doc/ref.nonportable.html

Regards,

Xiaofan

-------------------------------------------------------------------------
This SF.net email is sponsored by: Microsoft
Defy all challenges. Microsoft(R) Visual Studio 2005.
http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/
_______________________________________________
[email protected]
To unsubscribe, use the last form field at:
https://lists.sourceforge.net/lists/listinfo/linux-usb-users