[sane-devel] Re: [Linux-usb-users] Problems with HP 6200C scanner and SANE

Alan Stern stern@rowland.harvard.edu
Mon, 31 May 2004 14:58:12 -0400 (EDT)


On Mon, 31 May 2004, David Härdeman wrote:

> Hi,
> 
> I'm currently trying to get an HP 6200C USB scanner to work with SANE 
> (1.0.14) under Linux (Debian woody with some backports, kernel 2.4.26). 
> Whenever I scan something which requires a low amount of data (lineart 
> picture at 100dpi for instance), everything works just fine. But when I 
> scan a more bandwidth hungry pic, it never succeeds. I've tried this 
> both with the "scanner" module in the kernel and with libusb but both 
> seem to experience the same problems.
> 
> I have tried sane's "dumb-read" option and all other option which were 
> mentioned in the sane-hp man page but I'm running out of ideas. Any 
> clues what might cause this (might later kernels be too picky with their 
> timing requirements)?
> 
> TIA,
> David
> david@2gen.com

The most likely explanation is that some other program (possibly a hotplug 
utility) is trying to access the scanner while you're using it, thereby 
confusing the scanner and causing it to fail.  I've seen reports from 
other people where the "usbmodules" program did this.  See what happens if 
you turn off all hotplug support.

Alan Stern