SANE can't find Canon Canoscan N124OU scanner

Issues related to hardware problems
Post Reply
someotherguy
Posts: 32
Joined: 2018/08/25 20:25:39

SANE can't find Canon Canoscan N124OU scanner

Post by someotherguy » 2018/10/19 15:18:23

I downloaded and installed sane-backends-git20181014.tar.gz. I also installed libusb via yum onstall, which the SANE documentation says is required for USB scanners. sane-find-scanner fails to detect the scanner regardless of whether signed on as root or not (therefore not a permission issue). According to the SANE supported device webpage this scanner has complete support via the plustek 0.52 backend. If I unplug/replug the scanner from the Centos 7 box then check /var/log/messages, the scanner is found using xhci_hcd as USB device number 5, and the id vendor and id product numbers match those given for the scanner on the SANE device supported page.

Running sane-find-scanner in verbose mode, it says libusb was not available. Sane documentation says SANE requires libusb version 0.1.6 or newer. The version in the Centos 7 repository is apparently 0.1.4.3 something, so I removed it via yum remove and installed version 1.0.22 from a libusb website tarball. Running sane-find-scanner -v still fails to find the scanner and still says libusb is not available.

According to https://linux.die.net/man/5/sane-usb, "Libusb can only access your scanner if it's not claimed by the kernel scanner driver. If you want to use libusb, unload the kernel driver (e.g. rmmod scanner under Linux) or disable the driver when compiling a new kernel." My attempts to prevent the kernel from claiming he scanner have all failed.

I'm pretty much out of ideas. Any suggestions welcome.

User avatar
TrevorH
Site Admin
Posts: 33202
Joined: 2009/09/24 10:40:56
Location: Brighton, UK

Re: SANE can't find Canon Canoscan N124OU scanner

Post by TrevorH » 2018/10/19 15:59:31

That's a scanner from 2005 so it ought to be supported by the packaged versions in CentOS so I'm not really sure why you went off a source install rampage. Undo it all then yum install libusb sane-backends and try again.
The future appears to be RHEL or Debian. I think I'm going Debian.
Info for USB installs on http://wiki.centos.org/HowTos/InstallFromUSBkey
CentOS 5 and 6 are deadest, do not use them.
Use the FAQ Luke

someotherguy
Posts: 32
Joined: 2018/08/25 20:25:39

Re: SANE can't find Canon Canoscan N124OU scanner

Post by someotherguy » 2018/10/19 18:25:30

I did a Google search on "Linux" & "Canoscan N124OU" or something similar and found the SANE webpage. It never occurred to me to check and see if SANE was available via yum. I followed your advice, and the scanner is detected if I run sane-find-scanner when logged on as root (but not via my usual login). Major progress, and I should be able to figure it out from here. Thanks ever so much.

Post Reply