[sane-devel] How to get Visioneer Onetouch 7400 working, F11 x86_64

[stan]

I bought a Visioneer OneTouch 7400 second hand at a price that was
almost like finding it in the trash.  Because the 7300 is supported I
thought it would be fairly easy to get the 7400 working.  Getting it
working was easy, it was finding the firmware that was a real bear.  I
have it working for root at this point, and thought I would document the
steps I took so other people can also get this working.  In addition,
this yields the cis3R5B1.fw firmware file, so it should help people with
other scanners that use that firmware for the gt6816 chip.

Go to Visioneer and download the 32 bit drivers for windows.  
http://www.deviceden.com/download/1469/visioneer/onetouch-7400-usb/driver/
This is in msi format, and the file was called 7400.32.408602.EN.msi
when I downloaded it.  If you have windows, you can just install it and
pull out the firmware file using the sane directions.

If you run only linux, you will need to be a bit more creative.  

Make sure that you have p7zip installed.  Create a directory to unpack
the msi in, I used msi7z, and cp it into the directory.  Cd to the
directory and run 

7z x 7400.32.408602.EN.msi

This will extract a bunch of files, not one of them which is obviously
the firmware.  However, there is a file called _StringData.  Open it in
an editor that has search (I used vim) and find the string cis3R5B1.
Look for the first C__ before that in the file. Remember the first 6 or
so characters after that C__, in my case it was 302197.

Now, run the command 

cabextract 7400.32.408602.EN.msi

This will spew a whole lot more files.  After the command is done run
the command

ls | grep 302197

This will list the file that contains the firmware.  In my case that
file was called 

_302197197C1841CFAEEE6346AB0E4996

So I just copied the file to /usr/share/sane/gt68xx/cis3R5B1.fw and
changed the permissions to +r for everyone.

At this point the firmware is in place, but the gt68xx.conf file in
/etc/sane.d/ has to be modified.  I edited it and commented everything
in the file except the following lines:

usb 0x04a7 0x04a0
#vendor "Visioneer"
#model "OneTouch 7400"
override "visioneer-onetouch-7300"
firmware "/usr/share/sane/gt68xx/cis3R5B1.fw"
# # Autodetect Visioneer OneTouch 7300
usb 0x04a7 0x0444

That is all there was to it and  I was able to run the 

scanimage > test_image.pnm 

command and it worked fine.

I am still working on setting user permission to run this scanner
automatically.  And I haven't tested beyond this, so there could be
other gotchas hiding in the details.