[sane-devel] CanoScan N650U (plustek backend) not working with Mac OS X 10.3.2 build 7D24

[Henrik Rintala]

Thanks for the informative answer.

>> found USB scanner (vendor=0x04a9 [Canon], product=0x2206 [CanoScan], 
>> chip=LM983x?) at libusb:024:002
>
> The question mark after the chip id is a bad sign. It means, that
> sane-find-scanner was unable to actuall talk to the scanner. It could
> get its didentification but sending commands failed (usually because
> the interface couldn't be claimed).
>
>> Henrik-Rintala:/usr/local/bin shr$ ./scanimage -L
>>
>> No scanners were identified. If you were expecting something 
>> different,
>
> [...]
>
> Try enabling debug message. E.g.
> export SANE_DEBUG_PLUSTEK=255
> export SANE_DEBUG_SANEI_USB=255
>
> To reduce the number of USB messages, diable everything but plustek in
> dll.conf.
>
> There have been some reports that enabling debugging "fixes" libusb
> problems on MacOS X in some cases. Even if it doesn't, you should get
> a debug log that shows the exact error message.

It seems that when I use export "SANE_DEBUG_SANEI_USB=x" where x => 5 
then the scanner is detected (chip=LM9832) and I can begin scanning. 
However, even though the scanner seems to "scan" the whole document, 
only part of it is saved to the file I specified. In every case, the 
file is exactly 110592 bytes and shows only about 1/3 of the document 
to be scanned (a book cover) in a quite low resolution. The file size 
is the same regardless of the file format specified (tiff or pnm). 
Also, the scanner light does not turn off and the scanimage process 
seems to "hang", i.e. nothing happens anymore on the terminal window I 
was using so I need to open another window to kill the process.

Maybe there is some easy solution which I could try out since it 
already works partially.

Thanks a lot in advance!

        //
        \\         Henrik Rintala
        //         henrik at rintala.de
        \\         shr at mac.com
        //
        \\         http://www.rintala.de
        //
        \\