[sane-devel] Bug#597922: Additional Scanner Logs

[Olaf Meeuwissen]

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On 2010年12月07日 08:50, Olaf Meeuwissen wrote:
> On 2010年12月06日 09:44, Olaf Meeuwissen wrote:
>> [...]  The backend does not
>> do the right thing protocol-wise and I suggested a fix in a previous
>> comment.  Once that fix is added, you will still be out of luck because
>> your scans will be aborted by the backend as soon as it sees a cancel
>> request (the last byte of the image data block matches 0x10).  I have no
>> clue as to why it sends that information.  If all is okay you should be
>> seeing 0x00 there.  As I mentioned before, I have no information on the
>> 0x02 part of that byte here at hand but I'll see if I can dig something up.
> 
> I found an old command spec in my private archive for the Perfection
> 1650 but that only documents the 0xc0 bits of the error code.  Looks
> like not even the 0x10 bit ought to be set ever.
> 
> One option would be to mask the undocumented bits but that very likely
> would have to be done on a per scanner basis as the 0xf0 bits are known
> and documented to be supported by some scanners.  Yuck!

I checked with Epson and confirmed that the error code can safely be
masked with 0xc0 for the Perfection 1650.  This should be done before
checking any of the bit flags of course.
Also note that this is a model specific fix and should not be applied in
general.

I'll leave patching the sources to the backend maintainer (Cc:d).
- -- 
Olaf Meeuwissen, LPIC-2           FLOSS Engineer -- AVASYS CORPORATION
FSF Associate Member #1962               Help support software freedom
                 http://www.fsf.org/jf?referrer=1962
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