[sane-devel] Canon MF8330

[Teemu Suikki]

Hmm, no. I can scan any part of the paper, as long as the scan size is
so small that the data fits under 65536 bytes.  Anything higher
fails..

I don't understand what happens, it all looks fine in the logs, until this:

[pixma] read_image():reader task closed the pipe:0 bytes received,
1681920 bytes expected
scanimage: sane_read: Error during device I/O

This happens exactly when received data hits the 65536 bytes mark..

Do other devices use >64k chunk sizes? is it possible that there is a
16bit counter used somewhere where it shouldn't..

--
Teemu


2011/12/3 Teemu Suikki <zuikkis at gmail.com>:
> Hi,
>
> I tried scanning smaller area, with
>
> SANE_DEBUG_PIXMA=25 scanimage -l100 -t100 -x50 -y50  --format=tiff
>>test.tif 2>debug
>
> And surprisingly it worked! :) Perfect scan. So probably the "full
> page" settings are somehow out of bounds, I need to figure that out.
>
> The scanner was "stuck" for maybe 30 seconds after the scan, saying
> "scanning" even when the scan had already competed. I noticed that
> windows driver always sends cmd_abort_session after scanning; adding
> this fixed it on Sane as well.
>
> Anyway, looks very promising now. I updated http://zuik.org/sane/ with
> the latest files.
>
> --
> Teemu
>
> 2011/12/3 Teemu Suikki <zuikkis at gmail.com>:
>> I now started digging this myself with UsbSnoop. MF8330 really is
>> using this 0xd460 instead of 0xd420, as data transfer command.. I
>> couldn't find any other big differences.
>>
>> I modified pixma_imageclass.c to use d460.. it almost seems to work,
>> but there isn't enough data coming from the scanner. For full A4 scan
>> at 75dpi, scanner only sends about 65536bytes of data total.. After
>> that, scanimage reports:
>>
>> [pixma] read_image():reader task closed the pipe:0 bytes received,
>> 1683840 bytes expected
>> scanimage: sane_read: Error during device I/O
>>
>> Why does it say 0 bytes, it's actually 65536?
>>
>> Also in the log there are many "empty"  data packets, that are not
>> there on windows log:
>>
>> [pixma] OUT  T=4.841 len=11
>> [pixma]  00000000:d4 60 00 00 00 00 00 00  04 00 06
>> [pixma]
>> [pixma] IN   T=4.845 len=8
>> [pixma]  00000000:06 06 00 00 00 00 00 00
>>
>>
>> I have the UsbSnoop.log, sane debug output and the modified source available at:
>> http://zuik.org/sane/
>>
>> --
>> Teemu Suikki
>> http://www.ksportfinland.com
>> http://www.z-power.fi/
>
>
>
> --
> Teemu Suikki
> http://www.ksportfinland.com
> http://www.z-power.fi/



-- 
Teemu Suikki
http://www.ksportfinland.com
http://www.z-power.fi/