[sane-devel] Canon LiDE 90

[Pierre Willenbrock]

Guillaume Gastebois schrieb:
> Hello,
> 
> Pierre Willenbrock a écrit :
>> Guillaume Gastebois schrieb:
>>  > Hello,
>>  >
>>  > You can find attached a patch which works like my original code (with
>>  > different contrast and calibration between 2 scans...).
>>  >
>>  > I removed controversed comments (sorry).
>>
>> Thanks for the patch. I see that you added DAC_CANONLIDE90 at one place.
>>   This is probably needed at others places, too. (especially in
>> genesys.c, iirc the way to encode the shading calibration data depends
>> on one of the xx_type variables.)
>>
> DAC_CANONLIDE90 appears only in genesys_devices.c and genesys_gl841.c.

(i think you meant DAC_CANONLIDE35.) That is correct, but there is also 
CCD_CANONLIDE35, which is used in genesys.c when setting up the shading 
calibration data.

> 
>> Then i see the LiDE 35's GPIO initialization sequence is used. Are you
>> willing to play around with the involved bits to find the state
>> transitions that don't reset the scanner? This is not strictly
>> necessary, as the sequence works. But there may be some subtleties
> 
> If i dont add same constraint as lide 35 I get black image output.

see? mine does simply "powercycle" when trying to use it without that 
(not so) "magic" sequence.

>> hiding there. Try adding delays between the state transitions when
>> testing that, fast switching through the sequence sometimes leads to
>> inconsistent results. (By "state" i mean the state of the gpio pins
>> configured as output.)
>>
> How to do that ????

I used my small test program[1], modified to exercise the transitions of 
interest. As i mentioned above, my scanner is pretty unforgiving to the 
wrong sequence, so the program failed early when something went wrong.

>> For the LiDE 35 i found at least these constraints(i had a small state
>> table that showed the allowed transitions, but i can't find it now):
>> - GPO17 cannot be switched on when GPIO8 is off
>> - GPIO9 cannot be switched off when GPIO8 is off
>>
>>  > I see in some case that my scanner locks writing : "[genesys]
>>  > sanei_genesys_read_register (0x41, 0xf4) completed" and to unlock I have
>>  > to push one of the 4 buttons !!!!!! Idea about that ?

replugging does help, too? (If not, this may be interesting)

>> The scan is not starting for some reason. I don't know what causes that.
>> May be a power issue, depending on correctly setting the gpios or sth
>> like that.
> 
> The windows snoop may say that but I remember fixing gpio regs with thos
> snoop....
> Must be investigated but later.
> 
>>  > Regards
>>  > Guillaume
>>
>> Regards,
>>    Pierre
> 
> It remains the bigest problem : calibration. Because I get different
> contrast and sometimes vertical contrasted lines (bad shading). To be
> continued.

Another problem is the duplicated nibble in the data from the afe.

At least now there is a patch enabling basic support for this scanner, 
which could be integrated into sane without causing the other scanners 
to stop working.

> Regards
> Guillaume

Regards,
   Pierre

[1] http://pirsoft-dsl-dropzone.de/canon-lide35.tbz2