[sane-devel] Trouble with Primax 4800 Direct

[Daniel Klär]

Gerhard Jaeger schrieb:



>># scanimage --help -d plustek_pp:parport0
>>The output contains the following lines:
>>|  --mode Lineart|Halftone|Gray|Color [Color]
>>|  --resolution 50..300dpi [50]
>>|  --x 0..215mm [126]
>>|  --y 0..297mm [76.21]
>>If not specified otherwise the scanner scans with the settings in
>>brackets. I can scan with other settings, but I have to specify
>>always all the four parameters. Xscanimage also shows these
>>preferences and crashes immediately (simply disappears from screen)
>>when I try to change it.
>>I thought the values in brackets are updated, when a scan with other
>>settings is performed? How can I set the defaults?
> 
> 
> No way so far. I'm somewhat surprised, that Xscanimage will crash - need to
> test that.

I couldn't figure out why xscanimage and xsane were crashing all the 
time, so I started using scanimage. At least xsane (using the 
net:localhost device) prompts a box telling me, that the backend wants 
to have username and password. I have to test this more systematically, 
maybe next weekend or after work today.

  >
> Those scanner always do this ugly noise during calibration :(

I know, I was very surprised when I scanned my first images at high 
resolution. Now, after 4 years of using this scanner I can guess some 
scan settings from the noise that it produces. But in this certain case 
the motor simply doesn't stop where it should stop: at the mechanical 
limit of the casing. It also seems to drive to fast, so that the heigth 
of the resulting image is too small, while the width is o.k.
Again I have to test more systematically. I will also upload some scan 
results together with the debug output to a free webspace provider, I 
will do as soon as possible.

> 
> That's because you're loosing data. They ger lost on their way to 
> the application! It's been explaind a thousand times in the meantime:
> - These old devices have more or less no buffers which are able to 
>   keep data while the driver could not fetch them. Also no backtracking
>   is possible. That's why the driver in general should run in kernelspace,
>   polling the data and refuse the OS from scheduling - what we do not want to.
> 

Sorry, I didn't know that this was diskussed so often. So I can drop the 
idea to use saned for the moment. Well, I can scan as root on the 
command line. With su, chown and bash scripts I can surely bring some 
icons on my user-desktop, that perform scans for some common scenarios.
Hey, this is much more than I could do with Windows XP or Vista.

> Other timing conditions - no way for you to fix that. 

:-(

>>Finally there's still the problem that after one or two hours system
>>uptime the scanner stops working at all. Scanimage -V or -L still
>>works, everything else fails. After shutdown, power off and boot
>>(reboot alone doesn't help) it works again.
> 
> 
> This is quite strange. What's the debug-output like, when this happens?

And I cannot really reproduce it. Yesterday, 2 hours after I thought it 
was "gone" (no scan possible) it worked again without reboot. Today 
morning it was dead again.
The last line in the debug output tells me, that something waits 30s for 
the lamp warming, but there's no progress even after 300s.

> 
> Are you saying Win2K? Are you shure? It thought there ain't any drivers
> available for this OS, because the driver will completely freeze the system
> during scans!

Yes, I do. I got the scanner as a present 4 years ago. The owner could 
not find a driver for an OS newer than NT4.0. Don't ask me what I did 
exactly, I did not write anything down, I was just playing. I installed 
  drivers for other scanners (PRIMAX, UMAX, PLUSTEK) and replaced some 
dll's with the versions taken from the NT-driver of my one. Then, there 
was the moment when it worked and it works until today. AFAIR is it the 
Twain-interface of a "Colorado" model, but I'm not really sure. That's 
why a have a three backups of this installation at three different 
places ;-)

Many thanks for your fast resonse

Daniel