[sane-devel] Trouble with Primax 4800 Direct

[Gerhard Jaeger]

Hi,

On Monday 24 October 2005 12:35, Daniel Klär wrote:
> 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.

Okay - please keep me informed.

>   >
> > 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.

Now I understand. This has been fixed a few weeks ago - please use the
latest CVS snapshot for further testing.

> > 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.

Well you only need access to the parport device @ /dev/parport0 and then
you should be able to use the scanner as "normal" user.

> > 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.

This looks like the timing variable overflow and has also been fixed a couple
of weeks ago.

> > 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 ;-)

Oh,oh, but congrats to make it work that way ;)

Ciao,
Gerhard