[sane-devel] Hints for Epson Perfection 1650?

[Roberto Mello]

On Wed, Feb 27, 2002 at 06:02:47PM -0500, Karl Heinz Kremer wrote:
> Actually specifying the read_timeout is the only way to change this
> (that is if you don't want to mess around in the source code): The

Right.

> #define is ignored for EPSON scanners, because at one point we
> thought that 40 seconds would be enough, and 10 seconds for the
> other scanners, so when the driver detects the EPSON vendor ID, 
> it sets the timeout to 40 seconds - if you don't override this
> with read_timeout. 

Ah, didn't know that.
 
> 60 seconds should be enough for the 1650, at least I've never
> heard of any larger timeout required.

Okay.
 
> If the 160 seconds is not sufficient for you, then there is
> something else wrong. It can be so trivial as a faulty cable,
> but can as well be some weird interaction between your scanner,
> the USB interface and the driver version. It's very unlikely that
> it's the backend - as long as you are using the most recent 
> version - at least it works for pretty much everybody else with
> this scanner. 

I don't think the problem is at the backend. The backend seems to be just
fine. It looks like it's something in scanner.c or in the usbcore (or it
could be in the usb-uhci).

The behavior I see is this:

- I scan a couple pictures, all just fine
- Try to scan another one and I get this:

Feb 27 16:54:32 brasileiro kernel: [c6aa90c0] link (06aa9092) element (07fec000)
Feb 27 16:54:32 brasileiro kernel:   0: [c7fec000] link (00000001) e3 IOC Stalled Babble Length=5 MaxLen=5 DT1 EndPt=2 Dev=2, PID=69(IN) (buf=0ed68000)
Feb 27 16:54:32 brasileiro kernel: 
Feb 27 16:54:32 brasileiro kernel: scanner.c: read_scanner(0): funky result:-75. Consult Documentation/usb/scanner.txt.

- At this point xsane says: "Error during read: Invalid Argument"
- The scanner button goes dark and doesn't get lit again.
- The only thing I can do to get back to scanning is to turn the scanner 
  off then back on, or 'rmmod uhci; modprobe uhci', or a combination of
  both.
- At that point the scanner button lights again.

I dont understand all the particulars here, much less of how the usb and
uhci drivers are supposed to work. I'm just throwing data up so that
somebody with a better understanding will hopefully pick it up and be able
to explain.

But this is what I have found that "solves" the problem, at least 
temporarily. 

It's interesting to notice that I couldn't get _anything_ scanned with
xscanimage, and iscan (the japanese app) doesn't seem to work either. It
says it can't send command to the scanner. 

What have other Perfection 1650 users reported? Any of them in the list
with th same problems? Perhaps I did something else wrong? I'd love to
hear reports from other 1650 users, especially if they're using the uhci
driver (for the kernel).

Thanks,

-Roberto

-- 
+----| http://fslc.usu.edu/ USU Free Software & GNU/Linux Club |------+
  Roberto Mello - Computer Science, USU - http://www.brasileiro.net/ 
       http://www.sdl.usu.edu/ - Space Dynamics Lab, Developer    
Please just ignore this tagline, OK?