[sane-devel] Intend to write driver(s)

Sat Aug 4 19:27:11 UTC 2007

Hi Leandro,

Sorry for the very late reaction. I do have some information for you
which may help.

Look at the site http://zub.fei.tuke.sk/primax/ of Peter Popovec.
It contains a sane backend for the E3 ASIC, which our scanners have.
The only thing lacking in this backend is that it is for parallel port
scanners and not for USB. Luckily, the chip which does the bridging of
parallel port over USB is well known, it is the GeneSys Logic GL640.
There are many duplicate implementations of this USB bridge already in
the SANE backends, it appears to reside in at least 3 backends:
genesys, canon630u, and u12. So I guess it wouldn't be hard to
implement this in your sane backend. BTW: Does anybody know, Is there
a good reason for implementing this chip this many times?

It seems the modifications are mostly necessary in the port.c file (of
the sane backend of Peter Popovec) to get it working. I guess there
should be a USB version for the following functions.

epp_off();
epp_read();
epp_read_one();
epp_write();
epp_write_one();
switcher_online ();
switcher_offline ();

The first five are not that hard I think, but I do not really have a
clue yet how to do the last two functions.

If we can get USB support working, at least 6 new devices would be
supported. This would be nice. I contacted Peter Popovec, but since he
does not have such a USB scanner he would rather not implemented this
himself.

I guess I answered your first question: we should edit the backend of
Peter Popovec. The second question: I don't know if it is possible to
damage the scanner. The third question: the backend of Peter Popovec
does not seem to have any licencing issues, this in contrast to the
viceo backend.

All the best,
Robert

2007/7/21, Dr. Fiemost <drfiemost at email.it>:
> In data Tue, 19 Jun 2007 09:13:58 +0200, Robert Brijder
> <rbrijder at gmail.com> ha scritto:
>
> > 2007/6/18, drfiemost at email.it <drfiemost at email.it>:
> >> > Hello,
> >> >
> >> > I have the following two scanners.
> >> >
> >> > * Compeye Simplex 1236C,
> >> >   Interface: Parport USB.
> >> >   USB id: 0x05cb/0x1483
> >> > * Primax Colorado USB 19200,
> >> >   Interface: USB,
> >> >   USB id: 0x0461/0x0360
> >> >
> >> > The first one is mentioned on the sane website as unsupported, the
> >> > second one is not mentioned at all. The output of sane-find-scanner -v
> >> > -v with the second scanner connected is show below. My question is,
> >> > which scanner would be most easy to write a driver for (I would guess
> >> > the first one)? I would then try to write a driver for that one first.
> >> >
> >> > BTW: I have never before written a driver, however I can write in C
> >> > and I have read the SANE standard.
> >> >
> >> > Thanks,
> >> > Robert
> >>
> >> Hi Robert,
> >>
> >> I have an LG Electronics Scanworks 600U which is based on the same
> >> chipset
> >> of your Primax Colorado USB 19200 (as reported at
> >> http://viceo.orcon.net.nz/), so if you intend to develop a driver for
> >> that
> >
> > Yes, I noticed that site too, and looked at the source code. It is
> > based on the windows source code. It is probably best to first
> > consider the E3 Driver patch Release 0.1 (which is most close to
> > windows source) instead of the latest 0.6. Version 0.1 is small and
> > easy to read while the versions after 0.1 seems to contains much
> > copy-paste's from other sources. The E3 chip seems to have quite an
> > easy interface, 32 8-bit registers with proper documentation of the
> > bits.
> >
> > I do not have that much spare time, but I'll probably work on it on
> > some weekends. Of course, every help is very good. I think it is best
> > to indeed read first the sane standard, then probably read some
> > (relatively easy) sane-backend for usb-scanners and then read release
> > 0.1 of the E3 driver.
> >
> > All the best,
> > Robert
> >
> >
> >> scanner I'd like to help.
> >> I have some knowledge of C/C++ but no experience with SANE developing.
> >> If you're interested I'll start reading SANE documentation :)
> >>
> >>
> >> Best regards,
> >> Leandro
> >>  --
> >>  Email.it, the professional e-mail, gratis per te: http://www.email.it/f
> >>
>
> Hi Robert,
>
> do you have any news?
> I've read the documents and the source code, so I'd like to start
> experimenting, but I have some questions:
> - is there a backend which could be used as starting point or it is better
> to start from scratch?
> - would it be possible to damage the scanner by sending some wrong
> commands?
> - are there licensing issues in using info desumed from the E3 Driver?
>
> Thank you,
> Leandro
>
>
>  --
>  Email.it, the professional e-mail, gratis per te: http://www.email.it/f
>
>  Sponsor:
>  In REGALO un GIOCO! Scegli GPBikes 3D,Bubble Boom, Rock City Empire
>  Clicca qui: http://adv.email.it/cgi-bin/foclick.cgi?mid=6732&d=21-7
>