[sane-devel] backend in progress: canon i-sensys mf4570dn, 'mfnp' protocol

[Louis Lagendijk]

On Thu, 2011-02-24 at 03:44 +0100, chrysn wrote:

> 
> so my questions to the list are:
> 
> * what is the background of the existing bjnp code, and how extensible
>   is it?
> 
There is no public documentation of the protocol that I am aware of. I
had to reverse engineer the windows packer trace to come up with what I
have now. Everything works except for the scan buttons. I have not had
the time or interest to dig further into that area for a long time.
Please note that this code only provides the USB over IP stack and is
used by the pixma_mp150 backend and possibly others. The actual backend
sends the usual usb commands that get routed over IP.  
Is there a backend that supports your device? If so, I could have a look
at some packet traces to see if support for your devices IP-protocol is
doable.

>   (this question probably goes to louis lagendijk (judging from the
>   copyright notes), and the answer will partially depend on the
>   differences between the protocol variants in use, which i hope to be
>   able to judge better once i understand what the current code does.)
> 
> * are there other (similar, i-sensys or other mf) devices in reach of
>   list readers, which could help me to understand more of the protocol
>   and test the implementation?
> 
I developed the code using an MP970 that died. I am now using an MP980.
But the code works on a lot of devices using an ethernet or even
wireless connection. Again, does the device work over USB?
 
> * is there a way to have an out-of-process backend in sane? (i could
>   provide that easily with the current python implementation, and
>   messing around with signals for udp timeouts feels much more
>   comfortable when i'm in my own process)
> 
Not that I know of. Does python allow for an easy wrapping of
C-libraries?

kind regards, Louis