[sane-devel] reverse engineering advice.
gerard klaver
gerard@gkall.hobby.nl
Mon, 24 Jan 2005 22:50:42 +0100
On Mon, 2005-01-24 at 13:59 -0500, Mbosowo I Sampson wrote:
> I'm in the process of sifting through USBSnoop generated logs for the HP
> 3970, trying to decipher what's going on. I've hit a little bit of
> a wall. Reading the code for the hp5400 driver along with the USBSnoop
> logs posted at http://home.kabelfoon.nl/~bertrik/plugin_hp5470c.log
> has really helped a lot. I would like to start writing my driver but I
> need some advice.
>
> This is the log generated from my scanner after its plugged in:
> http://www.ic.sunysb.edu/Stu/msampson/usbsnoop_pluggedin2.log
>
> The first 4 URB transfers are easy, querying the device, choosing a
> configuration, etc... But after that it gets a little murky. I'm
> looking at the packets going down, and coming up, and I just have no way
> to telling what's doing what. I wanted to use usb-robot to send commands
> one at a time, but the program segfaults on my machine (debian sarge
> 2.6.10)
>
> I have the USB1.1 spec handy, so I understand the structure of the
> packets, but how do you discern what the packets are doing? For example,
> Which of those packets turns on the lamp? Which ones controls the stepper
> motors? Should I just start from the top of the log and send the commands
> myself to see what happens? I'm really itching to get this thing working.
>
> I would love to disassemble the windows driver, but I have no experience
> doing this. I was hoping to tap the collective experience of the group
> before I tried that.
>
> Any help would be much appreciated.
>
> Mboso
>
Have you thought about to try to join the rt88xx backend people.
There will be differences between the scanner chips but maybe
not so great.
http://hp44x0backend.sourceforge.net/
If you compare some usb-sniff output some parts can be the same?
--
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m.vr.gr.
Gerard Klaver