[sane-devel] reverse engineering / usbsnoop

Mbosowo I Sampson msampson@ic.sunysb.edu
Sat, 11 Sep 2004 03:34:14 -0400 (EDT)

After reading reams of documentation, I think I have a grasp on how the 
USB protocol works. I started snooping the usb traffic of my hp scanjet 
3970 so I can start writing the backend for it. I have a couple of 

With Snoopy Pro it seems to stop logging information once the actual scan 
begins. Someone else posted something on SF page about it stopping once 
the bulk transfer began. I was wondering if anyone knew how to get around 
this. I tried sniffit, but the documentation says it only works for NT 

I was looking at a usb dump,

posted by this guy,

On this page he says that the chipset he was looking at had 244 registers. 
How exactly can you tell that by the logs?

I'm looking at the logs, and I'm not sure where to start. I was to start 
simple by writing a stand alone application that tuns on the lamp, then 
build on it from there. I have a session log, but I have no idea how to 
find out what register and values are needed to turn on the lamp. Any 

I wanted to post the Snoopypro log here, but apprently its a binary file. 
I tried to use usb-robot to control the scanner from linux, its not 
working, and there doesn't seem to be any documentation on usb-robot 
anywhere. lovely.

I'm not completely sure what I'm asking. It all seems a little murky at 
the moment.