Alexander Feldman wrote: > I could not find a backend for my PrimeFilm 1800i, so I decided to write > one. It seems that I can't get anything about the protocol so I used > usbsnoop on a windows box to log the protocol. It produced a nice 8 Mb log > file. Next, lacking any experience with USB I started reading the specs, the > Linux USB programming manual some other USB backends and more. > As it is a complete mess in my head now, I would ask here for a hint - what > to do next - for the last few hours I was trying to manually send some URBs > using a utility USB-robot, but to no avail.
Can you post a link to the log? Good things to log are repeated scans where each time only 1 scan attribute is changed (resolution, scan position etc.) Can you see some regularity in the logs? Like repeating groups of USB transfers? If you see a transfer once a second, this could be some kind of poll for button status for example. It also helps to document everything you find out and put it on a simple webpage. This way other people with the same idea of writing a backend can combine forces with you and don't have to start from scratch. Kind regards, Bertrik
