Sorry I did a simple reply :( I am going to try that, as well as I understood it :) else I'll ask you more questions... Thank a lot for your help, Thibault
Henning Meier-Geinitz wrote: >Hi, > >On Mon, Apr 12, 2004 at 05:08:27PM +0200, Thibault North wrote: > > >>ok let's go for a test. But I'am beginning, don't go to quickly :) >> >> > >Ok. First: reply to the sane-devel mailing list, not to me personally :-) > > > >>You are talking of check-usb-chip.c in sane-backend 1.4pre tools directory ? >> >> > >Yes. It's part of sane-find-scanner. It's used by sane-find-scanner to >find out which kind of USB chip is used. The code tries one chip after >the other. It first tests for the characteristics of the USB device >descriptor and interface descriptors (e.g. USB version, number of >endpoints). If it finds out that the current USB version is 1.1 but >the vhipset has usually 2.0 it's not that chip so the next test is >executed. If all the descriptor characteristics are found to be met, a >short command is sent to the scanner, e.g. to write to a register and >read that value from it again. If that's also ok, the chip is detected >for sure. > > > >>What do I have to do with it ? how to add a test ? >> >> > >Read the source code. You'll see tests for different chipsets. At the >end of the code, all the different tests are executed one after the >other. Add one test as mentioned in my previous mail. > >Check at which test it fails and have a look at the output of >sane-find-scanner -v -v. That output contains all the fields the USB >provides. > > > >>Maybe I should read the documentation first... I'll print it now, >>perhaps I'll undestand it :) >> >> > >Have a look at the USB specification. It explains what all these >descriptors are and what the balues mean. > > > >>Programming: i didn't go far, but I will be pleased to learn more... (I >>did a little of C++, but I don't know C structures at all...) >> >> > >You'll learn to use them. But in this case, you can just copy the >already existing tests and change the values. > >Bye, > Henning > > >
