Dnia poniedziałek, 3 września 2012 o 22:00:03 Alan Stern napisał(a): > On Mon, 3 Sep 2012, Marek Floriańczyk wrote: > > HI, > > > > Debian testing, kernel 3.2.0-3 and results are the same. Order in which I > > call devices is important, first device I call always gives reply, > > second one almost never, no matter on what bus number they are. When I > > insert some delay between commands (500 ms) everything works fine - i > > got reply from both devices, always. > > Unfortunately I don't have usb tester, but maybe I will try to do test > > app on windows, so I will get some confirmation. > > This is puzzling. Since the devices are on different buses, they > should be totally independent, right? Unless they can communicate over > some other medium (not USB). > > Can you try running the program on a different computer, to help rule > out USB hardware problems on the motherboard? I did this today, I installed new system on different machine to test new kernel, and they behave identically. But you know, devices are communicating with remote actuators by radio frequency, and remote actuators are sending status by radiograms. I was told that devices have some system to distinguish between commands that are directed to them or to other device, but there is always a chance that radiograms somehow interfere with each other. I can always write to manufacturer of this devices and ask for confirmation, and I probably will. regards. Marek > > Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
