Hi everyone, I have two identical devices on usb (they are connected to bus 5 and bus 3 and they have different serial numbers of course). Devices are CKOZ-00/03 - Xcomfort gateway for controling house electric system. Both of them work fine when connected together and when I'm sending commands to them one by one. Problem appears when I send two commands (one after another in loop) to both devices, which in turn are sending data to remote actuator which in turn should reply with some data. In short words it looks like my computer is loosing one reply from remote device. To give you picture of the problem, situation is like this: There are two jalousie actuator each of them assigned to different CKOZ gateway, and I'm sending them simulatanously command to close jalousie window, both CKOZ gateway are responding OK, and both jalousie are starting to close down, but I got report from only one of the jalousie actuator that it started to work. Sorry for long winded introduction. I have Linux Debian 2.6.32-5-686 #1 SMP and I'm using libusb-1.0-0 2:1.0.8-2 At the beginning I thought that it is some problem with my code or library, but when I'm using usbmon to sniff USB packets it actually shows that data I'm waiting for, from jalousie actuator (data that says it started to work), never come to me. I'm sniffing usb packets like this: mount -t debugfs none_debugs /sys/kernel/debug modprobe usbmon for device on bus5 cat /sys/kernel/debug/usb/usbmon/5t for device on bus3 cat /sys/kernel/debug/usb/usbmon/3t debug from bus5: f3d2a580 3145568713 S Io:002:02 -115 9 = 09b10d0e ... f3d2a580 3145588922 C Io:002:02 0 9 > f3e62500 3145876935 C Ii:002:01 0 19 = 08c31c04 ..... e5a19a00 3145877027 S Ii:002:01 -115 19 < e5a19a00 3146292920 C Ii:002:01 0 19 = 0dc10470 ..... e5a19a00 3146292994 S Ii:002:01 -115 19 < e5a19a00 3151294925 C Ii:002:01 -2 0 f3a80b00 3151295016 S Ii:002:01 -115 19 < f3a80b00 3156296909 C Ii:002:01 -2 0 debug from bus3: f3e62480 3145288417 S Ii:002:01 -115 19 < f3d2a600 3145589489 S Io:002:02 -115 9 = 09b11e0e ..... f3d2a600 3145610306 C Io:002:02 0 9 > f3e62480 3146154325 C Ii:002:01 0 19 = 08c31c04 ...... e5a19500 3146154405 S Ii:002:01 -115 19 < e5a19500 3151156340 C Ii:002:01 -2 0 f3a80b80 3151156455 S Ii:002:01 -115 19 < f3a80b80 3156158326 C Ii:002:01 -2 0 So proper data are on bus 5: 09b1.... - sending command to device 08c3.... - CKOZ gateway respond that it transmited data to remote actuator 0dc1.... - remote actuator respond that it started to work On bus 3 there is no response from remote actuator. So my questions are: When I'm sniffing data like this, is it still possible that kernel, or module, or whatever is loosing data that I'm waiting for, and If so, how can I produce more detailed debug. Or is it actually a proof that CKOZ devices connected to my computer are not getting data from remote actuator in the first place? best regards Marek -- 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