I posted this question in Stack Overflow, and somebody recommended that I post it here. I'm using an IMU (Inertial Measurement Unit) which connects via USB. I have to unplug it and plug it again to be able to use it. The IMU is used to get acceleration and positioning data (among other things). I have an example driver code from the manufacturer (I'll call it driver A), and another driver I found on github (driver B). Both have the same problem. If I plug in the device everything works. If the computer starts, and the IMU is already plugged in, I have to unplug it and plug it again. This is unacceptable because the IMU will be used in a robot, so we cannot just unplug it every time the robot starts. With driver A I get some basic information from the device like model number, but it freezes when I request data. With driver B, it just won't even start. Until, like I said, I unplug it and plug it again and then everything works. I found this code to "reset" a usb device via the OS (I'm using linux, ubuntu 14.04). When I run it dmesg gives the following output: [ 2443.165898] usb 3-1: reset full-speed USB device number 2 using xhci_hcd [ 2443.182281] xhci_hcd 0000:00:14.0: xHCI xhci_drop_endpoint called with disabled ep ffff880036bed700 [ 2443.182290] xhci_hcd 0000:00:14.0: xHCI xhci_drop_endpoint called with disabled ep ffff880036bed740 [ 2443.182295] xhci_hcd 0000:00:14.0: xHCI xhci_drop_endpoint called with disabled ep ffff88003687e600 [ 2443.182310] usb 3-1: ep 0x82 - rounding interval to 1024 microframes, ep desc says 2040 microframes [ 2443.182695] cdc_acm 3-1:1.0: This device cannot do calls on its own. It is not a modem. [ 2443.182725] cdc_acm 3-1:1.0: ttyACM0: USB ACM device If I run lsusb, the IMU is shown. But the IMU is still not working. The blinking of the led on its cover says its in idle mode as it was before. I still have to manually unplug it and plug it again for it to work. Maybe is a power issue? Has anyone reading this have had issues like this before? This data is to be published using ROS if that is of any help. The device is a microstrain 3DM-GX4-25 IMU. EDIT: When I say I have two drivers, what I mean is that I have two programs that can read data from the device. They may not necessarily be in a "driver format". I'm going over this right now. Jose Colmenares. Software Engineer. Dynamic Legged Systems, Advanced Robotics. Italian Institute of Technology. +39 010 717 818 18-- 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
