On Wednesday 14 February 2007 11:51 pm, Andrew Morton wrote: > I am having troubles connecting and interfacing to a device called a > USRP via USB which is used with GNU Radio. At one time, the setup > worked perfectly fine with no errors. Then i tried to give a regular > user permission to the USB device and everything went downhill. > > Now, whenever I plugin the device sometimes I sometimes get the error: > usb 1-7: device descriptor read/all, error -71
This is a known problem nobody quite has a handle on. At some point in the past, the enumeration sequence started failing in that way, for certain devices (but not all of them) on certain hosts (ditto). Naturally the developers didn't have such devices, and don't see such problems themselves. My suspicion is that this is mostly a timing issue, but those errors show up at a sensitive point in the device discovery sequence where errors in device firmware -- and potentially hardware -- also have a bad habit of showing up. (It's the old "works with <version X of> Windows, so we'red done testing" mindset.) So, painful though it is, my main suggestion is "git bisect". With luck that will turn up a USB patch with an un-anticpated side effect. - Dave ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys-and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ linux-usb-devel@lists.sourceforge.net To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
