If you are seeing disconnects within 3 seconds of connection, then it is most likely an issue with your USB cable/hub. I'd recommend trying with a different cable on an entirely different computer. If you were connecting to a hub, try connecting to the various USB ports on the machine itself.
On Thu, Sep 25, 2014 at 8:22 PM, Ryan Wong <[email protected]> wrote: > I have already followed a long checklist for properly installing the USB > drivers for my Nexus 7 (2013) running Android 4.4.4, on host Windows 7 SP1. > > What I mean is: > > - I am using the Google USB Driver that came with Android SDK Manager, > revision 11. > - I have cycled through all of the USB protocol combinations to make > sure the device drivers are installed: > - PTP only, MTP only, PTP+ADB, MTP+ADB, ADB only > - I have made sure that for each protocol where ADB is enabled, I can > connect to the device via ADB and issue shell commands, list files, etc. > - I have also made sure that if I toggle the USB protocol combinations > (between PTP/MTP), the ADB connection stays alive. > > However, what annoys me is that: > > - The ADB connection will sometimes just drop, for no apparent reason. > - Sometimes this happen when the device is idle; sometimes it happens > in the middle of application testing. > > To reconnect, I toggle through the protocol combinations (between > PTP/MTP). During idle time this is no problem, but when it happens during > application testing, the testing has to be restarted from beginning. > > I would like to get some ideas (or, conspiracy theories) about why this > could possibly happen. > > Note: this is my only test device and workstation I can use for Android > development. > > ADB_TRACE seems to only print the communications between the ADB client > and ADB daemon - it doesn't seem to print out USB communications which I > think is relevant to this issue. > > Just as a hypothesis, I have also tried the "Developer Options - Stay > awake", and on Windows Device Manager - USB Hub - Uncheck "Allow computer > to turn off this device to save power". Disconnection is less frequent but > still occurs. > > (Before I use those two options, the disconnection happens within 3 > seconds of establishing a fresh new ADB connection.) > > -- > You received this message because you are subscribed to the Google Groups > "adt-dev" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "adt-dev" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
