#26 SynchFrame to Isochronous endpoint throws UsbException


When I do a StandardRequest.synchFrame() with a valid
UsbDevice and a valid Isochronous endpoint, instead of
getting a data event, I get a UsbException with the
error number -121 (which should be a
UsbShortPacketException based on a previous defect)

The endpoint address is 0x88, and the endpoint is on
the active Configuration, Interface & Alternate Setting.


  • Dan Streetman

    Dan Streetman - 2004-05-24
    • assigned_to: nobody --> ddstreet
  • Dan Streetman

    Dan Streetman - 2004-05-26

    Logged In: YES

    The -121 bug is fixed in CVS, so a UsbShortPacketException should be
    generated now instead of a UsbException with error -121. Need to do a
    bus trace to figure out if the device (or Linux USB stack) is actually causing
    the UsbShortPacketException or if there is actually a javax.usb bug.

  • Dan Streetman

    Dan Streetman - 2004-06-08
    • status: open --> closed-invalid
  • Dan Streetman

    Dan Streetman - 2004-06-08

    Logged In: YES

    Bus tracing showed that the device is actually rejecting the request.
    According to the USB spec, "If the specified endpoint does not support
    this request, then the device will respond with a Request Error". So it looks
    like the device has not been programmed to support the request, and there
    is no bug in javax.usb


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