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Re: USB device not accepting new address



For information, I have the same behaviour with an USB 1.1 hub.
I'll check voltage, etc...

Thanks


Orjan Friberg wrote:

>
> Slightly alarming; some control traffic may have been lost as the error
> message basically indicates that we're removing DMA descriptors for an
> active endpoint.
>
> > Don't you think a USB 2.0 device is totaly compliant with the previous
> > specifications ?
>
> The device should be compliant; it's just that I don't know what happens
> electrically on the bus when it switches to/from high speed/full
> speed/low speed and how the HC handles it.
>
> > Are the control frames electrically differents from the other ones ?
>
> I don't think so.
>
> > Can it be due to the PCB design of the USB transceiver ?
>
> Could be.  The cases I've seen where device numbering fails were due to
> hardware issues.  But since things seem to work reasonably when you plug
> the HID device directly into the board's USB port, and just not when
> there's a hub in between, I don't know (it could be related to the speed
> mode switch).  I'd suggest checking voltage levels etc.  That could very
> well be the reason for the device not answering the device numbering
> request.
>
> --
> Orjan Friberg
> Axis Communications