Re: [libusb] Endpoint 0x81 Not Responding

[Phani K. <pha...@gm...>]

Thanks Tim.

In 9.1.1.5 section of  USB 2.0 Specification, it is mentioned as below:

9.1.1.5 Configured
Before a USB device’s function may be used, the device must be configured.
>From the device’s
perspective, configuration involves correctly processing a
SetConfiguration() request with a non-zero
configuration value. Configuring a device or changing an alternate setting
causes all of the status and
configuration values associated with endpoints in the affected interfaces
to be set to their default values.
*This includes setting the data toggle of any endpoint using data toggles
to the value DATA0*.

Can you please tell me what is the meaning of "

*This includes setting the data toggle of any endpoint using data toggles
to the value DATA0"?*

*Regards*

*Phani*



On Fri, Mar 25, 2016 at 8:36 PM, Alan Stern <st...@ro...>
wrote:

> On Fri, 25 Mar 2016, Phani Kumar wrote:
>
> > Thanks Alan.
> >
> > The code is working now and I am not resetting the toggle at all.
> >
> > 1. I assume I have to reset the toggle only when an endpoint halts for
> this
> > device?
>
> That's true for all devices, not just yours.
>
> > 2. Usually in our code, we send reset toggle (by clearing halt feature)
> on
> > every pipe initialize. All other devices work with this code. However
> this
> > device is vendor defined and it is not accepting this behavior. How can I
> > differentiate this behavior only for this device and how windows works in
> > the same scenario? Any idea?
>
> You should never do a Clear-Halt unless you _know_ the endpoint is
> halted.  For any device.
>
> In most cases it won't hurt, but some devices don't handle it
> correctly.
>
> Alan Stern
>
>