Mailing Lists: Apple Mailing Lists
Image of Mac OS face in stamp
USB Video Class device problem. Fernando Urbina?
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

USB Video Class device problem. Fernando Urbina?



I have built a USB Video Class web camera, and it runs fine on Windows. On the Mac, it runs fine, but it has a strange problem. When the application using the camera is quit, and then restarted, the application is unable to find the camera. In fact, no application can find the camera. The problem persists until the camera is unplugged physically from the machine, and then plugged in again.

I have looked at the USB traffic with a CATC analyzer, and here is what I see:

Bulk data is streaming along fine
SET_INTERFACE alt setting 0, interface 1. This command is ack'd
Then for a long time I get hammered with IN requests on Endpoint 0. I'm not sure why.
Then a DATA1 is sent from my device, with a zero length data packet. this is acked by the host.
Then there is a CHIRP J
FULL speed J
Full speed k
and a bunch of Chirp J's
Then a get descriptor request



I'm obviously not handling some command right, but I'm not sure what.

I'm hoping that Fernando Urbina will take a look at this.

Thanks


_______________________________________________ Do not post admin requests to the list. They will be ignored. Usb mailing list (email@hidden) Help/Unsubscribe/Update your Subscription: This email sent to email@hidden


Visit the Apple Store online or at retail locations.
1-800-MY-APPLE

Contact Apple | Terms of Use | Privacy Policy

Copyright © 2011 Apple Inc. All rights reserved.