FIX: Incorrect 1394 Node Becomes Cycle Master

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After you start your computer, although some conferencing cameras enumerate correctly and appear in Device Manager with no errors, they do not stream video.
With certain 1394 topologies at startup time, the 1394 host controller driver (1394Bus.sys/OHCI1394.sys) incorrectly chooses the wrong 1394 node as the Cycle Master. This results in no start cycle packets and, therefore, no isochronous streaming.


To work around this problem so that the camera correctly streams video, follow these steps:
  1. Unplug the conferencing camera.
  2. Plug the camera in again.
  3. Restart the program; this causes a bus reset and solves the problem.
A supported hotfix is available from Microsoft. However, this hotfix is intended to correct only the problem that is described in this article. Apply this hotfix only to systems that are experiencing this specific problem. This hotfix might receive additional testing. Therefore, if you are not severely affected by this problem, we recommend that you wait for the next software update that contains this hotfix.

If the hotfix is available for download, there is a "Hotfix download available" section at the top of this Knowledge Base article. If this section does not appear, contact Microsoft Customer Service and Support to obtain the hotfix.

Note If additional issues occur or if any troubleshooting is required, you might have to create a separate service request. The usual support costs will apply to additional support questions and issues that do not qualify for this specific hotfix. For a complete list of Microsoft Customer Service and Support telephone numbers or to create a separate service request, visit the following Microsoft Web site: Note The "Hotfix download available" form displays the languages for which the hotfix is available. If you do not see your language, it is because a hotfix is not available for that language.

File information

The English version of this fix has the file attributes (or later) that are listed in the following table. The dates and times for these files are listed in coordinated universal time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the Time Zone tab in the Date and Time tool in Control Panel.
Date         Time   Version        Size    File name     Operating system-------------------------------------------------------------------------15-AUG-2002  09:31  5.1.2600.54    49,792  1394BUS.SYS  Windows XP					
Microsoft has confirmed that this is a bug in the Microsoft products that are listed at the beginning of this article.
Note This is a "FAST PUBLISH" article created directly from within the Microsoft support organization. The information contained herein is provided as-is in response to emerging issues. As a result of the speed in making it available, the materials may include typographical errors and may be revised at any time without notice. See Terms of Use for other considerations.

Article ID: 326464 - Last Review: 01/11/2015 22:03:22 - Revision: 1.0

Microsoft Windows XP Professional

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