To resolve this issue, you can use one of the following methods.
Note After you apply this update, you can perform kernel debugging on Intel® Atom™ Processor Z373x and CHT-CR devices by plugging a USB 3.0 cable into the external USB 2.0 port. This feature is also supported on full Intel® Atom™ Processor Z374x, Z377x, Z378x, Z379x or N28xx/N29xx and CHT devices when plugging a USB 2.0 cable into the external USB 3.0 port, because the external USB 3.0 port is backward-compatible with USB 2.0.
Method 1: Windows Update
This update is available from
Windows Update.
Method 2: Update Rollup
To resolve this issue, install the
November 2014 update rollup for Windows RT 8.1, Windows 8.1, or Windows Server 2012 R2.
Prerequisites for hardware settings
To apply this update, you have to meet the following conditions:
- The firmware should have the Extensible Device Controller Interface (xDCI) Debug Port Table 2 (DBG2) entry.
- The xDCI controller is exposed correctly to the desired USB debug port.
- The OEM firmware has to hide the xDCI controller in PCI, or expose it as an ACPI device instead of as a PCI device.
Note The base address for xDCI will be pointed to by the DBG2 table entry.
- The USB cable should be plugged in before the platform starts.
After you apply this update
The following scenarios are not supported:
- There is no support for Power Management. This is the same as the Extensible Host Controller Interface (xHCI) debug solution currently available.
- There is no support for hot-plug scenarios.
- There is no support for USB-reconnection scenarios.
Additionally, after you apply this update, a polling mechanism is added to achieve and process events from the Event buffer. Because a polling mechanism is used, the rate of polling is faster than the rate of hardware events to fill the Event buffer.