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UsbBuildFeatureRequest macro

The UsbBuildFeatureRequest macro formats an URB with the parameters necessary to request that a feature be turned on or off on a USB device.

Syntax

void UsbBuildFeatureRequest(
  [in, out] PURB   Urb,
  [in]      USHORT Op,
  [in]      USHORT FeatureSelector,
  [in]      USHORT Index,
  [in]      PURB   Link
);

Parameters

  • Urb [in, out]
    Pointer to an URB to be formatted as a feature request to a device.

  • Op [in]
    Specifies one of the following operation codes:

    • URB_FUNCTION_SET_FEATURE_TO_DEVICE
      Sets a USB-defined feature, specified by FeatureSelector, on a device.

    • URB_FUNCTION_SET_FEATURE_TO_INTERFACE
      Sets a USB-defined feature, specified by FeatureSelector, on an interface for a device.

    • URB_FUNCTION_SET_FEATURE_TO_ENDPOINT
      Sets a USB-defined feature, specified by FeatureSelector, on an endpoint for an interface on a USB device.

    • URB_FUNCTION_SET_FEATURE_TO_OTHER
      Sets a USB-defined feature, specified by FeatureSelector, on a device-defined target on a USB device.

    • URB_FUNCTION_CLEAR_FEATURE_TO_DEVICE
      Clears a USB-defined feature, specified by FeatureSelector, on a device.

    • URB_FUNCTION_CLEAR_FEATURE_TO_INTERFACE
      Clears a USB-defined feature, specified by FeatureSelector, on an interface for a device.

    • URB_FUNCTION_CLEAR_FEATURE_TO_ENDPOINT
      Clears a USB-defined feature, specified by FeatureSelector, on an endpoint, for an interface, on a USB device.

    • URB_FUNCTION_CLEAR_FEATURE_TO_OTHER
      Clears a USB-defined feature, specified by FeatureSelector, on a device-defined target on a USB device.

  • FeatureSelector [in]
    Specifies the USB-defined feature code that should be set or cleared on the target as specified by Op.

  • Index [in]
    For a feature request for an endpoint or interface, specifies the index of the endpoint or interface within the configuration descriptor. For the device, this must be zero.

  • Link [in]
    Reserved. Must be set to NULL.

Return value

This macro does not return a value.

Requirements

Target platform

Desktop

Header

Usbdlib.h (include Usbdlib.h)

See also

URB

_URB_CONTROL_FEATURE_REQUEST

USB device driver programming reference

 

 

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