WinUsb_GetCurrentFrameNumber routine

The WinUsb_GetCurrentFrameNumber function gets the current frame number for the bus.

Syntax


BOOL __stdcall WinUsb_GetCurrentFrameNumber(
  _In_  HANDLE         DeviceHandle,
  _Out_ PULONG         CurrentFrameNumber,
  _Out_ LARGE_INTEGER  *TimeStamp
);

Parameters

DeviceHandle [in]

The handle to the device that CreateFile returned.

CurrentFrameNumber [out]

The current frame number value.

TimeStamp [out]

The time stamp value when the current frame was read.

Return value

WinUsb_GetCurrentFrameNumber returns TRUE if the operation succeeds. Otherwise this function returns FALSE, and the caller can retrieve the logged error by calling GetLastError.

Remarks

The caller may compare the PerformanceCount with the value returned by the Win32 function QueryPerformanceCounter to determine if there has been a delay in transitioning back to user-mode after the frame number was read. The caller can then adjust the starting frame number as needed.

Requirements

Minimum supported client

Windows 8.1

Minimum supported server

Windows Server 2012 R2

Target platform

Universal

Header

Winusb.h (include Winusb.h)

Library

Winusb.lib

DLL

Winusb.dll

See also

WinUSB Functions
Send USB isochronous transfers from a WinUSB desktop app

 

 

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