VideoPortStartTimer function

The VideoPortStartTimer function enables calls to a miniport driver's HwVidTimer function.

Syntax

VIDEOPORT_API VOID VideoPortStartTimer(
  PVOID HwDeviceExtension
);

Parameters

HwDeviceExtension

Pointer to the miniport driver's device extension. This pointer is the input parameter to the HwVidTimer function.

Return Value

None

Remarks

After a miniport driver calls VideoPortStartTimer, its HwVidTimer function is called at approximately one-second intervals until the miniport driver calls VideoPortStopTimer. A miniport driver's HwVidTimer function must not call VideoPortStopTimer.

A miniport driver cannot call VideoPortStartTimer or VideoPortStopTimer if its DriverEntry function set the HwTimer member of the VIDEO_HW_INITIALIZATION_DATA structure to NULL.

Requirements

   
Minimum supported client Available in Windows 2000 and later versions of the Windows operating systems.
Target Platform Desktop
Header video.h (include Video.h)
Library Videoprt.lib
DLL Videoprt.sys
IRQL <=DISPATCH_LEVEL

See Also

DriverEntry of Video Miniport Driver

HwVidTimer

VIDEO_HW_INITIALIZATION_DATA

VideoPortStopTimer