VideoDebugPrint macro

The VideoDebugPrint macro prints the specified debug message to the kernel debugger.

Syntax

VOID VideoDebugPrint(
  [in] ULONG DebugPrintLevel,
  [in] PCHAR DebugMessage,
       ...   
);

Parameters

• DebugPrintLevel [in]
  Specifies the level of debug messages to be printed. This parameter can be set to one of the following enumerators.

  Enumerator	Value
  Error	0
  Warn	1
  Trace	2
  Info	3

   

  In a checked build, set this parameter to Error to ensure that the specified debug message is printed. Otherwise, if the DebugPrintLevel parameter is set to any of the other three values, a debug message is printed only if the global debugging level in the registry is greater than or equal to that value. See the Remarks section for more information.

• DebugMessage [in]
  Pointer to a string containing the debug message to be printed. In addition to text that is displayed in the debugger, this string can contain printf-style format specifiers, one for each value following the string in the call to this macro.

• **

Return value

None

Remarks

The video port driver checks the adapter key in the registry for the VideoDebugLevel entry at startup. The video port driver also has a global variable with the same name. If the VideoDebugLevel entry does not exist in the registry, the video port driver uses a default value of 0.

The global debugging level can be changed in the registry or in the debugger at run time:

1. Change the value of the VideoDebugLevel registry entry. The new value will take effect on the next boot.

2. Change the video port driver's VideoDebugLevel global variable in the debugger at run time. The new value takes effect immediately.

The compiler eliminates references to VideoDebugPrint for free builds of the video port driver and video miniport drivers.

Requirements

See also

VideoPortLogError

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