Function 0Fh	Return Current Video State - mode and size of the screen
entry   AH      0Fh 
return  AH      number of character columns on screen 
	AL      mode currently set (see AH=00h for display mode codes) 
	BH      current active display page 
note    If mode was set with bit 7 set ("no blanking"), the returned mode will 
	also have bit 7 set 
 
Sample Code:
\Asm\Lib\BIOS.INC -@BIOSVidModeGet	  MACRO