INT 62 u - FGDRIVER v4.02 - "FG_GETADDR" - GET SEGMENT OF ACTIVE VIDEO PAGE
	AX = 0039h
Return: AX = segment of active video page
Note:	the FGDRIVER functions are rearranged with each major release, but
	  their parameters do not change (see #03474 at AX=0000h)
SeeAlso: AX=0042h,AX=00ACh