INT 67,41 - Get Page Frame Base Address (LIM EMS 3.0+)

	AH = 41h


	on return:
	AH = 00 success
	   = error code (see EMS STATUS)
	BX = segment of page frame (PFBA)


	- use this to determine where in the 1Mb memory address the page
	  frame will be mapped
	- registers not listed are preserved