Format of EMS frame status record:
Offset	Size	Description	)
 00h	BYTE	frame type (see #01517)
 01h	BYTE	owner handle (00h/FFh = none) from frame including UMB
		index to UMB frame descriptors
 02h	WORD	logical page for frame, 7FFFh if none, FFFFh if non-EMS frame
 04h	BYTE	EMS physical page number (FFh for non-EMS = don't care???)
 05h	BYTE	flags for non-EMS frames (00h for EMS frame)
		bits 0,1 for first 4K, bits 2,3 for second 4K, etc:
		  10: direct mapping (linear address = physical address)
		  01: UMB mapping