Bitfields for EMS frame type:
Bit(s)	Description	)
 0	EMS frame
 1	(if EMS frame) in standard 64K page frame
 2	first 4K of frame is UMB
 3	second 4K of frame is UMB
 4	third 4K of frame is UMB
 5	last 4K of frame is UMB