Bitfields for Cirrus Logic options word 1:
Bit(s)	Description	)
 0,1	reserved
 2-4	monitor type
 5-6	maximum vertical resolution
 7-9	reserved
 10	force 8-bit operation
 11-13	reserved
 14	vertical refresh frequency at 640x480
	=0 60 Hz
	=1 high refresh
 15	reserved
SeeAlso: AH=12h/BL=AEh