INT 10 - Cirrus Logic BIOS - GET USER OPTIONS
        AH = 12h
        BL = 9Ah
Return: AX = options word 1 (see below)
        CX = options word 2 (see below)
SeeAlso: AH=12h/BL=80h,AH=12h/BL=84h,AH=12h/BL=93h,AH=12h/BL=A0h
SeeAlso: AH=12h/BL=A3h,AH=12h/BL=A4h

Bitfields for options word 1:
 bits 0,1 reserved
 bits 2-4 monitor type
 bits 5-6 maximum vertical resolution
 bits 7-9 reserved
 bit 10 force 8-bit operation
 bits 11-13 reserved
 bit 14 vertical refresh frequency at 640x480
 bit 15 reserved

Bitfields for options word 2:
 bits 0-3 reserved
 bits 4-5 vertical refresh frequency at 1280x1024
 bits 6-10 reserved
 bits 11-12 vertical refresh frequency at 800x600
 bits 13-15 vertical refresh frequency at 1024x768

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