INT 10 - VIDEO - UltraVision - GET STATUS (INSTALLATION CHECK)
        AX = CC00h
        SI = 0000h (if checking version)
Return: CX = ABCDh
        AL = Ultravision extensions
            00h enabled
            FFh disabled
        AH = card designator
        BX:00F0h -> palette values (for compatibility with NEWFONT)
        DX = support for high resolution modes
            00h not active
            01h active
        SI = UltraVision version number (v1.2+), high byte=major,low byte=minor
           = unchanged for versions <1.2
SeeAlso: AX=CC02h