INT 10 - Cirrus Logic BIOS - INQUIRE VGA TYPE
        AH = 12h
        BL = 80h
Return: AX = controller type in bits 13-0 (see below)
            bit 14: ???
            bit 15: ???
        BL = silicon revision number (bit 7 set if not available)
SeeAlso: AH=12h/BL=81h,AH=12h/BL=82h,AH=12h/BL=85h,AH=12h/BL=9Ah,AH=12h/BL=A1h

Values for controller type:
 0000h  no extended alternate select support
 0002h  510/520
 0003h  610/620
 0004h  5320
 0005h  6410
 0006h  5410
 0007h  6420
 0008h  6412
 0010h  5401
 0011h  5402
 0012h  5420
 0013h  5422
 0014h  5424
 0015h  5426
 0016h  5420r1
 0017h  5402r1
 0018h  5428
 0020h  6205/15/25
 0030h  5432
 0031h  5434

.