INT 10H 12H BL=10H: Get EGA Information

                                                      Compatibility: EGA VGA 
 Expects: AH    12H
          BL    10H
 Returns: BH    default BIOS setup (0=color; 1=monochrome)
          BL    mem size code (0=64K; 1=128K; 2=192K; 3=256K)
                (Note: if BL>4, then this is not an EGA BIOS)
          CH    feature bits (values of those RCA connectors)
          CL    switch settings
    Info: This obtains miscellaneous information about the EGA switch
          settings and the current values of the "feature bits" as read
          through those rarely-used RCA connectors on some EGA cards.

          If upon return from this call, BL>4, then you must be running on
          a CGA or MDA (not an EGA or VGA).

See Also: INT 10H 12H (EGA/VGA Special Functions/Alternate Select)
          INT 10H: Video Services