Int 10 Fn 12  - Video - Alternate Function Select (vga) - Cursor Emulatio  [V]

   AH = 12h
   BL = 34h
   AL = new state
       00h enable alphanumeric cursor emulation
       01h disable alphanumeric cursor emulation

Return: AL = 12h if function supported
Desc:  specify whether the BIOS should automatically remap cursor start/end
     according to the current character height in text modes

See Also: AH=01h,AH=03h