Int 15 Fn 22  - System - Later Ps/2s - Locate ROM BASIC                    [B]

   AH = 22h

Return: CF set on error
       AH = status (86h if function not supported)
   CF clear on success
       AH = 00h
       ES:BX -> ROM BASIC

Note:  if this function is not supported, ROM BASIC is at F600h:0000h

See Also: INT 86"BASIC",INT F0"BASIC"