-- True Random octets generator reading from an FG and using Raw_Types.
 -- S.MG, 2018

with Ada.Sequential_IO;
with Interfaces;
with Raw_Types;

package RNG is

  -- for reading from the FG one Octet at a time
  package Octet_IO is new Ada.Sequential_IO(Element_Type => 
                                              Interfaces.Unsigned_8);

  -- path to the FG; NB: the FG has to be initialized prior to using SMG Comms!
  RNG_PATH: constant String := "/dev/ttyUSB0";

  -- exception raised when FG is not accessible / read fails 
  FG_Failure : exception;

  -- reads O'Length octets from the FG at RNG_PATH
  procedure Get_Octets( O: out Raw_Types.Octets );
end RNG;