-- File: full_add.adb
-- Author: Sy Wong
-- Date: 7/98
-- Aim: Implements a one bit adder 

package body FULL_ADD is
-- An alternative implementation, with NAND, NOR, INVERT and X_OR components
-- for example, is possible.
  procedure update(d: in out device) is
  begin
    d.sum := d.input1 xor d.input2 xor d.carry_in;
    d.carry_out:= ((d.input1 or d.input2) and d.carry_in) or
                   (d.input1 and d.input2);
  end update;
end FULL_ADD;