CristalCaveGem » LustreC » Lustrec-Tests

-- Copyright (C) 1996 Morgan Kaufmann Publishers, Inc

-- This file is part of VESTs (Vhdl tESTs).

-- VESTs is free software; you can redistribute it and/or modify it

-- under the terms of the GNU General Public License as published by the

-- Free Software Foundation; either version 2 of the License, or (at

-- your option) any later version. 

-- VESTs is distributed in the hope that it will be useful, but WITHOUT

-- ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

-- FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

-- for more details. 

-- You should have received a copy of the GNU General Public License

-- along with VESTs; if not, write to the Free Software Foundation,

-- Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA 

-- ---------------------------------------------------------------------

--

-- $Id: ch_07_fg_07_17.vhd,v 1.2 2001-10-26 16:29:34 paw Exp $

-- $Revision: 1.2 $

--

-- ---------------------------------------------------------------------

entity fg_07_17 is

end entity fg_07_17;

architecture test of fg_07_17 is

  -- code from book

  function bv_to_natural ( bv : in bit_vector ) return natural is

    variable result : natural := 0;

  begin

    for index in bv'range loop

      result := result * 2 + bit'pos(bv(index));

    end loop;

    return result;

  end function bv_to_natural;

  -- end code from book

  signal data : bit_vector(0 to 7);

  constant address : bit_vector(0 to 3) := "0101";

  constant Taccess : delay_length := 80 ns;

begin

  tester : process is

                     constant rom_size : natural := 8;

                   constant word_size : natural := 8;

                   -- code from book (in text)

                   type rom_array is array (natural range 0 to rom_size-1)

                     of bit_vector(0 to word_size-1);

                   variable rom_data : rom_array;

                   -- end code from book

  begin

    rom_data := (X"00", X"01", X"02", X"03", X"04", X"05", X"06", X"07");

    -- code from book (in text)

    data <= rom_data ( bv_to_natural(address) ) after Taccess;

    -- end code from book

    wait;

  end process tester;

end architecture test;