VHDL PROGRAM OF A74XX00-Test_vhd

-- ============================================================================
-- 74XX00 Quad 2-Input NAND Gates (Test Bench)
--
-- Copyright (C),2004 Andrew John Jacobs.
--
-- This program is provided free of charge for educational purposes
--
-- Redistribution and use in binary form without modification, is permitted
-- provided that the above copyright notice, this list of conditions and the
-- following disclaimer in the documentation and/or other materials provided
-- with the distribution.
--
-- THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS 'AS IS' AND ANY
-- EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
-- WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
-- DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR ANY
-- DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
-- (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
-- LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
-- ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-- (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
-- THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-- ============================================================================


library ieee;
use ieee.std_logic_1164.all;

entity A74XX00_TestBench is
end entity;

-- ============================================================================

library ieee;
use ieee.std_logic_1164.all;

architecture behaviour of A74XX00_TestBench is
 component A74XX00 is
  generic (
   tplh  : time;
   tphl  : time);
  port (
   a1   : in  std_logic;
   b1   : in  std_logic;
   a2   : in  std_logic;
   b2   : in  std_logic;
   a3   : in  std_logic;
   b3   : in  std_logic;
   a4   : in  std_logic;
   b4   : in  std_logic;
   o1   : out  std_logic;
   o2   : out  std_logic;
   o3   : out  std_logic;
   o4   : out  std_logic);
 end component;

 signal ab : std_logic_vector (1 to 2);
 signal wx : std_logic_vector (1 to 2);
 signal o : std_logic_vector (1 to 4);
begin
 -- Normal test pattern
 ab <= "UU",

   "00" after 10 ns,
   "01" after 20 ns,
   "10" after 30 ns,
   "11" after 40 ns,

   "LL" after 50 ns,
   "LH" after 60 ns,
   "HL" after 70 ns,
   "HH" after 80 ns;

 -- Inverted test pattern
 wx <= "UU",

   "11" after 10 ns,
   "10" after 20 ns,
   "01" after 30 ns,
   "00" after 40 ns,

   "HH" after 50 ns,
   "HL" after 60 ns,
   "LH" after 70 ns,
   "LL" after 80 ns;

 -- Connect the testbench to the component
 nand2: A74XX00
  generic map (
   tplh => 5 ns, tphl => 7 ns)
  port map (
   ab(1), ab(2),
   ab(1), wx(2),
   wx(1), ab(2),
   wx(1), wx(2),
   o(1), o(2), o(3), o(4));
end architecture;