Subversion Repositories wb4pb

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-- This sourcecode is released under BSD license.

-- Please see http://www.opensource.org/licenses/bsd-license.php for details!

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--

-- Copyright (c) 2010, Stefan Fischer <Ste.Fis@OpenCores.org>

-- All rights reserved.

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-- filename: picoblaze_wb_gpio_tb.vhd

-- description: testbench for picoblaze_wb_gpio example

-- todo4user: modify stimulus as needed

-- version: 0.0.0

-- changelog: - 0.0.0, initial release

--            - ...

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library ieee;

use ieee.std_logic_1164.all;

use ieee.numeric_std.all;

entity picoblaze_wb_gpio_tb is

end picoblaze_wb_gpio_tb;

architecture behavioral of picoblaze_wb_gpio_tb is

  component picoblaze_wb_gpio is

    port

    (

      p_rst_n_i : in std_logic;

      p_clk_i : in std_logic;

      p_gpio_io : inout std_logic_vector(7 downto 0)

    );

  end component;

  signal rst_n : std_logic := '0';

  signal clk : std_logic := '1';

  signal gpio : std_logic_vector(7 downto 0) := (others => 'Z');

  constant PERIOD : time := 20 ns;

  signal test_data_in : std_logic_vector(7 downto 4) := (others => '0');

begin

  -- system signal generation

  rst_n <= '1' after PERIOD*2;

  clk <= not clk after PERIOD/2;

  -- 4 bit counting data, changing after some micro seconds

  test_data_in <= std_logic_vector(unsigned(test_data_in) + 1) after 3000 ns;

  -- stimulus at upper gpio nibble

  gpio(7 downto 4) <= test_data_in;

  -- design under test instance

  dut : picoblaze_wb_gpio

    port map

    (

      p_rst_n_i => rst_n,

      p_clk_i => clk,

      p_gpio_io => gpio

    );

end behavioral;