makebits.vhd

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-- Company: 

-- Engineer: 

-- 

-- Create Date:    16:39:50 09/13/2007 

-- Design Name: 

-- Module Name:    makebits - Behavioral 

-- Project Name: 

-- Target Devices: 

-- Tool versions: 

-- Description: 

--

-- Dependencies: 

--

-- Revision: 

-- Revision 0.01 - File Created

-- Additional Comments: 

--

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library IEEE;

use IEEE.STD_LOGIC_1164.ALL;

use IEEE.STD_LOGIC_ARITH.ALL;

use IEEE.STD_LOGIC_UNSIGNED.ALL;

---- Uncomment the following library declaration if instantiating

---- any Xilinx primitives in this code.

library UNISIM;

use UNISIM.VComponents.all;

entity makebits is

    Port ( 

    CLK100     :   in    STD_LOGIC;

    leds      :  out  std_logic_vector(7 downto 0);

    pcie_rx0_p  :  in    std_logic;  -- data inputs

    pcie_rx0_n  :  in    std_logic  -- data inputs

  );

end makebits;

architecture Behavioral of makebits is

-- signals

  signal tp  :  std_logic;

  signal incomingbits  :  std_logic_vector(9 downto 0) := "0000000000";

  signal countincoming  :  std_logic_vector(3 downto 0) := "0000";

  signal khertz      : std_logic ;

  signal mhertz      : std_logic ;

  signal hertz      : std_logic ;

-- Constants

-- Components

  component zeitgeber

  port (

    clock : in  STD_LOGIC;

    mhertz_en : out  STD_LOGIC;

    khertz_en : out  STD_LOGIC;

    hertz_en : out  STD_LOGIC

  );

  end component;

begin

    IBUFDS_inst : IBUFDS 

    generic map (

      IOSTANDARD => "LVDS_25",

      DIFF_TERM => TRUE    -- Differential Termination (Virtex-4/5, Spartan-3E/3A)

    ) 

    port map (

      I => pcie_rx0_p,

      IB => pcie_rx0_n,

      O => tp

    );

  Clockgen: zeitgeber

    port map (

      clock => CLK100,

      mhertz_en => mhertz,  

      khertz_en => khertz,

      hertz_en => hertz

    );

  leds <= incomingbits (7 downto 0) when countincoming = "1010" else "00000000";

  process (mhertz)

  begin

    if mhertz'event and mhertz = '1' then

      incomingbits <= incomingbits(8 downto 0) & tp;

      countincoming <= countincoming + 1;

      if countincoming = "1010" then

        countincoming <= "0000";

      end if;

    end if;

  end process;

end Behavioral;