Subversion Repositories mips_enhanced

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

--  This file is a part of the GRLIB VHDL IP LIBRARY

--  Copyright (C) 2003, Gaisler Research

--

--  This program 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.

--

--  This program 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 this program; if not, write to the Free Software

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

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

-- Entity:      clkbuf_actel

-- File:        clkbuf_actel.vhd

-- Author:      Jiri Gaisler - Gaisler Research

-- Description: Clock buffer generator for Actel devices

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

library ieee;

use ieee.std_logic_1164.all;

-- pragma translate_off

library axcelerator;

use axcelerator.hclkint;

use axcelerator.clkint;

-- pragma translate_on

entity clkbuf_actel is

  generic(

    buftype :  integer range 0 to 3 := 0);

  port(

    i       :  in  std_ulogic;

    o       :  out std_ulogic

  );

end entity;

architecture rtl of clkbuf_actel is

  signal o2, no2, nin : std_ulogic;

  component hclkint port(a : in std_ulogic; y : out std_ulogic); end component;

  component clkint port(a : in std_ulogic; y : out std_ulogic); end component;

  attribute syn_maxfan : integer;

  attribute syn_maxfan of o2 : signal is 10000;

begin

  o <= o2;

  buf0 : if buftype = 0 generate

    o2 <= i;

  end generate;

  buf1 : if buftype = 1 generate

    buf : hclkint port map(A => i, Y => o2);

  end generate;

  buf2 : if buftype = 2 generate

    buf : clkint port map(A => i, Y => o2);

  end generate;

  buf3 : if buftype > 2 generate

    nin <= not i;

    buf : clkint port map(A => nin, Y => no2);

    o2 <= not no2;

  end generate;

end architecture;