source: PROJECT_CORE_MPI/CORE_MPI/TRUNK/RAM_32_32.vhd

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-- Company: 
-- Engineer:  GAMOM NGOUNOU 
-- 
-- Create Date:    18:33:31 03/05/2012 
-- Design Name: 
-- Module Name:    RAM_32_32 - Behavioral 
-- Project Name: MPI_Core
-- Target Devices: 
-- Tool versions: 
-- Description: permet de stocker les données locales de la librairie MPI
--
-- 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 using
-- arithmetic functions with Signed or Unsigned values
--use IEEE.NUMERIC_STD.ALL;

-- Uncomment the following library declaration if instantiating
-- any Xilinx primitives in this code.
--library UNISIM;
--use UNISIM.VComponents.all;

entity RAM_v is
generic(width : positive:=32; Size:positive:=16);
Port ( clka, clkb : in std_logic;
                          wea : in std_logic;
                          ena, enb : in std_logic;
                          addra, addrb : in std_logic_vector(size-1 downto 0); --cinq lignes d'adresse
                          dia : in std_logic_vector(width-1 downto 0);
                          dob : out std_logic_vector(width-1 downto 0));
end RAM_v;

architecture Behavioral of RAM_v is
        signal Lra,Lrb :std_logic:='0';
        signal sel : std_logic_vector(1 downto 0);
        signal doa,dout : std_logic_vector(width-1 downto 0);
        type ram_type is array (2**size-1 downto 0) of std_logic_vector (width-1 downto 0);
        signal RAM: ram_type;
begin
 process (clka)
        begin
                if clka'event and clka = '1' then
                        if ena = '1' then
                                if wea = '1' then
                                        RAM(conv_integer(addra)) <= dia;
                                end if;
                                        
                                doa<=RAM(conv_integer(addrb));
                                Lra<='1';
                        else 
                                if lrb='1' then
                                                Lra<='0';
                                end if;
                        end if;
                 end if;
 end process;

 
 process (clkb) 
 begin
                if clkb'event and clkb = '1' then
                        if enb = '1' then
                                Lrb<='1';       
                                dout <= RAM(conv_integer(addrb)) ;
                        else
                                if Lra='1' then
                                        Lrb<='0';
                                end if;
                        end if;
                end if;
 end process;
 
 sel<=(Lra,Lrb);
 With  sel select
 dob <=dout when "11",
      doa  when "10",
                dout when "01",
                dout when "00",
                dout when others;
                
end Behavioral;