library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
use IEEE.STD_LOGIC_ARITH.ALL;
use IEEE.STD_LOGIC_UNSIGNED.ALL;

--  Uncomment the following lines to use the declarations that are
--  provided for instantiating Xilinx primitive components.
--library UNISIM;
--use UNISIM.VComponents.all;

entity SYFIFO is

 generic(FIFO_Depth : integer :=10; FIFO_Width : integer :=10);
 port(
   read_clock_in : in std_logic;
   write_clock_in : in std_logic;
   read_enable_in : in std_logic;
   write_enable_in : in std_logic;
   full_out : out std_logic;
   empty_out: out std_logic;
   reset_in : in std_logic;
   write_data_in : in std_logic_vector(FIFO_Width-1 downto 0);
   read_data_out : out std_logic_vector(FIFO_Width-1 downto 0));

end SYFIFO;

architecture FIFOArc of SYFIFO is

 type BlockRam is array (0 to FIFO_Depth-1) of std_logic_vector(FIFO_Width-1 downto 0);
 signal RAM : BlockRam;
 signal read_clk : std_logic;
 signal write_clk : std_logic;
 signal read_enable : std_logic;
 signal write_enable : std_logic;
 signal full : std_logic;
 signal empty : std_logic;
 signal reset : std_logic;
 signal read_addr : integer range 0 to FIFO_Depth-1;--std_logic_vector(9 downto 0);
 signal write_addr : integer range 0 to FIFO_Depth-1;--std_logic_vector(9 downto 0);

begin

 read_enable <= read_enable_in;
 write_enable <= write_enable_in;
 read_clk <= read_clock_in;
 write_clk <= write_clock_in;
 full_out <= full;
 empty_out <= empty;
 reset <= reset_in;

 
 -------------------------------------------------------
 --读地址指针信号的产生
 -------------------------------------------------------
 proc1:process(read_clk,reset)
 begin
 if (reset='1') then
  read_addr <= FIFO_Depth-1;
 elsif (read_clk'event and read_clk='1') then
  if (read_enable='1' and empty='0') then
   if (read_addr=FIFO_Depth-1) then
    read_addr<=0;
   else
    read_addr <= read_addr+1;
   end if;
  end if;
 end if;
 end process proc1;

 -------------------------------------------------------
 --写地址指针信号的产生
 -------------------------------------------------------
 proc2:process(write_clk,reset)
 begin
 if (reset='1') then
  write_addr <= 0;
 elsif (write_clk'event and write_clk='1') then
  if (write_enable='1' and full='0') then
   if(write_addr=FIFO_Depth-1) then
    write_addr <=0;
   else
    write_addr <= write_addr+1;
   end if;
  end if;
 end if;
 end process proc2;

 --------------------------------------------------------
 ---读操作
 --------------------------------------------------------
 proc3:process(read_clk)
 begin
 if (read_clk'event and read_clk='1') then
  if (read_enable='1' and empty='0') then
   read_data_out <= RAM(read_addr);
  end if;
 end if;
 end process proc3;

 -------------------------------------------------------
 ----写操作
 --------------------------------------------------------
 proc4:process(write_clk)
 begin
 if (write_clk'event and write_clk='1') then
  if (write_enable='1' and full='0') then
   RAM(write_addr) <= write_data_in;
  end if;
 end if;
 end process proc4;

 ------------------------------------------------------
 --空标志和读使能信号的产生
 ------------------------------------------------------
 proc5:process(read_clk,reset)
 begin
 if (reset='1') then
  empty <= '1';
  read_enable <= '0';
 elsif (read_clk'event and read_clk='1') then
  if ((read_addr=write_addr-2 or (read_addr=FIFO_Depth-1 and write_addr=1) or (read_addr=FIFO_Depth-2 and write_addr=0)) and (read_enable='0' and write_enable='1')) then
   empty <='1';
   read_enable <= '0';
  elsif (empty='1' and  write_enable='0') then
   empty <='0';
   read_enable <= '1';
  end if;  
 end if;
 end process proc5;

 ------------------------------------------------------
 --满标志和写使能信号的产生
 ------------------------------------------------------
 proc6:process(write_clk,reset)
 begin
 if (reset='1') then
  full <= '0';
  write_enable <= '0';
 elsif (write_clk'event and write_clk='1') then
  if (read_addr=write_addr and read_enable='1' and write_enable='0') then
   full <='1';
   write_enable <= '0';
  elsif (full='1' and read_enable='0') then
   full <='0';
   write_enable <= '1';
  end if;
 end if;
 end process proc6;

 ---------------------------------------------------------
 ---输出空满标志信号
 ---------------------------------------------------------
 proc7:process(write_clk)
 begin
 if (write_clk'event and write_clk='1') then
  full_out <= full;
  empty_out <= empty;
   end if;
 end process proc7;

end FIFOArc;
，这个程序不能综合，急急急！！！！