git.zerfleddert.de Git - raggedstone/blob - dhwk/source/pci/address_register.vhd

   1 -- J.STELZNER
   2 -- INFORMATIK-3 LABOR
   3 -- 23.08.2006
   4 -- File: ADDR_REG.VHD
   5
   6 library IEEE;
   7 use IEEE.std_logic_1164.all;
   8
   9 entity ADDRESS_REGISTER is
  10         port (
  11                 PCI_CLOCK       :in     std_logic;
  12                 PCI_RSTn        :in     std_logic;
  13                 LOAD_ADDR_REG   :in     std_logic;
  14                 AD_REG          :in     std_logic_vector (31 downto 0);
  15                 ADDR_REG        :out    std_logic_vector (31 downto 0)
  16         );
  17 end entity ADDRESS_REGISTER;
  18
  19 architecture ADDR_REGI_DESIGN of ADDRESS_REGISTER is
  20         signal  REG_ADDR        :std_logic_vector (31 downto 0);
  21 begin
  22
  23         process (PCI_CLOCK, PCI_RSTn)
  24         begin
  25                 if      PCI_RSTn = '0'  then
  26                         REG_ADDR        <= X"00000000";
  27
  28                 elsif (rising_edge(PCI_CLOCK)) then
  29                         if LOAD_ADDR_REG = '1' then
  30                                 REG_ADDR        <=      AD_REG;
  31                         else
  32                                 REG_ADDR        <=      REG_ADDR;
  33                         end if;
  34                 end if;
  35         end process;
  36
  37         ADDR_REG        <=      REG_ADDR;
  38
  39 end architecture ADDR_REGI_DESIGN;