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library ieee;
use ieee.std_logic_1164.all;
use ieee.numeric_std.all;
entity imem is
port (
clk_i : in std_ulogic;
rden_i : in std_ulogic;
wren_i : in std_ulogic;
ben_i : in std_ulogic_vector(03 downto 0);
addr_i : in std_ulogic_vector(31 downto 0);
data_i : in std_ulogic_vector(31 downto 0);
data_o : out std_ulogic_vector(31 downto 0);
ack_o : out std_ulogic
);
end entity;
architecture imem_rtl of imem is
signal addr : std_ulogic_vector(15 downto 0);
type ram_t is array(0 to 2**15-1) of std_ulogic_vector(31 downto 0);
begin
addr <= addr_i(addr'left+2 downto 2); -- word aligned
verbose: block
begin
process(clk_i)
variable memory : ram_t;
begin
if rising_edge(clk_i) then
if wren_i then
for x in 0 to 3 loop
if ben_i(x) then
memory(to_integer(unsigned(addr)))((x+1)*8-1 downto x*8) := data_i((x+1)*8-1 downto x*8);
end if;
end loop;
end if;
end if;
end process;
process(clk_i)
variable memory : ram_t;
begin
if rising_edge(clk_i) then
if rden_i then
data_o <= memory(to_integer(unsigned(addr)));
end if;
end if;
end process;
end block;
end architecture;
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