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library ieee;
use ieee.std_logic_1164.all;
use ieee.numeric_std.all;
entity dpram1 is
port (raddr : std_logic_vector (3 downto 0);
rdat : out std_logic_vector (7 downto 0);
waddr : std_logic_vector (3 downto 0);
wdat : std_logic_vector (7 downto 0);
clk : std_logic);
end dpram1;
architecture behav of dpram1 is
subtype memtype is std_logic_vector (16 * 8 - 1 downto 0);
signal mem : memtype;
begin
process (clk)
variable ra : natural;
variable wa : natural;
variable rlo, rhi : natural;
begin
if rising_edge (clk) then
ra := to_integer(unsigned (raddr));
rlo := ra * 8;
rhi := rlo + 7;
rdat <= mem (rhi downto rlo);
wa := to_integer(unsigned (waddr));
mem (wa * 8 + 7 downto wa * 8) <= wdat;
end if;
end process;
end behav;
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