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library ieee;
use ieee.std_logic_1164.all;
library ieee;
use ieee.numeric_std.all;
entity lmask is
port (
clk : in std_logic;
ra0_addr : in std_logic_vector(4 downto 0);
ra0_data : out std_logic_vector(31 downto 0)
);
end lmask;
architecture augh of lmask is
-- Embedded RAM
type ram_type is array (0 to 31) of std_logic_vector(31 downto 0);
signal ram : ram_type := (
"00000000000000000000000000000001", "00000000000000000000000000000011", "00000000000000000000000000000111",
"00000000000000000000000000001111", "00000000000000000000000000011111", "00000000000000000000000000111111",
"00000000000000000000000001111111", "00000000000000000000000011111111", "00000000000000000000000111111111",
"00000000000000000000001111111111", "00000000000000000000011111111111", "00000000000000000000111111111111",
"00000000000000000001111111111111", "00000000000000000011111111111111", "00000000000000000111111111111111",
"00000000000000001111111111111111", "00000000000000011111111111111111", "00000000000000111111111111111111",
"00000000000001111111111111111111", "00000000000011111111111111111111", "00000000000111111111111111111111",
"00000000001111111111111111111111", "00000000011111111111111111111111", "00000000111111111111111111111111",
"00000001111111111111111111111111", "00000011111111111111111111111111", "00000111111111111111111111111111",
"00001111111111111111111111111111", "00011111111111111111111111111111", "00111111111111111111111111111111",
"01111111111111111111111111111111", "11111111111111111111111111111111"
);
-- Little utility functions to make VHDL syntactically correct
-- with the syntax to_integer(unsigned(vector)) when 'vector' is a std_logic.
-- This happens when accessing arrays with <= 2 cells, for example.
function to_integer(B: std_logic) return integer is
variable V: std_logic_vector(0 to 0);
begin
V(0) := B;
return to_integer(unsigned(V));
end;
function to_integer(V: std_logic_vector) return integer is
begin
return to_integer(unsigned(V));
end;
begin
-- The component is a ROM.
-- There is no Write side.
-- The Read side (the outputs)
ra0_data <= ram( to_integer(ra0_addr) );
end architecture;
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