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library ieee;
use ieee.std_logic_1164.all;
library ieee;
use ieee.numeric_std.all;
entity wh_code_table is
port (
clk : in std_logic;
ra0_data : out std_logic_vector(31 downto 0);
ra0_addr : in std_logic_vector(1 downto 0)
);
end wh_code_table;
architecture augh of wh_code_table is
-- Embedded RAM
type ram_type is array (0 to 3) of std_logic_vector(31 downto 0);
signal ram : ram_type := ("00000000000000000000001100011110", "11111111111111111111111100101010", "00000000000000000000001100011110", "11111111111111111111111100101010");
-- 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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