Files
psi-tp4/traffic_light.vhdl
Tiago Batista Cardoso 6e000cdcaa working implementation
2025-12-26 12:20:48 +01:00

84 lines
2.2 KiB
VHDL

library ieee;
use ieee.std_logic_arith.all;
use ieee.std_logic_1164.all;
entity traffic_light is
port (
rst,
clk : in std_logic;
red,
orange,
green : out std_logic
);
end entity traffic_light;
architecture V1 of traffic_light is
component count is
port(
rst,
clk : in std_logic;
input : in std_logic_vector (31 downto 0);
output : out std_logic_vector (31 downto 0)
);
end component;
component tick1s is
port (
rst,
clk : in std_logic;
output : out std_logic
);
end component;
signal counter_in : std_logic_vector (31 downto 0) := (others => '0');
signal counter_out : std_logic_vector (31 downto 0);
signal s_clk : std_logic;
begin
G1: entity work.tick1s(V1)
port map(
rst => rst,
clk => clk,
output => s_clk
);
G2: entity work.count(V1)
port map(
rst => rst,
-- on utilise le signal de sortie du tick1s comme clock pour notre counter.
clk => s_clk,
in_s => counter_in,
out_s => counter_out
);
process(clk, rst) -- state machine
begin
if rising_edge(clk) then
if rst = '1' then
green <= '1';
orange <= '0';
red <= '0';
else
-- 10 seconds green light
if counter_out < x"0000000a" then
green <= '1';
orange <= '0';
red <= '0';
-- 2 seconds orange light
elsif counter_out < x"0000000c" then
green <= '0';
orange <= '1';
red <= '0';
-- 10 seconds red light
elsif counter_out < x"00000016" then
green <= '0';
orange <= '0';
red <= '1';
-- reset
else
counter_in <= (others => '0');
end if;
if s_clk = '1' then
counter_in <= counter_out;
end if;
end if;
end if;
end process;
end architecture V1;