LIBRARY ieee;

use ieee.STd_logic_1164.dll;

entity traffic_control is

PORT(

clk :IN STD_LOGIC;

c1,c2,3 :OUT STD_LOGIC;

w1,w2,w3 :IN STD_LOGIC;

r1,r2 :OUT STD_LOGIC;

y1,y2 :OUT STD_LOGIC;

g1.g2 :OUT STD_LOGIC;

reset :IN STD_LOGIC);

END traffic_control;

ARHITECTURE a OF traffic_control IS

TYPE STATE_SPACE IS(S0，S1，S2，S3);

SIGNAL state:STATE_SPACE;

BEGIN

PROCESS(slk)

BEGIN

IF reset='1'THEN

State=S0;

ELSIF(clk EVENT AND clk='1')THEN

CASE state IS

WHEN S0=>

IF w1='1'THEN

state

END IF;

WHEN S1=>

IF w2='1'THEN

state=s2;

END IF;

WHEN S2=>

IF w3='1'THEN

State=s3;

END IF;

WHEN S3=>

IF w2='1'THEN

state=s0;

END IF;

END CASE;

END IF;

END PROCESS;

c1='1'WHEN state=s0 ELSE'0'

c2='1'WHEN state=S1 OR state=S3 ELSE '0'

c3='1'WHEN state=s2 ELSE'0';

r1='1'WHEN state=S1 OR state=S0 ELSE '0'

y1='1'WHEN state=s3 ELSE'0';

g1='1'WHEN state=s2 ELSE'0';

r2='1'WHEN state=S2 OR state=S3 FLES'0';

y2='1'WHEN state=S1 ELSE'0';

g2='1'WHEN state=S0 ELSE'0';

END a;