cnt.vhd

一个简单的交通灯程序(包括验证,主程序,和译码程序),在ALTER DE2板上实现

library ieee;
use ieee.std_logic_1164.all;
use ieee.std_logic_unsigned.all;
entity cnt is
port(clk: in std_logic;
    cout: out std_logic);
end cnt;
architecture behav of cnt is
begin 
process(clk)
variable q: std_logic_vector(25 downto 0);
     begin
       if clk'event and clk='1' then
            q:=q+1;
end if;
if q="1100110111111110011000000" then cout<='1';
else cout<='0';
end if;
end process;
end behav;