利用硬件描述语言实现交通灯控制模型7，黑夜模式，无人按键

黑夜无人按键

模块说明：当白天黑夜计数器输出的状态量为‘0’并且中间信号strobe无效时，代表黑夜时没有人按键，则显示管固定显示，没有变化

 

LIBRARY IEEE;

USE IEEE.STD_LOGIC_1164.ALL;

 

 

ENTITY  heiye2  IS

 

port ( NUM01,NUM11,NUM21,NUM31 : buffer STD_LOGIC_VECTOR(3 DOWNTO 0);

strobe: in std_logic; --------与clk_out1组成使能端的电平状态 0 表示无按键  1 有

clk_out2 : in std_logic;  ------100hz扫频

      count_day:in std_logic ); -----白天黑夜状态量

end entity heiye2;

 

ARCHITECTURE rtl OF heiye2 IS

 

 

signal num0: STD_LOGIC_VECTOR(3 DOWNTO 0);

signal num1: STD_LOGIC_VECTOR(3 DOWNTO 0);

signal num2: STD_LOGIC_VECTOR(3 DOWNTO 0);

signal num3: STD_LOGIC_VECTOR(3 DOWNTO 0);

 

begin

 

PPPPP: process(clk_out2)

begin

    if(strobe= '0') then

   if count_day= '1' then

num0 <= "0011";

num1 <= "0000";

num2 <= "0000";

      num3 <= "0000";

end if;

end if;

end process PPPPP;

 

num01 <= num0;

num11 <= num1;

num21 <= num2;

num31 <= num3;

 

end rtl;