controller.vhd

max_plus开发的 有max_plus就可以直接运行的交通灯制作 用vhdl语言编写的

LIBRARY IEEE;
USE IEEE.Std_Logic_1164.All;

ENTITY Controller IS
PORT
  ( Clock: in Std_Logic;
    Hold: in Std_Logic;
    CountNum: in Integer range 0 to 49; 
    NumA,NumB: out Integer range 0 to 25;
    RedA,GreenA,YellowA: Out Std_Logic;
    RedB,GreenB,YellowB: Out Std_Logic;
    Flash: OUT Std_Logic
  );
end;

Architecture Behavior of Controller Is
Begin
  process(clock)
  begin
    if falling_edge(Clock) then
        if hold='1' then
           RedA<='1';
           RedB<='1';
           GreenA<='0';
           GreenB<='0';
           YellowA<='0';
           YellowB<='0';
           Flash<='1';
        else
           Flash<='0';
           if CountNum<=19 then
              NumA<=20-CountNum;
              RedA<='0';
              GreenA<='1';
              YellowA<='0';
           elsif CountNum<=24 then
              NumA<=25-CountNum;
              RedA<='0';
              GreenA<='0';
              YellowA<='1';
           else
              NumA<=50-CountNum;
              RedA<='1';
              GreenA<='0';
              YellowA<='0';
           end if;
           
           if CountNum<=24 then
              NumB<=25-CountNum;
              RedB<='1';
              GreenB<='0';
              YellowB<='0';
           elsif (CountNum<=44) then
              NumB<=45-CountNum;
              RedB<='0';
              GreenB<='1';
              YellowB<='0';
           else
              NumB<=50-CountNum;
              RedB<='0';
              GreenB<='0';
              YellowB<='1';
           end if;
        end if;
    end if;
  end process;
end;