jiao_tong.vhd

在quartus开发环境下

library ieee;
use ieee.std_logic_1164.all;
use ieee.std_logic_unsigned.all;
entity jiao_tong is
port(clk:in std_logic;----20mhz晶振时钟
     jin:in std_logic;----禁止通行信号
     scan:out std_logic_vector(1 downto 0);--------数码管地址选择信号
     seg7:out std_logic_vector(6 downto 0);--------7段显示控制信号(abcdefg) 
     ra,ya,ga:out std_logic;-----------主干道的红黄绿灯
     rb,yb,gb:out std_logic);----------支干道的红黄绿灯
end;
architecture one of jiao_tong is
	type states is(st1,st2,st3,st4);------四种状态
	signal clk1khz,clk1hz:std_logic;------分频信号包括1khz和1hz
	signal one,ten:std_logic_vector(3 downto 0);--倒计时的个位和十位
	signal cnt:std_logic_vector(1 downto 0);------数码管扫描计数信号
	signal data:std_logic_vector(3 downto 0);
	signal seg7_temp:std_logic_vector(6 downto 0);
	signal r1,r2,g1,g2,y1,y2:std_logic;
begin
------------------------------------1khz分频------
process(clk)
variable count:integer range 0 to 9999;
begin
if clk'event and clk='1' then 
  if count=9999 then clk1khz<=not clk1khz;count:=0;
  else count:=count+1;
  end if;
end if;
end process;
-------------------------------------1hz分频-----
process(clk1khz)
	variable count:integer range 0 to 499;
begin
if clk1khz'event and clk1khz='1' then 
  if count=499 then clk1hz<=not clk1hz;count:=0;
  else count:=count+1;
  end if;
end if;
end process; 
--------------------------------------交通状态转换-----
process(clk1hz)
	variable stx:states;
	variable a:std_logic;-------倒计时赋值标志位
	variable qh,ql:std_logic_vector(3 downto 0);-----计数的高位和低位
begin
if clk1hz'event and clk1hz='1' then
case stx is
when st1=>if jin='0' then---------------------------------------状态st1，主干道通行35秒
             if a='0' then 
                 qh:="0011";-----高位为3
                 ql:="0100";-----低位为4
                 a:='1';
	             r1<='0';
	             y1<='0';
	             g1<='1';-----主干道绿灯亮
	             r2<='1';-----支干道红灯亮
	             y2<='0';
	             g2<='0';
	          else 
	               if qh=0 and ql=1 then ----如果倒计时结束则转到st2状态
	                    stx:=st2;
	                    a:='0';
	                    qh:="0000";
	                    ql:="0000";
	               elsif ql=0 then ------实现倒计时
						ql:="1001";
						qh:=qh-1;
	               else 
	                    ql:=ql-1;
	               end if;
	          end if;
	      end if;
when st2=>if jin='0' then --------------------------------状态st2，主干道黄灯倒计时5秒
     	     if a='0' then 
                 qh:="0000";-----高位为0
                 ql:="0100";-----低位为4
                 a:='1';
                 r1<='0';
				 y1<='1';----主干道黄灯点亮
				 g1<='0';
				 r2<='1';----支干道红灯点亮
				 y2<='0';
				 g2<='0';
	          else 
	               if   ql=1 then  ----如果倒计时结束则转到st3状态
						stx:=st3;
						a:='0';
						qh:="0000";
						ql:="0000";
	               else 
	                    ql:=ql-1;
	               end if;
	          end if;
	      end if;
when st3=>if jin='0' then --------------------------------------状态st3，支干道通行25秒
	          if a='0' then 
				  qh:="0010";----高位为2
				  ql:="0100";----低位为4
				  a:='1';
	              r1<='1';-------主干道红灯点亮
				  y1<='0';
				  g1<='0';
				  r2<='0';
				  y2<='0';
				  g2<='1';-------支干道绿灯点亮
	          else 
	               if qh=0 and ql=1 then ----如果倒计时结束则转到st4状态
						stx:=st4;
						a:='0';
						qh:="0000";
						ql:="0000";
	               elsif ql=0 then -----实现倒计时25s
	                     ql:="1001";
						 qh:=qh-1;
	               else 
	                     ql:=ql-1;
	               end if;
	          end if;
	      end if;
when st4=>if jin='0' then ----------------------------------状态st4，支干道黄灯倒计时5秒
	          if a='0' then
				  qh:="0000";----高位为0
				  ql:="0100";----低位为4
				  a:='1';
				  r1<='1';-------主干道红灯点亮
				  y1<='0';
				  g1<='0';
				  r2<='0';
				  y2<='1';-------支干道绿灯点亮
				  g2<='0';
	          else 
	               if  ql=1 then  ----如果倒计时结束则转到st1状态
					   stx:=st1;
					   a:='0';
					   qh:="0000";
					   ql:="0000";
	               else
	                   ql:=ql-1;
	               end if;
	          end if;
	      end if;
end case;
end if;
	one<=ql;ten<=qh;
end process;
---------------------------------禁止通行信号，数码管闪烁显示---------------
process(jin,clk1hz,r1,r2,g1,g2,y1,y2,seg7_temp)
begin
if jin='1' then
    ra<=r1 or jin;--------主干道红灯点亮
    rb<=r2 or jin;--------支干道红灯点亮
    ga<=g1 and not jin;
	gb<=g2 and not jin;
	ya<=y1 and not jin;
	yb<=y2 and not jin;
	------------------------------实现显示闪烁
	seg7(0)<=seg7_temp(0) and clk1hz;
	seg7(1)<=seg7_temp(1) and clk1hz;
	seg7(2)<=seg7_temp(2) and clk1hz;
	seg7(3)<=seg7_temp(3) and clk1hz;
	seg7(4)<=seg7_temp(4) and clk1hz;
	seg7(5)<=seg7_temp(5) and clk1hz;
	seg7(6)<=seg7_temp(6) and clk1hz;
else 
    seg7<=seg7_temp;
	ra<=r1;
	rb<=r2;
	ga<=g1;
	gb<=g2;
	ya<=y1;
	yb<=y2;
end if;
end process;
------------------------------------数码管动态扫描计数--------
process(clk1khz)
begin
if clk1khz'event and clk1khz='1' then  
      if cnt="01" then cnt<="00";
      else cnt<=cnt+1;
      end if;
end if;
end process;
-------------------------------------数码管动态扫描-----------
process(cnt,one,ten)
begin
case cnt is
	when "00"=> data<=one;scan<="01";
	when "01"=> data<=ten;scan<="10";
	when others=>null;
end case;
end process;  
-----------------------------------------七段译码--------------------
process(data)
begin
case data is
    when"0000"=>seg7_temp<="1111110";-----0显示
	when"0001"=>seg7_temp<="0110000";-----1显示
	when"0010"=>seg7_temp<="1101101";-----2显示
	when"0011"=>seg7_temp<="1111001";-----3显示
	when"0100"=>seg7_temp<="0110011";-----4显示
	when"0101"=>seg7_temp<="1011011";-----5显示
	when"0110"=>seg7_temp<="1011111";-----6显示
	when"0111"=>seg7_temp<="1110000";-----7显示
	when"1000"=>seg7_temp<="1111111";-----8显示
	when"1001"=>seg7_temp<="1111011";-----9显示
    when others=>seg7_temp<="1001111";----E显示，代表出错
end case;
end process;
end;