vhdl红绿灯实验.doc

南北方向和东西方向的共六个颜色灯（红、黄、绿）按给定延迟时间循环点亮。东西方向通行30秒，南北方向通行30秒。选用2个七段码显示时间，进行倒计时。当时间到后，进行红黄绿灯显示切换。交通灯控制器的4个状态南北公路东西公路状态0 25秒绿红状态1 5秒红灯红+黄状态2 25秒红绿状态3 5秒红+黄红交通灯控制器的状态转换图library ieee;use ieee.std_logic_1164.all;use ieee.std_logic_unsigned.all;entity traffic_signal_light is port (clk:instd_logic;clr:instd_logic;rst:instd_logic; dig_sel_n:out std_logic_vector(7 downto 0);ewsn : out std_logic_vector(5 downto 0);dat_out:out std_logic_vector(7 downto 0);useless : out std_logic_vector(5 downto 0);end entity traffic_signal_light;architecture bhv of traffic_signal_light istype states is (S0,S1,S2,S3);signal current_state,next_state : states := S0; signal dig0,dig1,dig2,dig3 : std_logic_vector(7 downto 0);signal digSelectAddress : integer range 0 to 3;-当前将要显示数码管的地址控制线； signal data1: integer range 40 downto 0 ; -data = 送显示的时钟数字信号；signal data2 : integer range 40 downto 0 ;signal clock_1s : std_logic;signal clock_5ms: std_logic;-数码管的译码函数- - 形参 data :为要译码的数字，范围为：09； - 返回值 ledSegment :为译码好的七段数码管断码；function decode( data: integer range 0 to 9 )return std_logic_vector isvariable ledSegment: std_logic_vector(7 downto 0);beginCASE data ISWHEN 0 =ledSegment := 11000000;- 0xC0;0 WHEN 1 =ledSegment := 11111001;- 0xf9;1WHEN 2 =ledSegment := 10100100;- 0xa4;2WHEN 3 =ledSegment := 10110000;- 0xb0 3WHEN 4 =ledSegment := 10011001;- 0x99 4WHEN 5 =ledSegment := 10010010;- 0x92;5WHEN 6 =ledSegment := 10000010;- ox82;6WHEN 7 =ledSegment := 11111000;- 0xf8;7WHEN 8 =ledSegment := 10000000;- 0x80;8WHEN 9 =ledSegment := 10010000;- 0x90;9WHEN OTHERS =null; END CASE; return ledSegment;end decode;-begin -architecture useless = 111111;dig1 = decode(data1 /10 rem 10);dig0 = decode(data1 rem 10 );dig3 = decode(data2 /10 rem 10);dig2 ewsn = 110011;-rgif(data1 = 1 ) then next_state = S1 ;else next_state ewsn = 101011;-ryif(data1 = 1 ) then next_state = S2 ;else next_state ewsn = 011110;if( data1 = 5 ) then next_state = S3 ;else next_state ewsn = 011101;if( data1 = 1 ) then next_state = S0 ;else next_state = S3 ;end if ;end case ;end process Change_state;-时序进程-Reg : process(clock_1s,rst)beginif rst = 1 then current_state = S0;elsif (clock_1s = 1 and clock_1sevent) thencurrent_state = 10_000_000) thenclock_1s = 0;elseclock_1s = 1;end if;end if; end process Div_clock_1s; -25秒和5秒倒计时- -东西红路灯数码管倒计时- counter1 : process(clock_1s) variable data_60second : integer range 60 downto 1 ; begin if(clock_1sevent and clock_1s = 1)thenif( data1 = 0 ) thendata_60second := 60;data1 35 ) thendata1 30) thendata1 = (data_60second - 30 ) ;elsedata1 = data_60second;end if;end if;end if;end if;end process counter1; -南北红路灯数码管倒计时- counter2 : process(clock_1s) variable data_60second : integer range 60 downto 1 ; begin if(clock_1sevent and clock_1s = 1)thenif( data2 = 0 ) thendata_60second := 60;data2 30 ) thendata2 5) thendata2 = (data_60second - 5 ) ;else data2 = 50_000) thenclock_5ms = 0;elseclock_5ms = 1;end if;end if; end process Div_clock_5ms;-counter3 : process(clock_5ms) beginif(clock_5ms = 1 and clock_5msevent) thenif digSelectAddress = 3 thendigSelectAddress = 0;elsedigSelectAddress dig_s