请用ahdl语言描述十字路口信号灯,需要实现的功能如下:总共60秒为周期,每条道路30秒,有红绿黄三个灯,顺序为红灯30秒,绿灯27秒,黄灯3秒,两条道路通行错开,每条道路有数字显示屏显示该道路剩余通行时间
时间: 2024-03-27 09:35:29 浏览: 14
以下是ahdl语言描述的十字路口信号灯:
```
--定义信号灯状态
type state_type is (red, green, yellow);
--定义十字路口信号灯模块
module traffic_light(clock, reset, road1_red, road1_green, road1_yellow, road1_display, road2_red, road2_green, road2_yellow, road2_display);
input clock, reset;
output road1_red, road1_green, road1_yellow, road1_display, road2_red, road2_green, road2_yellow, road2_display;
--定义状态机状态
signal state: state_type;
--定义计时器
signal timer: integer range 0 to 60;
--定义计时器计数
signal counter: integer range 0 to 29;
--定义状态转移条件
signal to_red, to_green, to_yellow: boolean;
--定义两条道路的状态
signal road1_state, road2_state: state_type;
--定义两条道路的计时器
signal road1_timer, road2_timer: integer range 0 to 30;
begin
--初始化状态机
process(clock, reset)
begin
if reset = '1' then
state <= red;
timer <= 0;
counter <= 0;
to_red <= false;
to_green <= false;
to_yellow <= false;
road1_state <= red;
road2_state <= green;
road1_timer <= 30;
road2_timer <= 27;
elsif rising_edge(clock) then
if to_red = true then
state <= red;
timer <= 0;
counter <= 0;
to_red <= false;
to_green <= false;
to_yellow <= false;
road1_state <= red;
road2_state <= green;
road1_timer <= 30;
road2_timer <= 27;
elsif to_green = true then
state <= green;
timer <= 0;
counter <= 0;
to_red <= false;
to_green <= false;
to_yellow <= false;
road1_state <= green;
road2_state <= red;
road1_timer <= 27;
road2_timer <= 30;
elsif to_yellow = true then
state <= yellow;
timer <= 0;
counter <= 0;
to_red <= false;
to_green <= false;
to_yellow <= false;
road1_state <= yellow;
road2_state <= yellow;
road1_timer <= 3;
road2_timer <= 3;
elsif timer >= 60 then
if state = red then
to_green <= true;
elsif state = green then
to_yellow <= true;
elsif state = yellow then
to_red <= true;
end if;
else
timer <= timer + 1;
if counter >= 29 then
counter <= 0;
else
counter <= counter + 1;
end if;
end if;
end if;
end process;
--定义信号灯状态输出
road1_red <= '1' when road1_state = red else '0';
road1_green <= '1' when road1_state = green else '0';
road1_yellow <= '1' when road1_state = yellow else '0';
road2_red <= '1' when road2_state = red else '0';
road2_green <= '1' when road2_state = green else '0';
road2_yellow <= '1' when road2_state = yellow else '0';
--定义数字显示屏输出
road1_display <= std_logic_vector(to_unsigned(road1_timer, 4));
road2_display <= std_logic_vector(to_unsigned(road2_timer, 4));
end module;
```
上述代码定义了一个状态机,实现了十字路口信号灯的功能。其中,计时器用于计算整个周期的时间,计数器用于计算每个灯的时间,状态转移条件用于控制状态转移,两条道路的状态和计时器用于控制道路的灯光和数字显示屏。