huang.v

东西和南北方向各有一组红、黄、绿灯用于指挥交通

/*led_seg从左开始是a，最右边是g
led_dig从左到右*
2亮 3不亮*/
module huang(clk, led_seg,led_dig,led,reset);
input clk;
output [7:0]led_seg;
output [7:0]led_dig;
output [7:0]led;
input reset;
reg [7:0]led_seg;
reg [7:0]led_dig;
reg [7:0]led;
reg [23:0]cout;
reg [20:0]couta;
reg [5:0]seconds;
reg f1;
reg f100;
reg [3:0]shi_left;
reg [3:0]ge_left;
reg [3:0]shi_right;
reg [3:0]ge_right;
reg [1:0]g;
reg [4:0]state;

//设置时间间隔是一秒
always @ (posedge clk)
begin
	if(cout==9999999)
		begin
			f1<=~f1;
			cout<=0;
		end
	else
		begin
			cout<=cout+1;
		end
end
//分频得到用于数字显示的频率
always @ (posedge clk)
begin
	if(couta==999)
		begin
			f100<=~f100;
			couta<=0;
		end
	else
		begin
			couta<=couta+1;
		end
end
//交通灯显示一次的周期
always @(posedge f1)
begin
	if(seconds==50)
		begin
			seconds<=0;
		end
	else 
		begin
			seconds<=seconds+1;
		end
end
//显示交通指示灯的时间变换
always @ (posedge f100)
begin

	g<=g+1;
	
	case(g)
	0:begin
	//显示东西方向的时间十位
		case(shi_left)
			0:begin led_seg<=8'b11111100;end
			1:begin led_seg<=8'b01100000;end
			2:begin led_seg<=8'b11011010;end
			3:begin led_seg<=8'b11110010;end
			4:begin led_seg<=8'b01100110;end
		endcase
		led_dig<=8'b1101_1111;
	end
	
	1:begin
	//显示东西方向的时间个位
		case(ge_left)
			0:begin led_seg<=8'b11111100;end
			1:begin led_seg<=8'b01100000;end
			2:begin led_seg<=8'b11011010;end
			3:begin led_seg<=8'b11110010;end
			4:begin led_seg<=8'b01100110;end
			5:begin led_seg<=8'b10110110;end
			6:begin led_seg<=8'b00111110;end
			7:begin led_seg<=8'b11100000;end
			8:begin led_seg<=8'b11111110;end
			9:begin led_seg<=8'b11100110;end
		endcase
		led_dig<=8'b1110_1111;	
	end
	2:begin
	//显示南北方向的时间十位
		case(shi_right)
			0:begin led_seg<=8'b11111100;end
			1:begin led_seg<=8'b01100000;end
			2:begin led_seg<=8'b11011010;end
			3:begin led_seg<=8'b11110010;end
			4:begin led_seg<=8'b01100110;end
		endcase
		led_dig<=8'b1111_1101;
	end
		
	3:begin
	//显示南北方向的时间个位
		case(ge_right)
			0:begin led_seg<=8'b11111100;end
			1:begin led_seg<=8'b01100000;end
			2:begin led_seg<=8'b11011010;end
			3:begin led_seg<=8'b11110010;end
			4:begin led_seg<=8'b01100110;end
			5:begin led_seg<=8'b10110110;end
			6:begin led_seg<=8'b00111110;end
			7:begin led_seg<=8'b11100000;end
			8:begin led_seg<=8'b11111110;end
			9:begin led_seg<=8'b11100110;end
		endcase
		//指定时间的数码管
		led_dig<=8'b1111_1110;
	end
	endcase
end
//控制东西和南北方向指示灯变化的时间
always @(posedge clk)
begin
 if(reset==0)
begin
//东西方向为红灯时，南北方向为绿灯（南北方向倒记20秒时）
	if(seconds<20)
		begin
			led<=8'b1000_0010;
			state=24-seconds;
			shi_left<=state/10;
			ge_left<=state%10;
			
			state=19-seconds;
			shi_right<=state/10;
			ge_right<=state%10;
		end
//东西方向为红灯时，南北方向为黄灯（南北方向倒记5秒时）		
	if(seconds>19 && seconds<25)
		begin
			led<=8'b1000_0100;
			state=24-seconds;
			shi_left<=0;
			ge_left<=state%10;
			
			shi_right<=0;
			ge_right<=state%10;
		end
//东西方向为绿灯时，南北方向为红灯（东西方向倒记20秒时）		
	if(seconds>24 && seconds<45)
		begin
			led<=8'b0100_0001;
			state=44-seconds;
			shi_left<=state/10;
			ge_left<=state%10;
			
			state=49-seconds;
			shi_right<=state/10;
			ge_right<=state%10;
			
		end
//东西方向为黄灯时，南北方向为红灯（东西方向倒记5秒时）		
	if(seconds>44 && seconds<50)
		begin
			led<=8'b0010_0001;
			state=49-seconds;
			shi_left<=0;
			ge_left<=state%10;
			
			shi_right<=0;
			ge_right<=state%10;
		end
end
else
//紧急情况下，按reset（R16）键，东西南北方向均为红灯
	begin
		led<=8'b1000_0001;
	end

end		

endmodule