Verilog设计交通信号灯
目录
一、设计要求
二、模块总和
三、模块设计
1.顶层模块
2.分频模块
3.计数模块
4.状态机模块
5.倒计时模块
6.数码显示模块
7.约束代码
四、引脚分配
五、板上测试
总结
一、设计要求
1.利用 NEXYS4 DDR 开发板设计一款交通灯控制系统，能够显示红、黄、绿灯；
2.交通灯控制系统具有秒表倒计时功能；
3.我通过修改led六个分别表示主干道红绿黄和支干道红绿黄
4.信号灯设计时间
主干道绿灯，支干道红灯 30s
主干道红灯，支干道黄灯 5s
主干道红灯，支干道绿灯 30s
主干道黄灯，支干道红灯 5s
二、模块总和
三、模块设计
1.顶层模块
module top(
input clk,
input rst_n,
output [7:0]sel,
output [7:0]seg,
output [5:0]led
);
wire clk_1s;
wire [6:0]cnt;
wire [3:0]en1,en2;
div div(
.clk(clk),
.rst_n(rst_n),
.clk_1s(clk_1s)
);
counter counter(
.clk(clk_1s),
.rst_n(rst_n),
.cnt(cnt)
);
vlg_traffic a1(
.clk(clk),
.rst_n(rst_n),
.cnt(cnt),
.led(led)
);
countdown countdown(
.clk(clk),
.rst_n(rst_n),
.cnt(cnt),
.en1(en1),
.en2(en2)
);
digital digital(
.clk(clk),
.rst_n(rst_n),
.en1(en1),
.en2(en2),
.sel(sel),
.seg(seg)
);
endmodule2.分频模块
module div(
input clk,
input rst_n,
output reg clk_1s//1s
);
reg[29:0]count1;//计数1s
//1s计数
always @(posedge clk or negedge rst_n)
if(!rst_n)
count1 <= 1'b0;
else if(count1 == 49999999)//计数器1完成0.5s计数
count1 <= 1'b0;
else
count1 <= count1 + 1'b1;
//1s分频
always @(posedge clk or negedge rst_n)
if(!rst_n)
clk_1s <= 0;
else if(count1 == 49999999)
clk_1s <= ~clk_1s;//时钟100Mhz 完成1s分频
else
clk_1s <= clk_1s;
endmodule3.计数模块
module counter(
input clk,
input rst_n,
output reg [6:0]cnt//实现70s红绿黄灯
);
always @(posedge clk or negedge rst_n)
if(!rst_n)
cnt <= 0;
else if(cnt == 7'd70)
cnt <= 0;
else
cnt <= cnt + 1;
endmodule4.状态机模块
module vlg_traffic(
input clk,
input rst_n,
input [6:0]cnt,
output reg [5:0]led//led[5]主干道黄灯 led[4]主干道红灯 led[3]主干道绿灯
//led[2]支干道黄灯 led[1]支干道红灯 led[0]支干道绿灯
);
reg [3:0]state;
parameter s0 = 4'b00001;//s0:主干道绿灯，支干道红灯 30s 灯6'b001_010
parameter s1 = 4'b00010;//s1:主干道黄灯，支干道红灯 5s 灯6'b100_010
parameter s2 = 4'b00100;//s2:主干道红灯，支干道黄灯 5s 灯6'b010_100
parameter s3 = 4'b01000;//s3:主干道红灯，支干道绿灯 30s 灯6'b010_001
always @(posedge clk or negedge rst_n)
if(!rst_n)
state <= s0;
else case(state)
s0:begin
if(cnt <= 7'd29)
begin
led <= 6'b001_010;
state <= s0;
end
else
state <= s1;
end
s1:begin
if((cnt > 7'd29)&&(cnt <= 7'd34))//用于板上显示从5s倒计时
begin
led <= 6'b100_010;
state <= s1;
end
else
state <= s2;
end
s2:begin
if((cnt > 7'd34)&&(cnt <= 7'd39))
begin
led <= 6'b010_100;
state <= s2;
end
else
state <= s3;
end
s3:begin
if((cnt > 7'd39)&&(cnt <= 7'd69))
begin
led <= 6'b010_001;
state <= s3;
end
else
state <= s0;
end
default:state <= s0;
endcase
endmodule5.倒计时模块
module countdown(
input clk,
input rst_n,
input [6:0]cnt,
output reg [3:0]en1,// 个位 最多为9 位宽为4
output reg [3:0]en2 // 十位 最多为9 位宽为4
);
always @(posedge clk or negedge rst_n)
if(!rst_n)
begin
en1 <= 0;
en2 <= 0;
end
else if(cnt <= 7'd29)//用于板上从29s倒计时
begin
en1 <= (29-cnt)%10;
en2 <= ((29-cnt)-en1)/10;
end
else if((cnt > 7'd29)&&(cnt <= 7'd34))//板上从4s倒计时
begin
en1 <= (34-cnt);
en2 <= 0;
end
else if((cnt > 7'd34)&&(cnt <= 7'd39))//板上从4s倒计时
begin
en1 <= (39-cnt);
en2 <= 0;
end
else if((cnt > 7'd39)&&(cnt <= 7'd69))//板上从29s倒计时
begin
en1 <= (69-cnt)%10;
en2 <= ((69-cnt)-en1)/10;
end
endmodule 6.数码显示模块
module digital(
input clk,
input rst_n,
input [3:0]en1,
input [3:0]en2,
output reg [7:0]sel,//片选信号
output reg [7:0]seg //段选信号
);
//1ms计数器
reg [16:0]cnt1;
always @(posedge clk or negedge rst_n)
if(!rst_n)
cnt1 <= 0;
else if(cnt1 == 99999)//1000000/10=100000
cnt1 <= 0;
else
cnt1 <= cnt1 + 1;
//1ms使能时钟控制信号
reg clk_1ms;
always @(posedge clk or negedge rst_n)
if(!rst_n)
clk_1ms <= 0;
else if(cnt1 == 99999)
clk_1ms <= 1;
else
clk_1ms <= 0;
//位选计数器
reg [2:0]num_cnt;
always @(posedge clk or negedge rst_n)
if(!rst_n)
num_cnt <= 0;
else if(clk_1ms)
num_cnt <= num_cnt + 1;
//板上位选信号 共阳极 低电平有效
always @(posedge clk)
case(num_cnt)
0:sel <=8'b1111_1110;//个位
1:sel <=8'b1111_1101;//十位
2:sel <=8'b1111_1011;
3:sel <=8'b1111_0111;
4:sel <=8'b1110_1111;
5:sel <=8'b1101_1111;
6:sel <=8'b1011_1111;
7:sel <=8'b0111_1111;
endcase
//数据分配
wire [31:0]data;
assign data[3:0] = en1;
assign data[7:4] = en2;
assign data[11:8] = 0;
assign data[15:12] = 0;
assign data[19:16] = 0;
assign data[23:20] = 0;
assign data[27:24] = 0;
assign data[31:28] = 0;
reg [3:0]disp_tmp;
always @(posedge clk)
case(num_cnt)
0:disp_tmp <= data[3:0];
1:disp_tmp <= data[7:4];
2:disp_tmp <= data[11:8];
3:disp_tmp <= data[15:12];
4:disp_tmp <= data[19:16];
5:disp_tmp <= data[23:20];
6:disp_tmp <= data[27:24];
7:disp_tmp <= data[31:28];
endcase
//板上段选信号 共阳极 低电平有效
always @(posedge clk)
case(disp_tmp)
4'd0:seg <= 8'b1100_0000;
4'd1:seg <= 8'b1111_1001;
4'd2:seg <= 8'b1010_0100;
4'd3:seg <= 8'b1011_0000;
4'd4:seg <= 8'b1001_1001;
4'd5:seg <= 8'b1001_0010;
4'd6:seg <= 8'b1000_0010;
4'd7:seg <= 8'b1111_1000;
4'd8:seg <= 8'b1000_0000;
4'd9:seg <= 8'b1001_0000;
endcase
endmodule7.约束代码
set_property IOSTANDARD LVCMOS33 [get_ports {led[5]}]
set_property IOSTANDARD LVCMOS33 [get_ports {led[4]}]
set_property IOSTANDARD LVCMOS33 [get_ports {led[3]}]
set_property IOSTANDARD LVCMOS33 [get_ports {led[2]}]
set_property IOSTANDARD LVCMOS33 [get_ports {led[1]}]
set_property IOSTANDARD LVCMOS33 [get_ports {led[0]}]
set_property IOSTANDARD LVCMOS33 [get_ports {seg[7]}]
set_property IOSTANDARD LVCMOS33 [get_ports {seg[6]}]
set_property IOSTANDARD LVCMOS33 [get_ports {seg[5]}]
set_property IOSTANDARD LVCMOS33 [get_ports {seg[4]}]
set_property IOSTANDARD LVCMOS33 [get_ports {seg[3]}]
set_property IOSTANDARD LVCMOS33 [get_ports {seg[2]}]
set_property IOSTANDARD LVCMOS33 [get_ports {seg[1]}]
set_property IOSTANDARD LVCMOS33 [get_ports {seg[0]}]
set_property IOSTANDARD LVCMOS33 [get_ports {sel[7]}]
set_property IOSTANDARD LVCMOS33 [get_ports {sel[6]}]
set_property IOSTANDARD LVCMOS33 [get_ports {sel[5]}]
set_property IOSTANDARD LVCMOS33 [get_ports {sel[4]}]
set_property IOSTANDARD LVCMOS33 [get_ports {sel[3]}]
set_property IOSTANDARD LVCMOS33 [get_ports {sel[2]}]
set_property IOSTANDARD LVCMOS33 [get_ports {sel[1]}]
set_property IOSTANDARD LVCMOS33 [get_ports {sel[0]}]
set_property IOSTANDARD LVCMOS33 [get_ports clk]
set_property IOSTANDARD LVCMOS33 [get_ports rst_n]
set_property PACKAGE_PIN E3 [get_ports clk]
set_property PACKAGE_PIN C12 [get_ports rst_n]
set_property PACKAGE_PIN U13 [get_ports {sel[7]}]
set_property PACKAGE_PIN K2 [get_ports {sel[6]}]
set_property PACKAGE_PIN T14 [get_ports {sel[5]}]
set_property PACKAGE_PIN P14 [get_ports {sel[4]}]
set_property PACKAGE_PIN J14 [get_ports {sel[3]}]
set_property PACKAGE_PIN T9 [get_ports {sel[2]}]
set_property PACKAGE_PIN J18 [get_ports {sel[1]}]
set_property PACKAGE_PIN J17 [get_ports {sel[0]}]
set_property PACKAGE_PIN T10 [get_ports {seg[0]}]
set_property PACKAGE_PIN R10 [get_ports {seg[1]}]
set_property PACKAGE_PIN K16 [get_ports {seg[2]}]
set_property PACKAGE_PIN K13 [get_ports {seg[3]}]
set_property PACKAGE_PIN P15 [get_ports {seg[4]}]
set_property PACKAGE_PIN T11 [get_ports {seg[5]}]
set_property PACKAGE_PIN L18 [get_ports {seg[6]}]
set_property PACKAGE_PIN H15 [get_ports {seg[7]}]
set_property PACKAGE_PIN H17 [get_ports {led[0]}]
set_property PACKAGE_PIN K15 [get_ports {led[1]}]
set_property PACKAGE_PIN J13 [get_ports {led[2]}]
set_property PACKAGE_PIN N14 [get_ports {led[3]}]
set_property PACKAGE_PIN R18 [get_ports {led[4]}]
set_property PACKAGE_PIN V17 [get_ports {led[5]}]四、引脚分配
五、板上测试
S0:
S1:
S2:
S3:
总结
进行顶层模块时钟分配的时候，千万不能分配错，不然容易导致时间不一致导致数码显示错误；除了计数70s模块使用1s分频时钟，其余模块都是使用的原时钟信号，数码显示模块内部进行使用了1ms时钟使能，利用视觉暂留，进行数码管的动态扫描。