目录
一、设计要求
二、模块总和
三、模块设计
1.顶层模块
2.秒分频模块
3.秒计数模块
4.分钟分频模块
5.分钟计数模块
6.小时分频模块
7.小时计数模块
8.数据分配数码管模块
9.数码管显示模块
10.管脚约束代码
四、引脚分配
1.利用 NEXYS4 DDR 开发板设计一款数字时钟,能够正确显示时、分、秒;
2.数字时钟为24小时进制;
module digital_clock_top(
input clk,
input rst_n,
output [7:0]sel,
output [7:0]seg
);
wire clk_1s;
wire clk_1f;
wire clk_1h;
wire [5:0]cnt_s;
wire [5:0]cnt_f;
wire [4:0]cnt_h;
wire [3:0]bit_s;
wire [3:0]tenbit_s;
wire [3:0]bit_f;
wire [3:0]tenbit_f;
wire [3:0]bit_h;
wire [3:0]tenbit_h;
digital_clock_div_s a(
.clk(clk),
.rst_n(rst_n),
.clk_1s(clk_1s)
);
digital_clock_count_s b(
.clk(clk_1s),
.rst_n(rst_n),
.cnt_s(cnt_s)
);
digital_clock_div_f c(
.clk(clk),
.rst_n(rst_n),
.clk_1f(clk_1f)
);
digital_clock_count_f d(
.clk(clk_1f),
.rst_n(rst_n),
.cnt_f(cnt_f)
);
digital_clock_div_h e(
.clk(clk),
.rst_n(rst_n),
.clk_1h(clk_1h)
);
digital_clock_count_h f(
.clk(clk_1h),
.rst_n(rst_n),
.cnt_h(cnt_h)
);
digital_clock_time g(
.clk(clk),
.rst_n(rst_n),
.cnt_s(cnt_s),
.cnt_f(cnt_f),
.cnt_h(cnt_h),
.bit_s(bit_s),
.tenbit_s(tenbit_s),
.bit_f(bit_f),
.tenbit_f(tenbit_f),
.bit_h(bit_h),
.tenbit_h(tenbit_h)
);
digital_clock_digital h(
.clk(clk),
.rst_n(rst_n),
.bit_s(bit_s),
.tenbit_s(tenbit_s),
.bit_f(bit_f),
.tenbit_f(tenbit_f),
.bit_h(bit_h),
.tenbit_h(tenbit_h),
.sel(sel),
.seg(seg)
);
endmodule
module digital_clock_div_s(
input clk,
input rst_n,
output reg clk_1s
);
//计数器计数1s的数值
reg [25:0]cnt1;
always @(posedge clk or negedge rst_n)
if(!rst_n)
cnt1 <= 0;
else if(cnt1 == 26'd49999999)
cnt1 <= 0;
else
cnt1 <= cnt1 + 1;
//分频为1s
always @(posedge clk or negedge rst_n)
if(!rst_n)
clk_1s <= 0;
else if(cnt1 == 26'd49999999)
clk_1s <= ~clk_1s;
else
clk_1s <= clk_1s;
endmodule
module digital_clock_count_s(
input clk,
input rst_n,
output reg [5:0]cnt_s //计数60秒
);
always @(negedge clk or negedge rst_n)
if(!rst_n)
cnt_s <= 0;
else if(cnt_s == 6'd59)
cnt_s <= 0;
else
cnt_s <= cnt_s + 1;
endmodule
module digital_clock_div_f(
input clk,
input rst_n,
output reg clk_1f
);
//计数器计数1分钟的数值
reg [31:0]cnt2;//计数值 ((60000000000/10=6000000000)/2-1)=2,999,999,999
always @(posedge clk or negedge rst_n)
if(!rst_n)
cnt2 <= 0;
else if(cnt2 == 32'd2999999999)
cnt2 <= 0;
else
cnt2 <= cnt2 + 1;
//分频为1分钟
always @(posedge clk or negedge rst_n)
if(!rst_n)
clk_1f <= 0;
else if(cnt2 == 32'd2999999999)
clk_1f <= ~clk_1f;
else
clk_1f <= clk_1f;
endmodule
module digital_clock_count_f(
input clk,
input rst_n,
output reg [5:0]cnt_f //计数60分
);
always @(negedge clk or negedge rst_n)
if(!rst_n)
cnt_f <= 0;
else if(cnt_f == 6'd59)
cnt_f <= 0;
else
cnt_f <= cnt_f + 1;
endmodule
module digital_clock_div_h(
input clk,
input rst_n,
output reg clk_1h
);
//计数器计数1小时的数值
reg [37:0]cnt3;//计数值 ((3600000000000/10=360000000000)/2-1)=179,999,999,999
always @(posedge clk or negedge rst_n)
if(!rst_n)
cnt3 <= 0;
else if(cnt3 == 38'd179999999999)
cnt3 <= 0;
else
cnt3 <= cnt3 + 1;
//分频为1分钟
always @(posedge clk or negedge rst_n)
if(!rst_n)
clk_1h <= 0;
else if(cnt3 == 38'd179999999999)
clk_1h <= ~clk_1h;
else
clk_1h <= clk_1h;
endmodule
module digital_clock_count_h(
input clk,
input rst_n,
output reg [4:0]cnt_h //计数24小时
);
always @(negedge clk or negedge rst_n)
if(!rst_n)
cnt_h <= 0;
else if(cnt_h == 5'd23)
cnt_h <= 0;
else
cnt_h <= cnt_h + 1;
endmodule
module digital_clock_time(
input clk,
input rst_n,
input [5:0]cnt_s,
input [5:0]cnt_f,
input [4:0]cnt_h,
output reg [3:0]bit_s,//个位秒
output reg [3:0]tenbit_s,//十位秒
output reg [3:0]bit_f,//个位分
output reg [3:0]tenbit_f,//十位分
output reg [3:0]bit_h,//个位时
output reg [3:0]tenbit_h //十位时
);
always @(posedge clk or negedge rst_n )
if(!rst_n)
begin
bit_s <= 0;
tenbit_s <= 0;
end
else if (cnt_s < 6'd10)
begin
bit_s <= (cnt_s%10);
tenbit_s <= 0;
end
else if (cnt_s < 6'd20)
begin
bit_s <= (cnt_s - 10);
tenbit_s <= 1;
end
else if (cnt_s < 6'd30)
begin
bit_s <= (cnt_s - 20);
tenbit_s <= 2;
end
else if (cnt_s < 6'd40)
begin
bit_s <= (cnt_s - 30);
tenbit_s <= 3;
end
else if (cnt_s < 6'd50)
begin
bit_s <= (cnt_s - 40);
tenbit_s <= 4;
end
else if (cnt_s <= 6'd59)
begin
bit_s <= (cnt_s - 50);
tenbit_s <= 5;
end
always @(posedge clk or negedge rst_n )
if(!rst_n)
begin
bit_f <= 0;
tenbit_f <= 0;
end
else if (cnt_f < 6'd10)
begin
bit_f <= (cnt_f%10);
tenbit_f <= 0;
end
else if (cnt_f < 6'd20)
begin
bit_f <= (cnt_f - 10);
tenbit_f <= 1;
end
else if (cnt_f < 6'd30)
begin
bit_f <= (cnt_f - 20);
tenbit_f <= 2;
end
else if (cnt_f < 6'd40)
begin
bit_f <= (cnt_f - 30);
tenbit_f <= 3;
end
else if (cnt_f < 6'd50)
begin
bit_f <= (cnt_f - 40);
tenbit_f <= 4;
end
else if (cnt_f <= 6'd59)
begin
bit_f <= (cnt_f - 50);
tenbit_f <= 5;
end
always @(posedge clk or negedge rst_n )
if(!rst_n)
begin
bit_h <= 0;
tenbit_h <= 0;
end
else if (cnt_h < 5'd10)
begin
bit_h <= (cnt_h%10);
tenbit_h <= 0;
end
else if (cnt_h < 5'd20)
begin
bit_h <= (cnt_h - 10);
tenbit_h <= 1;
end
else if (cnt_h < 5'd23)
begin
bit_h <= (cnt_h - 20);
tenbit_h <= 2;
end
endmodule
module digital_clock_digital(
input clk,
input rst_n,
input [3:0]bit_s,//个位秒
input [3:0]tenbit_s,//十位秒
input [3:0]bit_f,//个位分
input [3:0]tenbit_f,//十位分
input [3:0]bit_h,//个位时
input [3:0]tenbit_h, //十位时
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]cnt4;
always @(posedge clk or negedge rst_n)
if(!rst_n)
cnt4 <= 0;
else if(cnt4 == 99999)//1000000/10=100000
cnt4 <= 0;
else
cnt4 <= cnt4 + 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(cnt4 == 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'b1111_1111;
7:sel <=8'b1111_1111;
endcase
//数据分配
wire [31:0]data;
assign data[3:0] = bit_s;
assign data[7:4] = tenbit_s;
assign data[11:8] = bit_f;
assign data[15:12] = tenbit_f;
assign data[19:16] = bit_h;
assign data[23:20] = tenbit_h;
/*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
endmodule
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 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 T10 [get_ports {seg[0]}]