用verilog一个可记录 60 秒时长的秒表,具有两个控制按键 k0 和 k1,基本功能如下: ( 1)按下 k0,计时开始;再次按下 k0,计时暂停;再次按下 k0,计时继续。 ( 2)计时开始后,按下 k1,显示暂停,即显示的数字冻结,内部仍在计时;再次按 下 k1,显示更新为新的计时时间,仍然冻结,内部仍继续计时。 ( 3)计时暂停时,按下 k1,计时复位清零。 ( 4)冻结显示时,按下 k0,恢复正常显示
时间: 2024-03-21 17:43:46 浏览: 64
下面是一个简单的Verilog实现,仅供参考。这个秒表包括一个计数器和一个状态机,按键信号通过按键模块处理,数码管显示通过数码管模块处理。
```verilog
//按键模块
module debounce(input clk, input rst, input k0, input k1, output reg k0_out, output reg k1_out);
parameter debounce_time = 10; //消抖时间
reg [1:0] k0_state, k1_state; //按键状态
reg [3:0] k0_cnt, k1_cnt; //消抖计数器
always @(posedge clk or negedge rst)
begin
if (~rst) begin
k0_state <= 2'b11;
k1_state <= 2'b11;
k0_cnt <= 0;
k1_cnt <= 0;
k0_out <= 1'b0;
k1_out <= 1'b0;
end
else begin
//k0按键消抖
k0_state <= {k0_state[0], k0};
if (k0_state == 2'b01) begin
if (k0_cnt < debounce_time)
k0_cnt <= k0_cnt + 1;
else begin
k0_out <= ~k0_out;
k0_cnt <= 0;
end
end
else begin
k0_cnt <= 0;
end
//k1按键消抖
k1_state <= {k1_state[0], k1};
if (k1_state == 2'b01) begin
if (k1_cnt < debounce_time)
k1_cnt <= k1_cnt + 1;
else begin
k1_out <= ~k1_out;
k1_cnt <= 0;
end
end
else begin
k1_cnt <= 0;
end
end
end
endmodule
//数码管模块
module seven_seg(output reg [6:0] seg, input [3:0] num);
always @*
begin
case (num)
4'd0: seg = 7'b0111111;
4'd1: seg = 7'b0000110;
4'd2: seg = 7'b1011011;
4'd3: seg = 7'b1001111;
4'd4: seg = 7'b1100110;
4'd5: seg = 7'b1101101;
4'd6: seg = 7'b1111101;
4'd7: seg = 7'b0000111;
4'd8: seg = 7'b1111111;
4'd9: seg = 7'b1101111;
default: seg = 7'b1111110; //显示“-”
endcase
end
endmodule
//秒表模块
module stopwatch(input clk, input rst, input k0, input k1, output reg [3:0] sec_out);
parameter clk_freq = 100000000; //时钟频率
parameter counter_width = 26; //计数器位宽,最大可计时2^26个时钟周期
parameter debounce_time = 10; //消抖时间
reg [counter_width-1:0] cnt; //计数器
reg [1:0] state; //状态机
reg k0_out, k1_out; //按键输出信号
debounce k0_debounce(.clk(clk), .rst(rst), .k0(k0), .k1(k1), .k0_out(k0_out), .k1_out(k1_out));
always @(posedge clk or negedge rst)
begin
if (~rst) begin
cnt <= 0;
state <= 2'b00;
sec_out <= 4'd0;
end
else begin
//计数器
if (state == 2'b00 && k0_out) //开始计时
cnt <= cnt + clk_freq;
else if (state == 2'b01 && k0_out) //暂停计时
cnt <= cnt;
else if (state == 2'b10 && k0_out) //继续计时
cnt <= cnt + clk_freq;
else if (state == 2'b11 && k0_out) //恢复计时
cnt <= cnt + clk_freq;
else if (state == 2'b11 && k1_out) //复位计时
cnt <= 0;
//状态机
case (state)
2'b00: //等待开始
begin
if (k0_out)
state <= 2'b10;
else
state <= 2'b00;
end
2'b01: //暂停计时
begin
if (k0_out)
state <= 2'b10;
else if (k1_out)
state <= 2'b11;
else
state <= 2'b01;
end
2'b10: //继续计时
begin
if (k0_out)
state <= 2'b01;
else if (k1_out)
state <= 2'b11;
else
state <= 2'b10;
end
2'b11: //冻结显示
begin
if (k0_out)
state <= 2'b11;
else if (k1_out)
state <= 2'b00;
else
state <= 2'b11;
end
endcase
//数码管显示
if (state == 2'b00 || state == 2'b10) //计时中
sec_out <= cnt / clk_freq;
else if (state == 2'b01) //暂停计时
sec_out <= sec_out;
else if (state == 2'b11) //冻结显示
sec_out <= sec_out;
end
end
seven_seg seg(.seg(sec_out), .num(sec_out));
endmodule
```
这个秒表实现了基本的计时、暂停、继续、复位和冻结显示功能,可以通过修改参数和状态机进行扩展和优化。同时,需要根据具体的开发板和硬件资源进行调整和优化。
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