基于Verilog的按键检测实验

一、模块框图及基本思路

detect_module:检测按键输入脚的电平边沿变化

delay_10ms_module:延时消抖，输出按键有效信号

debounce_module:前两个模块的组合模块

key_control:按键信号控制Led

key_demo:顶层模块

二、软件部分

detect_module.v

 1 module detect_module(
 2     CLK,RSTn,
 3     Key_Pin_In,
 4     H2L_Sig,L2H_Sig
 5     );
 6     input CLK,RSTn;
 7     input Key_Pin_In;
 8     output H2L_Sig,L2H_Sig;
 9     
10     /****************************************************/
11     localparam T100us=50_000_000/1_000_000*100-1;
12     reg [15:0] Count_100us;
13     reg isEn;
14     
15     always @(posedge CLK or negedge RSTn)
16     begin
17         if(!RSTn)
18         begin
19             Count_100us<=16'd0;
20             isEn<=1'b0;
21         end
22         else if(Count_100us==T100us)
23             isEn<=1'b1;
24         else Count_100us<=Count_100us+1'b1;
25     end
26     
27     /****************************************************/
28     reg H2L_Sig_r1,H2L_Sig_r2;
29     reg L2H_Sig_r1,L2H_Sig_r2;
30     always @(posedge CLK or negedge RSTn)
31     begin
32         if(!RSTn)
33         begin
34             H2L_Sig_r1<=1'b1;
35             H2L_Sig_r2<=1'b1;
36             L2H_Sig_r1<=1'b0;
37             L2H_Sig_r2<=1'b0;
38         end
39         else 
40         begin
41             H2L_Sig_r1<=Key_Pin_In;
42             H2L_Sig_r2<=H2L_Sig_r1;
43             L2H_Sig_r1<=Key_Pin_In;
44             L2H_Sig_r2<=L2H_Sig_r1;
45         end
46     end
47     
48     /****************************************************/
49     
50     assign H2L_Sig=isEn?(H2L_Sig_

delay_10ms_module.v

 1 module delay10ms_module(
 2     CLK,RSTn,
 3     H2L_Sig,L2H_Sig,
 4     Key_Sig_Out
 5     );
 6      input CLK,RSTn;
 7      input H2L_Sig,L2H_Sig;
 8      output Key_Sig_Out;
 9      
10      /**********************************************/
11      localparam T10ms=50_000_000/1000*10-1;
12      reg[31:0] Count_10ms;
13      reg isCount;
14      always @(posedge CLK or negedge RSTn)
15      begin
16         if(!RSTn)
17         begin
18             Count_10ms<=32'd0;
19         end
20         else if(Count_10ms==T10ms) Count_10ms<=32'd0;
21         else if(isCount) Count_10ms<=Count_10ms+1'b1;
22      end
23      
24      /**********************************************/
25      reg Key_Sig_Out_r;
26      reg [1:0]i;
27      always @(posedge CLK or negedge RSTn)
28      begin
29         if(!RSTn)
30         begin
31             Key_Sig_Out_r<=0;
32             i<=0;
33             isCount<=1'b0;
34         end
35         else
36             case(i)
37                 2'd0:if(H2L_Sig) i<=2'd1;
38                         else if(L2H_Sig) i<=2'd2;
39                 2'd1:if(Count_10ms==T10ms) begin Key_Sig_Out_r<=1'b1;isCount<=1'b0;i<=2'd0;end
40                         else isCount<=1'b1;
41                 2'd2:if(Count_10ms==T10ms) begin Key_Sig_Out_r<=1'b0;isCount<=1'b0;i<=2'd0;end
42                         else isCount<=1'b1;
43             
44             endcase
45      end
46      /***************************************************/
47     assign Key_Sig_Out=Key_Sig_Out_r;
48 
49 endmodule

debounce_module.v

 1 module debounce_module(
 2     CLK,RSTn,
 3     Key_Pin_In,
 4     Key_Sig_Out
 5     );
 6      input CLK,RSTn;
 7      input Key_Pin_In;
 8      output Key_Sig_Out;
 9      
10     wire H2L_Sig;
11     wire L2H_Sig;
12      
13     detect_module U0(
14         .CLK(CLK), 
15         .RSTn(RSTn), 
16         .Key_Pin_In(Key_Pin_In), 
17         .H2L_Sig(H2L_Sig), 
18         .L2H_Sig(L2H_Sig)
19     );
20     delay10ms_module U1(
21         .CLK(CLK), 
22         .RSTn(RSTn), 
23         .H2L_Sig(H2L_Sig), 
24         .L2H_Sig(L2H_Sig), 
25         .Key_Sig_Out(Key_Sig_Out)
26     );
27 
28 
29 endmodule

key_control.v

 1 module key_control(
 2     CLK,RSTn,
 3     Key_Sig,
 4     Led
 5     );
 6      input CLK,RSTn;
 7      input Key_Sig;
 8      output Led;
 9      
10      /***********************************/
11      reg Key_Sig_r1,Key_Sig_r2;
12      wire Led_Sig;
13      always @(posedge CLK or negedge RSTn)
14      begin
15         if(!RSTn)
16         begin
17             Key_Sig_r1<=1'b0;
18             Key_Sig_r2<=1'b0;
19         end
20         else 
21         begin
22             Key_Sig_r1<=Key_Sig;
23             Key_Sig_r2<=Key_Sig_r1;
24         end
25      end
26      assign Led_Sig=Key_Sig_r1&!Key_Sig_r2;
27      /************************************/
28      reg rLed;
29      always @(posedge CLK or negedge RSTn )
30      begin
31          if(!RSTn) rLed<=1'b0;
32          else if(Led_Sig) rLed<=~rLed;
33      end
34     assign Led=rLed;
35 endmodule

key_demo.v

 1 module key_demo(
 2     CLK,RSTn,
 3     Key_Pin_In,Led
 4     );
 5      input CLK,RSTn;
 6      input [3:0]Key_Pin_In;
 7      output [3:0]Led;
 8      
 9     wire Key_Sig1;
10     key_control U0 (
11         .CLK(CLK), 
12         .RSTn(RSTn), 
13         .Key_Sig(Key_Sig1), 
14         .Led(Led[0])
15     );
16     debounce_module U1 (
17         .CLK(CLK), 
18         .RSTn(RSTn), 
19         .Key_Pin_In(Key_Pin_In[0]), 
20         .Key_Sig_Out(Key_Sig1)
21     );
22     
23     wire Key_Sig2;
24     key_control U2 (
25         .CLK(CLK), 
26         .RSTn(RSTn), 
27         .Key_Sig(Key_Sig2), 
28         .Led(Led[1])
29     );
30     debounce_module U3 (
31         .CLK(CLK), 
32         .RSTn(RSTn), 
33         .Key_Pin_In(Key_Pin_In[1]), 
34         .Key_Sig_Out(Key_Sig2)
35     );
36     
37    wire Key_Sig3;
38     key_control U4 (
39         .CLK(CLK), 
40         .RSTn(RSTn), 
41         .Key_Sig(Key_Sig3), 
42         .Led(Led[2])
43     );
44     debounce_module U5 (
45         .CLK(CLK), 
46         .RSTn(RSTn), 
47         .Key_Pin_In(Key_Pin_In[2]), 
48         .Key_Sig_Out(Key_Sig3)
49     );
50     
51     wire Key_Sig4;
52     key_control U6 (
53         .CLK(CLK), 
54         .RSTn(RSTn), 
55         .Key_Sig(Key_Sig4), 
56         .Led(Led[3])
57     );
58     debounce_module U7 (
59         .CLK(CLK), 
60         .RSTn(RSTn), 
61         .Key_Pin_In(Key_Pin_In[3]), 
62         .Key_Sig_Out(Key_Sig4)
63     );
64     
65 endmodule

三、硬件部分

黑金SPARTAN-6开发板

 1 NET "CLK" LOC = T8;
 2 NET "RSTn" LOC = L3;
 3 
 4 NET "Led[0]" LOC = P4;
 5 NET "Led[1]" LOC = N5;
 6 NET "Led[2]" LOC = P5;
 7 NET "Led[3]" LOC = M6;
 8 
 9 NET "Key_Pin_In[0]" LOC = C3;
10 NET "Key_Pin_In[1]" LOC = D3;
11 NET "Key_Pin_In[2]" LOC = E4;
12 NET "Key_Pin_In[3]" LOC = E3;