【黑金教程笔记之005】【建模篇】【Lab 04 消抖模块之二】—笔记

实验四和实验三的区别在于输出。实验三是检测到由高到低的电平变化时就拉高输出，检测到由低到高的电平变化时就拉低输出。而实验四检测到由高到低的电平变化时产生一个100ms的高脉冲。当检测到由低到高的电平变化时，只有消抖操做。

模块：

 1 /***********************************************************
 2 module name: detect_module.v
 3 function: detect pin's level change
 4 
 5 by yf.x
 6 2014-11-05
 7 
 8 ************************************************************/
 9 
10 module detect_module(
11 CLK,
12 RST_n,
13 Pin_in,
14 H2L_Sig,
15 L2H_Sig
16 );
17 
18 input CLK;
19 input RST_n;
20 input Pin_in;
21 output H2L_Sig;
22 output L2H_Sig;
23 
24 /**************************************************************/
25 //DE2-115 use 50MHz oscillator,50M*0.0001-1=4_999
26 parameter T100us=11'd4999;
27 
28 /**************************************************************/
29 
30 reg [10:0]count1;
31 reg isEn;
32 
33 always @(posedge CLK or negedge RST_n)    //100us timer
34 if(!RST_n)
35   begin
36     count1<=11'd0;
37      isEn<=1'b0;
38   end
39 else if(count1==T100us)
40   isEn<=1'b1;
41 else
42   count1<=count1+1'b1;
43   
44  /***********************************************************/
45 
46 reg H2L_F1;
47 reg H2L_F2;
48 reg L2H_F1;
49 reg L2H_F2;
50 
51 always @(posedge CLK or negedge RST_n)
52 if(!RST_n)
53   begin
54     H2L_F1<=1'b1;
55      H2L_F2<=1'b1;
56     L2H_F1<=1'b0;
57     L2H_F2<=1'b0;
58   end
59 else
60   begin
61     H2L_F1<=Pin_in;
62     H2L_F2<=H2L_F1;
63     L2H_F1<=Pin_in;
64     L2H_F2<=L2H_F1;
65   end
66 
67 /*****************************************************/
68 
69 assign H2L_Sig=isEn?(!H2L_F1&H2L_F2):1'b0;
70 assign L2H_Sig=isEn?(!L2H_F2&L2H_F1):1'b0;
71 
72 /*****************************************************/
73 
74 endmodule
75 
76   
77   

  1 /***************************************************
  2 module name: delay_module.v
  3 function: delay 10ms.
  4 
  5 by yf.x
  6 2014-11-05
  7 
  8 ***************************************************/
  9 
 10 module delay_module(
 11 CLK,
 12 RST_n,
 13 H2L_Sig,
 14 L2H_Sig,
 15 Pin_out
 16 );
 17 
 18 input CLK;
 19 input RST_n;
 20 input H2L_Sig;
 21 input L2H_Sig;
 22 output Pin_out;
 23 
 24 /**************************************************/
 25 //5M*0.001-1=49_999
 26 parameter T1ms=16'd49_999;
 27 
 28 /**************************************************/
 29 
 30 reg [15:0]count1;
 31 
 32 always @(posedge CLK or negedge RST_n)
 33 if(!RST_n)
 34   count1<=16'd0;
 35 else if(iscount && count1==T1ms)
 36   count1<=16'd0;
 37 else if(iscount)
 38   count1<=count1+1'b1;
 39 else if(!iscount)
 40   count1<=16'd0;
 41   
 42 /****************************************************/
 43 
 44 reg [6:0]count_ms;
 45 
 46 always @(posedge CLK or negedge RST_n)
 47 if(!RST_n)
 48   count_ms<=7'd0;
 49 else if(iscount && count1==T1ms)
 50   count_ms<=count_ms+1'b1;
 51 else if(!iscount)
 52   count_ms<=7'd0;
 53 
 54 /*******************************************************/
 55 
 56 reg iscount;
 57 reg rPin_out;
 58 reg [1:0]i;
 59 
 60 always @(posedge CLK or negedge RST_n)
 61 if(!RST_n)
 62   begin
 63     iscount<=1'b0;
 64     rPin_out<=1'b0;
 65     i<=2'd0;
 66   end
 67 else
 68   case(i)
 69     2'd0:
 70     if(H2L_Sig)
 71       i<=2'd1;
 72     else if(L2H_Sig)
 73        i<=2'd3;
 74         
 75      2'd1:
 76      if(count_ms==7'd10)
 77      begin 
 78        iscount<=1'b0;
 79        rPin_out<=1'b1;
 80        i<=2'd2;
 81      end
 82      else
 83        iscount<=1'b1;
 84         
 85      2'd2:
 86      if(count_ms==7'd100)
 87      begin
 88        iscount<=1'b0;
 89        rPin_out<=1'b0;
 90        i<=2'd0;
 91      end
 92      else
 93        iscount<=1'b1;
 94     
 95     2'd3:
 96      if(count_ms==7'd10)
 97      begin
 98        iscount<=1'b0;
 99        i<=2'd0;
100      end
101      else
102        iscount<=1'b1;
103     endcase
104 
105 /**************************************************/
106 
107 assign Pin_out=rPin_out;
108 
109 /**************************************************/
110 
111 endmodule
112     
113        
114   
115     

 1 /****************************************
 2 module name: debounce_module.v
 3 function: debounce a key
 4 pin assignments(for DE2-115):
 5 ---------------------------------
 6 CLK----------------------CLOCK_50
 7 RST_n--------------------KEY[0]
 8 Pin_in-------------------KEY[3]
 9 Pin_out------------------LEDG[3]
10 
11 by yf.x
12 2014-11-05
13 
14 ****************************************/
15 
16 module debounce_module(
17 CLK,
18 RST_n,
19 Pin_in,
20 Pin_out
21 );
22 
23 input CLK;
24 input RST_n;
25 input Pin_in;
26 output Pin_out;
27 
28 /*******************************/
29 
30 wire H2L_Sig;
31 wire L2H_Sig;
32 
33 detect_module u0(
34 .CLK(CLK),
35 .RST_n(RST_n),
36 .Pin_in(Pin_in),    //input from top
37 .H2L_Sig(H2L_Sig),  //output to u1
38 .L2H_Sig(L2H_Sig)   //output to u1
39 );
40 
41 /***************************************/
42 
43 delay_module u1(
44 .CLK(CLK),
45 .RST_n(RST_n),
46 .H2L_Sig(H2L_Sig),  //input from u1
47 .L2H_Sig(L2H_Sig),   //input from u1
48 .Pin_out(Pin_out)   //output to top
49 );
50 
51 /***************************************/
52 
53 endmodule

实验四说明：

实验四和实验三代码部分的区别在delay_module.v的case部分。