这里我们要验证一键两用的情况：点击与长击，单击与双击
代码：
/********************************Copyright**************************************
**----------------------------File information--------------------------
** File name :key_function_2.v
** CreateDate :2015.03
** Funtions :按键的用法（二）：点击和长击，单击和双击
** Operate on :M5C06N3L114C7
** Copyright :All rights reserved.
** Version :V1.0
**---------------------------Modify the file information----------------
** Modified by :
** Modified data :
** Modify Content:
*******************************************************************************/ module key_function_2 (
clk,
rst_n, key_4,
key_5, led_d41,
led_d42,
led_d51,
led_d52 );
input clk;
input rst_n; input key_4; //按键的点击与长击：按下按键后，2S内松开按键则为点击，2s后松开按键为长击,默认未按下为高。
input key_5; /*按键的单击和双击，完成第一次按键后100ms之内第二次按下按键则为双击，否则为单击 */ output led_d41;
output led_d42;
output led_d51;
output led_d52; //---------------------------
//定时2s
reg cnt_en;
localparam t_1s = 'd23999999; /* //实际使用 */
// localparam t_1s = 25'd239; /* //测试使用 */ localparam t_2s = 'd2;
reg [:] cnt;
always @(posedge clk or negedge rst_n)
begin
if(!rst_n)
begin
cnt <= ;
end
else if(cnt_en)
begin
if(cnt == t_1s)
cnt <= ;
else
cnt <= cnt + ;
end
else
cnt <= ;
end reg [:] cnt1;
always @(posedge clk or negedge rst_n)
begin
if(!rst_n)
begin
cnt1 <= ;
end
else if(cnt_en)
begin
if(cnt1 == 'd2)
cnt1 <= 'd2;
else if(cnt == t_1s)
cnt1 <= cnt1 + ;
end
else
cnt1 <= ;
end //-------------------------------
/* 取key_4的上升沿和下降沿 */
reg [:] key_4_reg;
wire key_4_pos;
wire key_4_neg;
always @(posedge clk or negedge rst_n)
begin
if(!rst_n)
begin
key_4_reg <= 'b111;
end
else
begin
key_4_reg <= {key_4_reg[:],key_4};
end
end
assign key_4_pos = (key_4_reg[:] == 'b01);
assign key_4_neg = (key_4_reg[:] == 'b10); //------------------------------
/* 状态机 */
reg [:] state1;
reg key_S;
reg key_L;
always @(posedge clk or negedge rst_n)
begin
if(!rst_n)
begin
state1 <= 'd0;
cnt_en <= ;
key_S <= ;
key_L <= ;
end
else
begin
case(state1)
'd0:
begin
cnt_en <= ;
key_S <= ;
key_L <= ;
if(key_4_neg) /* 按键按下 */
state1 <= 'd1;
else
state1 <= 'd0;
end
'd1:
begin
if(key_4_pos) /* 按键释放 */
begin
cnt_en <= ;
state1 <= 'd2;
key_S <= ;
end
else if((key_4_reg=='b000)&&(cnt1 == 2'd2)) /* 按键一直为低，延时2s之后 */
begin
cnt_en <= ;
state1 <= 'd3;
key_L <= ;
end
else
cnt_en <= ;
end
'd2: /* 点击 */
begin
key_S <= ;
state1 <= 'd5;
end
'd3:
begin
key_L <= ;
state1 <= 'd4;
end
'd4:
begin
if(key_4_pos)
state1 <= 'd5;
else
state1 <= 'd4;
end
'd5:
begin
state1 <= 'd0;
end
default:state1 <= 'd0;
endcase end
end reg led_s;
reg led_l;
always @(posedge clk or negedge rst_n)
begin
if(!rst_n)
begin
led_s <= ;
end
else if(key_S)
begin
led_s <= ~led_s;
end
end always @(posedge clk or negedge rst_n)
begin
if(!rst_n)
begin
led_l <= ;
end
else if(key_L)
begin
led_l <= ~led_l;
end
end //------------------------------------
localparam t_100ms = 'd2399999; /* //实际使用 */
// localparam t_100ms = 22'd23; /* //测试使用 */
reg [:] cnnt;
reg cnnt_en;
always @(posedge clk or negedge rst_n)
begin
if(!rst_n)
begin
cnnt <= ;
end
else if(cnnt_en)
begin
if(cnnt == t_100ms )
cnnt <= t_100ms;
else
cnnt <= cnnt + ;
end
else
cnnt <= ;
end
//-------------------------------
/* 取key_5的上升沿和下降沿 */
reg [:] key_5_reg;
wire key_5_pos;
wire key_5_neg;
always @(posedge clk or negedge rst_n)
begin
if(!rst_n)
begin
key_5_reg <= 'b111;
end
else
begin
key_5_reg <= {key_5_reg[:],key_5};
end
end
assign key_5_pos = (key_5_reg[:] == 'b01);
assign key_5_neg = (key_5_reg[:] == 'b10); //------------------------------
/* 状态机 */
reg [:] state2;
reg key_SS;
reg key_D;
always @(posedge clk or negedge rst_n)
begin
if(!rst_n)
begin
state2 <= 'd0;
cnnt_en <= ;
key_SS <= ;
key_D <= ;
end
else
begin
case(state2)
'd0:
begin
cnnt_en <= ;
key_SS <= ;
key_D <= ;
if(key_5_neg) /*第一次 按键按下 */
state2 <= 'd1;
else
state2 <= 'd0;
end
'd1:
begin
if(key_5_pos) /*第一次 按键释放 */
begin
state2 <= 'd2;
end
else
state2 <= 'd1;
end
'd2:
begin
if((key_5_neg)&&(cnnt < t_100ms))
begin
cnnt_en <= ;
state2 <= 'd3;
key_D <= ;
end
else if(cnnt ==t_100ms)
begin
cnnt_en <= ;
state2 <= 'd4;
key_SS <= ;
end
else
cnnt_en <= ;
end
'd3:
begin
key_D <= ;
if(key_5_pos)
state2 <= 'd5;
end
'd4:
begin
key_SS <= ;
state2 <= 'd5;
end
'd5:
begin
state2 <= 'd0;
end
default:state2 <= 'd0;
endcase end
end reg led_signal;
reg led_double;
always @(posedge clk or negedge rst_n)
begin
if(!rst_n)
begin
led_signal <= ;
end
else if(key_SS)
begin
led_signal <= ~led_signal;
end
end always @(posedge clk or negedge rst_n)
begin
if(!rst_n)
begin
led_double <= ;
end
else if(key_D)
begin
led_double <= ~led_double;
end
end //------------------------
assign led_d41 = led_s;
assign led_d42 = led_l;
assign led_d51 = led_signal;
assign led_d52 = led_double; endmodule
仿真代码：
/********************************Copyright**************************************
**----------------------------File information--------------------------
** File name :key_function_testbench.v
** CreateDate :2015.03
** Funtions :按键功能的测试文件
** Operate on :M5C06N3L114C7
** Copyright :All rights reserved.
** Version :V1.0
**---------------------------Modify the file information----------------
** Modified by :
** Modified data :
** Modify Content:
*******************************************************************************/
`timescale ns/ ns module key_function_2_tb;
reg clk;
reg rst_n; reg key_4; //按键的点击与长击：按下按键后，2S内松开按键则为点击，2s后松开按键为长击,默认未按下为高。
reg key_5; /*按键的单击和双击，完成第一次按键后100ms之内第二次按下按键则为双击，否则为单击 */ wire led_d41;
wire led_d42;
wire led_d51;
wire led_d52; key_function_2 key_function_2(
.clk,
.rst_n, .key_4,
.key_5, .led_d41,
.led_d42,
.led_d51,
.led_d52 ); parameter tck = ;
parameter t = /tck; always #(t/) clk = ~clk; initial
begin
clk = ;
rst_n = ;
key_4 = ;
key_5 = ; #(*t) rst_n = ;
/* 点击 */
#(*t) key_4 = ;
#(*t) key_4 = ;
#(*t) key_4 = ; /* 长击 */
#(*t);
#(*t) key_4 = ;
#(*t) key_4 = ;
#(*t);
#(*t) key_4 = ; /* 单击 */
#(*t);
#(*t) key_5 = ;
#(*t) key_5 = ;
#(*t) key_5 = ; /* 双击 */
#(*t);
#(*t) key_5 = ;
#(*t) key_5 = ;
#(*t) key_5 = ;
#(*t) key_5 = ;
#(*t) key_5 = ;
#(*t) key_5 = ; end endmodule
仿真波形：
1、点击与长击
2、单击与双击
注：参考资料来自网络。