电子设计自动化实验相关

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本文内容基于电子设计自动化老师发的 实验报告模板

实验基于FPGA黑金开发平台AX301，此款开发板使用的是 ALTERA 公司的 Cyclone IV 系列 FPGA，型号为 EP4CE6F17C8

实验一：LED流水灯设计

codes

led_test.v

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`timescale 1ns / 1ps
module led_test
(
	input           clk,           // system clock 50Mhz on board
	input           rst_n,         // reset ,low active
	output reg[3:0] led            // LED,use for control the LED signal on board
);

//define the time counter
reg [31:0]      timer;

// cycle counter:from 0 to 4 sec
always@(posedge clk or negedge rst_n)
begin
	if (rst_n == 1'b0)
		timer <= 32'd0;                     //when the reset signal valid,time counter clearing
	else if (timer == 32'd199_999_999)      //4 seconds count(50M*4-1=199999999)
		timer <= 32'd0;                     //count done,clearing the time counter
	else
		timer <= timer + 32'd1;             //timer counter = timer counter + 1
end

// LED control
always@(posedge clk or negedge rst_n)
begin
	if (rst_n == 1'b0)
		led <= 4'b0000;                     //when the reset signal active
	else if (timer == 32'd49_999_999)       //time counter count to 1st sec,LED1 lighten
		led <= 4'b0001;
	else if (timer == 32'd99_999_999)       //time counter count to 2nd sec,LED2 lighten
		led <= 4'b0010;
	else if (timer == 32'd149_999_999)      //time counter count to 3rd sec,LED3 lighten
		led <= 4'b0100;
	else if (timer == 32'd199_999_999)      //time counter count to 4th sec,LED4 lighten
		led <= 4'b1000;
end
endmodule

实验二：数码管动态显示

codes

seg_test.v

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module seg_test(
                input      clk,
                input      rst_n,
                output[5:0]seg_sel,
                output[7:0]seg_data
                );
					 
reg[31:0] timer_cnt;
reg en_1hz;                          //1 second , 1 counter enable
always@(posedge clk or negedge rst_n)
begin
    if(rst_n == 1'b0)
    begin
        en_1hz <= 1'b0;
        timer_cnt <= 32'd0;
    end
    else if(timer_cnt >= 32'd49_999_999)
    begin
        en_1hz <= 1'b1;
        timer_cnt <= 32'd0;
    end
    else
    begin
        en_1hz <= 1'b0;
        timer_cnt <= timer_cnt + 32'd1; 
    end
end
wire[3:0] count0;
wire t0;
count_m10 count10_m0(
    .clk    (clk),
    .rst_n  (rst_n),
    .en     (en_1hz),
    .clr    (1'b0),
    .data   (count0),
    .t      (t0)
 );
wire[3:0] count1;
wire t1;
count_m6 count6_m1(	//oringin: count_m10 count10_m1
     .clk    (clk),
     .rst_n  (rst_n),
     .en     (t0),
     .clr    (1'b0),
     .data   (count1),
     .t      (t1)
 );

wire[3:0] count2;
wire t2;
count_m10 count10_m2(
    .clk   (clk),
    .rst_n (rst_n),
    .en    (t1),
    .clr   (1'b0),
    .data  (count2),
    .t     (t2)
);

wire[3:0] count3;
wire t3;
count_m10 count10_m3(
    .clk   (clk),
    .rst_n (rst_n),
    .en    (t2),
    .clr   (1'b0),
    .data  (count3),
    .t     (t3)
);

wire[3:0] count4;
wire t4;
count_m10 count10_m4(	
    .clk   (clk),
    .rst_n (rst_n),
    .en    (t3),
    .clr   (1'b0),
    .data  (count4),
    .t     (t4)
);

wire[3:0] count5;
wire t5;
count_m10 count10_m5(
    .clk   (clk),
    .rst_n (rst_n),
    .en    (t4),
    .clr   (1'b0),
    .data  (count5),
    .t     (t5)
);

wire[6:0] seg_data_0;
seg_decoder seg_decoder_m0(
    .bin_data  (count5),
    .seg_data  (seg_data_0)
);
wire[6:0] seg_data_1;
seg_decoder seg_decoder_m1(
    .bin_data  (count4),
    .seg_data  (seg_data_1)
);
wire[6:0] seg_data_2;
seg_decoder seg_decoder_m2(
    .bin_data  (count3),
    .seg_data  (seg_data_2)
);
wire[6:0] seg_data_3;
seg_decoder seg_decoder_m3(
    .bin_data  (count2),
    .seg_data  (seg_data_3)
);
wire[6:0] seg_data_4;
seg_decoder seg_decoder_m4(
    .bin_data  (count1),	//attention, this is COUNT1
    .seg_data  (seg_data_4)
);

wire[6:0] seg_data_5;
seg_decoder seg_decoder_m5(
    .bin_data  (count0),
    .seg_data  (seg_data_5)
);

seg_scan seg_scan_m0(
    .clk        (clk),
    .rst_n      (rst_n),
    .seg_sel    (seg_sel),
    .seg_data   (seg_data),
//    .seg_data_0 ({1'b1,seg_data_0}),      //The  decimal point at the highest bit,and low level effecitve
//    .seg_data_1 ({1'b1,seg_data_1}), 
//    .seg_data_2 ({1'b1,seg_data_2}),
//    .seg_data_3 ({1'b1,seg_data_3}),
    .seg_data_4 ({1'b1,seg_data_4}),
    .seg_data_5 ({1'b1,seg_data_5})
);
endmodule

seg_scan.v

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module seg_scan(
	input           clk,
	input           rst_n,
	output reg[5:0] seg_sel,      //digital led chip select
	output reg[7:0] seg_data,     //eight segment digital tube output,MSB is the decimal point
//	input[7:0]      seg_data_0,
//	input[7:0]      seg_data_1,
//	input[7:0]      seg_data_2,
//	input[7:0]      seg_data_3,
	input[7:0]      seg_data_4,
	input[7:0]      seg_data_5
);
parameter SCAN_FREQ = 200;     //scan frequency
parameter CLK_FREQ = 50000000; //clock frequency

parameter SCAN_COUNT = CLK_FREQ /(SCAN_FREQ * 6) - 1;

reg[31:0] scan_timer;  //scan time counter
reg[3:0] scan_sel;     //Scan select counter
always@(posedge clk or negedge rst_n)
begin
	if(rst_n == 1'b0)
	begin
		scan_timer <= 32'd0;
		scan_sel <= 4'd0;
	end
	else if(scan_timer >= SCAN_COUNT)
	begin
		scan_timer <= 32'd0;
		if(scan_sel == 4'd5)
			scan_sel <= 4'd0;
		else
			scan_sel <= scan_sel + 4'd1;
	end
	else
		begin
			scan_timer <= scan_timer + 32'd1;
		end
end
always@(posedge clk or negedge rst_n)
begin
	if(rst_n == 1'b0)
	begin
		seg_sel <= 6'b111111;
		seg_data <= 8'hff;
	end
	else
	begin
		case(scan_sel)
//			//first digital led
//			4'd0:
//			begin
//				seg_sel <= 6'b11_1110;
//				seg_data <= seg_data_0;
//			end
//			//second digital led
//			4'd1:
//			begin
//				seg_sel <= 6'b11_1101;
//				seg_data <= seg_data_1;
//			end
//			//...
//			4'd2:
//			begin
//				seg_sel <= 6'b11_1011;
//				seg_data <= seg_data_2;
//			end
//			4'd3:
//			begin
//				seg_sel <= 6'b11_0111;
//				seg_data <= seg_data_3;
//			end
			4'd4:
			begin
				seg_sel <= 6'b10_1111;
				seg_data <= seg_data_4;
			end
			4'd5:
			begin
				seg_sel <= 6'b01_1111;
				seg_data <= seg_data_5;
			end
			default:
			begin
				seg_sel <= 6'b11_1111;
				seg_data <= 8'hff;
			end
		endcase
	end
end

endmodule

count_m10.v

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module count_m10(
                 input          clk,
                 input          rst_n,
                 input          en,    //Counter enable
                 input          clr,   //Counter synchronous reset   
                 output reg[3:0]data,  //counter value
                 output reg     t      // carry enable signal
                );
always@(posedge clk or negedge rst_n) 
begin
    if(rst_n==0)
    begin
        data <= 4'd0;
        t <= 1'd0;
    end
    else if(clr)
    begin
        data <= 4'd0;
        t <= 1'd0;      
    end
    else if(en)
    begin
        if(data==4'd9)
        begin
            t<= 1'b1;    //Counter to 9 to generate carry
            data <= 4'd0;//Counter to 9 reset
        end
        else
        begin
            t <= 1'b0;
            data <= data + 4'd1;
        end
    end
    else
        t <= 1'b0;
end

endmodule

count_m6.v

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module count_m6(
                 input          clk,
                 input          rst_n,
                 input          en,    //Counter enable
                 input          clr,   //Counter synchronous reset   
                 output reg[3:0]data,  //counter value
                 output reg     t      // carry enable signal
                );
always@(posedge clk or negedge rst_n) 
begin
    if(rst_n==0)
    begin
        data <= 4'd0;
        t <= 1'd0;
    end
    else if(clr)
    begin
        data <= 4'd0;
        t <= 1'd0;      
    end
    else if(en)
    begin
        if(data==4'd5)
        begin
            t<= 1'b1;    //Counter to 5 to generate carry
            data <= 4'd0;//Counter to 5 reset
        end
        else
        begin
            t <= 1'b0;
            data <= data + 4'd1;
        end
    end
    else
        t <= 1'b0;
end

endmodule

seg_decoder.v

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module seg_decoder
(
	input[3:0]      bin_data,     // bin data input
	output reg[6:0] seg_data      // seven segments LED output  //origin: [6:0]
);

always@(*)
begin
	case(bin_data)
		4'd0:seg_data <= 7'b100_0000;
		4'd1:seg_data <= 7'b111_1001;
		4'd2:seg_data <= 7'b010_0100;
		4'd3:seg_data <= 7'b011_0000;
		4'd4:seg_data <= 7'b001_1001;
		4'd5:seg_data <= 7'b001_0010;
		4'd6:seg_data <= 7'b000_0010;
		4'd7:seg_data <= 7'b111_1000;
		4'd8:seg_data <= 7'b000_0000;
		4'd9:seg_data <= 7'b001_0000;
		4'ha:seg_data <= 7'b000_1000;
		4'hb:seg_data <= 7'b000_0011;
		4'hc:seg_data <= 7'b100_0110;
		4'hd:seg_data <= 7'b010_0001;
		4'he:seg_data <= 7'b000_0110;
		4'hf:seg_data <= 7'b000_1110;
		default:seg_data <= 7'b111_1111;
	endcase
end
endmodule

实验三 数字时钟（计数器）

codes

在实验二代码的基础上，把前边代码中注释掉的部分取消注释，然后添加下边两个：

count_m24_x.v

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module count_m24_x(
                 input          clk,
                 input          rst_n,
                 input          en,    //Counter enable
                 input          clr,   //Counter synchronous reset   
                 output reg[3:0]data,  //counter value
                 output reg     t      // carry enable signal
                );
always@(posedge clk or negedge rst_n) 
begin
    if(rst_n==0)
    begin
        data <= 4'd0;
        t <= 1'd0;
    end
    else if(clr)
    begin
        data <= 4'd0;
        t <= 1'd0;      
    end
    else if(en)
    begin
        if(data==4'd2)
        begin
            t<= 1'b1;    //Counter to 2 to generate carry
            data <= 4'd0;//Counter to 2 reset
        end
        else
        begin
            t <= 1'b0;
            data <= data + 4'd1;
        end
    end
    else
        t <= 1'b0;
end

endmodule

count_m24_y.v

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module count_m24_y(
                 input          clk,
                 input          rst_n,
                 input          en,    //Counter enable
                 input          clr,   //Counter synchronous reset   
                 output reg[3:0]data,  //counter value
                 output reg     t      // carry enable signal
                );
					 
reg[3:0] y_timer;	// 24_y timer

always@(posedge clk or negedge rst_n)
begin
    if(rst_n==0)
    begin
        data <= 4'd0;
        t <= 1'd0;
		  y_timer <= 4'd0;
    end
    else if(clr)
    begin
        data <= 4'd0;
        t <= 1'd0;
		  y_timer <= 4'd0;		  
    end
    else if(en)
    begin
        if(data==4'd9)
        begin
            t<= 1'b1;    //Counter to 9 to generate carry
            data <= 4'd0;//Counter to 9 reset
				y_timer <= y_timer + 4'd1;	
        end
		  else if(data==4'd3 && y_timer==4'd2)
		  begin
				t <= 1'b1;
				data <= 4'd0;
				y_timer <= 4'd0;
			end
        else
        begin
            t <= 1'b0;
            data <= data + 4'd1;
        end
    end
    else
        t <= 1'b0;
end

endmodule

然后，在seg_test.v里边，第89行的wire t3的count_m10改成count_m6，然后把第100行和111行的wire t4和wire t5的count_m10分别改为count_m24_y和count_m24_x即可实现。

另外，如果需要加快时钟的速度，可以修改seg_test.v第45行的32'd49_999_999为32'd49_999，这样分钟的十位会按比秒稍微快一点的速度计数。

实验四：正弦信号发生器设计

codes

sinwave1.v

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module sinwave1(clk,rst_n,dout);
input clk,rst_n;
output [7:0] dout;
reg[7:0] address;
reg rden;
always@(posedge clk or negedge rst_n)
begin
	if (!rst_n)
		rden<=0;
	else
		rden<=1;
end
always@(posedge clk or negedge rst_n)
begin
	if (!rst_n)
		address<=0;
	else
		address<=address+1;
end
myrom1 u1(.address(address),.clock(clk),.rden(rden),.q(dout));
endmodule

实验五：任意波形发生器设计

codes

hechengbo.v

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module hechengbo(
	input clk,
	input rst,
	output [7:0] q1,
	output [7:0] q2, 
	output [7:0] q3, 
	output [7:0] q4, 
	output [8:0] q5, 
	output [8:0] q6, 
	output [8:0] q7, 
	output [8:0] q8, 
	output [8:0] q9, 
	output [8:0] q10,
	output [9:0] q11,
	output [9:0] q12, 
	output [9:0] q13, 
	output [9:0] q14, 
	output [10:0] q15 
);

reg [8:0] address;

	always @ (negedge clk or negedge rst)
begin
	if(!rst)
		address <= 1'b0;
	else
		address <= address+1'b1;
end
sinewave		ROM_1
(
 .address(address),
 .clock (clk),
 .q (q1)
);
fangbo		ROM_2
(
 .address(address),
 .clock (clk),
 .q (q2)
);
jvchibo		ROM_3
(
 .address(address),
 .clock (clk),
 .q (q3)
);
sanjiaobo	ROM_4
(
 .address(address),
 .clock (clk),
 .q (q4)
);
assign q5=q1+q2;
assign q6=q1+q3;
assign q7=q1+q4;
assign q8=q3+q2;
assign q9=q4+q2;
assign q10=q1+q3+q4;
assign q11=q1+q2+q3;
assign q12=q1+q2+q4;
assign q13=q2+q3+q4;
assign q14=q3+q4;
assign q15=q1+q2+q3+q4;

endmodule

实验六：硬件消抖电路设计

codes

seg_scan.v

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module seg_scan(
	input           clk,
	input           rst_n,
	output reg[5:0] seg_sel,      //digital led chip select
	output reg[7:0] seg_data,     //eight segment digital tube output,MSB is the decimal point
	input[7:0]      seg_data_0,
	input[7:0]      seg_data_1,
	input[7:0]      seg_data_2,
	input[7:0]      seg_data_3,
	input[7:0]      seg_data_4,
	input[7:0]      seg_data_5
);
parameter SCAN_FREQ = 200;     //scan frequency
parameter CLK_FREQ = 50000000; //clock frequency

parameter SCAN_COUNT = CLK_FREQ /(SCAN_FREQ * 6) - 1;

reg[31:0] scan_timer;  //scan time counter
reg[3:0] scan_sel;     //Scan select counter
always@(posedge clk or negedge rst_n)
begin
	if(rst_n == 1'b0)
	begin
		scan_timer <= 32'd0;
		scan_sel <= 4'd0;
	end
	else if(scan_timer >= SCAN_COUNT)
	begin
		scan_timer <= 32'd0;
		if(scan_sel == 4'd5)
			scan_sel <= 4'd0;
		else
			scan_sel <= scan_sel + 4'd1;
	end
	else
		begin
			scan_timer <= scan_timer + 32'd1;
		end
end
always@(posedge clk or negedge rst_n)
begin
	if(rst_n == 1'b0)
	begin
		seg_sel <= 6'b111111;
		seg_data <= 8'hff;
	end
	else
	begin
		case(scan_sel)
			//first digital led
			4'd0:
			begin
				seg_sel <= 6'b11_1110;
				seg_data <= seg_data_0;
			end
			//second digital led
			4'd1:
			begin
				seg_sel <= 6'b11_1101;
				seg_data <= seg_data_1;
			end
			//...
			4'd2:
			begin
				seg_sel <= 6'b11_1011;
				seg_data <= seg_data_2;
			end
			4'd3:
			begin
				seg_sel <= 6'b11_0111;
				seg_data <= seg_data_3;
			end
			4'd4:
			begin
				seg_sel <= 6'b10_1111;
				seg_data <= seg_data_4;
			end
			4'd5:
			begin
				seg_sel <= 6'b01_1111;
				seg_data <= seg_data_5;
			end
			default:
			begin
				seg_sel <= 6'b11_1111;
				seg_data <= 8'hff;
			end
		endcase
	end
end

endmodule

seg_decoder.v

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module seg_decoder
(
	input[3:0]      bin_data,     // bin data input
	output reg[6:0] seg_data      // seven segments LED output
);

always@(*)
begin
	case(bin_data)
		4'd0:seg_data <= 7'b100_0000;
		4'd1:seg_data <= 7'b111_1001;
		4'd2:seg_data <= 7'b010_0100;
		4'd3:seg_data <= 7'b011_0000;
		4'd4:seg_data <= 7'b001_1001;
		4'd5:seg_data <= 7'b001_0010;
		4'd6:seg_data <= 7'b000_0010;
		4'd7:seg_data <= 7'b111_1000;
		4'd8:seg_data <= 7'b000_0000;
		4'd9:seg_data <= 7'b001_0000;
		4'ha:seg_data <= 7'b000_1000;
		4'hb:seg_data <= 7'b000_0011;
		4'hc:seg_data <= 7'b100_0110;
		4'hd:seg_data <= 7'b010_0001;
		4'he:seg_data <= 7'b000_0110;
		4'hf:seg_data <= 7'b000_1110;
		default:seg_data <= 7'b111_1111;
	endcase
end
endmodule

key_debounce.v

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module key_debounce(
    input        clk,
    input        rst_n,
	input        key1,
    output [5:0] seg_sel,
    output [7:0] seg_data
);
wire button_negedge; //Key falling edge
ax_debounce ax_debounce_m0
(
    .clk             (clk),
    .rst             (~rst_n),
    .button_in       (key1),
    .button_posedge  (),
    .button_negedge  (button_negedge),
    .button_out      ()
);

wire[3:0] count;
wire t0;
count_m10 count10_m0(
    .clk    (clk),
    .rst_n  (rst_n),
    .en     (button_negedge),
    .clr    (1'b0),
    .data   (count),
    .t      (t0)
);
wire[3:0] count1;
wire t1;
count_m6 count10_m1(
    .clk    (clk),
    .rst_n  (rst_n),
    .en     (t0),
    .clr    (1'b0),
    .data   (count1),
    .t      (t1)
);
//Count decoding
wire[6:0] seg_data_0;
seg_decoder seg_decoder_m0(
    .bin_data  (count),
    .seg_data  (seg_data_0)
);

wire[6:0] seg_data_1;
seg_decoder seg_decoder_m1(
    .bin_data  (count1),
    .seg_data  (seg_data_1)
);
seg_scan seg_scan_m0(
    .clk        (clk),
    .rst_n      (rst_n),
    .seg_sel    (seg_sel),
    .seg_data   (seg_data),
    .seg_data_0 ({1'b1,7'b1111_111}),
    .seg_data_1 ({1'b1,7'b1111_111}),
    .seg_data_2 ({1'b1,7'b1111_111}),
    .seg_data_3 ({1'b1,7'b1111_111}),
    .seg_data_4 ({1'b1,seg_data_1}),
    .seg_data_5 ({1'b1,seg_data_0})
);
endmodule

count_m10.v

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module count_m10(
                 input          clk,
                 input          rst_n,
                 input          en,    //Counter enable
                 input          clr,   //Counter synchronous reset   
                 output reg[3:0]data,  //counter value
                 output reg     t      // carry enable signal
                );
always@(posedge clk or negedge rst_n) 
begin
    if(rst_n==0)
    begin
        data <= 4'd0;
        t <= 1'd0;
    end
    else if(clr)
    begin
        data <= 4'd0;
        t <= 1'd0;      
    end
    else if(en)
    begin
        if(data==4'd9)
        begin
            t<= 1'b1;    //Counter to 9 to generate carry
            data <= 4'd0;//Counter to 9 reset
        end
        else
        begin
            t <= 1'b0;
            data <= data + 4'd1;
        end
    end
    else
        t <= 1'b0;
end

endmodule

ax_debounce.v

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`timescale 1 ns / 100 ps
module  ax_debounce 
(
    input       clk, 
    input       rst, 
    input       button_in,
    output reg  button_posedge,
    output reg  button_negedge,
    output reg  button_out
);
//// ---------------- internal constants --------------
parameter N = 32 ;           // debounce timer bitwidth
parameter FREQ = 50;         //model clock :Mhz
parameter MAX_TIME = 20;     //ms
localparam TIMER_MAX_VAL =   MAX_TIME * 1000 * FREQ;
////---------------- internal variables ---------------
reg  [N-1 : 0]  q_reg;      // timing regs
reg  [N-1 : 0]  q_next;
reg DFF1, DFF2;             // input flip-flops
wire q_add;                 // control flags
wire q_reset;
reg button_out_d0;
//// ------------------------------------------------------

////contenious assignment for counter control
assign q_reset = (DFF1  ^ DFF2);          // xor input flip flops to look for level chage to reset counter
assign q_add = ~(q_reg == TIMER_MAX_VAL); // add to counter when q_reg msb is equal to 0
    
//// combo counter to manage q_next 
always @ ( q_reset, q_add, q_reg)
begin
    case( {q_reset , q_add})
        2'b00 :
                q_next <= q_reg;
        2'b01 :
                q_next <= q_reg + 1;
        default :
                q_next <= { N {1'b0} };
    endcase     
end

//// Flip flop inputs and q_reg update
always @ ( posedge clk or posedge rst)
begin
    if(rst == 1'b1)
    begin
        DFF1 <= 1'b0;
        DFF2 <= 1'b0;
        q_reg <= { N {1'b0} };
    end
    else
    begin
        DFF1 <= button_in;
        DFF2 <= DFF1;
        q_reg <= q_next;
    end
end

//// counter control
always @ ( posedge clk or posedge rst)
begin
	if(rst == 1'b1)
		button_out <= 1'b1;
    else if(q_reg == TIMER_MAX_VAL)
        button_out <= DFF2;
    else
        button_out <= button_out;
end

always @ ( posedge clk or posedge rst)
begin
	if(rst == 1'b1)
	begin
		button_out_d0 <= 1'b1;
		button_posedge <= 1'b0;
		button_negedge <= 1'b0;
	end
	else
	begin
		button_out_d0 <= button_out;
		button_posedge <= ~button_out_d0 & button_out;
		button_negedge <= button_out_d0 & ~button_out;
	end	
end
endmodule

count_m6.v

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module count_m6(
                 input          clk,
                 input          rst_n,
                 input          en,    //Counter enable
                 input          clr,   //Counter synchronous reset   
                 output reg[3:0]data,  //counter value
                 output reg     t      // carry enable signal
                );
always@(posedge clk or negedge rst_n) 
begin
    if(rst_n==0)
    begin
        data <= 4'd0;
        t <= 1'd0;
    end
    else if(clr)
    begin
        data <= 4'd0;
        t <= 1'd0;      
    end
    else if(en)
    begin
        if(data==4'd5)
        begin
            t<= 1'b1;    //Counter to 5 to generate carry
            data <= 4'd0;//Counter to 5 reset
        end
        else
        begin
            t <= 1'b0;
            data <= data + 4'd1;
        end
    end
    else
        t <= 1'b0;
end

endmodule
≡