牛客网刷题4

25-28

25题

输入序列连续的序列检测_牛客题霸_牛客网 (nowcoder.com)

`timescale 1ns/1ns
module sequence_detect(
	input clk,
	input rst_n,
	input a,
	output reg match
	);

reg [8:0] tmp;
//存储
always @(posedge clk or negedge rst_n) begin
    if (!rst_n) begin
        tmp <= 0;
    end
    else  begin
        tmp <= {tmp[7:0],a};
    end
end


always @(posedge clk or negedge rst_n) begin
    if (!rst_n) begin
        match <= 0;
    end 
    else if (tmp == 9'b01110001) begin
        match <= 1;
    end
    else begin
        match <= 0;
    end
end
  
endmodule

26题

含有无关项的序列检测_牛客题霸_牛客网 (nowcoder.com)

`timescale 1ns/1ns
module sequence_detect(
	input clk,
	input rst_n,
	input a,
	output reg match
	);

  reg [8:0] tmp;
//存储
always @(posedge clk or negedge rst_n) begin
    if (!rst_n) begin
        tmp <= 0;
    end
    else  begin
        tmp <= {tmp[7:0],a};
    end
end

wire flag;
always @(posedge clk or negedge rst_n) begin
    if (!rst_n) begin
        match <= 0;
    end 
    else if (flag) begin
        match <= 1;
    end
    else begin
        match <= 0;
    end
end

assign flag = tmp[8:6] == 3'b011 && tmp[2:0] == 3'b110;
endmodule

27题

不重叠序列检测_牛客题霸_牛客网 (nowcoder.com)

`timescale 1ns/1ns
module sequence_detect(
	input clk,
	input rst_n,
	input data,
	output reg match,
	output reg not_match
	);


    //计数器
    reg [2:0] cnt;
    always @(posedge clk or negedge rst_n) begin
       if (!rst_n) begin
            cnt <= 0;
       end 
       else begin
            if (cnt == 5) begin
                cnt <= 0;
            end
            else begin
                cnt <= cnt + 1;
            end
       end
    end

    reg [5:0] tmp;
    always @(posedge clk or negedge rst_n) begin
        if (!rst_n) begin
            tmp <= 0;    
        end
        else begin
            tmp[5-cnt] <= data;
        end
    end

     always @(posedge clk or negedge rst_n) begin
        if (!rst_n) begin
            match <= 0;    
            not_match <= 0;
        end
        else if(tmp == 6'b011100 && cnt == 5) begin
            match <= 1;
            not_match <= 0;
        end
        else if(tmp != 6'b011100 && cnt == 5) begin
            match <= 0;
            not_match <= 1;
        end
        else begin
            match <= 0;    
            not_match <= 0;
        end
    end

endmodule

28题

输入序列不连续的序列检测_牛客题霸_牛客网 (nowcoder.com)

`timescale 1ns/1ns
module sequence_detect(
	input clk,
	input rst_n,
	input data,
	input data_valid,
	output reg match
	);

    reg [3:0] tmp;

  always  @(posedge clk or negedge rst_n)begin
    if(rst_n==1'b0)begin
        tmp <= 0;
    end
    else if(data_valid) begin
        tmp <= {tmp[2:0],data};
    end
  end


  always  @(posedge clk or negedge rst_n)begin
    if(rst_n==1'b0)begin
        match <= 0;
    end
    else if(tmp[2:0] == 3'b011 && data_valid && data == 0) begin
        match <= 1;
    end
    else begin
        match <= 0;
    end
        
  end
endmodule