`timescale 1ns/1ns module sequence_detect( input clk, input rst_n, input a, output reg match ); reg [7:0] data; reg [2:0] bit_cnt; reg flag; always@(posedge clk or negedge rst_n) if(!rst_n) bit_cnt <= 3'd0; else bit_cnt <= bit_cnt + 1'b1; always@(posedge clk or negedge rst_n) if(!rst_n) flag <= 1'b0; else if(bit_cnt == 3'd7) flag <= 1'b1; else flag <= 1'b0; always@(posedge clk or negedge rst_n) if(!rst_n) data <= 8'd0; else data[7-bit_cnt] <= a; always@(posedge clk or negedge rst_n) if(!rst_n) match <= 1'b0; else if(flag && data==8'b0111_0001) match <= 1'b1; else match <= 1'b0; endmodule