题解 | #边沿检测#
边沿检测
https://www.nowcoder.com/practice/fed4247d5ef64ac68c20283ebace11f4
`timescale 1ns/1ns module edge_detect( input clk, input rst_n, input a, output reg rise, output reg down ); reg a_tem; always @(posedge clk or negedge rst_n) if (!rst_n) a_tem <= 1'b0; else a_tem <= a; always @(posedge clk or negedge rst_n) if (!rst_n) begin rise <= 1'b0; down <= 1'b0; end else if (!a_tem&&a) begin rise<=1'b1; down<=1'b0; end else if (a_tem&&!a) begin rise<=1'b0; down<=1'b1; end else begin rise<=1'b0; down<=1'b0; end endmodule