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
