**这是本文档旧的修订版!**

Blink程序

// --------------------------------------------------------------------
// >>>>>>>>>>>>>>>>>>>>>>>>> COPYRIGHT NOTICE <<<<<<<<<<<<<<<<<<<<<<<<<
// --------------------------------------------------------------------
// Module: Blink
// 
// Author: Step
// 
// Description: Display with Nixie tube
// 
// Web: www.ecbcamp.com
// 
// --------------------------------------------------------------------
// Code Revision History :
// --------------------------------------------------------------------
// Version: |Mod. Date:   |Changes Made:
// V1.0     |2015/11/11   |Initial ver
// --------------------------------------------------------------------
module Blink #
(
parameter CNT_NUM = 12500000
)
(
input clk_in,
input rst_n_in,
output led_out
);
 
reg [23:0] cnt = 24'd0;
reg clk_div = 1;
always@(posedge clk_in or negedge rst_n_in) begin
	if(!rst_n_in) begin
		cnt <= 24'd0;
		clk_div <= 1;
	end else begin
		if(cnt>=CNT_NUM-1) begin
			cnt <= 24'd0;
			clk_div <= ~clk_div;
		end else cnt <= cnt + 1;
	end
end
 
assign led_out = clk_div;
 
endmodule