flash_led.v

来自「EPM1270下的 LED闪烁程序」· Verilog 代码 · 共 43 行

/************************************************************
*		FILE NAME:		FLASH_LED.V
*		FUNCTION:		1.
*						2. 
*						3.
*						4.
*		CREATED BY:		Wenzhuan Wang
*						hi.baidu.com/nailson
*		CREATED DATA:	2009-01-15
*------------------------------------------------------------
*		HISTORY:
*------------------------------------------------------------			
*		MODIFIED DATA	2009-01-15
*		DESCRIPTIONS:	create this file
*************************************************************/
module FLASH_LED(ctrl_out,clk,rst);

	output ctrl_out;
	input clk;
	input rst;
	
	//reg[25:0] cntr;
	integer cntr;
	reg ctrl_out;
always@(posedge clk or negedge rst)
	if(!rst)begin
	cntr<=0;
	ctrl_out=0;
	end
	
	else begin
		if(cntr==5000000)begin//25MHz  1s
		cntr<=0;
		ctrl_out<=~ctrl_out;
		end
		else begin
		cntr<=cntr+1;
		end
	end

endmodule