keyin.vhd

此为用VHDL编写的可实现动感图像的点阵

library ieee;
USE IEEE.STD_LOGIC_1164.ALL;
ENTITY keyin IS
	PORT(	clk	: IN	STD_LOGIC;
		reset	: IN	STD_LOGIC;
		resetn 	: OUT  	STD_LOGIC);
END keyin;
ARCHITECTURE a OF keyin IS
	SIGNAL resetmp1,resetmp2 : STD_LOGIC;
BEGIN
PROCESS(clk)
BEGIN
IF (clk'EVENT AND clk='0') THEN
	resetmp2<= resetmp1;
	resetmp1<= reset;
END IF;
END PROCESS;
	resetn<=clk AND resetmp1 AND (NOT resetmp2);
END a;