frequence1khz.vhd

来自「fpga交通控制灯」· VHDL 代码 · 共 34 行

library ieee;
use ieee.std_logic_1164.all;
use ieee.std_logic_unsigned.all;

entity frequence1khz is
port(clk :in std_logic;
	 clk1khz : out std_logic);
end entity;

architecture beha of frequence1khz is 
signal count : integer range 0 to 499;
signal z : std_logic:='0';
begin 
	 process(clk)
	 begin
		if(clk'event and clk='1')then
		 	if (count=499) then
				z<= not z;
				count<=0;
			else 
				count<=count+1;
			end if;
		end if;
	end process;
	clk1khz<=z;
end architecture ;