div.vhd

用cpld开发的激光控制器的源码

-- MAX+plus II VHDL Template
-- Clearable loadable enablable counter

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


ENTITY div IS
    port   (clk_input		: in	std_logic;
		    compare		    : out	std_logic	);
	
END div;

ARCHITECTURE a OF  div IS

signal	cnt:  std_logic_vector(3 downto 0);
signal  compare_temp: std_logic;
	
BEGIN

	PROCESS (clk_input) is
	BEGIN
	  if (clk_input'event and clk_input='1')
        then
          if cnt="1111" then cnt<="0000";
          else
             cnt <= cnt+1;
          end if;
      end if; 
    END process;
   
   process (clk_input) is
   begin
     if (clk_input'event and clk_input='1')
       then
         if cnt(2 downto 0)="000" then
            compare_temp <= not compare_temp;
         end if;
     end if;
   end  process;
   compare <= compare_temp;
end a;