count1.vhd

采用VHDL语言写了一个函数发生器的程序。内含有各个模块

library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
use IEEE.STD_LOGIC_ARITH.ALL;
use IEEE.STD_LOGIC_UNSIGNED.ALL;

entity count1 is
    Port (sysclk,clk,reset :in std_logic;
         
      led_th,led_hu,led_ten,led_one :out std_logic;
		showone,showten,showhu,showth :out std_logic_vector(3 downto 0)

      );
end count1;

architecture Behavioral of count1 is
signal clkk :std_logic;
signal million,hu_th1,ten_th1,th1,hu1,ten1,one1 : std_logic_vector(3 downto 0);


begin

process(sysclk,reset)
 variable count2: integer;
		variable clk0: std_logic;
		begin
		   if  reset='0' then
			 count2:=0;
			 clk0:='0';
			 elsif sysclk'event and sysclk='1' then
			  count2:=count2+1;
			  if count2=32000000 then
			  clk0:='1';
			  elsif count2=64000000 then
			    count2:=0;
				 clk0:='0';
		     --end if;
			 end if;
			end if;
		clkk<=clk0;

	   end process ;





  




counter9999:process(clk,clkk)
begin


if(  clkk='0') then
   million<="0000";
   hu_th1<="0000";
	ten_th1<="0000";
   th1<="0000";
   hu1<="0000";
   ten1<="0000";
   one1<="0000";
   
elsif(clk'event and clk='1') then
  if clkk='1' then
  if(one1=9) then
     one1<="0000";
        if (ten1=9) then
           ten1<="0000";
              if (hu1=9) then
                hu1<="0000";
                 if (th1=9) then
                   th1<="0000";
						 if ten_th1=9 then
						    ten_th1<="0000";
							 if hu_th1=9 then
							  hu_th1<="0000";
							  if million=9 then
							     million<="0000";
								  else
								  million<=million+1;
								  end if;
							  else
							   hu_th1<=hu_th1+1;
								end if;
						   else
							 ten_th1<=ten_th1+1;
					      end if;
                 else
                   th1<=th1+1;
                 end if;
              else
                hu1<=hu1+1;
              end if;
         else
           ten1<=ten1+1;
         end if;
else
  one1<=one1+1;
end if;
end if;
end if;

end process;


save:process(clkk)
  begin
    
    if(clkk'event and clkk ='0') then
    if million>0 then
	  
     led_th<='0';
     led_hu<='1';
	   led_ten<='1';
		 led_one<='1';
     showth<=million;
     showhu<=hu_th1;
     showten<=ten_th1;
     showone<=th1;
      
    
     
	 elsif hu_th1>0 then
     showth<=hu_th1;
     showhu<=ten_th1;
     showten<=th1;
     showone<=hu1;
	  led_th<='1';
     led_hu<='0';
	   led_ten<='1';
		 led_one<='1';
    elsif  ten_th1>0 then
	 
     showth<=ten_th1;
     showhu<=th1;
     showten<=hu1;
     showone<=ten1;
	  led_th<='1';
     led_hu<='1';
	   led_ten<='0';
		 led_one<='1';

    else
     showth<=th1;
     showhu<=hu1;
     showten<=ten1;
     showone<=one1;
     led_th<='1';
     led_hu<='1';
	   led_ten<='1';
		 led_one<='0';
     end if;
	  end if;
end process;




  

end Behavioral;