www.pudn.com > DDSforsinandcos.rar > cntm10.vhd

library ieee; 
use ieee.std_logic_1164.all; 
use ieee.std_logic_unsigned.all; 
entity cntm10 is 
 port( 
    clear : in std_logic; 
    ci :in std_logic; 
    clk :in std_logic; 
    co :out std_logic; 
    qout : buffer std_logic_vector(3 downto 0) 
); 
end cntm10; 
architecture behave of cntm10 is 
  begin  
    co<='1'when(qout="1001"and ci='1') else '0'; 
   
  process(clk,clear) 
    begin 
      if(clear='1')then 
              qout<="0000"; 
        elsif(clk'event and clk='1')then 
         if(ci='1')then 
            if(qout="1001") then  
                qout<="0000"; 
 
         else qout<=qout+1; 
      end if; 
    end if; 
  end if; 
   end process; 
end behave;