ncount.txt

全数字锁相环（adpll)的部分源程序代码

Library IEEE; 
Use IEEE.std_logic_1164.all; 
Use ieee.std_logic_unsigned.all;
Use IEEE.std_logic_arith.all; 
Entity ncount is 
    Port( FIN: in std_logic; 
 VOUT: out std_logic); 
end ncount; 
architecture arch of ncount is 
    signal count : integer range 0 to 63; 
begin 
process (FIN) 
begin 
  if rising_edge(FIN) then 
     count<=count+1; 
         if count>=32  then VOUT<='1'; 
                    else VOUT<='0';  
     end if; 
  end if; 
end process; 
end arch;