pll1.vhd

该程序实现的功能是数字锁相环的设计。源代码可以直接进行仿真试验◎

library ieee; 

use ieee.std_logic_1164.all; 
Use IEEE.std_logic_arith.all; 
use ieee.std_logic_unsigned.all; 

entity pll1 is 

port ( 

 v1,CP,en,d,c,b,a:in std_logic; 

 vout:out std_logic 

 );

end pll1; 

architecture pll_arch of pll1 is 

signal temp1,temp2: std_logic;--a_bxulie
signal tout1,tout2: std_logic;--a_bxulie
signal v2: std_logic;--v2<=VOUT
signal vd:std_logic;--clk<=CP
signal updn,up,dn:std_logic;--updn<=vd
signal cq,k,m:std_logic_vector(16 downto 0); --开始
signal out1,out2:std_logic; 
signal dir:std_logic_vector(3 downto 0); --以上kcount信号
signal inc,dec:std_logic;
signal count : integer range 0 to 63; --开始
signal fin   : std_logic;
signal addtemp,dectemp: std_logic;--以上ncount信号


begin 

dir<=d&c&b&a; 

with dir select 

m<="0000000000000111"when"0001", 

 "0000000000001111"when"0010", 

 "0000000000011111"when"0011", 

 "0000000000111111"when"0100", 

 "0000000001111111"when"0101", 

 "0000000011111111"when"0110", 

 "0000000111111111"when"0111", 

 "0000001111111111"when"1000", 

 "0000011111111111"when"1001", 

 "0000111111111111"when"1010", 

 "0001111111111111"when"1011", 

 "0011111111111111"when"1100", 

 "0111111111111111"when"1101", 

 "1111111111111111"when"1110", 

 "0000000000000111"when others; 

  
  process(v1,v2)   --EXOR

begin
    
   VD<=V1 xor V2; 

   updn<=VD;    

end process;   
   
  process(CP,en,updn,k,cq) --kcount

begin 

if CP'event and CP='1' then 

    k<=m; 

  if en='1' then 

    if updn='0' then 

      if cq<k then cq<=cq+1; 

         else cq<=(others=>'0'); 

      end if; 
    else 

      if cq>0 then cq<=cq-1; 

         else cq<=k; 

      end if; 

    end if; 

  else cq<=(others=>'0'); 

  end if; 

end if; 

end process; 

process(en,updn,cq,k) 

begin 

  if en='1' then 

      if updn='0' then 

          if cq=k then out1<='1'; 

             else out1<='0'; 

          end if; 

          out2 <='0'; 

      else 

         if cq="00000000000000000"then out2<='1'; 

             else out2<='0'; 

         end if; 

         out1<='0'; 

      end if; 

  else out1<='0';out2<='0'; 

  end if; 

up<=out1;dn<=out2; 

end process; 

process(cp)--2分频
begin
if cp'event and cp='1' then
temp1<=not temp1;
end if;
end process;

process(cp)--2分频
begin
if cp'event and cp='0' then
temp2<=not temp2;
end if;
end process;
tout2<=temp1 and temp2;
tout1<=(not temp1) and (not temp2);
--clkao<=tout1; 
--clkbo<=tout2;

  process (tout1)--脉冲加减控制

begin

addtemp<=up and tout1;

end process;

  process(tout2)

begin

dectemp<=(not dn) and tout2;

end process;

FIN<=addtemp or dectemp;--是ctrl的fout，ncounter的fin

  process (FIN) 

begin 

   if rising_edge(FIN) then 

          count<=count+1; 

     if count>=31 then 
         
              v2<='1'; 

         else v2<='0'; 

     end if; 

   end if; 
 
vout<=v2;

end process; 

end pll_arch;