c_fenpin2.vhd

cpld数据采集测频

--本程序时钟采用
--40MHz的CLK
--得到一系列
--固定频率的时钟
library ieee;
use ieee.std_logic_1164.all;
use ieee.std_logic_unsigned.all;

entity c_fenpin2 is
    port(clk,trigger,m_signal:in std_logic; --trigger触发信号，m_signal测量信号
             fad,fda:out std_logic);   --fad采样频率，fda显示频率
          
end;

architecture behav of c_fenpin2 is
   signal c1,f1,f2,f3,f4,f5,f6,f7,f8,f9,f10,f11,f12,f13,f14:integer;
   signal count,timer:integer;         --count计数变量，timer定时变量
   signal clk1,clk2,y1,y2,y3,y4,y5,y6,y7,y8,y9,y10,y11,y12,y13,y14:std_logic;
   signal trig,flag1:std_logic:='0';   --flag1是否测频标志，1不测
                                       --trig触发信号，1触发
begin

--下面两个进程用于测频
--用于定时1S
--clk1为1kHz
process(clk1,trig,flag1)
    begin
        if trig='0' then
            timer<=0;
        elsif clk1'event and clk1='1' then
            if timer=999 then
                flag1<='1';
            else
                timer<=timer+1;
            end if;
        end if;
    end process;
--用于脉冲计数
process(m_signal,trig,flag1)
    begin
        if trig='0' then
            count<=0;
        elsif flag1='1' then
            count<=count;
        elsif m_signal'event and m_signal='1' then
            count<=count+1;
        end if;
end process;


--采样频率选择器
process(count)
    begin 
        if flag1='1' then
            if count<=2 then
                clk2<=y1;
            elsif  count<=4 then
                clk2<=y2;
            elsif  count<=8 then
                clk2<=y3;
            elsif  count<=16 then
                clk2<=y4;
            elsif  count<=32 then
                clk2<=y5;
            elsif  count<=64 then
                clk2<=y6;
            elsif  count<=128 then
                clk2<=y7;
            elsif  count<=256 then
                clk2<=y8;
            elsif  count<=512 then
                clk2<=y9;
            elsif  count<=1024 then
                clk2<=y10;
            elsif  count<=2048 then
                clk2<=y11;
            elsif  count<=4096 then
                clk2<=y12;
            elsif  count<=8192 then
                clk2<=y13;
            else 
                clk2<=y14;
            end if;
       end if;
end process;
fad<=clk2;
fda<=clk1;
            
            
process(trigger)
    begin
        if trigger'event and trigger='1'  then
            trig<='1';
        end if;
end process;
           

process(clk,trig)
begin
  if trig='0' then
     c1<=0;
     f1<=0;
     f2<=0;
     f3<=0;
     f4<=0;
     f5<=0;
     f6<=0;
     f7<=0;
     f8<=0;
     f9<=0;
     f10<=0;
     f11<=0;
     f12<=0;
     f13<=0;
     f14<=0;     
  else if clk'event and clk='1'  then
     if c1=39999 then
         c1<=0;
     else 
         c1<=c1+1;
     end if;

     if f1=999999 then
        f1<=0;
     else 
        f1<=f1+1;
     end if;

    if f2=499999 then
        f2<=0;
     else 
        f2<=f2+1;
     end if;

    if f3=249999 then
        f3<=0;
     else 
        f3<=f3+1;
     end if; 

    if f4=124999 then
        f4<=0;
     else 
        f4<=f4+1;
     end if;
     
    if f5=62499 then
        f5<=0;
     else 
        f5<=f5+1;
     end if;

    if f6=31249 then
        f6<=0;
     else 
        f6<=f6+1;
     end if;

    if f7=15624 then
        f7<=0;
     else 
        f7<=f7+1;
     end if; 

    if f8=7811 then
        f8<=0;
     else 
        f8<=f8+1;
     end if;

    if f9=3905 then
        f9<=0;
     else 
        f9<=f9+1;
     end if;

    if f10=1952 then
        f10<=0;
     else 
        f10<=f10+1;
     end if;

    if f11=976 then
        f11<=0;
     else 
        f11<=f11+1;
     end if; 

    if f12=487 then
        f12<=0;
     else 
        f12<=f12+1;
     end if;

    if f13=243 then
        f13<=0;
     else 
        f13<=f13+1;
     end if;

    if f14=121 then
        f14<=0;
     else 
        f14<=f14+1;
     end if;
  
   end if;
end if;
end process;
  


process(clk)
  begin
      if trig='1' then
         if c1<20000 then
            clk1<='0';
         else
            clk1<='1';
         end if;

         if f1<500000 then
             y1<='0';
         else
             y1<='1';
         end if;

        if f2<250000 then
             y2<='0';
         else
             y2<='1';
         end if;

         if f3<125000 then
             y3<='0';
         else
             y3<='1';
         end if;

         if f4<62500 then
             y4<='0';
         else
             y4<='1';
         end if;

         if f5<31250 then
             y5<='0';
         else
             y5<='1';
         end if;

        if f6<15625 then
             y6<='0';
         else
             y6<='1';
         end if;

         if f7<7812 then
             y7<='0';
         else
             y7<='1';
         end if;

         if f8<3906 then
             y8<='0';
         else
             y8<='1';
         end if;

         if f9<1953 then
             y9<='0';
         else
             y9<='1';
         end if;

        if f10<976 then
             y10<='0';
         else
             y10<='1';
         end if;

         if f11<488 then
             y11<='0';
         else
             y11<='1';
         end if;

         if f12<244 then
             y12<='0';
         else
             y12<='1';
         end if;

        if f13<122 then
             y13<='0';
         else
             y13<='1';
         end if;

         if f14<61 then
             y14<='0';
         else
             y14<='1';
         end if;
     
     end if;
 end process;   


end;