www.pudn.com > cpld_laser.rar > sine_32.vhd

library ieee; 
use ieee.std_logic_1164.all; 
use ieee.std_logic_arith.all; 
use ieee.std_logic_unsigned.all; 
 
entity sine_32 is 
                 port(clk,rst: in std_logic; 
                      q_3: out std_logic; 
                      sel:in std_logic; 
                      data_out: out std_logic_vector(7 downto 0)); 
end sine_32; 
 
architecture behav of sine_32  is 
signal cnt: integer range 0 to 31; 
signal cnt_temp: std_logic_vector(4 downto 0); 
signal temp_dataout: integer range 0 to 255; 
begin 
 
   process(clk,rst)  
     begin 
        if rst='1' then cnt<= 0; 
        elsif clk'event and clk='1' then 
            if cnt=31 then cnt<=0; 
            else cnt <= cnt+1; 
            end if; 
        end if; 
   end process; 
 
 
   process(cnt) is 
     begin 
       if sel='0' then 
                 case cnt is 
                     when 0 => temp_dataout<=127; 
                     when 1 => temp_dataout<=152; 
                     when 2 => temp_dataout<=176; 
                     when 3 => temp_dataout<=197; 
                     when 4 => temp_dataout<=217; 
                     when 5 => temp_dataout<=233; 
                     when 6 => temp_dataout<=244; 
                     when 7 => temp_dataout<=252; 
                     when 8 => temp_dataout<=254; 
                     when 9 => temp_dataout<=252; 
                     when 10 => temp_dataout<=244; 
                     when 11 => temp_dataout<=233; 
                     when 12 => temp_dataout<=217; 
                     when 13 => temp_dataout<=197; 
                     when 14 => temp_dataout<=176; 
                     when 15 => temp_dataout<=152; 
                     when 16 => temp_dataout<=127; 
                     when 17 => temp_dataout<=102; 
                     when 18 => temp_dataout<=78; 
                     when 19 => temp_dataout<=57; 
                     when 20 => temp_dataout<=37; 
                     when 21 => temp_dataout<=21; 
                     when 22 => temp_dataout<=10; 
                     when 23 => temp_dataout<=02; 
                     when 24 => temp_dataout<=0; 
                     when 25 => temp_dataout<=02; 
                     when 26 => temp_dataout<=10; 
                     when 27 => temp_dataout<=21; 
                     when 28 => temp_dataout<=37; 
                     when 29 => temp_dataout<=57; 
                     when 30 => temp_dataout<=78; 
                     when 31 => temp_dataout<=102; 
                     when others=>temp_dataout<=0; 
                  end case; 
        else 
                  case cnt is 
                     when 0 => temp_dataout<=127; 
                     when 1 => temp_dataout<=102; 
                     when 2 => temp_dataout<=78; 
                     when 3 => temp_dataout<=57; 
                     when 4 => temp_dataout<=37; 
                     when 5 => temp_dataout<=21; 
                     when 6 => temp_dataout<=10; 
                     when 7 => temp_dataout<=02; 
                     when 8 => temp_dataout<=0; 
                     when 9 => temp_dataout<=02; 
                     when 10 => temp_dataout<=10; 
                     when 11 => temp_dataout<=21; 
                     when 12 => temp_dataout<=37; 
                     when 13 => temp_dataout<=57; 
                     when 14 => temp_dataout<=78; 
                     when 15 => temp_dataout<=102; 
                     when 16 => temp_dataout<=127; 
                     when 17 => temp_dataout<=152; 
                     when 18 => temp_dataout<=176; 
                     when 19 => temp_dataout<=197; 
                     when 20 => temp_dataout<=217; 
                     when 21 => temp_dataout<=233; 
                     when 22 => temp_dataout<=244; 
                     when 23 => temp_dataout<=252; 
                     when 24 => temp_dataout<=254; 
                     when 25 => temp_dataout<=252; 
                     when 26 => temp_dataout<=244; 
                     when 27 => temp_dataout<=233; 
                     when 28 => temp_dataout<=217; 
                     when 29 => temp_dataout<=197; 
                     when 30 => temp_dataout<=176; 
                     when 31 => temp_dataout<=152; 
                     when others=>temp_dataout<=0; 
                  end case; 
     end if; 
end process; 
 
      cnt_temp <= conv_std_logic_vector(cnt,5); 
 
      q_3 <= cnt_temp(3); 
 
 
     data_out <= conv_std_logic_vector(temp_dataout,8); 
 
end behav;