code.vhd

自定义编码的红外发射器

library ieee;
use ieee.std_logic_1164.all;
use ieee.std_logic_unsigned.all;
entity code is
   port( reset, clk_send, osc, ready_en: in std_logic;
         key_in: in std_logic_vector(12 downto 1);
         tx: out   std_logic
         );
end code;
architecture send of code is
signal temp : std_logic_vector(35 downto 1);
signal C : std_logic_vector( 5 downto 0);
signal d : std_logic_vector(15 downto 0);
signal y: std_logic;

begin
 tx<=y;
  y <= temp(35) and osc ;
aa: process(d,  ready_en, clk_send,osc,y,c,temp,reset)
   begin
    if reset='1' then
       temp<="00000000000000000000000000000000000";
    else
       if ready_en='1'  then                      --- data input         
       temp(35 downto 24)<="010101110010";  ---fram head input
       temp(23 downto 8)<=d;                ----data input
       temp(7 downto 2)<=c;                 ---hammming code input
       --temp(2 downto 1)<="00";
      else          
          if clk_send'event and clk_send='1' then                     
      tx_loop:  for k in 35 downto 2 loop
                 temp(k)<=temp(k-1);
                 end loop tx_loop;
                 temp(1) <='0';
            end if; 
         end if;  
     end if;
  end process aa;


bb: process(key_in,d,ready_en,clk_send,reset)     --- keyboard code
    begin
     if reset='1' then 
         d<="0000000000000000";
     else
       if ready_en='1' then
          if clk_send'event and clk_send='0'then
            case key_in is
            when "111111111110" => d<="0011110000111100"; -- 1 power on and off
            when "111111111101" => d<="0001110001110001"; -- 2 mute on and off
            when "111111111011" => d<="0000111000011100"; -- 3 standby on and off
            when "111111110111" => d<="0011001100110011"; -- 4 Hi up
            when "111111101111" => d<="1100110011001100"; -- 5 Hi down
            when "111111011111" => d<="1110001110001110"; -- 6 Lo up
            when "111110111111" => d<="1111000111100011"; -- 7 Lo down
            when "111101111111" => d<="1101101101101101"; -- 8 Vol up
            when "111011111111" => d<="0101010101010101"; -- 9 Vol down
            when "110111111111" => d<="1001001001001001"; -- 10 Time display
            when "101111111111" => d<="0111001100111001"; -- 11 Sleep on and off
            when "011111111111" => d<="1010101010101010"; -- 12 resaved
            when others  =>        d<="0000000000000000";
            end case;
       end if;
   end if;
  end if;
   end process bb;

cc: process(d,c,key_in,ready_en,reset,clk_send)  -- hamming code 
    begin
     if reset='1' then
        c<="000000";
     else
       if   ready_en='1'   then  
        if clk_send'event and clk_send='0'then              
         c(5)<=d(8) xor d(9) xor d(10) xor d(11) xor d(12) xor d(13) xor d(14) xor d(15);
         c(4)<=d(3) xor d(4) xor  d(5)  xor d(6)  xor d(7) xor d(13) xor d(14) xor d(15);
         c(3)<=d(0) xor d(1) xor  d(2)  xor d(6)  xor d(7) xor d(10) xor d(11) xor d(12);
         c(2)<=d(1) xor d(2) xor  d(4)  xor d(5)  xor d(7)  xor d(9) xor d(12) xor d(15);
         c(1)<=d(0) xor d(2) xor  d(3)  xor d(5)  xor d(6)  xor d(8) xor d(11) xor d(14); 
         c(0)<=d(0) xor d(1) xor  d(3)  xor d(4)  xor d(8)  xor d(9) xor d(10) xor d(13);       
       end if;  
  end if;
end if;
 end process cc;

end send;