fpga-midi-synth

library ieee; 
use ieee.std_logic_1164.all; 
use ieee.numeric_std.all; 
use ieee.numeric_bit.all; 

library work;
use work.all;

entity PlayNote is 
port (
   clk   : in  std_logic;
   note  : in  integer;
   audio : out std_logic
); 
end playnote; 
 
architecture Behavioral of PlayNote is 

signal c : integer range 0 to 24999999 := 0;
signal x : std_logic:= '0';

type note_type is array(0 to 127)of integer;
signal notes: note_type;

begin

--teiler fuer die 127 midi noten, generiert mit dem note.rb script
notes <= (
6115610,5772367,5448389,5142594,4853963,4581531,4324389,4081680,3852593,3636363,3432270,3239631,
3057805,2886183,2724194,2571297,2426981,2290765,2162194,2040840,1926296,1818181,1716135,1619815,
1528902,1443091,1362097,1285648,1213490,1145382,1081097,1020420,963148 ,909090 ,858067 ,809907,
 764451, 721545, 681048, 642824, 606745, 572691, 540548, 510210,481574 ,454545 ,429033 ,404953,
 382225, 360772, 340524, 321412, 303372, 286345, 270274, 255105,240787 ,227272 ,214516 ,202476,
 191112, 180386, 170262, 160706, 151686, 143172, 135137, 127552,120393 ,113636 ,107258 ,101238,
  95556,  90193,  85131,  80353,  75843,  71586,  67568,  63776,60196  ,56818  ,53629  ,50619,
  47778,  45096,  42565,  40176,  37921,  35793,  33784,  31888,30098  ,28409  ,26814  ,25309,
  23889,  22548,  21282,  20088,  18960,  17896,  16892,  15944,15049  ,14204  ,13407  ,12654,
  11944,  11274,  10641,  10044,   9480,   8948,   8446,   7972,7524   ,7102   ,6703   ,6327,
   5972,   5637,   5320,   5022,   4740,   4474,   4223,   3986
);

process(clk) begin  
   if(rising_edge(clk)) then -- warten bis zum naechsten Takt 
      if (note < 128) then
         if (c<notes(note)) then
            c <= c+1;               -- wenn kleiner: weiterzaehlen 
         else                       -- wenn Zaehlerende erreicht: 
            c <= 0;                 -- Zaehler zurcksetzen 
            x <= not x;             -- und Signal x togglen 
         end if;
      end if;
   end if;
end process;
audio <= x;

end Behavioral;