top.vhd

基于spartan3火龙刀系列FPGA开发板制作的音乐发生器实验例程

library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
use IEEE.STD_LOGIC_ARITH.ALL;
use IEEE.STD_LOGIC_UNSIGNED.ALL;

entity musicdec is
    Port ( spkout0 : out std_logic;
			  spkout1 : out std_logic;
			  sysclk : in std_logic  );
end musicdec;

architecture Behavioral of musicdec is
signal addr : std_logic_vector ( 23 downto 0);
signal tonestep : std_logic_vector (9 downto 0);
signal tonecode : std_logic_vector (7 downto 0);
signal divcounter : integer range 0 to 999999;
signal f : std_logic;
begin
spkout0<= f;
spkout1<= f;
process (sysclk)
begin
 if sysclk'event and sysclk= '1' then
   if divcounter = 65535 then
   f<= not f;	
	divcounter<=0;
	else 
	  divcounter<=divcounter+1;
	end if;
 end if;
end process;
end Behavioral;


--state_machine: process(musicclk)
--begin
--  if musicclk'event and musicclk='1' then
--  case prestate is
--    when idle=>
--	 		if musickey='0' then 
--				tonecode<=x"00";
--			   prestate<=playmusic;			   
--			 elsif tonekey/="11111"  then
--				tonecode<=x"00";
--            prestate<=playtone;
--			 else
--			   tonecode<=x"00";
--				codeaddr1<=0;
--			   codeaddr2<=0;
--				codeaddr3<=0;
--			   prestate<=idle;
--          end if;
--					 
--    when playtone=>
--	             if tonekey/="11111" then
--					   case tonekey is 
--						  when "11110"=> tonecode<=x"08";
--						  when "11101"=> tonecode<=x"09";
--						  when "11011"=> tonecode<=x"0a";
--						  when "10111"=> tonecode<=x"0b";
--						  when "01111"=> tonecode<=x"0c";
--						  when others=> tonecode<=x"00";
--						end case;
--						prestate<=playtone;
--                else
--					   tonecode<=x"00";
--						prestate<=idle; 
--					 end if;
--    when playmusic=>
--	        if tonekey/="11111" then
--				prestate<=playtone;
--			   else					     
--				case musicno is
--				  when "00" =>	tonecode<=music1(codeaddr1);
--							if codeaddr1=255 then
--						  	  codeaddr1<=0;
--							else
--						  	  codeaddr1<=codeaddr1+1;
--							end if;
--							codeaddr2<=0;
--							codeaddr3<=0;
--				  when "01" => tonecode<=music2(codeaddr2);
--							if codeaddr2=447 then
--						  	  codeaddr2<=0;
--							else
--						  	  codeaddr2<=codeaddr2+1;
--							end if;
--							codeaddr1<=0;
--							codeaddr3<=0;
--						   
--				  when "10" => tonecode<=music3(codeaddr3);
--							if codeaddr3=495 then
--						  	  codeaddr3<=0;
--							else
--						  	  codeaddr3<=codeaddr3+1;
--							end if;
--							codeaddr2<=0;
--							codeaddr1<=0;
--              when "11"=> prestate<=idle;
--				         tonecode<=x"00";
--				         codeaddr1<=0;
--							codeaddr2<=0;
--							codeaddr3<=0;
--				  when others=>null;
--				end case;
--
--    		      if tonecode/=x"ff" then  
--				    prestate<=playmusic;
--				  else
--				    prestate<=idle;
--				  end if;
--			   end if;
--	when others=> null;
--   end case;
--  end if;                  
--end process;;
--
--
--