tonetaba.vhd

一个使用VHDL编写的音乐芯片的程序有很好的使用价值

library ieee;
use ieee.std_logic_1164.all;
entity tonetaba is
  port(tonecodein:  in integer range 0 to 21;
       musicfreqout:out integer range 0 to 2047);
end;

architecture behav of tonetaba is
begin
  search:process(tonecodein)
  begin
     case tonecodein is
            when 0=>musicfreqout<=2047;
            when 1=>musicfreqout<=1091; 
            when 2=>musicfreqout<=1196; 
            when 3=>musicfreqout<=1289; 
            when 4=>musicfreqout<=1331; 
            when 5=>musicfreqout<=1409;
            when 6=>musicfreqout<=1479; 
            when 7=>musicfreqout<=1541; 
            
            when 8=>musicfreqout<=136; 
            when 9=>musicfreqout<=344; 
            when 10=>musicfreqout<=530; 
            when 11=>musicfreqout<=616; 
            when 12=>musicfreqout<=771;
            when 13=>musicfreqout<=911; 
            when 14=>musicfreqout<=1035;  
            
            when 15=>musicfreqout<=1569; 
            when 16=>musicfreqout<=1621; 
            when 17=>musicfreqout<=1668; 
            when 18=>musicfreqout<=1689; 
            when 19=>musicfreqout<=1728;
            when 20=>musicfreqout<=1763; 
            when 21=>musicfreqout<=1794; 


  
            when others=>null;
     end case;
  end process;
end;