program Noise (input,output);

uses crt;

type
     notes=set of 'A' .. 'Z';

var
     valnotes:char;

(**************************************************************************)

procedure Play_Tone (var valnotes:char);

     var
          intnote:integer;
          noteset:notes;

     begin  {procedure Play_Tone}
          clrscr;
          writeln ('Enter X to end program!');
          writeln;
          noteset:=['A' .. 'z'];
          repeat
               valnotes:=readkey;
               valnotes:=UpCase (valnotes);
          until (valnotes in noteset);
          intnote:=ord (valnotes)*100-6400;
          writeln (intnote);
          Sound (intnote);
          Delay (500);
          NoSound;
     end;   {procedure Play_Tone}

(**************************************************************************)

begin
     repeat
          Play_Tone (valnotes);
     until (valnotes='X');
     NoSound;
end.