procedure TForm1.Timer1Timer(Sender: TObject);
var
Int10: Integer;
begin
if Odd(GetAsyncKeyState(VK_F10)) then //Hotkey on F10.
  begin
    Inc(Int10);
    Timer2.Interval:=StrToInt(Edit1.Text);
  end;
if odd(Int10) then //If on
  begin
    Timer2.Enabled:=True; //Enables the keypress.
  end
else //If off
  begin
    Timer2.Enabled:=False;//Disables the keypress.
  end;
end;

procedure TForm1.Timer2Timer(Sender: TObject);
var
Window:hwnd;
begin
Window:=FindWindowA('notepad',nil); //Finds notepad.
if Window<>0 then
begin
keybd_event(Ord('B'), 0, 0, 0);
end;
end;

procedure Form1.sendNsecondsWorthOfBtoNotepad( n: integer );
  // Add this procedure to the private, protected, or public part of your form class.
  begin
  timer1.interval := 100;    // one keypress every 1/10th second
  timer1.tag      := n /10;  // number of timeout events to process
  timer1.enabled  := TRUE
  end;
 
procedure Form1.Timer1Timer( sender: tObject );
  // This is the timeout event
  begin
  // Send the keystroke
  keybd_event(Ord('B'), 0, 0, 0);
 
  // One tenth second has passed
  timer1.tag := timer1.tag -100;
 
  // If time is up, stop sending keystrokes
  if timer1.tag = 0 then timer1.enabled := FALSE
  end;
 
procedure Form1.Button1Click( sender: tObject );
  // This procedure starts the process
  var ms: integer;
  begin
  // Convert the user's input if possible. (If not, complain.)
  try ms := strToInt( edit1.text )
  except
    showMessage( 'You must specify the number of milliseconds to send keystrokes' );
    edit1.setFocus;
    exit
    end;
  sendNsecondsWorthOfBtoNotepad( ms )
  end;

type
  TForm1 = class(TForm)
    ...
  public:
    { Public declarations }
    procedure sendNsecondsWorthOfBtoNotepad( n: integer );
  end;
 
...
 
implementation
{$R *.RES}
 
procedure Form1.sendNsecondsWorthOfBtoNotepad( n: integer );
  var ...
  begin
  ...
  end;