Convertir Hex en Binario

uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls,
 Forms, Dialogs, StdCtrls, Buttons;
 
type
  TForm1 = class(TForm)
    Edit1: TEdit;
    P07: TStaticText;
    P06: TStaticText;
    P04: TStaticText;
    P03: TStaticText;
    P02: TStaticText;
    P01: TStaticText;
    P00: TStaticText;
    P05: TStaticText;
    BitBtn1: TBitBtn;
    Label1: TLabel;
    Label2: TLabel;
    Label3: TLabel;
    Label4: TLabel;
    Label5: TLabel;
    Label6: TLabel;
    Label7: TLabel;
    Label8: TLabel;
    Label9: TLabel;
    Label10: TLabel;
    Label11: TLabel;
    Label12: TLabel;
    procedure BitBtn1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;
 
var
  Form1: TForm1;
  Binario: string;
 
implementation
 
{$R *.DFM}
 
function FastIntToBin(Num: cardinal; Length: integer): string;
var
  i: cardinal;
begin
  i := 1;
  Result := '';
  while (i <= Num) or (system.Length(Result) < Length) do begin
    if Num and i = i then
      Result := '1' + Result
    else
      Result := '0' + Result;
    i := i * 2;
  end;
end;
 
procedure TForm1.BitBtn1Click(Sender: TObject);
begin
  Binario := FastInttoBin(strtoint('$' + Edit1.text),8);
  P07.Caption := Binario[1];
  P06.Caption := Binario[2];
  P05.Caption := Binario[3];
  P04.Caption := Binario[4];
  P03.Caption := Binario[5];
  P02.Caption := Binario[6];
  P01.Caption := Binario[7];
  P00.Caption := Binario[8];
end;
 
end.