segue o codigo unit Unit1; interface uses Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs, StdCtrls; type TForm1 = class(TForm) Button1: TButton; Edit1: TEdit; procedure Button1Click(Sender: TObject); private { Private declarations } public { Public declarations } end; var Form1: TForm1; function encode(key, v_s :variant): variant; stdcall; external 'cast.dll' name 'encode'; implementation {$R *.DFM} procedure TForm1.Button1Click(Sender: TObject); begin edit1.Text := encode('ice', '123'); end; end. a documentação da dll esta no link abaixo http://download.paipai.net/texts/asp-cast128-1.1.htm obrigado !!!!!!!!!