use Tk;
my $mw = MainWindow -> new;
$mw -> title("Test Code With Serial Port and GUI");

my $btn_01=$mw->Button(-text =>"Done",
                       -command=>sub{exit})
              ->pack;

my $btn_02=$mw->Button(-text=>"Serial Port",
                       -command=>sub{$thr=threads->new(\&serial_port)})
              ->pack;

MainLoop;