eval "use Device::SerialPort; 1" or die $@;
   my $directory = '/dev';
   opendir (DIR, $directory) or die $!;
   while (my $file = readdir(DIR)) {
        #print "$file\n";
        push (@ports, "$directory/$file") if ($file =~ /ttyS/g);
        push (@ports, "$directory/$file") if ($file =~ /ttyUSB/g);
   }
       closedir(DIR);
       foreach my $port (@ports){
          no warnings 'redefine';
          local *Device::SerialPort::carp = sub {};
          $PortObj = new Device::SerialPort($port, 1) or next;
          $PortObj->close;
          push(@ok_ports, $port);
          sleep (1);
    };