my @tx_grid_frame;
my @outputEnaLpbkBut;
for (my $i = 0; $i < $self->{NUM_OF_LANE_MAX}; ++$i){
    $tx_grid_frame[$i+1][1] = $quick_tx_right_frm->Frame(-relief=>'groove', -bd=>1)->grid(-row => $i+1, -column => 1, -columnspan => 1,  -rowspan => 1, -sticky => 'nsew');

    #Output enable when loopback
    $outputEnaLpbkBut[$i] =  $self->{W}->Add_Chk($tx_grid_frame[$i+1][1], '', 'top');
    $outputEnaLpbkBut[$i] -> configure(-variable=> \${$self->{OUTPUT_ENA_LPBK}}[$i], -command => sub{
      print "Test $i \n";
    });
  }