sub tdSensor {
    my( $protocolLen, $modelLen ) = @_;
    $protcolLen ||= 1024;
    $modelLen ||= 1024;
    my $protocol = '\0' x $protcolLen;
    my $model = '\0' x $modelLen;
    my $id = 0;
    my $dataTypes = 0;
    my $ret = _tdSensor(
        $protocol, $protocolLen, $model, $modelLen, $id, $dataTypes );
    s/\0.*//
        for $protocol, $model;
    return( $ret, $protocol, $model, $id, $dataTypes );
}