protected static function printHex($value)
    {
        $tabVal = ['0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'];
        $hex = '';
        for ($i = 0; $i < strlen($value); $i++) {
            $lsig = ord(substr($value, $i, 1)) % 16;
            $msig = (ord(substr($value, $i, 1)) - $lsig) / 16;
            $lessSig = $tabVal[$lsig];
            $moreSig = $tabVal[$msig];
            $hex .= $moreSig . $lessSig;
        }

        return $hex;
    }