protected function getControlCharactersEscapingMap()
    {
        $controlCharactersEscapingMap = [];

        // control characters values are from 0 to 1F (hex values) in the ASCII table
        for ($charValue = 0x00; $charValue <= 0x1F; $charValue++) {
            $character = chr($charValue);
            if (preg_match("/{$this->escapableControlCharactersPattern}/", $character)) {
                $charHexValue = dechex($charValue);
                $escapedChar = '_x' . sprintf('%04s' , strtoupper($charHexValue)) . '_';
                $controlCharactersEscapingMap[$escapedChar] = $character;
            }
        }

        return $controlCharactersEscapingMap;
    }