Mike42\Escpos\CodePage::generateEncodingMap PHP Method

    protected static function generateEncodingMap($iconvName)
    {
        // Start with array of blanks (" " indicates unknown character).
        $charMap = array_fill(0, 128, " ");
        // Loop through 128 code points
        for ($char = 128; $char <= 255; $char++) {
            // Try to identify the UTF-8 character that would go here
            $utf8 = @iconv($iconvName, self::INPUT_ENCODING, chr($char));
            if ($utf8 == '') {
                continue;
            }
            if (iconv(self::INPUT_ENCODING, $iconvName, $utf8) != chr($char)) {
                // Avoid non-canonical conversions (no known examples)
                continue;
            }
            // Replace the ' ' with the correct character if we found it
            $charMap[$char - 128] = $utf8;
        }
        // Join into a 128-character string and return.
        $charMapStr = implode("", $charMap);
        assert(mb_strlen($charMapStr, self::INPUT_ENCODING) == 128);
        return $charMapStr;
    }