Question

我需要帮助计算CRC X25变体，我有一个Java工具，也有一个可以正确转换的在线工具，但我自己也无法重现它。

字符串：40402900033231334C323031373030313839360000000000009001FFFFFFFF0000D656B759 输入类型：十六进制 - ＆gt; Calc CRC16

Result: CRC-16/X-25 
0x6C49 <-- this is the value im trying to get in php from that string above.

到目前为止，我的Php代码

private static $CRC16_Table = array
    (0x0000, 0x1189, 0x2312, 0x329B, 0x4624, 0x57AD,
    0x6536, 0x74BF, 0x8C48, 0x9DC1, 0xAF5A, 0xBED3,
    0xCA6C, 0xDBE5, 0xE97E, 0xF8F7, 0x1081, 0x0108,
    0x3393, 0x221A, 0x56A5, 0x472C, 0x75B7, 0x643E,
    0x9CC9, 0x8D40, 0xBFDB, 0xAE52, 0xDAED, 0xCB64,
    0xF9FF, 0xE876, 0x2102, 0x308B, 0x0210, 0x1399,
    0x6726, 0x76AF, 0x4434, 0x55BD, 0xAD4A, 0xBCC3,
    0x8E58, 0x9FD1, 0xEB6E, 0xFAE7, 0xC87C, 0xD9F5,
    0x3183, 0x200A, 0x1291, 0x0318, 0x77A7, 0x662E,
    0x54B5, 0x453C, 0xBDCB, 0xAC42, 0x9ED9, 0x8F50,
    0xFBEF, 0xEA66, 0xD8FD, 0xC974, 0x4204, 0x538D,
    0x6116, 0x709F, 0x0420, 0x15A9, 0x2732, 0x36BB,
    0xCE4C, 0xDFC5, 0xED5E, 0xFCD7, 0x8868, 0x99E1,
    0xAB7A, 0xBAF3, 0x5285, 0x430C, 0x7197, 0x601E,
    0x14A1, 0x0528, 0x37B3, 0x263A, 0xDECD, 0xCF44,
    0xFDDF, 0xEC56, 0x98E9, 0x8960, 0xBBFB, 0xAA72,
    0x6306, 0x728F, 0x4014, 0x519D, 0x2522, 0x34AB,
    0x0630, 0x17B9, 0xEF4E, 0xFEC7, 0xCC5C, 0xDDD5,
    0xA96A, 0xB8E3, 0x8A78, 0x9BF1, 0x7387, 0x620E,
    0x5095, 0x411C, 0x35A3, 0x242A, 0x16B1, 0x0738,
    0xFFCF, 0xEE46, 0xDCDD, 0xCD54, 0xB9EB, 0xA862,
    0x9AF9, 0x8B70, 0x8408, 0x9581, 0xA71A, 0xB693,
    0xC22C, 0xD3A5, 0xE13E, 0xF0B7, 0x0840, 0x19C9,
    0x2B52, 0x3ADB, 0x4E64, 0x5FED, 0x6D76, 0x7CFF,
    0x9489, 0x8500, 0xB79B, 0xA612, 0xD2AD, 0xC324,
    0xF1BF, 0xE036, 0x18C1, 0x0948, 0x3BD3, 0x2A5A,
    0x5EE5, 0x4F6C, 0x7DF7, 0x6C7E, 0xA50A, 0xB483,
    0x8618, 0x9791, 0xE32E, 0xF2A7, 0xC03C, 0xD1B5,
    0x2942, 0x38CB, 0x0A50, 0x1BD9, 0x6F66, 0x7EEF,
    0x4C74, 0x5DFD, 0xB58B, 0xA402, 0x9699, 0x8710,
    0xF3AF, 0xE226, 0xD0BD, 0xC134, 0x39C3, 0x284A,
    0x1AD1, 0x0B58, 0x7FE7, 0x6E6E, 0x5CF5, 0x4D7C,
    0xC60C, 0xD785, 0xE51E, 0xF497, 0x8028, 0x91A1,
    0xA33A, 0xB2B3, 0x4A44, 0x5BCD, 0x6956, 0x78DF,
    0x0C60, 0x1DE9, 0x2F72, 0x3EFB, 0xD68D, 0xC704,
    0xF59F, 0xE416, 0x90A9, 0x8120, 0xB3BB, 0xA232,
    0x5AC5, 0x4B4C, 0x79D7, 0x685E, 0x1CE1, 0x0D68,
    0x3FF3, 0x2E7A, 0xE70E, 0xF687, 0xC41C, 0xD595,
    0xA12A, 0xB0A3, 0x8238, 0x93B1, 0x6B46, 0x7ACF,
    0x4854, 0x59DD, 0x2D62, 0x3CEB, 0x0E70, 0x1FF9,
    0xF78F, 0xE606, 0xD49D, 0xC514, 0xB1AB, 0xA022,
    0x92B9, 0x8330, 0x7BC7, 0x6A4E, 0x58D5, 0x495C,
    0x3DE3, 0x2C6A, 0x1EF1, 0x0F78,
);

public static function calculate($buffer) {
    $length = strlen($buffer);

    $crc = 0;
    $i = 0;
    while ($length--) {
        $crc = (( $crc >> 8) & 0xff) ^ (self::$CRC16_Table[(ord($buffer[$i++]) ^ $crc) & 0xFF]);
    }

    return (($crc & 0xFFFF) ^ 0x8000) - 0x8000;
}

public static function ComputeCrc($data) {
    $crc = 0xFFFF;

    foreach ($data as $d) {
        $crc = self::$CRC16_Table[($d ^ $crc) & 0xFF] ^ ($crc >> 8 & 0xFF);
    }

    $crc = $crc ^ 0xFFFF;
    $crc = $crc & 0xFFFF;

    return $crc;
}

这给我的结果如下

ComputeCrc(str_split("40402900033231334C323031373030313839360000000000009001FFFFFFFF0000D656B759", 2));
Result = ec71 <-- decHex result

calculate("40402900033231334C323031373030313839360000000000009001FFFFFFFF0000D656B759");
Result = 48d7; <-- decHex result

非常感谢任何帮助

Answer 1

解决了它在计算之前应用hexdec，将来可能会有用。

public static function ComputeCrc($data) {
    $crc = 0xFFFF;

    foreach ($data as $d) {
        $d = hexdec($d); <-- This did the trick
        $crc = self::$CRC16_Table[($d ^ $crc) & 0xFF] ^ ($crc >> 8 & 0xFF);
    }

    $crc = $crc ^ 0xFFFF;
    $crc = $crc & 0xFFFF;

    return $crc;
}

在php中计算CRC16 X25

1 个答案: