Php 财政打印机的自定义CRC解码算法

我遇到了麻烦，需要你的帮助。我有一个财政打印机（Datecs DP-50）集成在一个chrome扩展应用程序上，可以进行销售。问题是我们无法使用驱动程序，因为应用程序将在远程服务器上运行，而不是在运营商设备上运行，并且我们必须原始发送数据。 该应用程序使用PHP编写，使用Laravel5.1作为额外信息

所以我有一个CRC基数16和一个自定义的多项式x^15+1，但它比这个稍多一些，我无法计算出来。我将把手册中的文档粘贴到下面

   The two CRC bytes are calculated according to the formula x^15 + 1. In the 
    calculation are included all data bytes plus the byte for block end. Every byte passes 
    through the calculation register from teh MSB to LSB.
    Three working bytes are used - S1, S0 and TR
    S1 - Most significant byte from the CRC ( it is transmitted immediatelly after END)
    S0 - Least significant byte from the CRC ( It is transmitted after S1)
    TR - the current transmitted byte in the block.

    The CRC is calculated as follows:
    1. S1 and S0 are zeroed
    2. TR is loaded with the current transmitted byte. The byte is transmitted.
    3. Points 3.1 and 3.2 are executed 8 times:
    3.1. S1, S0 and TR are shifted one bit to the left.
    3.2. If the carry bit from S1 is 1, the MSB of S1 and LSB of S0 are inverted.
    Points 2 and 3 are executed for all bytes, included in the calculation of the CRC - from 
    the first byte after BEG up to and including byte END.
    4. TR is loaded with 0 and point 3 is executed
    5. TR is loaded with 0 and point 3 is executed
    6. Byte S1 is transmitted
    7. Byte S0 is transmitted

例如，“A”字符串的CRC（仅S1和S0）为十六进制：fe 09。对于“B”=>fc 09，对于“C”=>7d f6。“A”的完整CRC为0d fe 09。 串行COM监视器的TR似乎是一个常数，始终表示为0d十六进制

任何帮助解码这是感激的。

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提前谢谢

除了拼写错误之外，该描述还有缺陷，因为它遗漏了关键细节，即S1、S0、TR寄存器按顺序在向左移位时将被视为单个24位寄存器。如果你这样做，那么你就会得到你引用的结果。您需要在计算中包含

0x0d

（“结束”字节）

函数crc16（$crc，$byte）{
$crc=（$crc很抱歉，我对低级编程的知识非常有限，英语不是我的母语。是的，我在计算中遗漏了结束字节，所以我的结果是错误的。我在这里也找到了算法的js实现：。检查js代码的元素。谢谢标记！
function crc16($crc, $byte) {
    $crc = ($crc << 8) + $byte;
    for ($k = 0; $k < 8; $k++)
        $crc = ($crc & 0x800000) == 0 ? $crc << 1 : ($crc << 1) ^ 0x800100;
    $crc = ($crc >> 8) & 0xffff;
    return $crc;
}

$crc = 0;
$crc = crc16($crc, ord("A"));
$crc = crc16($crc, 13);
$crc = crc16($crc, 0);
$crc = crc16($crc, 0);
echo dechex($crc);