标题中提到的指南（从）完全帮助我掌握了CRC算法的原理和手动实现。在第9和第10节中，我击中了可能是小障碍的东西。
我在 9节中不了解的细节。在此部分中，桌子驱动的实现，其中消息字节被转移到右侧的登记册中（强调报价是我的）：
•寄存器的顶部字节现在无关紧要。无论在接下来的8次迭代中，多次多次和以什么偏移构成了poly被固定到前8位。
•剩下的位将移动左一个位置，并且寄存器的大多数字节将在下一个字节中移动
我认为我认为“右侧”应该在第一个子弹中“左侧”观点？
在 10节中。一个略微处理的桌子驱动实现，
关于处理要检查的消息末尾的零字节问题的问题，我对以下内容感到困惑：
您知道的问题是，此循环在增强消息上运行，为了使用此代码，您必须将 w/8 零字节附加到消息的末尾，然后p at。
这很明确（多项式具有宽度32），但是在随后的代码中，在本节中，作者使用w/4：
（i = 0; i＆lt; i＆lt; w/4; i ++） r =（r＆lt;＆lt; 8） ^ t [（r＆gt;＆gt; 24）＆amp; 0xff];
我认为这也应该有w/8？
The guide mentioned in the title (downloaded from http://ross.net/crc/download/crc_v3.txt) has perfectly helped me grasp the principle, and the manual implementation, of a CRC algorithm. In sections 9 and 10 I hit what probably are minor snags.
The detail I do not understand in section 9. A Table-Driven Implementation, where message bytes are shifted into a register from the right, is in this part (emphasis in quotations is mine):
• The top byte of the register now doesn't matter. No matter how many times and at what offset the poly is XORed to the top 8 bits, they will all be shifted out the right hand side during the next 8 iterations anyway.
• The remaining bits will be shifted left one position and the rightmost byte of the register will be shifted in the next byte
I would think "right hand side" should be "left hand side" in the first bullet point?
In section 10. A Slightly Mangled Table-Driven Implementation,
about dealing with the issue of appending zero bytes to the end of the message to be checked, I am confused by the following:
The trouble, you see, is that this loop operates upon the AUGMENTED message and in order to use this code, you have to append W/8 zero bytes to the end of the message before pointing p at it.
That is perfectly clear (the polynomial has width 32), but in the code that follows, and further down in the section, the author uses W/4:
for (i=0; i<W/4; i++) r = (r << 8) ^ t[(r >> 24) & 0xFF];
I would think that this should also have W/8?
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该文本文件中有错别字。顶部字节很重要，因为每个非零位导致多项式被XOR XOR到寄存器，并且该点的位正在向左移动。 w/4应该是w/8，但在以后的示例代码中不使用它，即XOR的数据带有寄存器的顶部字节来索引表，deptermess
len是字节和增量的计数p是指向字节的指针：There are typos in that text file. The top byte matters, since each non-zero bit results in the polynomial being xor'ed to the register, and the bits at that point are being shifted to the left. W/4 should be W/8, but it's not used in the later example code that xor's data with the top byte of the register to index the table, decrements
lenwhich is a count of bytes and incrementspwhich is a pointer to a byte: