Python 中使用 8 位无符号算术的校验和
Checksum using 8 bit unsigned arithmetic in Python
我正忙着为我的串行数据导出校验和。我以字节形式接收数据，删除标志和转义字符，将其放入列表中。指令文档用图形指定校验和在数据结构的末尾。校验和是通过使用 8 位无符号算法对记录中的所有字节求和来计算的。不幸的是，我有一个巨大的数据文件：
[198, 2, 180, 4, 0, 0, 224, 253, 156, 94, 0, 0, 0, 0, 0, 0, 0, 0, 1, 22, 1, 1, 44, 2, 4, 189, 189, 255, 189, 189, 189, 189, 189, 189, 189, 189, 189, 189, 189, 189, 224, 253, 156, 94, 51, 58, 0, 0, 0, 18, 2, 128, 10, 129, 1, 128, 1, 128, 1, 128, 1, 0, 0, 0, 1, 0, 2, 128, 2, 128, 2, 128, 1, 128, 1, 0, 0, 0, 2, 0, 2, 128, 2, 128, 2, 128, 1, 128, 0, 0, 0, 0, 11, 0, 1, 128, 1, 128, 1, 128, 1, 128, 0, 0, 0, 0, 3, 0, 1, 128, 1, 128, 1, 128, 1, 128, 3, 0, 0, 0, 3, 1, 1, 128, 1, 128, 1, 128, 1, 128, 3, 0, 0, 0, 11, 0, 4, 128, 3, 0, 0, 0, 12, 0, 4, 128, 0, 0, 0, 0, 13, 0, 1, 128, 0, 0, 0, 0, 14, 0, 1, 128, 3, 0, 0, 0, 0, 0, 1, 128, 2, 128, 2, 128, 1, 128, 7, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 203, 29, 3, 0, 0, 0, 0, 0, 38, 8, 38, 8, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 0, 1, 0, 1, 128, 1, 128, 1, 128, 1, 128, 1, 128, 1, 128, 1, 128, 1, 128, 0, 0, 0, 0, 11, 0, 1, 128, 1, 128, 1, 128, 1, 128, 32, 0, 0, 0, 0, 0, 1, 128, 1, 128, 255, 141, 2, 128, 1, 128, 1, 128, 0, 0, 0, 0, 173, 1, 1, 128, 0, 0, 0, 0, 13, 0, 1, 128, 1, 128, 1, 128, 1, 128, 0, 0, 0, 0, 14, 0, 1, 128, 1, 128, 1, 128, 1, 128, 0, 0, 0, 0, 65, 0, 224, 253, 156, 94, 0, 0, 0, 0, 18, 2, 1, 128, 1, 128, 1, 128, 1, 128, 3, 0, 0, 0, 0, 0, 1, 128, 1, 128, 4, 128, 1, 128, 1, 128, 1, 128, 73, 13, 0, 0, 176, 192, 0, 0, 226, 1, 0, 0, 198, 2, 0, 0, 240, 127, 170, 1, 0, 0, 0, 0, 9, 49, 28, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 65, 3, 0, 0, 0, 0, 0, 0, 0, 0, 195, 165, 0, 0, 195, 165, 1, 128, 72, 8, 160, 15, 32, 78, 208, 7, 208, 7, 112, 23, 80, 5, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 4, 0, 0, 0, 4, 0, 0, 0, 2, 0, 0, 0, 1, 0, 0, 0, 0, 0, 52, 8, 0, 0, 0, 0, 208, 7, 112, 23, 17, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 178]
最后一个十六进制数是 178 (0xB2)，我假设它是校验和。当我应用我在网上找到的校验和代码时，它简单地将所有远远超过“178”的整数相加。谁能指出我正确的方向？谢谢
你可以只使用：
l = [198, 2, 180, 4, 0, 0, 224, 253, 156, 94, 0, 0, 0, 0, 0, 0, 0, 0, 1, 22, 1, 1, 44, 2, 4, 189, 189, 255, 189, 189, 189, 189, 189, 189, 189, 189, 189, 189, 189, 189, 224, 253, 156, 94, 51, 58, 0, 0, 0, 18, 2, 128, 10, 129, 1, 128, 1, 128, 1, 128, 1, 0, 0, 0, 1, 0, 2, 128, 2, 128, 2, 128, 1, 128, 1, 0, 0, 0, 2, 0, 2, 128, 2, 128, 2, 128, 1, 128, 0, 0, 0, 0, 11, 0, 1, 128, 1, 128, 1, 128, 1, 128, 0, 0, 0, 0, 3, 0, 1, 128, 1, 128, 1, 128, 1, 128, 3, 0, 0, 0, 3, 1, 1, 128, 1, 128, 1, 128, 1, 128, 3, 0, 0, 0, 11, 0, 4, 128, 3, 0, 0, 0, 12, 0, 4, 128, 0, 0, 0, 0, 13, 0, 1, 128, 0, 0, 0, 0, 14, 0, 1, 128, 3, 0, 0, 0, 0, 0, 1, 128, 2, 128, 2, 128, 1, 128, 7, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 203, 29, 3, 0, 0, 0, 0, 0, 38, 8, 38, 8, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 0, 1, 0, 1, 128, 1, 128, 1, 128, 1, 128, 1, 128, 1, 128, 1, 128, 1, 128, 0, 0, 0, 0, 11, 0, 1, 128, 1, 128, 1, 128, 1, 128, 32, 0, 0, 0, 0, 0, 1, 128, 1, 128, 255, 141, 2, 128, 1, 128, 1, 128, 0, 0, 0, 0, 173, 1, 1, 128, 0, 0, 0, 0, 13, 0, 1, 128, 1, 128, 1, 128, 1, 128, 0, 0, 0, 0, 14, 0, 1, 128, 1, 128, 1, 128, 1, 128, 0, 0, 0, 0, 65, 0, 224, 253, 156, 94, 0, 0, 0, 0, 18, 2, 1, 128, 1, 128, 1, 128, 1, 128, 3, 0, 0, 0, 0, 0, 1, 128, 1, 128, 4, 128, 1, 128, 1, 128, 1, 128, 73, 13, 0, 0, 176, 192, 0, 0, 226, 1, 0, 0, 198, 2, 0, 0, 240, 127, 170, 1, 0, 0, 0, 0, 9, 49, 28, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 65, 3, 0, 0, 0, 0, 0, 0, 0, 0, 195, 165, 0, 0, 195, 165, 1, 128, 72, 8, 160, 15, 32, 78, 208, 7, 208, 7, 112, 23, 80, 5, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 4, 0, 0, 0, 4, 0, 0, 0, 2, 0, 0, 0, 1, 0, 0, 0, 0, 0, 52, 8, 0, 0, 0, 0, 208, 7, 112, 23, 17, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 178]
sum(l[:-1]) & 255
输出：
178
二进制和中发生 8 位溢出，因此您只保留总和中的最后 8 位
我正忙着为我的串行数据导出校验和。我以字节形式接收数据，删除标志和转义字符，将其放入列表中。指令文档用图形指定校验和在数据结构的末尾。校验和是通过使用 8 位无符号算法对记录中的所有字节求和来计算的。不幸的是，我有一个巨大的数据文件：
[198, 2, 180, 4, 0, 0, 224, 253, 156, 94, 0, 0, 0, 0, 0, 0, 0, 0, 1, 22, 1, 1, 44, 2, 4, 189, 189, 255, 189, 189, 189, 189, 189, 189, 189, 189, 189, 189, 189, 189, 224, 253, 156, 94, 51, 58, 0, 0, 0, 18, 2, 128, 10, 129, 1, 128, 1, 128, 1, 128, 1, 0, 0, 0, 1, 0, 2, 128, 2, 128, 2, 128, 1, 128, 1, 0, 0, 0, 2, 0, 2, 128, 2, 128, 2, 128, 1, 128, 0, 0, 0, 0, 11, 0, 1, 128, 1, 128, 1, 128, 1, 128, 0, 0, 0, 0, 3, 0, 1, 128, 1, 128, 1, 128, 1, 128, 3, 0, 0, 0, 3, 1, 1, 128, 1, 128, 1, 128, 1, 128, 3, 0, 0, 0, 11, 0, 4, 128, 3, 0, 0, 0, 12, 0, 4, 128, 0, 0, 0, 0, 13, 0, 1, 128, 0, 0, 0, 0, 14, 0, 1, 128, 3, 0, 0, 0, 0, 0, 1, 128, 2, 128, 2, 128, 1, 128, 7, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 203, 29, 3, 0, 0, 0, 0, 0, 38, 8, 38, 8, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 0, 1, 0, 1, 128, 1, 128, 1, 128, 1, 128, 1, 128, 1, 128, 1, 128, 1, 128, 0, 0, 0, 0, 11, 0, 1, 128, 1, 128, 1, 128, 1, 128, 32, 0, 0, 0, 0, 0, 1, 128, 1, 128, 255, 141, 2, 128, 1, 128, 1, 128, 0, 0, 0, 0, 173, 1, 1, 128, 0, 0, 0, 0, 13, 0, 1, 128, 1, 128, 1, 128, 1, 128, 0, 0, 0, 0, 14, 0, 1, 128, 1, 128, 1, 128, 1, 128, 0, 0, 0, 0, 65, 0, 224, 253, 156, 94, 0, 0, 0, 0, 18, 2, 1, 128, 1, 128, 1, 128, 1, 128, 3, 0, 0, 0, 0, 0, 1, 128, 1, 128, 4, 128, 1, 128, 1, 128, 1, 128, 73, 13, 0, 0, 176, 192, 0, 0, 226, 1, 0, 0, 198, 2, 0, 0, 240, 127, 170, 1, 0, 0, 0, 0, 9, 49, 28, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 65, 3, 0, 0, 0, 0, 0, 0, 0, 0, 195, 165, 0, 0, 195, 165, 1, 128, 72, 8, 160, 15, 32, 78, 208, 7, 208, 7, 112, 23, 80, 5, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 4, 0, 0, 0, 4, 0, 0, 0, 2, 0, 0, 0, 1, 0, 0, 0, 0, 0, 52, 8, 0, 0, 0, 0, 208, 7, 112, 23, 17, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 178]
最后一个十六进制数是 178 (0xB2)，我假设它是校验和。当我应用我在网上找到的校验和代码时，它简单地将所有远远超过“178”的整数相加。谁能指出我正确的方向？谢谢
你可以只使用：
l = [198, 2, 180, 4, 0, 0, 224, 253, 156, 94, 0, 0, 0, 0, 0, 0, 0, 0, 1, 22, 1, 1, 44, 2, 4, 189, 189, 255, 189, 189, 189, 189, 189, 189, 189, 189, 189, 189, 189, 189, 224, 253, 156, 94, 51, 58, 0, 0, 0, 18, 2, 128, 10, 129, 1, 128, 1, 128, 1, 128, 1, 0, 0, 0, 1, 0, 2, 128, 2, 128, 2, 128, 1, 128, 1, 0, 0, 0, 2, 0, 2, 128, 2, 128, 2, 128, 1, 128, 0, 0, 0, 0, 11, 0, 1, 128, 1, 128, 1, 128, 1, 128, 0, 0, 0, 0, 3, 0, 1, 128, 1, 128, 1, 128, 1, 128, 3, 0, 0, 0, 3, 1, 1, 128, 1, 128, 1, 128, 1, 128, 3, 0, 0, 0, 11, 0, 4, 128, 3, 0, 0, 0, 12, 0, 4, 128, 0, 0, 0, 0, 13, 0, 1, 128, 0, 0, 0, 0, 14, 0, 1, 128, 3, 0, 0, 0, 0, 0, 1, 128, 2, 128, 2, 128, 1, 128, 7, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 203, 29, 3, 0, 0, 0, 0, 0, 38, 8, 38, 8, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 0, 1, 0, 1, 128, 1, 128, 1, 128, 1, 128, 1, 128, 1, 128, 1, 128, 1, 128, 0, 0, 0, 0, 11, 0, 1, 128, 1, 128, 1, 128, 1, 128, 32, 0, 0, 0, 0, 0, 1, 128, 1, 128, 255, 141, 2, 128, 1, 128, 1, 128, 0, 0, 0, 0, 173, 1, 1, 128, 0, 0, 0, 0, 13, 0, 1, 128, 1, 128, 1, 128, 1, 128, 0, 0, 0, 0, 14, 0, 1, 128, 1, 128, 1, 128, 1, 128, 0, 0, 0, 0, 65, 0, 224, 253, 156, 94, 0, 0, 0, 0, 18, 2, 1, 128, 1, 128, 1, 128, 1, 128, 3, 0, 0, 0, 0, 0, 1, 128, 1, 128, 4, 128, 1, 128, 1, 128, 1, 128, 73, 13, 0, 0, 176, 192, 0, 0, 226, 1, 0, 0, 198, 2, 0, 0, 240, 127, 170, 1, 0, 0, 0, 0, 9, 49, 28, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 65, 3, 0, 0, 0, 0, 0, 0, 0, 0, 195, 165, 0, 0, 195, 165, 1, 128, 72, 8, 160, 15, 32, 78, 208, 7, 208, 7, 112, 23, 80, 5, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 4, 0, 0, 0, 4, 0, 0, 0, 2, 0, 0, 0, 1, 0, 0, 0, 0, 0, 52, 8, 0, 0, 0, 0, 208, 7, 112, 23, 17, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 178]
sum(l[:-1]) & 255
输出：
178
二进制和中发生 8 位溢出，因此您只保留总和中的最后 8 位