二进制数据累加求和,取低八位

V2EX = way to explore

V2EX 是一个关于分享和探索的地方

已注册用户请登录

这是一个创建于 1075 天前的主题，其中的信息可能已经有所发展或是发生改变。

以下是 16 进制表示,我把每一个 16 进制转换成 10 进制,然后进行累加,得到 2551

echo 2551&0xff;

转换成 16 进制是f7

5a 54 08 1f 01 01 61 00 50 53 0a 09 4e 01 64 00 00 00 00 00 00 00 00 00 00 00 00 02 00 00 00 00 00 00 00 00 50 53 0a 09 4f 03 64 00 00 00 00 00 00 00 50 53 0a 09 46 04 64 00 00 00 00 00 00 00 50 53 0a 0a 09 05 64 00 00 00 00 00 00 00 50 53 0a 0a 08 06 64 00 00 00 00 00 00 00 50 53 0a 09 34 07 64 00 00 00 00 00 00 00 50 53 0a 0a 0a 08 64 00 00 00 00 00 00 00

但是硬件那边传过来的求和校验是0x47，是我哪里算错了吗

累加

二进制

x47

xff

4 条回复 • 2021-05-11 11:58:05 +08:00

aa65535

2021-05-10 17:29:57 +08:00

明明加起来是 2631，不知道你为什么能得到 2551

SingeeKing

2021-05-10 17:40:15 +08:00

>>> sum([int(x, 16) for x in '''5a 54 08 1f 01 01 61 00 50 53 0a 09 4e 01 64 00 00 00 00 00 00 00 00 00 00 00 00 02 00 00 00 00 00 00 00 00 50 53 0a 09 4f 03 64 00 00 00 00 00 00 00 50 53 0a 09 46 04 64 00 00 00 00 00 00 00 50 53 0a 0a 09 05 64 00 00 00 00 00 00 00 50 53 0a 0a 08 06 64 00 00 00 00 00 00 00 50 53 0a 09 34 07 64 00 00 00 00 00 00 00 50 53 0a 0a 0a 08 64 00 00 00 00 00 00 00'''.strip().split()])
2631

takitooru

2021-05-11 00:00:38 +08:00

uint8_t test_list[]={0x5a,0x54,0x08,0x1f,0x01,0x01,0x61,0x00,0x50,0x53,0x0a,0x09,0x4e,0x01,0x64,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x02,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x50,0x53,0x0a,0x09,0x4f,0x03,0x64,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x50,0x53,0x0a,0x09,0x46,0x04,0x64,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x50,0x53,0x0a,0x0a,0x09,0x05,0x64,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x50,0x53,0x0a,0x0a,0x08,0x06,0x64,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x50,0x53,0x0a,0x09,0x34,0x07,0x64,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x50,0x53,0x0a,0x0a,0x0a,0x08,0x64,0x00,0x00,0x00,0x00,0x00,0x00,0x00};
int main(int argc,char *argv[])
{
uint8_t rst = 0;
for(int i=0;i<sizeof(test_list);i++)
{
rst += test_list[i];
}
printf("%d 0x%02x",rst,rst);
}
gcc .\test6_sig.c -m32
.\a.exe
-> 71 0x47

cs5117155

2021-05-11 11:58:05 +08:00

谢谢大家，原来我自已程序过滤了一个字节，导致结果错误了，2631 是对的