#include "common.h"
// Crc16 校验表
const UINT16 Crc16Table[ 256 ] =
{
0, 4129, 8258,12387,16516,20645,24774,28903,
33032,37161,41290,45419,49548,53677,57806,61935,
4657, 528,12915, 8786,21173,17044,29431,25302,
37689,33560,45947,41818,54205,50076,62463,58334,
9314,13379, 1056, 5121,25830,29895,17572,21637,
42346,46411,34088,38153,58862,62927,50604,54669,
13907, 9842, 5649, 1584,30423,26358,22165,18100,
46939,42874,38681,34616,63455,59390,55197,51132,
18628,22757,26758,30887, 2112, 6241,10242,14371,
51660,55789,59790,63919,35144,39273,43274,47403,
23285,19156,31415,27286, 6769, 2640,14899,10770,
56317,52188,64447,60318,39801,35672,47931,43802,
27814,31879,19684,23749,11298,15363, 3168, 7233,
60846,64911,52716,56781,44330,48395,36200,40265,
32407,28342,24277,20212,15891,11826, 7761, 3696,
65439,61374,57309,53244,48923,44858,40793,36728,
37256,33193,45514,41451,53516,49453,61774,57711,
4224, 161,12482, 8419,20484,16421,28742,24679,
33721,37784,41979,46042,49981,54044,58239,62302,
689, 4752, 8947,13010,16949,21012,25207,29270,
46570,42443,38312,34185,62830,58703,54572,50445,
13538, 9411, 5280, 1153,29798,25671,21540,17413,
42971,47098,34713,38840,59231,63358,50973,55100,
9939,14066, 1681, 5808,26199,30326,17941,22068,
55628,51565,63758,59695,39368,35305,47498,43435,
22596,18533,30726,26663, 6336, 2273,14466,10403,
52093,56156,60223,64286,35833,39896,43963,48026,
19061,23124,27191,31254, 2801, 6864,10931,14994,
64814,60687,56684,52557,48554,44427,40424,36297,
31782,27655,23652,19525,15522,11395, 7392, 3265,
61215,65342,53085,57212,44955,49082,36825,40952,
28183,32310,20053,24180,11923,16050, 3793, 7920
};
/**********************************************************************************
** 功能说明：计算CRC16的校验和(低字节在前)
** 参数列表：IN const char *pBuff: 计算校验和的目标数据块指针
** IN const unsigned long buffLen: 计算校验和的目标数据块大小
** OUT char *pCheckSum: 计算结果数据块指针
** 返 回 值：int
** 0: 成功
** -1: 失败
***********************************************************************************/
int CalcCRC16( const UINT8 *pBuff, const UINT32 buffLen, UINT8 *pCheckSum )
{
UINT32 i = 0;
UINT16 checkSum = 0;
if ( pBuff == NULL || buffLen == 0 || pCheckSum == NULL )
{
return -1;
}
for( i = 0; i < buffLen; i++ )
{
checkSum = ( checkSum << 8 ) ^ Crc16Table[ ( checkSum >> 8 ) ^ pBuff[ i ] ];
}
pCheckSum[ 0 ] = checkSum % 256;
pCheckSum[ 1 ] = checkSum / 256;
return 0;
}
