Files
HBshuiwuConcentrator/yw/crc.c
2025-12-15 16:07:49 +08:00

48 lines
724 B
C

#include "stdafx.h"
#include "crc.h"
/*
static u16 crc16(unsigned char *buf,unsigned short length)
{
int i = 0;
int j = 0;
int crc16 = 0xffff;
for (i = 0;i < length;i++)
{
crc16 = crc16 ^ buf[i];
for (j = 0;j < 8;j++)
{
if (crc16 & 0x01)
{
crc16 = (crc16 >> 1) ^ 0xa001;
}
else
{
crc16 = crc16 >> 1;
}
}
}
return (u16)crc16;
}
*/
static unsigned int cal_crc16(unsigned char *ptr, unsigned int len)
{
unsigned int crc;
unsigned char i;
crc=0xffff;
while(len--!=0) {
crc = crc^(*ptr);
for(i=0; i<8; i++) {
if((crc&0x0001)==0x0001) {crc>>=1;crc^=0xA001;}
else crc>>=1;
}
ptr++;
}
return(crc);
}
u16 get_crc(u8 * val,u16 len)
{
return cal_crc16(val,len);
}