#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);
}