几种常用CRC16校验

void InvertUint8(unsigned char *dBuf,unsigned char *srcBuf)
{
int i;
unsigned char tmp[4];
tmp[0] = 0;
for (i=0; i< 8; i++)
{
if (srcBuf[0]& (1 << i)) tmp[0]|=1<<(7-i);
}
dBuf[0] = tmp[0];
}

void InvertUint16(unsigned short *dBuf,unsigned short *srcBuf)
{
int i;
unsigned short tmp[4];
tmp[0] = 0;
for (i=0; i< 16; i++)
{
if (srcBuf[0]& (1 << i)) tmp[0]|=1<<(15 - i);
}
dBuf[0] = tmp[0];
}

unsigned short CRC16_CCITT(unsigned char *puchMsg, unsigned int usDataLen)
{
unsigned short wCRCin = 0x0000;
unsigned short wCPoly = 0x1021;
unsigned char wChar = 0;
while (usDataLen–)
{
wChar = *(puchMsg++);
InvertUint8(&wChar,&wChar);
wCRCin ^= (wChar << 8);
for(int i = 0; i < 8; i++)
{
if(wCRCin & 0x8000) wCRCin = (wCRCin << 1) ^ wCPoly;
else wCRCin = wCRCin << 1;
}
}
InvertUint16(&wCRCin,&wCRCin);
return (wCRCin) ;
}

unsigned short CRC16_CCITT_FALSE(unsigned char *puchMsg, unsigned int usDataLen)
{
unsigned short wCRCin = 0xFFFF;
unsigned short wCPoly = 0x1021;
unsigned char wChar = 0;
while (usDataLen–)
{
wChar = *(puchMsg++);
wCRCin ^= (wChar << 8);
for(int i = 0; i < 8; i++)
{
if(wCRCin & 0x8000) wCRCin = (wCRCin << 1) ^ wCPoly;
else wCRCin = wCRCin << 1;
}
}
return (wCRCin) ;
}

unsigned short CRC16_XMODEM(unsigned char *puchMsg, unsigned int usDataLen)
{
unsigned short wCRCin = 0x0000;
unsigned short wCPoly = 0x1021;
unsigned char wChar = 0;
while (usDataLen–)
{
wChar = *(puchMsg++);
wCRCin ^= (wChar << 8);
for(int i = 0; i < 8; i++)
{
if(wCRCin & 0x8000) wCRCin = (wCRCin << 1) ^ wCPoly;
else wCRCin = wCRCin << 1;
}
}
return (wCRCin) ;
}

unsigned short CRC16_X25(unsigned char *puchMsg, unsigned int usDataLen)
{
unsigned short wCRCin = 0xFFFF;
unsigned short wCPoly = 0x1021;
unsigned char wChar = 0;
while (usDataLen–)
{
wChar = *(puchMsg++);
InvertUint8(&wChar,&wChar);
wCRCin ^= (wChar << 8);
for(int i = 0; i < 8; i++)
{
if(wCRCin & 0x8000) wCRCin = (wCRCin << 1) ^ wCPoly;
else wCRCin = wCRCin << 1;
}
}
InvertUint16(&wCRCin,&wCRCin);
return (wCRCin^0xFFFF) ;
}

unsigned short CRC16_MODBUS(unsigned char *puchMsg, unsigned int usDataLen)
{
unsigned short wCRCin = 0xFFFF;
unsigned short wCPoly = 0x8005;
unsigned char wChar = 0;
while (usDataLen–)
{
wChar = *(puchMsg++);
InvertUint8(&wChar,&wChar);
wCRCin ^= (wChar << 8);
for(int i = 0; i < 8; i++)
{
if(wCRCin & 0x8000) wCRCin = (wCRCin << 1) ^ wCPoly;
else wCRCin = wCRCin << 1;
}
}
InvertUint16(&wCRCin,&wCRCin);
return (wCRCin) ;
}

unsigned short CRC16_IBM(unsigned char *puchMsg, unsigned int usDataLen)
{
unsigned short wCRCin = 0x0000;
unsigned short wCPoly = 0x8005;
unsigned char wChar = 0;
while (usDataLen–)
{
wChar = *(puchMsg++);
InvertUint8(&wChar,&wChar);
wCRCin ^= (wChar << 8);
for(int i = 0; i < 8; i++)
{
if(wCRCin & 0x8000) wCRCin = (wCRCin << 1) ^ wCPoly;
else wCRCin = wCRCin << 1;
}
}
InvertUint16(&wCRCin,&wCRCin);
return (wCRCin) ;
}

unsigned short CRC16_MAXIM(unsigned char *puchMsg, unsigned int usDataLen)
{
unsigned short wCRCin = 0x0000;
unsigned short wCPoly = 0x8005;
unsigned char wChar = 0;
while (usDataLen–)
{
wChar = *(puchMsg++);
InvertUint8(&wChar,&wChar);
wCRCin ^= (wChar << 8);
for(int i = 0; i < 8; i++)
{
if(wCRCin & 0x8000) wCRCin = (wCRCin << 1) ^ wCPoly;
else wCRCin = wCRCin << 1;
}
}
InvertUint16(&wCRCin,&wCRCin);
return (wCRCin^0xFFFF) ;
}

unsigned short CRC16_USB(unsigned char *puchMsg, unsigned int usDataLen)
{
unsigned short wCRCin = 0xFFFF;
unsigned short wCPoly = 0x8005;
unsigned char wChar = 0;
while (usDataLen–)
{
wChar = *(puchMsg++);
InvertUint8(&wChar,&wChar);
wCRCin ^= (wChar << 8);
for(int i = 0; i < 8; i++)
{
if(wCRCin & 0x8000) wCRCin = (wCRCin << 1) ^ wCPoly;
else wCRCin = wCRCin << 1;
}
}
InvertUint16(&wCRCin,&wCRCin);
return (wCRCin^0xFFFF) ;
}