www.pudn.com > rs232_moni.rar > CheckSum.cpp

#include "stdafx.h" 
#include "CheckSum.h" 
 
#define CHECKVALUE(pt,nl)	if((btData==NULL)||(nLength<=0)){AfxMessageBox("无效数组！");return -1;} 
 
CCheckSum::CCheckSum() 
{ 
 
} 
 
CCheckSum::~CCheckSum() 
{ 
 
} 
//CCITT V.41,x16 + x12 + x5 + 1 
WORD CCheckSum::CCITT_CRC_16(BYTE* btData,int nLength) 
{ 
	CHECKVALUE(btData,nLength); 
	WORD CRC=0; 
	BYTE j; 
	int i; 
 
    for(i=0;i>8)+(CRC<<8));/* 应用时低在先 */ 
} 
//ANSI CRC-16,x16 + x15 + x2 + 1 
WORD CCheckSum::ANSI_CRC_16(BYTE* btData,int nLength) 
{ 
	CHECKVALUE(btData,nLength); 
	WORD CRC=0xFFFF; 
	BYTE j,Tmp=0; 
	int i; 
 
    for(i=0;i>1;                 	 
			if(Tmp)CRC=(CRC^0xA001);    	 
		}                                   	 
    } 
	return ((CRC>>8)+(CRC<<8));	/* 应用时高在先 */ 
} 
 
BYTE CCheckSum::CCITT_CRC_8(BYTE* btData,int nLength) 
{ 
	CHECKVALUE(btData,nLength); 
	BYTE CRC=0,j; 
	int i; 
 
    for(i=0;i