串口通信字符的轉換

char data[]="CD EF JK 45 23" 其中45 23 轉換爲 17699

過程如下： 

WORD fvalue;
char cdata[2] = {0};
cdata[0] = data[3];
cdata[1] = data[4];
memcpy(&fvalue,cdata,sizeof(fvalue));

char data[]="01 98 8E 44"  轉換爲 float "1140.75"

過程如下

float fvalue ;
byte value[4] = {0};
value[0] = data[1];
value[1] = data[2];
value[2] = data[3];
value[3] = data[4];	
memcpy(&fvalue,value,4);

 串口通信過程

byte Send[8] = {0};
 Send[0] = 0x01
 Send[1] = 0x03;
 Send[2] = 0x00;
 Send[3] = 0x00;
 Send[4] = 0x00;
 Send[5] = 0x10; 
 WORD CRCCode = CheckCode((char*)szSend,6); 
 byte Code[2] = {0};
 memcpy(Code,&CRCCode,sizeof(Code));
 memcpy(&szSend[6],Code,sizeof(Code)); 
 if(this->Write((char*)szSend,sizeof(szSend)))
 {
  if(this->Read(8))
  {}
}

其中 

//獲得CRC校驗碼(此校驗碼爲MODBUS協議的CRC校驗碼)
WORD CheckCode(const char * pSendBuf, int nEnd)
{
	WORD wCrc = WORD(0xFFFF);
	for(int i=0; i<nEnd; i++)	
	{
		
		wCrc ^= WORD(BYTE(pSendBuf[i]));
		for(int j=0; j<8; j++)		
		{
			if(wCrc & 1)		
			{	
				wCrc >>= 1; 		
				wCrc ^= 0xA001; 	
			}
			else	
			{
				wCrc >>= 1; 
			}	
		}	
	}
	return wCrc;

}