zuixindaima.cpp

数据传输中的crc交验源代码程序。可实现数据传输过程的crc循环校验功能。

//---------------------------------------------------------------------------

#include <vcl.h>
#pragma hdrstop

#include "zuixindaima.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TForm1 *Form1;
//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
        : TForm(Owner)
{
}
//---------------------------------------------------------------------------


TForm1::CrcCheck(char * fanzc, int Count)
{ 
{
        unsigned char scrch,scrcl,cl,si;
        unsigned char crcdl,crcal;
        unsigned short us;
        
        unsigned char crc_div[64]={0,0,192,193,193,129,1,64,195,1,3,192,2,128,194,65,
                                   198,1,6,192,7,128,199,65,5,0,197,193,196,129,4,64,
		                   0,0,204,1,216,1,20,0,240,1,60,0,40,0,228,1,160,1,
                        	   108,0,120,0,180,1,80,0,156,1,136,1,68,0};

        scrcl=0;
        scrch=0;

        if (Count==0) return 0;

        for(int di=0;di<Count;di++)    // 算命令串校验码.
        {
          crcal= fanzc[di] ^ scrcl;
          crcdl= crcal;
          crcal= crcal & 0x0f;
          crcal= (crcal << 1) + ((crcal & 0x7f) >> 7);
          si= crcal;
          crcal= crcdl;
          cl= crc_div[si];
          crcdl= crc_div[si + 1];
          crcal= (crcal >> 3) + (((crcal & 1) + (crcal & 2) + (crcal & 4)) << 5);
          crcal= (crcal & 30) + 32;
          si= crcal;
          crcal= crc_div[si] ^ cl;
          cl= crcal;
          crcal= crc_div[si + 1];
          crcdl= crcal ^ crcdl;
          crcal= cl ^ scrch;
          scrch= crcdl;
          scrcl= crcal;
        }
        us = (scrch << 8) + scrcl;
        return us;
}


}
void __fastcall TForm1::Button1Click(TObject *Sender)
{ unsigned char a[8]={ 0x00,0x00,0x00,0x00,0x06,0x0d,0xd2,0xe3};
Edit1->Text=CrcCheck(a,8);
}
//---------------------------------------------------------------------------