數(shù)據(jù)安全很重要，如何保證數(shù)據(jù)的有效性？嵌入式常用的校驗算法介紹

    

     uint8_t CheckSum(uint8_t *Buf, uint8_t Len)
     {
     uint8_t i = 0;
     uint8_t sum = 0;
     uint8_t?checksum?=?0;
     for(i=0; i
      {
      sum += *Buf++;
     ??}
     ??checksum?=?sum?&?0xff;
     return checksum;
     }
    

    

     uint8_t CheckXOR(uint8_t *Buf, uint8_t Len)
     {
     uint8_t i = 0;
     uint8_t?x?=?0;
     for(i=0; i
      {
      x = x^(*(Buf+i));
     ??}
     return x;
     }
    

    

     uint8_t CRCTAB_H[256] = {/*表省略*/};
     uint8_t CRCTAB_L[256] = {/*表省略*/};
     void CRC16(uint8_t *pData, uint8_t Len, uint8_t *CRC_H, uint8_t *CRC_L)
     {
     uint8_t i;
     uint8_t index;
     uint8_t crc_h = 0xFF;
     uint8_t??crc_l?=?0xFF;
     for(i=0; i
      {
      index = crc_h^*(pData + i);
      crc_h = crc_l^CRCTAB_H[index];
      crc_l = CRCTAB_L[index];
     ??}
      *CRC_H = crc_h;
      *CRC_L = crc_l;
     }