CRC校验

具体原理:

https://blog.csdn.net/resilient/article/details/117368600

Modbus int16 CRC

uint16_t crc16(uint8_t *addr,uint8_t num)
{
  int i,j,temp;
  uint16_t crc=0xFFFF;
  for(i=0;i<num;i++)
  {
    crc=crc^(*addr);
    for(j=0;j<8;j++)
    {
      temp=crc&0x0001;
      crc=crc>>1;
      if(temp)
      {
        crc=crc^0xA001;
      }
    }
    addr++;
  }
  return crc;
}