crc.h

传感器网络中的嵌入式操作系统源代码

// $Id: crc.h,v 1.1.2.1 2003/08/19 22:12:36 scipio Exp $

/*									tab:4
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 * Copyright (c) 2002-2003 Intel Corporation
 * All rights reserved.
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/* Default CRC function. Note that avrmote has a much more efficient one. */

uint16_t crcByte(uint16_t crc, uint8_t byte)
{
  uint8_t i;
  
  crc = crc ^ byte << 8;
  i = 8;
  do
    if (crc & 0x8000)
      crc = crc << 1 ^ 0x1021;
    else
      crc = crc << 1;
  while (--i);

  return crc;
}