crc.nc

来自「tinyos-2.x.rar」· NC 代码 · 共 56 行

/*                                                                      
 *
 * "Copyright (c) 2000-2007 The Regents of the University of
 * California.  All rights reserved.
 *
 * Permission to use, copy, modify, and distribute this software and
 * its documentation for any purpose, without fee, and without written
 * agreement is hereby granted, provided that the above copyright
 * notice, the following two paragraphs and the author appear in all
 * copies of this software.
 * 
 * IN NO EVENT SHALL THE UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY
 * PARTY FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL
 * DAMAGES ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS
 * DOCUMENTATION, EVEN IF THE UNIVERSITY OF CALIFORNIA HAS BEEN
 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 * 
 * THE UNIVERSITY OF CALIFORNIA SPECIFICALLY DISCLAIMS ANY WARRANTIES,
 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE
 * PROVIDED HEREUNDER IS ON AN "AS IS" BASIS, AND THE UNIVERSITY OF
 * CALIFORNIA HAS NO OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT,
 * UPDATES, ENHANCEMENTS, OR MODIFICATIONS."
 *
 */

/**
 * Compute the CRC-16 value of a byte array.
 *
 * @author Jonathan Hui <[e-mail]>
 * @author David Moss
 */
interface Crc {

  /**
   * Compute the CRC-16 value of a byte array.
   *
   * @param   'void* COUNT(len) buf' A pointer to the buffer over which to compute CRC.
   * @param   len The length of the buffer over which to compute CRC.
   * @return  The CRC-16 value.
   */
  async command uint16_t crc16(void* buf, uint8_t len);
  
  /**
   * Compute a generic CRC-16 using a given seed.  Used to compute CRC's
   * of discontinuous data.
   * 
   * @param startCrc An initial CRC value to begin with
   * @param 'void* COUNT(len) buf' A pointer to a buffer of data
   * @param len The length of the buffer
   * @return The CRC-16 value.
   */
  async command uint16_t seededCrc16(uint16_t startCrc, void *buf, uint8_t len);
  
}