crc.nc

tinyos-2.x.rar

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/**
 * 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);
  
}