/* ----------------------------------------------------------------------------
 *         ATMEL Microcontroller Software Support
 * ----------------------------------------------------------------------------
 * Copyright (c) 2015, Atmel Corporation
 *
 * All rights reserved.
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#ifndef _HAMMING_
#define _HAMMING_

#include <stdint.h>

/*------------------------------------------------------------------------------
 *         Defines
 *------------------------------------------------------------------------------*/

/**
 *  These are the possible errors when trying to verify a block of data encoded
 *  using a Hamming code:
 *
 *  \section Errors
 *   - HAMMING_ERROR_SINGLEBIT
 *   - HAMMING_ERROR_ECC
 *   - HAMMING_ERROR_MULTIPLEBITS
 */

/**  A single bit was incorrect but has been recovered. */
#define HAMMING_ERROR_SINGLEBIT         1

/** The original code has been corrupted. */
#define HAMMING_ERROR_ECC               2

/** Multiple bits are incorrect in the data and they cannot be corrected. */
#define HAMMING_ERROR_MULTIPLEBITS      3

/*------------------------------------------------------------------------------
 *         Exported functions
 *------------------------------------------------------------------------------*/

void hamming_compute_256x(const uint8_t *data, uint32_t size, uint8_t *code);

extern uint8_t hamming_verify_256x(uint8_t *data, uint32_t size,
		const uint8_t *code);

#endif /* _HAMMING_ */