text: /* Copyright (c) 2012 Nordic Semiconductor. All Rights Reserved.
   *
   * The information contained herein is property of Nordic Semiconductor ASA.
   * Terms and conditions of usage are described in detail in NORDIC
   * SEMICONDUCTOR STANDARD SOFTWARE LICENSE AGREEMENT.
   *
   * Licensees are granted free, non-transferable use of the information. NO
   * WARRANTY of ANY KIND is provided. This heading must NOT be removed from
   * the file.
   *
   */
  
  /** @file
   *
   * @defgroup ble_flash_module Flash Manager
   * @{
   * @ingroup ble_sdk_lib
   * @brief Module for accessing flash memory.
   *
   * @details It contains functions for reading, writing and erasing one page in flash.
   *
   *          The module uses the first 32 bits of the flash page to write a magic number in order to
   *          determine if the page has been written or not.
   *
   * @note Be careful not to use a page number in the SoftDevice area (which currently occupies the
   *       range 0 to 127), or in your application space! In both cases, this would end up
   *       with a hard fault.
   */
  
  #ifndef BLE_FLASH_H__
  #define BLE_FLASH_H__
  
  #include <stdint.h>
  #include <stdbool.h>
  #include "nrf.h"
  
  #define BLE_FLASH_PAGE_SIZE     ((uint16_t)NRF_FICR->CODEPAGESIZE)  /**< Size of one flash page. */
  #define BLE_FLASH_MAGIC_NUMBER  0x45DE0000                          /**< Magic value to identify if flash contains valid data. */
  #define BLE_FLASH_EMPTY_MASK    0xFFFFFFFF                          /**< Bit mask that defines an empty address in flash. */
  
  
  /**@brief Macro for getting the end of the flash available for application.
   * 
   * @details    The result flash page number indicates the end boundary of the flash available 
   *             to the application. If a bootloader is used, the end will be the start of the 
   *             bootloader region. Otherwise, the end will be the size of the flash. 
   */
  #define BLE_FLASH_PAGE_END \
      ((NRF_UICR->NRFFW[0] != BLE_FLASH_EMPTY_MASK) \
          ? (NRF_UICR->NRFFW[0] / BLE_FLASH_PAGE_SIZE) \
          : NRF_FICR->CODESIZE)
  
  /**@brief Function for erasing the specified flash page, and then writes the given data to this page.
   *
   * @warning This operation blocks the CPU. DO NOT use while in a connection!
   *
   * @param[in]  page_num     Page number to update.
   * @param[in]  p_in_array   Pointer to a RAM area containing the elements to write in flash.
   *                          This area has to be 32 bits aligned.
   * @param[in]  word_count   Number of 32 bits words to write in flash.
   *
   * @return     NRF_SUCCESS on successful flash write, otherwise an error code.
   */
  uint32_t ble_flash_page_write(uint8_t page_num, uint32_t * p_in_array, uint8_t word_count);
  
  /**@brief Function for reading data from flash to RAM.
   *
   * @param[in]  page_num       Page number to read.
   * @param[out] p_out_array    Pointer to a RAM area where the found data will be written. 
   *                            This area has to be 32 bits aligned.
   * @param[out] p_word_count   Number of 32 bits words read.
   *
   * @return     NRF_SUCCESS on successful upload, NRF_ERROR_NOT_FOUND if no valid data has been found
   *             in flash (first 32 bits not equal to the MAGIC_NUMBER+CRC).
   */
  uint32_t ble_flash_page_read(uint8_t page_num, uint32_t * p_out_array, uint8_t * p_word_count);
  
  /**@brief Function for erasing a flash page.
   *
   * @note This operation blocks the CPU, so it should not be done while the radio is running!
   *
   * @param[in]  page_num   Page number to erase.
   *
   * @return     NRF_SUCCESS on success, an error_code otherwise.
   */
  uint32_t ble_flash_page_erase(uint8_t page_num);
  
  /**@brief Function for writing one word to flash.
   *
   * @note Flash location to be written must have been erased previously.
   *
   * @param[in]  p_address   Pointer to flash location to be written.
   * @param[in]  value       Value to write to flash.
   *
   * @return     NRF_SUCCESS.
   */
  uint32_t ble_flash_word_write(uint32_t * p_address, uint32_t value);
  
  /**@brief Function for writing a data block to flash.
   *
   * @note Flash locations to be written must have been erased previously.
   *
   * @param[in]  p_address    Pointer to start of flash location to be written.
   * @param[in]  p_in_array   Pointer to start of flash block to be written.
   * @param[in]  word_count   Number of words to be written.
   *
   * @return     NRF_SUCCESS.
   */
  uint32_t ble_flash_block_write(uint32_t * p_address, uint32_t * p_in_array, uint16_t word_count);
  
  /**@brief Function for computing pointer to start of specified flash page.
   *
   * @param[in]  page_num       Page number.
   * @param[out] pp_page_addr   Pointer to start of flash page.
   *
   * @return     NRF_SUCCESS.
   */
  uint32_t ble_flash_page_addr(uint8_t page_num, uint32_t ** pp_page_addr);
  
  /**@brief Function for calculating a 16 bit CRC using the CRC-16-CCITT scheme.
   * 
   * @param[in]  p_data   Pointer to data on which the CRC is to be calulated.
   * @param[in]  size     Number of bytes on which the CRC is to be calulated.
   * @param[in]  p_crc    Initial CRC value (if NULL, a preset value is used as the initial value).
   *
   * @return     Calculated CRC.
   */
  uint16_t ble_flash_crc16_compute(uint8_t * p_data, uint16_t size, uint16_t * p_crc);
  
  /**@brief Function for handling flashing module Radio Notification event.
   *
   * @note For flash writing to work safely while in a connection or while advertising, this function
   *       MUST be called from the Radio Notification module's event handler (see
   *       @ref ble_radio_notification for details).
   *
   * @param[in]  radio_active   TRUE if radio is active (or about to become active), FALSE otherwise.
   */
  void ble_flash_on_radio_active_evt(bool radio_active);
  
  #endif // BLE_FLASH_H__
  
  /** @} */
  