/**
  @page FLASH_EraseProgram FLASH Erase and Program application
  
  @verbatim
  ******************** (C) COPYRIGHT 2016 STMicroelectronics *******************
  * @file    FLASH/FLASH_EraseProgram/readme.txt
  * @author  MCD Application Team
  * @brief   Description of the FLASH Erase and Program example.
  ******************************************************************************
  * @attention
  *
  * <h2><center>&copy; Copyright (c) 2016 STMicroelectronics.
  * All rights reserved.</center></h2>
  *
  * This software component is licensed by ST under BSD 3-Clause license,
  * the "License"; You may not use this file except in compliance with the
  * License. You may obtain a copy of the License at:
  *                        opensource.org/licenses/BSD-3-Clause
  *
  ******************************************************************************
  @endverbatim

@par Application Description 

How to configure and use the FLASH HAL API to erase and program the internal
Flash memory.
  
At the beginning of the main program the HAL_Init() function is called to reset 
all the peripherals, initialize the Flash interface and the systick.
Then the SystemClock_Config() function is used to configure the system clock (SYSCLK) 
to run at 48 MHz. 

After Reset, the Flash memory Program/Erase Controller is locked. A dedicated function
is used to enable the FLASH control register access.
Before programming the desired addresses, an erase operation is performed using 
the flash erase page feature. The erase procedure is done by filling the erase init 
structure giving the starting erase page and the number of pages to erase.
At this stage, all these pages will be erased one by one separately.

@note: if problem occurs on a page, erase will be stopped and faulty page will 
be returned to user (through variable 'pageError').

Once this operation is finished, page word programming operation will be performed 
in the Flash memory. The written data is then read back and checked.

The STM32F042K6-Nucleo(revC) board LEDs can be used to monitor the transfer status:
 - LED3 is ON when there are no errors detected after programmation
 - LED3 is blinking with a 1s period when there are errors dectected after programmation
 - LED3 is blinking (100ms on, 2s off) when there is an issue during erase or program procedure

@note Care must be taken when using HAL_Delay(), this function provides accurate delay (in milliseconds)
      based on variable incremented in SysTick ISR. This implies that if HAL_Delay() is called from
      a peripheral ISR process, then the SysTick interrupt must have higher priority (numerically lower)
      than the peripheral interrupt. Otherwise the caller ISR process will be blocked.
      To change the SysTick interrupt priority you have to use HAL_NVIC_SetPriority() function.
      
@note The application needs to ensure that the SysTick time base is always set to 1 millisecond
      to have correct HAL operation.

@par Directory contents 

  - FLASH/FLASH_EraseProgram/Inc/stm32f0xx_hal_conf.h        HAL Configuration file  
  - FLASH/FLASH_EraseProgram/Inc/stm32f0xx_it.h              Header for stm32f0xx_it.c
  - FLASH/FLASH_EraseProgram/Inc/main.h                      Header for main.c module 
  - FLASH/FLASH_EraseProgram/Src/stm32f0xx_it.c              Interrupt handlers
  - FLASH/FLASH_EraseProgram/Src/main.c                      Main program
  - FLASH/FLASH_EraseProgram/Src/system_stm32f0xx.c          STM32F0xx system clock configuration file

@par Hardware and Software environment

  - This application runs on STM32F042x6 devices.
    
  - This application has been tested with STM32F042K6-Nucleo(revC) board and can be
    easily tailored to any other supported device and development board.
      
@par How to use it ? 

In order to make the program work, you must do the following:
 - Open your preferred toolchain 
 - Rebuild all files and load your image into target memory
 - Run the application


 * <h3><center>&copy; COPYRIGHT STMicroelectronics</center></h3>
 */
