STM32CubeF7/Projects/STM32F769I_EVAL/Applications/FatFs/FatFs_RAMDisk

/**
  @page FatFs_RAMDisk   FatFs with RAM disk drive application
 
  @verbatim
  ******************************************************************************
  * @file    readme.txt
  * @author  MCD Application Team
  * @brief   Description of the FatFs with RAM disk drive application
  ******************************************************************************
  *
  * Copyright (c) 2016 STMicroelectronics International N.V. All rights reserved.
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  * 5. Redistribution and use of this software other than as permitted under 
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  ******************************************************************************
  @endverbatim

@par Application Description

How to use STM32Cube firmware with FatFs middleware component as a generic FAT
file system module. This example develops an application that exploits FatFs
features to configure a RAM disk (SRAM) drive.

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 216 MHz.
 
The application is based on writing and reading back a text file from a drive,
and it's performed using FatFs APIs to access the FAT volume as described
in the following steps:

 - Link the SRAM disk I/O driver;
 - Register the file system object (mount) to the FatFs module for the SRAM drive;
 - Create a FAT file system (format) on the SRAM drive;
 - Create and Open new text file object with write access;
 - Write data to the text file;
 - Close the open text file;
 - Open text file object with read access;
 - Read back data from the text file;
 - Close the open text file;
 - Check on read data from text file;
 - Unlink the SRAM disk I/O driver.

Notice that the application manages possible errors that might occur during the 
access to FAT volume, when using FatFs APIs.

It is possible to fine tune needed FatFs features by modifying defines values 
in FatFs configuration file <20>ffconf.h<> available under the project includes 
directory, in a way to fit the application requirements. 
 
STM32 board's LEDs can be used to monitor the application status:
  - LED1 is ON when the application runs successfully.
  - LED3 is ON when any error occurs. 

@par Keywords

FatFS, RAMDisk, SRAM, FAT, File system, Mount, Format

@Note<74>If the user code size exceeds the DTCM-RAM size or starts from internal cacheable memories (SRAM1 and SRAM2),that is shared between several processors,
 <20><><A0><A0><A0>then it is highly recommended to enable the CPU cache and maintain its coherence at application level.
<0A><><A0><A0><A0><A0>The address and the size of cacheable buffers (shared between CPU and other masters)  must be properly updated to be aligned to cache line size (32 bytes).

@Note It is recommended to enable the cache and maintain its coherence, but depending on the use case
<0A><><A0><A0><A0> It is also possible to configure the MPU as "Write through", to guarantee the write access coherence.
<0A><><A0><A0><A0><A0>In that case, the MPU must be configured as Cacheable/Bufferable/Not Shareable.
<0A><><A0><A0><A0><A0>Even though the user must manage the cache coherence for read accesses.
<0A><><A0><A0><A0><A0>Please refer to the AN4838 <20>Managing memory protection unit (MPU) in STM32 MCUs<55>
<0A><><A0><A0><A0><A0>Please refer to the AN4839 <20>Level 1 cache on STM32F7 Series<65>

@par Directory contents
 
  - FatFs/FatFs_RAMDisk/Inc/stm32f7xx_hal_conf.h    HAL configuration file
  - FatFs/FatFs_RAMDisk/Inc/stm32f7xx_it.h          Interrupt handlers header file
  - FatFs/FatFs_RAMDisk/Inc/main.h                  Header for main.c module
  - FatFs/FatFs_RAMDisk/Inc/ffconf.h                FAT file system module configuration file   
  - FatFs/FatFs_RAMDisk/Inc/sram_diskio.h           SRAM diskio header file
  - FatFs/FatFs_RAMDisk/Src/stm32f7xx_it.c          Interrupt handlers
  - FatFs/FatFs_RAMDisk/Src/main.c                  Main program
  - FatFs/FatFs_RAMDisk/Src/system_stm32f7xx.c      STM32F7xx system source file
  - FatFs/FatFs_RAMDisk/Src/sram_diskio.c           SRAM diskio source file

  - This application runs on STM32F767xx/STM32F769xx/STM32F777xx/STM32F779xx devices.
    
  - This application has been tested with STMicroelectronics STM32F769I-EVAL 
    evaluation boards 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>
 */