STM32CubeF7/Projects/STM32F769I_EVAL/Applications/FatFs/FatFs_USBDisk_MultipleAccess_RTOS

/**
  @page FatFs_USBDisk_MultipleAccess_RTOS   FatFs with USB disk drive multiple access in RTOS mode application

  @verbatim
  ******************************************************************************
  * @file    FatFs/FatFs_USBDisk_MultipleAccess_RTOS/readme.txt
  * @author  MCD Application Team
  * @brief   Description of the FatFs with USB disk drive multiple access in
  *          RTOS mode application
  ******************************************************************************
  *
  * @attention
  *
  * Copyright (c) 2016 STMicroelectronics.
  * All rights reserved.
  *
  * This software is licensed under terms that can be found in the LICENSE file
  * in the root directory of this software component.
  * If no LICENSE file comes with this software, it is provided AS-IS.
  *
  ******************************************************************************
    @endverbatim

@par Application Description

This application provides a description on how to use STM32Cube firmware with FatFs
middleware component as a generic FAT file system module, FreeRTOS as an RTOS
module based on using CMSIS-OS wrapping layer common APIs, and also STM32 USB
On-The-Go (OTG) host library, in Full Speed (FS), High Speed (HS) and High Speed
in Full Speed (HS-IN-FS) modes, in order to develop an application exploiting
FatFs offered features with USB disk drive in RTOS mode configuration.

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. The user is provided with the SystemClock_Config()
function to configure the system clock (SYSCLK) to run at 216 MHz. The Full Speed (FS) USB module uses
internally a 48-MHz clock which is coming from a specific output of two PLLs: main PLL or PLL SAI.
In the High Speed (HS) mode the USB clock (60 MHz) is driven by the ULPI.

The 48 MHz clock for the USB FS can be derived from one of the two following sources:
  – PLL clock (clocked by the HSE): If the USB uses the PLL as clock source, the PLL VCO clock must be programmed
    to output 336 MHz frequency (USBCLK = PLLVCO/PLLQ).
  – PLLSAI clock (clocked by the HSE): If the USB uses the PLLSAI as clock source, the PLLSAI VCO clock must be programmed
    to output 384 MHz frequency (USBCLK = PLLSAIVCO/PLLSAIP).

The application is based on writing two text files to a drive. Two threads, with
different priorities, are created to manage multiple access to the FAT volumes
through FatFs APIs as described in the following steps:

 - StartThread with a normal priority executing steps below:
   - Link the USB Host disk I/O driver;
   - Register the file system object (mount) to the FatFs module for the USB drive;
   - Create and Open new text file object with write access;
   - Write data to the text file;
   - Close the open text file.

 - ConcurrentThread with a high priority executing steps below:
   - Create and Open new text file object with write access;
   - Write data to the text file;
   - Close the open text file;
   - Unlink the USB Host disk I/O driver.

It is worth noting that the application manages any error occurred during the
access to FAT volume, when using FatFs APIs. Otherwise, user can check if the
written text files are available on the USB disk.

It is possible to fine tune needed FatFs features by modifying defines values
in FatFs configuration file “ffconf.h” available under the project includes
directory, in a way to fit the application requirements.

STM32 Eval board's LEDs can be used to monitor the application status:
  - LED1 and LED4 are ON when the application runs successfully.
  - LED3 is ON when any error occurs.

@note The FreeRTOS heap size configTOTAL_HEAP_SIZE defined in FreeRTOSConfig.h is set accordingly to the
      OS resources memory requirements of the application with +10% margin and rounded to the upper Kbyte boundary.

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

@note The application needs to ensure that the HAL time base is always set to 1 millisecond
      to have correct HAL operation.

For more details about FatFs implementation on STM32Cube, please refer to UM1721 "Developing Applications
on STM32Cube with FatFs".


@par Keywords

Connectivity, FatFS, USB_Host, FAT, File system, Full Speed, High Speed, HS-IN-FS,

@Note 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,
      then it is highly recommended to enable the CPU cache and maintain its coherence at application level.
      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
      It is also possible to configure the MPU as "Write through", to guarantee the write access coherence.
      In that case, the MPU must be configured as Cacheable/Bufferable/Not Shareable.
      Even though the user must manage the cache coherence for read accesses.
      Please refer to the AN4838 “Managing memory protection unit (MPU) in STM32 MCUs”
      Please refer to the AN4839 “Level 1 cache on STM32F7 Series”

@par Directory contents

  - FatFs/FatFs_USBDisk_MultipleAccess_RTOS/Inc/stm32f7xx_hal_conf.h              HAL configuration file
  - FatFs/FatFs_USBDisk_MultipleAccess_RTOS/Inc/stm32f7xx_it.h                    Interrupt handlers header file
  - FatFs/FatFs_USBDisk_MultipleAccess_RTOS/Inc/main.h                            Main program header file
  - FatFs/FatFs_USBDisk_MultipleAccess_RTOS/Inc/usbh_diskio.h                     FatFS usb host driver header file
  - FatFs/FatFs_USBDisk_MultipleAccess_RTOS/Inc/ffconf.h                          FAT file system module configuration file
  - FatFs/FatFs_USBDisk_MultipleAccess_RTOS/Inc/FreeRTOSConfig.h                  FreeRTOS distribution file
  - FatFs/FatFs_USBDisk_MultipleAccess_RTOS/Inc/usbh_conf.h                       General low level driver configuration
  - FatFs/FatFs_USBDisk_MultipleAccess_RTOS/Src/stm32f7xx_hal_timebase_tim.c      HAL time base functions
  - FatFs/FatFs_USBDisk_MultipleAccess_RTOS/Src/usbh_conf.c                       USB Host configuration file
  - FatFs/FatFs_USBDisk_MultipleAccess_RTOS/Src/stm32f7xx_it.c                    Interrupt handlers
  - FatFs/FatFs_USBDisk_MultipleAccess_RTOS/Src/main.c                            Main program
  - FatFs/FatFs_USBDisk_MultipleAccess_RTOS/Src/usbh_diskio.c                     FatFS usb host diskio driver implementation
  - FatFs/FatFs_USBDisk_MultipleAccess_RTOS/Src/system_stm32f7xx.c                STM32F7xx system clock configuration file


@par Hardware and Software environment

  - 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.

  - STM32F769I-EVAL Set-up
    - Plug the USB key into the STM32F769I-EVAL board through 'USB micro A-Male
      to A-Female' cable to the connector:
      - CN8 : to use USB High Speed (HS) with embedded PHY(U8)
      - CN13: to use USB Full Speed (FS)
      - CN14: to use USB HS-IN-FS.
              Note that some FS signals are shared with the HS ULPI bus, so some PCB rework is needed.
              For more details, refer to section USB OTG2 HS & FS in STM32F769I-EVAL user manual for details.

@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
 - In the workspace toolbar select the project configuration:
   - STM32F769I-EVAL_USBH-HS: to configure the project for STM32F7xx devices using USB OTG HS peripheral
   - STM32F769I-EVAL_USBH-FS: to configure the project for STM32F7xx devices using USB OTG FS peripheral
   - STM32F769I-EVAL_USBH-HS-IN-FS: to configure the project for STM32F7xx devices and use USB OTG HS
                                   peripheral In FS (using embedded PHY).
 - Run the application


 */