/**
  @page LwIP_TFTP_Server LwIP TFTP Server application
 
  @verbatim
  ******************** (C) COPYRIGHT 2017 STMicroelectronics *******************
  * @file    LwIP/LwIP_TFTP_Server/Readme.txt
  * @author  MCD Application Team
  * @brief   Description of the LwIP TFTP Server application.
  ******************************************************************************
  * @attention
  *
  * <h2><center>&copy; Copyright © 2017 STMicroelectronics International N.V. 
  * All rights reserved.</center></h2>
  *
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  *    derived from this software without specific written permission.
  * 4. This software, including modifications and/or derivative works of this 
  *    software, must execute solely and exclusively on microcontroller or
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  * 5. Redistribution and use of this software other than as permitted under 
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  ******************************************************************************
   @endverbatim

@par Application Description

This application guides STM32Cube HAL API users to run a tftp server demonstration
for STM32F2xx devices.

User has to use a PC SW tool (ex. TFTPD32) to send/receive data to/from micro SD 
card installed in STM322xG-EVAL board 

If the LCD is used (#define USE_LCD in main.h), log messages will be displayed 
to inform user about ethernet cable status and the IP address value, else this 
will be ensured by LEDs:
  + LED1: ethernet cable is connected.
  + LED2: ethernet cable is not connected.

If a DHCP server is available, a dynamic IP address can be allocated by enabling 
the DHCP process (#define USE_DHCP in main.h) 

The maximum length of filename used to send or to recieve to/from uSD is set to 12 bytes

Note: In this application the Ethernet Link ISR need the HAL time base to configure 
the Ethernet MAC, so the Ethernet Link interrupt priority must be set lower (numerically greater) 
than the HAL tick interrupt priority to ensure that the System tick increments while executing 
the Ethernet Link ISR.

@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.
      
For more details about this application, refer to UM1713 "STM32Cube interfacing with LwIP and applications"


@par Directory contents

    - LwIP/LwIP_TFTP_Server/Inc/app_ethernet.h           header of app_ethernet.c file
    - LwIP/LwIP_TFTP_Server/Inc/ethernetif.h             header for ethernetif.c file
    - LwIP/LwIP_TFTP_Server/Inc/lcd_log_conf.h           LCD Log configuration file
    - LwIP/LwIP_TFTP_Server/Inc/ffconf.h                 FAT file system module configuration file
    - LwIP/LwIP_TFTP_Server/Inc/main.h                   Main program header file
    - LwIP/LwIP_TFTP_Server/Inc/lwipopts.h               LwIP stack configuration options
    - LwIP/LwIP_TFTP_Server/Inc/stm32f2xx_hal_conf.h     HAL Configuration file
    - LwIP/LwIP_TFTP_Server/Inc/stm32f2xx_it.h           header for stm32f2xx_it.c
    - LwIP/LwIP_TFTP_Server/Inc/tftpserver.h             header for tftpserver.c
    - LwIP/LwIP_TFTP_Server/Inc/tftputils.h              header for tftputils.c
    - LwIP/LwIP_TFTP_Server/Src/app_ethernet.c           Ethernet specific module
    - LwIP/LwIP_TFTP_Server/Src/main.c                   Main program  
    - LwIP/LwIP_TFTP_Server/Src/ethernetif.c             Interfacing LwIP to ETH driver
    - LwIP/LwIP_TFTP_Server/Src/system_stm32f2xx.c       STM32 system configuration file
    - LwIP/LwIP_TFTP_Server/Src/stm32f2xx_it.c           Interrupt handlers
    - LwIP/LwIP_TFTP_Server/Src/tftpserver.c             tftp server application
    - LwIP/LwIP_TFTP_Server/Src/tftputils.c              tftp server utilities functions


@par Hardware and Software environment

  - This application runs on STM32F207xx/STM32F217xx Devices.

  - This application has been tested with the following environments:
     - STM322xG-EVAL board
     - TFTP client and DHCP server: PC utility TFTPD32 (http://tftpd32.jounin.net/)
  
  - STM322xG-EVAL Set-up
    - Connect the eval board to remote PC (through a crossover ethernet cable)
      or to your local network (through a straight ethernet cable)
    - JP5 and JP6 jumpers should be fitted in 2-3 position
    
  - Remote PC Set-up
    - Configure a static IP address for your remote PC 
      for example 192.168.0.11 


@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

 * <h2><center>&copy; COPYRIGHT STMicroelectronics</center></h2>
 */
