/**
  @page LwIP_TCP_Echo_Server LwIP TCP Echo Server example
  
  @verbatim
  ******************** (C) COPYRIGHT 2016 STMicroelectronics *******************
  * @file    LwIP/LwIP_TCP_Echo_Server/readme.txt 
  * @author  MCD Application Team
  * @version V1.6.0
  * @date    12-May-2017
  * @brief   Description of the LwIP TCP Echo Server example.
  ******************************************************************************
  * @attention
  *
  * <h2><center>&copy; Copyright © 2016 STMicroelectronics International N.V. 
  * All rights reserved.</center></h2>
  *
  * Redistribution and use in source and binary forms, with or without 
  * modification, are permitted, provided that the following conditions are met:
  *
  * 1. Redistribution of source code must retain the above copyright notice, 
  *    this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright notice,
  *    this list of conditions and the following disclaimer in the documentation
  *    and/or other materials provided with the distribution.
  * 3. Neither the name of STMicroelectronics nor the names of other 
  *    contributors to this software may be used to endorse or promote products 
  *    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
  *    microprocessor devices manufactured by or for STMicroelectronics.
  * 5. Redistribution and use of this software other than as permitted under 
  *    this license is void and will automatically terminate your rights under 
  *    this license. 
  *
  * THIS SOFTWARE IS PROVIDED BY STMICROELECTRONICS AND CONTRIBUTORS "AS IS" 
  * AND ANY EXPRESS, IMPLIED OR STATUTORY WARRANTIES, INCLUDING, BUT NOT 
  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A 
  * PARTICULAR PURPOSE AND NON-INFRINGEMENT OF THIRD PARTY INTELLECTUAL PROPERTY
  * RIGHTS ARE DISCLAIMED TO THE FULLEST EXTENT PERMITTED BY LAW. IN NO EVENT 
  * SHALL STMICROELECTRONICS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, 
  * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 
  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 
  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
  * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  *
  ******************************************************************************
  @endverbatim

@par Application Description 

This application shows how to run TCP Echo Server
application based on Raw API of LwIP TCP/IP stack.

To run this application, On the remote PC, open a command prompt window.
(In Windows, select Start > All Programs > Accessories > Command Prompt.)
At the command prompt, enter:
  C:\>echotool IP_address /p tcp /r 7 /n 15 /t 2 /d Testing LwIP TCP echo server

where:
     IP_address is the actual boards IP address. By default, the following 
    static IP address is used: 192.168.0.10
     /p transport layer protocol used for communication (TCP)
     /r is the actual remote port on the echo server (echo port)
     /n is the number of echo requests (for example, 15)
     /t is the connection timeout in seconds (for example, 2)
     /d is the message to be sent for echo 

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)

@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_TCP_Echo_Server/Inc/app_ethernet.h          header of app_ethernet.c file
  - LwIP/LwIP_TCP_Echo_Server/Inc/ethernetif.h            header for ethernetif.c file
  - LwIP/LwIP_TCP_Echo_Server/Inc/lcd_log_conf.h          LCD Log configuration file
  - LwIP/LwIP_TCP_Echo_Server/Inc/stm32f1xx_hal_conf.h    HAL configuration file
  - LwIP/LwIP_TCP_Echo_Server/Inc/stm32f1xx_it.h          STM32 interrupt handlers header file
  - LwIP/LwIP_TCP_Echo_Server/Inc/main.h                  Main program header file
  - LwIP/LwIP_TCP_Echo_Server/Inc/lwipopts.h              LwIP stack configuration options
  - LwIP/LwIP_TCP_Echo_Server/Inc/tcp_echoserver.h        Header for tcp echoserver application
  - LwIP/LwIP_TCP_Echo_Server/Src/app_ethernet.c          Ethernet specefic module
  - LwIP/LwIP_TCP_Echo_Server/Src/stm32f1xx_it.c          STM32 interrupt handlers
  - LwIP/LwIP_TCP_Echo_Server/Src/main.c                  Main program
  - LwIP/LwIP_TCP_Echo_Server/Src/system_stm32f1xx.c      STM32F1xx system clock configuration file
  - LwIP/LwIP_TCP_Echo_Server/Src/ethernetif.c            Interfacing LwIP to ETH driver
  - LwIP/LwIP_TCP_Echo_Server/Src/tcp_echoserver.c        tcp echoserver application


@par Hardware and Software environment

  - This application runs on STM32F107xC Devices.
    
  - This application has been tested with the following environments:
     - STM3210C-EVAL board   
     - echotool: (http://bansky.net/echotool/) is used as echo client that sends
       data to the server and checking whether they came back      
      
  - STM3210C-EVAL revC Set-up
    - Make sure that the following jumpers: JP3 JP4 JP11 JP12 JP13 JP14 are on the position 2-3
    - Connect the eval board to remote PC (through a crossover ethernet cable)
      or to your local network (through a straight ethernet cable)
  
  - 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
         
 * <h3><center>&copy; COPYRIGHT STMicroelectronics</center></h3>
 */
