/**
  @page USART_HalfDuplex USART Half Duplex example
  
  @verbatim
  ******************** (C) COPYRIGHT 2011 STMicroelectronics *******************
  * @file    USART/HalfDuplex/readme.txt 
  * @author  MCD Application Team
  * @version V3.5.0
  * @date    08-April-2011
  * @brief   Description of the USART Half Duplex example.
  ******************************************************************************
  * THE PRESENT FIRMWARE WHICH IS FOR GUIDANCE ONLY AIMS AT PROVIDING CUSTOMERS
  * WITH CODING INFORMATION REGARDING THEIR PRODUCTS IN ORDER FOR THEM TO SAVE
  * TIME. AS A RESULT, STMICROELECTRONICS SHALL NOT BE HELD LIABLE FOR ANY
  * DIRECT, INDIRECT OR CONSEQUENTIAL DAMAGES WITH RESPECT TO ANY CLAIMS ARISING
  * FROM THE CONTENT OF SUCH FIRMWARE AND/OR THE USE MADE BY CUSTOMERS OF THE
  * CODING INFORMATION CONTAINED HEREIN IN CONNECTION WITH THEIR PRODUCTS.
  ******************************************************************************
   @endverbatim

@par Example Description 

This example provides a basic communication between USARTy and USARTz in 
Half-Duplex mode using flags. USARTy and USARTz can be USART1 and USART2 or
USART2 and USART3, depending on the STMicroelectronics EVAL board you are using.

First, the USARTy sends data from TxBuffer1 buffer to USARTz using TXE flag.
Data received using RXNE flag by USARTz is stored in RxBuffer2 then compared with
the sent ones and the result of this comparison is stored in the "TransferStatus1" 
variable.
 
Then, the USARTz sends data from TxBuffer2 buffer to USARTy using TXE flag.
Data received using RXNE flag by USARTy is stored in RxBuffer1 then compared with
the sent ones and the result of this comparison is stored in the "TransferStatus2" 
variable.     

USARTy and USARTz configured as follow:
  - BaudRate = 230400 baud  
  - Word Length = 8 Bits
  - One Stop Bit
  - Even parity
  - Hardware flow control disabled (RTS and CTS signals)
  - Receive and transmit enabled

@par Directory contents 

  - USART/HalfDuplex/platform_config.h    Evaluation board specific configuration file
  - USART/HalfDuplex/stm32f10x_conf.h     Library Configuration file
  - USART/HalfDuplex/stm32f10x_it.h       Interrupt handlers header file
  - USART/HalfDuplex/stm32f10x_it.c       Interrupt handlers
  - USART/HalfDuplex/main.c               Main program
  - USART/HalfDuplex/system_stm32f10x.c   STM32F10x system source file
  
@par Hardware and Software environment 

  - This example runs on STM32F10x Connectivity line, High-Density, High-Density 
    Value line, Medium-Density, XL-Density, Medium-Density Value line, Low-Density 
    and Low-Density Value line Devices.
  
  - This example has been tested with STMicroelectronics STM32100E-EVAL (High-Density
    Value line), STM32100B-EVAL (Medium-Density Value line), STM3210C-EVAL (Connectivity line), 
    STM3210E-EVAL (High-Density and XL-Density) and STM3210B-EVAL (Medium-Density) 
    evaluation boards and can be easily tailored to any other supported device 
    and development board.
    To select the STMicroelectronics evaluation board used to run the example, 
    uncomment the corresponding line in USART/HalfDuplex/platform_config.h file

  - STM32100E-EVAL Set-up 
    - Connect USART1_Tx(PA.09) to USART2_Tx(PA.02).
      
  - STM32100B-EVAL Set-up   
    - Connect USART1_Tx(PA.09) to USART2_Tx(PD.05).
 
  - STM3210C-EVAL Set-up 
    - Connect USART2 Tx pin (PD.05) to USART3 Tx pin (PC.10) and connect a 
      pull-up resistor to this line (10K).  
      @note In this case USART3 Tx pin is remapped by software.
            Make sure that jumpers JP19 and JP18 are open.
            
  - STM3210E-EVAL Set-up 
    - Connect USART1_Tx(PA.09) to USART2_Tx(PA.02) and connect a pull-up resistor to 
      this line (10K).  

  - STM3210B-EVAL Set-up   
    - Connect USART1_Tx(PA.09) to USART2_Tx(PD.05) and connect a pull-up resistor to 
      this line (10K). 
  
@par How to use it ? 

In order to make the program work, you must do the following :
 - Copy all source files from this example folder to the template folder under
   Project\STM32F10x_StdPeriph_Template
 - Open your preferred toolchain 
 - Rebuild all files and load your image into target memory
 - Run the example 

@note
 - Low-density Value line devices are STM32F100xx microcontrollers where the 
   Flash memory density ranges between 16 and 32 Kbytes.
 - Low-density devices are STM32F101xx, STM32F102xx and STM32F103xx 
   microcontrollers where the Flash memory density ranges between 16 and 32 Kbytes.
 - Medium-density Value line devices are STM32F100xx microcontrollers where
   the Flash memory density ranges between 64 and 128 Kbytes.  
 - Medium-density devices are STM32F101xx, STM32F102xx and STM32F103xx 
   microcontrollers where the Flash memory density ranges between 64 and 128 Kbytes.
 - High-density Value line devices are STM32F100xx microcontrollers where
   the Flash memory density ranges between 256 and 512 Kbytes.
 - High-density devices are STM32F101xx and STM32F103xx microcontrollers where
   the Flash memory density ranges between 256 and 512 Kbytes.
 - XL-density devices are STM32F101xx and STM32F103xx microcontrollers where
   the Flash memory density ranges between 512 and 1024 Kbytes.
 - Connectivity line devices are STM32F105xx and STM32F107xx microcontrollers.
    
 * <h3><center>&copy; COPYRIGHT 2011 STMicroelectronics</center></h3>
 */