/**
  @page ADC_RegularConversion_DMA conversion using DMA for Data transfer

  @verbatim
  ******************** (C) COPYRIGHT 2017 STMicroelectronics *******************
  * @file    ADC/ADC_RegularConversion_DMA/readme.txt 
  * @author  MCD Application Team
  * @brief   Description of the ADC RegularConversion DMA example.
  ******************************************************************************
  * @attention
  *
  * Copyright (c) 2017 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 Example Description 

How to use the ADC3 and DMA to transfer continuously converted data from 
ADC3 to memory.

The ADC3 is configured to convert continuously ADC_CHANNEL_4.

Each time an end of conversion occurs the DMA transfers, in circular mode, the
converted data from ADC3 DR register to the uhADCxConvertedValue variable.

In this example, the system clock is 180MHz, APB2 = 90MHz and ADC clock = APB2/4. 
Since ADC3 clock is 22.5 MHz and sampling time is set to 3 cycles, the conversion 
time to 12bit data is 12 cycles so the total conversion time is (12+3)/22.5= 0.67us(6Msps).

User can vary the ADC_CHANNEL_4 voltage using the Eval Board potentiometer (P2) connected to PA.4.
SB94 must be closed to use the potentiometer.

STM32 Eval boards LEDs can be used to monitor the transfer status:
  - LED1 is ON when the conversion is complete.
  - LED3 is ON when there are an error in initialization.

@par Keywords

Analog, ADC, Analog to Digital Converter, Regular Conversion, DMA, Continuous Conversion

@par Directory contents 

  - ADC/ADC_RegularConversion_DMA/Inc/stm32f4xx_hal_conf.h    HAL configuration file
  - ADC/ADC_RegularConversion_DMA/Inc/stm32f4xx_it.h          DMA interrupt handlers header file
  - ADC/ADC_RegularConversion_DMA/Inc/main.h                  Header for main.c module  
  - ADC/ADC_RegularConversion_DMA/Src/stm32f4xx_it.c          DMA interrupt handlers
  - ADC/ADC_RegularConversion_DMA/Src/main.c                  Main program
  - ADC/ADC_RegularConversion_DMA/Src/stm32f4xx_hal_msp.c     HAL MSP file 
  - ADC/ADC_RegularConversion_DMA/Src/system_stm32f4xx.c      STM32F4xx system source file

@par Hardware and Software environment 

  - This example runs on STM32F446xx devices.
  
  - This example has been tested with STM32446E-EVAL board revB 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 example


 */
