/**
  @page ADC_AnalogWatchdog ADC example
  
  @verbatim
  ******************** (C) COPYRIGHT 2016 STMicroelectronics *******************
  * @file    Examples_LL/ADC/ADC_AnalogWatchdog/readme.txt 
  * @author  MCD Application Team
  * @version V1.0.0
  * @date    14-April-2017
  * @brief   Description of the ADC_AnalogWatchdog example.
  ******************************************************************************
  *
  * Redistribution and use in source and binary forms, with or without modification,
  * are permitted provided that the following conditions are met:
  *   1. Redistributions 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 its contributors
  *      may be used to endorse or promote products derived from this software
  *      without specific prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER 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 Example Description

How to use an ADC peripheral with an ADC analog watchdog to monitor a channel 
and detect when the corresponding conversion data is outside the window 
thresholds.
This example is based on the STM32F1xx ADC LL API.
The peripheral initialization is done using LL unitary service functions
for optimization purposes (performance and size).

Example configuration:
ADC is configured to convert a single channel, in continuous conversion mode,
from SW trigger.
Analog watchdog is configured to monitor all channels on group regular
(therefore, including the selected channel), 
low threshold is set to 0V and high threshold is set to Vdda/2.
ADC interruption enabled: Analog watchdog 1.

Example execution:
From the main program execution, the ADC converts the selected channel continuously.
When conversion data is out of analog watchdog window, ADC interruption occurs.
Into analog watchdog callback function, a status variable is set
and a LED2 is turned-on (LED2 turns ON into Analog Watchdog window).
At each press on User Button, the ADC analog watchdog is rearmed to be ready
for another trig.

LED2 is blinking every 1 sec in case of error.

Note: In case of noise on voltage applied on ADC channel input, ADC analog watchdog
      may trig at a voltage level with an uncertainty of tens of mV.

For debug: variables to monitor with debugger watch window:
 - "ubAnalogWatchdog1Status": analog watchdog state

Connection needed: use an external power supply, adjust supply voltage and connect 
it to analog input pin (cf pin below).

Other peripherals used:
  1 GPIO for User Button
  1 GPIO for LED2
  1 GPIO for analog input: PA.04 (Arduino connector CN8 pin A2, Morpho connector CN7 pin 32)

@par Directory contents 

  - ADC/ADC_AnalogWatchdog/Inc/stm32f1xx_it.h          Interrupt handlers header file
  - ADC/ADC_AnalogWatchdog/Inc/main.h                  Header for main.c module
  - ADC/ADC_AnalogWatchdog/Inc/stm32_assert.h          Template file to include assert_failed function
  - ADC/ADC_AnalogWatchdog/Src/stm32f1xx_it.c          Interrupt handlers
  - ADC/ADC_AnalogWatchdog/Src/main.c                  Main program
  - ADC/ADC_AnalogWatchdog/Src/system_stm32f1xx.c      STM32F1xx system source file


@par Hardware and Software environment

  - This example runs on STM32F103xB devices.
    
  - This example has been tested with STM32F103RB-Nucleo board 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

 * <h3><center>&copy; COPYRIGHT STMicroelectronics</center></h3>
 */
