/**
  @page PWR_Standby PWR_STANDBY example
  
  @verbatim
  ******************** (C) COPYRIGHT 2014 STMicroelectronics *******************
  * @file    PWR/PWR_Standby/readme.txt
  * @author  MCD Application Team
  * @version V1.0.0
  * @date    18-June-2014
  * @brief   Description of the PWR STANDBY 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

This example shows how to enter the system to STANDBY mode and wake-up from this
mode using Wake up Pin 1 (PA.0).
This example shows also how to configure the STM32L0xx system to measure 
STANDBY mode current consumption.

In the associated software, the system clock is set to 2 MHz, the SysTick is 
programmed to generate an interrupt each 1 ms.

In the associated software
  - the system clock is set to 2 MHz
  - Wake Up Pin 1 is configured to wake up the system after entering Standby mode
  - the SysTick is programmed to generate an interrupt each 1 ms.
  
The system enters STANDBY mode after 5s and will wait for pressing wake up Pin.
Current consumption could be monitored through an ampermeter.

The above scenario is repeated in an infinite loop.
 - LED3 ON: HAL configuration failed (system will go to an infinite loop)


    - STANDBY Mode 
    ===============
            - VREFINT OFF with fast wakeup enabled
            - No IWDG
            - Wakeup using WakeUp Pin 1 (PA.0)


@note This example can not be used in DEBUG mode, this is due to the fact 
      that the Cortex-M0+ core is no longer clocked during low power mode 
      so debugging features are disbaled

@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 need to ensure that the SysTick time base is always set to 1 millisecond
      to have correct HAL operation.

@par Directory contents  

  - PWR/PWR_STANDBY/Inc/stm32l0xx_conf.h     Library Configuration file
  - PWR/PWR_STANDBY/Inc/stm32l0xx_it.h       Header for stm32l0xx_it.c
  - PWR/PWR_STANDBY/Inc/main.h               header file for main.c
  - PWR/PWR_STANDBY/Src/system_stm32l0xx.c   STM32L0xx system clock configuration file
  - PWR/PWR_STANDBY/Src/stm32l0xx_it.c       Interrupt handlers
  - PWR/PWR_STANDBY/Src/main.c               Main program
  - PWR/PWR_STANDBY/Src/stm32l0xx_hal_msp.c  HAL MSP module

@par Hardware and Software environment

  - This example runs on STM32L051xx, STM32L052xx, STM32L053xx STM32L062xx and 
    STM32L063xx device lines RevZ
    
  - This example has been tested with STM32L0538-DISCO RevB  board and can be
    easily tailored to any other supported device and development board.

  - STM32L0538-DISCO Set-up
    - Use LED3 connected PB.04 pin
    - Use the User Button B1 connected to PA.0 to wake up from standby mode.
    - Disconnect the JP4, then measure the IDD current between the JP4 position 1-2

@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>
 */
