/**
  @page PWR_PVD PWR Programmable Voltage Detector (PVD) example
  
  @verbatim
  ******************** (C) COPYRIGHT 2012 STMicroelectronics *******************
  * @file    PWR/PVD/readme.txt 
  * @author  MCD Application Team
  * @version V1.1.1
  * @date    13-April-2012
  * @brief   Description of the PWR Programmable Voltage Detector (PVD) example.
  ******************************************************************************
  *
  * Licensed under MCD-ST Liberty SW License Agreement V2, (the "License");
  * You may not use this file except in compliance with the License.
  * You may obtain a copy of the License at:
  *
  *        http://www.st.com/software_license_agreement_liberty_v2
  *
  * Unless required by applicable law or agreed to in writing, software 
  * distributed under the License is distributed on an "AS IS" BASIS, 
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  *
  ******************************************************************************
   @endverbatim

@par Example Description 

This example shows how to configure the programmable voltage detector using
an external interrupt line. In this example, EXTI line 16 is configured to generate 
an interrupt on each rising or falling edge of the PVD output signal (which 
indicates that the Vdd voltage is below the PVD threshold).
In the interrupt routine a led connected to a specific GPIO pin is toggled every 
time the voltage drops below or above the target threshold.

A LED connected to a specific GPIO pin is toggling to indicate that the system 
is in RUN.

@par Directory contents 

  - PWR/PVD/stm32l1xx_conf.h    Library Configuration file
  - PWR/PVD/stm32l1xx_it.c      Interrupt handlers
  - PWR/PVD/stm32l1xx_it.h      Interrupt handlers header file
  - PWR/PVD/main.c              Main program
  - PWR/PVD/system_stm32l1xx.c  STM32L1xx system source file
  
@note The "system_stm32l1xx.c" is generated by an automatic clock configuration 
      system and can be easily customized to your own configuration. 
      To select different clock setup, use the "STM32L1xx_Clock_Configuration_V1.1.0.xls" 
      provided with the AN3309 package available on <a href="http://www.st.com/internet/mcu/family/141.jsp">  ST Microcontrollers </a>
         
@par Hardware and Software environment

  - This example runs on STM32L1xx Ultra Low Power High-, Medium-Density and Medium-Density Plus Devices.
  
  - This example has been tested with STMicroelectronics STM32L152D-EVAL (STM32L1xx 
    Ultra Low Power High-Density) and STM32L152-EVAL (STM32L1xx Ultra Low 
    Power Medium-Density) evaluation board and can be easily tailored to any 
    other supported device and development board.

  - STM32L152-EVAL Set-up
    - Use LED1 led connected to PD.00 pin
    - Use LED2 led connected to PD.01 pin    
    - Use VDD Adjust (RV2).
    - Make sure That jumper JP13 in position(1-->2).

  - STM32L152D-EVAL Set-up
    - Use LED1 led connected to PD.03 pin
    - Use LED2 led connected to PD.07 pin    
    - Use VDD Adjust (RV1).
    - Make sure That jumper JP5 in position(1-->2).
      
@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\STM32L1xx_StdPeriph_Templates
 - Open your preferred toolchain 
 - Rebuild all files and load your image into target memory
 - Run the example

@note
- Ultra Low Power Medium-density devices are STM32L151xx and STM32L152xx 
  microcontrollers where the Flash memory density ranges between 64 and 128 Kbytes.
- Ultra Low Power Medium-density Plus devices are STM32L151xx, STM32L152xx and 
  STM32L162xx microcontrollers where the Flash memory density is 256 Kbytes.
- Ultra Low Power High-density devices are STM32L151xx, STM32L152xx and STM32L162xx 
  microcontrollers where the Flash memory density is 384 Kbytes.
    
 * <h3><center>&copy; COPYRIGHT STMicroelectronics</center></h3>
 */


