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Example description

  
EXTI_Example EXTI Configuration Example
  
Example Description 

This example shows how to configure external interrupt lines.
In this example, 2 EXTI lines (EXTI Line0 and Line15) are configured  to generate
an interrupt on each rising and falling edge, respectively. 
In the interrupt routine a led connected to a specific GPIO pin is toggled.

In this example:
  - EXTI Line0 is connected to PA0 pin
  - EXTI Line15 is connected to PG15 pin

After EXTI configuration, a software interrupt is generated on the EXTI0 toggles LED1.
After that,
  when falling edge is detected on EXTI Line0, LED1 toggles
  when falling edge is detected on EXTI Line15, LED2 toggles

On STM322xG-EVA,
  EXTI Line0 is connected to Wakeup push-button
  EXTI Line15 is connected to Key push-button

	  In this example, EXTILine15_Config() function can be substituted by 
      STM_EVAL_PBInit(Button_KEY, Mode_EXTI) provided in the STM322xG-EVAL driver.


Directory contents 

  - EXTI/EXTI_Example/stm32f2xx_conf.h    Library Configuration file
  - EXTI/EXTI_Example/stm32f2xx_it.h      Interrupt handlers header file
  - EXTI/EXTI_Example/stm32f2xx_it.c       Interrupt handlers
  - EXTI/EXTI_Example/main.c              Main program
  - EXTI/EXTI_Example/system_stm32f2xx.c  STM32F2xx system source file

      The "system_stm32f2xx.c" is generated by an automatic clock configuration 
      tool and can be easily customized to your own configuration. 
      To select different clock setup, use the "STM32F2xx_Clock_Configuration_V1.0.0.xls" tool.


Hardware and Software environment

  - This example runs on STM32F2xx Devices.

  - This example has been tested with STM322xG-EVAL RevB and can be easily tailored
    to any other development board

  - STM322xG-EVAL Set-up  
    - Use LED1 and LED2 connected respectively to PG.06 and PG.08
    - Use the Key push-button connected to pin PG15 (EXTI Line15)
    - Use the Wakeup push-button connected to pin PA0 (EXTI Line0)