/*!
    \file    readme.txt
    \brief   description of EXTI Key Interrupt example

    \version 2026-02-12, V2.0.3, demo for GD32A490
*/

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*/

  This example is based on the GD32A490Z-START-V1.0 board, it provides a method
to use the key for controlling the LED by the interrupt. The user can toggle the
output state of LED2 by pressing the User Key.

  On the GD32A490Z-START-V1.0 board, the User Key connectes to PA0 and
the LED2 connects to PE5.
