/*!
    \file    readme.txt
    \brief   description of GPIO KeyBoard Polling mode example
    
    \version 2025-08-18, V2.5.0, demo for GD32E23x
*/

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*/

  This example is based on the GD32E230V-START-V1.0 board, it provides a description
of GPIO key demo. It uses Mini USB interface to supply power. User button key, LED and 
GD-Link are also included.
  
  After system start-up, firstly, LED1 is flashed once for test and LED1 is on. The user 
can toggle the output state of LED1 by pressing the User key.

  On the GD32E230V-START board, LED1 is connected to PA1. User key is connected to PA0.
