/*!
    \file    readme.txt
    \brief   description of the FWDGT_key example
    
    \version 2025-08-08, V2.4.0, firmware for GD32E23x
*/

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*/

  This example is based on the GD32E230C-EVAL-V1.1 board, it shows how to reload the 
FWDGT counter at regulate period using the EXTI interrupt. The FWDGT timeout 
is set to 1.6s (the timeout may varies due to IRC40K frequency dispersion).
 
  An EXTI is connected to a specific GPIO pin and configured to generate an interrupt
on its falling edge: when the EXTI Line interrupt is triggered (by pressing the Tamper
Key on the board), the corresponding interrupt is served. In the ISR, FWDGT 
counter is reloaded). As a result, when the FWDGT counter is reloaded, which prevents 
any FWDGT reset, LED3 remain illuminated.
  
  If the EXTI Line interrupt does not occur, the FWDGT counter is not reloaded before
the FWDGT counter reaches 00h, and the FWDGT reset. If the FWDGT reset is generated, 
LED2 turned on and LED3 turned off with the system reset. FWDGTRST flag is set by hardware,
and then LED3 is turned on.
