/*!
    \file    readme.txt
    \brief   description of the FWDGT_key example

    \version 2025-08-01, V1.0.0, firmware for gd32c2x1
*/

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*/

  This example is based on the GD32C231C-EVAL-V1.0 board, it shows
how to reload the FWDGT counter at regulate period using the EXTI interrupt. The FWDGT
timeout is set to 3s (the timeout may varies due to IRC32K 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,  LED1 remains 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.

  There are three operation methods as follow:
  1.After the download is completed and the system is powered on, LED1 flashes once and
then LED2 starts flashing.

  2.After the download is completed and the system is powered on, start to press the wake
button in quick succession, then LED1 is always on, and stop pressing the wake
button in quick succession and LED2 starts to flash.

  3.After the download is completed and the system is powered on, LED1 flashes once and then
LED2 starts flashing. At this time, after pressing the wake button in rapid succession,
LED2 is always on, and after stopping the rapid and continuous pressing of the wake button,
LED2 starts flashing.
