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

    \version 2026-02-04, V1.6.0, firmware for GD32VW55x
*/

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*/

  This demo is based on the GD32VW553H-EVAL-V1.2 board, it explains how
to use the auto wakeup function of RTC. In this demo, RTC peripheral is configured to keep
time and generate the wakeup interrupt.

  The RTC clock source can be choose to LXTAL or IRC32K by uncommented the corresponding
define in main file. And the HyperTerminal should be connected to the evaluation
board via USART.

  After start-up, the program checks if the BKP data register is written to a key
value. If the value is not correct, the program will ask to set the time value on the
HyperTerminal. If the key value is correct, the current time and subsecond value
will be displayed on the HyperTerminal.

  Then LED1 is turned on.

   Auto wakeup interrupt will be generated every  6 seconds , the current time
will be print on the HyperTerminal, and LED1 toggles.