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

    \version 2021-10-30, V1.0.0, firmware for GD32W51x
*/

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*/

  This demo is based on the GD32W515_EVAL board, it explains how 
to use the timestamp function of RTC. In this demo, RTC peripheral is configured to keep
time and generate the timestamp interrupt.
  
  The RTC clock source can be chose to LXTAL or IRC32K by uncomment the corresponding 
define in main file. And the HyperTerminal should be connected to the evaluation 
board via USART.
  
  After start-up, the program check 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.
  
  The RTC module is in the Backup Domain, and is not reset by the system reset or 
power reset. 
  
  Use dupont cable to connect PC15 and PA2, when press the tamper key, a timestamp
interrupt will be generated, the current time
then be print on the HyperTerminal, and LED1 toggles.