/*!
    \file  readme.txt
    \brief description of calendar demo

    \version 2025-08-20, V3.0.2, demo for GD32F403
*/

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*/
  This demo shows how to configure the RTC module. In this demo, RTC peripheral is 
configured to display calendar.Select LXTAL as RTC clock source. And the HyperTerminal 
should be connected to the evaluation board via COM0.
  After start-up,get key value from BKP data register or bit RTCSRC of backup domain 
control register. If the value is incorrect, the program will ask to set the time on the 
HyperTerminal.If thekey value is correct, by the HyperTerminal set time,the calendar will 
be displayedon the HyperTerminal.  
  The RTC module is in the Backup Domain, and is not reset by the system reset.
 