wenkong_junshi/Examples/RTC/Calendar_demo/readme.txt

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

    \version 2017-02-10, V1.0.0, firmware for GD32F30x
    \version 2018-10-10, V1.1.0, firmware for GD32F30x
    \version 2018-12-25, V2.0.0, firmware for GD32F30x
    \version 2020-09-30, V2.1.0, firmware for GD32F30x
*/

/*
    Copyright (c) 2020, GigaDevice Semiconductor Inc.

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are permitted provided that the following conditions are met:

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*/

    This demo is based on the GD32307C-EVAL-V1.1 board, it explains 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 the value is correct, by the HyperTerminal set time,the calendar will 
be displayed on the HyperTerminal. 
    The RTC module is in the Backup Domain, and is not reset by the system reset.