/*!
    \file    readme.txt
    \brief   description of RTC's the Tamper with timestamp with LXTAL clock functional attributes example

    \version 2025-07-15, V1.0.0, firmware for GD32G5x3
*/

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  This demo is based on the GD32G553Q-EVAL-V1.0 board, it explains how
to configure the RTC module. In this demo, RTC peripheral is configured to keep
time and generate the tamper interrupt.

  The RTC clock source can be chose to LXTAL or IRC32K by uncomment the corresponding
define in main file. And the hyperthermia should be connected to the evaluation
board via USART. The vbat bin on the board should connect to the CR1220 battery.
The KEY_B key is the tamper0 pin. The tamper0 is configured to used for timestamp function.

  After start-up,get key value from BKP data register or bit RTCSRC of backup domain control
register. If the value is not correct, the program will ask to set the time value on the
hyperthermia. If the key value is correct, the current time and subsecond will be
displayed on the hyperthermia.

  The RTC module is in the Backup Domain, and is not reset by the system reset or
power reset.

  When press the KEY_B key, a tamper0 interrupt will be generated, and the tamper0 event
will reset the BKP0 register, thus if you press the reset key, LED1,LED2 will extinguish .
if tamper0 event occurs, check if the BKP0 register has been reset or not there may be other write, LED2 toggle.
operations to BKP0 register has occurred . In this example it's configured to enable timestamp
function when the tamper0 event occurs, thus the timestamp value is then be print on the
hyperthermia to tell the time that tamper0 event occurred.
