/*!
    \file    readme.txt
    \brief   description of Tamper and waveform detection demo

    \version 2025-08-11, V2.9.0, demo for GD32F20x
*/

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  This demo is based on the GD32207i-EVAL-V1.2 board, it shows how to write/read data 
to/from backup data registers and demonstrates the tamper and waveform detection function. 

  If the TAMPER0_DETECT macro is defined, after system start-up, it writes the data to 
all backup data registers, then check whether the data were correctly written. If yes, 
LED1 is on, otherwise LED2 is on.When the Tamper key(TAMPER0 pin) is pressed, the backup 
data registers are reset and the tamper0 interrupt is generated. In the corresponding 
ISR, it checks whether the backup data registers are cleared or not. If yes, LED3 is 
on, otherwise LED4 is on.
  If the WAVEFORM_DETECT macro is defined and short PI8 and PC13, the program will write 
the data to all backup data registers, then check whether the data were correctly written. 
If yes, LED1 is on, otherwise LED2 is on. At this time, LED3 and LED4 are off, which means 
that waveform receiving and checking is right, tamper1 interrupt is not happened.If PI8 and 
PC13 are disconnected, LED3 will light up, this means that waveform receiving and checking 
is wrong, tamper1 interrupt is happened.

  Tamper and waveform detection only one can be used at the same time.
