/*!
    \file    readme.txt
    \brief   description of DMA reload transfer number by EXTI interrupt in discontinuous mode

    \version 2025-01-01, V2.5.0, firmware for GD32F3x0
*/

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*/

  This example is based on the GD32350R-EVAL-V1.0 board, it provides a description of 
how to reconfigure the DMA transfer number in discontinuous mode, when use DMA channel1 
to transfer data from RAM memory to USART0 transmit data register, and JP13 on 
GD32350R-EVAL-V1.0 board must be fitted.

  The start of transfer is triggered by software. If the DMA transfer operation is finished 
correctly, data stored array welcome[] will be transfered to a serial port tool by USART0 
and LED1 light up. When the Tamper key is pressed, the DMA transfer number is reconfigured 
and DMA transmission is restarted, then the LED1 toggled.
