/*!
    \file    readme.txt
    \brief   description of DMA request generation example

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

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*/

  This example is based on the GD32G553Q-EVAL-V1.0 board, it provides a description
of how to use DMAMUX request generator channel 0 to generate DMA requests for DMA
transmission.
  In this demo, DMA0 channel 0 is configured to transfer data from peripheral to memory,
without enabling memory to memory mode. DMAMUX request generator channel 0 is configured
to use EXTI_13 line rising edge to generate a DMA request. DMAMUX request multiplexer
channel 0 is configured as synchronization mode, using EXTI_0 line rising edge to start
16 DMA requests transferredto DMA controller.
  The steps are shown as follows:
  1. At the start, users need to press TAMPER key(KEY_B) to generate a DMA request.
  2. Then, users press the Wakeup key(KEY_A) to generate a synchronization event to connect the DMA request
     to the DMAMUX multiplexer channel output, to start DMA requests transferring, the first DMA
     request will be transferred.
  3. Then press the TAMPER key(KEY_B) for another 15 times to generate the rest 15 DMA requests. Every time
     the TAMPER key is pressed, the DMA controller will transfer a data from source address to destination
     address. When all data are transferred, a DMA transfer complete interrupt will occur, and
     the source data array will be compared with the destination data array.
  4. If the transfer is successful, LED1 will be on, otherwise, LED2 will be on.
