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

    \version 2025-08-09, V1.7.0, firmware for GD32A50x
*/

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*/
  
  This example is based on the GD32A503V-EVAL-V1.1 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 perpheral 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 transfering to DMA controller.
  The steps are shown as follows:
  1. At the start, users need to press TAMPER to generate a DMA request.
  2. Then, users press the Wakeup key to generate a synchronization event to connect the DMA request
     to the DMAMUX multiplexer channel output, to start DMA requests transfering, the first DMA 
     request will be transferred.
  3. Then press the TAMPER key 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 transfered, 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.
