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

    \version 2026-02-04, V1.3.0, firmware for GD32H75E
*/

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  This example is based on the GD32H75EY-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 memory to peripheral. 
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 transferring 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 transferring, the first DMA 
     request will be transferred.
  3. Then press the TAMPER key for another 3 times to generate the rest 3 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, LED3 will be on, otherwise, LED4 will be on.
