/*!
    \file    readme.txt
    \brief   description of data encrypt/decrypt by using CAU in DMA mode and RTDEC example
    
    \version 2024-01-05, V1.2.0, firmware for GD32H7xx
*/

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*/

  This example is based on the GD32H759I-EVAL-V1.1 board, it shows the how to use
RTDEC to decrypt in real-time when read the ciper data stored in the OSPI flash. That
ciper data is encrypted by CAU in DMA mode. When read ciper data from OSPI flash, the
memory map mode should be enabled.
  After system start-up, firstly, the plain data is encryped by using CAU AES-128 CTR
mode with DMA, then the ciper data is written into the OSPI extern flash.
  Secondly, the RTDEC is configured and the ciper data in OSPI flash is read in memory
map mode. When the cipper data is read, it is decryted by RTDEC.
  Finally, the decrypted data is print into the HyperTerminal, and decrypted data is
compared to the plain data.
