/*!
    \file    readme.txt
    \brief   description of Hash_SHA224_SHA256_dma example

    \version 2021-10-30, V1.0.0, firmware for GD32W51x
*/

/*
    Copyright (c) 2021, GigaDevice Semiconductor Inc.

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*/

  This demo is based on the GD32W515P-EVAL-V1.0 board, it shows how to use the HAU
peripheral to hash data using SHA-224 and SHA-256 algorithms.
  For this example, DMA is used to transfer data from memory to the HAU processor.
The message to hash must be multiple of 512-bit (64 bytes) so the message must be 
padded to multiple of 64 bytes. In this example, the message to hash is 248-bit 
(31 bytes) data.
  The SHA-224 message digest result is a 224-bit data (28 bytes = 7 words) available
in DO0...DO6 registers.
  The SHA-256 message digest result is a 256-bit data (32 bytes = 8 words) available
in DO0...DO7 registers.
  The all result data can be displayed on a PC HyperTerminal using the USART.
