/*!
    \file    readme.txt
    \brief   description of SHA224_SHA256_dma example

    \version 2026-02-06, V3.0.0, firmware for GD32F20x
*/

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*/

  This demo is based on the GD32207i-EVAL-V1.2 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 2040-bit 
(256 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.
  JP5 must be jumpped to USART.
   All result data can be displayed on the PC HyperTerminal using the USART, and the 
expected print results are as follows:

message to be hashed:

The GD32 F2 series is the result of a perfect symbiosis of the real-time control capabilities of an MCU and the signal processing performance of a DSP, and thus complements the GD32 portfolio with a new class of devices, digital signal controllers (DSC).  

SHA224 message digest (224 bits):

0x94d85610    
0xccfa9b1b    
0x729c97bc    
0x1008b5dd    
0x519ebfe6    
0x8dad80b2    
0xa3fce4f3    
  

SHA256 message digest (256 bits):

0x3a78ae01    
0xe2ea5317    
0xd4557586    
0x61302ee4    
0xbdcb9417    
0x64f6707a    
0x7064f10f    
0xbdab2f2    

  
