/*!
\file readme.txt
\brief description of HASH context switch using DMA example
\version 2021-10-30, V1.0.0, firmware for GD32W51x
*/
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*/
This demo is based on the GD32W515P-EVAL-V1.0 board, it shows how to suspend a lower priority
HASH calculationtask, and give priority to a higher priority task, after the higher priority task completed,
continue to handle the lower priority task.
When power on, task 1 using HASH mode SHA-224 algorithm is processing. Multiple DMA is used to transfer
data from memory to the HAU processor. During the DMA transmission, a flag is used to trigger task 2
insertion(normally it may be triggered by an interruption in user code).
Task 2 is using HASH mode SHA-256 algorithm. Single DMA mode is used to transfer data from memory
to the HAU processor.
In this example, the message of task 1 to hash is 3567-bit data, the message of task 2 to hash
is 261-bit 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.
