wenkong_junshi/Examples/DMA/Flash_to_ram/readme.txt

/*!
    \file    readme.txt
    \brief   description of the DMA flash to ram example

    \version 2017-02-10, V1.0.0, firmware for GD32F30x
    \version 2018-10-10, V1.1.0, firmware for GD32F30x
    \version 2018-12-25, V2.0.0, firmware for GD32F30x
    \version 2020-09-30, V2.1.0, firmware for GD32F30x
*/

/*
    Copyright (c) 2020, GigaDevice Semiconductor Inc.

    Redistribution and use in source and binary forms, with or without modification, 
are permitted provided that the following conditions are met:

    1. Redistributions of source code must retain the above copyright notice, this 
       list of conditions and the following disclaimer.
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       this list of conditions and the following disclaimer in the documentation 
       and/or other materials provided with the distribution.
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       may be used to endorse or promote products derived from this software without 
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    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 
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*/


  This example is based on the GD32307C-EVAL-V1.1 board, it provides a description of how to 
use DMA channel0 to transfer data buffer from FLASH memory to embedded SRAM memory.
    
  Before programming the flash addresses, an erase operation is performed firstly.
After the erase operation, a comparison between FLASH memory and 0xFFFFFFFF(Reset value) 
is done to check that the FLASH memory has been correctly erased.

  Once the erase operation is finished correctly, the programming operation will be
performed by using the fmc_programword function. The written data is transfered to 
embedded SRAM memory by DMA0 Channel0. The transfer is started by enabling the DMA0 Channel0.
At the end of the transfer, a Transfer Complete interrupt is generated since it
is enabled. A comparison between the FLASH memory and embedded SRAM memory is done to
check that all data have been correctly transferred.If the result of comparison is passed,
LED2 to LED5 light up. Otherwise LED2 and LED4 light up.