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/**
@page DMA_FLASHToRAM DMA example
@verbatim
******************************************************************************
* @file Examples_MIX/DMA/DMA_FLASHToRAM/readme.txt
* @author MCD Application Team
* @brief Description of the DMA example.
******************************************************************************
*
* Copyright (c) 2019 STMicroelectronics. All rights reserved.
*
* This software component is licensed by ST under BSD 3-Clause license,
* the "License"; You may not use this file except in compliance with the
* License. You may obtain a copy of the License at:
* opensource.org/licenses/BSD-3-Clause
*
******************************************************************************
@endverbatim
@par Example Description
How to use a DMA to transfer a word data buffer from Flash memory to embedded
SRAM through the STM32WBxx DMA HAL and LL API. The LL API is used for
performance improvement.
At the beginning of the main program the HAL_Init() function is called to reset
all the peripherals, initialize the Flash interface and the systick.
Then the SystemClock_Config() function is used to configure the system
clock (SYSCLK) to run at 64 MHz.
DMA1_Channel1 is configured to transfer the contents of a 32-word data
buffer stored in Flash memory to the reception buffer declared in RAM.
The start of transfer is triggered by LL API. DMA1_Channel1 memory-to-memory
transfer is enabled. Source and destination addresses incrementing is also enabled.
The transfer is started by setting the channel enable bit for DMA1_Channel1.
At the end of the transfer a Transfer Complete interrupt is generated since it
is enabled and the callback function (customized by user) is called.
Board's LEDs can be used to monitor the transfer status:
- LED2 is ON when the transfer is complete (into the Transfer Complete interrupt
routine).
- LED1 is ON when there is a transfer error
- LED3 is ON when a Error_Handler is called
It is possible to select a different channel for the DMA transfer
example by modifying defines values in the file main.h.
@note Care must be taken when using HAL_Delay(), this function provides accurate delay (in milliseconds)
based on variable incremented in SysTick ISR. This implies that if HAL_Delay() is called from
a peripheral ISR process, then the SysTick interrupt must have higher priority (numerically lower)
than the peripheral interrupt. Otherwise the caller ISR process will be blocked.
To change the SysTick interrupt priority you have to use HAL_NVIC_SetPriority() function.
@note This example need to ensure that the SysTick time base is always set to 1 millisecond
to have correct HAL operation.
@par Keywords
System, DMA, Data Transfer, Memory to memory, Flash, SRAM
@par Directory contents
- DMA/DMA_FLASHToRAM/Src/system_stm32wbxx.c STM32WBxx system clock configuration file
- DMA/DMA_FLASHToRAM/Src/stm32wbxx_it.c Interrupt handlers
- DMA/DMA_FLASHToRAM/Src/main.c Main program
- DMA/DMA_FLASHToRAM/Src/stm32wbxx_hal_msp.c HAL MSP module
- DMA/DMA_FLASHToRAM/Inc/stm32wbxx_hal_conf.h HAL Configuration file
- DMA/DMA_FLASHToRAM/Inc/stm32wbxx_it.h Interrupt handlers header file
- DMA/DMA_FLASHToRAM/Inc/main.h Main program header file
@par Hardware and Software environment
- This example runs on STM32WB15CCUx Devices.
- This example has been tested with STMicroelectronics NUCLEO-WB15CC
board and can be easily tailored to any other supported device
and development board.
@par How to use it ?
In order to make the program work, you must do the following :
- Open your preferred toolchain
- Rebuild all files and load your image into target memory
- Run the example
* <h3><center>© COPYRIGHT STMicroelectronics</center></h3>
*/
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