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https://github.com/STMicroelectronics/STM32CubeF1.git
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83 lines
3.7 KiB
Plaintext
83 lines
3.7 KiB
Plaintext
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/**
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@page CRC_Example Cyclic Redundancy Check Example
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@verbatim
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******************** (C) COPYRIGHT 2016 STMicroelectronics *******************
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* @file CRC/CRC_Example/readme.txt
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* @author MCD Application Team
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* @brief Description of Cyclic Redundancy Check Example.
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******************************************************************************
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* @attention
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*
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* <h2><center>© Copyright (c) 2016 STMicroelectronics.
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* All rights reserved.</center></h2>
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*
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* This software component is licensed by ST under BSD 3-Clause license,
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* the "License"; You may not use this file except in compliance with the
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* License. You may obtain a copy of the License at:
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* opensource.org/licenses/BSD-3-Clause
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*
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******************************************************************************
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@endverbatim
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@par Example Description
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How to configure the CRC using the HAL API. The CRC (cyclic
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redundancy check) calculation unit computes the CRC code of a given buffer of
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32-bit data words, using a fixed generator polynomial (0x4C11DB7).
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At the beginning of the main program the HAL_Init() function is called to reset
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all the peripherals, initialize the Flash interface and the systick.
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Then the SystemClock_Config() function is used to configure the system
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clock (SYSCLK) to run at 64 MHz.
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The CRC peripheral configuration is ensured by the HAL_CRC_Init() function.
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This later is calling the HAL_CRC_MspInit()function which core is implementing
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the configuration of the needed CRC resources according to the used hardware (CLOCK,
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GPIO, DMA and NVIC). You may update this function to change CRC configuration.
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The calculated CRC code is compared to displayed on the debugger in uwCRCValue variable.
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Once calculated, the CRC value is compared to the CRC expected value.
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STM32 Eval board's LED can be used to monitor the example status:
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- LED2 is ON when a correct CRC value is calculated
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- LED2 is slowly blinking (1 sec. period) when an uncorrect CRC value is calculated or when there is an initialization error.
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@note Care must be taken when using HAL_Delay(), this function provides accurate delay (in milliseconds)
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based on variable incremented in SysTick ISR. This implies that if HAL_Delay() is called from
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a peripheral ISR process, then the SysTick interrupt must have higher priority (numerically lower)
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than the peripheral interrupt. Otherwise the caller ISR process will be blocked.
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To change the SysTick interrupt priority you have to use HAL_NVIC_SetPriority() function.
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@note The application need to ensure that the SysTick time base is always set to 1 millisecond
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to have correct HAL operation.
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@par Directory contents
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- CRC/CRC_Example/Inc/stm32f1xx_hal_conf.h HAL configuration file
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- CRC/CRC_Example/Inc/stm32f1xx_it.h Interrupt handlers header file
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- CRC/CRC_Example/Inc/main.h Header for main.c module
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- CRC/CRC_Example/Src/stm32f1xx_it.c Interrupt handlers
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- CRC/CRC_Example/Src/main.c Main program
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- CRC/CRC_Example/Src/stm32f1xx_hal_msp.c HAL MSP module
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- CRC/CRC_Example/Src/system_stm32f1xx.c STM32F1xx system source file
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@par Hardware and Software environment
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- This example runs on STM32F103xB devices.
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- This example has been tested with STMicroelectronics STM32F103RB-Nucleo
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evaluation boards and can be easily tailored to any other supported device
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and development board.
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@par How to use it ?
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In order to make the program work, you must do the following:
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- Open your preferred toolchain
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- Rebuild all files and load your image into target memory
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- Run the example
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* <h3><center>© COPYRIGHT STMicroelectronics</center></h3>
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*/
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