71 lines
2.9 KiB
Plaintext
71 lines
2.9 KiB
Plaintext
/**
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@page CRC_CalculateAndCheck CRC : CRC calculation and computed CRC value checking
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@verbatim
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******************** (C) COPYRIGHT 2017 STMicroelectronics *******************
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* @file Examples_LL/CRC/CRC_CalculateAndCheck/readme.txt
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* @author MCD Application Team
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* @brief Description of the CRC_CalculateAndCheck example.
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******************************************************************************
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* @attention
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*
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* Copyright (c) 2017 STMicroelectronics.
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* All rights reserved.
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*
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* This software is licensed under terms that can be found in the LICENSE file
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* in the root directory of this software component.
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* If no LICENSE file comes with this software, it is provided AS-IS.
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*
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******************************************************************************
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@endverbatim
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@par Example Description
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This example shows how to configure CRC calculation unit to get a CRC code of a given data buffer,
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based on a fixed generator polynomial (default value 0x4C11DB7). Peripheral initialization done
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using LL unitary services functions for optimization purpose (performance and size).
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CRC Peripheral is configured to work with default polynomial value (32-bit long).
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Normal representation of this polynomial value is :
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X^32 + X^26 + X^23 + X^22 + X^16 + X^12 + X^11 + X^10 +X^8 + X^7 + X^5 + X^4 + X^2 + X + 1.
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Generated CRC value is then 32 bits long.
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Example execution:
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After startup from reset and system configuration, CRC configuration is performed.
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CRC code of a given data buffer is computed.
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Data buffer length has been chosen as an exact nb of u32 (32-bit words).
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Once calculated, CRC value (uwCRCValue) is compared to the CRC expected value (uwExpectedCRCValue),
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and if both are equal, LED2 is turned On.
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In case of errors, LED2 is blinking (1sec period).
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@par Keywords
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Security, CRC, CRC Polynomial, IEC 60870-5, hardware CRC, user-defined, generating polynomial, CRC Calculate
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@par Directory contents
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- CRC/CRC_CalculateAndCheck/Inc/stm32f4xx_it.h Interrupt handlers header file
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- CRC/CRC_CalculateAndCheck/Inc/main.h Header for main.c module
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- CRC/CRC_CalculateAndCheck/Inc/stm32_assert.h Template file to include assert_failed function
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- CRC/CRC_CalculateAndCheck/Src/stm32f4xx_it.c Interrupt handlers
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- CRC/CRC_CalculateAndCheck/Src/main.c Main program
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- CRC/CRC_CalculateAndCheck/Src/system_stm32f4xx.c STM32F4xx system source file
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@par Hardware and Software environment
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- This example runs on STM32F411xx devices.
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- This example has been tested with NUCLEO-F411RE board and can be
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easily tailored to any other supported device 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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*/
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