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/**
@page CRC_CalculateAndCheck CRC : CRC calculation and computed CRC value checking
@verbatim
******************************************************************************
* @file Examples_LL/CRC/CRC_CalculateAndCheck/readme.txt
* @author MCD Application Team
* @brief Description of the CRC_CalculateAndCheck example.
******************************************************************************
*
* Copyright (c) 2019-2021 STMicroelectronics.
* All rights reserved.
*
* This software is licensed under terms that can be found in the LICENSE file
* in the root directory of this software component.
* If no LICENSE file comes with this software, it is provided AS-IS.
*
******************************************************************************
@endverbatim
@par Example Description
How to configure the CRC calculation unit to compute a CRC code for a given data
buffer, based on a fixed generator polynomial (default value 0x4C11DB7). The
peripheral initialization is done using LL unitary service functions for
optimization purposes (performance and size).
The CRC peripheral is configured to work with default polynomial value (32-bit long).
Normal representation of this polynomial value is :
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.
Generated CRC value is then 32 bits long.
Example execution:
After startup from reset and system configuration, CRC configuration is performed (use of default Polynomial and initialisation values).
CRC code of a given data buffer is computed.
Data buffer length has been chosen as not an exact nb of u32 (32-bit words), in order to illustrate
use of offered API for feeding the calculator (u32, u16 or u8 inputs).
The calculated CRC code is stored in uwCRCValue variable.
Once calculated, CRC value (uwCRCValue) is compared to the CRC expected value (uwExpectedCRCValue),
and if both are equal, LED2 is turned On.
In case of errors, LED2 is blinking (1sec period).
@par Keywords
Security, CRC, CRC Polynomial, IEC 60870-5, hardware CRC, user-defined, generating polynomial, CRC Calculate
@par Directory contents
- CRC/CRC_CalculateAndCheck/Inc/stm32wbxx_it.h Interrupt handlers header file
- CRC/CRC_CalculateAndCheck/Inc/main.h Header for main.c module
- CRC/CRC_CalculateAndCheck/Inc/stm32_assert.h Template file to include assert_failed function
- CRC/CRC_CalculateAndCheck/Src/stm32wbxx_it.c Interrupt handlers
- CRC/CRC_CalculateAndCheck/Src/main.c Main program
- CRC/CRC_CalculateAndCheck/Src/system_stm32wbxx.c STM32WBxx system source file
@par Hardware and Software environment
- This example runs on STM32WB55xx devices.
- This example has been tested with P-NUCLEO-WB55 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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