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/**
@page CRC_UserDefinedPolynomial CRC : 8-bit CRC calculation using user-defined polynomial value
@verbatim
******************************************************************************
* @file Examples_LL/CRC/CRC_UserDefinedPolynomial/readme.txt
* @author MCD Application Team
* @brief Description of the CRC_UserDefinedPolynomial 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 configure and use the CRC calculation unit to compute an 8-bit CRC code
for a given data buffer, based on a user-defined generating polynomial. The
peripheral initialization is done using LL unitary service functions for
optimization purposes (performance and size).
The CRC peripheral is configured to work with a user defined polynomial value (8-bit long value).
In this example, the polynomial is set manually to 0x9B that is X^8 + X^7 + X^4 + X^3 + X + 1.
Generated CRC value is then 8-bit long.
Example execution:
After startup from reset and system configuration, CRC configuration is performed (use of user-defined Polynomial value).
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 ubCRCValue variable.
Once calculated, CRC value (ubCRCValue) is compared to the CRC expected value (ubExpectedCRCValue),
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
@par Directory contents
- CRC/CRC_UserDefinedPolynomial/Inc/stm32wbxx_it.h Interrupt handlers header file
- CRC/CRC_UserDefinedPolynomial/Inc/main.h Header for main.c module
- CRC/CRC_UserDefinedPolynomial/Inc/stm32_assert.h Template file to include assert_failed function
- CRC/CRC_UserDefinedPolynomial/Src/stm32wbxx_it.c Interrupt handlers
- CRC/CRC_UserDefinedPolynomial/Src/main.c Main program
- CRC/CRC_UserDefinedPolynomial/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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