mirror of
https://github.com/STMicroelectronics/STM32CubeF4.git
synced 2025-05-01 22:17:30 +08:00
96 lines
4.8 KiB
Plaintext
96 lines
4.8 KiB
Plaintext
![]() |
/**
|
||
|
@page CRC_Example Cyclic Redundancy Check Example
|
||
|
|
||
|
@verbatim
|
||
|
******************** (C) COPYRIGHT 2017 STMicroelectronics *******************
|
||
|
* @file CRC/CRC_Example/readme.txt
|
||
|
* @author MCD Application Team
|
||
|
* @brief Description of Cyclic Redundancy Check Example.
|
||
|
******************************************************************************
|
||
|
*
|
||
|
* Redistribution and use in source and binary forms, with or without modification,
|
||
|
* are permitted provided that the following conditions are met:
|
||
|
* 1. Redistributions of source code must retain the above copyright notice,
|
||
|
* this list of conditions and the following disclaimer.
|
||
|
* 2. Redistributions in binary form must reproduce the above copyright notice,
|
||
|
* this list of conditions and the following disclaimer in the documentation
|
||
|
* and/or other materials provided with the distribution.
|
||
|
* 3. Neither the name of STMicroelectronics nor the names of its contributors
|
||
|
* may be used to endorse or promote products derived from this software
|
||
|
* without specific prior written permission.
|
||
|
*
|
||
|
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
|
||
|
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
||
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
|
||
|
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
|
||
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
||
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
|
||
|
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
|
||
|
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
|
||
|
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
|
||
|
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
||
|
*
|
||
|
******************************************************************************
|
||
|
@endverbatim
|
||
|
|
||
|
@par Example Description
|
||
|
|
||
|
This example guides you through the different configuration steps by means of the
|
||
|
HAL API. The CRC (Cyclic Redundancy Check) calculation unit computes the CRC code
|
||
|
of a given buffer of 32-bit data words, using a fixed generator polynomial (0x4C11DB7).
|
||
|
|
||
|
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 100 MHz.
|
||
|
|
||
|
The CRC peripheral configuration is ensured by HAL_CRC_Init() function.
|
||
|
The latter is calling HAL_CRC_MspInit() function which core is implementing
|
||
|
the configuration of the needed CRC resources according to the used hardware (CLOCK).
|
||
|
You can update HAL_CRC_Init() input parameters to change the CRC configuration.
|
||
|
|
||
|
The calculated CRC code is stored in uwCRCValue variable
|
||
|
and compared with the expected one stored in uwExpectedCRCValue variable.
|
||
|
|
||
|
STM32 board LEDs are used to monitor the example status:
|
||
|
- LED4 (RED) is slowly blinking (1 sec. period) when an incorrect CRC value is calculated or in case of initialization error
|
||
|
- LED3 (GREEN) is ON when a correct CRC value is calculated
|
||
|
|
||
|
@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 The application needs to ensure that the SysTick time base is always set to 1 millisecond
|
||
|
to have correct HAL operation.
|
||
|
|
||
|
@par Directory contents
|
||
|
|
||
|
- CRC/CRC_Example/Inc/stm32f4xx_hal_conf.h HAL configuration file
|
||
|
- CRC/CRC_Example/Inc/stm32f4xx_it.h Interrupt handlers header file
|
||
|
- CRC/CRC_Example/Inc/main.h Header for main.c module
|
||
|
- CRC/CRC_Example/Src/stm32f4xx_it.c Interrupt handlers
|
||
|
- CRC/CRC_Example/Src/main.c Main program
|
||
|
- CRC/CRC_Example/Src/stm32f4xx_hal_msp.c HAL MSP module
|
||
|
- CRC/CRC_Example/Src/system_stm32f4xx.c STM32F4xx system source file
|
||
|
|
||
|
|
||
|
@par Hardware and Software environment
|
||
|
|
||
|
- This example runs on STM32F413xx devices.
|
||
|
|
||
|
- This example has been tested with an STMicroelectronics STM32F413H-DISCOVERY
|
||
|
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>
|
||
|
*/
|
||
|
|