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/**
@page RCC_CRS_Synchronization_IT RCC Clock Recovery Service example
@verbatim
******************************************************************************
* @file RCC/RCC_CRS_Synchronization_IT/readme.txt
* @author MCD Application Team
* @brief Description of the RCC Clock Recovery Service 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
Configuration of the clock recovery service (CRS) in Interrupt mode, using the RCC HAL API.
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 64 MHz.
Then, HSI48 and LSE oscillators are enabled.
In this example, as a first step a synchronization miss is raised when using a wrong synchronization
source (GPIO instead of LSE which is not configured). In a 2nd step, a reconfiguration is done to
use LSE and the correct synchronization.
In this test, this is the scenario:
- set the source to GPIO and then enable IT
- to provoke a SYNC event, call the software event generation function
- Interrupt is raised to indicate a SYNC MISS and then power on LED3
- in main program, wait for 1 sec and reconfigure source to LSE
- LED1 is power on when SYNC WARN is detected
- Increase tollerance (FELIM value) when SYNC WARN is detected
- At the end of the test LED2 should stay ON
Note: HSI48 frequency can be checked with oscilloscope using MCO PIN PA.08
@par Keywords
RCC, System, Clock Configuration, CRS, System clock, Oscillator, PLL
@par Directory contents
- RCC/RCC_CRS_Synchonization_IT/Inc/stm32wbxx_hal_conf.h HAL configuration file
- RCC/RCC_CRS_Synchonization_IT/Inc/stm32wbxx_it.h Interrupt handlers header file
- RCC/RCC_CRS_Synchonization_IT/Inc/main.h Header for main.c module
- RCC/RCC_CRS_Synchonization_IT/Src/stm32wbxx_it.c Interrupt handlers
- RCC/RCC_CRS_Synchonization_IT/Src/main.c Main program
- RCC/RCC_CRS_Synchonization_IT/Src/system_stm32wbxx.c STM32WBxx system source file
- RCC/RCC_CRS_Synchonization_IT/Src/stm32wbxx_hal_msp.c HAL MSP module
@par Hardware and Software environment
- This example runs on STM32WB55RGVx 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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