68 lines
2.7 KiB
Plaintext
68 lines
2.7 KiB
Plaintext
/**
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@page RCC_UseHSI_PLLasSystemClock RCC example
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@verbatim
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******************** (C) COPYRIGHT 2016 STMicroelectronics *******************
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* @file Examples_LL/RCC/RCC_UseHSI_PLLasSystemClock/readme.txt
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* @author MCD Application Team
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* @brief Description of the RCC_UseHSI_PLLasSystemClock example.
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******************************************************************************
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* @attention
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*
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* Copyright (c) 2016 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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Modification of the PLL parameters in run time.
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In this example, the toggling frequency of the green LED2 depends on the system clock
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frequency and, each time the user-button is pressed, the PLL switches between two configurations.
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This make the LED2 blinking speed to highlight the system clock frequency changes.
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In this example, after start-up, SYSCLK is configured to the max frequency using the PLL with
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HSE as clock source.
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Then, at user-button press, an automatic switch is done between PLL with HSI as clock source (SYSCLK
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set to 32MHz) and PLL with HSI as clock source (SYSCLK set to 64MHz).
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LED2 will toggle differently between the 2 configurations (quick toggle with HSI configuration at 64MHz).
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To detect a problem with PLL configuration, switch USE_TIMEOUT can be enabled. Then in case of issues,
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LED2 will toggle every 1 second.
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Note: "uwFrequency" variable can be added in LiveWatch to monitor the system clock frequency.
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@par Directory contents
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- RCC/RCC_UseHSI_PLLasSystemClock/Inc/stm32f1xx_it.h Interrupt handlers header file
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- RCC/RCC_UseHSI_PLLasSystemClock/Inc/main.h Header for main.c module
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- RCC/RCC_UseHSI_PLLasSystemClock/Inc/stm32_assert.h Template file to include assert_failed function
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- RCC/RCC_UseHSI_PLLasSystemClock/Src/stm32f1xx_it.c Interrupt handlers
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- RCC/RCC_UseHSI_PLLasSystemClock/Src/main.c Main program
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- RCC/RCC_UseHSI_PLLasSystemClock/Src/system_stm32f1xx.c STM32F1xx system source file
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@par Hardware and Software environment
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- This example runs on STM32F103xB devices.
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- This example has been tested with STM32F103RB-Nucleo 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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