RCC_Example

  ******************** (C) COPYRIGHT 2010 STMicroelectronics *******************
  * @file    RCC/readme.txt 
  * @author  MCD Application Team
  * @version V3.4.0
  * @date    10/15/2010
  * @brief   Description of the RCC Example.
  ******************************************************************************
  * THE PRESENT FIRMWARE WHICH IS FOR GUIDANCE ONLY AIMS AT PROVIDING CUSTOMERS
  * WITH CODING INFORMATION REGARDING THEIR PRODUCTS IN ORDER FOR THEM TO SAVE
  * TIME. AS A RESULT, STMICROELECTRONICS SHALL NOT BE HELD LIABLE FOR ANY
  * DIRECT, INDIRECT OR CONSEQUENTIAL DAMAGES WITH RESPECT TO ANY CLAIMS ARISING
  * FROM THE CONTENT OF SUCH FIRMWARE AND/OR THE USE MADE BY CUSTOMERS OF THE
  * CODING INFORMATION CONTAINED HEREIN IN CONNECTION WITH THEIR PRODUCTS.
  ******************************************************************************
   
Example Description

This example shows how to configure the System clock(SYSCLK) to have different frequencies: 24MHz, 36MHz, 48MHz, 56MHz and 72MHz (common frequencies that covers the major of the applications). The SYSCLK frequency is selected by user in main.h file.

It shows how to use, for debug purpose, the RCC_GetClocksFreq function to retrieve the current status and frequencies of different on chip clocks. You can see the RCC_ClockFreq structure content, which hold the frequencies of different on chip clocks, using your toolchain debugger.

This example handles also the High Speed External clock (HSE) failure detection: when the HSE clock disappears (broken or disconnected external Quartz); HSE, PLL are disabled (but no change on PLL config), HSI selected as system clock source and an interrupt (NMI) is generated. In the NMI ISR, the HSE, HSE ready interrupt are enabled and once HSE clock recover, the HSERDY interrupt is generated and in the RCC ISR routine the system clock is reconfigured to its previous state (before HSE clock failure). You can monitor the HSE clock on the MCO pin (PA.08).

Four LEDs are toggled with a timing defined by the Delay function.

Note:
To adjust the External High Speed oscillator (HSE) Startup Timeout value, use HSEStartUp_TimeOut variable defined in the stm32f10x.h file.
Directory contents
Hardware and Software environment
How to use it ?

In order to make the program work, you must do the following :

Tip: You can tailor the provided project template to run this example, for more details please refer to "stm32f10x_stdperiph_lib_um.chm" user manual; select "Peripheral Examples" then follow the instructions provided in "How to proceed" section.

Note:
  • Low-density Value line devices are STM32F100xx microcontrollers where the Flash memory density ranges between 16 and 32 Kbytes.
  • Low-density devices are STM32F101xx, STM32F102xx and STM32F103xx microcontrollers where the Flash memory density ranges between 16 and 32 Kbytes.
  • Medium-density Value line devices are STM32F100xx microcontrollers where the Flash memory density ranges between 64 and 128 Kbytes.
  • Medium-density devices are STM32F101xx, STM32F102xx and STM32F103xx microcontrollers where the Flash memory density ranges between 64 and 128 Kbytes.
  • High-density Value line devices are STM32F100xx microcontrollers where the Flash memory density ranges between 256 and 512 Kbytes.
  • High-density devices are STM32F101xx and STM32F103xx microcontrollers where the Flash memory density ranges between 256 and 512 Kbytes.
  • XL-density devices are STM32F101xx and STM32F103xx microcontrollers where the Flash memory density ranges between 512 and 1024 Kbytes.
  • Connectivity line devices are STM32F105xx and STM32F107xx microcontrollers.

© COPYRIGHT 2010 STMicroelectronics

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