STM32F0xx_StdPeriph_Examples/RCC/RCC_Example/main.c

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/**
  ******************************************************************************
  * @file    RCC/RCC_Example/main.c 
  * @author  MCD Application Team
  * @version V1.4.0
  * @date    24-July-2014
  * @brief   Main program body
  ******************************************************************************
  * @attention
  *
  * <h2><center>&copy; COPYRIGHT 2014 STMicroelectronics</center></h2>
  *
  * Licensed under MCD-ST Liberty SW License Agreement V2, (the "License");
  * You may not use this file except in compliance with the License.
  * You may obtain a copy of the License at:
  *
  *        http://www.st.com/software_license_agreement_liberty_v2
  *
  * Unless required by applicable law or agreed to in writing, software 
  * distributed under the License is distributed on an "AS IS" BASIS, 
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  *
  ******************************************************************************
  */

/* Includes ------------------------------------------------------------------*/
#include "main.h"

/** @addtogroup STM32F0xx_StdPeriph_Examples
  * @{
  */

/** @addtogroup RCC_Example
  * @{
  */

/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/
/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
/* Private function prototypes -----------------------------------------------*/
/* Private functions ---------------------------------------------------------*/

/**
  * @brief  Main program.
  * @param  None
  * @retval None
  */
int main(void)
{
 GPIO_InitTypeDef GPIO_InitStructure;
 NVIC_InitTypeDef NVIC_InitStructure;
 RCC_ClocksTypeDef RCC_ClockFreq;

  /*!< At this stage the microcontroller clock setting is already configured, 
       this is done through SystemInit() function which is called from startup
       file (startup_stm32f0xx.s) before to branch to application main.
       To reconfigure the default setting of SystemInit() function, refer to
       system_stm32f0xx.c file
     */     

  /* Initialize Leds mounted on STM32072B-EVAL*/
  STM_EVAL_LEDInit(LED3);
  STM_EVAL_LEDInit(LED4);

  /* Turn on LED3 and LED4 */
  STM_EVAL_LEDOn(LED3);
  STM_EVAL_LEDOn(LED4);

  /* This function fills the RCC_ClockFreq structure with the current
     frequencies of different on chip clocks (for debug purpose) **************/
  RCC_GetClocksFreq(&RCC_ClockFreq);

  /* Enable Clock Security System(CSS): this will generate an NMI exception
  when HSE clock fails *****************************************************/
  RCC_ClockSecuritySystemCmd(ENABLE);

  /* Enable and configure RCC global IRQ channel, will be used to manage HSE ready 
     and PLL ready interrupts. 
     These interrupts are enabled in stm32f0xx_it.c file **********************/
#ifdef USE_STM320518_EVAL
  NVIC_InitStructure.NVIC_IRQChannel = RCC_IRQn;
#else 
  NVIC_InitStructure.NVIC_IRQChannel = RCC_CRS_IRQn; 
#endif /* USE_STM320518_EVAL */
  NVIC_InitStructure.NVIC_IRQChannelPriority = 0;
  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
  NVIC_Init(&NVIC_InitStructure);

  /* Output HSE clock on MCO1 pin(PA8) ****************************************/     
  /* Enable the GPIOA Clock */
  RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOA, ENABLE);

  /* MCO pin configuration: PA8 */
  GPIO_InitStructure.GPIO_Mode  = GPIO_Mode_AF;
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
  GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
  GPIO_InitStructure.GPIO_PuPd  = GPIO_PuPd_UP;
  GPIO_InitStructure.GPIO_Pin   = GPIO_Pin_8;
  GPIO_Init(GPIOA, &GPIO_InitStructure);

  GPIO_PinAFConfig(GPIOA, GPIO_PinSource8, GPIO_AF_0);

  /* Output System Clock on MCO pin */
#ifdef USE_STM320518_EVAL
  RCC_MCOConfig(RCC_MCOSource_SYSCLK); 
#else 
  RCC_MCOConfig(RCC_MCOSource_SYSCLK, RCC_MCOPrescaler_1);  
#endif /* USE_STM320518_EVAL */   

  while (1)
  {
    /* Toggle LED4 */
    STM_EVAL_LEDToggle(LED4);

    /* Insert a delay */
    Delay(0x4FFFF);

    /* Toggle LED3 */
    STM_EVAL_LEDToggle(LED3);

    /* Insert a delay */
    Delay(0x3FFFF);
  }
}

/**
  * @brief  Inserts a delay time.
  * @param  nCount: specifies the delay time length.
  * @retval None
  */
void Delay(__IO uint32_t nCount)
{
  /* Decrement nCount value */
  while (nCount != 0)
  {
    nCount--;
  }
}

#ifdef  USE_FULL_ASSERT

/**
  * @brief  Reports the name of the source file and the source line number
  *         where the assert_param error has occurred.
  * @param  file: pointer to the source file name
  * @param  line: assert_param error line source number
  * @retval None
  */
void assert_failed(uint8_t* file, uint32_t line)
{ 
  /* User can add his own implementation to report the file name and line number,
     ex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */

  /* Infinite loop */
  while (1)
  {
  }
}
#endif

/**
  * @}
  */

/**
  * @}
  */

/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/