view libs/STM32F10x_StdPeriph_Lib_V3.5.0/Project/STM32F10x_StdPeriph_Examples/RTC/LSI_Calib/main.c @ 85:18b154c447bb

Add note about 1-wire wiring
author Daniel O'Connor <darius@dons.net.au>
date Thu, 12 Mar 2015 23:22:11 +1030
parents c59513fd84fb
children
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/**
  ******************************************************************************
  * @file    RTC/LSI_Calib/main.c 
  * @author  MCD Application Team
  * @version V3.5.0
  * @date    08-April-2011
  * @brief   Main program body
  ******************************************************************************
  * @attention
  *
  * 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.
  *
  * <h2><center>&copy; COPYRIGHT 2011 STMicroelectronics</center></h2>
  ******************************************************************************
  */ 

/* Includes ------------------------------------------------------------------*/
#include "main.h"
#include <stdio.h>

/** @addtogroup STM32F10x_StdPeriph_Examples
  * @{
  */

/** @addtogroup RTC_LSI_Calib
  * @{
  */ 

/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/
#define RTCClockOutput_Enable  /* RTC Clock/64 is output on tamper pin(PC.13) */

/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/

TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;
TIM_ICInitTypeDef  TIM_ICInitStructure;
RCC_ClocksTypeDef RCC_Clocks;
__IO uint32_t PeriodValue = 0,  LsiFreq = 0;
__IO uint32_t OperationComplete = 0;

/* Private function prototypes -----------------------------------------------*/
void RTC_Configuration(void);
void NVIC_Configuration(void);

/* Private functions ---------------------------------------------------------*/

/**
  * @brief  Main program.
  * @param  None
  * @retval None
  */
int main(void)
{
  /*!< At this stage the microcontroller clock setting is already configured, 
       this is done through SystemInit() function which is called from startup
       file (startup_stm32f10x_xx.s) before to branch to application main.
       To reconfigure the default setting of SystemInit() function, refer to
       system_stm32f10x.c file
     */     

  /* Initialize LEDs and Key Button mounted on STM3210X-EVAL board */       
  STM_EVAL_LEDInit(LED1);
  STM_EVAL_LEDInit(LED2);
  STM_EVAL_PBInit(BUTTON_KEY, BUTTON_MODE_GPIO);

  /* RTC Configuration */
  RTC_Configuration();

  /* Wait until Key Push button is pressed */
  while (STM_EVAL_PBGetState(BUTTON_KEY) != 0)
  {
  }

  /* Get the Frequency value */
  RCC_GetClocksFreq(&RCC_Clocks);

  /* Enable TIM5 APB1 clocks */
  RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM5, ENABLE);

  /* Connect internally the TM5_CH4 Input Capture to the LSI clock output */
  GPIO_PinRemapConfig(GPIO_Remap_TIM5CH4_LSI, ENABLE);

  /* TIM5 Time base configuration */
  TIM_TimeBaseStructure.TIM_Prescaler = 0;
  TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
  TIM_TimeBaseStructure.TIM_Period = 0xFFFF;
  TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1;
  TIM_TimeBaseInit(TIM5, &TIM_TimeBaseStructure);

  /* TIM5 Channel4 Input capture Mode configuration */
  TIM_ICInitStructure.TIM_Channel = TIM_Channel_4;
  TIM_ICInitStructure.TIM_ICPolarity = TIM_ICPolarity_Rising;
  TIM_ICInitStructure.TIM_ICSelection = TIM_ICSelection_DirectTI;
  TIM_ICInitStructure.TIM_ICPrescaler = TIM_ICPSC_DIV1;
  TIM_ICInitStructure.TIM_ICFilter = 0;
  TIM_ICInit(TIM5, &TIM_ICInitStructure);

  /* Reinitialize the index for the interrupt */
  OperationComplete = 0;

  /* Enable the TIM5 Input Capture counter */
  TIM_Cmd(TIM5, ENABLE);
  /* Reset all TIM5 flags */
  TIM5->SR = 0;
  /* Enable the TIM5 channel 4 */
  TIM_ITConfig(TIM5, TIM_IT_CC4, ENABLE);

  /* NVIC configuration */
  NVIC_Configuration();

  /* Wait the TIM5 measuring operation to be completed */
  while (OperationComplete != 2)
  {}

  /* Compute the actual frequency of the LSI. (TIM5_CLK = 2 * PCLK1)  */
  if (PeriodValue != 0)
  {
#if defined (STM32F10X_LD_VL) || defined (STM32F10X_MD_VL) || defined (STM32F10X_HD_VL)
    LsiFreq = (uint32_t)((uint32_t)(RCC_Clocks.PCLK1_Frequency) / (uint32_t)PeriodValue);
#else
    LsiFreq = (uint32_t)((uint32_t)(RCC_Clocks.PCLK1_Frequency * 2) / (uint32_t)PeriodValue);
#endif
  }

  /* Adjust the RTC prescaler value */
  RTC_SetPrescaler(LsiFreq - 1);

  /* Wait until last write operation on RTC registers has finished */
  RTC_WaitForLastTask();

  /* Turn on LED2 */
  STM_EVAL_LEDOn(LED2);

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

}

/**
  * @brief  Configures the nested vectored interrupt controller.
  * @param  None
  * @retval None
  */
void NVIC_Configuration(void)
{
  NVIC_InitTypeDef NVIC_InitStructure;

  /* Configure one bit for preemption priority */
  NVIC_PriorityGroupConfig(NVIC_PriorityGroup_1);

  /* Enable the RTC Interrupt */
  NVIC_InitStructure.NVIC_IRQChannel = RTC_IRQn;
  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
  NVIC_Init(&NVIC_InitStructure);

  /* Enable the TIM5 Interrupt */
  NVIC_InitStructure.NVIC_IRQChannel = TIM5_IRQn;
  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 2;
  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
  NVIC_Init(&NVIC_InitStructure);
}

/**
  * @brief  Configures the RTC.
  * @param  None
  * @retval None
  */
void RTC_Configuration(void)
{
  /* Enable PWR and BKP clocks */
  RCC_APB1PeriphClockCmd(RCC_APB1Periph_PWR | RCC_APB1Periph_BKP, ENABLE);

  /* Allow access to BKP Domain */
  PWR_BackupAccessCmd(ENABLE);

  /* Reset Backup Domain */
  BKP_DeInit();

  /* Enable the LSI OSC */
  RCC_LSICmd(ENABLE);
  /* Wait till LSI is ready */
  while (RCC_GetFlagStatus(RCC_FLAG_LSIRDY) == RESET)
  {}
  /* Select the RTC Clock Source */
  RCC_RTCCLKConfig(RCC_RTCCLKSource_LSI);

  /* Enable RTC Clock */
  RCC_RTCCLKCmd(ENABLE);

  /* Wait for RTC registers synchronization */
  RTC_WaitForSynchro();

  /* Wait until last write operation on RTC registers has finished */
  RTC_WaitForLastTask();

  /* Enable the RTC Second */
  RTC_ITConfig(RTC_IT_SEC, ENABLE);

  /* Wait until last write operation on RTC registers has finished */
  RTC_WaitForLastTask();

  /* Set RTC prescaler: set RTC period to 1sec */
  RTC_SetPrescaler(40000);

  /* Wait until last write operation on RTC registers has finished */
  RTC_WaitForLastTask();

  /* To output second signal on Tamper pin, the tamper functionality
       must be disabled (by default this functionality is disabled) */
  BKP_TamperPinCmd(DISABLE);

  /* Enable the RTC Second Output on Tamper Pin */
  BKP_RTCOutputConfig(BKP_RTCOutputSource_Second);
}

/**
  * @brief  Increments OperationComplete variable and return its value 
  *         before increment operation.
  * @param  None
  * @retval OperationComplete value before increment
  */
uint32_t IncrementVar_OperationComplete(void)
{
  OperationComplete++;
  
  return (uint32_t)(OperationComplete -1);
}

/**
  * @brief  Returns OperationComplete value.
  * @param  None
  * @retval OperationComplete value
  */
uint32_t GetVar_OperationComplete(void)
{
  return (uint32_t)OperationComplete;
}

/**
  * @brief  Sets the PeriodValue variable with input parameter.
  * @param  Value: Value of PeriodValue to be set.
  * @retval None
  */
void SetVar_PeriodValue(uint32_t Value)
{
  PeriodValue = (uint32_t)(Value);
}

#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 2011 STMicroelectronics *****END OF FILE****/