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STM32F103RB TIM1 INPUT CAPTURE QUESTION?

Question asked by aiwu.jin on Sep 28, 2011
Latest reply on Sep 28, 2011 by Clive One
hi, dear Frs.
  now i want use the TIM1 ch1,ch2 to decode rf decoded . which is rf encode is diphase coded.  i use the PA8 use rf data stream input pin.  rf datarate is 9.6k. 
 now i step steps is as belows:

 

static void GPIO_Configuration(void)
{

  GPIO_InitTypeDef GPIO_InitStructure;
    
  /*GPIOA Configuration: TIM1 channel 1&2 as alternate function push-pull */
  /*GPIOA pin8/9 as general input */
  GPIO_InitStructure.GPIO_Pin   =  GPIO_Pin_8 | GPIO_Pin_9;
  GPIO_InitStructure.GPIO_Mode  = GPIO_Mode_IPU; //GPIO_Mode_IN_FLOATING;
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;

  GPIO_Init(GPIOA, &GPIO_InitStructure);

}

static void NVIC_Configuration(void)
{
  NVIC_InitTypeDef NVIC_InitStructure;

  /* Enable the TIM1 gloabal Interrupt */
  NVIC_InitStructure.NVIC_IRQChannel = TIM1_CC_IRQn;
  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;

  NVIC_Init(&NVIC_InitStructure);
}

static void RF_TIM1Init(void)
{
  

    RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM1||RCC_APB2Periph_GPIOA, ENABLE);
 
 GPIO_Configuration();

 TIM_DeInit(TIM1);
      /* -----------------------------------------------------------------------
    TIM1 Configuration:capture  40--200us signals with different duty cycles:
    TIM1CLK = 72 MHz, Prescaler = 0x0, TIM3 counter clock = 72MHz
    TIM1 ARR Register = 72 => TIM1 Frequency = TIM1 counter clock/(ARR + 1)
    TIM1 Frequency = 1us(1MHZ).

   
  ----------------------------------------------------------------------- */
   
      /* Time base configuration */
     TIM_TimeBaseStructure.TIM_Period = 65535;
     TIM_TimeBaseStructure.TIM_Prescaler = 72;
     TIM_TimeBaseStructure.TIM_ClockDivision = 0;
     TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;

 
 

  TIM_TimeBaseInit(TIM1,&TIM_TimeBaseStructure);

  TIM_ICInitStructure.TIM_Channel = TIM_Channel_2;
  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 = 2;
  TIM_ICInit(TIM1,&TIM_ICInitStructure);

  TIM_ICInitStructure.TIM_Channel = TIM_Channel_1;
  TIM_ICInitStructure.TIM_ICPolarity = TIM_ICPolarity_Falling;
  TIM_ICInitStructure.TIM_ICSelection  = TIM_ICSelection_IndirectTI;
  TIM_ICInitStructure.TIM_ICPrescaler  = TIM_ICPSC_DIV1;

  TIM_ICInit(TIM1,&TIM_ICInitStructure);

  TIM_ClearFlag(TIM1, TIM_FLAG_CC1||TIM_FLAG_CC2);

  TIM_ITConfig(TIM1,TIM_IT_CC1||TIM_IT_CC2,ENABLE);
  NVIC_Configuration();
  TIM_ARRPreloadConfig(TIM1, ENABLE);
  TIM_CCxCmd(TIM1,TIM_Channel_1||TIM_Channel_2,ENABLE);
  TIM_Cmd(TIM1, ENABLE);

}

but the can not enter the TIM1 cc1 intterupt isr.
i check the NVIC. the 
TIM1%20NVIC.JPG
TIM1%20REG.JPG

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