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Using TIM1 as a PWM input

Question asked by soldavin.keith.002 on Sep 4, 2014
Latest reply on Sep 4, 2014 by Clive One
I am trying to set up TIM1 on my STM32F407 to act as a PWM input but I'm not having any luck. I have successfully used TIM2 with an identical circuit but when I modify the code to run on TIM1 I never get the interrupt. Below is my setup and interrupt code:

static void Timer1Init(void)
{
    GPIO_InitTypeDef GPIO_InitStructure;
    TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;
    NVIC_InitTypeDef NVIC_InitStructure;
    TIM_ICInitTypeDef  TIM_ICInitStructure;
 
    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM1, ENABLE);
 
    // Set up the PW Input
    GPIO_InitStructure.GPIO_Pin   = GPIO_Pin_11;
    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_Init(GPIOA, &GPIO_InitStructure);
    GPIO_PinAFConfig(GPIOA, GPIO_PinSource11, GPIO_AF_TIM1);
 
    NVIC_InitStructure.NVIC_IRQChannel                      = TIM1_CC_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority    = configMAX_SYSCALL_INTERRUPT_PRIORITY-1;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority           = 0;
    NVIC_InitStructure.NVIC_IRQChannelCmd                   = ENABLE;
    NVIC_Init(&NVIC_InitStructure);
 
        // Set up the Timer Structure
    TIM_ICInitStructure.TIM_Channel     = TIM_Channel_4;
    TIM_ICInitStructure.TIM_ICPolarity  = TIM_ICPolarity_Rising;
    //TIM_ICInitStructure.TIM_ICPolarity    = TIM_ICPolarity_Falling;
    TIM_ICInitStructure.TIM_ICSelection = TIM_ICSelection_DirectTI;
    TIM_ICInitStructure.TIM_ICPrescaler = TIM_ICPSC_DIV1;
    TIM_ICInitStructure.TIM_ICFilter    = 0x0;
 
    TIM_PWMIConfig(TIM1, &TIM_ICInitStructure);
 
    /* Select the Input Trigger: TI2FP2 */
    TIM_SelectInputTrigger(TIM1, TIM_TS_TI2FP2);
 
    /* Select the slave Mode: Reset Mode */
    TIM_SelectSlaveMode(TIM1, TIM_SlaveMode_Reset);
    TIM_SelectMasterSlaveMode(TIM1,TIM_MasterSlaveMode_Enable);
 
    /* TIM enable counter */
    TIM_Cmd(TIM1, ENABLE);
 
    /* Enable the CC2 Interrupt Request */
    TIM_ITConfig(TIM1, TIM_IT_CC2, ENABLE);
}
 
void TIM1_CC_IRQHandler(void)
{
    portBASE_TYPE xHigherPriorityTaskWoken = pdFALSE;
    /* Clear Capture compare interrupt pending bit */
    TIM_ClearITPendingBit(TIM1, TIM_IT_CC2);
 
    /* Get the Input Capture value */
    pulseWidthTemp = TIM_GetCapture2(TIM1) - TIM_GetCapture1(TIM1);
    I1CTemp = TIM_GetCapture1(TIM1);
 
    xSemaphoreGiveFromISR(ScanComplete,&xHigherPriorityTaskWoken);
 
    if( xHigherPriorityTaskWoken != pdFALSE )
    {
        taskYIELD();
    }
}

Any thoughts as to why this would work with TIM2 but not TIM1? I understand that TIM1 is a different hardware configuration but I think I should have it set up correctly.

Thank you
Keith

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