Output Compare and Input Capture

[Fabio Romeo]

Posted on August 01, 2017 at 17:51

STM32F429II

Hi everybody. I have a question about the

coexistence of OC and IC in the same Timer. For example,  I have to use PH10 as OC and PH11 as IC. As Alternate function respectively CH1 and CH2 of Timer 5. 

The IC works for PH11. When I try to set the OC even the IC stops working.

[waclawek.jan]

Posted on August 01, 2017 at 18:21

Then you do something wrong.

Read out and post the timer registers' content.

JW

[Tesla DeLorean]

Posted on August 01, 2017 at 19:40

>>

I have a question about the

coexistence of OC and IC in the same Timer.

Should work, processor will do what you tell it, show us what you're telling it.

[Fabio Romeo]

Posted on August 02, 2017 at 12:46

You're both right :

void TIM5_Config(void)

{

  /* GPIOH clock enable */

  RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOH, ENABLE);

  GPIO_InitTypeDef GPIO_InitStructure;

  GPIO_InitStructure.GPIO_Pin =  GPIO_Pin_11; // used as Input Capture

  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;

  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;

  GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;

  GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL; //GPIO_PuPd_NOPULL;

  GPIO_Init(GPIOH, &GPIO_InitStructure);

  GPIO_PinAFConfig(GPIOH, GPIO_PinSource11, GPIO_AF_TIM5);  // Connect TIM pins to AF2

  GPIO_InitStructure.GPIO_Pin =  GPIO_Pin_10; // used as Output Compare

  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;

  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;

  GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;

  GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL; //GPIO_PuPd_NOPULL;

  GPIO_Init(GPIOH, &GPIO_InitStructure);

  GPIO_PinAFConfig(GPIOH, GPIO_PinSource10, GPIO_AF_TIM5);  // Connect TIM pins to AF2

  RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM5, ENABLE); //   TIM5 clock enable

  TIM_ICInitTypeDef  TIM_InputCaptureInitStructure;

  TIM_InputCaptureInitStructure.TIM_Channel = TIM_Channel_2;

  TIM_InputCaptureInitStructure.TIM_ICPolarity = TIM_ICPolarity_Falling;

  TIM_InputCaptureInitStructure.TIM_ICSelection = TIM_ICSelection_DirectTI;

  TIM_InputCaptureInitStructure.TIM_ICPrescaler = TIM_ICPSC_DIV1;

 // TIM_InputCaptureInitStructure.TIM_ICFilter = 0x0;

  TIM_ICInit(TIM5, &TIM_InputCaptureInitStructure);

  TIM_OCInitTypeDef TIM_OCInitStructure;

  TIM_OCStructInit (&TIM_OCInitStructure);

/* just use basic Output Compare Mode*/

  TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_Active;

 /* set the initial match interval for CC1 */

  TIM_OCInitStructure.TIM_Pulse = 20000;

  TIM_OC1Init (TIM5, &TIM_OCInitStructure);

  // Clear CC1 Flag

  TIM_ClearFlag(TIM5, TIM_FLAG_CC1 );

    // Clear CC2 Flag

  TIM_ClearFlag(TIM5, TIM_FLAG_CC2 );

  NVIC_InitTypeDef NVIC_InitStructure;

  NVIC_InitStructure.NVIC_IRQChannel = TIM5_IRQn ;

  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;

  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;

  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;   // Enable the TIM5 global Interrupt

  NVIC_Init(&NVIC_InitStructure);

   /* Select the slave Mode: Reset Mode */

  TIM_SelectSlaveMode(TIM5, TIM_SlaveMode_Reset);

  TIM_SelectMasterSlaveMode(TIM5, TIM_MasterSlaveMode_Enable);

  //Enable CC2 interrupt

  TIM_ITConfig(TIM5,TIM_IT_CC2 | TIM_IT_CC1, ENABLE);

  //EnableTIM5

  TIM_Cmd(TIM5,ENABLE);

}

[Vangelis Fortounas]

Posted on August 02, 2017 at 13:46

Hello!

You did not initialize

TIM5  time base (TIM_TimeBaseInit)  , prescaler , auto reload register..

[Fabio Romeo]

Posted on August 02, 2017 at 14:13

Sorry I put even the timBase configuration. but nothing changed

static void TIM5_Config(void)

{

// TIM_DeInit(TIM5 );

  /* GPIOH clock enable */

  RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOH, ENABLE);

  GPIO_InitTypeDef GPIO_InitStructure;

  GPIO_InitStructure.GPIO_Pin =  GPIO_Pin_11; // used as Input Capture

  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;

  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;

  GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;

  GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL; //GPIO_PuPd_NOPULL;

  GPIO_Init(GPIOH, &GPIO_InitStructure);

  GPIO_PinAFConfig(GPIOH, GPIO_PinSource11, GPIO_AF_TIM5);  // Connect TIM pins to AF2

  GPIO_InitStructure.GPIO_Pin =  GPIO_Pin_10; // used as Output Compare

  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;

  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;

  GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;

  GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL; //GPIO_PuPd_NOPULL;

  GPIO_Init(GPIOH, &GPIO_InitStructure);

  GPIO_PinAFConfig(GPIOH, GPIO_PinSource10, GPIO_AF_TIM5);  // Connect TIM pins to AF2

  RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM5, ENABLE); //   TIM5 clock enable

  TIM_ICInitTypeDef  TIM_InputCaptureInitStructure;

  TIM_InputCaptureInitStructure.TIM_Channel = TIM_Channel_2;

  TIM_InputCaptureInitStructure.TIM_ICPolarity = TIM_ICPolarity_Falling;

  TIM_InputCaptureInitStructure.TIM_ICSelection = TIM_ICSelection_DirectTI;

  TIM_InputCaptureInitStructure.TIM_ICPrescaler = TIM_ICPSC_DIV1;

 // TIM_InputCaptureInitStructure.TIM_ICFilter = 0x0;

  TIM_ICInit(TIM5, &TIM_InputCaptureInitStructure);

  TIM_OCInitTypeDef TIM_OCInitStructure;

  TIM_OCStructInit (&TIM_OCInitStructure);

// just use basic Output Compare Mode

  TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_Active;

 // set the initial match interval for CC1

  TIM_OCInitStructure.TIM_Pulse = 20000;

  TIM_OC1Init (TIM5, &TIM_OCInitStructure);

 

 

  TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;

  TIM_TimeBaseStructure.TIM_Period = 65535;

  TIM_TimeBaseStructure.TIM_Prescaler = 1;

  TIM_TimeBaseStructure.TIM_ClockDivision = 0;

  TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;

  TIM_TimeBaseInit(TIM5, &TIM_TimeBaseStructure);

  // Clear CC1 Flag

  TIM_ClearFlag(TIM5, TIM_FLAG_CC1 );

    // Clear CC2 Flag

  TIM_ClearFlag(TIM5, TIM_FLAG_CC2  );

  NVIC_InitTypeDef NVIC_InitStructure;

  NVIC_InitStructure.NVIC_IRQChannel = TIM5_IRQn ;

  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;

  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;

  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;   // Enable the TIM5 global Interrupt

  NVIC_Init(&NVIC_InitStructure);

   /* Select the slave Mode: Reset Mode */

  TIM_SelectSlaveMode(TIM5, TIM_SlaveMode_Reset);

  TIM_SelectMasterSlaveMode(TIM5, TIM_MasterSlaveMode_Enable);

  //Enable CC2 interrupt

  TIM_ITConfig(TIM5,TIM_IT_CC2 | TIM_IT_CC1, ENABLE);//| TIM_IT_CC1

  //EnableTIM5

  TIM_Cmd(TIM5,ENABLE);

}

[waclawek.jan]

Posted on August 02, 2017 at 14:37

TIM_SelectSlaveMode(TIM5, TIM_SlaveMode_Reset);

Without having set TRGI source in TIMx_SMCR.TS, this defaults to Internal Trigger 0. Have you properly initialized the timer to which this links to output some reasonable TRGO? If not, this may hold this timer in reset indefinitely.

JW

[Vangelis Fortounas]

Posted on August 02, 2017 at 15:37

So If your intention is to have your timer as slave then do what

Waclawek.Jan

suggested .If not, call this TIM_SelectSlaveMode(TIM5, 0);or left it at it's default value