STM32F407VGT6 PWM input does not work

[ruthie.ma Senior Engineer]

STM32F407VGT6
TIM3_CH3(PB0) is PWM output and it works fine
TIM3_CH1(PB4) is PWM input and it doesn’t work

 

Here is configuration.

GPIO_InitTypeDef GPIO_InitStructure;
TIM_ICInitTypeDef  TIM_ICInitStructure;
RCC_AHB1PeriphClockCmd( RCC_AHB1Periph_GPIOB, ENABLE);
GPIO_PinAFConfig(GPIOB,GPIO_PinSource4,GPIO_AF_TIM3);
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_4;
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(GPIOB, &GPIO_InitStructure);

RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3,ENABLE);
TIM_ICInitStructure.TIM_Channel = TIM_Channel_1;     
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 = 0x0;
  TIM_PWMIConfig(TIM3, &TIM_ICInitStructure);
  TIM_SelectInputTrigger(TIM3, TIM_TS_TI1FP1);
  TIM_SelectSlaveMode(TIM3, TIM_SlaveMode_Reset);
  TIM_SelectMasterSlaveMode(TIM3, TIM_MasterSlaveMode_Enable);
  TIM_Cmd(TIM3, ENABLE);

Only CCR2 contains correct PWM pulse width and CCR1 PWM pulse width is always zero.

Any idea?

[Author]

Posts