Lập trình Encoder STM32

Hôm nay mình giới thiệu cách đọc encoder từ motor 

Để đảm bảo tín hiệu có thể cách  ly qua opto TLP2395 ..

void Config_encoder_timer5(void)
{
     TIM_TimeBaseInitTypeDef TIM_TimeBaseInitStructure;
    TIM_ICInitTypeDef TIM_ICInitStructure;
  GPIO_InitTypeDef  GPIO_InitStructure;
    NVIC_InitTypeDef NVIC_InitStructure;
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM5, ENABLE);
    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA , ENABLE);

  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0|GPIO_Pin_1;
  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_UP ;    
  GPIO_Init(GPIOA, &GPIO_InitStructure);

    TIM_TimeBaseInitStructure.TIM_Prescaler=0;
  TIM_TimeBaseInitStructure.TIM_Period=65535;
  TIM_TimeBaseInitStructure.TIM_ClockDivision=TIM_CKD_DIV1;
    TIM_TimeBaseInitStructure.TIM_CounterMode = TIM_CounterMode_Up;//
  TIM_TimeBaseInit(TIM5, &TIM_TimeBaseInitStructure);
  
    GPIO_PinAFConfig(GPIOA, GPIO_PinSource0, GPIO_AF_TIM5); // tim5
  GPIO_PinAFConfig(GPIOA, GPIO_PinSource1, GPIO_AF_TIM5);

        
  TIM_ICInitStructure.TIM_Channel=TIM_Channel_1|TIM_Channel_2;
  TIM_ICInitStructure.TIM_ICPolarity=TIM_ICPolarity_Falling;
  TIM_ICInitStructure.TIM_ICFilter=200;
  TIM_ICInitStructure.TIM_ICSelection=TIM_ICSelection_DirectTI;
  TIM_ICInit(TIM5, &TIM_ICInitStructure);    
  TIM_EncoderInterfaceConfig(TIM5, TIM_EncoderMode_TI12, TIM_ICPolarity_Falling, TIM_ICPolarity_Falling);
  TIM_ClearITPendingBit(TIM5, TIM_IT_Update);
  TIM_ITConfig(TIM5, TIM_IT_Update, ENABLE);
  TIM_Cmd(TIM5,ENABLE);     
  TIM_SetCounter(TIM5, 10000); 
   ///////////////////////////
        TIM5->EGR = 0;           // Generate an update event
    TIM5->CR1 = 1;           // Enable the counter
   /////////////////
  NVIC_PriorityGroupConfig(NVIC_PriorityGroup_1);
  NVIC_InitStructure.NVIC_IRQChannel = TIM5_IRQn;
  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 4;
  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
  NVIC_Init(&NVIC_InitStructure);
}
ở đây mình dùng 2 kênh là PA0,PA1 để đọc encoder 

Hàm ngắt encoder 

void TIM5_IRQHandler(void)
{
  TIM_ClearITPendingBit(TIM5, TIM_IT_Update);
    if(TIM5->CR1&TIM_CounterMode_Down)num_over_t5--;    
    else num_over_t5++;    
}

giá trị lưu vào num_over_t5