Encoder mode with input capture ?

[goktug]

I want to measure speed of motor precisely with encoder pulses and for that I saw this topic

https://community.st.com/s/question/0D50X00009fDstgSAC/can-you-combine-encoder-and-input-capture-both-from-the-same-pin

@Werner D�hn​  @akosodry​ 

and from what I understand here , encoder mode internally triggering another input capture timer

My questions is ;

my encoder has 360 line but multiplex by 4 because of two channel ,so it becomes 1440 puls for one revolution.

I get 1440 puls from timer 4->CNT register but captured2 value from tim5 callback function give 360 puls is it correct ? or is it missing someting ?

and also my rpm measurement range 10-100 RPM so I'm deal with very low frequencies and I'm okay with any suggestions for precise speed measurement in that frequencie range.

Thanks in advance for any solution

/* USER CODE BEGIN 0 */
void HAL_TIM_IC_CaptureCallback(TIM_HandleTypeDef *htim)
{
  if (htim->Channel == HAL_TIM_ACTIVE_CHANNEL_1)
  {
	  PPMValue_Prev = PPMValue;
	  PPMValue = HAL_TIM_ReadCapturedValue(htim, TIM_CHANNEL_1);
      PPM = (PPMValue >= PPMValue_Prev) ? (PPMValue - PPMValue_Prev) : (UINT16_MAX - PPMValue_Prev + PPMValue);
    
      captured2++;
 }
}
 
  MX_GPIO_Init();
  MX_TIM4_Init();
  MX_TIM5_Init();
  MX_USART2_UART_Init();
  /* USER CODE BEGIN 2 */
  HAL_TIM_Encoder_Start(&htim4,TIM_CHANNEL_ALL);
  HAL_TIM_IC_Start_IT(&htim5, TIM_CHANNEL_1);
 
 
  /* USER CODE END 2 */
 
  /* Infinite loop */
  /* USER CODE BEGIN WHILE */
int i = 0;
int a=0;
  while (1)
  {
  /* USER CODE END WHILE */
 
  /* USER CODE BEGIN 3 */
 
	  i = TIM4->CNT;
	  a=TIM5->CCR1;
HAL_UART_Transmit(&huart2, (uint8_t*)txData, sprintf(txData, "%d\t%d\t%d\t%d\t%d\r\n", a,i,PPM,captured,captured2), 500);
 
  }
  /* USER CODE END 3 */
 
 
 
/* TIM4 init function */
static void MX_TIM4_Init(void)
{
 
  TIM_Encoder_InitTypeDef sConfig;
  TIM_MasterConfigTypeDef sMasterConfig;
 
  htim4.Instance = TIM4;
  htim4.Init.Prescaler = 0;
  htim4.Init.CounterMode = TIM_COUNTERMODE_UP;
  htim4.Init.Period = 1-1;
  htim4.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;
  sConfig.EncoderMode = TIM_ENCODERMODE_TI12;
  sConfig.IC1Polarity = TIM_ICPOLARITY_RISING;
  sConfig.IC1Selection = TIM_ICSELECTION_DIRECTTI;
  sConfig.IC1Prescaler = TIM_ICPSC_DIV1;
  sConfig.IC1Filter = 5;
  sConfig.IC2Polarity = TIM_ICPOLARITY_RISING;
  sConfig.IC2Selection = TIM_ICSELECTION_DIRECTTI;
  sConfig.IC2Prescaler = TIM_ICPSC_DIV1;
  sConfig.IC2Filter = 5;
 
 
  sMasterConfig.MasterOutputTrigger = TIM_TRGO_OC1;
  sMasterConfig.MasterSlaveMode = TIM_MASTERSLAVEMODE_DISABLE;
  
 
}
 
/* TIM5 init function */
static void MX_TIM5_Init(void)
{
 
  TIM_ClockConfigTypeDef sClockSourceConfig;
  TIM_SlaveConfigTypeDef sSlaveConfig;
  TIM_MasterConfigTypeDef sMasterConfig;
  TIM_IC_InitTypeDef sConfigIC;
 
  htim5.Instance = TIM5;
  htim5.Init.Prescaler = 84-1;
  htim5.Init.CounterMode = TIM_COUNTERMODE_UP;
  htim5.Init.Period = 0xffff-1;
  htim5.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;
 
 
  sClockSourceConfig.ClockSource = TIM_CLOCKSOURCE_INTERNAL;
 
 
  sSlaveConfig.SlaveMode = TIM_SLAVEMODE_DISABLE;
  sSlaveConfig.InputTrigger = TIM_TS_ITR2;
  
 
  sMasterConfig.MasterOutputTrigger = TIM_TRGO_RESET;
  sMasterConfig.MasterSlaveMode = TIM_MASTERSLAVEMODE_DISABLE;
 
  sConfigIC.ICPolarity = TIM_INPUTCHANNELPOLARITY_RISING;
  sConfigIC.ICSelection = TIM_ICSELECTION_TRC;
  sConfigIC.ICPrescaler = TIM_ICPSC_DIV1;
  sConfigIC.ICFilter = 0;
 

[waclawek.jan]

> I get 1440 puls from timer 4->CNT register but captured2 value from tim5 callback function give 360 puls is it correct

I don't use Cube and am not going to decipher your code, but if you set encoder to increment on both edges of both signals (TIMx_SMCR.SMS=0b011), it "sees" four time more edges when the encoder is turned in one direction all the time, than the slave timer's counter, which counts only on one signal's rising edge.

JW

[goktug]

thank for your reply , my problem is both channels activated and both channels rising edge in TIM4 so in this scenario TIM4 counter is successfully measure 1440 puls (it means 100% resolution of encoder) but same time TIM5 captured callback just triggered 360 puls (I manually turn motor wheel one revolution)

but after read your reply , I set tim4 both channels and both edge and tim4 counter "TIM4->CNT value which doesn't seem to count up or down consistently."

the same issiue happened in here (https://community.st.com/s/question/0D50X00009XkdsT/tim4-in-encoder-mode-nucleo-f767zi)

but tim5 callback counter increased 720 puls in one revolution it's like joke !?

(by the way my setup board is stm32f407vgtx)

thanks.