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When I setup the RANK for the ADC I want to read TemperatureSensor, VRef, IN0, IN1. But the order appears IN1, TemperatureSensor, Vref, IN0

KiptonM
Lead

‎2022-06-07 08:59 AM

In the MX program I set up the rank. to scan 4 values.

TemperatureSensor, VRefint, IN0, IN1.

I Initially saw this in DMA mode, But see it also happens in Discontinuous Mode.

0693W00000NrLM9QAN.pngBut when read the order is off by 1 position.

It looks like it is reading IN1, TemperatureSensor, VRefint, IN0,

Here is the relevant code.

/* MCU Configuration--------------------------------------------------------*/
 
  /* Reset of all peripherals, Initializes the Flash interface and the Systick. */
  HAL_Init();
 
  /* USER CODE BEGIN Init */
 
  /* USER CODE END Init */
 
  /* Configure the system clock */
  SystemClock_Config();
 
  /* USER CODE BEGIN SysInit */
 
  /* USER CODE END SysInit */
 
  /* Initialize all configured peripherals */
  MX_GPIO_Init();
  MX_DMA_Init();
  MX_USART1_UART_Init();
  MX_USART2_UART_Init();
  MX_I2C1_Init();
  MX_TIM2_Init();
  MX_TIM3_Init();
  MX_ADC1_Init();
 
  /* Initialize interrupts */
  MX_NVIC_Init();
  /* USER CODE BEGIN 2 */
 
  //ADC_init();
 
  if (HAL_ADCEx_Calibration_Start(&hadc1) != HAL_OK)
  {
	  print_debug_str("Did not calibrate right!");
  }
 
  //ADC_DMA_Setup();
 
  HAL_Delay(100); // Make sure print is done.
 
  {
	  char buf[100];
	  uint16_t i;
	  uint16_t refv;
	  uint16_t temp;
	  uint16_t adc_data[4];
	  for (i=0;i<50;i++)
	  {
 
		  adc_data[0] = 0xFFFF;
		  adc_data[0] = 0xFFFF;
		  adc_data[0] = 0xFFFF;
		  adc_data[0] = 0xFFFF;
		  ADC1->IER = 0; // make sure this is clear
 
		  // This should be Temperature
		  ADC1->ISR |= 2;  // Clear EOC Flag
		  HAL_ADC_Start(&hadc1);
		  while ((ADC1->ISR & 2) ==  0);
		  adc_data[0] = ADC1->DR;
		  ADC1->ISR |= 2;
 
		  // This should be vref
		  HAL_ADC_Start(&hadc1);
		  while ((ADC1->ISR & 2) ==  0) ;
		  adc_data[1] = ADC1->DR;
		  ADC1->ISR |= 2;
 
		  // This should be a voltage -- Not connected expect 0
		  HAL_ADC_Start(&hadc1);
		  while ((ADC1->ISR & 2) ==  0) ;
		  adc_data[2] = ADC1->DR;
		  ADC1->ISR |= 2;
 
		  // This should be a current -- Not connected expect 0
		  HAL_ADC_Start(&hadc1);
		  while ((ADC1->ISR & 2) ==  0) ;
		  adc_data[3] = ADC1->DR;
		  ADC1->ISR |= 2;
 
		  refv = __HAL_ADC_CALC_VREFANALOG_VOLTAGE(adc_data[2],ADC_RESOLUTION_12B);
		  temp = __HAL_ADC_CALC_TEMPERATURE(refv,adc_data[1],ADC_RESOLUTION_12B);
 
 
		  sprintf(buf,"%4u  ADC Discontinuous readings: %04X %04X %04X %04X TempC: %u, Vref mV: %u\r\n",i, adc_data[0],adc_data[1],adc_data[2],adc_data[3], temp, refv);
		  print_debug_str(buf);
 
		  HAL_Delay(100); // make sure print has time to finish.
	  } // for
  }
 
  while(1); // Stop here while debugging ADC

Looking at the printout it is:

   0  ADC Discontinuous readings: 0020 039D 05D7 0001 TempC: 27, Vref mV: 3331
   1  ADC Discontinuous readings: 0001 039F 05D6 0002 TempC: 27, Vref mV: 3333
   2  ADC Discontinuous readings: 0000 03A3 05E4 0000 TempC: 26, Vref mV: 3302
   3  ADC Discontinuous readings: 0001 03A5 05E4 0000 TempC: 26, Vref mV: 3302
   4  ADC Discontinuous readings: 0002 03A5 05E3 0001 TempC: 27, Vref mV: 3304
   5  ADC Discontinuous readings: 0001 03A5 05E2 0001 TempC: 27, Vref mV: 3306
   6  ADC Discontinuous readings: 0001 03A5 05E4 0001 TempC: 26, Vref mV: 3302
   7  ADC Discontinuous readings: 0001 03A4 05E2 0001 TempC: 27, Vref mV: 3306
   8  ADC Discontinuous readings: 0002 03A6 05E3 0000 TempC: 27, Vref mV: 3304
   9  ADC Discontinuous readings: 0002 03A5 05E2 0000 TempC: 27, Vref mV: 3306
  10  ADC Discontinuous readings: 0001 03A7 05E4 0001 TempC: 27, Vref mV: 3302
  11  ADC Discontinuous readings: 0002 03A5 05E4 0001 TempC: 26, Vref mV: 3302
  12  ADC Discontinuous readings: 0002 039F 05D8 0001 TempC: 27, Vref mV: 3328
  13  ADC Discontinuous readings: 0002 03A3 05DF 0001 TempC: 27, Vref mV: 3313
  14  ADC Discontinuous readings: 0001 03A6 05E3 0001 TempC: 27, Vref mV: 3304
  15  ADC Discontinuous readings: 0002 03A6 05E3 0000 TempC: 27, Vref mV: 3304
  16  ADC Discontinuous readings: 0001 03A5 05E4 0001 TempC: 26, Vref mV: 3302
  17  ADC Discontinuous readings: 0001 03A6 05E3 0000 TempC: 27, Vref mV: 3304
  18  ADC Discontinuous readings: 0002 03A5 05E4 0000 TempC: 26, Vref mV: 3302
  19  ADC Discontinuous readings: 0002 03A5 05E3 0000 TempC: 27, Vref mV: 3304
  20  ADC Discontinuous readings: 0001 03A5 05E3 0001 TempC: 27, Vref mV: 3304
  21  ADC Discontinuous readings: 0002 03A6 05E4 0002 TempC: 27, Vref mV: 3302
  22  ADC Discontinuous readings: 0002 03A6 05E4 0001 TempC: 27, Vref mV: 3302
  23  ADC Discontinuous readings: 0002 03A3 05DF 0000 TempC: 27, Vref mV: 3313
  24  ADC Discontinuous readings: 0001 03A5 05E4 0001 TempC: 26, Vref mV: 3302
  25  ADC Discontinuous readings: 0002 03A6 05E2 0000 TempC: 27, Vref mV: 3306
  26  ADC Discontinuous readings: 0003 03A6 05E3 0001 TempC: 27, Vref mV: 3304
  27  ADC Discontinuous readings: 0001 03A5 05E4 0001 TempC: 26, Vref mV: 3302
  28  ADC Discontinuous readings: 0002 03A7 05E3 0001 TempC: 27, Vref mV: 3304
  29  ADC Discontinuous readings: 0002 03A6 05E2 0001 TempC: 27, Vref mV: 3306
  30  ADC Discontinuous readings: 0002 03A7 05E3 0001 TempC: 27, Vref mV: 3304
  31  ADC Discontinuous readings: 0002 03A6 05DF 0000 TempC: 28, Vref mV: 3313
  32  ADC Discontinuous readings: 0002 03A5 05E2 0002 TempC: 27, Vref mV: 3306
  33  ADC Discontinuous readings: 0001 03A5 05E3 0001 TempC: 27, Vref mV: 3304
  34  ADC Discontinuous readings: 0002 03A5 05E3 0001 TempC: 27, Vref mV: 3304
  35  ADC Discontinuous readings: 0002 03A0 05DA 0000 TempC: 27, Vref mV: 3324
  36  ADC Discontinuous readings: 0001 03A6 05E4 0001 TempC: 27, Vref mV: 3302
  37  ADC Discontinuous readings: 0001 03A6 05E2 0001 TempC: 27, Vref mV: 3306
  38  ADC Discontinuous readings: 0001 03A5 05E5 0002 TempC: 26, Vref mV: 3300
  39  ADC Discontinuous readings: 0001 03A7 05E4 0001 TempC: 27, Vref mV: 3302
  40  ADC Discontinuous readings: 0002 03A6 05E2 0001 TempC: 27, Vref mV: 3306
  41  ADC Discontinuous readings: 0001 03A6 05E4 0000 TempC: 27, Vref mV: 3302
  42  ADC Discontinuous readings: 0002 03A7 05E3 0000 TempC: 27, Vref mV: 3304
  43  ADC Discontinuous readings: 0001 03A7 05E3 0001 TempC: 27, Vref mV: 3304
  44  ADC Discontinuous readings: 0001 03A6 05E3 0000 TempC: 27, Vref mV: 3304
  45  ADC Discontinuous readings: 0002 03A6 05E4 0001 TempC: 27, Vref mV: 3302
  46  ADC Discontinuous readings: 0002 03A5 05E4 0000 TempC: 26, Vref mV: 3302
  47  ADC Discontinuous readings: 0001 03A6 05E5 0000 TempC: 27, Vref mV: 3300
  48  ADC Discontinuous readings: 0001 03A1 05DB 0000 TempC: 27, Vref mV: 3322
  49  ADC Discontinuous readings: 0001 03A6 05E3 0001 TempC: 27, Vref mV: 3304

For a sanity check I converted the second one (adc_data[1]) to a temperature, and the third one )adc_data[2] to a voltage in mV, and they confirm they are in the wrong place.

The generated code looks right.

/**
  * @brief ADC1 Initialization Function
  * @param None
  * @retval None
  */
static void MX_ADC1_Init(void)
{
 
  /* USER CODE BEGIN ADC1_Init 0 */
 
  /* USER CODE END ADC1_Init 0 */
 
  ADC_ChannelConfTypeDef sConfig = {0};
 
  /* USER CODE BEGIN ADC1_Init 1 */
 
  /* USER CODE END ADC1_Init 1 */
 
  /** Configure the global features of the ADC (Clock, Resolution, Data Alignment and number of conversion)
  */
  hadc1.Instance = ADC1;
  hadc1.Init.ClockPrescaler = ADC_CLOCK_SYNC_PCLK_DIV2;
  hadc1.Init.Resolution = ADC_RESOLUTION_12B;
  hadc1.Init.DataAlign = ADC_DATAALIGN_RIGHT;
  hadc1.Init.ScanConvMode = ADC_SCAN_ENABLE;
  hadc1.Init.EOCSelection = ADC_EOC_SEQ_CONV;
  hadc1.Init.LowPowerAutoWait = DISABLE;
  hadc1.Init.LowPowerAutoPowerOff = DISABLE;
  hadc1.Init.ContinuousConvMode = DISABLE;
  hadc1.Init.NbrOfConversion = 4;
  hadc1.Init.DiscontinuousConvMode = ENABLE;
  hadc1.Init.ExternalTrigConv = ADC_SOFTWARE_START;
  hadc1.Init.ExternalTrigConvEdge = ADC_EXTERNALTRIGCONVEDGE_NONE;
  hadc1.Init.DMAContinuousRequests = DISABLE;
  hadc1.Init.Overrun = ADC_OVR_DATA_PRESERVED;
  hadc1.Init.SamplingTimeCommon1 = ADC_SAMPLETIME_39CYCLES_5;
  hadc1.Init.SamplingTimeCommon2 = ADC_SAMPLETIME_160CYCLES_5;
  hadc1.Init.OversamplingMode = DISABLE;
  hadc1.Init.TriggerFrequencyMode = ADC_TRIGGER_FREQ_HIGH;
  if (HAL_ADC_Init(&hadc1) != HAL_OK)
  {
    Error_Handler();
  }
 
  /** Configure Regular Channel
  */
  sConfig.Channel = ADC_CHANNEL_TEMPSENSOR;
  sConfig.Rank = ADC_REGULAR_RANK_1;
  sConfig.SamplingTime = ADC_SAMPLINGTIME_COMMON_2;
  if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
  {
    Error_Handler();
  }
 
  /** Configure Regular Channel
  */
  sConfig.Channel = ADC_CHANNEL_VREFINT;
  sConfig.Rank = ADC_REGULAR_RANK_2;
  if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
  {
    Error_Handler();
  }
 
  /** Configure Regular Channel
  */
  sConfig.Channel = ADC_CHANNEL_0;
  sConfig.Rank = ADC_REGULAR_RANK_3;
  sConfig.SamplingTime = ADC_SAMPLINGTIME_COMMON_1;
  if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
  {
    Error_Handler();
  }
 
  /** Configure Regular Channel
  */
  sConfig.Channel = ADC_CHANNEL_1;
  sConfig.Rank = ADC_REGULAR_RANK_4;
  if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
  {
    Error_Handler();
  }
  /* USER CODE BEGIN ADC1_Init 2 */
 
  /* USER CODE END ADC1_Init 2 */
 
}

Why is the order wrong?

How do I fix it?

Thanks, in advance.

Labels:
EncoderBoardRevA.ioc
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3 REPLIES 3
KiptonM
Lead

‎2022-06-07 01:04 PM

I did not change anything in the MX program. I did change the the oversample to 8 in the ADC_CFGR2 register and set OVSE to enable it.

Now the order is correct!

In this line are the values as read from the ADC_DR (x8) Temp, Vref, AN0, AN1

ADC Discontinuous 8 readings: 1D37 2F28 0007 0020 FFFF FFFF FFFF FFFF

Here I shifted right 3 positions each of the values. And converted the first to Temperature in C, Temperature in F * 10, and second The Reference Voltage in mV. They all look good and are in the right position.

ADC Discontinuous readings: 03A6 05E5 0000 0004 TempC:  27, TempF*10: 806, Vref mV: 3300

I tried to run the routine 10 times but only got values the first time. I am going to hunt that down next.

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HCui
Associate II

‎2022-06-10 05:11 PM

I also ran into this bug recently. My solution is adding a delay (1ms) after stopping the DMA. It is confusing.

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Javier1
Principal

‎2022-06-13 12:34 AM

Same/similar thing happened to me, i wasnt giving the DMA enough time to fill the ADC readings buffer, i fixed it by speeding up the ADC triggers

we dont need to firmware by ourselves, lets talk
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