HAL_ADC_ConvCpltCallback only called once

[nollstead]

I have a custom board with an STM32WB55CEU6 that I'm programming using the STM32CubeIDE.  I'm struggling with getting the ADC to work in DMA mode.  I can connect via SWD and the while loop runs fine but HAL_ADC_ConvCpltCallback is only triggered once (as confirmed by a breakpoint in that function).

• Continuous Conversion Mode = Enabled
• DMA Continuous Requests = Enabled
• Resolution is 8-bit.  What's connected is a joystick and I just need 0-255
• DMA set to Circular with data width set to Word

Here is the code.  Nearly all of this was auto-generated by STM32CubeIDE (I removed most of the comment blocks to make it easier to read) - all I really changed was adding in the HAL_ADC_ConvCpltCallback function, a variable to store the results, a call to HAL_ADC_Start_DMA and an LED toggle.  

Any help would be greatly appreciated.  I feel as if I have to be missing something simple but hours into it I can't find it.

 

/* Includes ------------------------------------------------------------------*/
#include "main.h"
#include "usb_device.h"


/* Private variables ---------------------------------------------------------*/
ADC_HandleTypeDef hadc1;
DMA_HandleTypeDef hdma_adc1;

RTC_HandleTypeDef hrtc;

/* USER CODE BEGIN PV */
uint32_t AD_RES_BUFFER[2];

/* USER CODE END PV */

/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
void PeriphCommonClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_DMA_Init(void);
static void MX_ADC1_Init(void);
static void MX_RTC_Init(void);

/* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 */
void HAL_ADC_ConvCpltCallback(ADC_HandleTypeDef* hadc) {

	// Continuous ADC conversion of Analog inputs is complete and stored in the data structure to be used later.
	uint32_t x = AD_RES_BUFFER[0];
	uint32_t y = AD_RES_BUFFER[1];
	uint8_t z = 1;
	x++;
	y++;
	z++;

}

/* USER CODE END 0 */

/**
 * @brief The application entry point.
 * @retval int
 */
int main(void)
{

 /* Reset of all peripherals, Initializes the Flash interface and the Systick. */
 HAL_Init();


 /* Configure the system clock */
 SystemClock_Config();

/* Configure the peripherals common clocks */
 PeriphCommonClock_Config();


 /* Initialize all configured peripherals */
 MX_GPIO_Init();
 MX_DMA_Init();
 MX_USB_Device_Init();
 MX_ADC1_Init();
 MX_RTC_Init();
 /* USER CODE BEGIN 2 */
 HAL_GPIO_WritePin(LED_GPIO_Port, LED_Pin, GPIO_PIN_SET);
 HAL_ADC_Start_DMA(&hadc1, AD_RES_BUFFER, 2);
 /* USER CODE END 2 */

 /* Infinite loop */
 /* USER CODE BEGIN WHILE */
 uint8_t x = 0;
 while (1)
 {
	 x++;
 }
}

/**
 * @brief System Clock Configuration
 * @retval None
 */
void SystemClock_Config(void)
{
 RCC_OscInitTypeDef RCC_OscInitStruct = {0};
 RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};

 /** Configure the main internal regulator output voltage
 */
 __HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE1);

 /** Initializes the RCC Oscillators according to the specified parameters
 * in the RCC_OscInitTypeDef structure.
 */
 RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI|RCC_OSCILLATORTYPE_LSI1
 |RCC_OSCILLATORTYPE_HSE;
 RCC_OscInitStruct.HSEState = RCC_HSE_ON;
 RCC_OscInitStruct.HSIState = RCC_HSI_ON;
 RCC_OscInitStruct.HSICalibrationValue = RCC_HSICALIBRATION_DEFAULT;
 RCC_OscInitStruct.LSIState = RCC_LSI_ON;
 RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
 RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
 RCC_OscInitStruct.PLL.PLLM = RCC_PLLM_DIV2;
 RCC_OscInitStruct.PLL.PLLN = 8;
 RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV2;
 RCC_OscInitStruct.PLL.PLLR = RCC_PLLR_DIV2;
 RCC_OscInitStruct.PLL.PLLQ = RCC_PLLQ_DIV2;
 if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
 {
 Error_Handler();
 }

 /** Configure the SYSCLKSource, HCLK, PCLK1 and PCLK2 clocks dividers
 */
 RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK4|RCC_CLOCKTYPE_HCLK2
 |RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
 |RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2;
 RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
 RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
 RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;
 RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;
 RCC_ClkInitStruct.AHBCLK2Divider = RCC_SYSCLK_DIV2;
 RCC_ClkInitStruct.AHBCLK4Divider = RCC_SYSCLK_DIV1;

 if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_3) != HAL_OK)
 {
 Error_Handler();
 }
}

/**
 * @brief Peripherals Common Clock Configuration
 * @retval None
 */
void PeriphCommonClock_Config(void)
{
 RCC_PeriphCLKInitTypeDef PeriphClkInitStruct = {0};

 /** Initializes the peripherals clock
 */
 PeriphClkInitStruct.PeriphClockSelection = RCC_PERIPHCLK_SMPS|RCC_PERIPHCLK_USB
 |RCC_PERIPHCLK_ADC;
 PeriphClkInitStruct.PLLSAI1.PLLN = 6;
 PeriphClkInitStruct.PLLSAI1.PLLP = RCC_PLLP_DIV2;
 PeriphClkInitStruct.PLLSAI1.PLLQ = RCC_PLLQ_DIV2;
 PeriphClkInitStruct.PLLSAI1.PLLR = RCC_PLLR_DIV2;
 PeriphClkInitStruct.PLLSAI1.PLLSAI1ClockOut = RCC_PLLSAI1_USBCLK|RCC_PLLSAI1_ADCCLK;
 PeriphClkInitStruct.UsbClockSelection = RCC_USBCLKSOURCE_PLLSAI1;
 PeriphClkInitStruct.AdcClockSelection = RCC_ADCCLKSOURCE_PLLSAI1;
 PeriphClkInitStruct.SmpsClockSelection = RCC_SMPSCLKSOURCE_HSI;
 PeriphClkInitStruct.SmpsDivSelection = RCC_SMPSCLKDIV_RANGE1;

 if (HAL_RCCEx_PeriphCLKConfig(&PeriphClkInitStruct) != HAL_OK)
 {
 Error_Handler();
 }
 /* USER CODE BEGIN Smps */

 /* USER CODE END Smps */
}

/**
 * @brief ADC1 Initialization Function
 * @PAram None
 * @retval None
 */
static void MX_ADC1_Init(void)
{


 ADC_ChannelConfTypeDef sConfig = {0};

 hadc1.Instance = ADC1;
 hadc1.Init.ClockPrescaler = ADC_CLOCK_ASYNC_DIV1;
 hadc1.Init.Resolution = ADC_RESOLUTION_8B;
 hadc1.Init.DataAlign = ADC_DATAALIGN_RIGHT;
 hadc1.Init.ScanConvMode = ADC_SCAN_ENABLE;
 hadc1.Init.EOCSelection = ADC_EOC_SINGLE_CONV;
 hadc1.Init.LowPowerAutoWait = DISABLE;
 hadc1.Init.ContinuousConvMode = ENABLE;
 hadc1.Init.NbrOfConversion = 2;
 hadc1.Init.DiscontinuousConvMode = DISABLE;
 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.OversamplingMode = DISABLE;
 if (HAL_ADC_Init(&hadc1) != HAL_OK)
 {
 Error_Handler();
 }

 /** Configure Regular Channel
 */
 sConfig.Channel = ADC_CHANNEL_15;
 sConfig.Rank = ADC_REGULAR_RANK_1;
 sConfig.SamplingTime = ADC_SAMPLETIME_2CYCLES_5;
 sConfig.SingleDiff = ADC_SINGLE_ENDED;
 sConfig.OffsetNumber = ADC_OFFSET_NONE;
 sConfig.Offset = 0;
 if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
 {
 Error_Handler();
 }

 /** Configure Regular Channel
 */
 sConfig.Channel = ADC_CHANNEL_16;
 sConfig.Rank = ADC_REGULAR_RANK_2;
 if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
 {
 Error_Handler();
 }

}

/**
 * @brief RTC Initialization Function
 * @PAram None
 * @retval None
 */
static void MX_RTC_Init(void)
{

 /** Initialize RTC Only
 */
 hrtc.Instance = RTC;
 hrtc.Init.HourFormat = RTC_HOURFORMAT_24;
 hrtc.Init.AsynchPrediv = 127;
 hrtc.Init.SynchPrediv = 255;
 hrtc.Init.OutPut = RTC_OUTPUT_DISABLE;
 hrtc.Init.OutPutPolarity = RTC_OUTPUT_POLARITY_HIGH;
 hrtc.Init.OutPutType = RTC_OUTPUT_TYPE_OPENDRAIN;
 hrtc.Init.OutPutRemap = RTC_OUTPUT_REMAP_NONE;
 if (HAL_RTC_Init(&hrtc) != HAL_OK)
 {
 Error_Handler();
 }

 /** Enable the WakeUp
 */
 if (HAL_RTCEx_SetWakeUpTimer(&hrtc, 0, RTC_WAKEUPCLOCK_RTCCLK_DIV16) != HAL_OK)
 {
 Error_Handler();
 }

}

/**
 * Enable DMA controller clock
 */
static void MX_DMA_Init(void)
{

 /* DMA controller clock enable */
 __HAL_RCC_DMAMUX1_CLK_ENABLE();
 __HAL_RCC_DMA1_CLK_ENABLE();

 /* DMA interrupt init */
 /* DMA1_Channel1_IRQn interrupt configuration */
 HAL_NVIC_SetPriority(DMA1_Channel1_IRQn, 0, 0);
 HAL_NVIC_EnableIRQ(DMA1_Channel1_IRQn);

}

/**
 * @brief GPIO Initialization Function
 * @PAram None
 * @retval None
 */
static void MX_GPIO_Init(void)
{
 GPIO_InitTypeDef GPIO_InitStruct = {0};
/* USER CODE BEGIN MX_GPIO_Init_1 */
/* USER CODE END MX_GPIO_Init_1 */

 /* GPIO Ports Clock Enable */
 __HAL_RCC_GPIOC_CLK_ENABLE();
 __HAL_RCC_GPIOH_CLK_ENABLE();
 __HAL_RCC_GPIOA_CLK_ENABLE();
 __HAL_RCC_GPIOB_CLK_ENABLE();

 /*Configure GPIO pin Output Level */
 HAL_GPIO_WritePin(LED_GPIO_Port, LED_Pin, GPIO_PIN_RESET);

 /*Configure GPIO pin : Button4_BOOT0_Pin */
 GPIO_InitStruct.Pin = Button4_BOOT0_Pin;
 GPIO_InitStruct.Mode = GPIO_MODE_INPUT;
 GPIO_InitStruct.Pull = GPIO_NOPULL;
 HAL_GPIO_Init(Button4_BOOT0_GPIO_Port, &GPIO_InitStruct);

 /*Configure GPIO pin : LED_Pin */
 GPIO_InitStruct.Pin = LED_Pin;
 GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
 GPIO_InitStruct.Pull = GPIO_NOPULL;
 GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
 HAL_GPIO_Init(LED_GPIO_Port, &GPIO_InitStruct);

}


/**
 * @brief This function is executed in case of error occurrence.
 * @retval None
 */
void Error_Handler(void)
{
 /* USER CODE BEGIN Error_Handler_Debug */
 /* User can add his own implementation to report the HAL error return state */
 __disable_irq();
 while (1)
 {
 }
 /* USER CODE END Error_Handler_Debug */
}

#ifdef USE_FULL_ASSERT
/**
 * @brief Reports the name of the source file and the source line number
 * where the assert_param error has occurred.
 * @PAram file: pointer to the source file name
 * @PAram line: assert_param error line source number
 * @retval None
 */
void assert_failed(uint8_t *file, uint32_t line)
{
 /* USER CODE BEGIN 6 */
 /* User can add his own implementation to report the file name and line number,
 ex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */
 /* USER CODE END 6 */
}
#endif /* USE_FULL_ASSERT */

 

 

[TDK]

> DMA set to Circular with data width set to Word

For 8 bit ADC values, you should use byte width, not word width.

> sConfig.SamplingTime = ADC_SAMPLETIME_2CYCLES_5

May want to increase that, at least during debugging. You may be stressing the DMA bandwidth available at that rate.

Calling DMA for 2 values is pretty inefficient, especially if it's continuously converting. It will call the half-complete callback on the first value and the full-complete callback on the second. That's 1 callback per conversion. Not going to be able to keep up with callbacks at that rate, especially not with the lowest sampling time.

[nollstead]

Thank you for the reply.  My full application will have 7 ADC conversions and send those out via BLE.  Instead of troubleshooting a full app I put together this simple one (with just two analog conversions) to simply things and eliminate other areas of possible conflict.  

I changed to byte - something I was planning anyway, though one of my analog values (voltage monitor) may force me to half-word - and a sampling time of 6.5 but, while probably more efficient (and appreciated) I still have the same problem with the callback only getting fired once.  

[Karl Yamashita]

You've set the ADC to do conversion on software start. You should instead set the ADC conversion to trigger off a timer at an interval. When the conversion is done then HAL_ADC_ConvCpltCallback will be called and then repeat

 

 

[nollstead]

Ooh I like that Idea. I had planned to look into timers, and wondered if i needed them here) but hadn't gotten there yet - then I could configure a prescaler to control how often it runs, etc.

 

How would I implement the timer part though?  I see "Capture Compare 1 event", Capture Compare 2 event", "Trigger out event", etc.  Any push in the right direction (or resource to read) would be helpful.

 

Forgive the newbie questions as I'm a long-time Arduino developer who is just getting into STM32