STM32H755 dual ADC DMA timer trigger

[mosamasa]

Hi,

I'm using STM32H755ZI-Q Nucleo board and I'm trying to use TIM2 to trigger Dual ADC conversion. M7 core is running FREERTOS and M4 is bare metal. ADC is controlled by M4 core. DMA is used to transfer data to M7 and then M7 is using ethernet to transfer data further. Sampling rate of my ADC is 1.92MSPS (12bit). I'm tring to use TIM2 to trigger ADC. This should happen with rate of 60Hz. Every 16.67ms (60Hz), I would like to collect 2x2048 samples.

It seems that I'm not getting configuration of ADC correct, since I'm actually getting one sample pair with 60Hz rate.  I'm not sure if configuration of ADC or DMA is incorrect? HAL_ADC_ConvCpltCallback() is firing at rate ~0.5Hz.

[mosamasa]

Small correction. I'm currently collecting only 2x128 samples (not 2x2048), since it takes long time to get 2048 samples with current rate.

[mosamasa]

I have had some progress now. One problem was DMA. I had data width half word instead of word. Dual regular simultaneous mode only is not probably right choice for me?

I tested independent mode and it seems to work somehow.

I have two problems:

1. It seems that sample rate is half of expected. I would like to have 1.92MSPS per ADC. It seems that I'm getting only 960kSPS per ADC. I'm not sure why I'm losing 50% of samples.

2. I don't get TIM2 trigger work as I hope. I need to use software trigger to start ADC. This is not big deal, but it would be great to find root cause.

/* USER CODE BEGIN Header */
/**
 ******************************************************************************
 * @file : main.c
 * @brief : Main program body
 ******************************************************************************
 * @attention
 *
 * Copyright (c) 2025 STMicroelectronics.
 * All rights reserved.
 *
 * This software is licensed under terms that can be found in the LICENSE file
 * in the root directory of this software component.
 * If no LICENSE file comes with this software, it is provided AS-IS.
 *
 ******************************************************************************
 */
/* USER CODE END Header */
/* Includes ------------------------------------------------------------------*/
#include "main.h"

/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
#include "../../../Common/Inc/shared_adc.h"
/* USER CODE END Includes */

/* Private typedef -----------------------------------------------------------*/
/* USER CODE BEGIN PTD */

/* USER CODE END PTD */

/* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD */

#ifndef HSEM_ID_0
#define HSEM_ID_0 (0U) /* HW semaphore 0*/
#endif

/* USER CODE END PD */

/* Private macro -------------------------------------------------------------*/
/* USER CODE BEGIN PM */

/* USER CODE END PM */

/* Private variables ---------------------------------------------------------*/
ADC_HandleTypeDef hadc1;
ADC_HandleTypeDef hadc2;
DMA_HandleTypeDef hdma_adc1;
DMA_HandleTypeDef hdma_adc2;

TIM_HandleTypeDef htim2;

UART_HandleTypeDef huart3;

/* USER CODE BEGIN PV */
extern ADC_HandleTypeDef hadc1;
/* USER CODE END PV */

/* Private function prototypes -----------------------------------------------*/
static void MX_GPIO_Init(void);
static void MX_DMA_Init(void);
static void MX_TIM2_Init(void);
static void MX_ADC1_Init(void);
static void MX_ADC2_Init(void);
/* USER CODE BEGIN PFP */

/* USER CODE END PFP */

/* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 */
void HAL_ADC_ConvCpltCallback(ADC_HandleTypeDef* hadc) {
 if (hadc == &hadc1) {
 // Mark buffer as ready to be sent
 SHARED_ADC_DATA->buffer_counter++;

 // Toggle debug pin to monitor DMA completion
 // HAL_GPIO_TogglePin(DEBUG_OUTPUT_GPIO_Port, DEBUG_OUTPUT_Pin);
 // :white_heavy_check_mark: Re-arm ADC1
 // HAL_ADC_Start_DMA(&hadc1, (uint32_t*)SHARED_ADC_DATA->adc1_buffer, ADC_BUFFER_LENGTH);

 // :white_heavy_check_mark: Re-arm ADC2
 // HAL_ADC_Start_DMA(&hadc2, (uint32_t*)SHARED_ADC_DATA->adc2_buffer, ADC_BUFFER_LENGTH);
 // Do not restart ADC – timer will trigger it at 60 Hz
 }

}



void HAL_TIM_PeriodElapsedCallback(TIM_HandleTypeDef *htim)
{
 if (htim->Instance == TIM2) {
 HAL_GPIO_TogglePin(DEBUG_OUTPUT_GPIO_Port, DEBUG_OUTPUT_Pin);

 HAL_ADC_Start_DMA(
 &hadc1,
 (uint32_t*)SHARED_ADC_DATA->adc1_buffer,
 ADC_BUFFER_LENGTH
 );

 HAL_ADC_Start_DMA(
 &hadc2,
 (uint32_t*)SHARED_ADC_DATA->adc2_buffer,
 ADC_BUFFER_LENGTH
 );
 }
}




/* USER CODE END 0 */

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

 /* USER CODE BEGIN 1 */

 /* USER CODE END 1 */

/* USER CODE BEGIN Boot_Mode_Sequence_1 */


	 /*HW semaphore Clock enable*/
	 __HAL_RCC_HSEM_CLK_ENABLE();
	// /* Activate HSEM notification for Cortex-M4*/
	 HAL_HSEM_ActivateNotification(__HAL_HSEM_SEMID_TO_MASK(HSEM_ID_0));
	// /*
	// Domain D2 goes to STOP mode (Cortex-M4 in deep-sleep) waiting for Cortex-M7 to
	// perform system initialization (system clock config, external memory configuration.. )
	// */
	 HAL_PWREx_ClearPendingEvent();
	 HAL_PWREx_EnterSTOPMode(PWR_MAINREGULATOR_ON, PWR_STOPENTRY_WFE, PWR_D2_DOMAIN);
	// /* Clear HSEM flag */
	 __HAL_HSEM_CLEAR_FLAG(__HAL_HSEM_SEMID_TO_MASK(HSEM_ID_0));

/* USER CODE END Boot_Mode_Sequence_1 */
 /* MCU Configuration--------------------------------------------------------*/

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

 /* USER CODE BEGIN Init */

 /* USER CODE END Init */

 /* USER CODE BEGIN SysInit */

 /* USER CODE END SysInit */

 /* Initialize all configured peripherals */
 MX_GPIO_Init();
 MX_DMA_Init();
 MX_TIM2_Init();
 MX_ADC1_Init();
 MX_ADC2_Init();
 /* USER CODE BEGIN 2 */





 //HAL_ADCEx_MultiModeStart_DMA(&hadc1,
 // (uint32_t*)SHARED_ADC_DATA->adc_buffer,
 // ADC_BUFFER_LENGTH);
/* HAL_ADC_Start(&hadc2);

 HAL_StatusTypeDef result = HAL_ADCEx_MultiModeStart_DMA(
 &hadc1,
 (uint32_t*)SHARED_ADC_DATA->adc_buffer,
 ADC_BUFFER_LENGTH
 );

 if (result != HAL_OK) {
 while (1) {
 HAL_GPIO_TogglePin(YELLOW_LED_GPIO_Port, YELLOW_LED_Pin);
 HAL_Delay(100);
 }
 }
*/


 HAL_ADC_Start_DMA(
 &hadc1,
 (uint32_t*)SHARED_ADC_DATA->adc1_buffer,
 ADC_BUFFER_LENGTH
 );

 HAL_ADC_Start_DMA(
 &hadc2,
 (uint32_t*)SHARED_ADC_DATA->adc2_buffer,
 ADC_BUFFER_LENGTH
 );

 // :white_heavy_check_mark: Start TIM2 after ADC DMA is ready
 //HAL_NVIC_SetPriority(TIM2_IRQn, 1, 0);
 //HAL_NVIC_EnableIRQ(TIM2_IRQn);
 HAL_TIM_Base_Start_IT(&htim2);
 //HAL_TIM_Base_Start(&htim2);

 //HAL_ADC_Start_DMA(&hadc1, (uint32_t*)SHARED_ADC_DATA->adc_buffer, ADC_BUFFER_LENGTH);


 //HAL_ADC_ConvCpltCallback(&hadc1); // simulate callback
 /* USER CODE END 2 */

 /* Infinite loop */
 /* USER CODE BEGIN WHILE */
 while (1)
 {
 /* USER CODE END WHILE */

 /* USER CODE BEGIN 3 */
	 HAL_GPIO_TogglePin(YELLOW_LED_GPIO_Port, YELLOW_LED_Pin); // :white_heavy_check_mark: Toggle LED (Check your Nucleo LED pin)

 HAL_Delay(1000); // fast blink = ADC start failure
 /* HAL_ADC_Start(&hadc2);

 HAL_StatusTypeDef result = HAL_ADCEx_MultiModeStart_DMA(
 &hadc1,
 (uint32_t*)SHARED_ADC_DATA->adc_buffer,
 ADC_BUFFER_LENGTH
 );
*/
 }
 /* USER CODE END 3 */
}

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

 /** Initializes the peripherals clock
 */
 PeriphClkInitStruct.PeriphClockSelection = RCC_PERIPHCLK_ADC;
 PeriphClkInitStruct.PLL2.PLL2M = 8;
 PeriphClkInitStruct.PLL2.PLL2N = 384;
 PeriphClkInitStruct.PLL2.PLL2P = 25;
 PeriphClkInitStruct.PLL2.PLL2Q = 2;
 PeriphClkInitStruct.PLL2.PLL2R = 2;
 PeriphClkInitStruct.PLL2.PLL2RGE = RCC_PLL2VCIRANGE_0;
 PeriphClkInitStruct.PLL2.PLL2VCOSEL = RCC_PLL2VCOWIDE;
 PeriphClkInitStruct.PLL2.PLL2FRACN = 0;
 PeriphClkInitStruct.AdcClockSelection = RCC_ADCCLKSOURCE_PLL2;
 if (HAL_RCCEx_PeriphCLKConfig(&PeriphClkInitStruct) != HAL_OK)
 {
 Error_Handler();
 }
}

/**
 * @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_MultiModeTypeDef multimode = {0};
 ADC_ChannelConfTypeDef sConfig = {0};

 /* USER CODE BEGIN ADC1_Init 1 */

 /* USER CODE END ADC1_Init 1 */

 /** Common config
 */
 hadc1.Instance = ADC1;
 hadc1.Init.ClockPrescaler = ADC_CLOCK_ASYNC_DIV1;
 hadc1.Init.Resolution = ADC_RESOLUTION_12B;
 hadc1.Init.ScanConvMode = ADC_SCAN_DISABLE;
 hadc1.Init.EOCSelection = ADC_EOC_SEQ_CONV;
 hadc1.Init.LowPowerAutoWait = DISABLE;
 hadc1.Init.ContinuousConvMode = ENABLE;
 hadc1.Init.NbrOfConversion = 1;
 hadc1.Init.DiscontinuousConvMode = DISABLE;
 hadc1.Init.NbrOfDiscConversion = 1;
 hadc1.Init.ExternalTrigConv = ADC_SOFTWARE_START;
 hadc1.Init.ExternalTrigConvEdge = ADC_EXTERNALTRIGCONVEDGE_NONE;
 hadc1.Init.ConversionDataManagement = ADC_CONVERSIONDATA_DMA_ONESHOT;
 hadc1.Init.Overrun = ADC_OVR_DATA_PRESERVED;
 hadc1.Init.LeftBitShift = ADC_LEFTBITSHIFT_NONE;
 hadc1.Init.OversamplingMode = DISABLE;
 hadc1.Init.Oversampling.Ratio = 1;
 if (HAL_ADC_Init(&hadc1) != HAL_OK)
 {
 Error_Handler();
 }

 /** Configure the ADC multi-mode
 */
 multimode.Mode = ADC_MODE_INDEPENDENT;
 if (HAL_ADCEx_MultiModeConfigChannel(&hadc1, &multimode) != HAL_OK)
 {
 Error_Handler();
 }

 /** Configure Regular Channel
 */
 sConfig.Channel = ADC_CHANNEL_2;
 sConfig.Rank = ADC_REGULAR_RANK_1;
 sConfig.SamplingTime = ADC_SAMPLETIME_1CYCLE_5;
 sConfig.SingleDiff = ADC_SINGLE_ENDED;
 sConfig.OffsetNumber = ADC_OFFSET_NONE;
 sConfig.Offset = 0;
 if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
 {
 Error_Handler();
 }
 /* USER CODE BEGIN ADC1_Init 2 */
 //__HAL_LINKDMA(&hadc1, DMA_Handle, hdma_adc1);
 /* USER CODE END ADC1_Init 2 */

}

/**
 * @brief ADC2 Initialization Function
 * @PAram None
 * @retval None
 */
static void MX_ADC2_Init(void)
{

 /* USER CODE BEGIN ADC2_Init 0 */

 /* USER CODE END ADC2_Init 0 */

 ADC_ChannelConfTypeDef sConfig = {0};

 /* USER CODE BEGIN ADC2_Init 1 */

 /* USER CODE END ADC2_Init 1 */

 /** Common config
 */
 hadc2.Instance = ADC2;
 hadc2.Init.ClockPrescaler = ADC_CLOCK_ASYNC_DIV1;
 hadc2.Init.Resolution = ADC_RESOLUTION_12B;
 hadc2.Init.ScanConvMode = ADC_SCAN_DISABLE;
 hadc2.Init.EOCSelection = ADC_EOC_SEQ_CONV;
 hadc2.Init.LowPowerAutoWait = DISABLE;
 hadc2.Init.ContinuousConvMode = ENABLE;
 hadc2.Init.NbrOfConversion = 1;
 hadc2.Init.DiscontinuousConvMode = DISABLE;
 hadc2.Init.ExternalTrigConv = ADC_SOFTWARE_START;
 hadc2.Init.ExternalTrigConvEdge = ADC_EXTERNALTRIGCONVEDGE_NONE;
 hadc2.Init.ConversionDataManagement = ADC_CONVERSIONDATA_DMA_ONESHOT;
 hadc2.Init.Overrun = ADC_OVR_DATA_PRESERVED;
 hadc2.Init.LeftBitShift = ADC_LEFTBITSHIFT_NONE;
 hadc2.Init.OversamplingMode = DISABLE;
 hadc2.Init.Oversampling.Ratio = 1;
 if (HAL_ADC_Init(&hadc2) != HAL_OK)
 {
 Error_Handler();
 }

 /** Configure Regular Channel
 */
 sConfig.Channel = ADC_CHANNEL_15;
 sConfig.Rank = ADC_REGULAR_RANK_1;
 sConfig.SamplingTime = ADC_SAMPLETIME_1CYCLE_5;
 sConfig.SingleDiff = ADC_SINGLE_ENDED;
 sConfig.OffsetNumber = ADC_OFFSET_NONE;
 sConfig.Offset = 0;
 sConfig.OffsetSignedSaturation = DISABLE;
 if (HAL_ADC_ConfigChannel(&hadc2, &sConfig) != HAL_OK)
 {
 Error_Handler();
 }
 /* USER CODE BEGIN ADC2_Init 2 */

 /* USER CODE END ADC2_Init 2 */

}

/**
 * @brief TIM2 Initialization Function
 * @PAram None
 * @retval None
 */
static void MX_TIM2_Init(void)
{

 /* USER CODE BEGIN TIM2_Init 0 */

 /* USER CODE END TIM2_Init 0 */

 TIM_ClockConfigTypeDef sClockSourceConfig = {0};
 TIM_MasterConfigTypeDef sMasterConfig = {0};

 /* USER CODE BEGIN TIM2_Init 1 */

 /* USER CODE END TIM2_Init 1 */
 htim2.Instance = TIM2;
 htim2.Init.Prescaler = 200-1;
 htim2.Init.CounterMode = TIM_COUNTERMODE_UP;
 htim2.Init.Period = 16666;
 htim2.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;
 htim2.Init.AutoReloadPreload = TIM_AUTORELOAD_PRELOAD_ENABLE;
 if (HAL_TIM_Base_Init(&htim2) != HAL_OK)
 {
 Error_Handler();
 }
 sClockSourceConfig.ClockSource = TIM_CLOCKSOURCE_INTERNAL;
 if (HAL_TIM_ConfigClockSource(&htim2, &sClockSourceConfig) != HAL_OK)
 {
 Error_Handler();
 }
 sMasterConfig.MasterOutputTrigger = TIM_TRGO_UPDATE;
 sMasterConfig.MasterSlaveMode = TIM_MASTERSLAVEMODE_ENABLE;
 if (HAL_TIMEx_MasterConfigSynchronization(&htim2, &sMasterConfig) != HAL_OK)
 {
 Error_Handler();
 }
 /* USER CODE BEGIN TIM2_Init 2 */

 /* USER CODE END TIM2_Init 2 */

}

/**
 * @brief USART3 Initialization Function
 * @PAram None
 * @retval None
 */
void MX_USART3_UART_Init(void)
{

 /* USER CODE BEGIN USART3_Init 0 */

 /* USER CODE END USART3_Init 0 */

 /* USER CODE BEGIN USART3_Init 1 */

 /* USER CODE END USART3_Init 1 */
 huart3.Instance = USART3;
 huart3.Init.BaudRate = 115200;
 huart3.Init.WordLength = UART_WORDLENGTH_8B;
 huart3.Init.StopBits = UART_STOPBITS_1;
 huart3.Init.Parity = UART_PARITY_NONE;
 huart3.Init.Mode = UART_MODE_TX_RX;
 huart3.Init.HwFlowCtl = UART_HWCONTROL_NONE;
 huart3.Init.OverSampling = UART_OVERSAMPLING_16;
 huart3.Init.OneBitSampling = UART_ONE_BIT_SAMPLE_DISABLE;
 huart3.Init.ClockPrescaler = UART_PRESCALER_DIV1;
 huart3.AdvancedInit.AdvFeatureInit = UART_ADVFEATURE_NO_INIT;
 if (HAL_UART_Init(&huart3) != HAL_OK)
 {
 Error_Handler();
 }
 if (HAL_UARTEx_SetTxFifoThreshold(&huart3, UART_TXFIFO_THRESHOLD_1_8) != HAL_OK)
 {
 Error_Handler();
 }
 if (HAL_UARTEx_SetRxFifoThreshold(&huart3, UART_RXFIFO_THRESHOLD_1_8) != HAL_OK)
 {
 Error_Handler();
 }
 if (HAL_UARTEx_DisableFifoMode(&huart3) != HAL_OK)
 {
 Error_Handler();
 }
 /* USER CODE BEGIN USART3_Init 2 */

 /* USER CODE END USART3_Init 2 */

}

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

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

 /* DMA interrupt init */
 /* DMA1_Stream0_IRQn interrupt configuration */
 HAL_NVIC_SetPriority(DMA1_Stream0_IRQn, 0, 0);
 HAL_NVIC_EnableIRQ(DMA1_Stream0_IRQn);
 /* DMA1_Stream1_IRQn interrupt configuration */
 HAL_NVIC_SetPriority(DMA1_Stream1_IRQn, 0, 0);
 HAL_NVIC_EnableIRQ(DMA1_Stream1_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_GPIOA_CLK_ENABLE();
 __HAL_RCC_GPIOF_CLK_ENABLE();
 __HAL_RCC_GPIOG_CLK_ENABLE();
 __HAL_RCC_GPIOE_CLK_ENABLE();

 /*Configure GPIO pin Output Level */
 HAL_GPIO_WritePin(DEBUG_OUTPUT_GPIO_Port, DEBUG_OUTPUT_Pin, GPIO_PIN_RESET);

 /*Configure GPIO pin Output Level */
 HAL_GPIO_WritePin(YELLOW_LED_GPIO_Port, YELLOW_LED_Pin, GPIO_PIN_RESET);

 /*Configure GPIO pin : DEBUG_OUTPUT_Pin */
 GPIO_InitStruct.Pin = DEBUG_OUTPUT_Pin;
 GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
 GPIO_InitStruct.Pull = GPIO_NOPULL;
 GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_MEDIUM;
 HAL_GPIO_Init(DEBUG_OUTPUT_GPIO_Port, &GPIO_InitStruct);

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

 /* USER CODE BEGIN MX_GPIO_Init_2 */

 /* USER CODE END MX_GPIO_Init_2 */
}

/* USER CODE BEGIN 4 */

/* USER CODE END 4 */

/**
 * @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 */