Read parallel data that is valid in every falling edge clock nucleo-h743ZI2

[AElta.1]

Hello

I have an external adc with 2 parallel output pins each is 1 bit (2 bits) total, with clK_out pin, I am trying to read the parallel pins using nucleo-h743ZI2 (480Mhz), I followed [AN4666] example to receive the data1, clk_out is connected to PA6 which is defined as a TIMER in input capture and it triggers the DMA to GPIO pins and save it into memory. Unfortunately my code read the pins only once and I was expecting that it would read every falling edge of the clk_out. all I trying to do is make the dma read every falling edge. here is my code I would really appreciate all the help I can get.

#include "main.h"
 
/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
 
/* USER CODE END Includes */
 
/* Private typedef -----------------------------------------------------------*/
/* USER CODE BEGIN PTD */
 
/* USER CODE END PTD */
 
/* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD */
#define MAX_FRAME_SIZE 100
#define BUFFER_SIZE    20
#define HALF_BUFFER_SIZE  BUFFER_SIZE/2
/* USER CODE END PD */
 
/* Private macro -------------------------------------------------------------*/
/* USER CODE BEGIN PM */
volatile int LastITHalfComplete = 0;
volatile int32_t FullDataIndex = 0;
volatile int i = 0;
volatile uint8_t  transferComplete = 0;
/* USER CODE END PM */
 
/* Private variables ---------------------------------------------------------*/
 
TIM_HandleTypeDef htim1;
DMA_HandleTypeDef hdma_tim1_ch1;
 
UART_HandleTypeDef huart3;
 
PCD_HandleTypeDef hpcd_USB_OTG_FS;
 
/* USER CODE BEGIN PV */
static uint8_t aFull_Buffer[MAX_FRAME_SIZE] = {0};
static uint8_t aDST_Buffer[BUFFER_SIZE] = {0};
/* USER CODE END PV */
 
/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_USART3_UART_Init(void);
static void MX_USB_OTG_FS_PCD_Init(void);
static void MX_TIM1_Init(void);
static void MX_DMA_Init(void);
/* USER CODE BEGIN PFP */
static void TransferComplete(DMA_HandleTypeDef *hdma_tim1_ch1);
static void TransferError(DMA_HandleTypeDef *hdma_tim1_ch1);
static void HalfTransferComplete(DMA_HandleTypeDef *hdma_tim1_ch1);
/* USER CODE END PFP */
 
/* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 */
 
/* USER CODE END 0 */
 
/**
  * @brief  The application entry point.
  * @retval int
  */
int main(void)
{
  /* USER CODE BEGIN 1 */
 
  /* USER CODE END 1 */
 
  /* 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_USART3_UART_Init();
  MX_USB_OTG_FS_PCD_Init();
  MX_TIM1_Init();
  MX_DMA_Init();
  /* USER CODE BEGIN 2 */
  // Attach DMA callback functions
  	htim1.hdma[TIM_DMA_ID_CC1]->XferHalfCpltCallback = HalfTransferComplete;
  	htim1.hdma[TIM_DMA_ID_CC1]->XferCpltCallback = TransferComplete;
  	htim1.hdma[TIM_DMA_ID_CC1]->XferErrorCallback = TransferError;
 
  	// Start DMA in interrupt mode, specify source and destination
 
  	HAL_DMA_Start_IT(htim1.hdma[TIM_DMA_ID_CC1], (uint32_t) &GPIOC->IDR, (uint32_t) &aDST_Buffer, 1);
 
 
  	// Enable timer to trigger DMA transfer - CC1DE bit
  	__HAL_TIM_ENABLE_DMA(&htim1, TIM_DMA_CC1);
 
  	// Enable timer input capture
  	HAL_TIM_IC_Start(&htim1, TIM_CHANNEL_1);
  /* USER CODE END 2 */
 
  /* Infinite loop */
  /* USER CODE BEGIN WHILE */
  	 /* USER CODE BEGIN WHILE */
  		while (1) {
  			//if (transferComplete) {
  				//transferComplete = 0;
  				// Transmit buffer to UART
  				// Prepare data into buffer
  				//HAL_UART_Transmit_IT(&huart3, buff, LEN);
  			//}
 
    /* USER CODE END WHILE */
 
    /* USER CODE BEGIN 3 */
  		}
  /* USER CODE END 3 */
}

the interrupts

static void HalfTransferComplete(DMA_HandleTypeDef *hdma_tim1_ch1) {
	int position = 0;
	  LastITHalfComplete = 1;
	  /*Copy the first part of the received buffer */
	   for (int i = 0; i < HALF_BUFFER_SIZE; i++)
	   {
	     aFull_Buffer[FullDataIndex] = aDST_Buffer[i+position];
	     FullDataIndex++;
	     HAL_GPIO_TogglePin(GPIOE, GPIO_PIN_1);
}
 
}
static void TransferComplete(DMA_HandleTypeDef *hdma_tim1_ch1) {
	int position = HALF_BUFFER_SIZE;
	  LastITHalfComplete = 0;
 
	  /* Copy the second part of the received buffer */
	  for (int i = 0; i < HALF_BUFFER_SIZE; i++)
	  {
	    aFull_Buffer[FullDataIndex] = aDST_Buffer[i+position];
	    FullDataIndex++;
	    HAL_GPIO_TogglePin(GPIOB, GPIO_PIN_0);
	  }
 
 
	transferComplete = 1;
}
 
static void TransferError(DMA_HandleTypeDef *hdma_tim1_ch1) {
	HAL_GPIO_TogglePin(GPIOB,GPIO_PIN_14);
}
 
void HAL_UART_TxCpltCallback(UART_HandleTypeDef *huart3) {
	// Enable again DMA for a new transfer
	HAL_DMA_Start_IT(htim1.hdma[TIM_DMA_ID_CC1], (uint32_t) &GPIOC->IDR, (uint32_t) aDST_Buffer, BUFFER_SIZE);
}

Thank you in advance

[KDJEM.1]

Hello @AElta.1​,

Which STM32CubeMX version are you using?

If you use the STM32CubeMX 6.7.0 ​ version could you please share the .ioc file?

Try to move the MX_DMA_Init(); line code before MX_USART3_UART_Init(); in your main.c.

When your question is answered, please close this topic by choosing Select as Best. This will help other users find that answer faster.

Kaouthar