Can't get RX callback interrupt to be triggered

Digital101 · ‎2021-11-16

I've followed this tutorial word by word and I'm not entirely sure why:

1) Nothing is being written to that rx_buffer[]

2) Why the void HAL_UART_RxCpltCallback(UART_HandleTypeDef *huart) isn't being called/triggered as shown in the video

I'm also using the STM32F411RE Nucleo board

Here's the link to the mentioned tutorial : https://www.youtube.com/watch?v=5i-Gw7OC7oo&t=2s&ab_channel=STMicroelectronics

I have a jumper wire going from D8 to D2 that would connect the UART RX and TX pins.

And I'm using RealTerm to monitor the output and I am getting all the values of the buffer_tx[] being output on there.

I've also included both the .ioc file and my main.c file to this post

I know I'm not dishing out many details at the moment, but I'm not sure what else to include that would be relevant/helpful to resolve the issue I'm currently facing.

CPINA · ‎2021-11-17

Hello,

did you check with an oscilloscope that what you got on TX pins you have it on RX Pins on the corresponding GPIO ? Which product is targeted (package as well) and which tutorial are you running ?

Best regards,

Christophe

Digital101 · ‎2021-11-17

I, unfortunately, don't have an oscilloscope.

Regarding the product that's targeted, I'm assuming you meant which board I'm using? If so, I'm using the STM32F411RE Nucelo board

And I'm following this tutorial : https://www.youtube.com/watch?v=5i-Gw7OC7oo&t=2s&ab_channel=STMicroelectronics

CPINA · ‎2021-11-18

It looks like the link to the reception in not good. are you well handling the pin affectation for RX and TX into the stm32f4xx_hal_msp.c files as well as the correct alternate function number set ?

CPINA · ‎2021-11-18

Are you entering in your RX callback (complete callback) setting up a break point in your while (1) inside this callback in your main ?

Digital101 · ‎2021-11-18

I'm not sure what you mean when you mentioned:

'are you handling the pin affection for RX and TX into the stm32f4xx_hal_msp.c files as well as the correct alternate function number set'

If it helps, here's my stm32f4xx_hal_msp.c file

/* USER CODE BEGIN Header */
/**
  ******************************************************************************
  * @file         stm32f4xx_hal_msp.c
  * @brief        This file provides code for the MSP Initialization
  *               and de-Initialization codes.
  ******************************************************************************
  * @attention
  *
  * <h2><center>&copy; Copyright (c) 2021 STMicroelectronics.
  * All rights reserved.</center></h2>
  *
  * This software component is licensed by ST under BSD 3-Clause license,
  * the "License"; You may not use this file except in compliance with the
  * License. You may obtain a copy of the License at:
  *                        opensource.org/licenses/BSD-3-Clause
  *
  ******************************************************************************
  */
/* USER CODE END Header */
 
/* Includes ------------------------------------------------------------------*/
#include "main.h"
/* USER CODE BEGIN Includes */
 
/* USER CODE END Includes */
 
/* Private typedef -----------------------------------------------------------*/
/* USER CODE BEGIN TD */
 
/* USER CODE END TD */
 
/* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN Define */
 
/* USER CODE END Define */
 
/* Private macro -------------------------------------------------------------*/
/* USER CODE BEGIN Macro */
 
/* USER CODE END Macro */
 
/* Private variables ---------------------------------------------------------*/
/* USER CODE BEGIN PV */
 
/* USER CODE END PV */
 
/* Private function prototypes -----------------------------------------------*/
/* USER CODE BEGIN PFP */
 
/* USER CODE END PFP */
 
/* External functions --------------------------------------------------------*/
/* USER CODE BEGIN ExternalFunctions */
 
/* USER CODE END ExternalFunctions */
 
/* USER CODE BEGIN 0 */
 
/* USER CODE END 0 */
/**
  * Initializes the Global MSP.
  */
void HAL_MspInit(void)
{
  /* USER CODE BEGIN MspInit 0 */
 
  /* USER CODE END MspInit 0 */
 
  __HAL_RCC_SYSCFG_CLK_ENABLE();
  __HAL_RCC_PWR_CLK_ENABLE();
 
  /* System interrupt init*/
 
  /* USER CODE BEGIN MspInit 1 */
 
  /* USER CODE END MspInit 1 */
}
 
/**
* @brief UART MSP Initialization
* This function configures the hardware resources used in this example
* @param huart: UART handle pointer
* @retval None
*/
void HAL_UART_MspInit(UART_HandleTypeDef* huart)
{
  GPIO_InitTypeDef GPIO_InitStruct = {0};
  if(huart->Instance==USART1)
  {
  /* USER CODE BEGIN USART1_MspInit 0 */
 
  /* USER CODE END USART1_MspInit 0 */
    /* Peripheral clock enable */
    __HAL_RCC_USART1_CLK_ENABLE();
 
    __HAL_RCC_GPIOA_CLK_ENABLE();
    /**USART1 GPIO Configuration
    PA9     ------> USART1_TX
    PA10     ------> USART1_RX
    */
    GPIO_InitStruct.Pin = GPIO_PIN_9|GPIO_PIN_10;
    GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
    GPIO_InitStruct.Pull = GPIO_NOPULL;
    GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
    GPIO_InitStruct.Alternate = GPIO_AF7_USART1;
    HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
 
    /* USART1 interrupt Init */
    HAL_NVIC_SetPriority(USART1_IRQn, 0, 0);
    HAL_NVIC_EnableIRQ(USART1_IRQn);
  /* USER CODE BEGIN USART1_MspInit 1 */
 
  /* USER CODE END USART1_MspInit 1 */
  }
 
}
 
/**
* @brief UART MSP De-Initialization
* This function freeze the hardware resources used in this example
* @param huart: UART handle pointer
* @retval None
*/
void HAL_UART_MspDeInit(UART_HandleTypeDef* huart)
{
  if(huart->Instance==USART1)
  {
  /* USER CODE BEGIN USART1_MspDeInit 0 */
 
  /* USER CODE END USART1_MspDeInit 0 */
    /* Peripheral clock disable */
    __HAL_RCC_USART1_CLK_DISABLE();
 
    /**USART1 GPIO Configuration
    PA9     ------> USART1_TX
    PA10     ------> USART1_RX
    */
    HAL_GPIO_DeInit(GPIOA, GPIO_PIN_9|GPIO_PIN_10);
 
    /* USART1 interrupt DeInit */
    HAL_NVIC_DisableIRQ(USART1_IRQn);
  /* USER CODE BEGIN USART1_MspDeInit 1 */
 
  /* USER CODE END USART1_MspDeInit 1 */
  }
 
}
 
/* USER CODE BEGIN 1 */
 
/* USER CODE END 1 */
 
/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/

Digital101 · ‎2021-11-18

I did set up a breakpoint at the RX callback and implemented a while(1) loop in there as stated below

void HAL_UART_TxCpltCallback(UART_HandleTypeDef *huart)
{
 
}
void HAL_UART_RxCpltCallback(UART_HandleTypeDef *huart)
{
  while(1);
}

Here's the rest of my main.c file

/* USER CODE BEGIN Header */
/**
  ******************************************************************************
  * @file           : main.c
  * @brief          : Main program body
  ******************************************************************************
  * @attention
  *
  * <h2><center>&copy; Copyright (c) 2021 STMicroelectronics.
  * All rights reserved.</center></h2>
  *
  * This software component is licensed by ST under BSD 3-Clause license,
  * the "License"; You may not use this file except in compliance with the
  * License. You may obtain a copy of the License at:
  *                        opensource.org/licenses/BSD-3-Clause
  *
  ******************************************************************************
  */
/* USER CODE END Header */
/* Includes ------------------------------------------------------------------*/
#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 */
/* USER CODE END PD */
 
/* Private macro -------------------------------------------------------------*/
/* USER CODE BEGIN PM */
 
/* USER CODE END PM */
 
/* Private variables ---------------------------------------------------------*/
UART_HandleTypeDef huart1;
 
/* USER CODE BEGIN PV */
uint8_t buffer_tx[10] = {0,1,2,3,4,5,6,7,8,9};
uint8_t buffer_rx[10];
 
/* USER CODE END PV */
 
/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_USART1_UART_Init(void);
/* USER CODE BEGIN PFP */
 
/* USER CODE END PFP */
 
/* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 */
void HAL_UART_TxCpltCallback(UART_HandleTypeDef *huart)
{
 
}
void HAL_UART_RxCpltCallback(UART_HandleTypeDef *huart)
{
  while(1);
}
/* 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_USART1_UART_Init();
  /* USER CODE BEGIN 2 */
  HAL_GPIO_WritePin(GPIOA, GPIO_PIN_5, 1);
  HAL_UART_Receive_IT(&huart1, buffer_rx, 10);
  HAL_UART_Transmit_IT(&huart1, buffer_tx, 10);
  HAL_GPIO_WritePin(GPIOA, GPIO_PIN_5, 0);
 
  /* USER CODE END 2 */
 
  /* Infinite loop */
  /* USER CODE BEGIN WHILE */
  while (1)
  {
    /* USER CODE END WHILE */
 
    /* USER CODE BEGIN 3 */
  }
  /* USER CODE END 3 */
}
 
/**
  * @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_RCC_PWR_CLK_ENABLE();
  __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_OscInitStruct.HSIState = RCC_HSI_ON;
  RCC_OscInitStruct.HSICalibrationValue = RCC_HSICALIBRATION_DEFAULT;
  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_NONE;
  if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
  {
    Error_Handler();
  }
  /** Initializes the CPU, AHB and APB buses clocks
  */
  RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
                              |RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2;
  RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_HSI;
  RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
  RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;
  RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;
 
  if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_0) != HAL_OK)
  {
    Error_Handler();
  }
}
 
/**
  * @brief USART1 Initialization Function
  * @param None
  * @retval None
  */
static void MX_USART1_UART_Init(void)
{
 
  /* USER CODE BEGIN USART1_Init 0 */
 
  /* USER CODE END USART1_Init 0 */
 
  /* USER CODE BEGIN USART1_Init 1 */
 
  /* USER CODE END USART1_Init 1 */
  huart1.Instance = USART1;
  huart1.Init.BaudRate = 115200;
  huart1.Init.WordLength = UART_WORDLENGTH_8B;
  huart1.Init.StopBits = UART_STOPBITS_1;
  huart1.Init.Parity = UART_PARITY_NONE;
  huart1.Init.Mode = UART_MODE_TX_RX;
  huart1.Init.HwFlowCtl = UART_HWCONTROL_NONE;
  huart1.Init.OverSampling = UART_OVERSAMPLING_16;
  if (HAL_UART_Init(&huart1) != HAL_OK)
  {
    Error_Handler();
  }
  /* USER CODE BEGIN USART1_Init 2 */
 
  /* USER CODE END USART1_Init 2 */
 
}
 
/**
  * @brief GPIO Initialization Function
  * @param None
  * @retval None
  */
static void MX_GPIO_Init(void)
{
  GPIO_InitTypeDef GPIO_InitStruct = {0};
 
  /* GPIO Ports Clock Enable */
  __HAL_RCC_GPIOA_CLK_ENABLE();
 
  /*Configure GPIO pin Output Level */
  HAL_GPIO_WritePin(GPIOA, GPIO_PIN_5, GPIO_PIN_RESET);
 
  /*Configure GPIO pin : PA5 */
  GPIO_InitStruct.Pin = GPIO_PIN_5;
  GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
  HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
 
}
 
/* 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 */
 
/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/

CPINA · ‎2021-11-18

I do not see at first glance something wrong in your code... Are you sure about your connection (physical connection to connect Tx to RX (Pin 3 CN9 D2 connected to D8 pin 1 CN5) ? If yes, if you put a breakpoint into the RX callback and TX callback, are you able to stop to one of the breakpoint (I suppose yes, because you said that you are able to validate that TX is well running on the output sending the buffer_tx) ?

Digital101 · ‎2021-11-18

Below is the datasheet that I referenced to make the connection with the yellow jumper cable (which I tested with a continuity check to keep my sanity which checks out fine)

When I placed both a while(1) loop and breakpoints that both RX/TX call back function calls, neither of them are being triggered and are being 'skipped over' when I'm 'Stepping through' the entire code in Debug mode