No Output on Serial Monitor with printf() and UART

[Blankshiori]

Hi, I am using the STM32F401CEU6 and I was following the tutorial to use printf() with UART, but I am not getting any output on the serial monitor.

Also in the code snippet given in the Lesson1 you have not included "stdio.h" but my IDE is asking to include the same because it does not recognize the "FILE" in fpuct() function. I've also given the error message in the bottom.

My Code given below: +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

#include "main.h"

#include "stm32f4xx_hal.h" #include "stdio.h"

UART_HandleTypeDef huart2;

void SystemClock_Config(void); static void MX_GPIO_Init(void); static void MX_USART2_UART_Init(void);

int fputc(int ch, FILE *f) { HAL_UART_Transmit(&huart2, (unsigned char *)&ch, 1, 100); return ch; }

int main(void) {

HAL_Init();

SystemClock_Config();

MX_GPIO_Init(); MX_USART2_UART_Init();

while (1) { /* USER CODE END WHILE */

/* USER CODE BEGIN 3 */
  HAL_GPIO_TogglePin(GPIOC,GPIO_PIN_13);
  printf("Hello World\n");
  HAL_Delay(500);

}

}

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_SCALE2);

/** 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 USART2 Initialization Function
• @param None
• @retval None */ static void MX_USART2_UART_Init(void) {

/* USER CODE BEGIN USART2_Init 0 */

/* USER CODE END USART2_Init 0 */

/* USER CODE BEGIN USART2_Init 1 */

/* USER CODE END USART2_Init 1 / huart2.Instance = USART2; huart2.Init.BaudRate = 115200; huart2.Init.WordLength = UART_WORDLENGTH_8B; huart2.Init.StopBits = UART_STOPBITS_1; huart2.Init.Parity = UART_PARITY_NONE; huart2.Init.Mode = UART_MODE_TX_RX; huart2.Init.HwFlowCtl = UART_HWCONTROL_NONE; huart2.Init.OverSampling = UART_OVERSAMPLING_16; if (HAL_UART_Init(&huart2) != HAL_OK) { Error_Handler(); } / USER CODE BEGIN USART2_Init 2 */

/* USER CODE END USART2_Init 2 */

}

/**

• @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_GPIOA_CLK_ENABLE();

/*Configure GPIO pin Output Level */ HAL_GPIO_WritePin(GPIOC, GPIO_PIN_13, GPIO_PIN_RESET);

/*Configure GPIO pin : PC13 */ GPIO_InitStruct.Pin = GPIO_PIN_13; GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP; GPIO_InitStruct.Pull = GPIO_PULLDOWN; GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW; HAL_GPIO_Init(GPIOC, &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 */

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

ERROR Message if i dont include the "stdio.h".