HAL UART Transmit problem

Posted on November 08, 2015 at 21:19

I have a running project with STM32F103 and I wanted to add UART Transmit to do some debugging but HAL_UART_Transmit does not work and does not transmit any data. I have chosen USART2 and PD.5 and PD.6 pins as the interface. The weird thing is that when I create a new project using STM32cubemx the UART does work. But when I implement necessary changes into my first project the UART does not work. I checked a lot of times for something maybe missing but yet have not figured this out. 

Here's what I did: 

First enabled HAL_UART_MODULE_ENABLED in stm32f1xx_hal_conf.h

Then :

UART_HandleTypeDef huart2;

Init function which will be called in main:

void UART_Config(void)

{

  /* UARTx configured as follow:

        - BaudRate = 115200 baud  

        - Word Length = 8 Bits

        - One Stop Bit

        - No parity

        - Hardware flow control disabled (RTS and CTS signals)

        - Receive and transmit enabled

  */

/* Peripheral clock enable */

 huart2.Instance = USART2;

 huart2.Init.BaudRate = 38400;

 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;

 HAL_UART_Init(&huart2);

}

And HAL_UART_MspInit() to init PD.5 and PD.6 which will be called at the end of above code:

void HAL_UART_MspInit(UART_HandleTypeDef* huart)

{

  GPIO_InitTypeDef GPIO_InitStruct;

  if(huart->Instance==USART2)

  {

  /* USER CODE BEGIN USART2_MspInit 0 */

  /* USER CODE END USART2_MspInit 0 */

    /* Peripheral clock enable */

    __USART2_CLK_ENABLE();

    /**USART2 GPIO Configuration

    PD5     ------> USART2_TX

    PD6     ------> USART2_RX

    */

    GPIO_InitStruct.Pin = GPIO_PIN_5;

    GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;

    GPIO_InitStruct.Speed = GPIO_SPEED_HIGH;

    HAL_GPIO_Init(GPIOD, &GPIO_InitStruct);

    GPIO_InitStruct.Pin = GPIO_PIN_6;

    GPIO_InitStruct.Mode = GPIO_MODE_INPUT;

    GPIO_InitStruct.Pull = GPIO_NOPULL;

    HAL_GPIO_Init(GPIOD, &GPIO_InitStruct);

    __HAL_AFIO_REMAP_USART2_ENABLE();

  /* USER CODE BEGIN USART2_MspInit 1 */

  /* USER CODE END USART2_MspInit 1 */

  }

}

Then I'm simply calling HAL_UART_Transmit() in the main function after the initialization of all the peripherals like this :

  HAL_UART_Transmit(&huart2, ''Hello\n'', 6, 10);

But I don't see anything in terminal and I assure you the hardware and connections and things like that are fine considering it all work with a new project. But since I have lots of code in this project I figured it would be easier to insert UART in this project instead of doing the other way around. 

It's not supposed to be this hard getting a simple UART to work. 

Could you guys help me? 

#uart