STM32CubeMX and BUG in UART_DMATransmitCplt

[Davydenko.Sergey]

Posted on November 02, 2015 at 12:53

STM32CubeMX V4.11

STM32Cube FW_F4 V1.9.0

/**

  ******************************************************************************

  * @file    stm32f4xx_hal_uart.c

  * @author  MCD Application Team

  * @version V1.4.1

  * @date    09-October-2015

  * @brief   UART HAL module driver.

  *          This file provides firmware functions to manage the following 

  *          functionalities of the Universal Asynchronous Receiver Transmitter (UART) peripheral:

  *           + Initialization and de-initialization functions

  *           + IO operation functions

  *           + Peripheral Control functions  

  *           + Peripheral State and Errors functions  

  *           

  @verbatim       

.......

/**

  * @brief  DMA UART transmit process complete callback. 

  * @param  hdma: DMA handle

  * @retval None

  */

static void UART_DMATransmitCplt(DMA_HandleTypeDef *hdma)

{

  UART_HandleTypeDef* huart = ( UART_HandleTypeDef* )((DMA_HandleTypeDef* )hdma)->Parent;

  /* DMA Normal mode*/

  if((hdma->Instance->CR & DMA_SxCR_CIRC) == 0)

  {

    huart->TxXferCount = 0;

    /* Disable the DMA transfer for transmit request by setting the DMAT bit

       in the UART CR3 register */

    huart->Instance->CR3 &= (uint32_t)~((uint32_t)USART_CR3_DMAT);

    /* Enable the UART Transmit Complete Interrupt */

    __HAL_UART_ENABLE_IT(huart, UART_IT_TC);

  }

  /* DMA Circular mode */

  else

  {

    HAL_UART_TxCpltCallback(huart);

  }

}

very similar to that lacks the following code fragment:

    if(huart->State == HAL_UART_STATE_BUSY_TX_RX) 

    {

      huart->State = HAL_UART_STATE_BUSY_RX;

    }

    else

    {

      huart->State = HAL_UART_STATE_READY;

    }

as in

/**

  * @brief  DMA UART receive process complete callback. 

  * @param  hdma: DMA handle

  * @retval None

  */

static void UART_DMAReceiveCplt(DMA_HandleTypeDef *hdma)  

{

  UART_HandleTypeDef* huart = ( UART_HandleTypeDef* )((DMA_HandleTypeDef* )hdma)->Parent;

  /* DMA Normal mode*/

  if((hdma->Instance->CR & DMA_SxCR_CIRC) == 0)

  {

    huart->RxXferCount = 0;

  

    /* Disable the DMA transfer for the receiver request by setting the DMAR bit 

       in the UART CR3 register */

    huart->Instance->CR3 &= (uint32_t)~((uint32_t)USART_CR3_DMAR);

    /* Check if a transmit process is ongoing or not */

    if(huart->State == HAL_UART_STATE_BUSY_TX_RX) 

    {

      huart->State = HAL_UART_STATE_BUSY_TX;

    }

    else

    {

      huart->State = HAL_UART_STATE_READY;

    }

  }

  HAL_UART_RxCpltCallback(huart);

}

[Nickname5522_O]

Posted on November 02, 2015 at 16:14

Hi davydenko.sergey,

Did you face any problem when running this code? Could you please explain the reason for giving your proposal?

Kind regards,

-Shahrzad-

[Davydenko.Sergey]

Posted on November 04, 2015 at 18:25

Hello Shahrzad

Yes, I have encountered this problem.

When the DMA USART used in normal mode and a data packet sent by the DMA periodically.

Dispatched only the first packet and a single.

HAL_UART_Transmit_DMA (...)

All subsequent attempts to send a packet, return status HAL_BUSY.

When sending a packet status is set

huart-> State = HAL_UART_STATE_BUSY_TX_RX

or

huart-> State = HAL_UART_STATE_BUSY_TX

This status after completion of sending must be changed to

HAL_UART_STATE_BUSY_RX

or

HAL_UART_STATE_READY

Otherwise, the next attempt to send the packet does not lead to the desired result.

It is necessary to fix the problem in the procedure 

UART_DMATransmitCplt

and also the procedure

HAL_UART_TxCpltCallback (huart)

It will be carried out only in the case of circular DMA that is not right ...

May be next:

static void USER_UART_DMATransmitCplt(DMA_HandleTypeDef *hdma)

{

  UART_HandleTypeDef* huart = ( UART_HandleTypeDef* )((DMA_HandleTypeDef* )hdma)->Parent;

  /* DMA Normal mode*/

  if((hdma->Instance->CR & DMA_SxCR_CIRC) == 0)

  {

    huart->TxXferCount = 0;

    /* Disable the DMA transfer for transmit request by setting the DMAT bit

       in the UART CR3 register */

    huart->Instance->CR3 &= (uint32_t)~((uint32_t)USART_CR3_DMAT);

    /* Check if a recieve process is ongoing or not */

    if(huart->State == HAL_UART_STATE_BUSY_TX_RX) 

    {

      huart->State = HAL_UART_STATE_BUSY_RX;

    }

    else

    {

      huart->State = HAL_UART_STATE_READY;

    }

  }

  

  HAL_UART_TxCpltCallback(huart);

}

It worked!!!

But maybe I'm wrong ...

Kind regards,

Sergei Davydenko

[Nickname5522_O]

Posted on January 28, 2016 at 15:14

Hi davydenko.sergey,

The issue is already treated by our development team, and modifications will be delivered in next releases of STM32Cube.

-Shahrzad-

[kaihofmann]

Posted on June 08, 2016 at 16:10

Hello Shahrzad

,

using the current version of STM32CubeMX 4.15.0 and FWV 1.12.0 the problem is still there (stm32f4xx_hal_uart.c, MCD Application Team, version V1.5.0).

I fixed the UART_DMATransmitCplt function in the same way as Sergey did (just replaced huart->state by huart->gstate) ...and DMA transmit works.

I wonder what is the intended way to make the ''normal DMA'' mode work from scratch? Or did you just missed to fix this bug in this release?

Best regards,

Kai

[Amel NASRI]

Posted on June 08, 2016 at 16:24

Hi hofmann.kai,

This is not a bug, but you need to enable the USART handler in the it.c file to handle the transfer complete.

You may find more explanation in [DEAD LINK /public/STe2ecommunities/mcu/Lists/STM32Java/Flat.aspx?RootFolder=/public/STe2ecommunities/mcu/Lists/STM32Java/HAL%20Without%20USART%20interrupt%2c%20HAL_UART_Transmit_DMA%28%29%20will%20work%20only%20once&FolderCTID&currentviews=64]this discussion.

-Mayla-

[kaihofmann]

Posted on June 09, 2016 at 11:36

Hi Mayla,

thank you Mayla, for your fast reply. I read the article, but honestly I do not understand where to enable/realize the handler exactly.

Could you please give me some example code?

Thanks in advance.

Kai

[Amel NASRI]

Posted on June 09, 2016 at 15:37

Hihofmann.kai,

I suggest you refer to any USART example using DMA (Ex:STM32Cube_FW_F4_V1.0\Projects\STM32F4-Discovery\Examples\UART\UART_TwoBoards_ComDMA).

You can see that in the file stm32f4xx_it.c we have:

/**

* @brief This function handles DMA RX interrupt request.

* @param None

* @retval None

*/

void

USARTx_DMA_RX_IRQHandler(

void

)

{

HAL_DMA_IRQHandler(UartHandle.hdmarx);

}

/**

* @brief This function handles DMA TX interrupt request.

* @param None

* @retval None

*/

void

USARTx_DMA_TX_IRQHandler(

void

)

{

HAL_DMA_IRQHandler(UartHandle.hdmatx);

}

/**

* @brief This function handles USARTx interrupt request.

* @param None

* @retval None

*/

void

USARTx_IRQHandler(

void

)

{

HAL_UART_IRQHandler(&UartHandle);

}

-Mayla-