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Visitor II
December 10, 2024
Question

Black screen when enabling "Debug: Serial Wire"

  • December 10, 2024
  • 4 replies
  • 767 views

Hi guys,

 

I bought a STM32F469I-Disco Board. I have played around with TouchGFX example projects and had success adding an ADC (ADC1_IN9 connected to Pin PB1) conversion to the project and display the value on the touch display as text in a textArea as well as with a gauge.

I use DMA in circular mode and enabled cont. conversion and cont. requests. I use a task and queue in FREERTOS and as I said that part works fine.

Then I wanted to add UART to that project which should prompt a text every second. I chose USART3 because Pins PB10 and PB11 are connected to the virtual COM port of the built-in STLink. I activated Debug serial Wire under System Core / Sys because the tutorial I followed said so. Timebase source is TIM6.

The project compiles without errors. But when I flash the board the screen stays black.

Then I tried to revert erverything regarding UART and Debug Serial Wire (deactivate USART3, disable Debug) but the screen stays black.

 

Any Ideas? Thanks.

 

EDIT: The same happens to any other project. E.g. the DiceAnimation Demo in TouchGFX Designer: When I create the project new and flash the board it works just fine. When I then activate Degub: Serial Wire in Sys the screen is black after flashing and the project can not be recovered. Even when I deactive Debug Serial Wire again, the screen is black.

    This topic has been closed for replies.

    4 replies

    Technical Moderator
    January 10, 2025

    Hello @JanGlueck and welcome to the community,

     

    Could you try running through the debug and see if the code is stuck in a HAL infinite loop? May be this post can help you: TouchGFX - Serial Wire debug problem.

     

    Thank you.

    Kaouthar

    JanGlueckAuthor
    Visitor II
    January 13, 2025

    Hello Kaouthar,

     

    thank you for looking into this.

    I don't have this exact project anymore.

     

    But I run into the same issue quite often: Project compiles without error, flashes, but screen stays black.

    I started a blank TouchGFX project with only one screen and only one background image, no text, no button, nothing.

     

    No serial wire debug.

    Then I started adding things in CubeIDE: one timer that flashes one user LED (TIM2) and another timer that flashes another user LED (TIM9). That worked fine.

    Then I wanted to add a DAC in DMA mode which should generate a sinewave. TIM7 is used to trigger the DAC. But already then I get the black sceen and also the LEDs do not flash. I increased the stack size of the defaultTask from 128 to 2048 but no luck. Then I deactivated the DAC again but I can't get the program to start anymore.

     

    void StartDefaultTask(void *argument)
    {
     /* USER CODE BEGIN 5 */
    
    	HAL_TIM_Base_Start_IT(&htim2);
    	HAL_TIM_Base_Start_IT(&htim9);
    	HAL_TIM_Base_Start_IT(&htim7);
    
    	HAL_DAC_Start_DMA(&hdac,DAC_CHANNEL_1, (uint32_t*) &dma_buffer, 2 * DMA_BUFFER_SIZE, DAC_ALIGN_12B_R);
    
    
     /* Infinite loop */
     for(;;)
     {
     osDelay(100);
     }
     /* USER CODE END 5 */
    }

     

     

    Right now, the MX_TouchGFX_Init(); does not finish. See screenshot.

    JanGlueck_0-1736756054548.png

    EDIT:

    We seem to stop here:

    JanGlueck_1-1736757264914.png

     

    Technical Moderator
    January 13, 2025

    Hello @JanGlueck,

     

    Thank you for updating this post.

    Could you share the STM32F469I-DISCO board revision and the software versions STM32CubeIDE, TouchGFX? Are you using the latest software versions? 

     

    Thank you.

    Kaouthar

     

    JanGlueckAuthor
    Visitor II
    January 14, 2025

    Hello @KDJEM.1,

    CubeIDE Version: 1.17.0

    JanGlueck_0-1736835775734.png

    TouchGFX Version: 4.24.1

    JanGlueck_1-1736835839539.png

    I always used this board in TouchGFX: 

    JanGlueck_2-1736835909500.png

     

    Disco Board Version:

    20250114_072013.jpg

    20250114_072045.jpg

     

    Thanks,

    Jan