STM32 - USART1 & USART2 (USART2 non working)

[SMusc.1]

Hello everyone, I am having a problem with a simple program. My board is a STM32-U575ZITxQ.
Using only the USART1 interface, if I try to print the string: "USART1_READY" on my laptop's serial port, I have no problem. However, as soon as I also enable the USART2, I cannot print anything. Whether with only the USART2 enabled, or with both USART1 and USART2 enabled, if I try to print the string with USART2, I cannot. I checked all the settings of the USART1 and USART2 and they are the same (in GPIO, in Parameter setting, etc.).

/* USER CODE BEGIN PV */
char USART1 = "USART1_READY:\r\n";
char USART2= "USART2_READY:\r\n";
/* USER CODE END PV */

/* USER CODE BEGIN 2 */
HAL_TIM_Base_Start_IT(&htim4);//ready for trigger at 1 seconds
/* USER CODE END 2 */

void HAL_TIM_PeriodElapsedCallback(TIM_HandleTypeDef *htim)
{
    if(htim->Instance == TIM4)
       {
      //HAL_UART_Transmit(&huart1, &USART1, sizeof(USART1),HAL_MAX_DELAY);
        HAL_UART_Transmit(&huart2, &USART2, sizeof(USART2),HAL_MAX_DELAY);
       }
}

where am I going wrong?

[Andrew Neil]

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@SMusc.1 wrote:

 VCP is the com serial port of laptop right? 

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"VCP" = Virtual COM Port - it is part of the ST-Link on the board:

https://www.st.com/resource/en/user_manual/um2861-stm32u5-nucleo144-board-mb1549-stmicroelectronics.pdf#page=10

via: https://www.st.com/en/evaluation-tools/nucleo-u575zi-q.html#documentation

[SMusc.1]

I am using a simple USB cable connected to USB port of my laptop tho the board. I see that the port com associate to this connection is any time COM4. How can i know which com port are used from USART2 and USART3 of my nucleo board?

[Andrew Neil]

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@SMusc.1 wrote:

I am using a simple USB cable connected to USB port of my laptop tho the board. I see that the port com associate to this connection is any time COM4. 

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That is the VCP of the ST-Link - see my previous post

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@SMusc.1 wrote:

How can i know which com port are used from USART2 and USART3 of my nucleo board?

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There is no other COM port.

If you want additional COM ports to connect to those UARTs, you will need to provide them yourself; eg, using  USB-to-UART adaptors or cables

https://shop.pimoroni.com/products/cp2102-usb-to-serial-uart-with-usb-type-c-plug?variant=39428362207315

https://uk.rs-online.com/web/p/development-tool-accessories/6877770 

[SMusc.1]

okay clear, tks a lot to everyone