USB_CDC and BLE Hard Fault

[BMart.2]

Hello,

I'm using CubeMx to create a project with usb cdc serial port and BLE functionality. CubeMx generates a sequencer UTIL_SEQ_Run(~0); that runs the BLE state machine. In the code below, if I comment out UTIL_SEQ_Run(~0); the code runs fine per Workshop #3 on Youtube. Prints out the data "Hello World" to hyperterminal. As soon as I uncomment UTIL_SEQ_Run(~0); and run the app in the debugger I get a hard fault. Has anyone seen this behavior while trying to run the sequencer with usb cdc? Any thoughts as to how to debug this as far as where I should start looking?

Thanks,

[BMart.2]

Here is the code:

 /* Infinite loop */

 /* USER CODE BEGIN WHILE */

 char usbOut[256];

 while (1)

 {

  /* USER CODE END WHILE */

  /* USER CODE BEGIN 3 */

  sprintf(usbOut, "Hello World\r\n");

  //CDC_Transmit_FS(( uint8_t * )usbOut, strlen( usbOut ));

  USBD_CDC_SetTxBuffer(&hUsbDeviceFS, ( uint8_t * )usbOut, strlen( usbOut ));

  USBD_CDC_TransmitPacket(&hUsbDeviceFS);

  HAL_Delay(1000);   

  UTIL_SEQ_Run(~0);

 }

 /* USER CODE END 3 */

[XPonc.1]

Yes, I had the same issue. Apparently the BLE stack uses the USB clock for RNG purposes, and the clock can't have shared ressources.

See solution here:

https://community.st.com/s/question/0D50X0000C7cRcvSQE/problems-using-usb-mass-storage-middleware-with-ble-stack-on-stm32wb55

[BMart.2]

Thanks for the reply. I’ve actually implemented the code in the thread you’ve provided and I am still getting the same issue. The code is being called as I’ve got the define set to 1, but it seems to be the same behavior. I’ll keep digging.

[XPonc.1]

Oh, yes, it doesn't look the same as the problem I was facing: I did not have a hardfault, but my USB was not working

Also, as far as I know, you're supposed to have only the  UTIL_SEQ_Run(~0); in your while loop... If you want to print something (blink test with USB) try to set up a TIM interrupt that starts a new task in the sequencer.

Also, did you implement these 3 interrupts in your _it.c file? They are called by the RF stack.

/**
  * @brief This function handles RTC wake-up interrupt through EXTI line 19.
  */
void RTC_WKUP_IRQHandler(void)
{
  HW_TS_RTC_Wakeup_Handler();
}
/**
  * @brief This function handles IPCC RX occupied interrupt.
  */
void IPCC_C1_RX_IRQHandler(void)
{
  HW_IPCC_Rx_Handler();
}
/**
  * @brief This function handles IPCC TX free interrupt.
  */
void IPCC_C1_TX_IRQHandler(void)
{
  HW_IPCC_Tx_Handler();
}
 
/* USER CODE END 1 */

[BMart.2]

Thanks for your reply. I do have the 3 interrupts you’ve shown added. I had the usb code in the main loop for just testing it without the sequencer. I was not aware that UTIL_SEQ_Run(~0) could be the only function in the main loop. I’ll try adding that to the sequencer.
Thanks again